The current waist circumference cut point used for the diagnosis of metabolic syndrome in sub-Saharan African women is not appropriate

Waist circumference and cardiometabolic parameters in people of African/Caribbean ancestry with HIV in South London (CKD-AFRICA study)

BACKGROUND

There are no validated waist circumference (WC) cut-offs to define metabolic syndrome in Black people with HIV.

METHODS

Cross-sectional analyses within the CKD-AFRICA study. We used Pearson correlation coefficients and receiver operating characteristic (ROC) curves to describe the relationship between WC and cardiometabolic parameters including triglycerides, cholesterol, glucose, glycated haemoglobin (HbA1c), and homeostatic model assessment for insulin resistance (HOMA-IR), and to identify optimal WC cut-offs for each of these outcomes.

RESULTS

We included 383 participants (55% female, median age 52 years) with generally well controlled HIV. Female and male participants had similar WC (median 98 vs. 97 cm, p = .16). Generally weak correlations (r2 < 0.2) between WC and other cardiometabolic parameters were observed, with low (<0.7) areas under the ROC curves. The optimal WC cut-offs for constituents of the metabolic syndrome, HbA1c and HOMA-IR ranged from 92 to 101 cm in women and 89-98 cm in men, respectively; these cut-offs had variable sensitivity (52%-100%) and generally poor specificity (28%-72%).

CONCLUSIONS

In this cohort of Black people with HIV, WC cut-offs for cardiometabolic risk factors in male participants were in line with the recommended value of 94 cm while in female participants they vastly exceeded the recommended 80 cm for white women.

Women´s experiences of menopause: A qualitative study among women in Soweto, South Africa

Women today are experiencing menopause for decades more than in previous generations. This 'change of life' is defined by an entire stage of physical, hormonal, and emotional changes that accompany menstrual irregularity and the cessation of fertility, although limited medical research has focused on it. Yet, the inevitability of menopause is universal for all human females around 50 years old. In this article, we conducted twenty-five 20-60 min semi-structured qualitative interviews. Most women marked menopause by fertility cessation and social transition to old age, pushing back against a medical framework of menopause that emphasises hormonal deficiency and becoming disordered. In contrast, women frame menopause as a natural process that contributes to a critical social role transition, which they perceive as deeply private in part because it is associated with a reduction in femininity, sexuality, and power. On the other hand, menopause was also described as a liberating process through which women no longer needed to purchase pads or manage blood loss. Recognising how women may perceive menopause not as a deficit or disorder but as a social role transition that has both costs and benefits is useful for medical practitioners when discussing clinical options.

Validation of mid-arm circumference for surveillance of obesity in African adolescent girls and adult women

This study aimed to assess the validity of mid-arm circumference (MAC), also known as mid-upper arm circumference (MUAC), for classification of high body fatness in Namibian adolescent girls and women and to test whether classification accuracy of MUAC was higher than the traditional simple proxy for high fatness, the BMI. In 206 adolescent girls aged 13-19 years and 207 adult women aged 20-40 years, we defined obesity conventionally (BMI-for-age Z score ≥ 2·00, adolescents; adults BMI ≥ 30·0 kg/m2) and also defined obesity using published MAC cut-off values. 2H oxide dilution was used to measure total body water (TBW) to define high body fat percentage (≥ 30 % in the adolescents, ≥ 38 % in the adults), and we compared the ability of BMI and MAC to classify high body fatness correctly using sensitivity, specificity and predictive values. In the adolescents, obesity prevalence was 9·2 % (19/206) using BMI-for-age and 63·2 % (131/206) using TBW; sensitivity of BMI-for-age was 14·5 % (95 % CI 9·1, 22·0 %) but was improved significantly using MAC of 22·6 cm (sensitivity 96·9 %; 95 % CI 92·1 %, 99·3 %). In the adults, obesity prevalence was 30·4 % (63/207) using BMI and 57·0 % (118/207) using TBW, and sensitivity of BMI was 52·5 % (95 % CI 43·6, 62·2 %), but using a MAC of 30·6 cm sensitivity was 72·8 % (95 % CI 66·4, 82·6 %). Surveillance of obesity in African adolescent girls and adult women is likely to be improved substantially by use of MAC as an alternative to the BMI-for-age and BMI.

Msolomba V, Venter F, Carmona S, Kao K, Gordon A, Meyer-Rath G. Integration of point-of-care screening for type 2 diabetes mellitus and hypertension with COVID-19 rapid antigen screening in Johannesburg, South Africa

AIMS

We sought to evaluate the yield and linkage-to-care for diabetes and hypertension screening alongside a study assessing the use of rapid antigen tests for COVID-19 in taxi ranks in Johannesburg, South Africa.

METHODS

Participants were recruited from Germiston taxi rank. We recorded results of blood glucose (BG), blood pressure (BP), waist circumference, smoking status, height, and weight. Participants who had elevated BG (fasting ≥7.0; random ≥11.1mmol/L) and/or BP (diastolic ≥90 and systolic ≥140mmHg) were referred to their clinic and phoned to confirm linkage.

RESULTS

1169 participants were enrolled and screened for elevated BG and elevated BP. Combining participants with a previous diagnosis of diabetes (n = 23, 2.0%; 95% CI:1.3-2.9%) and those that had an elevated BG measurement (n = 60, 5.2%; 95% CI:4.1-6.6%) at study enrollment, we estimated an overall indicative prevalence of diabetes of 7.1% (95% CI:5.7-8.7%). When combining those with known hypertension at study enrollment (n = 124, 10.6%; 95% CI:8.9-12.5%) and those with elevated BP (n = 202; 17.3%; 95% CI:15.2-19.5%), we get an overall prevalence of hypertension of 27.9% (95% CI:25.4-30.1%). Only 30.0% of those with elevated BG and 16.3% of those with elevated BP linked-to-care.

CONCLUSION

By opportunistically leveraging existing COVID-19 screening in South Africa to screen for diabetes and hypertension, 22% of participants received a potential new diagnosis. We had poor linkage-to-care following screening. Future research should evaluate options for improving linkage-to-care, and evaluate the large-scale feasibility of this simple screening tool.

Cardiometabolic syndrome among general adult population in Ghana: The role of lipid accumulation product, waist circumference-triglyceride index, and triglyceride-glucose index as surrogate indicators

Background

Visceral obesity and insulin resistance contribute to developing cardiometabolic syndrome (MetS). We investigated the predictive abilities of lipid accumulation product (LAP), waist circumference-triglyceride index (WTI), and triglyceride-glucose (TyG) index for MetS screening among the general Ghanaian adults.

Methods

The final prospective analysis included 4740 healthy adults aged 30-90 years from three communities comprising Ejisu, Konongo, and Ashanti Akim Agogo in Ghana. Self-structured questionnaire pretested was used to collect sociodemographic, anthropometric, and clinical data. Blood samples were taken after fasting to measure glucose and lipid levels. LAP, WTI, and TyG were calculated from standard equations. MetS was defined by the International Diabetes Federation criteria. Receiver operating characteristic (ROC) curves and multivariable logistic regression were utilized to evaluate the potential of the three indices in identifying MetS.

Results

Of the 4740 participants, 39.7% had MetS. MetS was more common in females (50.3%) than in males (22.2%). Overall, LAP ≥ 27.52 yielded as the best index for MetS with the highest area under the ROC curve (AUC) (0.866). At cut-off LAP point of ≥23.87 in males and ≥33.32 in females, an AUC of 0.951 and 0.790 was identified in MetS prediction, respectively. LAP was an independent risk measure of MetS for both males (45.6-fold) and females (3.7-fold) whereas TyG was an independent risk measure for females (3.7-fold) only.

Conclusions

MetS is increasing among the general adult population. LAP and TyG are important sex-specific risk measures to screen for MetS among the general adult population in our cohort.

Pre-morbid cardiometabolic risks among South Africans living in informal settlements

AIM

Numerous studies have been conducted on cardiometabolic risk factors in South Africa. However, not much has been done in informal settlement populations faced with their own set of health risks. This study screened for pre-morbid cardiometabolic risks and associated factors among adults living in informal settlements in South Africa.

METHODS

A cross-sectional study used the WHO STEPwise questionnaire to collect data on demography, anthropometry, blood pressure, and glucose and cholesterol levels (n = 329). Cardiometabolic risks were based on the criteria considered by the International Diabetes Federation and the National Cholesterol Education Program Adult Treatment Panel III. Data were analysed using STATA 14.

RESULTS

The median age of the participants was 35 (25-42) years. Cardiometabolic risk factors among the participants were hypertension (66%), overweight/obesity (45%), abdominal obesity (46%), and elevated cholesterol (15%) and glucose levels (7%). The metabolic syndrome was found in 17% of the participants, with a high prevalence observed among participants aged 35-59 years (28%) and ≥ 60 years (40%). The metabolic syndrome was significantly associated with gender [males, adjusted odds ratio (AOR) = 0.4, 95% CI: 0.20-0.90] and age, 35-59 years (AOR = 5.07, 95% CI: 2.24-11.23) and ≥ 60 years (AOR = 6.57, 95% CI; 1.57-27.54).

CONCLUSIONS

Prevalent cardiometabolic risk factors in informal settlements indicate the need for routine screening for all the components of the metabolic syndrome at the primary healthcare level.

