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Masango B, Goedecke JH, Ramsay M, Storbeck KH, Micklesfield LK, Chikowore T. Postprandial glucose variability and clusters of sex hormones, liver enzymes, and cardiometabolic factors in a South African cohort of African ancestry. BMJ Open Diabetes Res Care 2024; 12:e003927. [PMID: 38453238 PMCID: PMC10921533 DOI: 10.1136/bmjdrc-2023-003927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 02/16/2024] [Indexed: 03/09/2024] Open
Abstract
INTRODUCTION This study aimed to, first, determine the clusters of sex hormones, liver enzymes, and cardiometabolic factors associated with postprandial glucose (PPG) and, second to evaluate the variation these clusters account for jointly and independently with polygenic risk scores (PRSs) in South Africans of African ancestry men and women. RESEARCH DESIGN AND METHODS PPG was calculated as the integrated area under the curve for glucose during the oral glucose tolerance test (OGTT) using the trapezoidal rule in 794 participants from the Middle-aged Soweto Cohort. Principal component analysis was used to cluster sex hormones, liver enzymes, and cardiometabolic factors, stratified by sex. Multivariable linear regression was used to assess the proportion of variance in PPG accounted for by principal components (PCs) and type 2 diabetes (T2D) PRS while adjusting for selected covariates in men and women. RESULTS The T2D PRS did not contribute to the PPG variability in both men and women. In men, the PCs' cluster of sex hormones, liver enzymes, and cardiometabolic explained 10.6% of the variance in PPG, with PC1 (peripheral fat), PC2 (liver enzymes and steroid hormones), and PC3 (lipids and peripheral fat) contributing significantly to PPG. In women, PC factors of sex hormones, cardiometabolic factors, and liver enzymes explained a similar amount of the variance in PPG (10.8%), with PC1 (central fat) and PC2 (lipids and liver enzymes) contributing significantly to PPG. CONCLUSIONS We demonstrated that inter-individual differences in PPG responses to an OGTT may be differentially explained by body fat distribution, serum lipids, liver enzymes, and steroid hormones in men and women.
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Affiliation(s)
- Bontle Masango
- Division of Human Genetics, National Health Laboratory Service (NHLS), School of Pathology, University of the Witwatersrand, Faculty of Health Sciences, Johannesburg, South Africa
- South African Medical Research Council/University of the Witwatersrand, Developmental Pathways for Health Research Unit (DPHRU), University of the Witwatersrand, Faculty of Health Sciences, Johannesburg, South Africa
- Biomedical Research and Innovation Platform, South African Medical Research Council, Cape Town, South Africa
| | - Julia H Goedecke
- South African Medical Research Council/University of the Witwatersrand, Developmental Pathways for Health Research Unit (DPHRU), University of the Witwatersrand, Faculty of Health Sciences, Johannesburg, South Africa
- Biomedical Research and Innovation Platform, South African Medical Research Council, Cape Town, South Africa
| | - Michèle Ramsay
- Sydney Brenner Institute for Molecular Bioscience, University of the Witwatersrand, Faculty of Health Sciences, Johannesburg, South Africa
| | - Karl-Heinz Storbeck
- Department of Biochemistry, Stellenbosch University, Stellenbosch, South Africa
| | - Lisa K Micklesfield
- South African Medical Research Council/University of the Witwatersrand, Developmental Pathways for Health Research Unit (DPHRU), University of the Witwatersrand, Faculty of Health Sciences, Johannesburg, South Africa
| | - Tinashe Chikowore
- South African Medical Research Council/University of the Witwatersrand, Developmental Pathways for Health Research Unit (DPHRU), University of the Witwatersrand, Faculty of Health Sciences, Johannesburg, South Africa
- Harvard Medical School, Boston, Massachusetts, USA
- Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA
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Issaka A, Paradies Y, Cameron AJ, Stevenson C. The association between body weight indices, behavioral factors, and type 2 diabetes mellitus in Africa: A systematic review and meta-analysis of population-based epidemiological studies. Nutr Metab Cardiovasc Dis 2024; 34:1-18. [PMID: 38016892 DOI: 10.1016/j.numecd.2023.06.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 05/07/2023] [Accepted: 06/14/2023] [Indexed: 11/30/2023]
Abstract
BACKGROUND AND AIM Type 2 diabetes mellitus (T2DM) is a significant public health concern in Africa. While the associations between modifiable risk factors and T2DM are likely to be Africa-specific, their overall estimations have not been published. This study aimed to use systematic and meta-analytic methods to examine the strength of associations between modifiable risk factors and T2DM in Africa. METHODS AND RESULTS A systematic search of literature published between January 2000 to March 2022 was conducted. The review included only population-based studies and data extracted from 57 studies. Of these, unadjusted data from 50 studies were included in meta-analysis. With considerable heterogeneity between studies, random-effect models were calculated to ascertain the odds ratios (OR) and 95% confidence intervals (CI) for the associations between obesity (OB) and overweight (OV), defined by BMI; central obesity (waist circumference (OB-WC), waist-to-hip-ratio (OB-WHR)), alcohol, fruit and vegetable consumption, smoking, physical activity (PA) and T2DM. Moderator effects of age, African regions, and urban/rural location were assessed. Risk factors associated with T2DM include BMI-OB [OR = 3.05, 95% CI: (2.58, 3.61)], BMI-OV [OR = 2.38, 95% CI: (1.51, 3.75)], and BMI-OV/OB [OR = 2.07, 95% CI: (1.82, 2.34)]; OB-WC [OR = 2.58, 95% CI: (2.09, 3.18)] and OB-WHR [OR = 2.22, 95% CI: (1.69, 2.92)]; PA [OR = 1.85, 95% CI: (1.50, 2.30)]. Significant moderator effects were not observed. CONCLUSION Obesity defined by BMI and central obesity, but not behavioral risk factors were most strongly associated with T2DM in African populations, emphasizing the need for obesity prevention to limit the rise of T2DM. REGISTRATION The PROSPERO registration number is CRD42016043027.
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Affiliation(s)
- Ayuba Issaka
- Global Obesity Centre (GLOBE), School of Health and Social Development, Faculty of Health, Institute for Health Transformation, Deakin University, 1 Gheringhap St, Geelong, VIC 3220, Australia; Alfred Deakin Institute for Citizenship and Globalisation, Faculty of Arts and Education, Deakin University, 221 Burwood Highway, Burwood, VIC 3125, Australia; Baker Heart and Diabetes Institute, Non-Communicable Diseases and Implementation Science Unit, VIC, Australia.
| | - Yin Paradies
- Alfred Deakin Institute for Citizenship and Globalisation, Faculty of Arts and Education, Deakin University, 221 Burwood Highway, Burwood, VIC 3125, Australia
| | - Adrian J Cameron
- Global Obesity Centre (GLOBE), School of Health and Social Development, Faculty of Health, Institute for Health Transformation, Deakin University, 1 Gheringhap St, Geelong, VIC 3220, Australia
| | - Christopher Stevenson
- Global Obesity Centre (GLOBE), School of Health and Social Development, Faculty of Health, Institute for Health Transformation, Deakin University, 1 Gheringhap St, Geelong, VIC 3220, Australia
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Reed RM, Whyte MB, Goff LM. Cardiometabolic disease in Black African and Caribbean populations: an ethnic divergence in pathophysiology? Proc Nutr Soc 2023:1-11. [PMID: 38230432 DOI: 10.1017/s0029665123004895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
In the UK, populations of Black African and Caribbean (BAC) ethnicity suffer higher rates of cardiometabolic disease than White Europeans (WE). Obesity, leading to increased visceral adipose tissue (VAT) and intrahepatic lipid (IHL), has long been associated with cardiometabolic risk, driving insulin resistance and defective fatty acid/lipoprotein metabolism. These defects are compounded by a state of chronic low-grade inflammation, driven by dysfunctional adipose tissue. Emerging evidence has highlighted associations between central complement system components and adipose tissue, fatty acid metabolism and inflammation; it may therefore sit at the intersection of various cardiometabolic disease risk factors. However, increasing evidence suggests an ethnic divergence in pathophysiology, whereby current theories fail to explain the high rates of cardiometabolic disease in BAC populations. Lower fasting and postprandial TAG has been reported in BAC, alongside lower VAT and IHL deposition, which are paradoxical to the high rates of cardiometabolic disease exhibited by this ethnic group. Furthermore, BAC have been shown to exhibit a more anti-inflammatory profile, with lower TNF-α and greater IL-10. In contrast, recent evidence has revealed greater complement activation in BAC compared to WE, suggesting its dysregulation may play a greater role in the high rates of cardiometabolic disease experienced by this population. This review outlines the current theories of how obesity is proposed to drive cardiometabolic disease, before discussing evidence for ethnic differences in disease pathophysiology between BAC and WE populations.
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Affiliation(s)
- Reuben M Reed
- Department of Nutritional Sciences, Faculty of Life Sciences & Medicine, King's College London, London SE1 9NH, UK
| | - Martin B Whyte
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey GU2 7WG, UK
| | - Louise M Goff
- Leicester Diabetes Research Centre, University of Leicester, Leicester, UK
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Coetzee A, Hall DR, van de Vyver M, Conradie M. Early postpartum HbA1c after hyperglycemia first detected in pregnancy-Imperfect but not without value. PLoS One 2023; 18:e0282446. [PMID: 37289757 PMCID: PMC10249808 DOI: 10.1371/journal.pone.0282446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 05/11/2023] [Indexed: 06/10/2023] Open
Abstract
BACKGROUND South African women of childbearing age are disproportionally affected by obesity and at significant risk of Type 2 Diabetes Mellitus (T2DM). Unless pregnant, they do not readily undergo screening for T2DM. With a local focus on improved antenatal care, hyperglycemia is often first detected in pregnancy (HFDP). This may erroneously be attributed to Gestational Diabetes Mellitus (GDM) in all without considering T2DM. Glucose evaluation following pregnancy is essential for early detection and management of women with T2DM in whom persistent hyperglycemia is to be expected. Conventional testing with an oral glucose tolerance test (OGTT) is cumbersome, prompting investigation for alternate solutions. AIM To compare the diagnostic performance of HbA1c to the current gold standard OGTT in women with HFDP 4-12 weeks post-delivery. METHODS Glucose homeostasis was assessed with OGTT and HbA1c in 167 women with HFDP, 4-12 weeks after delivery. Glucose status was based on American Diabetes Association criteria. RESULTS Glucose homeostasis was assessed at 10 weeks (IQR 7-12) after delivery. Of the 167 participants, 52 (31%) had hyperglycemia, which was comprised of 34 (20%) prediabetes and 18 (11%) T2DM. Twelve women in the prediabetes subgroup had diagnostic fasting plasma glucose (FPG) and 2-hour plasma glucose (2hPG), but in two-thirds of the patients (22/34) only one time point proved diagnostic. The FPGs and the 2hPGs of six women with HbA1c-based T2DM were both within the prediabetes diagnostic range. According to the HbA1c measurements, 85% of 52 participants with gold standard OGTT defined hyperglycemia (prediabetes and T2DM) as well as 15 of 18 women with postpartum persistent T2DM were correctly classified. According to FPG, 15 women with persistent hyperglycemia would have been missed (11 with prediabetes and four with T2DM; 29%). When compared to an OGTT, a single HbA1c of 6.5% (48mmol/mol) postpartum demonstrated a sensitivity of 83% and specificity of 97% for the identification of T2DM. CONCLUSION HbA1c may improve access to postpartum testing in overburdened clinical settings where the required standards of OGTT cannot be guaranteed. HbA1c is a valuable test to detect women who will benefit most from early intervention but cannot unequivocally replace OGTT.
