Early emergence of ethnic differences in type 2 diabetes precursors in the UK: the Child Heart and Health Study in England (CHASE Study)

Comparison of the Watson formula and bioimpedance spectroscopy for measuring body volume and calculating kt/V in patients with peritoneal dialysis

CONCLUSION

There were significant differences between Vwat and Vbis and between Kt/Vwat and Kt/Vbis. Kt/Vwat may underestimate small-solute dialysis adequacy in most cases. Kt/Vbis instead of Kt/Vwat could be accounted for in creating individualized dialysis prescriptions if the patient has no obvious clinical symptoms.

Reflections on co-producing an obesity-prevention toolkit for Islamic Religious Settings: a qualitative process evaluation

BACKGROUND

Islamic leaders, staff, and Muslim parents in the UK are supportive of healthy lifestyle intervention delivery through Islamic Religious Settings. Such interventions are necessary given high obesity rates in British South Asian (40%) compared to White British (32%) children of equivalent age. Co-production can facilitate the development of culturally appropriate health interventions, however it can be theoretically and practically challenging, and evaluation of co-production within an Islamic Religious Setting context is lacking. The aim of this study was to examine the feasibility and acceptability of taking a co-production approach to develop an obesity-prevention toolkit for Islamic Religious Settings.

METHODS

An obesity-prevention toolkit for use in Islamic Religious Settings, incorporating physical activity, healthy diet, and organisational change, has been co-produced to be evidence-informed and contextually relevant. A qualitative process evaluation was employed to examine experiences of co-production. Semi-structured interviews (n = 15) and a focus group (n = 5) were conducted with toolkit co-production stakeholders, e.g., subject experts, an Islamic scholar, and Islamic Religious Setting staff. Transcripts were analysed inductively using reflexive thematic analysis.

RESULTS

The analysis revealed four major themes regarding stakeholders' experiences of co-producing a childhood obesity-prevention toolkit for Islamic Religious Settings. These themes are: (1) attitudes towards obesity-prevention through Islamic Religious Settings, (2) benefits of co-production including capacity building and ownership (3) negotiating involvement, power, and perspectives within the co-production process, and (4) the complexities of effective communication in co-production.

CONCLUSION

This study adds to the evidence-base in support of delivering health promotion through faith settings. Taking a co-production approach to develop an obesity-prevention toolkit for Islamic Religious Settings provided benefit to the toolkit product and local stakeholders. The toolkit is currently being implemented across Bradford, UK and there is potential to adapt the toolkit to other geographical contexts, and for evaluating effectiveness for preventing obesity in British Muslim families.

Ancestry, ethnicity, and race: explaining inequalities in cardiometabolic disease

Population differences in cardiometabolic disease remain unexplained. Misleading assumptions over genetic explanations are partly due to terminology used to distinguish populations, specifically ancestry, race, and ethnicity. These terms differentially implicate environmental and biological causal pathways, which should inform their use. Genetic variation alone accounts for a limited fraction of population differences in cardiometabolic disease. Research effort should focus on societally driven, lifelong environmental determinants of population differences in disease. Rather than pursuing population stratifiers to personalize medicine, we advocate removing socioeconomic barriers to receipt of and adherence to healthcare interventions, which will have markedly greater impact on improving cardiometabolic outcomes. This requires multidisciplinary collaboration and public and policymaker engagement to address inequalities driven by society rather than biology per se.

Sick individuals, sick populations revisited: a test of the Rose hypothesis for type 2 diabetes disparities

Introduction

The Rose hypothesis predicts that since genetic variation is greater within than between populations, genetic risk factors will be associated with individuals' risk of disease but not population disparities, and since socioenvironmental variation is greater between than within populations, socioenvironmental risk factors will be associated with population disparities but not individuals' disease risk.

Methods

We used the UK Biobank to test the Rose hypothesis for type 2 diabetes (T2D) ethnic disparities in the UK. Our cohort consists of 26 912 participants from Asian, black and white ethnic groups. Participants were characterised as T2D cases or controls based on the presence or absence of T2D diagnosis codes in electronic health records. T2D genetic risk was measured using a polygenic risk score (PRS), and socioeconomic deprivation was measured with the Townsend Index (TI). The variation of genetic (PRS) and socioeconomic (TI) risk factors within and between ethnic groups was calculated using analysis of variance. Multivariable logistic regression was used to associate PRS and TI with T2D cases, and mediation analysis was used to analyse the effect of PRS and TI on T2D ethnic group disparities.

Results

T2D prevalence differs for Asian 23.34% (OR=5.14, CI=4.68 to 5.65), black 16.64% (OR=3.81, CI=3.44 to 4.22) and white 7.35% (reference) ethnic groups in the UK. Both genetic and socioenvironmental T2D risk factors show greater within (w) than between (b) ethnic group variation: PRS w=64.60%, b=35.40%; TI w=71.18%, b=28.19%. Nevertheless, both genetic risk (PRS OR=1.96, CI=1.87 to 2.07) and socioeconomic deprivation (TI OR=1.09, CI=1.08 to 1.10) are associated with T2D individual risk and mediate T2D ethnic disparities (Asian PRS=22.5%, TI=9.8%; black PRS=32.0%, TI=25.3%).

Conclusion

A relative excess of within-group versus between-group variation does not preclude T2D risk factors from contributing to T2D ethnic disparities. Our results support an integrative approach to health disparities research that includes both genetic and socioenvironmental risk factors.

Cross-sectional study of the associations between circulating vitamin D concentrations and insulin resistance in children aged 9-10 years of South Asian, black African Caribbean and white European origins

BACKGROUND

Lower circulating vitamin D 25-hydroxyvitamin D (25(OH)D) concentrations are associated with higher type 2 diabetes risk in adults, although causality remains uncertain. However, associations between 25(OH)D and type 2 diabetes risk markers in children have been little studied, particularly in ethnic minority populations. We examined whether 25(OH)D concentrations were associated with insulin resistance in children and whether lower 25(OH)D concentrations in South Asians and black African Caribbeans could contribute to their higher insulin resistance.

METHODS

Cross-sectional study of 4650 UK primary school children aged 9-10 years of predominantly South Asian, black African Caribbean and white European ethnicity. Children had fasting blood measurements of circulating 25(OH)D metabolite concentrations, insulin and glucose.

RESULTS

Lower 25(OH)D concentrations were observed in girls, South Asians and black African Caribbeans. In analyses adjusted for age, sex, month, ethnic group and school, circulating 25(OH)D was inversely associated with fasting insulin (-0.38%, 95% CI -0.49% to -0.27%), homoeostasis model assessment (HOMA) insulin resistance (-0.39%, 95% CI -0.50% to -0.28%) and fasting glucose (-0.03%, 95% CI -0.05% to -0.02%) per nmol/L increase in 25(OH)D; associations did not differ between ethnic groups. Ethnic differences in fasting insulin and HOMA insulin resistance (higher among South Asian and black African Caribbeans) were reduced by >40% after adjustment for circulating 25(OH)D concentrations.

CONCLUSION

Circulating vitamin D was inversely associated with insulin resistance in all ethnic groups; higher insulin resistance in South Asian and black African children were partly explained by their lower vitamin D levels. Whether vitamin D supplementation can reduce emerging type 2 diabetes risk needs further evaluation.

Challenges and Barriers to Providing Primary Care to Children of South Asian Origin: Pediatricians' Perspectives

South Asian (SA) Americans have a high risk of metabolic and cardiovascular disease. Prevention efforts should start in childhood and should be culturally appropriate. We sought to understand the challenges and barriers that pediatricians face in providing care for SA children to inform professional education on culturally effective care. Qualitative interviews were conducted with a diverse sample (N = 17) of pediatricians. Challenges reported included feeding problems, inadequate physical activity, and mental health concerns. Communication barriers included parents' anxiety around feeding, influence of grandparents, stigma around mental health, and cultural communication gaps. Effective strategies included clear communication, a gradual approach, ensuring buy-in from grandparents, greater attention to family history, and improved cultural knowledge in pediatrician. Addressing feeding problems was the most mentioned challenge, which is especially concerning given the high chronic disease risk in SAs. Education on culturally appropriate strategies can equip pediatricians to effectively counsel SA families to address these risks.

Are children with obesity at school entry more likely to have a diagnosis of a musculoskeletal condition? Findings from a systematic review

BACKGROUND

Children with obesity at school entry are at increased risk of persistent obesity throughout childhood and adulthood. Little is known about associations with adverse health outcomes with onset during childhood including those affecting the musculoskeletal system. We examined the association between obesity present at school entry and adverse musculoskeletal diagnoses with onset during childhood.

METHODS

We searched three electronic databases to identify longitudinal studies published in English between January 2000 and June 2022 assessing associations between obesity measured at school entry (around age 5 years) and musculoskeletal diagnoses made before age 20 years. Two reviewers screened titles, abstracts and full-text using EPPI-Reviewer software. Bias and quality of eligible studies were appraised using The Quality Assessment tool for Observational Cohort and Cross-sectional studies and findings synthesised.

RESULTS

We identified four eligible studies from 291 unique records, three conducted in Spain and one in Scotland. These studies reported on 1 232 895 children (available data: 51.4% boys; none reported ethnic distribution) with study sample sizes ranging from <2000 to 600 000 and length of follow-up from 2 to 13 years. Quantitative synthesis of findings across these four studies was not possible due to differences in outcomes and effect sizes reported. Children with obesity at school entry were more likely to receive diagnoses of slipped capital femoral epiphysis, back pain, fractures and musculoskeletal complaints made in primary care settings. Included studies were assessed as of 'fair' to 'good' quality.

CONCLUSION

There is good to fair evidence to suggest children with obesity at school entry are more likely to receive a diagnosis of a musculoskeletal condition during childhood. Further research is needed to replicate these findings in ethnically diverse populations and to investigate whether these are causal associations. The implications of this for children's mobility and quality of life and future musculoskeletal health warrants further assessment.

