Oarabile R. Molaodi

Neighbourhood food and physical activity environments in England, UK: does ethnic density matter?

BackgroundIn England, obesity is more common in some ethnic minority groups than in Whites. This study examines the relationship between ethnic concentration and access to fast food outlets, supermarkets and physical activity facilities.MethodsData on ethnic concentration, fast food outlets, supermarkets and physical activity facilities were obtained at the lower super output area (LSOA) (population average of 1500). Poisson multilevel modelling was used to examine the association between own ethnic concentration and facilities, adjusted for area deprivation, urbanicity, population size and clustering of LSOAs within local authority areas.ResultsThere was a higher proportion of ethnic minorities residing in areas classified as most deprived. Fast food outlets and supermarkets were more common and outdoor physical activity facilities were less common in most than least deprived areas. A gradient was not observed for the relationship between indoor physical activity facilities and area deprivation quintiles. In contrast to White British, increasing ethnic minority concentration was associated with increasing rates of fast food outlets. Rate ratios comparing rates of fast food outlets in high with those in low level of ethnic concentration ranged between 1.28, 95% confidence interval 1.06-1.55 (Bangladeshi) and 2.62, 1.46-4.70 (Chinese). Similar to White British, however, increasing ethnic minority concentration was associated with increasing rate of supermarkets and indoor physical activity facilities. Outdoor physical activity facilities were less likely to be in high than low ethnic concentration areas for some minority groups.ConclusionsOverall, ethnic minority concentration was associated with a mixture of both advantages and disadvantages in the provision of food outlets and physical activity facilities. These issues might contribute to ethnic differences in food choices and engagement in physical activity.

Effect of air pollution and racism on ethnic differences in respiratory health among adolescents living in an urban environment

Recent studies suggest that stress can amplify the harm of air pollution. We examined whether experience of racism and exposure to particulate matter with an aerodynamic diameter of less than 2.5 µm and 10 µm (PM2.5 and PM10) had a synergistic influence on ethnic differences in asthma and lung function across adolescence. Analyses using multilevel models showed lower forced expiratory volume (FEV1), forced vital capacity (FVC) and lower rates of asthma among some ethnic minorities compared to Whites, but higher exposure to PM2.5, PM10 and racism. Racism appeared to amplify the relationship between asthma and air pollution for all ethnic groups, but did not explain ethnic differences in respiratory health.

Ethnic differences in and childhood influences on early adult pulse wave velocity: The determinants of adolescent, now young adult, social wellbeing, and health longitudinal study

Early determinants of aortic stiffness as pulse wave velocity are poorly understood. We tested how factors measured twice previously in childhood in a multiethnic cohort study, particularly body mass, blood pressure, and objectively assessed physical activity affected aortic stiffness in young adults. Of 6643 London children, aged 11 to 13 years, from 51 schools in samples stratified by 6 ethnic groups with different cardiovascular risk, 4785 (72%) were seen again at aged 14 to 16 years. In 2013, 666 (97% of invited) took part in a young adult (21–23 years) pilot follow-up. With psychosocial and anthropometric measures, aortic stiffness and blood pressure were recorded via an upper arm calibrated Arteriograph device. In a subsample (n=334), physical activity was measured >5 days via the ActivPal. Unadjusted pulse wave velocities in black Caribbean and white UK young men were similar (mean±SD 7.9±0.3 versus 7.6±0.4 m/s) and lower in other groups at similar systolic pressures (120 mm Hg) and body mass (24.6 kg/m2). In fully adjusted regression models, independent of pressure effects, black Caribbean (higher body mass/waists), black African, and Indian young women had lower stiffness (by 0.5–0.8; 95% confidence interval, 0.1–1.1 m/s) than did white British women (6.9±0.2 m/s). Values were separately increased by age, pressure, powerful impacts from waist/height, time spent sedentary, and a reported racism effect (+0.3 m/s). Time walking at >100 steps/min was associated with reduced stiffness (P<0.01). Effects of childhood waist/hip were detected. By young adulthood, increased waist/height ratios, lower physical activity, blood pressure, and psychosocial variables (eg, perceived racism) independently increase arterial stiffness, effects likely to increase with age.