Association of microalbuminuria with serum lipids and inflammatory markers in an adult population in the Dikgale Health and Demographic Surveillance System site, South Africa

BACKGROUND

There is evidence that microalbuminuria (urinary albumin excretion) is an early sign of vascular damage and an established risk factor for cardiovascular morbidity and mortality. This study investigated the magnitude of microalbuminuria and its association with serum lipids and inflammatory markers among a rural black population residing in the Dikgale Health and Demographic Surveillance System site, South Africa.

METHODS

Data were collected from 602 presumably healthy participants (225 men and 377 women) aged ≥ 18 years. Biochemical data collection included serum lipids, glucose, insulin, high-sensitivity C-reactive protein (hs-CRP), urine albumin and creatinine. Anthropometry and blood pressure were also measured. Microalbuminuria was diagnosed with an albumin-creatinine ratio of ≥ 2.5 mg/mmol in men and ≥ 3.5 mg/mmol in women. Data were analysed using SPSS version 22.0.

RESULTS

The mean age of participants was 48.63 ± 20.89 years. High percentages of microalbuminaria (35.7%), high levels of interleukin 6 (17.8%), hs-CRP (32.9%), triglycerides (TG) (26.1%), low-density lipoprotein cholesterol (52.2%) and total cholesterol (32.0%), and low levels of high-density lipoprotein cholesterol (29.1%) were observed in the population. Increased glucose levels (32.8%), insulin resistance (27.6%), hypertension (45.8%), overweight (26.8%) and obesity (25.4%) were also prevalent. Microalbuminuria was associated with high hs-CRP and TG levels in the men (adjusted odds ratios = 9.434, 95% confidence interval: 1.753 - 50.778, p = 0.01).

CONCLUSIONS

High prevalence of microalbuminuria, hypertension, insulin resistance, overweight and obesity, as well as abnormal levels of serum lipids and inflammatory markers were observed in the population. Microalbuminuria was associated with high hs-CRP and TG levels among men.

The Effect of Obesity on the Waist Circumference Cut-Point Used for the Diagnosis of the Metabolic Syndrome in African Women: Results from the SWEET Study

Waist circumference (WC) is one of the diagnostic criteria for metabolic syndrome (MetS). However, studies have shown that the waist cut-point may be influenced by BMI. The aim of this study was to, therefore, determine whether the presence of obesity influences the WC cut-point used to diagnose MetS in sub-Saharan African women. The second aim was to determine whether calculated cut-points of other waist-related and dual-energy X-ray absorptiometry (DXA)-determined anthropometric measures used for the diagnosis of MetS were also influenced by BMI. Biochemical, simple anthropometric and dual-energy X-ray absorptiometry-derived anthropometric data were collected in 702 black South African women from the Study of Women Entering and in Endocrine Transition (SWEET). A receiver operating characteristic curve analysis was used to determine waist, waist-to-hip (WHR) and waist-to-height ratios, body shape index (ABSI), total body fat, trunk fat, and peripheral (arm + leg) fat cut-points for MetS (without waist) in subjects with BMI above or below the median value. The estimated WC cut-points (107 cm, 93.5 cm) for women with high BMI and low BMI, respectively, and the cut-points for the other anthropometric variables for the diagnosis of MetS were greater in high BMI women compared to low BMI women. The exceptions were WHR and ABSI, for which the cut-points were very similar in both BMI groups, and peripheral fat, where the cut-point was lower in the high BMI group. Logistic regression analysis demonstrated that WC was associated with a higher risk (odds ratio [95% CIs]: 1.07 [1.04, 1.10]; p < 0.0001), whilst hip was associated with a lower risk (0.97 [0.94, 0.99]; p = 0.02) for MetS. These data suggest that with increasing BMI, the higher levels of protective gluteofemoral fat lead to the requirement for higher WC cut-points for MetS diagnosis. The opposing associations of waist and hip with MetS risk make WHR a more appropriate variable for diagnosing MetS among African women as the WHR cut-point is less influenced by increasing BMI than is WC, which was also observed for ABSI.

Waist circumference thresholds predicting incident dysglycaemia and type 2 diabetes in Black African men and women

AIMS

To determine the waist circumference (WC) thresholds for the prediction of incident dysglycaemia and type 2 diabetes (T2D) in Black South African (SA) men and women and to compare these to the advocated International Diabetes Federation (IDF) Europid thresholds.

MATERIALS AND METHODS

In this prospective study, Black SA men (n = 502) and women (n = 527) from the Middle-aged Sowetan Cohort study who had normal or impaired fasting glucose at baseline (2011-2015) were followed up until 2017 to 2018. Baseline measurements included anthropometry, blood pressure and fasting glucose, HDL cholesterol and triglyceride concentrations. At follow-up, glucose tolerance was assessed using an oral glucose tolerance test. The Youden index was used to determine the optimal threshold of WC to predict incident dysglycaemia and T2D.

RESULTS

In men, the optimal WC threshold was 96.8 cm for both dysglycaemia and T2D (sensitivity: 56% and 70%; specificity: 74% and 70%, respectively), and had higher specificity (P < 0.001) than the IDF threshold of 94 cm. In women, the optimal WC threshold for incident dysglycaemia was 91.8 cm (sensitivity 86%, specificity 37%) and for T2D it was 95.8 cm (sensitivity 85%, specificity 45%), which had lower sensitivity, but higher specificity to predict incident dysglycaemia and T2D than the IDF threshold of 80 cm (sensitivity: 97% and 100%; specificity: 12% and 11%, respectively)).

CONCLUSIONS

We show for the first time using prospective cohort data from Africa that the IDF Europid WC thresholds are not appropriate for an African population, and show that African-specific WC thresholds perform better than the IDF Europid thresholds to predict incident dysglycaemia and T2D.

The Magnitude of NCD Risk Factors in Ethiopia: Meta-Analysis and Systematic Review of Evidence

Background: Non-communicable Diseases (NCDs) and their risk factors are the leading contributors to morbidity and mortality globally, particularly in low- and middle-income countries including Ethiopia. To date, there has been no synthesis of the literature on the relative prevalence of NCD risk factors in Ethiopia. Methodology: We conducted a systematic review and meta-analysis of primary studies reporting on the prevalence of NCD risk factors in Ethiopia published in English from 2012 to July 2020. Pre-tested NCD search terms were applied to Medline, Embase, Scopus, CINAHL, and Global Health. Three reviewers screened and appraised the quality of the identified papers. Data extraction was conducted using a pilot tested proforma. Meta-analysis was conducted using Stata 16 and pooled prevalence estimated with associated 95% confidence intervals. Clinically heterogeneous studies that did not fulfil the eligibility criteria for meta-analysis were narratively synthesised. I² was used to assess statistical heterogeneity. Results: 47 studies fulfilled the inclusion criteria and contributed 68 NCD risk factor prevalence estimates. Hypertension was the most frequently examined NCD risk factor, with a pooled prevalence of 21% (n = 27 studies). The pooled prevalence percentages for overweight and obesity were 19.2% and 10.3%, respectively (n = 7 studies each), with a combined prevalence of 26.8% (n = 1 study). It was not possible to pool the prevalence of alcohol consumption, smoking, metabolic disorders, or fruit consumption because of heterogeneity across studies. The prevalence of alcohol use, as reported from the included individual studies, ranged from 12.4% to 13.5% (n = 7 studies). More than 90% of participants met the WHO-recommended level of physical activity (n = 5 studies). The prevalence of smoking was highly variable, ranging between 0.8% and 38.6%, as was the prevalence of heavy alcohol drinking (12.4% to 21.1%, n = 6 studies) and metabolic syndrome (4.8% to 9.6%, n = 5 studies). Fruit consumption ranged from 1.5% up to the recommended level, but varied across geographic areas (n = 3 studies). Conclusion and recommendations: The prevalence of NCD risk factors in Ethiopia is relatively high. National NCD risk factor surveillance is required to inform the prioritisation of policies and interventions to reduce the NCD burden in Ethiopia.

Biomarkers of Endothelial Activation in Black South African HIV-Positive Subjects are Associated with Both High Viral Load and Low CD4 Counts

The prevalence of cardiovascular death in the HIV-infected population is higher than in uninfected individuals. Growing evidence suggests that HIV infection itself is directly linked to endothelial activation and dysfunction. Therefore, the aim of this study was to investigate whether endothelial activation is present in African subjects with HIV infection and identify its possible determinants. Eighty HIV-infected treatment-naive cases, categorized into two groups based on CD4 count (38 subjects with CD4 count ≤350 cells/mm³ and 42 subjects with CD4 count >350 cells/mm³), were compared with 60 HIV-uninfected controls. A small subgroup of the HIV-infected participants (n = 13) were followed up for 18 months following initiation of antiretroviral therapy (ART). Anthropometric data, fasting lipid and glucose levels, viral load, and CD4 counts were measured as were serum levels of intercellular adhesion molecule-1 (ICAM-1), endothelial leukocyte adhesion molecule-1, vascular cell adhesion molecule-1 (VCAM-1), monocyte chemoattractant protein-1, von Willebrand factor (vWF), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), and interleukin-8 (IL-8). The HIV-infected low CD4 group had higher levels of ICAM-1 (p < .05), VCAM-1 (p < .0005), TNF-α (p < .005), and vWF (p < .005), compared with the controls. In the HIV-infected cohort, VCAM-1 levels were negatively associated with CD4 counts (β = -0.474; p < .0005), whereas vWF levels were positively associated with viral load (β = 0.344; p < .01). Levels of ICAM-1 and VCAM-1 were reduced by ART (p < .05 vs. baseline for both), however, levels of IL-6, IL-8, and TNF-α increased (p < .005 vs. baseline for all). Endothelial activation and inflammation are evident in African ART-naive HIV-infected patients; the former is attenuated, and the latter is increased after 18 months of ART. In HIV-infected subjects, both immunological dysregulation and viral load are associated with biomarkers of endothelial activation.