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Affiliation(s)
- Ankia Coetzee
- Department of Medicine, Division of Endocrinology Stellenbosch University and Tygerberg Hospital, Cape Town, South Africa
| | - David R. Hall
- Department of Obstetrics & Gynecology, Stellenbosch University and Tygerberg Hospital, Cape Town, South Africa
| | - Mari van de Vyver
- Department of Medicine, Division of Clinical Pharmacology, Stellenbosch University and Tygerberg Hospital, Cape Town, South Africa
| | - Magda Conradie
- Department of Obstetrics & Gynecology, Stellenbosch University and Tygerberg Hospital, Cape Town, South Africa
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Couch CA, Fowler LA, Goss AM, Gower BA. Associations of renal sinus fat with blood pressure and ectopic fat in a diverse cohort of adults. INTERNATIONAL JOURNAL OF CARDIOLOGY. CARDIOVASCULAR RISK AND PREVENTION 2023; 16:200165. [PMID: 36874041 PMCID: PMC9975207 DOI: 10.1016/j.ijcrp.2022.200165] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 12/04/2022] [Accepted: 12/10/2022] [Indexed: 12/23/2022]
Abstract
Background Renal sinus fat (RSF) is an ectopic fat depot shown to be associated with visceral adiposity and hypertension in predominantly white populations. The purpose of this analysis is to investigate RSF and associations between RSF and blood pressure in a cohort of African American (AA) and European American (EA) adults. A secondary purpose was to explore risk factors associated with RSF. Methods Participants were 116 A A and EA adult men and women. Ectopic fat depots were assessed with MRI: RSF, intraabdominal adipose tissue (IAAT), intermuscular adipose tissue (IMAT), perimuscular adipose tissue (PMAT), and liver fat. Cardiovascular measures included diastolic blood pressure (DBP), systolic blood pressure (SBP), pulse pressure, mean arterial pressure, and flow mediated dilation. Matsuda index was calculated for insulin sensitivity. Pearson correlations were used to investigate associations of RSF with cardiovascular measures. Multiple linear regression was used to evaluate contributions of RSF on SBP and DBP and to explore factors associated with RSF. Results No difference was observed in RSF between AA and EA participants. RSF was positively associated with DBP in AA participants, but this was not independent of age and sex. Age, male sex, and total body fat were positively associated with RSF in AA participants. Insulin sensitivity was inversely and IAAT and PMAT were positively associated with RSF in EA participants. Conclusions Differential associations of RSF with age, insulin sensitivity, and adipose depots among AA and EA adults suggest unique pathophysiological mechanisms influence RSF deposition, which may contribute to chronic disease etiology and progression.
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Affiliation(s)
- Catharine A. Couch
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Lauren A. Fowler
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Amy M. Goss
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Barbara A. Gower
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
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Mendham AE, Micklesfield LK, Karpe F, Kengne AP, Chikowore T, Kufe CN, Masemola M, Crowther NJ, Norris SA, Olsson T, Elmståhl S, Fall T, Lind L, Goedecke JH. Targeted proteomics identifies potential biomarkers of dysglycaemia, beta cell function and insulin sensitivity in Black African men and women. Diabetologia 2023; 66:174-189. [PMID: 36114877 DOI: 10.1007/s00125-022-05788-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 06/09/2022] [Indexed: 12/13/2022]
Abstract
AIMS/HYPOTHESIS Using a targeted proteomics approach, we aimed to identify and validate circulating proteins associated with impaired glucose metabolism (IGM) and type 2 diabetes in a Black South African cohort. In addition, we assessed sex-specific associations between the validated proteins and pathophysiological pathways of type 2 diabetes. METHODS This cross-sectional study included Black South African men (n=380) and women (n=375) who were part of the Middle-Aged Soweto Cohort (MASC). Dual-energy x-ray absorptiometry was used to determine fat mass and visceral adipose tissue, and fasting venous blood samples were collected for analysis of glucose, insulin and C-peptide and for targeted proteomics, measuring a total of 184 pre-selected protein biomarkers. An OGTT was performed on participants without diabetes, and peripheral insulin sensitivity (Matsuda index), HOMA-IR, basal insulin clearance, insulin secretion (C-peptide index) and beta cell function (disposition index) were estimated. Participants were classified as having normal glucose tolerance (NGT; n=546), IGM (n=116) or type 2 diabetes (n=93). Proteins associated with dysglycaemia (IGM or type 2 diabetes) in the MASC were validated in the Swedish EpiHealth cohort (NGT, n=1706; impaired fasting glucose, n=550; type 2 diabetes, n=210). RESULTS We identified 73 proteins associated with dysglycaemia in the MASC, of which 34 were validated in the EpiHealth cohort. Among these validated proteins, 11 were associated with various measures of insulin dynamics, with the largest number of proteins being associated with HOMA-IR. In sex-specific analyses, IGF-binding protein 2 (IGFBP2) was associated with lower HOMA-IR in women (coefficient -0.35; 95% CI -0.44, -0.25) and men (coefficient -0.09; 95% CI -0.15, -0.03). Metalloproteinase inhibitor 4 (TIMP4) was associated with higher insulin secretion (coefficient 0.05; 95% CI 0.001, 0.11; p for interaction=0.025) and beta cell function (coefficient 0.06; 95% CI 0.02, 0.09; p for interaction=0.013) in women only. In contrast, a stronger positive association between IGFBP2 and insulin sensitivity determined using an OGTT (coefficient 0.38; 95% CI 0.27, 0.49) was observed in men (p for interaction=0.004). A posteriori analysis showed that the associations between TIMP4 and insulin dynamics were not mediated by adiposity. In contrast, most of the associations between IGFBP2 and insulin dynamics, except for insulin secretion, were mediated by either fat mass index or visceral adipose tissue in men and women. Fat mass index was the strongest mediator between IGFBP2 and insulin sensitivity (total effect mediated 40.7%; 95% CI 37.0, 43.6) and IGFBP2 and HOMA-IR (total effect mediated 39.1%; 95% CI 31.1, 43.5) in men. CONCLUSIONS/INTERPRETATION We validated 34 proteins that were associated with type 2 diabetes, of which 11 were associated with measures of type 2 diabetes pathophysiology such as peripheral insulin sensitivity and beta cell function. This study highlights biomarkers that are similar between cohorts of different ancestry, with different lifestyles and sociodemographic profiles. The African-specific biomarkers identified require validation in African cohorts to identify risk markers and increase our understanding of the pathophysiology of type 2 diabetes in African populations.
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Affiliation(s)
- Amy E Mendham
- South African Medical Research Council/WITS Developmental Pathways for Health Research Unit, Department of Paediatrics, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
- Health through Physical Activity, Lifestyle and Sport Research Centre, International Federation of Sports Medicine (FIMS), International Collaborating Centre of Sports Medicine, Division of Physiological Sciences, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
| | - Lisa K Micklesfield
- South African Medical Research Council/WITS Developmental Pathways for Health Research Unit, Department of Paediatrics, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Fredrik Karpe
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, UK
- National Institute for Health and Care Research, Oxford Biomedical Research Centre, Oxford University Hospitals Foundation Trust, Oxford, UK
| | - Andre Pascal Kengne
- Biomedical Research and Innovation Platform and Non-Communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa
| | - Tinashe Chikowore
- South African Medical Research Council/WITS Developmental Pathways for Health Research Unit, Department of Paediatrics, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Clement N Kufe
- South African Medical Research Council/WITS Developmental Pathways for Health Research Unit, Department of Paediatrics, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Epidemiology and Surveillance Section, National Institute for Occupational Health, National Health Laboratory Service, Johannesburg, South Africa
| | - Maphoko Masemola
- South African Medical Research Council/WITS Developmental Pathways for Health Research Unit, Department of Paediatrics, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Nigel J Crowther
- Department of Chemical Pathology, National Health Laboratory Service and University of the Witwatersrand Faculty of Health Sciences, Johannesburg, South Africa
| | - Shane A Norris
- South African Medical Research Council/WITS Developmental Pathways for Health Research Unit, Department of Paediatrics, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- School of Human Development and Health, University of Southampton, Southampton, UK
| | - Tommy Olsson
- Department of Public Health and Clinical Medicine, Medicine, Umeå University, Umeå, Sweden
| | - Sölve Elmståhl
- Department of Clinical Sciences in Malmö, Division of Geriatric Medicine, Lund University, Lund, Sweden
- Clinical Research Centre, Skåne University Hospital, Malmö, Sweden
| | - Tove Fall
- Department of Medical Sciences, Molecular Epidemiology and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Lars Lind
- Department of Medical Sciences, Uppsala University Hospital, Uppsala University, Uppsala, Sweden
| | - Julia H Goedecke
- South African Medical Research Council/WITS Developmental Pathways for Health Research Unit, Department of Paediatrics, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Health through Physical Activity, Lifestyle and Sport Research Centre, International Federation of Sports Medicine (FIMS), International Collaborating Centre of Sports Medicine, Division of Physiological Sciences, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Biomedical Research and Innovation Platform and Non-Communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa
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Goedecke JH, Mendham AE. Pathophysiology of type 2 diabetes in sub-Saharan Africans. Diabetologia 2022; 65:1967-1980. [PMID: 36166072 PMCID: PMC9630207 DOI: 10.1007/s00125-022-05795-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 07/12/2022] [Indexed: 01/11/2023]
Abstract
Sub-Saharan Africa (SSA) is the region with the highest projected rates of increase in type 2 diabetes (129% by 2045), which will exacerbate the already high prevalence of type 2 diabetes complications and comorbidities in SSA. In addition, SSA is grappling with poverty-related health problems and infectious diseases and is also undergoing the most rapid rates of urbanisation globally. These socioenvironmental and lifestyle factors may interact with genetic factors to alter the pathophysiological sequence leading to type 2 diabetes in sub-Saharan African populations. Indeed, current evidence from SSA and the diaspora suggests that the pathophysiology of type 2 diabetes in Black Africans is different from that in their European counterparts. Studies from the diaspora suggest that insulin clearance is the primary defect underlying the development of type 2 diabetes. We propose that, among Black Africans from SSA, hyperinsulinaemia due to a combination of both increased insulin secretion and reduced hepatic insulin clearance is the primary defect, which promotes obesity and insulin resistance, exacerbating the hyperinsulinaemia and eventually leading to beta cell failure and type 2 diabetes. Nonetheless, the current understanding of the pathogenesis of type 2 diabetes and the clinical guidelines for preventing and managing the disease are largely based on studies including participants of predominately White European ancestry. In this review, we summarise the existing knowledge base and data from the only non-pharmacological intervention that explores the pathophysiology of type 2 diabetes in SSA. We also highlight factors that may influence the pathogenesis of type 2 diabetes in SSA, such as social determinants, infectious diseases and genetic and epigenetic influences.
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Affiliation(s)
- Julia H Goedecke
- Biomedical Research and Innovation Platform and Non-Communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa.