Can arterial wave augmentation in young adults help account for variability of cardiovascular risk in different British ethnic groups

Objective: Traditional cardiovascular risk factors do not fully account for ethnic differences in cardiovascular disease. We tested if arterial function indices, particularly augmentation index (AIx), and their determinants from childhood could underlie such ethnic variability among young British adults in the ‘DASH’ longitudinal study. Methods: DASH, at http://dash.sphsu.mrc.ac.uk/, includes representative samples of six main British ethnic groups. Pulse wave velocity (PWV) and AIx were recorded using the Arteriograph device at ages 21–23 years in a subsample (n = 666); psychosocial, anthropometric, and blood pressure (BP) measures were collected then and in two previous surveys at ages 11–13 years and 14–16 years. For n = 334, physical activity was measured over 5 days (ActivPal). Results: Unadjusted values and regression models for PWVs were similar or lower in ethnic minority than in White UK young adults, whereas AIx was higher – Caribbean (14.9, 95% confidence interval 12.3–17.0%), West African (15.3, 12.9–17.7%), Indian (15.1, 13.0–17.2%), and Pakistani/Bangladeshi (15.7, 13.7–17.7%), compared with White UK (11.9, 10.2–13.6%). In multivariate models, adjusted for sex, central SBP, height, and heart rate, Indian and Pakistani/Bangladeshi young adults had higher AIx (&bgr; = 3.35, 4.20, respectively, P < 0.01) than White UK with a similar trend for West Africans and Caribbeans but not statistically significant. Unlike PWV, physical activity, psychosocial or deprivation measures were not associated with AIx, with borderline associations from brachial BP but no other childhood variables. Conclusion: Early adult AIx, but not arterial stiffness, may be a useful tool for testing components of excess cardiovascular risk in some ethnic minority groups.

Longitudinal study of cardiometabolic risk from early adolescence to early adulthood in an ethnically diverse cohort

Objective To examine influences of adiposity from early adolescence to early 20s on cardiovascular disease (CVD) risk in the multiethnic Determinants of young Adult Social well-being and Health (DASH) longitudinal study. Methods In 2002–2003, 6643 11–13-year-olds from 51 London schools participated at baseline, and 4785 were seen again at 14–16 years. Recently, 665 (97% of invited) participated in pilot follow-up at 21–23 years, with biological and psychosocial measures and blood biomarkers (only at 21–23 years). Regression models examined interplay between ethnicity, adiposity and CVD. Results At 21–23 years, ∼30–40% were overweight. About half of the sample had completed a degree with little ethnic variation despite more socioeconomic disadvantage in adolescence among ethnic minorities. Regardless of ethnicity, overweight increased more steeply between 14–16 years and 21–23 years than between 11–13 years and 14–16 years. More overweight among Black Caribbean and Black African females, lower systolic blood pressure (sBP) among Indian females and Pakistani/Bangladeshi males compared with White UK peers, persisted from 11–13 years. At 21–23 years, glycated haemoglobin (HbA1c) was higher among Black Caribbean females, total cholesterol higher and high-density lipoprotein (HDL) cholesterol lower among Pakistani/Bangladeshis. Overweight was associated with a ∼+2 mm Hg rise in sBP between 11–13 years and 21–23 years. Adiposity measures at 11–13 years were related to allostatic load (a cluster of several risk markers), HbA1c and HDL cholesterol at 21–23 years. Ethnic patterns in CVD biomarkers remained after adjustments. Conclusions Adolescent adiposity posed significant risks at 21–23 years, a period in the lifespan generally ignored in cardiovascular studies, when ethnic/gender variations in CVD are already apparent.