Drawing on Cultural Traditions to Improve Cardiorespiratory Fitness with South Asian Children: A Feasibility Study

Background: South Asian children have a higher prevalence of cardiovascular disease risk factors compared with children of other ethnic backgrounds. Our objective was to explore the feasibility, acceptability, and potential fitness-related impact of a 7-month afterschool Bhangra dance intervention for South Asian children. Methods: We recruited 172 children grades 3 through 6 across 4 elementary schools for an intervention involving twice weekly Bhangra sessions in the school setting. Feasibility and acceptability were defined by recruitment, attendance, and retention metrics. The primary fitness outcome was cardiorespiratory fitness (CRF), measured via shuttle run laps and VO₂ max. Secondary fitness outcomes included musculoskeletal (vertical jump height) and morphological fitness (waist circumference and BMI). Results: Sample size ranged from 28 to 54 participants per school (n = 172); mean attendance rate was 74%; and retention rate was 87%. VO₂ max and shuttle laps increased by 1.4 mL·kg/min [95% confidence interval (CI): 0.93 to 1.84] and by 7.6 (95% CI: 6.11 to 9.08), respectively. Both these improvements remained significant after controlling for sex and age (VO₂ max) and sex and baseline weight (shuttle laps). Musculoskeletal and morphological fitness indices also improved. Conclusions: Findings suggest that an afterschool Bhangra dance intervention is feasible, acceptable, and associated with CRF improvements as well as other indices of physical fitness.

Young-onset diabetes in Asian Indians is associated with lower measured and genetically determined beta cell function

AIMS/HYPOTHESIS

South Asians in general, and Asian Indians in particular, have higher risk of type 2 diabetes compared with white Europeans, and a younger age of onset. The reasons for the younger age of onset in relation to obesity, beta cell function and insulin sensitivity are under-explored.

METHODS

Two cohorts of Asian Indians, the ICMR-INDIAB cohort (Indian Council of Medical Research-India Diabetes Study) and the DMDSC cohort (Dr Mohan's Diabetes Specialties Centre), and one of white Europeans, the ESDC (East Scotland Diabetes Cohort), were used. Using a cross-sectional design, we examined the comparative prevalence of healthy, overweight and obese participants with young-onset diabetes, classified according to their BMI. We explored the role of clinically measured beta cell function in diabetes onset in Asian Indians. Finally, the comparative distribution of a partitioned polygenic score (pPS) for risk of diabetes due to poor beta cell function was examined. Replication of the genetic findings was sought using data from the UK Biobank.

RESULTS

The prevalence of young-onset diabetes with normal BMI was 9.3% amongst white Europeans and 24-39% amongst Asian Indians. In Asian Indians with young-onset diabetes, after adjustment for family history of type 2 diabetes, sex, insulin sensitivity and HDL-cholesterol, stimulated C-peptide was 492 pmol/ml (IQR 353-616, p<0.0001) lower in lean compared with obese individuals. Asian Indians in our study, and South Asians from the UK Biobank, had a higher number of risk alleles than white Europeans. After weighting the pPS for beta cell function, Asian Indians have lower genetically determined beta cell function than white Europeans (p<0.0001). The pPS was associated with age of diagnosis in Asian Indians but not in white Europeans. The pPS explained 2% of the variation in clinically measured beta cell function, and 1.2%, 0.97%, and 0.36% of variance in age of diabetes amongst Asian Indians with normal BMI, or classified as overweight and obese BMI, respectively.

CONCLUSIONS/INTERPRETATION

The prevalence of lean BMI in young-onset diabetes is over two times higher in Asian Indians compared with white Europeans. This phenotype of lean, young-onset diabetes appears driven in part by lower beta cell function. We demonstrate that Asian Indians with diabetes also have lower genetically determined beta cell function.

Could high heat cooking and food processing promoting neo-formed contaminants partially explain the high prevalence of chronic kidney disease in South Asian populations? A hypothesis

BACKGROUND AND AIMS

The occurrence of chronic heart and kidney diseases among the South Asian populations has been rising exponentially over the years. Research has been carried out in the past to explain the increased susceptibility with no resultant strong evidence. Various possible causes have been suggested with a previous hypothesis suggestive of high heat cooking techniques being responsible for increased production of neo-formed contaminants such as advanced glycation end products (AGEs) and trans-fatty acids (TFAs) leading to increased chronic heart diseases among the South Asian diaspora (India, Pakistan, Bangladesh, Sri Lanka in South Asia and overseas). The aim of this study proposes the high-heating cooking techniques and subsequent NFCs also to be responsible for the development of chronic kidney ailments among the South Asians.

METHODS

Review of the literature was conducted to ascertain the burden of accumulation and actions of AGEs and TFAs on kidney structure and functions. The varied high-heat cooking techniques including reheating of oils, food processing and kinds of food sources and their association with increased NFCs production and kidney damage were explored.

RESULTS

Higher NFCs content of AGEs/TFAs in reheated oils at elevated temperatures and TFAs among processed and fast foods of South Asians was associated with elevated diabetic complications and CKDs progression in few animal and human studies but the research on the actual burden of NFCs in the renal tissues of South Asians was lacking.

CONCLUSION

We hypothesize the high heat cooked foods generating increased levels of NFCs to be responsible for the preponderance of higher risk of CKDs among South Asians. Scientific exploration of the hypothesis to obtain quantifiable evidence of NFCs is suggested.

Antihypertensive Medication Use and Its Effects on Blood Pressure and Haemodynamics in a Tri-ethnic Population Cohort: Southall and Brent Revisited (SABRE)

Objectives:

We characterised differences in BP control and use of antihypertensive medications in European (EA), South Asian (SA) and African-Caribbean (AC) people with hypertension and investigated the potential role of type 2 diabetes (T2DM), reduced arterial compliance (C_a), and antihypertensive medication use in any differences.

Methods:

Analysis was restricted to individuals with hypertension [age range 59–85 years; N = 852 (EA = 328, SA = 356, and AC =168)]. Questionnaires, anthropometry, BP measurements, echocardiography, and fasting blood assays were performed. BP control was classified according to UK guidelines operating at the time of the study. Data were analysed using generalised structural equation models, multivariable regression and treatment effect models.

Results:

SA and AC people were more likely to receive treatment for high BP and received a greater average number of antihypertensive agents, but despite this a smaller proportion of SA and AC achieved control of BP to target [age and sex adjusted odds ratio (95% confidence interval) = 0.52 (0.38, 0.72) and 0.64 (0.43, 0.96), respectively]. Differences in BP control were partially attenuated by controlling for the higher prevalence of T2DM and reduced C_a in SA and AC. There was little difference in choice of antihypertensive agent by ethnicity and no evidence that differences in efficacy of antihypertensive regimens contributed to ethnic differences in BP control.

Conclusions:

T2DM and more adverse arterial stiffness are important factors in the poorer BP control in SA and AC people. More effort is required to achieve better control of BP, particularly in UK ethnic minorities.

Type 2 diabetes risks and determinants in second-generation migrants and mixed ethnicity people of South Asian and African Caribbean descent in the UK

AIMS/HYPOTHESIS

Excess risks of type 2 diabetes in UK South Asians (SA) and African Caribbeans (AC) compared with Europeans remain unexplained. We studied risks and determinants of type 2 diabetes in first- and second-generation (born in the UK) migrants, and in those of mixed ethnicity.

METHODS

Data from the UK Biobank, a population-based cohort of ~500,000 participants aged 40-69 at recruitment, were used. Type 2 diabetes was assigned using self-report and HbA1c. Ethnicity was both self-reported and genetically assigned using admixture level scores. European, mixed European/South Asian (MixESA), mixed European/African Caribbean (MixEAC), SA and AC groups were analysed, matched for age and sex to enable comparison. In the frames of this cross-sectional study, we compared type 2 diabetes in second- vs first-generation migrants, and mixed ethnicity vs non-mixed groups. Risks and explanations were analysed using logistic regression and mediation analysis, respectively.

RESULTS

Type 2 diabetes prevalence was markedly elevated in SA (599/3317 = 18%) and AC (534/4180 = 13%) compared with Europeans (140/3324 = 4%). Prevalence was lower in second- vs first-generation SA (124/1115 = 11% vs 155/1115 = 14%) and AC (163/2200 = 7% vs 227/2200 = 10%). Favourable adiposity (i.e. lower waist/hip ratio or BMI) contributed to lower risk in second-generation migrants. Type 2 diabetes in mixed populations (MixESA: 52/831 = 6%, MixEAC: 70/1045 = 7%) was lower than in comparator ethnic groups (SA: 18%, AC: 13%) and higher than in Europeans (4%). Greater socioeconomic deprivation accounted for 17% and 42% of the excess type 2 diabetes risk in MixESA and MixEAC compared with Europeans, respectively. Replacing self-reported with genetically assigned ethnicity corroborated the mixed ethnicity analysis.

CONCLUSIONS/INTERPRETATION

Type 2 diabetes risks in second-generation SA and AC migrants are a fifth lower than in first-generation migrants. Mixed ethnicity risks were markedly lower than SA and AC groups, though remaining higher than in Europeans. Distribution of environmental risk factors, largely obesity and socioeconomic status, appears to play a key role in accounting for ethnic differences in type 2 diabetes risk.

Type 2 diabetes burden among migrants in Europe: unravelling the causal pathways

European populations are ethnically and culturally diverse due to international migration. Evidence indicates large ethnic inequalities in the prevalence of type 2 diabetes. This review discusses the burden of type 2 diabetes and its related complications, and the potential explanatory mechanisms among migrants in Europe. The current available data suggest that the rate of type 2 diabetes is higher in all migrant groups and that they develop this disease at an earlier age than the host European populations. The level of diabetes awareness among migrant populations is high, but glycaemic control remains suboptimal compared with Europeans. The culturally adapted lifestyle modification intervention trials to prevent type 2 diabetes mainly focus on South Asian adults in Europe. Diabetes-related microvascular and macrovascular complications remain a major burden among migrant populations in Europe. Earlier studies found higher mortality rates among migrants, but recent studies seem to suggest a shifting trend in favour of first-generation migrants. However, the extent of the burden of type 2 diabetes varies across migrant groups and European countries. Despite the higher burden of type 2 diabetes among migrants, the key underlying factors are not well understood mainly due to limited investment in basic science research and development of prospective cohort studies. We hypothesise that the underlying risk factors for the high burden of type 2 diabetes and its related complications in migrants are multifaceted and include pre-migration factors, post-migration factors and genetic predispositions. Given the multi-ethnic nature of the current European population, there is a clear need for investment in research among migrant populations to gain insight into factors driving the high burden of type 2 diabetes and related complications to facilitate prevention and treatment efforts in Europe.