- South African Medical Research Council/WITS Developmental Pathways for Health Research Unit (DPHRU), Department of Paediatrics, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
- Health through Physical Activity, Lifestyle and Sport Research Centre (HPALS), FIMS International Collaborating Centre of Sports Medicine, Division of Physiological Sciences, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
| | - Amy E Mendham
- South African Medical Research Council/WITS Developmental Pathways for Health Research Unit (DPHRU), Department of Paediatrics, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Health through Physical Activity, Lifestyle and Sport Research Centre (HPALS), FIMS International Collaborating Centre of Sports Medicine, Division of Physiological Sciences, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
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Motala AA, Mbanya JC, Ramaiya K, Pirie FJ, Ekoru K. Type 2 diabetes mellitus in sub-Saharan Africa: challenges and opportunities. Nat Rev Endocrinol 2022; 18:219-229. [PMID: 34983969 DOI: 10.1038/s41574-021-00613-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/25/2021] [Indexed: 12/26/2022]
Abstract
Type 2 diabetes mellitus (T2DM), which was once thought to be rare in sub-Saharan Africa (SSA), is now well established in this region. The SSA region is undergoing a rapid but variable epidemiological transition fuelled by the pace of urbanization, with disease burden profiles shifting from communicable diseases to non-communicable diseases (NCDs). Information on the epidemiology of T2DM has increased, but wide variations in study methods, diagnostic biomarkers and criteria hamper analytical comparison, and data from high-quality studies are limited. The prevalence of T2DM is still low in some rural populations but moderate or high rates are reported in many countries/regions, with evidence for an increase in some. In addition, the proportion of undiagnosed T2DM is still high. The prevalence of T2DM is highest in African people living in urban areas, and the gradient between African people living in urban areas and people in the African diaspora is rapidly fading. However, data from longitudinal studies are lacking and there is limited information on chronic complications and the genetics of T2DM. The large unmet needs for T2DM care call for greater investment of resources into health systems to manage NCDs in SSA. Proposed health-system paradigms are being developed in some countries/regions. However, national NCD programmes need to be adequately funded and coordinated to stem the tide of T2DM and its complications.
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Affiliation(s)
- Ayesha A Motala
- Inkosi Albert Luthuli Central Hospital, Durban, South Africa.
- Department of Diabetes and Endocrinology, University of KwaZulu-Natal, Durban, South Africa.
| | - Jean Claude Mbanya
- Department of Internal Medicine and Specialities, Faculty of Medicine and Biomedical Sciences University of Yaounde 1, Yaounde, Cameroon
| | | | - Fraser J Pirie
- Inkosi Albert Luthuli Central Hospital, Durban, South Africa
- Department of Diabetes and Endocrinology, University of KwaZulu-Natal, Durban, South Africa
| | - Kenneth Ekoru
- Centre for Research on Genomics and Global Health, National Human Genome Research Institute, National Institute of Health, Bethesda, MD, USA
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Kufe CN, Micklesfield LK, Masemola M, Chikowore T, Kengne AP, Karpe F, Norris SA, Crowther NJ, Olsson T, Goedecke JH. Increased risk for type 2 diabetes in relation to adiposity in middle-aged Black South African men compared to women. Eur J Endocrinol 2022; 186:523-533. [PMID: 35225824 PMCID: PMC9010812 DOI: 10.1530/eje-21-0527] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 02/28/2022] [Indexed: 11/08/2022]
Abstract
AIMS Despite a higher prevalence of overweight/obesity in Black South African women compared to men, the prevalence of type 2 diabetes (T2D) does not differ. We explored if this could be due to sex differences in insulin sensitivity, clearance and/or beta-cell function and also sex-specific associations with total and regional adiposity. METHODS This cross-sectional study included 804 Black South African men (n = 388) and women (n = 416). Dual-energy X-ray absorptiometry was used to measure total and regional adiposity. Insulin sensitivity (Matsuda index), secretion (C-peptide index) and clearance (C-peptide/insulin ratio) were estimated from an oral glucose tolerance test. RESULTS After adjusting for sex differences in the fat mass index, men were less insulin sensitive and had lower beta-cell function than women (P < 0.001), with the strength of the associations with measures of total and central adiposity being greater in men than women (P < 0.001 for interactions). Further, the association between total adiposity and T2D risk was also greater in men than women (relative risk ratio (95% CI): 2.05 (1.42-2.96), P < 0.001 vs 1.38 (1.03-1.85), P = 0.031). CONCLUSION With increasing adiposity, particularly increased centralisation of body fat linked to decreased insulin sensitivity and beta-cell function, Black African men are at greater risk for T2D than their female counterparts.
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Affiliation(s)
- Clement N Kufe
- Department of Paediatrics, South African Medical Research Council (SAMRC), WITS, Developmental Pathways for Health Research Unit (DPHRU), Faculty of Health Sciences, Department of Paediatrics, University of the Witwatersrand, Johannesburg, South Africa
- Correspondence should be addressed to C Kufe;
| | - Lisa K Micklesfield
- Department of Paediatrics, South African Medical Research Council (SAMRC), WITS, Developmental Pathways for Health Research Unit (DPHRU), Faculty of Health Sciences, Department of Paediatrics, University of the Witwatersrand, Johannesburg, South Africa
| | - Maphoko Masemola
- Department of Paediatrics, South African Medical Research Council (SAMRC), WITS, Developmental Pathways for Health Research Unit (DPHRU), Faculty of Health Sciences, Department of Paediatrics, University of the Witwatersrand, Johannesburg, South Africa
| | - Tinashe Chikowore
- Department of Paediatrics, South African Medical Research Council (SAMRC), WITS, Developmental Pathways for Health Research Unit (DPHRU), Faculty of Health Sciences, Department of Paediatrics, University of the Witwatersrand, Johannesburg, South Africa
| | - Andre P Kengne
- Non-Communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa
| | - Fredrik Karpe
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, UK
- National Institute for Health Research, Oxford Biomedical Research Centre, Oxford Radcliffe Hospitals Trust, OCDEM, Churchill Hospital, Oxford, UK
| | - Shane A Norris
- Department of Paediatrics, South African Medical Research Council (SAMRC), WITS, Developmental Pathways for Health Research Unit (DPHRU), Faculty of Health Sciences, Department of Paediatrics, University of the Witwatersrand, Johannesburg, South Africa
- Global Health Research Institute, School of Human Development and Health, University of Southampton, Southampton, UK
| | - Nigel J Crowther
- Department of Chemical Pathology, National Health Laboratory Service and School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Tommy Olsson
- Department of Public Health and Clinical Medicine, Medicine, Umeå University, Umeå, Sweden
| | - Julia H Goedecke
- Department of Paediatrics, South African Medical Research Council (SAMRC), WITS, Developmental Pathways for Health Research Unit (DPHRU), Faculty of Health Sciences, Department of Paediatrics, University of the Witwatersrand, Johannesburg, South Africa
- Non-Communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa
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10
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Koh HCE, Patterson BW, Reeds DN, Mittendorfer B. Insulin sensitivity and kinetics in African American and White people with obesity: Insights from different study protocols. Obesity (Silver Spring) 2022; 30:655-665. [PMID: 35083870 PMCID: PMC8866210 DOI: 10.1002/oby.23363] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/28/2021] [Accepted: 12/02/2021] [Indexed: 01/03/2023]
Abstract
OBJECTIVE Studies that used an intravenous glucose tolerance test (IVGTT) have suggested that race is an important modulator of insulin sensitivity, β-cell function, and insulin clearance. However, the validity of the IVGTT has been challenged. METHODS This study assessed insulin sensitivity and insulin kinetics in non-Hispanic White (NHW, n = 29) and African American (AA, n = 14) people with obesity by using a hyperinsulinemic-euglycemic pancreatic clamp with glucose tracer infusion, an oral glucose tolerance test (OGTT), and an IVGTT. RESULTS Hepatic insulin sensitivity was better in AA participants than in NHW participants. Muscle insulin sensitivity, insulin secretion in relation to plasma glucose during the OGTT, and insulin clearance during basal conditions during the hyperinsulinemic-euglycemic pancreatic clamp and during the OGTT were not different between AA participants and NHW participants. The acute insulin response to the large glucose bolus administered during the IVGTT was double in AA participants compared with NHW participants because of increased insulin secretion and reduced insulin clearance. CONCLUSIONS AA individuals are not more insulin resistant than NHW individuals, and the β-cell response to glucose ingestion and postprandial insulin clearance are not different between AA individuals and NHW individuals. However, AA individuals have greater insulin secretory capacity and reduced insulin clearance capacity than NHW individuals and might be susceptible to hyperinsulinemia after consuming very large amounts of glucose.
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Affiliation(s)
- Han-Chow E Koh
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Bruce W Patterson
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Dominic N Reeds
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Bettina Mittendorfer
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri, USA
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11
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Reed RM, Nevitt SJ, Kemp GJ, Cuthbertson DJ, Whyte MB, Goff LM. Ectopic fat deposition in populations of black African ancestry: A systematic review and meta-analysis. Acta Diabetol 2022; 59:171-187. [PMID: 34518896 PMCID: PMC8841318 DOI: 10.1007/s00592-021-01797-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 09/02/2021] [Indexed: 02/07/2023]
Abstract
AIMS In populations of black African ancestry (BA), a paradox exists whereby lower visceral adipose tissue is found despite their high risk for type 2 diabetes (T2D). This systematic review investigates ethnic differences in other ectopic fat depots (intrahepatic lipid: IHL; intramyocellular lipid: IMCL and intrapancreatic lipid; IPL) to help contextualise their potential contribution to T2D risk. METHODS A systematic literature search was performed in December 2020 to identify studies reporting at least one ectopic fat comparison between BA and one/more other ethnicity. For IHL, a meta-analysis was carried out with studies considered comparable based on the method of measurement. RESULTS Twenty-eight studies were included (IHL: n = 20; IMCL: n = 8; IPL: n = 4). Meta-analysis of 11 studies investigating IHL revealed that it was lower in BA populations vs pooled ethnic comparators (MD -1.35%, 95% CI -1.55 to -1.16, I2 = 85%, P < 0.00001), white European ancestry (MD -0.94%, 95% CI -1.17 to -0.70, I2 = 79%, P < 0.00001), Hispanic ancestry (MD -2.06%, 95% CI -2.49 to -1.63, I2 = 81%, P < 0.00001) and South Asian ancestry comparators (MD -1.92%, 95% CI -3.26 to -0.57, I2 = 78%, P = 0.005). However, heterogeneity was high in all analyses. Most studies found no significant differences in IMCL between BA and WE. Few studies investigated IPL, however, indicated that IPL is lower in BA compared to WE and HIS. CONCLUSION The discordance between ectopic fat and greater risk for T2D in BA populations raises questions around its contribution to T2D pathophysiology in BA.
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Affiliation(s)
- Reuben M Reed
- Department of Nutritional Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Sarah J Nevitt
- Department of Health Data Science, Institute of Population Health, University of Liverpool, Liverpool, UK
| | - Graham J Kemp
- Department of Musculoskeletal and Ageing Science. Institute of Life Course and Medical Sciences, Liverpool Magnetic Resonance Imaging Centre (LiMRIC), University of Liverpool, Liverpool, UK
| | - Daniel J Cuthbertson
- Department of Cardiovascular and Metabolic Medicine, Institute of Life Course Sciences, University of Liverpool, Liverpool, UK
| | - Martin B Whyte
- Faculty of Health & Medical Sciences, University of Surrey, Guildford, Surrey, UK
| | - Louise M Goff
- Department of Nutritional Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK.