Birth weight and maternal socioeconomic circumstances were inversely related to systolic blood pressure among Afro-Caribbean young adults

OBJECTIVES In this study, we examined the effects of birth weight (BWT) and early life socioeconomic circumstances (SEC) on systolic blood pressure (SBP) and diastolic blood pressure (DBP) among Jamaican young adults. STUDY DESIGN AND SETTING Longitudinal study of 364 men and 430 women from the Jamaica 1986 Birth Cohort Study. Information on BWT and maternal SEC at childs birth was linked to information collected at 18-20 years old. Sex-specific multilevel linear regression models were used to examine whether adult SBP/DBP was associated with BWT and maternal SEC. RESULTS In unadjusted models, SBP was inversely related to BWT z-score in both men (β, -0.82 mm Hg) and women (β, -1.18 mm Hg) but achieved statistical significance for women only. In the fully adjusted model, one standard deviation increase in BWT was associated with 1.16 mm Hg reduction in SBP among men [95% confidence interval (CI): 2.15, 0.17; P = 0.021] and 1.34 mm Hg reduction in SBP among women (95% CI: 2.21, 0.47; P = 0.003). Participants whose mothers had lower SEC had higher SBP compared with those with mothers of high SEC (β, 3.4-4.8 mm Hg for men, P < 0.05 for all SEC categories and 1.8-2.1 for women, P > 0.05). CONCLUSION SBP was inversely related to maternal SEC and BWT among Jamaican young adults.

Effects of restrictions to Income Support on health of lone mothers in the UK: a natural experiment study

Summary Background In the UK, lone parents must seek work as a condition of receiving welfare benefits once their youngest child reaches a certain age. Since 2008, the lower age limit at which these Lone Parent Obligations (LPO) apply has been reduced in steps. We used data from a nationally representative, longitudinal, household panel study to analyse the health effects of increased welfare conditionality under LPO. Methods From the Understanding Society survey, we used data for lone mothers who were newly exposed to LPO when the age cutoff was reduced from 7 to 5 years in 2012 (intervention group 1) and from 10 to 7 years in 2010 (intervention group 2), as well as lone mothers who remained unexposed (control group 1) or continuously exposed (control group 2) at those times. We did difference-in-difference analyses that controlled for differences in the fixed characteristics of participants in the intervention and control groups to estimate the effect of exposure to conditionality on the health of lone mothers. Our primary outcome was the difference in change over time between the intervention and control groups in scores on the Mental Component Summary (MCS) of the 12-item Short-Form Health Survey (SF-12). Findings The mental health of lone mothers declined in the intervention groups compared with the control groups. For intervention group 1, scores on the MCS decreased by 1·39 (95% CI −1·29 to 4·08) compared with control group 1 and by 2·29 (0·00 to 4·57) compared with control group 2. For intervention group 2, MCS scores decreased by 2·45 (−0·57 to 5·48) compared with control group 1 and by 1·28 (−1·45 to 4·00) compared with control group 2. When pooling the two intervention groups, scores on the MCS decreased by 2·13 (0·10 to 4·17) compared with control group 1 and 2·21 (0·30 to 4·13) compared with control group 2. Interpretation Stringent conditions for receiving welfare benefits are increasingly common in high-income countries. Our results suggest that requiring lone parents with school-age children toseek work as a condition of receiving welfare benefits adversely affects their mental health. Funding UK Medical Research Council, Scottish Government Chief Scientist Office, and National Health Service Research Scotland.

Longitudinal study of the influence of lung function on vascular health from adolescence to early adulthood in a British multiethnic cohort

Background: Vascular and lung function develop and decline over the life course; both predict cardiovascular events and mortality but little is known of how they develop over time. We analysed their relationship in a multiethnic cohort study to test whether lung function from early adolescence to young adulthood affected vascular indices. Methods: ‘DASH’ (http://dash.sphsu.mrc.ac.uk) included 6643 children aged 11–13 years in 2003; a representative 10% sample (n = 665) participated in a pilot follow-up in 2013. Psychosocial, anthropometric, blood pressure (BP), and lung function measures were collected in both surveys; aortic pulse wave velocity (PWV) and augmentation index (AIx) were measured at aged 21–23 years. Relationships between forced expiratory volume Z-scores in 1 s (zFEV1), after global initiative-ethnic adjustments and BP, PWV, and AIx were tested in linear regression and general estimating statistical models. Results: In total, 488 people with complete data were included. At 11–13 years, SBP was positively associated with zFEV1 (coefficient = 1.90, 95% confidence interval 1.11–2.68, P < 0.001); but not at 21–23 years. The 10-year increase in zFEV1 was associated with rise in SBP (1.38, 0.25–1.51, P < 0.05) in mixed effect models adjusted for age, sex, ethnicity, waist to height ratio, employment, reported racism, smoking, and alcohol use but DBP change was unrelated. In fully adjusted models, neither PWV nor central AIx were associated with zFEV1 at 11–13 years or 21–23 years (P > 0.05). Conclusion: Forced expiratory volume change is positively and independently associated with SBP change from adolescence to young adulthood, suggesting earlier lung function plays important roles in SBP development. Vascular indices were unrelated to lung function or its change.