Completeness and representativeness of body mass index in children's electronic general practice records: Linked cross-sectional study in an ethnically-diverse urban population in the United Kingdom

OBJECTIVE

To assess completeness and accuracy of children's body mass index (BMI) recorded in general practice electronic health records (GP-EHRs).

METHODS

We linked National Child Measurement Programme (NCMP) records from 29 839 5-year-olds and 26 660 11-year-olds attending state schools in inner London to GP-EHRs (95% linked; 49.1% girls). We estimated adjusted odds (aOR) of at least one GP-BMI record by sex, ethnic background, area-level deprivation, weight-status and long-term conditions. We examined within-child BMI differences and compared obesity prevalence from these sources.

RESULTS

10.5% (2964/28330) and 26.0% (6598/25365) of 5- and 11-year-olds respectively had at least one GP-BMI record. Underweight (aOR;95% CI:1.71;1.34,2.19), obesity (1.45;1.27,1.65), South Asian background (1.55;1.38,1.74), presence of a long-term condition (8.15;7.31,9.10), and residence in deprived areas (Wald statistic 38.73; P-value<0.0001) were independently associated with at least one GP-BMI record. NCMP-BMI and GP-BMI differed by +0.45(95% Limits of Agreement -1.60,+2.51) and + 0.16(-2.86,+3.18) in 5- and 11-year-olds, respectively. The prevalence of obesity based on GP-BMI was 18.2%(16.1,20.5) and 35.9%(33.9,38.0) in 5- and 11-year-olds respectively, compared to 12.9%(12.5,13.3) and 26.9%(26.4,27.4) based on NCMP-BMI.

CONCLUSION

Child BMI is not comprehensively recorded in urban general practice. Linkage to school measurement records is feasible and enables assessment of health outcomes of obesity.

Comparison of the performances of survival analysis regression models for analysis of conception modes and risk of type-1 diabetes among 1985-2015 Swedish birth cohort

The goal is to examine the risk of conception mode-type-1 diabetes using different survival analysis modelling approaches and examine if there are differentials in the risk of type-1 diabetes between children from fresh and frozen-thawed embryo transfers. We aimed to compare the performances and fitness of different survival analysis regression models with the Cox proportional hazard (CPH) model used in an earlier study. The effect of conception modes and other prognostic factors on type-1 diabetes among children conceived either spontaneously or by assisted reproductive technology (ART) and its sub-groups was modelled in the earlier study. We used the information on all singleton children from the Swedish Medical Birth Register hosted by the Swedish National Board of Health and Welfare, 1985 to 2015. The main explanatory variable was the mode of conception. We applied the CPH, parametric and flexible parametric survival regression (FPSR) models to the data at 5% significance level. Loglikelihood, Akaike and Bayesian information criteria were used to assess model fit. Among the 3,138,540 singletons, 47,938 (1.5%) were conceived through ART (11,211 frozen-thawed transfer and 36,727 fresh embryo transfer). In total, 18,118 (0.58%) of the children had type-1 diabetes, higher among (0.58%) those conceived spontaneously than the ART-conceived (0.42%). The median (Interquartile range (IQR)) age at onset of type-1 diabetes among spontaneously conceived children was 10 (14-6) years, 8(5-12) for ART, 6 (4-10) years for frozen-thawed embryo transfer and 9 (5-12) years for fresh embryo transfer. The estimates from the CPH, FPSR and parametric PH models are similar. There was no significant difference in the risk of type-1 diabetes among ART- and spontaneously conceived children; FPSR: (adjusted Hazard Ratio (aHR) = 1.070; 95% Confidence Interval (CI):0.929-1.232, p = 0.346) vs CPH: (aHR = 1.068; 95%CI: 0.927-1.230, p = 0.361). A sub-analysis showed that the adjusted hazard of type-1 diabetes was 37% (aHR = 1.368; 95%CI: 1.013-1.847, p = 0.041) higher among children from frozen-thawed embryo transfer than among children from spontaneous conception. The hazard of type-1 diabetes was higher among children whose mothers do not smoke (aHR = 1.296; 95%CI:1.240-1.354, p<0.001) and of diabetic mothers (aHR = 6.419; 95%CI:5.852-7.041, p<0.001) and fathers (aHR = 8.808; 95%CI:8.221-9.437, p<0.001). The estimates from the CPH, parametric models and the FPSR model were close. This is an indication that the models performed similarly and any of them can be used to model the data. We couldn't establish that ART increases the risk of type-1 diabetes except when it is subdivided into its two subtypes. There is evidence of a greater risk of type-1 diabetes when conception is through frozen-thawed transfer.

Is child weight status correctly reported to parents? Cross-sectional analysis of National Child Measurement Programme data using ethnic-specific BMI adjustments

Background

BMI underestimates and overestimates body fat in children from South Asian and Black ethnic groups, respectively.

Methods

We used cross-sectional NCMP data (2015–17) for 38 270 children in three inner-London local authorities: City & Hackney, Newham and Tower Hamlets (41% South Asian, 18.8% Black): 20 439 4–5 year-olds (48.9% girls) and 17 831 10–11 year-olds (49.1% girls). We estimated the proportion of parents who would have received different information about their child’s weight status, and the area-level prevalence of obesity—defined as ≥98th centile—had ethnic-specific BMI adjustments been employed in the English National Child Measurement Programme (NCMP).

Results

Had ethnic-specific adjustment been employed, 19.7% (3112/15 830) of parents of children from South Asian backgrounds would have been informed that their child was in a heavier weight category, and 19.1% (1381/7217) of parents of children from Black backgrounds would have been informed that their child was in a lighter weight category. Ethnic-specific adjustment increased obesity prevalence from 7.9% (95% CI: 7.6, 8.3) to 9.1% (8.7, 9.5) amongst 4–5 year-olds and from 17.5% (16.9, 18.1) to 18.8% (18.2, 19.4) amongst 10–11 year-olds.

Conclusions

Ethnic-specific adjustment in the NCMP would ensure equitable categorization of weight status, provide correct information to parents and support local service provision for families.

Delivering a childhood obesity prevention intervention using Islamic religious settings in the UK: What is most important to the stakeholders?

Ten per cent of the childhood population in the UK are of South Asian (SA) origin. Within this population, over 40% are living with overweight or obesity. The majority of SA children are Muslim and attend Islamic religious settings (IRS) daily after school. Because of their reach and influence, IRS may be an appropriate channel for obesity prevention initiatives. We conducted 20 in-depth interviews with parents of children attending IRS, 20 with Islamic leaders, and 3 focus group discussions with 26 managers and workers of IRS in Bradford and Birmingham. Topic guides were developed, interviews and focus group discussions were audio-recorded, transcribed, and analysed thematically. Muslim parents, Islamic leaders and IRS staff were supportive of the delivery of obesity prevention interventions for children using IRS. Participants identified important components of an intervention including: Prophet Muhammad (PBUH) as a role model for healthy lifestyle; healthy diet, physical activity, and organisational behaviour change within IRS. Participants suggested that Islamic narrative on healthy diet and physical fitness could increase delivery uptake. Staff showed willingness to conduct physical activity sessions for boys and girls. Barriers for the intervention delivery were poor funding systems and time constraints for staff. All participant groups thought that it would be possible to deliver a childhood obesity prevention intervention. Interventions should be co-designed, culturally and religiously sensitive and combine the scientific guidelines on healthy living with Islamic narrative on importance of healthy diet consumption and physical activity.

The trans-ancestral genomic architecture of glycemic traits

Glycemic traits are used to diagnose and monitor type 2 diabetes and cardiometabolic health. To date, most genetic studies of glycemic traits have focused on individuals of European ancestry. Here we aggregated genome-wide association studies comprising up to 281,416 individuals without diabetes (30% non-European ancestry) for whom fasting glucose, 2-h glucose after an oral glucose challenge, glycated hemoglobin and fasting insulin data were available. Trans-ancestry and single-ancestry meta-analyses identified 242 loci (99 novel; P < 5 × 10-8), 80% of which had no significant evidence of between-ancestry heterogeneity. Analyses restricted to individuals of European ancestry with equivalent sample size would have led to 24 fewer new loci. Compared with single-ancestry analyses, equivalent-sized trans-ancestry fine-mapping reduced the number of estimated variants in 99% credible sets by a median of 37.5%. Genomic-feature, gene-expression and gene-set analyses revealed distinct biological signatures for each trait, highlighting different underlying biological pathways. Our results increase our understanding of diabetes pathophysiology by using trans-ancestry studies for improved power and resolution.

Stand Out in Class: Investigating the Potential Impact of a Sit-Stand Desk Intervention on Children's Sitting and Physical Activity during Class Time and after School

Sedentary behaviour (sitting) is a risk factor for adverse health outcomes. The classroom environment has traditionally been associated with prolonged periods of sitting in children. The aim of this study was to examine the potential impact of an environmental intervention, the addition of sit–stand desks in the classroom, on school children’s sitting and physical activity during class time and after school. The ‘Stand Out in Class’ pilot trial was a two-arm cluster randomised controlled trial conducted in eight primary schools with children from a mixed socioeconomic background. The 4.5 month environmental intervention modified the physical (six sit–stand desks replaced standard desks) and social (e.g., teachers’ support) environment. All children wore activPAL and ActiGraph accelerometers for 7 days at baseline and follow-up. In total 176 children (mean age = 9.3 years) took part in the trial. At baseline, control and intervention groups spent more than 65% of class time sitting, this changed to 71.7% and 59.1% at follow-up, respectively (group effect p < 0.001). The proportion of class time spent standing and stepping, along with the proportion of time in light activity increased in the intervention group and decreased in the control group. There was no evidence of any compensatory effects from the intervention after school. Incorporating sit–stand desks to change the classroom environment at primary school appears to be an acceptable strategy for reducing children’s sedentary behaviour and increasing light activity especially during class time. Trial registration: ISRCTN12915848 (registered: 09/11/16).