Pancreatic ductal adenocarcinoma: Prognostic indicators of advanced disease

BACKGROUND/OBJECTIVES

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy associated with high metastatic risk. Prognosis remains poor even after resection. Previously our group identified biomarkers that improved diagnostic accuracy in PDAC beyond the established diagnostic tumour marker, CA19-9. Risk factors, symptoms and circulating biomarkers associated with a PDAC diagnosis may differ from those that alter disease progression and metastasis. This study aimed at assessing the risk factors, presenting symptoms and potential prognostic biomarkers in PDAC and determine their relationship with PDAC stage and/or metastatic status.

METHODS

Seventy-two PDAC patients with imaging available for TNM staging at presentation were enrolled following informed consent. Demographic and clinical data were captured. Blood was collected and 38 cytokines/angiogenic factors measured. Nonparametric association tests, univariate and multivariate logistic regression were performed using STATA version 14.2. A p-value≤0.05 was considered significant and odds ratios reported for effect size.

RESULTS

Most risk factors and symptoms did not differ across the stages of cancer. Although male gender and smoking are risk factors for PDAC, the majority of study patients with metastatic PDAC were non-smoking females. In addition to CA19-9, the platelet count (p<0.01), IL-15 (p = 0.02) and GM-CSF (p<0.01) were significant, independent negative predictors of metastatic PDAC. Moreover, using specific cut-off values in a combined panel, the odds in a patient with all three biomarker levels below the cut-offs is 21 times more likely to have metastatic PDAC (p<0.0001).

CONCLUSIONS

Platelet count, IL-15 and GM-CSF are potential prognostic indicators of metastatic disease in PDAC patients from our local South African population.

The optimal WC cut-off points for the prediction of subclinical CVD as measured by carotid intima-media thickness among African adults: a cross-sectional study

BACKGROUND

Increased waist circumference (WC) is one of the cardiovascular disease (CVD) risk factors used to predict cardiovascular events. Waist circumference cut-off values for predicting metabolic syndrome and other cardiovascular risks have been previously studied. Carotid intima-media thickness (CIMT) is one of the cardiovascular risk factor recently described and reported to be suitable as it is a direct measurement of vascular quality. Hence the aim of the present study was to determine the optimal WC cut-off point for the prediction of subclinical CVD.

METHODS

The study was a cross-sectional study using quantitative methods, conducted among 1318 adults aged between 40 and 60 years old, residing in a rural Black population in Limpopo province. Carotid Intima-Media Thickness measurements were performed using a LOGIQ ultrasound system (GE Healthcare, CT, USA). Waist Circumference (WC) (cm) was measured to the nearest 0.1 cm. Bivariate correlation, logistic regression and receiver operating characteristic were analysed using the statistical package for social sciences version 26.0 software.

RESULTS

Among the total population, 69% were women and 31% men with a mean age of 53 ± 7 years. Among women, WC at a cut-off value of 95 cm gave the highest sensitivity of 57%, the specificity of 55% and an area under the curve (AUC) of 0.588. In men, an optimum WC cut-off point of 82 cm yielded the highest sensitivity and specificity at 72% and 70% respectively, with an AUC of 0.767 p < 0.001.

CONCLUSION

The traditional waist circumference cut-off points (94 cm for women and 80 cm for men) that are currently used for the diagnosis of metabolic syndrome might not be suitable in the prediction of an increased CIMT.

Magnitude, components and predictors of metabolic syndrome in Northern Ethiopia: Evidences from regional NCDs STEPS survey, 2016

Background

Individuals with metabolic syndrome are five times more susceptible to chronic diseases. Assessment of its magnitude, components, and risk factors is essentials to deploy visible interventions needed to avoid further complications. The study aimed to assess magnitude, components, and predictors of metabolic syndrome in Tigray region northern Ethiopia, 2016.

Methods

Data were reviewed from Tigray region NCDs STEPs survey data base between May to June 2016. A total of 1476 adults aged 18–64 years were enrolled for the study. Multi-variable regression analysis was performed to estimate the net effect of size to risk factors associated with metabolic syndrome. Statistical significance was declared at p-value of ≤0.05 at 95% confidence interval (CI) for an adjusted odds ratio (AOR).

Results

The study revealed that unadjusted and adjusted prevalence rate of Metabolic Syndrome (MetS) were (CPR = 33.79%; 95%CI: 31.29%–36.36%) and (APR = 34.2%; 95% CI: 30.31%–38.06%) respectively. The most prevalent MetS component was low HDL concentration (CPR = 70.91%; 95%CI: 68.47%–73.27%) and (APR = 70.61; 95%CI; 67.17–74.05). While; high fasting blood glucose (CPR = 20.01% (95%CI: 18.03–22.12) and (APR = 21.72; 95%CI; 18.41–25.03) was the least ones. Eating vegetables four days a week, (AOR = 3.69, 95%CI; 1.33–10.22), a salt sauce added in the food some times (AOR = 5.06, 95%CI; 2.07–12.34), overweight (AOR = 24.28, 95%CI; 10.08–58.47] and obesity (AOR = 38.81; 12.20–111.04) had strong association with MetS.

Conclusion

The magnitude of metabolic syndrome was found to be close to the national estimate. Community awareness on life style modification based on identified MetS components and risk factors is needed to avoid further complications.

Prevalence of Type 2 Diabetes in South Africa: A Systematic Review and Meta-Analysis

Synthesis of existing prevalence data using rigorous systematic review methods is considered an effective strategy to generate representative and robust prevalence figures to inform health planning and policy. The purpose of this systematic review was to identify, collate, and synthesise all studies reporting the prevalence of total and newly diagnosed type 2 diabetes (T2DM), impaired glucose tolerance (IGT), and impaired fasting glucose (IFG) in South Africa. Four databases, PubMed, Scopus, Web of Science, and African Index Medicus were searched for articles published between January 1997 and June 2020. A total of 1886 articles were identified, of which 11 were included in the meta-analysis. The pooled prevalence in individuals 25 years and older was 15.25% (11.07–19.95%) for T2DM, 9.59% (5.82–14.17%) for IGT, 3.55% (0.38–9.61%) for IFG, and 8.29% (4.97–12.34%) for newly diagnosed T2DM. Although our pooled estimate may be imprecise due to significant heterogeneity across studies with regard to population group, age, gender, setting, diagnostic test, and study design, we provide evidence that the burden of glucose intolerance in South Africa is high. These factors contribute to the paucity of representative T2DM prevalence data. There is a need for well-designed epidemiological studies that use best-practice and standardised methods to assess prevalence.

Sarcopenic Obesity in Africa: A Call for Diagnostic Methods and Appropriate Interventions

This perspective aims to highlight the lack of current knowledge on sarcopenic obesity in Africa and to call for diagnostic methods and appropriate interventions. Sarcopenic obesity has been defined as obesity that occurs in combination with low muscle mass and function, which is typically evident in older adults. However, there has been no clear consensus on population-specific diagnostic criterion, which includes both gold-standard measures that can be used in a more advanced health care system, and surrogate measures that can be used in low-income settings with limited resources and funding. Importantly, low and middle-income countries (LMICs) across Africa are in an ongoing state of economic and social transition, which has contributed to an increase in the aging population, alongside the added burden of poverty, obesity, and associated co-morbidities. It is anticipated that alongside the increased prevalence of obesity, these countries will further experience an increase in age-related musculoskeletal diseases such as sarcopenia. The developmental origins of health and disease (DOHaD) approach will allow clinicians and researchers to consider developmental trajectories, and the influence of the environment, for targeting high-risk individuals and communities for treatment and/or prevention-based interventions that are implemented throughout all stages of the life course. Once a valid and reliable diagnostic criterion is developed, we can firstly assess the prevalence and burden of sarcopenic obesity in LMICs in Africa, and secondly, develop appropriate and sustainable interventions that target improved dietary and physical activity behaviors throughout the life course.