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12
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Price CA, Jospin G, Brownell K, Eisen JA, Laraia B, Epel ES. Differences in gut microbiome by insulin sensitivity status in Black and White women of the National Growth and Health Study (NGHS): A pilot study. PLoS One 2022; 17:e0259889. [PMID: 35045086 PMCID: PMC8769296 DOI: 10.1371/journal.pone.0259889] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 10/28/2021] [Indexed: 12/22/2022] Open
Abstract
The prevalence of overweight and obesity is greatest amongst Black women in the U.S., contributing to disproportionately higher type 2 diabetes prevalence compared to White women. Insulin resistance, independent of body mass index, tends to be greater in Black compared to White women, yet the mechanisms to explain these differences are not completely understood. The gut microbiome is implicated in the pathophysiology of obesity, insulin resistance and cardiometabolic disease. Only two studies have examined race differences in Black and White women, however none characterizing the gut microbiome based on insulin sensitivity by race and sex. Our objective was to determine if gut microbiome profiles differ between Black and White women and if so, determine if these race differences persisted when accounting for insulin sensitivity status. In a pilot cross-sectional analysis, we measured the relative abundance of bacteria in fecal samples collected from a subset of 168 Black (n = 94) and White (n = 74) women of the National Growth and Health Study (NGHS). We conducted analyses by self-identified race and by race plus insulin sensitivity status (e.g. insulin sensitive versus insulin resistant as determined by HOMA-IR). A greater proportion of Black women were classified as IR (50%) compared to White women (30%). Alpha diversity did not differ by race nor by race and insulin sensitivity status. Beta diversity at the family level was significantly different by race (p = 0.033) and by the combination of race plus insulin sensitivity (p = 0.038). Black women, regardless of insulin sensitivity, had a greater relative abundance of the phylum Actinobacteria (p = 0.003), compared to White women. There was an interaction between race and insulin sensitivity for Verrucomicrobia (p = 0.008), where among those with insulin resistance, Black women had four fold higher abundance than White women. At the family level, we observed significant interactions between race and insulin sensitivity for Lachnospiraceae (p = 0.007) and Clostridiales Family XIII (p = 0.01). Our findings suggest that the gut microbiome, particularly lower beta diversity and greater Actinobacteria, one of the most abundant species, may play an important role in driving cardiometabolic health disparities of Black women, indicating an influence of social and environmental factors on the gut microbiome.
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Affiliation(s)
- Candice A. Price
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA, United States of America
| | - Guillaume Jospin
- Genome Center, University of California Davis, Davis, CA, United States of America
| | - Kristy Brownell
- Center for Obesity Assessment, Study and Treatment, University of California, San Francisco, California, United States of America
- School of Public Health, University of California, Berkeley, California, United States of America
| | - Jonathan A. Eisen
- Genome Center, University of California Davis, Davis, CA, United States of America
- Department of Evolution and Ecology, University of California, Davis, CA, United States of America
- Department of Medical Microbiology and Immunology, University of California, Davis, CA, United States of America
| | - Barbara Laraia
- Center for Obesity Assessment, Study and Treatment, University of California, San Francisco, California, United States of America
- School of Public Health, University of California, Berkeley, California, United States of America
| | - Elissa S. Epel
- Department of Psychiatry, University of California, San Francisco, CA, United States of America
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13
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Fortuin-de Smidt MC, Mendham AE, Hauksson J, Alhamud A, Stefanovski D, Hakim O, Swart J, Goff LM, Kahn SE, Olsson T, Goedecke JH. β-cell function in black South African women: exploratory associations with insulin clearance, visceral and ectopic fat. Endocr Connect 2021; 10:550-560. [PMID: 33884957 PMCID: PMC8183622 DOI: 10.1530/ec-21-0153] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Accepted: 04/22/2021] [Indexed: 11/08/2022]
Abstract
The role of ectopic fat, insulin secretion and clearance in the preservation ofβ-cell function in black African women with obesity who typically present with hyperinsulinaemia is not clear. We aim to examine the associations between disposition index (DI, an estimate of β-cell function), insulin secretion and clearance and ectopic fat deposition. This is a cross-sectional study of 43 black South African women (age 20-35 years) with obesity (BMI 30-40 kg/m2) and without type 2 diabetes that measured the following: DI, insulin sensitivity (SI), acute insulin response (AIRg), insulin secretion rate (ISR), hepatic insulin extraction and peripheral insulin clearance (frequently sampled i.v. glucose tolerance test); pancreatic and hepatic fat, visceral adipose tissue (VAT) and abdominal s.c. adipose tissue (aSAT) volume (MRI), intra-myocellular (IMCL) and extra-myocellular fat content (EMCL) (magnetic resonance spectroscopy). DI correlated positively with peripheral insulin clearance (β 55.80, P = 0.002). Higher DI was associated with lower VAT, pancreatic fat and soleus fat, but VAT explained most of the variance in DI (32%). Additionally, higher first phase ISR (P = 0.033) and lower hepatic insulin extraction (P = 0.022) were associated with lower VAT, independent from SI, rather than with ectopic fat. In conclusion, peripheral insulin clearance emerged as an important correlate of DI. However, VAT was the main determinant of a lower DI above ectopic fat depots. Importantly, VAT, but not ectopic fat, is associated with both lower insulin secretion and higher hepatic insulin extraction. Prevention of VAT accumulation in young black African women should, therefore, be an important target for beta cell preservation.
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Affiliation(s)
- Melony C Fortuin-de Smidt
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
- Non-Communicable Diseases Research Unit, South African Medical Council, Tygerberg, South Africa
- Correspondence should be addressed to M C Fortuin-de Smidt:
| | - Amy E Mendham
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
- Non-Communicable Diseases Research Unit, South African Medical Council, Tygerberg, South Africa
| | - Jon Hauksson
- Department of Radiation Sciences, Radiation Physics and Biomedical Engineering, Umea University, Umea, Sweden
| | - Ali Alhamud
- Department of Human Biology, MRC/UCT Medical Imaging Research Unit, University of Cape Town, Cape Town, South Africa
- The Modern Pioneer Center and ArSMRM for MRI Training and Development, Tripoli, Libya
| | - Darko Stefanovski
- Department of Clinical Studies, New Bolton Centre, University of Pennsylvania School of Veterinary Medicine, Kennett Square, Pennsylvania, USA
| | - Olah Hakim
- Department of Diabetes, Faculty of Life Sciences and Medicine, School of Life Course Sciences, King’s College London, London, UK
| | - Jeroen Swart
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
| | - Louise M Goff
- Department of Diabetes, Faculty of Life Sciences and Medicine, School of Life Course Sciences, King’s College London, London, UK
| | - Steven E Kahn
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, Veterans Affairs Puget Sound Health Care System, University of Washington, Seattle, Washington, USA
| | - Tommy Olsson
- Department of Public Health and Clinical Medicine, Umea University, Umea, Sweden
| | - Julia H Goedecke
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
- Non-Communicable Diseases Research Unit, South African Medical Council, Tygerberg, South Africa
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14
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Lee M, Kim KJ, Chung TH, Bae J, Lee YH, Lee BW, Cha BS, Yun M, Kang ES. Nonalcoholic fatty liver disease, diastolic dysfunction, and impaired myocardial glucose uptake in patients with type 2 diabetes. Diabetes Obes Metab 2021; 23:1041-1051. [PMID: 33394549 DOI: 10.1111/dom.14310] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 12/15/2020] [Accepted: 12/23/2020] [Indexed: 12/13/2022]
Abstract
AIMS To investigate whether degree of nonalcoholic fatty liver disease (NAFLD) is associated with myocardial dysfunction related to impaired myocardial glucose uptake in patients with type 2 diabetes. MATERIALS AND METHODS In total, 131 patients with type 2 diabetes from a tertiary care hospital were included in this study. Myocardial glucose uptake was assessed using [18 F]-fluorodeoxyglucose-positron emission tomography. Hepatic steatosis and fibrosis were determined using transient liver elastography. Echocardiography was performed to evaluate cardiac structure and function. RESULTS Patients with NAFLD had cardiac diastolic dysfunction with higher left ventricular filling pressure (E/e' ratio) and left atrial (LA) volume index than patients without NAFLD (all P < 0.05). Hepatic steatosis correlated with E/e' ratio and LA volume index, and hepatic fibrosis also correlated with E/e' ratio (all P < 0.05). Even after adjusting for confounding factors, a higher degree of hepatic steatosis (r2 = 0.409, P = 0.041) and a higher degree of fibrosis (r2 = 0.423, P = 0.009) were independent contributing factors to a higher E/e' ratio. Decreased myocardial glucose uptake was associated with a higher degree of steatosis (P for trend = 0.084) and fibrosis (P for trend = 0.012). At the same time, decreased myocardial glucose uptake was an independent contributing factor for a higher E/e' ratio (r2 = 0.409; P = 0.040). CONCLUSIONS Hepatic steatosis and fibrosis were significantly associated with diastolic heart dysfunction in patients with type 2 diabetes coupled with impaired myocardial glucose uptake.
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Affiliation(s)
- Minyoung Lee
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Kwang Joon Kim
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Tae-Ha Chung
- Department of Health Promotion, Severance Check-up, Health Promotion Center, Severance Hospital, Yonsei University Health System, Seoul, Republic of Korea
| | - Jaehyun Bae
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Yong-Ho Lee
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Institute of Endocrine Research, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Byung-Wan Lee
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Institute of Endocrine Research, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Bong-Soo Cha
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Institute of Endocrine Research, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Mijin Yun
- Department of Nuclear Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Eun Seok Kang
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
- Institute of Endocrine Research, Yonsei University College of Medicine, Seoul, Republic of Korea
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15
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Goedecke JH, Chorell E, van Jaarsveld PJ, Risérus U, Olsson T. Fatty Acid Metabolism and Associations with Insulin Sensitivity Differs Between Black and White South African Women. J Clin Endocrinol Metab 2021; 106:e140-e151. [PMID: 32995848 DOI: 10.1210/clinem/dgaa696] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Accepted: 09/28/2020] [Indexed: 01/22/2023]
Abstract
PURPOSE Genetic differences in desaturase genes and consequently fatty acid metabolism have been reported. The aims were to examine ethnic differences in serum fatty acid composition and desaturase indices, and assess the ethnic-specific associations with insulin sensitivity (IS) and liver fat in black and white South African (SA) women. METHODS In this cross-sectional study including 92 premenopausal black (n = 46) and white (n = 46) SA women, serum fatty acid composition was measured in cholesteryl ester (CE) and nonesterified fatty acid (NEFA) fractions. Desaturase activities were estimated as product-to-precursor ratios: stearoyl-CoA desaturase-1 (SCD1-16, 16:1n-7/16:0); δ-5 desaturase (D5D, 20:4n-6/20:3n-6), and δ-6 desaturase (D6D, 18:3n-6/18:2n-6). Whole-body IS was estimated from an oral glucose tolerance test using the Matsuda index. In a subsample (n = 30), liver fat and hepatic IS were measured by 1H-magnetic resonance spectroscopy and hyperinsulinemic euglycemic clamp, respectively. RESULTS Despite lower whole-body IS (P = .006), black women had higher CE D5D and lower D6D and SCD1-16 indices than white women (P < .01). CE D6D index was associated with lower IS in white women only (r = -0.31, P = .045), whereas D5D index was associated with higher IS in black women only (r = 0.31, P = .041). In the subsample, D6D and SCD1-16 indices were positively and D5D was negatively associated with liver fat (P < .05). Conversely, CE SCD1-16 was negatively associated with hepatic IS (P < .05), but not independently of liver fat. CONCLUSIONS Ethnic differences in fatty acid-derived desaturation indices were observed, with insulin-resistant black SA women paradoxically showing a fatty acid pattern typical for higher insulin sensitivity in European populations.