Cardio-Metabolic Risk Factors in Scottish South Asian and Caucasian Youth

(1) Background: Scotland has one of the highest rates of obesity in the Western World, it is well established that poor weight profiles, and particularly abdominal obesity, is strongly associated with Type II diabetes and cardiovascular diseases. Whether these associations are apparent in ethnic population groups in Scotland is unclear. The purpose of this study was to examine the associations between different measures of fatness with clustered cardio metabolic risk factors between Scottish South Asian adolescents and Scottish Caucasian adolescents; (2) Methods: A sample of 208 Caucasian adolescents and 52 South Asian adolescents participated in this study. Stature, waist circumference, body mass index, blood pressure, physical activity, and cardiovascular disease (CVD) risk were measured; (3) Results: Significant, partial correlations in the South Asian cohort between body mass index (BMI) and individual risk factors were generally moderate. However, correlations between Waist circumference (WC) and individual risk factors were significant and strong. In the Caucasian cohort, a significant yet weak correlation between WC and total cholesterol (TG) was noted although no other associations were evident for either WC or BMI. Multiple regression analysis revealed that both BMI and WC were positively associated with CCR (p < 0.01) in the South Asian group and with the additional adjustment of either WC or BMI, the independent associations with clustered cardio-metabolic risk (CCR) remained significant (p < 0.005); (4) Conclusions: No positive relationships were found between BMI, WC, and CCR in the Caucasian group. Strong and significant associations between measures of fatness and metabolic risk were evident in Scottish South Asian adolescents.

Diabetes and cardiometabolic risk in South Asian youth: A review

South Asians are at increased risk for developing type 2 diabetes and cardiovascular disease at lower body mass index compared to other ancestral groups. Many factors contribute to this increased risk, including genetics, maternal-fetal factors, diet, fitness, body composition, and unique pathophysiology. Increased cardiometabolic risk is also seen at younger ages in South Asian individuals as compared to their White counterparts. This risk persists in migrant communities outside of South Asia. With the growing prevalence of obesity, diabetes, and cardiovascular disease in the South Asian population, it is imperative that we had better understand the mechanisms underlying this increased risk and implement strategies to address this growing public health problem during childhood and adolescence.

Impacts of a Standing Desk Intervention within an English Primary School Classroom: A Pilot Controlled Trial

Traditional classroom furniture dictates that children predominantly sit during class time. This study evaluated the impact of providing standing desks within a deprived UK primary school setting over 8 months using mixed-method approaches. All children within a Year 5 class (9–10-year-olds, n = 30) received an adjustable sit–stand desk, while another Year 5 class (n = 30) in a nearby school retained traditional furniture as a control classroom. At baseline, 4 months, and 8 months, activPAL monitors (PAL Technologies, Glasgow, UK) were worn for 7 days to provide time spent sitting and standing. Behavior-related mental health, musculoskeletal discomfort surveys, and a cognitive function test battery were also completed at all three timepoints. Intervention experiences from pupils and the teacher were captured using focus groups, interviews, and classroom observations. At both 4 months and 8 months, multi-level models revealed a reduction in class time sitting in the intervention group compared to the control group ((β (95%CI) 4 months −25.3% (−32.3, −18.4); 8 months −19.9% (−27.05, −12.9)). Qualitative data revealed challenges to teaching practicalities and a gradual decline in behavior-related mental health was observed (intervention vs. control: 4 months +5.31 (+2.55, +8.08); 8 months +7.92 (+5.18, +10.66)). Larger trials within similar high-priority settings are required to determine the feasibility and cost-effectiveness of providing standing desks to every child in the classroom.

COVID-19 and ethnicity: A novel pathophysiological role for inflammation

INTRODUCTION

There have been recent mounting concerns regarding multiple reports stating a significantly elevated relative-risk of COVID-19 mortality amongst the Black and Minority Ethnic (BAME) population. An urgent national enquiry investigating the possible reasons for this phenomenon has been issued in the UK. Inflammation is at the forefront of COVID-19 research as disease severity appears to correlate with pro-inflammatory cytokine dysregulation. This narrative review aims to shed light on the novel, pathophysiological role of inflammation in contributing towards the increased COVID-19 mortality risk amongst the BAME population.

METHODS

Searches in PubMed, Medline, Scopus, medRxiv and Google Scholar were performed to identify articles published in English from inception to 18th June 2020. These databases were searched using keywords including: 'COVID-19' or 'Black and Minority Ethnic' or 'Inflammation'. A narrative review was synthesized using these included articles.

RESULTS

We suggest a novel pathophysiological mechanism by which acute inflammation from COVID-19 may augment existing chronic inflammation, in order to potentiate a 'cytokine storm' and thus the more severe disease phenotype observed in the BAME population. Obesity, insulin resistance, cardiovascular disease, psychological stress, chronic infections and genetic predispositions are all relevant factors which may be contributing to elevated chronic systemic inflammation amongst the BAME population.

CONCLUSION

Overall, this review provides early insights and directions for ongoing research regarding the pathophysiological mechanisms that may explain the severe COVID-19 disease phenotype observed amongst the BAME population. We suggest 'personalization' of chronic disease management, which can be used with other interventions, in order to tackle this.

Sit–stand desks to reduce sedentary behaviour in 9- to 10-year-olds: the Stand Out in Class pilot cluster RCT

Background

Sedentary behaviour (sitting) is a highly prevalent negative health behaviour, with individuals of all ages exposed to environments that promote prolonged sitting. The school classroom represents an ideal setting for environmental change through the provision of sit–stand desks.

Objectives

The aim of this study was to undertake a pilot cluster randomised controlled trial of the introduction of sit–stand desks in primary school classrooms, to inform a definitive trial. Objectives included providing information on school and participant recruitment and retention, acceptability of the intervention, and outcome measures. A preliminary estimate of the intervention’s effectiveness on the proposed primary outcome (change in weekday sitting time) for inclusion in a definitive trial was calculated, along with a preliminary assessment of potential cost-effectiveness. A full process evaluation was also undertaken.

Design

A two-armed pilot cluster randomised controlled trial with economic and qualitative evaluations. Schools were randomised on a 1 : 1 basis to the intervention (n = 4) or control (n = 4) trial arms.

Setting

Primary schools in Bradford, West Yorkshire, UK.

Participants

Children in Year 5 (i.e. aged 9–10 years).

Intervention

Six sit–stand desks replaced three standard desks (sitting six children) in the intervention classrooms for 4.5 months. Teachers were encouraged to ensure that all pupils were exposed to the sit–stand desks for at least 1 hour per day, on average, using a rotation system. Schools assigned to the control arm continued with their usual practice.

Main outcome measures

Trial feasibility outcomes included school and participant recruitment and attrition, acceptability of the intervention, and acceptability of and compliance with the proposed outcome measures [including weekday sitting measured using activPAL™ (PAL Technologies Ltd, Glasgow, UK) accelerometers, physical activity, adiposity, blood pressure, cognitive function, musculoskeletal comfort, academic progress, engagement and behaviour].

Results

Thirty-three per cent of schools approached and 75% (n = 176) of eligible children took part. At the 7-month follow-up, retention rates were 100% for schools and 97% for children. Outcome measure completion rates ranged from 63% to 97%. A preliminary estimate of intervention effectiveness, from a weighted linear regression model (adjusting for baseline sitting time and wear time) revealed a mean difference in change in sitting of –30.6 minutes per day (95% confidence interval –56.42 to –4.84 minutes per day) between the intervention and control trial arms. The process evaluation revealed that the intervention, recruitment and evaluation procedures were acceptable to teachers and children, with the exception of minor issues around activPAL attachment. A preliminary within-trial economic analysis revealed no difference between intervention and control trial arms in health and education resource use or outcomes. Long-term modelling estimated an unadjusted incremental cost-effectiveness ratio of Stand Out in Class of £78,986 per quality-adjusted life-year gained.

Conclusion

This study has provided evidence of the acceptability and feasibility of the Stand Out in Class intervention and evaluation methods. Preliminary evidence suggests that the intervention may have a positive direction of effect on weekday sitting time, which warrants testing in a full cluster randomised controlled trial. Lessons learnt from this trial will inform the planning of a definitive trial.

Trial registration

Current Controlled Trials ISRCTN12915848.

Funding

This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 8, No. 8. See the NIHR Journals Library website for further project information.

Stand Out in Class: restructuring the classroom environment to reduce sitting time - findings from a pilot cluster randomised controlled trial

Background

Excessive sedentary behaviour (sitting) is a risk factor for poor health in children and adults. Incorporating sit-stand desks in the classroom environment has been highlighted as a potential strategy to reduce children’s sitting time. The primary aim of this study was to examine the feasibility of conducting a cluster randomised controlled trial (RCT) of a sit-stand desk intervention within primary school classrooms.

Methods

We conducted a two-armed pilot cluster RCT involving 8 primary schools in Bradford, United Kingdom. Schools were randomised on a 1:1 basis to the intervention or usual practice control arm. All children (aged 9–10 years) in participating classes were eligible to take part. Six sit-stand desks replaced three standard desks (sitting 6 children) in the intervention classrooms for 4.5-months. Teachers were encouraged to use a rotation system to ensure all pupils were exposed to the sit-stand desks for > 1 h/day on average. Trial feasibility outcomes (assessed using quantitative and qualitative measures) included school and participant recruitment and attrition, intervention and outcome measure completion rates, acceptability, and preliminary effectiveness of the intervention for reducing sitting time. A weighted linear regression model compared changes in weekday sitting time (assessed using the activPAL accelerometer) between trial arms.

Results

School and child recruitment rates were 33% (n = 8) and 75% (n = 176). At follow-up, retention rates were 100% for schools and 97% for children. Outcome measure completion rates ranged from 63 to 97%. A preliminary estimate of intervention effectiveness revealed a mean difference in change in sitting of − 30.6 min/day (95% CI: − 56.42 to − 4.84) in favour of the intervention group, after adjusting for baseline sitting and wear time. Qualitative measures revealed the intervention and evaluation procedures were acceptable to teachers and children, except for some problems with activPAL attachment.