Association between food insecurity and key metabolic risk factors for diet-sensitive non-communicable diseases in sub-Saharan Africa: a systematic review and meta-analysis

In previous studies, food insecurity has been hypothesised to promote the prevalence of metabolic risk factors on the causal pathway to diet-sensitive non-communicable diseases (NCDs). This systematic review and meta-analysis aimed to determine the associations between food insecurity and key metabolic risk factors on the causal pathway to diet-sensitive NCDs and estimate the prevalence of key metabolic risk factors among the food-insecure patients in sub-Saharan Africa. This study was guided by the Centre for Reviews and Dissemination (CRD) guidelines for undertaking systematic reviews in healthcare. The following databases were searched for relevant literature: PubMed, EBSCOhost (CINAHL with full text, Health Source - Nursing, MedLine). Epidemiological studies published between January 2015 and June 2019, assessing the associations between food insecurity and metabolic risk outcomes in sub-Saharan African populations, were selected for inclusion. Meta-analysis was performed with DerSimonian-Laird's random-effect model at 95% confidence intervals (CIs). The I² statistics reported the degree of heterogeneity between studies. Publication bias was assessed by visual inspection of the funnel plots for asymmetry, and sensitivity analyses were performed to assess the meta-analysis results' stability. The Mixed Methods Appraisal Tool (MMAT) - Version 2018 was used to appraise included studies critically. The initial searches yielded 11,803 articles, 22 cross-sectional studies were eligible for inclusion, presenting data from 26,609 (46.8% males) food-insecure participants, with 11,545 (42.1% males) reported prevalence of metabolic risk factors. Of the 22 included studies, we identified strong evidence of an adverse association between food insecurity and key metabolic risk factors for diet-sensitive NCDs, based on 20 studies. The meta-analysis showed a significantly high pooled prevalence estimate of key metabolic risk factors among food-insecure participants at 41.8% (95% CI: 33.2% to 50.8%, I² = 99.5% p-value < 0.00) derived from 14 studies. The most prevalent type of metabolic risk factors was dyslipidaemia 27.6% (95% CI: 6.5% to 54.9%), hypertension 24.7% (95% CI: 15.6% to 35.1%), and overweight 15.8% (95% CI: 10.6% to 21.7%). Notably, the prevalence estimates of these metabolic risk factors were considerably more frequent in females than males. In this systematic review and meta-analysis, exposure to food insecurity was adversely associated with a wide spectrum of key metabolic risk factors, such as obesity, dyslipidaemia, hypertension, underweight, and overweight. These findings highlight the need to address food insecurity as an integral part of diet-sensitive NCDs prevention programmes. Further, these findings should guide recommendations on the initiation of food insecurity status screening and treatment in clinical settings as a basic, cost-effective tool in the practice of preventive medicine in sub-Saharan Africa.PROSPERO registration number: PROSPERO 2019 CRD42019136638.

Determination of optimal cut-off values for waist circumferences used for the diagnosis of the metabolic syndrome among Batswana adults (ELS 32)

BACKGROUND

To date, no definitive waist circumference (WC) cut-off values for abdominal obesity (AO) have been established for sub-Saharan Africa, including Botswana. Therefore, the classification of AO among these populations is based on European values. For accurate diagnosis of the metabolic syndrome (MetS), cut-off values reflective of the population investigated must be used.

OBJECTIVE

The study was an attempt to determine optimal cut-off values for AO among Batswana adults.

METHODS

The receiver operating characteristic curve was used to determine the optimal cut-off values for predicting at least two other risk factors of the MetS. Data were used from a descriptive cross-sectional study employing a complex multi-stage cluster sampling. Demographic and anthropometric measurements (weight and height, waist and hip circumferences), blood pressure, and blood glucose, triglycerides, high-density lipoprotein cholesterol and total cholesterol levels were collected from 384 men and 416 women in Gaborone and the surrounding villages.

RESULTS

The ability of waist circumference to predict at least two other risk factors of the MetS gave cut-off values of ≥ 91.0 cm (sensitivity 69.1% and specificity of 90.8%, area under the curve 0.85) for men and ≥ 82.3 cm (sensitivity of 88.6% and specificity of 58.9%, area under the curve of 0.76) for women.

CONCLUSIONS

There is a difference between the cut-off values for Europeans with those determined for Batswana adults. Inconsistencies in cut-off values used have the potential for undesirable consequences for cardiovascular risk stratification and prioritisation of preventative strategies for AO and the MetS. The need to determine population-, ethnic- and gender-based cut-off values for AO for Batswana adults has never been more paramount.

HIV infection, and overweight and hypertension: a cross-sectional study of HIV-infected adults in Western Kenya

Background

Non-communicable diseases (NCDs) are increasing in Kenya, where HIV/AIDS remains a leading cause of death; however, few studies have investigated obesity and hypertension among adults with HIV infection. We conducted a cross-sectional study in Homa Bay, Western Kenya, during 2015 to determine the prevalence of overweight/obesity and hypertension among HIV-infected adults and to identify their risk factors.

Results

Anthropometric measurements and a structured questionnaire were administered to adults with HIV infection receiving care at Mbita Sub-county Hospital. A total of 251 HIV-positive individuals were enrolled. More women were overweight (17.2%) and obese (3.6%) than underweight (8.3%). The prevalence of abdominal obesity was high in women (62.7%), especially those aged 30–39 years. The prevalence of hypertension was 9.8% and 11.8% in men and women, respectively. Male participants tended to develop hypertension at an early age. Multivariate analysis showed that female sex was significantly associated with abdominal obesity. Regarding clinical factors, we identified an association between overweight and a history of opportunistic infections, as well as between hypertension and World Health Organization clinical stage. Sixty percent of HIV-infected participants assumed that a very thin body size indicated HIV infection.

Conclusions

The main findings of this study include a greater prevalence of overweight than underweight as well as a high prevalence of abdominal obesity among women. Social perception toward body size among people with HIV infection might remain problematic. Individuals living with HIV in Kenya should receive preventive intervention for overweight and abdominal obesity, with consideration of relevant social and cultural aspects.

Waist-to-height ratio is a useful indicator of cardio-metabolic risk in South Africa

BACKGROUND

The use of waist-to-height ratio has been suggested as a better proxy indicator of central obesity.

OBJECTIVE

To compare the utility of waist-to-height ratio with commonly used adiposity indices of body mass index, waist circumference and waist-to-hip ratio to identify cardio-metabolic diseases in 25-74-year-old black residents of Cape Town.

METHODS

This cross-sectional study, stratified for age and gender, determined cardio-metabolic abnormalities by administered questionnaires, clinical measurements and biochemical analyses, including oral glucose tolerance tests. Correlations between adiposity indices with cardio-metabolic components were examined. Age- and gender-adjusted logistic regression analyses determined the associations of obesity by these adiposity indices with cardio-metabolic abnormalities.

RESULTS

The study comprised 392 men and 707 women. Compared with other adiposity indices, waist-to-height ratio in men correlated most closely with fasting (0.360) and 2-hour (0.388) glucose levels, total cholesterol (0.267), low-density lipoprotein cholesterol (0.351) and triglycerides (0.400). In women, waist-to-height ratio correlated the best with systolic blood pressure (0.254) and diastolic blood pressure (0.287). Of the adiposity indices, waist circumference was most strongly associated with diabetes (odds ratio 4.27, 95% confidence interval: 2.39-7.62), low high-density lipoprotein cholesterol (2.84, 1.90-4.26) and hypertriglyceridaemia (3.60, 2.03-6.40), whereas raised waist-to-height ratio was most closely related to hypertension (1.61, 1.07-2.42), hypercholesterolaemia (1.72, 1.04-2.83) and raised low-density lipoprotein cholesterol (2.46, 1.70-3.55).

CONCLUSIONS

Compared with other adiposity indices, the better correlation of waist-to-height ratio with many cardio-metabolic components, particularly in men, and the stronger association of raised waist-to-height ratio with hypertension, hypercholesterolaemia and raised low-density lipoprotein cholesterol support the utility of waist-to-height ratio in routine assessments of adiposity in this population, which may improve the identification of cardio-metabolic risk.

Anthropometric indices predicting incident hypertension in an Iranian population: The Isfahan cohort study

Objective:

The aim of the present study was to assess different obesity indices, as well as their best cut-off point, to predict the occurrence of hypertension (HTN) in an Iranian population.

Methods:

In a population-based study, subjects aged 35 years and older were followed for 7 years. Blood pressure was measured at baseline and after the follow-up. Anthropometry indices included body mass index (BMI), body adiposity index (BAI), the waist-to-height ratio (WHtR), the waist-to-hip ratio (WHpR), and waist and hip circumferences (WC and HC). Logistic regression was employed to calculate the odds ratio (OR) and 95% confidence intervals (CI) per standard deviation (SD) increment. The operating characteristic analysis was used to derive the best cut-off value for each index.

Results:

Among original 6504 participants, 2450 subjects who had no cardiovascular diseases (CVD) and HTN at baseline were revisited, and 542 (22.1%) new cases of HTN were detected. There were minimal differences between most indices in the adjusted models; however, the best HTN predictors were BMI (OR per SD 1.32; 95% CI 1.12–1.56) and almost equally WC (1.35; 1.13–1.60) in men and WC (1.20; 1.04–1.39) in women. As a binary predictor, BMI with a cut-off point of 24.9 kg/m² in men (1.91; 1.40–2.62) and WC with a cut-off point of 98 cm in women (1.57; 1.17–2.10) were the best in adjusted models. WC, WHpR, and WHtR were significantly associated with an increased risk of HTN only in participants whose weight was normal (BMI, 18.5–24.9 kg/m²).

Conclusion:

Therefore, BMI in men and WC in women were the best predictors of HTN, both as continuous and binary factors at their appropriate cut-off points.

Motives for physical activity in the adoption and maintenance of physical activity in middle-aged and old age outpatients with a mental disorder: A cross-sectional study from a low-income country

Within the trans-theoretical model (stages of change) and self-determination theory frameworks, we investigated motives for physical activity adoption and maintenance in middle-aged and old age people with a mental disorder from a low-income setting. Ninety Ugandan outpatients completed the Behavioral Regulation in Exercise Questionnaire-3 (BREQ-3) to assess exercise motives and the Patient-centred Assessment and Counselling for Exercise (PACE) to determine stage of change. The relationship between motives for physical activity and stage of change was investigated using MANOVA with post-hoc Scheffe tests. Higher amotivation levels were observed in the pre-action compared with action and maintenance stages, while except for external regulation, all regulation scores were significantly lower in the pre-action compared with action and maintenance stages. There were no significant differences in levels of motivational types between the action and maintenance stage. The study provides a platform for future research to investigate relationships between motivational factors and physical and mental health outcomes within physical activity interventions for middle-aged and old age people with a mental disorder.