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Affiliation(s)
- Julia H Goedecke
- Non-communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa
- Department of Human Biology, University of Cape Town, Cape Town, South Africa
| | - Elin Chorell
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
| | - Paul J van Jaarsveld
- Non-communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa
| | - Ulf Risérus
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Tommy Olsson
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
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16
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Goedecke JH, Olsson T. Pathogenesis of type 2 diabetes risk in black Africans: a South African perspective. J Intern Med 2020; 288:284-294. [PMID: 32303113 DOI: 10.1111/joim.13083] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 02/25/2020] [Accepted: 03/02/2020] [Indexed: 12/16/2022]
Abstract
The prevalence of type 2 diabetes (T2D) is higher in black Africans than their European counterparts. This review summarizes the research exploring the pathogenesis of T2D in populations of African ancestry compared to white Europeans and shows that the pathogenesis differs by ethnicity. Black Africans present with a phenotype of low insulin sensitivity and hyperinsulinaemia as a result of increased insulin secretion and reduced hepatic insulin clearance. Whether hyperinsulinaemia precedes insulin resistance or is merely a compensatory mechanism is yet to be determined. Black Africans have lower visceral adipose tissue and ectopic fat deposition and greater peripheral (gluteo-femoral) fat deposition than their European counterparts. This suggests that black Africans are more sensitive to the effects of ectopic fat deposition, or alternatively, that ectopic fat is not an important mediator of T2D in black Africans. Importantly, ethnic disparities in T2D risk factors may be confounded by differences in sociocultural and lifestyle factors. Future longitudinal and dietary intervention studies, in combination with genetic analyses, are needed for a better understanding of the pathophysiology of T2D in black Africans. This will be key for effective prevention and management strategies.
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Affiliation(s)
- J H Goedecke
- From the, Non-Communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa
| | - T Olsson
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
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17
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Affiliation(s)
- Julia H Goedecke
- From the Non-Communicable Diseases Research Unit, South African Medical Research Council, Cape Town
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18
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Hakim O, Bello O, Bonadonna RC, Mohandas C, Shojaee-Moradie F, Jackson N, Boselli L, Whitcher B, Shuaib H, Alberti KGMM, Peacock JL, Umpleby AM, Charles-Edwards G, Amiel SA, Goff LM. Ethnic differences in intrahepatic lipid and its association with hepatic insulin sensitivity and insulin clearance between men of black and white ethnicity with early type 2 diabetes. Diabetes Obes Metab 2019; 21:2163-2168. [PMID: 31074174 DOI: 10.1111/dom.13771] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 05/03/2019] [Accepted: 05/07/2019] [Indexed: 12/24/2022]
Abstract
Intrahepatic lipid (IHL) is linked with reduced hepatic insulin sensitivity and insulin clearance. Despite their high risk for type 2 diabetes (T2D), there have been limited investigations of these relationships in black populations. We investigated these relationships in 18 white European (WE) and 18 black West African (BWA) men with T2D <5 years. They underwent magnetic resonance imaging to quantify IHL, a hyperinsulinemic euglycaemic clamp with [6,6 2 H2 ] glucose infusion to assess hepatic insulin sensitivity and a hyperglycaemic clamp to assess insulin clearance. BWA men had lower IHL than WE men (3.7 [5.3] vs 6.6 [10.6]%, P = 0.03). IHL was inversely associated with basal hepatic insulin sensitivity in WE but not BWA men (BWA: r = -0.01, P = 0.96; WE: r = -0.72, P = 0.006) with a significant interaction by ethnicity (Pinteraction = 0.05); however, IHL was not associated with % suppression of endogenous glucose production by insulin in either ethnicity. IHL showed a trend to an association with insulin clearance in BWA only (BWA: r = -0.42, P = 0.09; WE: r = -0.14, P = 0.58). The lack of association between IHL and hepatic insulin sensitivity in BWA men indicates IHL may play a lesser detrimental role in T2D in BWA men.
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Affiliation(s)
- Olah Hakim
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Oluwatoyosi Bello
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Riccardo C Bonadonna
- Department of Medicine & Surgery, University of Parma and Azienda Ospedaliera, Universitaria di Parma, Parma, Italy
| | - Cynthia Mohandas
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | | | - Nicola Jackson
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Linda Boselli
- Division of Endocrinology and Metabolic Disease, University of Verona School of Medicine, Verona, Italy
| | - Brandon Whitcher
- Research Centre for Optimal Health, School of Life Sciences, University of Westminster, London, UK
| | - Haris Shuaib
- Department of Medical Physics, Guy's & St Thomas' NHS Foundation Trust, London, UK
- Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Kurt George M M Alberti
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Janet L Peacock
- School of Population Health and Environmental Sciences, King's College London, London, UK
| | | | - Geoffrey Charles-Edwards
- Department of Medical Physics, Guy's & St Thomas' NHS Foundation Trust, London, UK
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
| | - Stephanie A Amiel
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Louise M Goff
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
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19
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Abstract
Type 2 diabetes is a major UK public health priority. Among minority ethnic communities, the prevalence is alarmingly high, approximately three to five times higher than in the white British population. Particularly striking is the earlier onset of Type 2 diabetes, which occurs some 10-12 years younger, with a significant proportion of cases being diagnosed before the age of 40 years. This review focuses on the UK context and Type 2 diabetes in adult populations, exploring the available evidence regarding the complex interplay of biological, lifestyle, social, clinical and healthcare system factors that are known to drive these disparities.
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Affiliation(s)
- L M Goff
- Diabetes Research Group, Departments of Diabetes and Nutritional Sciences, King's College London, London, UK
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20
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Ethnic distinctions in the pathophysiology of type 2 diabetes: a focus on black African-Caribbean populations. Proc Nutr Soc 2019; 79:184-193. [PMID: 31307560 DOI: 10.1017/s0029665119001034] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Type 2 diabetes (T2D) is a global public health priority, particularly for populations of black African-Caribbean ethnicity, who suffer disproportionately high rates of the disease. While the mechanisms underlying the development of T2D are well documented, there is growing evidence describing distinctions among black African-Caribbean populations. In the present paper, we review the evidence describing the impact of black African-Caribbean ethnicity on T2D pathophysiology. Ethnic differences were first recognised through evidence that metabolic syndrome diagnostic criteria fail to detect T2D risk in black populations due to less central obesity and dyslipidaemia. Subsequently more detailed investigations have recognised other mechanistic differences, particularly lower visceral and hepatic fat accumulation and a distinctly hyperinsulinaemic response to glucose stimulation. While epidemiological studies have reported exaggerated insulin resistance in black populations, more detailed and direct measures of insulin sensitivity have provided evidence that insulin sensitivity is not markedly different to other ethnic groups and does not explain the hyperinsulinaemia that is exhibited. These findings lead us to hypothesise that ectopic fat does not play a pivotal role in driving insulin resistance in black populations. Furthermore, we hypothesise that hyperinsulinaemia is driven by lower rates of hepatic insulin clearance rather than heightened insulin resistance and is a primary defect rather than occurring in compensation for insulin resistance. These hypotheses are being investigated in our ongoing South London Diabetes and Ethnicity Phenotyping study, which will enable a more detailed understanding of ethnic distinctions in the pathophysiology of T2D between men of black African and white European ethnicity.
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Bello O, Mohandas C, Shojee-Moradie F, Jackson N, Hakim O, Alberti KGMM, Peacock JL, Umpleby AM, Amiel SA, Goff LM. Black African men with early type 2 diabetes have similar muscle, liver and adipose tissue insulin sensitivity to white European men despite lower visceral fat. Diabetologia 2019; 62:835-844. [PMID: 30729259 PMCID: PMC6450859 DOI: 10.1007/s00125-019-4820-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 12/27/2018] [Indexed: 01/11/2023]
Abstract
AIMS/HYPOTHESIS Type 2 diabetes is more prevalent in black African than white European populations although, paradoxically, black African individuals present with lower levels of visceral fat, which has a known association with insulin resistance. Insulin resistance occurs at a tissue-specific level; however, no study has simultaneously compared whole body, skeletal muscle, hepatic and adipose tissue insulin sensitivity between black and white men. We hypothesised that, in those with early type 2 diabetes, black (West) African men (BAM) have greater hepatic and adipose tissue insulin sensitivity, compared with white European men (WEM), because of their reduced visceral fat. METHODS Eighteen BAM and 15 WEM with type 2 diabetes underwent a two-stage hyperinsulinaemic-euglycaemic clamp with stable glucose and glycerol isotope tracers to assess tissue-specific insulin sensitivity and a magnetic resonance imaging scan to assess body composition. RESULTS We found no ethnic differences in whole body, skeletal muscle, hepatic or adipose tissue insulin sensitivity between BAM and WEM. This finding occurred in the presence of lower visceral fat in BAM (3.72 vs 5.68 kg [mean difference -1.96, 95% CI -3.30, 0.62]; p = 0.01). There was an association between skeletal muscle and adipose tissue insulin sensitivity in WEM that was not present in BAM (r = 0.78, p < 0.01 vs r = 0.25 p = 0.37). CONCLUSIONS/INTERPRETATION Our data suggest that in type 2 diabetes there are no ethnic differences in whole body, skeletal muscle, hepatic and adipose tissue insulin sensitivity between black and white men, despite differences in visceral adipose tissue, and that impaired lipolysis may not be contributing to skeletal muscle insulin resistance in men of black African ethnicity.
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Affiliation(s)
- Oluwatoyosi Bello
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, Franklin-Wilkins Building, Waterloo Campus, London, SE1 9NH, UK
| | - Cynthia Mohandas
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, Franklin-Wilkins Building, Waterloo Campus, London, SE1 9NH, UK
| | | | - Nicola Jackson
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Olah Hakim
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, Franklin-Wilkins Building, Waterloo Campus, London, SE1 9NH, UK
| | - K George M M Alberti
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, Franklin-Wilkins Building, Waterloo Campus, London, SE1 9NH, UK
| | - Janet L Peacock
- School of Population Health and Environmental Sciences, King's College London, London, UK
| | - A Margot Umpleby
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Stephanie A Amiel
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, Franklin-Wilkins Building, Waterloo Campus, London, SE1 9NH, UK
| | - Louise M Goff
- Department of Diabetes, School of Life Course Sciences, Faculty of Life Sciences & Medicine, King's College London, Franklin-Wilkins Building, Waterloo Campus, London, SE1 9NH, UK.