Conclusion

This study provides evidence of the acceptability and feasibility of a sit-stand desk intervention and evaluation methods. Preliminary evidence suggests the intervention showed potential in reducing children’s weekday sitting but some adaptations to the desk rotation system are needed to maximize exposure. Lessons learnt from this trial will inform the planning of a definitive trial.

Trial registration

ISRCTN12915848 (registered: 09/11/16).

Ethnic Differences in Functional Limitations by Age Across the Adult Life Course

Background

Despite compelling evidence from the United States of ethnic inequalities in physical functioning and ethnic differences in risk factors for poor physical functioning, very little is known about ethnic differences in the United Kingdom. Furthermore, the life stage at which these ethnic differentials are first observed has not been examined.

Methods

Using cross-sectional data from Wave 1 of the UK Household Longitudinal Study (UKHLS), we compared self-reported physical functioning among 35,816 White British, 4,450 South Asian and 2,512 African Caribbean men and women across different stages of adulthood (young adulthood, early middle age, late middle age, older age). Regression analyses examined ethnic differences in functional limitations, with adjustment for socioeconomic and clinical covariates. Ethnicity by sex and ethnicity by age-group interactions were examined, and subgroup heterogeneity was explored.

Results

Compared with White British adults over the age of 60, older South Asian men and women reported higher odds of functional limitations (odds ratio [OR] 2.77 [95% confidence interval {CI}: 2.00–3.89] and OR 3.99 [2.61–6.10], respectively); these ethnic differentials were observed as early as young adulthood. Young African Caribbean men had lower odds of functional limitations than White British men (OR 0.56 [0.34–0.94]), yet African Caribbean women reported higher odds of functional limitations in older age (OR 1.84 [1.21–2.79]).

Conclusions

There is an elevated risk of functional limitations relating to ethnicity, even in young adulthood where the impact on future health and socioeconomic position is considerable. When planning and delivering health care services to reduce ethnic inequalities in functional health, the intersectionality with age and sex should be considered.

Type 2 diabetes does not account for ethnic differences in exercise capacity or skeletal muscle function in older adults

AIMS/HYPOTHESIS

The aim of this study was to compare exercise capacity, strength and skeletal muscle perfusion during exercise, and oxidative capacity between South Asians, African Caribbeans and Europeans, and determine what effect ethnic differences in the prevalence of type 2 diabetes has on these functional outcomes.

METHODS

In total, 708 participants (aged [mean±SD] 73 ± 7 years, 56% male) were recruited from the Southall and Brent Revisited (SABRE) study, a UK population-based cohort comprised of Europeans (n = 311) and South Asian (n = 232) and African Caribbean (n = 165) migrants. Measurements of exercise capacity using a 6 min stepper test (6MST), including measurement of oxygen consumption ([Formula: see text]) and grip strength, were performed. Skeletal muscle was assessed using near infrared spectroscopy (NIRS); measures included changes in tissue saturation index (∆TSI%) with exercise and oxidative capacity (muscle oxygen consumption recovery, represented by a time constant [τ]). Analysis was by multiple linear regression.

RESULTS

When adjusted for age and sex, in South Asians and African Caribbeans, exercise capacity was reduced compared with Europeans ([Formula: see text] [ml min-1 kg-1]: β = -1.2 [95% CI -1.9, -0.4], p = 0.002, and β -1.7 [95% CI -2.5, -0.8], p < 0.001, respectively). South Asians had lower and African Caribbeans had higher strength compared with Europeans (strength [kPa]: β = -9 [95% CI -12, -6), p < 0.001, and β = 6 [95% CI 3, 9], p < 0.001, respectively). South Asians had greater decreases in TSI% and longer τ compared with Europeans (∆TSI% [%]: β = -0.9 [95% CI -1.7, -0.1), p = 0.024; τ [s]: β = 11 [95% CI 3, 18], p = 0.006). Ethnic differences in [Formula: see text] and grip strength remained despite adjustment for type 2 diabetes or HbA1c (and fat-free mass for grip strength). However, the differences between Europeans and South Asians were no longer statistically significant after adjustment for other possible mediators or confounders (including physical activity, waist-to-hip ratio, cardiovascular disease or hypertension, smoking, haemoglobin levels or β-blocker use). The difference in ∆TSI% between Europeans and South Asians was marginally attenuated after adjustment for type 2 diabetes or HbA1c and was also no longer statistically significant after adjusting for other confounders; however, τ remained significantly longer in South Asians vs Europeans despite adjustment for all confounders.

CONCLUSIONS/INTERPRETATION

Reduced exercise capacity in South Asians and African Caribbeans is unexplained by higher rates of type 2 diabetes. Poorer exercise tolerance in these populations, and impaired muscle function and perfusion in South Asians, may contribute to the higher morbidity burden of UK ethnic minority groups in older age.

Objectively-measured sedentary time and physical activity in a bi-ethnic sample of young children: variation by socio-demographic, temporal and perinatal factors

Background

Evidence suggests that South Asian school-aged children and adults are less active compared to the white British population. It is unknown if this generalises to young children. We aimed to describe variability in levels of physical activity and sedentary time in a bi-ethnic sample of young children from a deprived location.

Methods

This observational study included 202 South Asian and 140 white British children aged 1.5 to 5y, who provided 3181 valid days of triaxial accelerometry (Actigraph GT3X+). Variability in sedentary time and physical activity levels were analysed by linear multilevel modelling. Logistic multilevel regression was used to identify factors associated with physical inactivity (failing to perform ≥180 min of total physical activity including ≥60 min moderate-to-vigorous physical activity (MVPA) per day).

Results

There were no significant ethnic differences in the overall levels of behaviours; South Asian and white British children spent half of daily time sedentary, just over 40% in light physical activity, and the remaining 7.5 to 8% of time in MVPA. Sedentary time was lower and physical activity levels were higher in older children, and levels of MVPA and vector magnitude counts per minute (CPM) were higher on weekends compared to weekdays. In South Asian children, sedentary time was lower on weekends. Sedentary time was lower and physical activity levels were higher in spring compared to winter in white British children, and in all seasons compared to winter in South Asian children. South Asian children born at high birth weight performed more MVPA, and in both ethnicities there was some evidence that children with older mothers were more sedentary and less active. Sedentary time was higher and light physical activity was lower in South Asian children in the highest compared to the lowest income families. South Asian girls performed less MVPA, registered fewer vector magnitude CPM, and were 3.5 times more likely to be physically inactive than South Asian boys.

Conclusions

Sedentary time and physical activity levels vary by socio-demographic, temporal and perinatal characteristics in young children from a deprived location. South Asian girls have the most to gain from efforts to increase physical activity levels.

Trial registration

The Pre-schoolers in the Playground (PiP) pilot randomized controlled trial is registered with the ISRCTN (ISRCTN54165860; http://www.isrctn.com).

Waist circumference centiles for UK South Asian children

OBJECTIVES

To develop waist circumference (WC) centile curves for UK South Asian children, to make comparisons with published centiles for British, indigenous Indian and Pakistani children, as well as to make anthropometric comparisons with their UK white peers.

DESIGN

Cross-sectional study.

SETTING

School-aged children from London boroughs (main measures: 2004-2007).

PARTICIPANTS

1562 (652 boys, 910 girls) UK South Asian and 1120 (588 boys, 532 girls) UK white children aged 4.0-13.9 years.

INTERVENTIONS

WC, height, weight and body mass index (BMI).

MAIN OUTCOME MEASURES

The outcome measures were smoothed WC centile curves, constructed using the LMS (L = skewness, M = median, S = coefficient of variation) method. SD scores (SDS) were generated using UK90 and British (WC) growth references.

RESULTS

WC increased with age for both sexes, rising more steeply at the upper centiles after the age of 6 years. Overall, UK South Asian children, similar to indigenous South Asian populations, had higher WC values than the British WC references. However, compared with their UK white peers, UK South Asian children had significantly (p<0.001) lower mean WC (UK white SDS=0.74 and SDS=0.64 vs UK South Asian SDS=0.32 and SDS=0.21 for boys and girls, respectively). Obesity prevalence was greater using WC than BMI for both ethnicities. At the 90th centile, for UK South Asian children, prevalence was 21.5% vs 24.4% for boys and 17% vs 24.5% for girls based on BMI and WC, respectively.

CONCLUSIONS

These curves represent the first WC centiles for UK South Asian children up to the age of 14 years. With a continued rise in childhood obesity, they provide a useful historical control for future comparisons.

activPAL-measured sitting levels and patterns in 9-10 years old children from a UK city

BACKGROUND

There is insufficient evidence of sitting time in UK children from validated objective measures. This study explored sitting patterns in primary school children from Bradford, UK, using the validated activPAL inclinometer.

METHODS

Overall, 79 children (9.8 (SD 0.3) years old, 52% boys; 70% South Asian) wore activPALs for 7 days. Total sitting time, sitting time accumulated in different bout lengths, and the proportion of wear time spent in these variables were explored and compared across different periods of the week.

RESULTS

Children spent 614 ± 112 (median ± IQR) min/day on school days and 690 ± 150 min/day on weekend days sitting. The proportion of time spent sitting was significantly higher on weekend days compared to school days (mean±SD: 74 ± 10% versus 68 ± 8%,P < 0.001), as was the proportion of time accumulated in >30 min sitting bouts (mean±CI: 28 ± 27-33% versus 20 ± 20-22%, P < 0.001). The proportion of time spent sitting after school was significantly higher than during school time (mean±SD: 70 ± 8.4% versus 63 ± 8.3%,P < 0.001), as was the proportion of time spent in prolonged (>30 min) sitting bouts (mean±CI: 19 ± 16-22% versus 11 ± 10-14%, P < 0.001).

CONCLUSIONS

Children spent large proportions of their waking day sitting, often accumulated in prolonged uninterrupted bouts and particularly after school and on weekends. Interventions to reduce sitting time in children are urgently needed.