Alterations in the metabolism of phospholipids, bile acids and branched-chain amino acids predicts development of type 2 diabetes in black South African women: a prospective cohort study

BACKGROUND

South Africa (SA) has the highest global projected increase in diabetes risk. Factors typically associated with insulin resistance and type 2 diabetes risk in Caucasians are not significant correlates in black African populations. Therefore, we aimed to identify circulating metabolite patterns that predict type 2 diabetes development in this high-risk, yet understudied SA population.

METHODS

We conducted a prospective cohort study in black SA women with normal glucose tolerance (NGT). Participants were followed for 13 years and developed (i) type 2 diabetes (n = 20, NGT-T2D), (ii) impaired glucose tolerance (IGT) (n = 27, NGT-IGT), or (iii) remained NGT (n = 28, NGT-NGT). Mass-spectrometry based metabolomics and multivariate analyses were used to elucidate metabolite patterns at baseline and at follow-up that were associated with type 2 diabetes development.

RESULTS

Metabolites of phospholipid, bile acid and branched-chain amino acid (BCAA) metabolism, differed significantly between the NGT-T2D and NGT-NGT groups. At baseline: the NGT-T2D group had i) a higher lysophosphatidylcholine:lysophosphatidylethanolamine ratio containing linoleic acid (LPC(C18:2):LPE(C18:2)), ii) lower proliferation-related bile acids (ursodeoxycholic- and chenodeoxycholic acid), iii) higher levels of leucine and its catabolic intermediates (ketoleucine and C5-carnitine), compared to the NGT-NGT group. At follow-up: the NGT-T2D group had i) lower LPC(C18:2) levels, ii) higher apoptosis-related bile acids (deoxycholic- and glycodeoxycholic acid), and iii) higher levels of all BCAAs and their catabolic intermediates.

CONCLUSIONS

Changes in lysophospholipid metabolism and the bile acid pool occur during the development of type 2 diabetes in black South African women. Further, impaired leucine catabolism precedes valine and isoleucine catabolism in the development of type 2 diabetes. These metabolite patterns can be useful to identify and monitor type 2 diabetes risk >10 years prior to disease onset and provide insight into the pathophysiology of type 2 diabetes in this high risk, but under-studied population.

Adiposity Mediates the Association between the Dietary Inflammatory Index and Markers of Type 2 Diabetes Risk in Middle-Aged Black South African Women

The dietary inflammatory index (DII®), a validated tool used to measure the inflammatory potential of the diet, has been associated with metabolic disorders in various settings, but not in African populations. The aim of this study was to investigate whether the DII is associated with markers of type 2 diabetes (T2D) risk, and if this association is mediated by adiposity and/or low-grade inflammation, in black South Africa women. Energy-adjusted-DII (E-DII) scores were calculated in 190 women (median age, 53 years) from the Birth-to-Twenty plus cohort using a validated food frequency questionnaire. Fasting glucose, insulin, HbA1c, and inflammatory cytokines were measured, and an oral glucose tolerance test performed. Basic anthropometry and dual-energy x-ray absorptiometry-derived body fat, including estimate of visceral adipose tissue (VAT) area, were measured. E-DII scores were associated with all markers of T2D risk, namely, fasting glucose and insulin, HbA1c, HOMA2-IR, two-hour glucose and Matsuda index (all p < 0.05). After adjusting for age, measures of adiposity, but not inflammatory cytokines, mediated the association between E-DII and markers of T2D risk (p < 0.05). Measures of central obesity had proportionally higher (range: 23.5-100%) mediation effects than total obesity (range: 10-60%). The E-DII is associated with T2D risk through obesity, in particular central obesity, among black middle-aged South African women.

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

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.

Anthropometric parameter that best predict metabolic syndrome in South west Nigeria

AIM

This study compared the ability of anthropometric parameters to predict Metabolic Syndrome (MetS).

METHODS

Eleven anthropometric parameters: waist circumference (WC), body mass index (BMI), waist-to-height ratio (WHtR), a body shape index (ABSI), body roundness index (BRI), visceral adiposity index (VAI), abdominal volume index (AVI), Conicity Index (CI), body adiposity index (BAI), lipid accumulation product (LAP) and waist circumference-triglyceride index (WTI) were measured and calculated in apparently healthy subjects with and without MetS. A receiver operating characteristic (ROC) curve was applied to assess their ability to predict MetS.

RESULTS

Of the 535 subjects recruited 23% had MetS. WC had the largest area under the curve (AUC) in both men (0.814 95% CI 0.721-0.907) and women (0.819 95%CI 0.771-0.867). This did not differ from the AUC of BMI, WHtR, BRI, CI, BAI, LAP in men and BMI, WHtR, BAI, LAP, VAI and WTI in women (P > 0.05). The cutoff point for WC was 89.5 cm and 91.8 cm in men and women respectively. The AUC of WC was the largest in the 40-49 and 60 years and above age groups while the AUC of LAP was the largest for age groups 30-39 and 50-59 years.

CONCLUSION

Of the 11 anthropometric parameters assessed, the WC was the best at predicting MetS in both men and women. There is need to ascertain the cutoff point and establish landmark for measuring WC especially for the sub Saharan region.

Do current guidelines for waist circumference apply to black Africans? Prediction of insulin resistance by waist circumference among Africans living in America

Background

To lower the risk of diabetes and heart disease in Africa, identification of African-centred thresholds for inexpensive biomarkers of insulin resistance (IR) is essential. The waist circumference (WC) thresholds that predicts IR in African men and women have not been established, but investigations recently conducted in Africa using indirect measures of IR suggest IR is predicted by WC of 80–95 cm in men and 90–99 cm in women. These WC cannot be used for guidelines until validated by direct measurements of IR and visceral adipose tissue (VAT). Therefore, we determined in a group of African-born black people living in America (A) the WC, which predicts IR and (B) the influence of abdominal fat distribution on IR.

Methods

The 375 participants (age 38±10  years (mean±SD), 67% men) had IR determined by HOMA-IR and Matsuda index. VAT and subcutaneous adipose tissue (SAT) were measured by abdominal CT scans. Optimal WC for the prediction of IR was determined in sex-specific analyses by area under the receiver operating characteristic (AUC-ROC) and Youden index.

Results

Women had more SAT (203±114 vs 128±74  cm²) and less VAT than men (63±48 vs 117±72  cm², p<0.001). Optimal WC for prediction of IR in men and women were: 91 cm (AUC-ROC: 0.80±0.03 (mean±SE)) and 96 cm (AUC-ROC: 0.81±0.08), respectively. Regression analyses revealed a significant sex–VAT interaction (p<0.001). Therefore, for every unit increase in VAT, women had a 0.94 higher unit increase in SAT and 0.07 higher unit increase in WC than men.

Conclusion

Working with a group of African-born black people living in America, we accessed technology, which validated observations made in Africa. Higher SAT at every level of VAT explained why the WC that predicted IR was higher in women (96 cm) than men (91 cm). For Africans to benefit from WC measurements, convening a panel of experts to develop evidence-based African-centred WC guidelines may be the way forward.

Addressing the problem of obesity and associated cardiometabolic risk in black South African women - time for action!

The PhD thesis of Gradidge, entitled ‘Factors associated with obesity and metabolic syndrome in an ageing cohort of black women living in Soweto, Johannesburg (Study of Women in and Entering Endocrine Transition [SWEET])’, attempts to understand the determinants of obesity and metabolic syndrome (MetS) in a population of urban-dwelling black South African women. A conceptual framework is presented, which positions obesity as the central risk factor for MetS, and includes the possible influence of socioeconomic status, lifestyle behaviours and body size perceptions, as key determinants of obesity. This commentary focuses on the two main findings of Gradidge’s thesis, namely, (i) physical activity and sedentary behaviour, and (ii) body composition and adiponectin, as risk factors for obesity and MetS in black South African women. Despite a high prevalence of obesity (48%), Gradidge showed that 75% of the women taking part in the study were meeting WHO guidelines on physical activity. This commentary suggests that the relationship between physical activity and cardiometabolic risk may be confounded by socioeconomic status. Alternatively, the intensity, and not necessarily the volume, of activity, as well as high rates of sedentary behaviour are posited as important determinants of obesity and MetS in black South African women. Accordingly, this commentary questions the veracity of the WHO guidelines on physical activity in developing countries, where most women meet the guidelines but have very poor cardiorespiratory fitness, are obese and are at high risk of MetS. Gradidge also showed that the most consistent and significant correlate of MetS in this cohort of middle-aged women was low serum levels of adiponectin. This commentary highlights various lifestyle interventions that have been shown to increase adiponectin levels. Finally, the importance of immediate action to address the problem of obesity and MetS is emphasised.

Genetic variants in SEC16B are associated with body composition in black South Africans

Objective

The latest genome-wide association studies of obesity-related traits have identified several genetic loci contributing to body composition (BC). These findings have not been robustly replicated in African populations, therefore, this study aimed to assess whether European BC-associated gene loci played a similar role in a South African black population.

Methods

A replication and fine-mapping study was performed in participants from the Birth to Twenty cohort (N = 1,926) using the Metabochip. Measurements included body mass index (BMI), waist and hip circumference, waist-to-hip ratio (WHR), total fat mass, total lean mass and percentage fat mass (PFM).