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22
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Mtintsilana A, Micklesfield LK, Chorell E, Olsson T, Goedecke JH. Fat redistribution and accumulation of visceral adipose tissue predicts type 2 diabetes risk in middle-aged black South African women: a 13-year longitudinal study. Nutr Diabetes 2019; 9:12. [PMID: 30918247 PMCID: PMC6437211 DOI: 10.1038/s41387-019-0079-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Revised: 03/08/2019] [Accepted: 03/12/2019] [Indexed: 01/30/2023] Open
Abstract
Background Cross-sectional studies in South Africa (SA) have shown that black SA women, despite being more insulin resistant, have less visceral adipose tissue (VAT) and more subcutaneous adipose tissue (SAT) than white women. This study aimed to investigate whether baseline and/or change in body fat and its distribution predict type 2 diabetes (T2D) risk in middle-aged black SA women, 13 years later. Methods We studied 142 black SA women who are the caregivers of the Birth-to-Twenty plus cohort, and who had normal glucose tolerance (NGT) at baseline. At baseline and follow-up, fasting blood samples, basic anthropometry and dual-energy X-ray absorptiometry-derived body composition were measured. At follow-up, an oral glucose tolerance test was completed. The WHO diabetes diagnostic criteria were used to define NGT, impaired fasting glucose (IFG)/impaired glucose tolerance (IGT), impaired glucose metabolism (IGM) and T2D. Results At follow-up, 64% of participants remained NGT, whereas 25% developed IGM, and 11% developed T2D. The IGM and the T2D groups were combined for statistical analyses. At baseline, trunk fat mass (FM), VAT but not SAT (measures of central FM) were higher in the IGM/T2D group than the NGT group (p < 0.0001). In contrast, the IGM/T2D group had lower leg %FM at baseline than the NGT group (p < 0.0001). Baseline trunk FM (Odds ratio per 1 kg increase (95% confidence interval, 1.95 (1.43–2.67))), and VAT (OR per 10 cm2 increase, 1.25 (1.10–1.42)), and the change in VAT (1.12 (1.03–1.23)) were associated with greater odds of developing IGM/T2D, whereas baseline leg FM (OR per 1 kg increase, 0.55 (0.41–0.73)) were associated with reduced IGM/T2D risk at follow-up (p < 0.05). Conclusions Relative fat redistribution, with VAT accumulation, predicted the development of IGM/T2D 13 years before its onset. Prevention of central obesity is a key factor to reduce the risk of developing T2D among middle-aged urban black SA women.
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Affiliation(s)
- Asanda Mtintsilana
- South African Medical Research Council/University of the Witwatersrand Developmental Pathways for Health Research Unit, Department of Paediatrics, University of Witwatersrand, Johannesburg, South Africa
| | - Lisa K Micklesfield
- South African Medical Research Council/University of the Witwatersrand Developmental Pathways for Health Research Unit, Department of Paediatrics, University of Witwatersrand, Johannesburg, South Africa
| | - Elin Chorell
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
| | - Tommy Olsson
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
| | - Julia H Goedecke
- South African Medical Research Council/University of the Witwatersrand Developmental Pathways for Health Research Unit, Department of Paediatrics, University of Witwatersrand, Johannesburg, South Africa. .,Non-Communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa.
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23
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Raygor V, Abbasi F, Lazzeroni LC, Kim S, Ingelsson E, Reaven GM, Knowles JW. Impact of race/ethnicity on insulin resistance and hypertriglyceridaemia. Diab Vasc Dis Res 2019; 16:153-159. [PMID: 31014093 PMCID: PMC6713231 DOI: 10.1177/1479164118813890] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
OBJECTIVE Insulin sensitivity affects plasma triglyceride concentration and both differ by race/ethnicity. The purpose of this study was to provide a comprehensive assessment of the variation in insulin sensitivity and its relationship to hypertriglyceridaemia between five race/ethnic groups. RESEARCH DESIGN AND METHODS In this cross-sectional study, clinical data for 1025 healthy non-Hispanic White, Hispanic White, East Asian, South Asian and African American individuals were analysed. Insulin-mediated glucose disposal (a direct measure of peripheral insulin sensitivity) was measured using the modified insulin suppression test. Statistical analysis was performed using analysis of co-variance. RESULTS Of the study participants, 63% were non-Hispanic White, 9% were Hispanic White, 11% were East Asian, 11% were South Asian and 6% were African American. Overall, non-Hispanic Whites and African Americans displayed greater insulin sensitivity than East Asians and South Asians. Triglyceride concentration was positively associated with insulin resistance in all groups, including African Americans. Nevertheless, for any given level of insulin sensitivity, African Americans had the lowest triglyceride concentrations. CONCLUSION Insulin sensitivity, as assessed by a direct measure of insulin-mediated glucose disposal, and its relationship to triglyceride concentration vary across five race/ethnic groups. Understanding these relationships is crucial for accurate cardiovascular risk stratification and prevention.
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Affiliation(s)
- Viraj Raygor
- Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Fahim Abbasi
- Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Laura C Lazzeroni
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA, USA
- Department of Biomedical Data Science, Stanford University School of Medicine, Stanford, CA, USA
| | - Sun Kim
- Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
- Diabetes Research Center, Stanford University School of Medicine, Stanford, CA, USA
| | - Erik Ingelsson
- Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
- Diabetes Research Center, Stanford University School of Medicine, Stanford, CA, USA
- Cardiovascular Medicine, Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Gerald M Reaven
- Diabetes Research Center, Stanford University School of Medicine, Stanford, CA, USA
- Cardiovascular Medicine, Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Joshua W Knowles
- Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
- Diabetes Research Center, Stanford University School of Medicine, Stanford, CA, USA
- Cardiovascular Medicine, Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA
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24
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Yang J, Zhang LJ, Wang F, Hong T, Liu Z. Molecular imaging of diabetes and diabetic complications: Beyond pancreatic β-cell targeting. Adv Drug Deliv Rev 2019; 139:32-50. [PMID: 30529307 DOI: 10.1016/j.addr.2018.11.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 09/28/2018] [Accepted: 11/27/2018] [Indexed: 12/13/2022]
Abstract
Diabetes is a chronic non-communicable disease affecting over 400 million people worldwide. Diabetic patients are at a high risk of various complications, such as cardiovascular, renal, and other diseases. The pathogenesis of diabetes (both type 1 and type 2 diabetes) is associated with a functional impairment of pancreatic β-cells. Consequently, most efforts to manage and prevent diabetes have focused on preserving β-cells and their function. Advances in imaging techniques, such as magnetic resonance imaging, magnetic resonance spectroscopy, positron emission tomography, and single-photon-emission computed tomography, have enabled noninvasive and quantitative detection and characterization of the population and function of β-cells in vivo. These advantages aid in defining and monitoring the progress of diabetes and determining the efficacy of anti-diabetic therapies. Beyond β-cell targeting, molecular imaging of biomarkers associated with the development of diabetes, e.g., lymphocyte infiltration, insulitis, and metabolic changes, may also be a promising strategy for early detection of diabetes, monitoring its progression, and occurrence of complications, as well as facilitating exploration of new therapeutic interventions. Moreover, molecular imaging of glucose uptake, production and excretion in specified tissues is critical for understanding the pathogenesis of diabetes. In the current review, we summarize and discuss recent advances in noninvasive imaging technologies for imaging of biomarkers beyond β-cells for early diagnosis of diabetes, investigation of glucose metabolism, and precise diagnosis and monitoring of diabetic complications for better management of diabetic patients.
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Affiliation(s)
- Jichun Yang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences Peking University Health Science Center, Key Laboratory of Cardiovascular Science of the Ministry of Education, Center for Non-coding RNA Medicine, Beijing 100191, China.
| | - Long Jiang Zhang
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China
| | - Fan Wang
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Tianpei Hong
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing 100191, China.
| | - Zhaofei Liu
- Medical Isotopes Research Center and Department of Radiation Medicine, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China.
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Chung ST, Courville AB, Onuzuruike AU, Galvan-De La Cruz M, Mabundo LS, DuBose CW, Kasturi K, Cai H, Gharib AM, Walter PJ, Garraffo HM, Chacko S, Haymond MW, Sumner AE. Gluconeogenesis and risk for fasting hyperglycemia in Black and White women. JCI Insight 2018; 3:121495. [PMID: 30232289 DOI: 10.1172/jci.insight.121495] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 08/14/2018] [Indexed: 12/24/2022] Open
Abstract
Black women, compared with White women, have high rates of whole-body insulin resistance but a lower prevalence of fasting hyperglycemia and hepatic steatosis. This dissociation of whole-body insulin resistance from fasting hyperglycemia may be explained by racial differences in gluconeogenesis, hepatic fat, or tissue-specific insulin sensitivity. Two groups of premenopausal federally employed women, without diabetes were studied. Using stable isotope tracers, [2H2O] and [6,62-H2]glucose, basal glucose production was partitioned into its components (gluconeogenesis and glycogenolysis) and basal whole-body lipolysis ([2H5]glycerol) was measured. Indices of insulin sensitivity, whole-body (SI), hepatic (HISIGPR), and adipose tissue, were calculated. Hepatic fat was measured by proton magnetic resonance spectroscopy. Black women had less hepatic fat and lower fractional and absolute gluconeogenesis. Whole-body SI, HISIGPR, and adipose tissue sensitivity were similar by race, but at any given level of whole-body SI, Black women had higher HISIGPR. Therefore, fasting hyperglycemia may be a less common early pathological feature of prediabetes in Black women compared with White women, because gluconeogenesis remains lower despite similar whole-body SI.
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Affiliation(s)
- Stephanie T Chung
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland, USA
| | | | - Anthony U Onuzuruike
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland, USA
| | - Mirella Galvan-De La Cruz
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland, USA
| | - Lilian S Mabundo
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland, USA
| | - Christopher W DuBose
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland, USA
| | - Kannan Kasturi
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, Maryland, USA
| | - Hongyi Cai
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland, USA
| | - Ahmed M Gharib
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland, USA
| | - Peter J Walter
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland, USA
| | - H Martin Garraffo
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland, USA
| | - Shaji Chacko
- Department of Pediatrics, Children's Nutrition Research Center, US Department of Agriculture/Agricultural Research Service, Baylor College of Medicine, Houston, Texas, USA
| | - Morey W Haymond
- Department of Pediatrics, Children's Nutrition Research Center, US Department of Agriculture/Agricultural Research Service, Baylor College of Medicine, Houston, Texas, USA
| | - Anne E Sumner
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland, USA.,National Institute of Minority Health and Health Disparities, NIH, Bethesda, Maryland, USA
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Trouwborst I, Bowser SM, Goossens GH, Blaak EE. Ectopic Fat Accumulation in Distinct Insulin Resistant Phenotypes; Targets for Personalized Nutritional Interventions. Front Nutr 2018; 5:77. [PMID: 30234122 PMCID: PMC6131567 DOI: 10.3389/fnut.2018.00077] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 08/15/2018] [Indexed: 12/13/2022] Open
Abstract
Cardiometabolic diseases are one of the leading causes for disability and mortality in the Western world. The prevalence of these chronic diseases is expected to rise even further in the next decades. Insulin resistance (IR) and related metabolic disturbances are linked to ectopic fat deposition, which is the storage of excess lipids in metabolic organs such as liver and muscle. Notably, a vicious circle exists between IR and ectopic fat, together increasing the risk for the development of cardiometabolic diseases. Nutrition is a key-determining factor for both IR and ectopic fat deposition. The macronutrient composition of the diet may impact metabolic processes related to ectopic fat accumulation and IR. Interestingly, however, the metabolic phenotype of an individual may determine the response to a certain diet. Therefore, population-based nutritional interventions may not always lead to the most optimal (cardiometabolic) outcomes at the individual level, and differences in the metabolic phenotype may underlie conflicting findings related to IR and ectopic fat in dietary intervention studies. Detailed metabolic phenotyping will help to better understand the complex relationship between diet and metabolic regulation, and to optimize intervention outcomes. A subgroup-based approach that integrates, among others, tissue-specific IR, cardiometabolic parameters, anthropometrics, gut microbiota, age, sex, ethnicity, and psychological factors may thereby increase the efficacy of dietary interventions. Nevertheless, the implementation of more personalized nutrition may be complex, costly, and time consuming. Future studies are urgently warranted to obtain insight into a more personalized approach to nutritional interventions, taking into account the metabolic phenotype to ultimately improve insulin sensitivity and reduce the risk for cardiometabolic diseases.