Does the neighborhood food environment contribute to ethnic inequalities in fast-food intake? findings from the ORiEL study

The neighborhood food environment may contribute to ethnic inequalities in diet. Using data from 1389 participants in the Olympic Regeneration in East London (UK) study we assessed whether ethnic inequalities in neighborhood availability of fast-food restaurants mediated and/or modified ethnic inequalities in fast-food intake in 13–15 year-old adolescents. We compared the proportion of high fast-food consumers across “White UK”, “Black”, and “South Asian” ethnic categories. We used Poisson regression with robust standard errors to assess direct and indirect effects (mediation analysis) and risk ratios of high fast-food intake by ethnic category and fast-food restaurant availability level (effect measure modification analysis). There were ethnic inequalities in high fast-food intake, with risk ratios in adolescents of Black and South Asian background of 1.53 (95% CI: 1.25, 1.87) and 1.71 (95% CI: 1.41, 2.07) respectively compared to White UK participants. We found no evidence of a mediating effect by fast-food restaurant availability, but found some evidence of effect measure modification: ethnic inequalities in fast-food intake were largest in neighborhoods lacking fast-food restaurants, and narrowed as availability increased. Future research should explore why ethnic minorities are more likely to be high fast-food consumers than the majority ethnic group, especially when fast-food restaurant availability is lowest.

Differences in Pregnancy Metabolic Profiles and Their Determinants between White European and South Asian Women: Findings from the Born in Bradford Cohort

There is widespread metabolic disruption in women upon becoming pregnant. South Asians (SA) compared to White Europeans (WE) have more fat mass and are more insulin-resistant at a given body mass index (BMI). Whether these are reflected in other gestational metabolomic differences is unclear. Our aim was to compare gestational metabolic profiles and their determinants between WE and SA women. We used data from a United Kingdom (UK) cohort to compare metabolic profiles and associations of maternal age, education, parity, height, BMI, tricep skinfold thickness, gestational diabetes (GD), pre-eclampsia, and gestational hypertension with 156 metabolic measurements in WE (n = 4072) and SA (n = 4702) women. Metabolic profiles, measured in fasting serum taken between 26–28 weeks gestation, were quantified by nuclear magnetic resonance. Distributions of most metabolic measures differed by ethnicity. WE women had higher levels of most lipoprotein subclasses, cholesterol, glycerides and phospholipids, monosaturated fatty acids, and creatinine but lower levels of glucose, linoleic acid, omega-6 and polyunsaturated fatty acids, and most amino acids. Higher BMI and having GD were associated with higher levels of several lipoprotein subclasses, triglycerides, and other metabolites, mostly with stronger associations in WEs. We have shown differences in gestational metabolic profiles between WE and SA women and demonstrated that associations of exposures with these metabolites differ by ethnicity.

Ethnicity and Type 2 diabetes in the UK

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.

Accounting for height in indices of body composition during childhood and adolescence

Correlations of body composition with height vary by age and sex during childhood. Standard approaches to accounting for height in measures of body composition (dividing by height (in meters)2) do not take this into account. Using measures of total body mass (TBM), fat mass (FM) and fat free mass (FFM) at ages nine, 11, 13, 15 and 18 years from a longitudinal UK cohort study (ALSPAC), we calculated indices of body composition at each age by dividing measures by height (in meters)2. We then produced age-and sex-specific powers of height using allometric regressions and calculated body composition indices by dividing measures by height raised to these powers. TBM, FM and FFM divided by height2 were correlated with height up-to age 11 in females. In males, TBM and FM divided by height2 were correlated with height up-to age 15 years while FM divided by height2 was correlated with height up-to age 11 years. Indices of body composition using age-and sex-specific powers were not correlated with height at any age. In early life, age-and sex-specific powers of height, rather than height in meters2, should be used to adjust body composition for height when measures of adiposity/mass independent of height are required.

Exploring the use of adjusted body mass index thresholds based on equivalent insulin resistance for defining overweight and obesity in UK South Asian children

Background

Body mass index (BMI) overweight/obesity thresholds in South Asian (SA) adults, at equivalent type-2 diabetes risk are lower than for white Europeans (WE). We aimed to define adjusted overweight/obesity thresholds for UK–SA children based on equivalent insulin resistance (HOMA-IR) to WE children.

Methods

In 1138 WE and 1292 SA children aged 9.0–10.9 years, multi-level regression models quantified associations between BMI and HOMA-IR by ethnic group. HOMA-IR levels for WE children were calculated at established overweight/obesity thresholds (at 9.5 years and 10.5 years), based on UK90 BMI cut-offs. Quantified associations in SA children were then used to estimate adjusted SA weight-status thresholds at the calculated HOMA-IR levels.

Results

At 9.5 years, current WE BMI overweight and obesity thresholds were 19.2 kg/m², 21.3 kg/m² (boys) and 20.0 kg/m², 22.5 kg/m² (girls). At equivalent HOMA-IR, SA overweight and obesity thresholds were lower by 2.9 kg/m² (95% CI: 2.5–3.3 kg/m²) and 3.2 kg/m² (95% CI: 2.7–3.6 kg/m²) in boys and 3.0 kg/m² (95% CI: 2.6–3.4 kg/m²) and 3.3 kg/m² (95% CI: 2.8–3.8 kg/m²) in girls, respectively. At these lower thresholds, overweight/obesity prevalences in SA children were approximately doubled (boys: 61%, girls: 56%). Patterns at 10.5 years were similar.

Conclusions

SA adjusted overweight/obesity thresholds based on equivalent IR were markedly lower than BMI thresholds for WE children, and defined more than half of SA children as overweight/obese.

Associations of TV Viewing Duration, Meals and Snacks Eaten When Watching TV, and a TV in the Bedroom with Child Adiposity

OBJECTIVE

This study aimed to examine the associations of TV parameters with adiposity in early life.

METHODS

Data were collected as part of the Born in Bradford (BiB) longitudinal birth cohort study. Child TV viewing duration was parent reported, and BMI, the sum of triceps and subscapular skinfolds, and waist circumference were measured at ~12, 18, 24, and 36 months of age in 1,338 children. Mixed effects models were used to quantify adjusted associations of TV viewing duration with adiposity markers, incorporating data from all time points. Linear regression was used to investigate differences in adiposity levels across frequencies of eating meals and snacks while watching TV at age ~24 months and between children who did and did not have a TV in their bedroom at age ~36 months.

RESULTS

Every 1 h/d of TV viewing was associated with a 0.075-cm larger (95% CI: 0.0034-0.15) waist circumference, independent of covariates including sleep duration, dietary factors, and physical activity level. There was no evidence for any other associations.

CONCLUSIONS

TV viewing duration is independently associated with abdominal adiposity in young children. Limiting TV viewing from an early age may be important for primary prevention of obesity.

Global cities and cultural diversity: challenges and opportunities for young people's nutrition

Childhood obesity is a common concern across global cities and threatens sustainable urban development. Initiatives to improve nutrition and encourage physical exercise are promising but are yet to exert significant influence on prevention. Childhood obesity in London is associated with distinct ethnic and socio-economic patterns. Ethnic inequalities in health-related behaviour endure, underpinned by inequalities in employment, housing, access to welfare services, and discrimination. Addressing these growing concerns requires a clearer understanding of the socio-cultural, environmental and economic contexts of urban living that promote obesity. We explore opportunities for prevention using asset based-approaches to nutritional health and well-being, with a particular focus on adolescents from diverse ethnic backgrounds living in London. We focus on the important role that community engagement and multi-sectoral partnership play in improving the nutritional outcomes of London's children. London's children and adolescents grow up in the rich cultural mix of a global city where local streets are characterised by diversity in ethnicities, languages, religions, foods, and customs, creating complex and fluid identities. Growing up with such everyday diversity we argue can enhance the quality of life for London's children and strengthen their social capital. The Determinants of young Adult Social well-being and Health longitudinal study of about 6500 of London's young people demonstrated the positive impact of cultural diversity. Born to parents from over a hundred countries and exposed to multi-lingual households and religious practices, they demonstrated strong psychological resilience and sense of pride from cultural straddling, despite material disadvantage and discrimination. Supporting the potential contribution of such socio-cultural assets is in keeping with the values of social justice and equitable and sustainable development. Our work signals the importance of community engagement and multisectoral partnerships, involving, for example, schools and faith-based organisations, to improve the nutrition of London's children.

The contribution of physical fitness to individual and ethnic differences in risk markers for type 2 diabetes in children: The Child Heart and Health Study in England (CHASE)

BACKGROUND

The relationship between physical fitness and risk markers for type 2 diabetes (T2D) in children and the contribution to ethnic differences in these risk markers have been little studied. We examined associations between physical fitness and early risk markers for T2D and cardiovascular disease in 9- to 10-year-old UK children.

METHODS

Cross-sectional study of 1445 9- to 10-year-old UK children of South Asian, black African-Caribbean and white European origin. A fasting blood sample was used for measurement of insulin, glucose (from which homeostasis model assessment [HOMA]-insulin resistance [IR] was derived), glycated hemoglobin (HbA1c), urate, C-reactive protein (CRP), and lipids. Measurements of blood pressure (BP) and fat mass index (FMI) were made; physical activity was measured by accelerometry. Estimated VO_{2 max} was derived from a submaximal fitness step test. Associations were estimated using multilevel linear regression.

RESULTS

Higher VO_{2 max} was associated with lower FMI, insulin, HOMA-IR, HbA1c, glucose, urate, CRP, triglycerides, LDL-cholesterol, BP and higher HDL-cholesterol. Associations were reduced by adjustment for FMI, but those for insulin, HOMA-IR, glucose, urate, CRP, triglycerides and BP remained statistically significant. Higher levels of insulin and HOMA-IR in South Asian children were partially explained by lower levels of VO_2max compared to white Europeans, accounting for 11% of the difference.

CONCLUSIONS

Physical fitness is associated with risk markers for T2D and CVD in children, which persist after adjustment for adiposity. Higher levels of IR in South Asians are partially explained by lower physical fitness levels compared to white Europeans. Improving physical fitness may provide scope for reducing risks of T2D.