Results

SNPs in several gene loci, including SEC16B (P_adj <  9.48 × 10⁻⁷), NEGR1 (P_adj < 1.64 × 10⁻⁶), FTO (P_adj < 2.91 × 10⁻⁵), TMEM18 (P_adj < 2.27 × 10⁻⁵), and WARS2(P_adj < 3.25 × 10⁻⁵) were similarly associated (albeit not at array-wide signficance (P ≤ 6.7 × 10⁻⁷) with various phenotypes including fat mass, PFM, WHR linked to BC in this African cohort, however the associations were driven by different sentinel SNPs. More importantly, DXA-derived BC measures revealed stronger genetic associations than simple anthropometric measures. Association signals generated in this study were shared by European and African populations, as well as unique to this African cohort. Moreover, sophisticated estimates like DXA measures enabled an enhanced characterisation of genetic associations for BC traits.

Conclusion

Results from this study suggest that in-depth genomic studies in larger African cohorts may reveal novel SNPs for body composition and adiposity, which will provide greater insight into the aetiology of obesity.

"I just wish that everything is in one place": facilitators and barriers to continuity of care among HIV-positive, postpartum women with a non-communicable disease in South Africa

HIV and non-communicable diseases (NCD) are co-epidemics in South Africa. Comorbid individuals must engage in lifelong care. Postpartum HIV-positive women in South Africa are at high risk of dropping out of HIV care. We explored healthcare utilization among postpartum women requiring chronic management of HIV and NCD. From August - December 2016, we enrolled 25 women in Soweto, South Africa, and conducted one-time interviews. All participants were adult (≥18 years), HIV-positive, postpartum, and diagnosed with a NCD that required further evaluation after delivery. We developed a conceptual model that describes how maternal factors, interaction with environments, and social networks influence follow up engagement. Barriers to follow-up included separate visit days, increased time commitment, transportation and logistics, unfamiliar clinic environments, and disrespectful staff. Factors facilitating patient engagement included social support and partner disclosure. Women were more likely to turn to friends and family for advice regarding HIV or the NCD, rather than a clinic. Women prioritized infant care after delivery, suggesting that baby care may be an entry point for improving maternal care after delivery. Our results support advocating for better integration of services at the primary care level as a method to improve continuity of care for both women and children.

Influence of socioeconomic status on changes in body size and physical activity in ageing black South African women

Background

The increasing prevalence of obesity in sub-Saharan African women is not well understood, and black South African women in the region are particularly vulnerable. This study aimed to examine whether the relationship of socioeconomic status (SES) with changes in body mass index (BMI) and waist circumference (WC) is mediated by physical activity in ageing African women.

Methods

In a longitudinal analysis of the 518 caregivers associated with the Birth to Twenty Plus study, the role of SES associated with 10-year changes in BMI and WC was tested using structural equation modelling (SEM). The degree of mediation of moderate-vigorous physical activity (MVPA) and sitting time in this association was also assessed.

Results

The prevalence of obesity increased significantly from baseline to follow-up (p < 0.0001). In the SEM models, baseline SES had a direct positive effect on changes in BMI (β, 95% CI, 0.02 (0.005 to 0.04), and a direct negative effect on changes in MVPA (β, 95% CI, - 3.81 (- 6.92 to - 0.70). Baseline MVPA had a direct negative effect (β, 95% CI, - 0.002 (- 0.003 to - 0.0003) and indirect positive effect via change in MVPA (β, 95% CI, 0.01 (0.0001 to 0.001) on change in WC.

Conclusions

Our study demonstrates the role and interaction of sociodemographic and behavioural predictors of obesity, and suggests a multifaceted approach to management of the crisis in communities of ageing urban African women.

Exercise self-efficacy correlates in people with psychosis

Despite the recognition of the importance of exercise self-efficacy in exercise adoption and maintenance, previous investigations on exercise self-efficacy in people with psychosis is scarce. The present study aimed to (1) explore if exercise self-efficacy differed between stages of behavior change in Ugandan outpatients with psychosis, and (2) assess sociodemographic, clinical and motivational correlates of exercise self-efficacy. In total, 48 patients (24 women) completed the Exercise Self-Efficacy Scale (ESES), the Patient-centered Assessment and Counseling for Exercise questionnaire, the Brief Symptoms Inventory-18 (BSI-18), and questions pertaining to intrinsic motivation in the Behavioral Regulation in Exercise Questionnaire-2. Additionally, participants were asked about their exercise behavior in the past 7 days and screened for cardio-metabolic risk factors. Higher ESES-scores were observed in those in the maintenance (n = 17) versus those in the pre-action stage (n = 17) of behavior change. Higher ESES-scores were also significantly associated with lower BSI-18 somatization and higher intrinsic motivation scores. Our data indicated that health care professionals should assist patients with psychosis in interpreting physiological states during exercise. Future research should explore whether bolstering such sources of information might directly or indirectly effect exercise self-efficacy.

Motives for physical activity in the adoption and maintenance of physical activity in men with alcohol use disorders

Within the self-determination theory and the trans-theoretical model (stages of change) frameworks, we investigated motives for physical activity adoption and maintenance in men with alcohol use disorder (AUD). Fifty Ugandan patients completed the Behavioral Regulation in Exercise Questionnaire-3 (BREQ-3) to assess exercise motives, the Patient-centred Assessment and Counselling for Exercise (PACE) to determine stage of change and the Alcohol Use Disorders Identification Test. The relationship between motives for physical activity and stage of change was investigated using ANOVA with post-hoc Scheffe tests. Multivariate analyses found significantly higher levels of introjected, identified and integrated motivation in the action and maintenance stage versus the pre-action stage. There were no differences in intrinsic motivation between the stages of change. Our results suggest that in order to adopt and maintain an active lifestyle the most important source of motivation comes from the benefits that may be obtained rather than from the inherent pleasure or challenge associated with it. The study provides a platform for future research to investigate the importance of autonomous motivation within physical activity interventions for people with AUD.

Adherence to physical activity recommendations and physical and mental health risk in people with severe mental illness in Uganda

This study investigated cardio-metabolic risk factors among patients with severe mental illness who do or do not meet the recommendations of 150min per week of physical activity. A secondary aim was to assess whether those that do meet the recommendations report lower levels of mental health symptoms. 107 (60♀) Ugandan in- and outpatients (mean age=34.4 ± 9.7 years) with severe mental illness (depression=7, bipolar disorder=55, schizophrenia=45) completed the Physical Activity Vital Sign (PAVS) method and Brief Symptoms Inventory -18. Participants were also screened for abdominal obesity (waist circumference>90cm), overweight (body mass index≥25) and hypertension (systolic pressure≥140mmHg and/or diastolic pressure≥90mmHg).48.6% (n = 52) of patients met the physical activity recommendations as assessed by the PAVS method. 41.1% (n = 44) were overweight, 40.2% (n = 43) had abdominal obesity and 23.4% (n = 25) had hypertension. Those who did not meet the physical activity recommendations were significantly older, had a higher BSI-18 somatisation score, and had a higher risk of overweight [relative risk (RR) = 2.88, 95% confidence interval (CI) = 1.59-4.99], abdominal obesity (RR = 1.82, 95%CI = 1.13-2.93), and hypertension (RR = 2.16, 95%CI = 0.99-4.73). The PAVS is a feasible method of assessing physical activity among patients with severe mental illness in a low resource setting. The PAVS may have clinical utility for physical and mental health risk stratification.

Optimal waist circumference cut-off points for predicting metabolic syndrome among low-income black South African adults

OBJECTIVE

Waist circumference has been identified as one of the strongest predictive tool for metabolic syndrome. This study determines the optimal cut-off point of waist circumference for metabolic syndrome among low-income earning South African black population, in Eastern Cape, South Africa. The optimal waist circumference cut-off point was determined through receiver operating characteristics analysis using the maximum Youden index.

RESULTS

Among men, waist circumference at a cut-off value of 95.25 cm yielded the highest Youden index of 0.773 (sensitivity = 98%, specificity = 79%, area under curve 0.893). For women, waist circumference of 89.45 cm yielded the highest Youden index of 0.339 (sensitivity = 88%, specificity = 46%, area under curve 0.713). The prevalence of metabolic syndrome among men, women and both sexes using the new cut-off points were: 17.8, 20.8 and 17.7%, respectively, compared to; 15.6, 24.8 and 21.8%, using the traditional cut-off values of 94 and 80 cm for men and women, respectively. The traditional waist circumference value slightly under-estimated the prevalence of metabolic syndrome among men and over-estimated among women and the overall population. A specific waist circumference cut-off point for South African blacks is needed for correct identification of the metabolic state of the populace in order to develop appropriate interventions.

Deriving an optimal threshold of waist circumference for detecting cardiometabolic risk in sub-Saharan Africa

BACKGROUND

Waist circumference (WC) thresholds derived from western populations continue to be used in sub-Saharan Africa (SSA) despite increasing evidence of ethnic variation in the association between adiposity and cardiometabolic disease and availability of data from African populations. We aimed to derive a SSA-specific optimal WC cut-point for identifying individuals at increased cardiometabolic risk.

METHODS

We used individual level cross-sectional data on 24 181 participants aged ⩾15 years from 17 studies conducted between 1990 and 2014 in eight countries in SSA. Receiver operating characteristic curves were used to derive optimal WC cut-points for detecting the presence of at least two components of metabolic syndrome (MS), excluding WC.