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Affiliation(s)
- Inez Trouwborst
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, Netherlands
| | - Suzanne M Bowser
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, Netherlands
| | - Gijs H Goossens
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, Netherlands
| | - Ellen E Blaak
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, Netherlands
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27
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The association between high-sensitivity C-reactive protein and metabolic risk factors in black and white South African women: a cross-sectional study. BMC OBESITY 2018; 5:14. [PMID: 29760934 PMCID: PMC5937032 DOI: 10.1186/s40608-018-0191-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 04/22/2018] [Indexed: 11/10/2022]
Abstract
Background High-sensitivity C-reactive protein (hsCRP) is associated with metabolic risk, however it is unclear whether the relationship is confounded by racial/ethnic differences in socioeconomic status (SES), lifestyle factors or central adiposity. The aims of the study was, (1) to investigate whether hsCRP levels differ by race/ethnicity; (2) to examine the race/ethnic-specific associations between hsCRP, HOMA-IR and serum lipids [total cholesterol (TC), triglycerides (TG), high-density lipoproteins (HDL-C) and low-density lipoproteins (LDL-C)]; and (3) to determine whether race/ethnic-specific associations are explained by SES, lifestyle factors or waist circumference (WC). Methods The convenience sample comprised 195 black and 153 white apparently health women, aged 18-45 years. SES (education, assets and housing density) and lifestyle factors (alcohol use, physical activity and contraceptive use) were collected by questionnaire. Weight, height and WC were measured, and fasting blood samples collected for hsCRP, glucose, insulin, and lipids. Results Black women had higher age- and BMI-adjusted hsCRP levels than white women (p = 0.047). hsCRP was associated with HOMA-IR (p < 0.001), TG (p < 0.001), TC (p < 0.05), HDL-C (p < 0.05), and LDL-C (p < 0.05), independent of age and race/ethnicity. The association between hsCRP and lipids differed by race/ethnicity, such that hsCRP was positively associated with TG and LDL-C in white women, and inversely associated with HDL-C in black women. Higher hsCRP was also associated with higher TC in white women and lower TC in black women. Furthermore, when adjusting for SES and lifestyle factors, the associations between hsCRP, and TC and TG, remained, however the associations between hsCRP, and HDL-C and LDL-C, were no longer significant. Conclusion Although circulating hsCRP may identify individuals at increased metabolic risk, the heterogeneity in these associations between racial/ethnic groups highlights the need for prospective studies investigating the role of hsCRP for risk prediction in different populations.
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28
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Goedecke JH, Mendham AE, Clamp L, Nono Nankam PA, Fortuin-de Smidt MC, Phiri L, Micklesfield LK, Keswell D, Woudberg NJ, Lecour S, Alhamud A, Kaba M, Lutomia FM, van Jaarsveld PJ, de Villiers A, Kahn SE, Chorell E, Hauksson J, Olsson T. An Exercise Intervention to Unravel the Mechanisms Underlying Insulin Resistance in a Cohort of Black South African Women: Protocol for a Randomized Controlled Trial and Baseline Characteristics of Participants. JMIR Res Protoc 2018; 7:e75. [PMID: 29669711 PMCID: PMC5932332 DOI: 10.2196/resprot.9098] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 11/20/2017] [Accepted: 11/20/2017] [Indexed: 11/13/2022] Open
Abstract
Background The pathogenesis of type 2 diabetes (T2D) in black African women is complex and differs from that in their white counterparts. However, earlier studies have been cross-sectional and provide little insight into the causal pathways. Exercise training is consistently used as a model to examine the mechanisms underlying insulin resistance and risk for T2D. Objective The objective of the study was to examine the mechanisms underlying the changes in insulin sensitivity and secretion in response to a 12-week exercise intervention in obese black South African (SA) women. Methods A total of 45 obese (body mass index, BMI: 30-40 kg/m2) black SA women were randomized into a control (n=22) or experimental (exercise; n=23) group. The exercise group completed 12 weeks of supervised combined aerobic and resistance training (40-60 min, 4 days/week), while the control group maintained their typical physical activity patterns, and both groups were requested not to change their dietary patterns. Before and following the 12-week intervention period, insulin sensitivity and secretion (frequently sampled intravenous glucose tolerance test) and its primary and secondary determinants were measured. Dietary intake, sleep quality and quantity, physical activity, and sedentary behaviors were measured every 4 weeks. Results The final sample included 20 exercise and 15 control participants. Baseline sociodemographics, cardiorespiratory fitness, anthropometry, cardiometabolic risk factors, physical activity, and diet did not differ between the groups (P>.05). Conclusions The study describes a research protocol for an exercise intervention to understand the mechanisms underlying insulin sensitivity and secretion in obese black SA women and aims to identify causal pathways underlying the high prevalence of insulin resistance and risk for T2D in black SA women, targeting specific areas for therapeutic intervention. Trial Registration Pan African Clinical Trial Registry PACTR201711002789113; http://www.pactr.org/ATMWeb/ appmanager/atm/atmregistry?_nfpb=true&_pageLabel=portals_app_atmregistry_portal_page_13 (Archived by WebCite at http://www.webcitation.org/6xLEFqKr0)
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Affiliation(s)
- Julia H Goedecke
- Non-Communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa.,Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
| | - Amy E Mendham
- Non-Communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa.,Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
| | - Louise Clamp
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
| | - Pamela A Nono Nankam
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
| | - Melony C Fortuin-de Smidt
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
| | - Lindokuhle Phiri
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
| | - Lisa K Micklesfield
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa.,South African Medical Research Council / University of the Witwatersrand Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Gauteng, South Africa
| | - Dheshnie Keswell
- Division of Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa
| | - Nicholas J Woudberg
- Hatter Institute for Cardiovascular Research in Africa, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Sandrine Lecour
- Hatter Institute for Cardiovascular Research in Africa, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Ali Alhamud
- Division of Biomedical Engineering, Department of Human Biology, University of Cape Town, Cape Town, South Africa
| | - Mamadou Kaba
- Division of Medical Microbiology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Faith M Lutomia
- Division of Medical Microbiology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Paul J van Jaarsveld
- Non-Communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa.,Division of Medical Physiology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Anniza de Villiers
- Non-Communicable Diseases Research Unit, South African Medical Research Council, Cape Town, South Africa
| | - Steven E Kahn
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, Veterans Affairs Puget Sound Health Care System and University of Washington, Seattle, WA, United States
| | - Elin Chorell
- Department of Public Health and Clinical Medicine, Umeå University, Umea, Sweden
| | - Jon Hauksson
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
| | - Tommy Olsson
- Department of Public Health and Clinical Medicine, Umeå University, Umea, Sweden
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29
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Boyer WR, Churilla JR, Ehrlich SF, Crouter SE, Hornbuckle LM, Fitzhugh EC. Protective role of physical activity on type 2 diabetes: Analysis of effect modification by race-ethnicity. J Diabetes 2018; 10:166-178. [PMID: 28544478 PMCID: PMC5701882 DOI: 10.1111/1753-0407.12574] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 05/03/2017] [Accepted: 05/21/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND It is well known physical activity (PA) plays a role in the prevention of type 2 diabetes (T2D). However, the extent to which PA may affect T2D risk among different race-ethnic groups is unknown. Therefore, the aim of the present study was to systematically examine the effect modification of race-ethnicity on PA and T2D. METHODS The PubMed and Embase databases were systematically searched through June 2016. Study assessment for inclusion was conducted in three phases: title review (n = 13 022), abstract review (n = 2200), and full text review (n = 265). In all, 27 studies met the inclusion criteria and were used in the analysis. Relative risks (RRs) and 95% confidence intervals (CIs) were extracted and analyzed using Comprehensive Meta-Analysis software. All analyses used a random-effects model. RESULTS A significant protective summary RR, comparing the most active group with the least active PA group, was found for non-Hispanic White (RR 0.71, 95% CI 0.60-0.85), Asians (RR 0.76, 95% CI 0.67-0.85), Hispanics (RR 0.75, 95% CI 0.64-0.89), and American Indians (RR 0.73, 95% CI 0.60-0.88). The summary effect for non-Hispanic Blacks (RR 0.91, 95% CI 0.76-1.08) was not significant. CONCLUSIONS The results of the present study indicate that PA (comparing most to least active groups) provides significant protection from T2D, with the exception of non-Hispanic Blacks. The results also indicate a need for race-ethnicity-specific reporting of RRs in prospective cohort studies that incorporate multiethnic samples.
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Affiliation(s)
- William R. Boyer
- University of Tennessee, Dept. of Kinesiology, Recreation and Sports Studies, Knoxville, TN
| | - James R. Churilla
- University of North Florida, Dept. of Clinical and Applied Movement Sciences, Jacksonville, FL
| | | | - Scott E. Crouter
- University of Tennessee, Dept. of Kinesiology, Recreation and Sports Studies, Knoxville, TN
| | - Lyndsey M. Hornbuckle
- University of Tennessee, Dept. of Kinesiology, Recreation and Sports Studies, Knoxville, TN
| | - Eugene C. Fitzhugh
- University of Tennessee, Dept. of Kinesiology, Recreation and Sports Studies, Knoxville, TN
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Bril F, Portillo-Sanchez P, Liu IC, Kalavalapalli S, Dayton K, Cusi K. Clinical and Histologic Characterization of Nonalcoholic Steatohepatitis in African American Patients. Diabetes Care 2018; 41:187-192. [PMID: 29133343 DOI: 10.2337/dc17-1349] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 10/18/2017] [Indexed: 02/03/2023]
Abstract
OBJECTIVE There has been a widespread misconception among physicians that African Americans are protected from developing nonalcoholic steatohepatitis (NASH). However, a formal histologic and metabolic comparison against well-matched Caucasians has never been performed. RESEARCH DESIGN AND METHODS Sixty-seven African American patients were matched 2:1 to Caucasians (n = 134) for age, sex, BMI, hemoglobin A1c, and prevalence of type 2 diabetes mellitus (T2DM). Screening for NASH included measurement of intrahepatic triglyceride content by proton MRS (1H-MRS), followed by a liver biopsy if patients had hepatic steatosis. Insulin resistance was estimated during an oral glucose tolerance test using the Matsuda Index. RESULTS Compared with Caucasians, African American patients had a lower intrahepatic triglyceride content (mean ± SD 6.1 ± 6.8% vs. 9.4 ± 7.5%, P = 0.007) and the presence of nonalcoholic fatty liver disease (NAFLD) was less common (25.0% vs. 51.9%, P = 0.003). However, prevalence of NASH was not different between ethnicities in patients with NAFLD (57.1% vs. 73.3%, P = 0.12). Moreover, they showed similar severity in each of the individual histologic parameters (inflammation, ballooning, and fibrosis). Among patients with NAFLD, insulin resistance was similar between both ethnic groups (Matsuda Index: 3.3 ± 1.8 vs. 3.1 ± 1.9, P = 0.61; adipose tissue insulin resistance [Adipo-IR] index: 5.7 ± 4.6 vs. 6.4 ± 4.7 mmol/L ⋅ µU/mL, P = 0.53) but appeared to be worse in African American versus Caucasian patients without NAFLD (Matsuda Index: 4.9 ± 3.6 vs. 7.0 ± 4.9, P = 0.11; Adipo-IR: 3.9 ± 2.8 vs. 2.7 ± 2.3 mmol/L ⋅ µU/mL, P = 0.06). African American patients also had lower plasma triglycerides and higher HDL cholesterol, independent of the severity of intrahepatic triglyceride. CONCLUSIONS Although African Americans have lower intrahepatic triglyceride accumulation, once NAFLD develops, NASH occurs as frequently, and as severe, as in Caucasian patients. Therefore, African Americans with NAFLD should be screened for NASH with the same degree of clinical resolve as in Caucasian patients.