Stand Out in Class: restructuring the classroom environment to reduce sedentary behaviour in 9-10-year-olds - study protocol for a pilot cluster randomised controlled trial

Background

Sedentary behaviour (sitting) is a highly prevalent negative health behaviour, with individuals of all ages exposed to environments that promote prolonged sitting. Excessive sedentary behaviour adversely affects health in children and adults. As sedentary behaviour tracks from childhood into adulthood, the reduction of sedentary time in young people is key for the prevention of chronic diseases that result from excessive sitting in later life. The sedentary school classroom represents an ideal setting for environmental change, through the provision of sit-stand desks. Whilst the use of sit-stand desks in classrooms demonstrates positive effects in some key outcomes, evidence is currently limited by small samples and/or short intervention durations, with few studies adopting randomised controlled trial (RCT) designs. This paper describes the protocol of a pilot cluster RCT of a sit-stand desk intervention in primary school classrooms.

Methods/Design

A two-arm pilot cluster RCT will be conducted in eight primary schools (four intervention, four control) with at least 120 year 5 children (aged 9-10 years). Sit-stand desks will replace six standard desks in the intervention classrooms. Teachers will be encouraged to ensure all pupils are exposed to the sit-stand desks for at least 1 h/day on average using a rotation system. Schools assigned to the control arm will continue with their usual practice, no environmental changes will be made to their classrooms. Measurements will be taken at baseline, before randomisation, and at the end of the schools' academic year. In this study, the primary outcomes of interest will be school and participant recruitment and attrition, acceptability of the intervention, and acceptability and compliance to the proposed outcome measures (including activPAL-measured school-time and school-day sitting, accelerometer-measured physical activity, adiposity, blood pressure, cognitive function, academic progress, engagement, and behaviour) for inclusion in a definitive trial. A full process evaluation and an exploratory economic evaluation will also be conducted to further inform a definitive trial.

Discussion

The primary output of this study will be acceptability data to inform the development of a definitive cluster RCT designed to examine the efficacy of this intervention on health- and education-related outcomes in UK primary school children.

Trial registration

ISRCTN12915848 (retrospectively registered, date registered 9 November 2016).

Takeaway meal consumption and risk markers for coronary heart disease, type 2 diabetes and obesity in children aged 9-10 years: a cross-sectional study

OBJECTIVE

To investigate associations between takeaway meal consumption and risk markers for coronary heart disease, type 2 diabetes and obesity risk markers in children.

DESIGN

A cross-sectional, school-based observational study.

SETTING

85 primary schools across London, Birmingham and Leicester.

PARTICIPANTS

1948 UK primary school children in year 5, aged 9-10 years.

MAIN OUTCOME MEASURES

Children reported their frequency of takeaway meal consumption, completed a 24-hour dietary recall, had physical measurements and provided a fasting blood sample.

RESULTS

Among 1948 participants with complete data, 499 (26%) never/hardly ever consumed a takeaway meal, 894 (46%) did so <1/week and 555 (28%) did ≥1/week. In models adjusted for age, sex, month, school, ethnicity and socioeconomic status, more frequent takeaway meal consumption was associated with higher dietary intakes of energy, fat % energy and saturated fat % energy and higher energy density (all P trend <0.001) and lower starch, protein and micronutrient intakes (all P trend <0.05). A higher frequency of takeaway meal consumption was associated with higher serum total cholesterol and low-density lipoprotein (LDL) cholesterol (P trend=0.04, 0.01, respectively); children eating a takeaway meal ≥1/week had total cholesterol and LDL cholesterol 0.09 mmol/L (95% CI 0.01 to 0.18) and 0.10 mmol/L (95% CI 0.02 to 0.18) higher respectively than children never/hardly ever eating a takeaway meal; their fat mass index was also higher.

CONCLUSIONS

More frequent takeaway meal consumption in children was associated with unhealthy dietary nutrient intake patterns and potentially with adverse longer term consequences for obesity and coronary heart disease risk.

BMI-for-age in South Asian children of 0-20 years in the Netherlands: secular changes and misclassification by WHO growth references

BACKGROUND

South Asians are prone to cardiometabolic disease at lower BMI levels than most other ethnic groups, starting in childhood. The magnitude of BMI misclassifications is unknown.

AIM

To compare the BMI distribution of contemporary South Asian 0-20 year olds in the Netherlands with: (1) The South Asian norm reference (secular trends); and (2) The WHO child growth standard and reference.

SUBJECTS AND METHODS

The BMI-for-age distribution of 6677 routine measurements of 3322 South Asian children, aged 0-20 years, was described with the LMS method and BMI z-scores.

RESULTS

The BMI distribution in South Asian 0-4 year olds was almost similar to the norm reference (mean BMI z-score = 0.11, skewness = 0.31, SD = 1.0), whereas in 5-19 year olds the distribution had shifted upwards (mean = 0.53) and widened (skewness = -0.12, SD = 1.08). Overweight (incl. obesity) and obesity peaked at 8-10 years, at 45-48% and 35-37%, respectively. Relative to the WHO references, the BMI distribution was left-shifted at ages 0-4 years (mean BMI z-score = -0.46, skewness = 0.23, SD = 0.98) and widened at ages 5-20 years (mean = 0.05; skewness = -0.02, SD = 1.40). At most ages, thinness rates were significantly higher and obesity rates lower than based on South Asian norms.

CONCLUSIONS

A secular change of BMI-for-age in South Asian children mostly affected children >4 years. WHO references likely under-estimate overweight and obesity rates in South Asian children.

Reassessing Ethnic Differences in Mean BMI and Changes Between 2007 and 2013 in English Children

OBJECTIVE

National body fatness (BF) data for English South Asian and Black children use BMI, which provides inaccurate ethnic comparisons. BF levels and time trends in the English National Child Measurement Programme (NCMP) between 2007 and 2013 were assessed by using ethnic-specific adjusted BMI (aBMI) for South Asian and Black children.

METHODS

Analyses were based on 3,195,323 children aged 4 to 5 years and 2,962,673 children aged 10 to 11 years. aBMI values for South Asian and Black children (relating to BF as in White children) were derived independently. Mean aBMI levels and 5-year aBMI changes were obtained by using linear regression.

RESULTS

In the 2007-2008 NCMP, mean aBMIs in 10- to 11-year-old children (boys, girls) were higher in South Asian children (20.1, 19.9 kg/m² ) and Black girls, but not in Black boys (18.4, 19.2 kg/m² ) when compared with White children (18.6, 19.0 kg/m² ; all P < 0.001). Mean 5-year changes (boys, girls) were higher in South Asian children (0.16, 0.32 kg/m² per 5 y; both P < 0.001) and Black boys but not girls (0.13, 0.15 kg/m² per 5 y; P = 0.01, P = 0.41) compared with White children (0.02, 0.11 kg/m² per 5 y). Ethnic differences at 4 to 5 years were similar. Unadjusted BMI showed similar 5-year changes but different mean BMI patterns.

CONCLUSIONS

BF levels were higher in South Asian children than in other groups in 2007 and diverged from those in White children until 2013, a pattern not apparent from unadjusted BMI data.

Patterns of childhood body mass index (BMI), overweight and obesity in South Asian and black participants in the English National child measurement programme: effect of applying BMI adjustments standardising for ethnic differences in BMI-body fatness associations

Background:

The National Child Measurement Programme (NCMP) records weight and height and assesses overweight-obesity patterns in English children using body mass index (BMI), which tends to underestimate body fatness in South Asian children and overestimate body fatness in Black children of presumed African ethnicity. Using BMI adjustments to ensure that adjusted BMI was similarly related to body fatness in South Asian, Black and White children, we reassessed population overweight and obesity patterns in these ethnic groups in NCMP.

Methods:

Analyses were based on 2012–2013 NCMP data in 582 899 children aged 4–5 years and 485 362 children aged 10–11 years. Standard centile-based approaches defined weight status in each age group before and after applying BMI adjustments for English South Asian and Black children derived from previous studies using the deuterium dilution method.

Findings:

Among White children, overweight-obesity prevalences (boys, girls) were 23% and 21%, respectively, in 4–5 year olds and 33% and 30%, respectively, in 10–11 year olds. Before adjustment, South Asian children had lower overweight-obesity prevalences at 4–5 years (19%, 19%) and slightly higher prevalences at 10–11 years (42%, 34%), whereas Black children had higher overweight-obesity prevalences both at 4–5 years (31%, 29%) and 10–11 years (42%, 45%). Following adjustment, overweight-obesity prevalences were markedly higher in South Asian children both at 4–5 years (39%, 35%) and at 10–11 years (52%, 44%), whereas Black children had lower prevalences at 4–5 years (11%, 12%); at 10–11 years, prevalences were slightly lower in boys (32%) but higher in girls (35%).

Interpretation:

BMI adjustments revealed extremely high overweight-obesity prevalences among South Asian children in England, which were not apparent in unadjusted data. In contrast, after adjustment, Black children had lower overweight-obesity prevalences except among older girls.

Funding:

British Heart Foundation, NIHR CLAHRC (South London), NIHR CLAHRC (North Thames).

Asian Adolescents with Excess Weight are at Higher Risk for Insulin Resistance than Non-Asian Peers

OBJECTIVE

The purpose of this study was to evaluate whether Asian American adolescents have higher metabolic risk from excess weight than non-Asians.

METHODS

Seven hundred thirty-three students, aged 14 to 19 years old, completed a school-based health screening. The 427 Asian and 306 non-Asian students were overall equivalent on age, sex, and family income. Height, weight, waist circumference, percent body fat, and blood pressure were measured. Fasting triglycerides, high- and low-density lipoproteins, glucose, and insulin levels were measured. Asian and non-Asians in lean or overweight/obesity groups were contrasted on the five factors that make up the metabolic syndrome.

RESULTS

Asian adolescents carrying excess weight had significantly higher insulin resistance (IR), triglyceride levels, and waist-height ratios (W/H), despite a significantly lower overall BMI than corresponding non-Asians. Similarly, Asians had a stronger relationship between W/H and the degree of IR than non-Asian counterparts; 35% and 18% of the variances were explained (R² = 0.35, R² = 0.18) respectively, resulting in a significant W/H by racial group interaction (F_change [1,236] = 11.56, P < 0.01).