RESULTS

The optimal WC cut-point was 81.2 cm (95% CI 78.5-83.8 cm) and 81.0 cm (95% CI 79.2-82.8 cm) for men and women, respectively, with comparable accuracy in men and women. Sensitivity was higher in women (64%, 95% CI 63-65) than in men (53%, 95% CI 51-55), and increased with the prevalence of obesity. Having WC above the derived cut-point was associated with a twofold probability of having at least two components of MS (age-adjusted odds ratio 2.6, 95% CI 2.4-2.9, for men and 2.2, 95% CI 2.0-2.3, for women).

CONCLUSION

The optimal WC cut-point for identifying men at increased cardiometabolic risk is lower (⩾81.2 cm) than current guidelines (⩾94.0 cm) recommend, and similar to that in women in SSA. Prospective studies are needed to confirm these cut-points based on cardiometabolic outcomes.International Journal of Obesity advance online publication, 31 October 2017; doi:10.1038/ijo.2017.240.

Optimal waist circumference threshold for diagnosing metabolic syndrome in African people living with HIV infection

Background

The applicability of the internationally advocated cut-off points of waist circumference (WC) derived from Caucasians to diagnose metabolic syndrome (MS) in HIV-infected Africans is unknown. This study aimed to determine the optimal WC cutoffs for MS diagnosis in HIV-infected people receiving care at public healthcare facilities in the Western Cape Province in South Africa.

Methods

Data from 748 randomly selected participants (591 women), with a median age of 38 years, were analysed. The Youden’s index and the top-left-point approaches were used to determine the optimal cutoffs of WC for predicting ≥2 non-adipose MS components.

Results

The two approaches generated the same WC cut-off point in women, 92 cm (sensitivity 64%, specificity 64%) but different cut-off points in men: 87 cm (sensitivity 48%, specificity 85%) based on the Younden’s index and 83 cm (sensitivity 59%, specificity 74%) by the top-left-point method. The advocated thresholds of 94 cm in men had low sensitivity (30%) but high specificity (92%) whereas 80 cm in women showed low specificity (32%) but high sensitivity (85%) for diagnosing MS in this sample. Most African-specific cut-off points performed well, with 90 cm providing acceptable performance in both men (sensitivity 43%, specificity 88%) and women (sensitivity 66%, specificity 59%).

Conclusions

This study underlines the sub-optimal performance of internationally recommended WC thresholds for MS diagnosis in HIV-infected Africans, and supports the need to revisit the guidelines on WC criterion in African population across the board. A single threshold of 90 cm for both genders would be a practical suggestion.

Breast conservation surgery versus total mastectomy among women with localized breast cancer in Soweto, South Africa

PURPOSE

Breast conserving surgery (BCS) has become the preferred surgical option for the management of patients with nonmetastatic breast cancer in high-income countries. However, little is known about the distribution and determinants of BCS in low-and middle-income countries, especially those with high HIV prevalence.

METHODS

We compared demographic and clinical characteristics of female patients who received BCS and those who received total mastectomy (TM) for nonmetastatic invasive carcinoma of the breast in Soweto, South Africa, 2009-2011. We also developed a multivariable logistic regression model of predictors of type of surgery.

RESULTS

Of 445 patients, 354 (80%) underwent TM and 91 (20%) BCS. Of 373 patients screened for HIV, 59 (15.8%) tested positive. Eighty-two of 294 patients with stage I/II disease (28%), but just 9 of 151 (6%) with stage III disease had BCS (p<0.001). All women who received BCS (except for seven who received completion mastectomy within 6 weeks of BCS) and 235 (66.4%) women who received TM were referred for radiation therapy (RT). In our multivariable analysis, age group 50-59 years (OR = 2.28, 95% CI = 1.1-4.8) and ≥70 years (OR = 9.55, 95% CI = 2.9-31.2) vs. age group <40 years, stage at diagnosis (stage II (OR = 3.79, 95% CI = 1.6-8.2) and stage III (OR = 27.8, 95% CI = 9.0-78.8) vs. stage 1, HIV (HIV positive (OR = 3.19, 95% CI = 1.3-7.9) vs. HIV negative) and HER2-enriched subtype (OR = 3.50, 95% CI = 1.2-10.1) vs. triple negative were independently associated with TM.

CONCLUSION

TM was more common than BCS among patients with nonmetastatic breast cancer in Soweto, not only among patients with locally advanced disease at diagnosis, but also among women with stage I and II disease.

Metabolic syndrome and its predictors in an urban population in Kenya: A cross sectional study

BACKGROUND

The metabolic syndrome (MetS) is a clustering of interrelated risk factors which doubles the risk of cardio-vascular disease (CVD) in 5-10 years and increases the risk of type 2 diabetes 5 fold. The identification of modifiable CVD risk factors and predictors of MetS in an otherwise healthy population is necessary in order to identify individuals who may benefit from early interventions. We sought to determine the prevalence of MetS as defined by the harmonized criteria and its predictors in subjectively healthy black Africans from various urban centres in Kenya.

METHOD

We used data collected from healthy black Africans in Kenya as part of a global study on establishing reference intervals for common laboratory tests. We determined the prevalence of MetS and its components using the 2009 harmonized criterion. Receiver operator characteristic (ROC) curve analysis was used to determine the area under the curves (AUC) for various predictors of MetS. Youden index was used to determine optimum cut-offs for quantitative measurements such as waist circumference (WC).

RESULTS

A total of 528 participants were included in the analysis. The prevalence of MetS was 25.6% (95% CI: 22.0%-29.5%). Among the surrogate markers of visceral adiposity, lipid accumulation product was the best predictor of MetS with an AUC of 0.880 while triglyceride was the best predictor among the lipid parameters with an AUC of 0.816 for all participants. The optimal WC cut-off for diagnosing MetS was 94 cm and 86 cm respectively for males and females.

CONCLUSIONS

The prevalence of MetS was high for a healthy population highlighting the fact that one can be physically healthy but have metabolic derangements indicative of an increased CVD risk. This is likely to result in an increase in the cases of CVD and type 2 diabetes in Kenya if interventions are not put in place to reverse this trend. We have also demonstrated the inappropriateness of the WC cut-off of 80 cm for black African women in Kenya when defining MetS and recommend adoption of 86 cm.

Metabolic Syndrome After HIV Acquisition in South African Women

BACKGROUND

Noncommunicable diseases are common among chronically infected patients with HIV in the developed world, but little is known about these conditions in African cohorts. We assessed the epidemiology of metabolic syndrome among young South African women during the first 3 years after HIV acquisition.

METHODS

A total of 160 women were followed prospectively in the CAPRISA 002 Acute Infection study. Metabolic syndrome was defined as a constellation of hyperlipidemia, hypertension, hyperglycemia/diabetes, and abdominal obesity. Time trends were assessed using generalized estimation equation models.

RESULTS

Median age was 24 years and body mass index 27 kg/m. Prevalence of metabolic syndrome at infection was 8.7% increasing to 19.2% over 36 months (P = 0.001). The proportion of women with body mass index >30 kg/m increased from 34.4% to 47.7% (P = 0.004), those with abnormal waist circumference and elevated blood pressure increased from 33.5% to 44.3% (P = 0.060) and 23.8% to 43.9% (P < 0.001), respectively. Incidence of metabolic syndrome was 9.13/100 person-years (95% CI: 6.02 to 13.28). Predictors of metabolic syndrome were age (per year increase odds ratio (OR) = 1.12; 95% CI: 1.07 to 1.16), time postinfection (per year OR = 1.47; 95% CI: 1.12 to 1.92), family history of diabetes (OR = 3.13; 95% CI: 1.71 to 5.72), and the human leukocyte antigen (HLA)-B*81:01 allele (OR = 2.95; 95% CI: 1.21 to 7.17), whereas any HLA-B*57 or B*58:01 alleles were protective (OR = 0.34; 95% CI: 0.15 to 0.77). HIV-1 RNA (OR = 0.89; 95% CI: 0.62 to 1.27) and CD4 count (OR = 1.03; 95% CI: 0.95 to 1.11) did not predict metabolic syndrome.

CONCLUSIONS

The high burden of metabolic conditions in young South African HIV-infected women highlights the need to integrate noncommunicable disease and HIV care programs. Interventions to prevent cardiovascular disease must start at HIV diagnosis, rather than later during the disease course.

Review: Metabolic Syndrome in Black South African Women

The prevalence of metabolic syndrome is increasing in African populations, and is particularly high in Black South African women (42%) vs women in the United Kingdom (23%) and the United States of America (36%). This population group is also known to have the highest prevalence of obesity in the sub-Saharan African region (42%), and consequently, a high risk of non-communicable diseases. In this article, we discuss factors (abdominal subcutaneous fat, visceral fat, lean mass, adiponectin, leptin, vitamin D, smoking and menopausal status) that have been investigated for their possible association with metabolic syndrome in African women, and discuss some recommendations for management of the syndrome. In particular, the infrastructural development of HIV/AIDS clinics in South Africa provides an ideal integrated platform to cater to the treatment needs of patients with multiple chronic morbidities.