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Affiliation(s)
- Fernando Bril
- Division of Endocrinology, Diabetes & Metabolism, University of Florida, Gainesville, FL.,Malcom Randall Veterans Administration Medical Center, Gainesville, FL
| | - Paola Portillo-Sanchez
- Division of Endocrinology, Diabetes & Metabolism, University of Florida, Gainesville, FL
| | - I-Chia Liu
- Division of Endocrinology, Diabetes & Metabolism, University of Florida, Gainesville, FL
| | - Srilaxmi Kalavalapalli
- Division of Endocrinology, Diabetes & Metabolism, University of Florida, Gainesville, FL
| | - Kristin Dayton
- Division of Pediatric Endocrinology, University of Florida, Gainesville, FL
| | - Kenneth Cusi
- Division of Endocrinology, Diabetes & Metabolism, University of Florida, Gainesville, FL .,Malcom Randall Veterans Administration Medical Center, Gainesville, FL
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31
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Utumatwishima JN, Chung ST, Bentley AR, Udahogora M, Sumner AE. Reversing the tide - diagnosis and prevention of T2DM in populations of African descent. Nat Rev Endocrinol 2018; 14:45-56. [PMID: 29052590 DOI: 10.1038/nrendo.2017.127] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Populations of African descent are at the forefront of the worldwide epidemic of type 2 diabetes mellitus (T2DM). The burden of T2DM is amplified by diagnosis after preventable complications of the disease have occurred. Earlier detection would result in a reduction in undiagnosed T2DM, more accurate statistics, more informed resource allocation and better health. An underappreciated factor contributing to undiagnosed T2DM in populations of African descent is that screening tests for hyperglycaemia, specifically, fasting plasma glucose and HbA1c, perform sub-optimally in these populations. To offset this problem, combining tests or adding glycated albumin (a nonfasting marker of glycaemia), might be the way forward. However, differences in diet, exercise, BMI, environment, gene-environment interactions and the prevalence of sickle cell trait mean that neither diagnostic tests nor interventions will be uniformly effective in individuals of African, Caribbean or African-American descent. Among these three populations of African descent, intensive lifestyle interventions have been reported in only the African-American population, in which they have been found to provide effective primary prevention of T2DM but not secondary prevention. Owing to a lack of health literacy and poor glycaemic control in Africa and the Caribbean, customized lifestyle interventions might achieve both secondary and primary prevention. Overall, diagnosis and prevention of T2DM requires innovative strategies that are sensitive to the diversity that exists within populations of African descent.
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Affiliation(s)
- Jean N Utumatwishima
- Section on Ethnicity and Health, Diabetes, Endocrinology and Obesity Branch, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health (NIH), 9000 Rockville Pike, Bethesda, Maryland 20892, USA
| | - Stephanie T Chung
- Section on Ethnicity and Health, Diabetes, Endocrinology and Obesity Branch, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health (NIH), 9000 Rockville Pike, Bethesda, Maryland 20892, USA
| | - Amy R Bentley
- Center for Research on Genomics and Global Health, National Human Genome Research Institute, National Institutes of Health (NIH), 9000 Rockville Pike, Bethesda, Maryland 20892, USA
| | - Margaret Udahogora
- Dietetics Program, University of Maryland, College Park, 0112 Skinner Building, Office 0125 Skinner Building, College Park, Maryland 20742, USA
| | - Anne E Sumner
- Section on Ethnicity and Health, Diabetes, Endocrinology and Obesity Branch, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health (NIH), 9000 Rockville Pike, Bethesda, Maryland 20892, USA
- National Institute of Minority Health and Health Disparities, National Institutes of Health (NIH), 9000 Rockville Pike, Bethesda, Maryland 20892, USA
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Browning MG, Khoraki J, DeAntonio JH, Mazzini G, Mangino MJ, Siddiqui MS, Wolfe LG, Campos GM. Protective effect of black relative to white race against non-alcoholic fatty liver disease in patients with severe obesity, independent of type 2 diabetes. Int J Obes (Lond) 2017; 42:926-929. [PMID: 29437160 DOI: 10.1038/ijo.2017.309] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 11/16/2017] [Accepted: 11/26/2017] [Indexed: 12/15/2022]
Abstract
Severe obesity (body mass index ⩾35 kg m-2) and type 2 diabetes (T2D) are potent and additive risk factors for non-alcoholic fatty liver disease (NAFLD), including non-alcoholic steatohepatitis (NASH). Scant available evidence indicates that black relative to white patients with severe obesity are less susceptible to NAFLD, but it is unclear if T2D abolishes this apparent racial disparity. Therefore, we compared biopsy-proven NAFLD and its progression between black (n=71) and white (n=155) patients with severe obesity stratified by presence or absence of T2D. Although prevalence of T2D was similar between races (37%, P>0.9), whites were significantly more likely than blacks to have NAFLD, NASH and advanced fibrosis (defined as bridging fibrosis and/or cirrhosis). Importantly, T2D was associated with increased odds of NAFLD, NASH and advanced fibrosis (defined as bridging fibrosis or cirrhosis) in whites only (P<0.05). In turn, a higher proportion of blacks than whites with T2D were free of NAFLD (58 versus 22%, P<0.01). These preliminary findings question translation of the powerful interconnection between T2D and NAFLD in whites with severe obesity to blacks and point to an important role of race in the pathophysiology and treatment of these diseases.
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Affiliation(s)
- M G Browning
- Department of Physical Therapy, Virginia Commonwealth University. Richmond, VA, USA
| | - J Khoraki
- Department of Surgery, Virginia Commonwealth University. Richmond, VA, USA
| | - J H DeAntonio
- Department of Surgery, Virginia Commonwealth University. Richmond, VA, USA
| | - G Mazzini
- Department of Surgery, Virginia Commonwealth University. Richmond, VA, USA
| | - M J Mangino
- Department of Surgery, Virginia Commonwealth University. Richmond, VA, USA
| | - M S Siddiqui
- Department of Internal Medicine, Virginia Commonwealth University. Richmond, VA, USA
| | - L G Wolfe
- Department of Surgery, Virginia Commonwealth University. Richmond, VA, USA
| | - G M Campos
- Department of Surgery, Virginia Commonwealth University. Richmond, VA, USA
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Goedecke JH, Mtintsilana A, Dlamini SN, Kengne AP. Type 2 diabetes mellitus in African women. Diabetes Res Clin Pract 2017; 123:87-96. [PMID: 28006698 DOI: 10.1016/j.diabres.2016.11.017] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 11/28/2016] [Indexed: 02/08/2023]
Abstract
Compared to global estimates, Sub-Saharan Africa (SSA) has the highest projected rates of increase in type 2 diabetes (T2D) over the next 25years. This is attributed to the ageing population, increasing urbanisation and the associated lifestyle changes. Although the prevalence does not differ by gender, deaths attributable to T2D in SSA are greater in women, likely due to differences in beliefs and access to care. Women in SSA also have greater risk factor burden for T2D than men, in particular obesity, which is explained in part by sociocultural factors. The pathogenesis of diabetes differs between African and Caucasian women, with implications for risk assessment. African women are more insulin resistant than their Caucasian counterparts, despite a more 'favourable' body fat distribution. Notably, women in SSA face the dual burden of T2D and HIV/AIDS. HIV positive women in SSA are typically young and obese, with the latter being exacerbated by anti-retroviral therapy (ART). Cultural perceptions regarding weight loss and limited financial resources are the major limitations to the management of T2D. Hence prevention is vital. However, there is a paucity of studies examining the effectiveness and sustainability of interventions to reduce T2D in SSA.
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Affiliation(s)
- Julia H Goedecke
- Non-Communicable Disease Research Unit, South African Medical Research Council, Cape Town, South Africa.
| | - Asanda Mtintsilana
- Medical Research Council/University of Witwatersrand, Developmental Pathways for Health Research Unit, Department of Paediatrics, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Siphiwe N Dlamini
- Medical Research Council/University of Witwatersrand, Developmental Pathways for Health Research Unit, Department of Paediatrics, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Andre Pascal Kengne
- Non-Communicable Disease Research Unit, South African Medical Research Council, Cape Town, South Africa
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Jean-Luc Gradidge P, Norris SA, Jaff NG, Crowther NJ. Metabolic and Body Composition Risk Factors Associated with Metabolic Syndrome in a Cohort of Women with a High Prevalence of Cardiometabolic Disease. PLoS One 2016; 11:e0162247. [PMID: 27589387 PMCID: PMC5010252 DOI: 10.1371/journal.pone.0162247] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 08/21/2016] [Indexed: 12/18/2022] Open
Abstract
Background The aetiology of the metabolic syndrome and the inter-relationship between risk factors for this syndrome are poorly understood. The purpose of this investigation was to determine the risk factors for metabolic syndrome and their interactions in a cohort of women with a high prevalence of metabolic syndrome. Materials and Methods Abdominal and whole body composition (ultrasound and dual-energy X-ray absorptiometry), blood pressure, and cardiometabolic and demographic factors were measured in a cross-sectional study of 702 black African women from Soweto, Johannesburg. Data was analysed using multivariate logistic regression. Results Metabolic syndrome was present in 49.6% of the study cohort. Logistic regression analysis demonstrated that adiponectin (odds ratio [95% CIs]: 0.84 [0.77, 0.92], p<0.0005) and abdominal subcutaneous fat (0.56 [0.39, 0.79], p = 0.001) reduced metabolic syndrome risk whilst insulin resistance (1.31 [1.16, 1.48], p<0.0005) and trunk fat-free soft-tissue mass (1.34 [1.10, 1.61], p = 0.002) increased risk. Within this group of risk factors, the relationship of adiponectin with metabolic syndrome risk, when analysed across adiponectin hexiles, was the least affected by adjustment for the other risk factors. Conclusions Adiponectin has a significant protective role against metabolic syndrome and is independent of other risk factors. The protective and possible augmentive effects of abdominal subcutaneous fat and lean trunk mass, respectively on metabolic syndrome risk demonstrate the existence of novel interactions between body composition and cardiometabolic disease.
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Affiliation(s)
- Philippe Jean-Luc Gradidge
- Centre for Exercise Science and Sports Medicine (CESSM), Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- MRC/Wits Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- * E-mail:
| | - Shane A. Norris
- MRC/Wits Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Nicole G. Jaff
- MRC/Wits Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Department of Chemical Pathology, National Health Laboratory Service, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Nigel J. Crowther
- Department of Chemical Pathology, National Health Laboratory Service, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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