CONCLUSIONS

Despite lower overall BMI, Asians have higher IR and triglyceride levels from excess weight than their non-Asian counterparts. One-size-fits-all public health policies targeting youth should be reconsidered and attention paid to Asian adolescents, including those with mild degrees of excess weight.

Sleep Duration and Adiposity in Early Childhood: Evidence for Bidirectional Associations from the Born in Bradford Study

Study Objectives:

To examine independent associations of sleep duration with total and abdominal adiposity, and the bidirectionality of these associations, in a young biethnic sample of children from a disadvantaged location.

Methods:

Child sleep duration (h/day) was parent-reported by questionnaire and indices of total (body weight, body mass index, percent body fat (%BF), sum of skinfolds) and abdominal adiposity (waist circumference) were measured using standard anthropometric procedures at approximately 12, 18, 24, and 36 months of age in 1,338 children (58% South Asian; 42% White). Mixed effects models were used to quantify independent associations (expressed as standardised β-coefficients (95% confidence interval (CI)) of sleep duration with adiposity indices using data from all four time-points. Factors considered for adjustment in models included basic demographics, pregnancy and birth characteristics, and lifestyle behaviours.

Results:

With the exception of the sum of skinfolds, sleep duration was inversely and independently associated with indices of total and abdominal adiposity in South Asian children. For example, one standard deviation (SD) higher sleep duration was associated with reduced %BF by -0.029 (95% CI: −0.053, −0.0043) SDs. Higher adiposity was also independently associated with shorter sleep duration in South Asian children (for example, %BF: β = -0.10 (-0.16, -0.028) SDs). There were no significant associations in White children.

Conclusions:

Associations between sleep duration and adiposity are bidirectional and independent among South Asian children from a disadvantaged location. The results highlight the importance of considering adiposity as both a determinant of decreased sleep and a potential consequence.

Sleep Duration and Risk of Type 2 Diabetes

BACKGROUND

Associations between sleep duration and type 2 diabetes (T2D) risk markers in childhood have been little studied. We examined associations between self-reported sleep duration and T2D risk markers in children.

METHODS

Cross-sectional study of 4525 multiethnic UK children aged 9 to 10 years. Sleep time was calculated from self-reported usual time of going to bed and getting up on a school day, validated in a subset using accelerometers. Fasting blood samples provided levels of serum lipids and insulin, plasma glucose, and HbA1c. Physical measures included height, weight, bioimpedance, and blood pressure. Multilevel linear regression models of anthropometric, T2D, and cardiovascular risk markers with sleep duration were adjusted for sex, age, month, ethnicity, socioeconomic position, observer (physical measures only), and random effect of school.

RESULTS

On average, children slept 10.5 hours per night (95% range 8.0-12.0 hours). There were strong inverse graded relationships between sleep duration, adiposity, and diabetes risk markers. In adjusted models, a 1-hour-longer sleep duration was associated with 0.19 lower BMI (95% confidence interval [CI] 0.09 to 0.28), 0.03 kg/m⁵ lower fat mass index (95% CI 0.00 to 0.05 kg/m⁵), 2.9% lower homeostasis model assessment insulin resistance (95% CI 1.2% to 4.4%), and 0.24% lower fasting glucose (95% CI 0.03% to 0.44%); there was no association with HbA1c or cardiovascular risk. Associations with insulin and glucose remained after an additional adjustment for adiposity markers.

CONCLUSIONS

The finding of an inverse association between sleep duration and T2D risk markers in childhood is novel. Intervention studies are needed to establish the causality of these associations, which could provide a simple strategy for early T2D prevention.

Screen time is associated with adiposity and insulin resistance in children

BACKGROUND

Higher screen time is associated with type 2 diabetes (T2D) risk in adults, but the association with T2D risk markers in children is unclear. We examined associations between self-reported screen time and T2D risk markers in children.

METHODS

Survey of 4495 children aged 9-10 years who had fasting cardiometabolic risk marker assessments, anthropometry measurements and reported daily screen time; objective physical activity was measured in a subset of 2031 children.

RESULTS

Compared with an hour or less screen time daily, those reporting screen time over 3 hours had higher ponderal index (1.9%, 95% CI 0.5% to 3.4%), skinfold thickness (4.5%, 0.2% to 8.8%), fat mass index (3.3%, 0.0% to 6.7%), leptin (9.2%, 1.1% to 18.0%) and insulin resistance (10.5%, 4.9% to 16.4%); associations with glucose, HbA1c, physical activity and cardiovascular risk markers were weak or absent. Associations with insulin resistance remained after adjustment for adiposity, socioeconomic markers and physical activity.

CONCLUSIONS

Strong graded associations between screen time, adiposity and insulin resistance suggest that reducing screen time could facilitate early T2D prevention. While these observations are of considerable public health interest, evidence from randomised controlled trials is needed to suggest causality.

Body mass index adjustments to increase the validity of body fatness assessment in UK Black African and South Asian children

Background/Objectives:

Body mass index (BMI) (weight per height²) is the most widely used marker of childhood obesity and total body fatness (BF). However, its validity is limited, especially in children of South Asian and Black African origins. We aimed to quantify BMI adjustments needed for UK children of Black African and South Asian origins so that adjusted BMI related to BF in the same way as for White European children.

Methods:

We used data from four recent UK studies that made deuterium dilution BF measurements in UK children of White European, South Asian and Black African origins. A height-standardized fat mass index (FMI) was derived to represent BF. Linear regression models were then fitted, separately for boys and girls, to quantify ethnic differences in BMI–FMI relationships and to provide ethnic-specific BMI adjustments.

Results:

We restricted analyses to 4–12 year olds, to whom a single consistent FMI (fat mass per height⁵) could be applied. BMI consistently underestimated BF in South Asians, requiring positive BMI adjustments of +1.12 kg m⁻² (95% confidence interval (CI): 0.83, 1.41 kg m⁻²; P<0.0001) for boys and +1.07 kg m⁻² (95% CI: 0.74, 1.39 kg m⁻²; P<0.0001) for girls of all age groups and FMI levels. BMI overestimated BF in Black Africans, requiring negative BMI adjustments for Black African children. However, these were complex because there were statistically significant interactions between Black African ethnicity and FMI (P=0.004 boys; P=0.003 girls) and also between FMI and age group (P<0.0001 for boys and girls). BMI adjustments therefore varied by age group and FMI level (and indirectly BMI); the largest adjustments were in younger children with higher unadjusted BMI and the smallest in older children with lower unadjusted BMI.

Conclusions:

BMI underestimated BF in South Asians and overestimated BF in Black Africans. Ethnic-specific adjustments, increasing BMI in South Asians and reducing BMI in Black Africans, can improve the accuracy of BF assessment in these children.

Are Ethnic Disparities in HbA1c Levels Explained by Mental Wellbeing? Analysis of Population-Based Data from the Health Survey for England

Aims

It is unclear how ethnic differences in HbA_1c levels are affected by individual variations in mental wellbeing. Thus, the aim of this study was to assess the extent to which HbA_1c disparities between Caucasian and South Asian adults are mediated by various aspects of positive psychological functioning.

Methods

Data from the 2014 Health Survey for England was analysed using bootstrapping methods. A total of 3894 UK residents with HbA_1c data were eligible to participate. Mental wellbeing was assessed using the Warwick-Edinburgh Mental Well-being Scale. To reduce bias BMI, blood pressure, diabetes status, and other factors were treated as covariates.

Results

Ethnicity directly predicted blood sugar control (unadjusted coefficient −2.15; 95% CI −3.64, −0.67), with Caucasians generating lower average HbA_1c levels (37.68 mmol/mol (5.6%)) compared to South Asians (39.87 mmol/mol (5.8%)). This association was mediated by positive mental wellbeing, specifically concerning perceived vigour (unadjusted effect 0.30; 95% CI 0.13, 0.58): South Asians felt more energetic than Caucasians (unadjusted coefficient −0.32; 95% CI −0.49, −0.16), and greater perceived energy predicted lower HbA_1c levels (unadjusted coefficient −0.92; 95% CI −1.29, −0.55). This mediator effect accounted for just over 14% of the HbA_1c variance and was negated after adjusting for BMI.

Conclusions

Caucasian experience better HbA_1c levels compared with their South Asian counterparts. However, this association is partly confounded by individual differences in perceived energy levels, which is implicated in better glycaemic control, and appears to serve a protective function in South Asians.

Young, healthy South Asians have enhanced lipogenic sensitivity to dietary sugar

OBJECTIVE

South Asians have higher rates of type 2 diabetes and cardiovascular disease compared to most other racial/ethnic groups. Increased hepatic de novo lipogenesis (DNL) in response to dietary sugar may accelerate the development of these chronic diseases in this population.

STUDY DESIGN

Hepatic DNL in response to a calorically sweetened beverage was measured in an outpatient setting in 15 South Asians and 15 Caucasians with similar and normal body mass indexes, waist circumferences, glucose tolerance and lipid profiles. Blood was sampled before and hourly for 4 h after the ingestion of a single beverage made with glucose (1·5 g/kg) and fructose (1·5 g/kg). The main outcome, DNL, was measured as the increase in %palmitate (16:0) in very low-density lipoprotein (VLDL) triglyceride (TG) over 4 h.

RESULTS

After the sugar dose, the increase in %16:0 in VLDL TG was significantly greater in South Asians vs Caucasians (P = 0·01). VLDL and total TG also increased to a significantly greater extent in South Asians (P = 0·04 and <0·001, respectively). Although the fasting and postsugar levels of insulin and glucose did not differ between groups, the DNL response significantly correlated with the insulin response to sugar in South Asians (r = 0·56, P = 0·03).

CONCLUSIONS

Hepatic DNL in response to a sugar challenge was greater in healthy, young South Asians compared to Caucasians despite normal indices of insulin sensitivity, and it correlated with the insulin response. These findings suggest an early, insulin-related, gene-nutrient interaction contributing to the high prevalence of diabetes and coronary disease in this population.