Non-communicable disease syndemics: poverty, depression, and diabetes among low-income populations

The co-occurrence of health burdens in transitioning populations, particularly in specific socioeconomic and cultural contexts, calls for conceptual frameworks to improve understanding of risk factors, so as to better design and implement prevention and intervention programmes to address comorbidities. The concept of a syndemic, developed by medical anthropologists, provides such a framework for preventing and treating comorbidities. The term syndemic refers to synergistic health problems that affect the health of a population within the context of persistent social and economic inequalities. Until now, syndemic theory has been applied to comorbid health problems in poor immigrant communities in high-income countries with limited translation, and in low-income or middle-income countries. In this Series paper, we examine the application of syndemic theory to comorbidities and multimorbidities in low-income and middle-income countries. We employ diabetes as an exemplar and discuss its comorbidity with HIV in Kenya, tuberculosis in India, and depression in South Africa. Using a model of syndemics that addresses transactional pathophysiology, socioeconomic conditions, health system structures, and cultural context, we illustrate the different syndemics across these countries and the potential benefit of syndemic care to patients. We conclude with recommendations for research and systems of care to address syndemics in low-income and middle-income country settings.

The Optimal Ethnic-Specific Waist-Circumference Cut-Off Points of Metabolic Syndrome among Low-Income Rural Uyghur Adults in Far Western China and Implications in Preventive Public Health

Background: Metabolic syndrome is pandemic; however, the cut-off values for waist circumference (WC) vary widely depending on the ethnic groups studied and the criteria applied for WC measurement. Previous studies for defining optimal WC cut-off points included high-income and urban settings, and did not cover low-income, rural settings, especially for ethnic minorities. This study aimed at defining optimal ethnic-specific WC cut-off points in a low-income, rural population comprising the largest inhabitant minority group residing in far Western China. Methods: Questionnaire-based surveys, physical examinations, and blood testing of 3542 individuals were conducted in 2010, using a stratified cluster random sampling method in rural Uyghur residents (≥18 years old) from 12 villages in Xinjiang, China, approximately 4407 km away from the capital city, Beijing. Metabolic syndrome was defined according to the International Diabetes Federation (IDF) criteria. Optimal, ethnic-specific WC cut-off values for diagnosing metabolic syndrome were determined using receiver operator characteristic (ROC) curve analysis. Results: As WC increased, there was a significant, increasing trend of detection and risk in rural Uyghur adults, regardless of the presence of ≥1 or ≥2 components of metabolic syndrome by IDF criteria. The optimal ethnic-specific WC cut-off point to predict the presence of metabolic syndrome was 85 cm for men and 82 cm for women. With these cut-off points, the prevalence rates of metabolic syndrome among men, women, and overall population in Uyghur adults were 19.5%, 23.0%, and 21.3%, respectively. Conclusions: We report a high prevalence of metabolic syndrome, especially in women, among rural Uyghurs in Western China. A WC cut-off of 85 cm in men and 82 cm in women was the best predictor of metabolic syndrome in this population. Because of the cost-effectiveness in measuring WC, we recommend that these WC cut-off points be integrated into local preventive policies for public health as the primary screening criteria for metabolic syndrome and related diseases among low-income, rural minorities.

Factors associated with obesity and metabolic syndrome in ageing black South African women

BACKGROUND

The incidence of obesity and related metabolic diseases is high and increasing in sub-Saharan African women. Evidence on the determinants of these diseases is limited, particularly in black South African women.

OBJECTIVE

This PhD review attempts to understand the determinants of obesity and metabolic syndrome (MetS) in a population of ageing urban-dwelling black South African women.

METHODS

Drawing on the longitudinal Birth-to-Twenty-Plus cohort, data were collected in 2002/03 and 2012/13, including information on behavioural factors (smoking, sitting time, physical activity, smokeless tobacco, and alcohol consumption), body-size perception, body composition (measures of adiposity and lean mass), blood pressure, and cardiometabolic biomarkers (lipid profile, fasting insulin, fasting blood glucose, insulin resistance, leptin, and adiponectin).

RESULTS

The prevalence of obesity and related cardiovascular disease risk was high and increased significantly over the 10 year period. Despite most of the study population being physically active, sitting time was high and associated with elevated blood pressure and hypertriglyceridaemia. Two groups of people were observed, those who were happy and those who were unhappy with their body size. In logistic regression analysis, the risk of MetS was lowered by abdominal subcutaneous adipose tissue and adiponectin, and increased by age, smoking, truncal lean mass, and insulin resistance.

CONCLUSIONS

Obesity was confirmed to be increasing in black South African women, despite most women being sufficiently active according to guidelines of ≥150 min activity/week. Nevertheless, the contribution of sitting time to poor health outcomes is evident in this study population and must be addressed, particularly in women who are content with being obese. The novel finding of the effects of abdominal subcutaneous tissue and truncal lean mass with MetS requires further investigation. The protective effect of adiponectin against MetS is an important finding which highlights the novel interaction between adiposity and cardiometabolic diseases in black South African women.

The need for an integrated approach for chronic disease research and care in Africa

With the changing distribution of infectious diseases, and an increase in the burden of non-communicable diseases, low- and middle-income countries, including those in Africa, will need to expand their health care capacities to effectively respond to these epidemiological transitions. The interrelated risk factors for chronic infectious and non-communicable diseases and the need for long-term disease management, argue for combined strategies to understand their underlying causes and to design strategies for effective prevention and long-term care. Through multidisciplinary research and implementation partnerships, we advocate an integrated approach for research and healthcare for chronic diseases in Africa.

H3Africa AWI-Gen Collaborative Centre: a resource to study the interplay between genomic and environmental risk factors for cardiometabolic diseases in four sub-Saharan African countries

Africa is experiencing a rapid increase in adult obesity and associated cardiometabolic diseases (CMDs). The H3Africa AWI-Gen Collaborative Centre was established to examine genomic and environmental factors that influence body composition, body fat distribution and CMD risk, with the aim to provide insights towards effective treatment and intervention strategies. It provides a research platform of over 10 500 participants, 40–60 years old, from Burkina Faso, Ghana, Kenya and South Africa. Following a process that involved community engagement, training of project staff and participant informed consent, participants were administered detailed questionnaires, anthropometric measurements were taken and biospecimens collected. This generated a wealth of demographic, health history, environmental, behavioural and biomarker data. The H3Africa SNP array will be used for genome-wide association studies. AWI-Gen is building capacity to perform large epidemiological, genomic and epigenomic studies across several African counties and strives to become a valuable resource for research collaborations in Africa.

Measurement of overweight and obesity an urban slum setting in sub-Saharan Africa: a comparison of four anthropometric indices

BACKGROUND

As a result of both genetic and environmental factors, the body composition and topography of African populations are presumed to be different from western populations. Accordingly, globally accepted anthropometric markers may perform differently in African populations. In the era of rapid emergence of cardio-vascular diseases in sub-Saharan Africa, evidence about the performance of these markers in African settings is essential. The aim of this study was to investigate the inter-relationships among the four main anthropometric indices in measuring overweight and obesity in an urban poor African setting.

METHODS

Data from a cardiovascular disease risk factor assessment study in urban slums of Nairobi were analyzed. In the major study, data were collected from 5190 study participants. We considered four anthropometric markers of overweight and obesity: Body Mass Index, Waist Circumference, Waist to Hip Ratio, and Waist to Height Ratio. Pairwise correlations and kappa statistics were used to assess the relationship and agreement among these markers, respectively. Discordances between the indices were also analyzed.

RESULTS

The weighted prevalence of above normal body composition was 21.6 % by body mass index, 28.9 % by waist circumference, 45.5 % by waist to hip ratio, and 38.9 % by waist to height ratio. The overall inter-index correlation was +0.44. Waist to hip ratio generally had lower correlation with the other anthropometric indices. High level of discordance exists between body mass index and waist to hip ratio. Combining the four indices shows that 791 (16.1 %) respondents had above normal body composition in all four indices. Waist circumference better predicted hypertension and hyperglycemia while waist to height ratio better predicted hypercholesterolemia.

CONCLUSIONS

There exists a moderate level of correlation and a remarkable level of discordance among the four anthropometric indices with regard to the ascertainment of abnormal body composition in an urban slum setting in Africa. Waist circumference is a better predictor of cardio-metabolic risk.

Metabolic and Body Composition Risk Factors Associated with Metabolic Syndrome in a Cohort of Women with a High Prevalence of Cardiometabolic Disease

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.

Maximum accuracy obesity indices for screening metabolic syndrome in Nigeria: A consolidated analysis of four cross-sectional studies

BACKGROUND

In sub-Saharan Africa, there is no precise use of metabolic syndrome (MetS) definitions and risk factors screening indices in many clinical and public health services. Methods proposed and used in Western populations are adopted without validation within the local settings. The aim of the study is to assess obesity indices and cut-off values that maximise screening of MetS and risk factors in the Nigerian population.

METHOD

A consolidated analysis of 2809 samples from four population-based cross-sectional study of apparently healthy persons≥18 years was carried out. Optimal waist circumference (WC) and waist-to-height ratio (WHtR) cut points for diagnosing MetS and risk factors were determined using Optimal Data Analysis (ODA) model. The stability of the predictions of the models was also assessed.

RESULTS

Overall mean values of BMI, WC and WHtR were 24.8±6.0kgm(-2), 84.0±11.3cm and 0.52±0.1 respectively. Optimal WC cut-off for discriminating MetS and diabetes was 83cm in females and 85cm in males, and 82cm in females and 89cm in males, respectively. WC was stable in discriminating diabetes than did WHtR and BMI, while WHtR showed better stability in predicting MetS than WC and BMI.

CONCLUSION

The study shows that the optimal WC that maximises classification accuracy of MetS differs from that currently used for sub-Saharan ethnicity. The proposed global WHtR of 0.50 may misclassify MetS, diabetes and hypertension. Finally, the WC is a better predictor of diabetes, while WHtR is a better predictor of MetS in this sample population.