Associations of Blood Pressure with Body Composition among Afro-Caribbean Children in Barbados

Despite complex presentation of adult hypertension and a concomitant obesity epidemic, little is known about overweight in relation to blood pressure among Caribbean children. We examined blood pressure in relation to body size in a cross-sectional study of 573 Barbadian children aged 9–10 years (2010-2011).The United States normative blood pressure percentiles were used to identify children with high (≥ 95th percentile) or high normal blood pressure (90th – 95th percentile). The World Health Organization body mass index cut-off points were used to assess weight status. Major findings Thirty percent of children were overweight/obese. Percentage fat mass differed between girls (20.4%) and boys (17.72%) (p< 0.05). Mean systolic blood pressure among girls was 106.11 (95% CI 105.05, 107.17) mmHg and 105.23 (104.09, 106.38) for boys. The percentages with high or high-normal mean systolic blood pressurewere14.38% (10.47, 18.29) for girls and 8.08% (4.74, 11.41) for boys. Height and body mass index were independent correlates of systolic and diastolic blood pressure. Mean systolic blood pressure was related to lean mass but not fat mass, while diastolic blood pressure was associated with fat mass index and overweight. Principal conclusion One third of 9-10 year old children in Barbados were overweight/obese and 12% had elevated mean systolic blood pressure. BP was related to body size. These findings signal potential adverse trends in weight gain and BP trends for children growing up in the context of a country that has recently undergone rapid economic transition.

The effect of flexible settings on participation rates, data quality, and costs in a longitudinal study of ethnically diverse young adults: the London Determinants of young Adult Social wellbeing and Health (DASH) study

Abstract Background The loss of young and disadvantaged people in cohort studies compromises representativeness and scientific and public value. The Determinants of young Adult Social wellbeing and Health (DASH) study is a longitudinal study of young people in London, mainly from ethnic minorities, and has a social epidemiological focus. The cohort is now aged 21–23 years, an important transition phase to adulthood that influences health and wellbeing in later life. We examine the costs and benefits of different settings on motivation for participation. Methods 6643 11–13-year-olds from 51 London schools took part in the baseline survey in 2002–03 and 4781 were seen again at age 14–16 years. So far, 81% (5414 of 6643) of the cohort has been traced through friendship networks, social media, and community campaigns. A feasibility study of best practice for full follow-up was done with 400 participants between June, 2012, and August, 2013, the design of which was informed by systematic reviews. A sample of about 50 people per ethnic group (Indian, Pakistani, Bangladeshi, black Africans, black Caribbeans, white British) was chosen to give a reasonable spread by sex and socioeconomic position and across all boroughs and schools. Flexibility in settings was based on number of interview locations available (least, two; intermediate, three; most, six) and appointment times (weekdays 0900–1700 h, other). Interview locations were general practice surgeries and community pharmacies within 2 km of residential postcodes; Muslims living in east London were offered the choice of a Clinical Research Centre close to a large mosque; and central locations (Clinical Research Facility at University College Hospital and Kings College London). Participants were given GB£25 shopping vouchers and £30 vouchers if they needed childcare, and reimbursed travel expenses. A main questionnaire covered topics such as socioeconomic circumstances, social support, racism, own and parental health, and health behaviours. Dietary intake over the past 24 h was obtained in a recall questionnaire. Physical measures were done and a blood sample was also taken. The primary outcome was participation rate. Secondary outcomes were cost per participant (CPP) and quality of data. A combination of our own study team and surgery nurses was used. Interviewers were trained for 3 days and compliance to protocol was assessed by regular shadowing and analysis of data by interviewer identification code. Findings 97% (400 of 413) of those invited took part. Participation increased with flexibility in choice of interview locations (least 15%, 95% CI 11–19; intermediate 27%, 23–32; most 58%, 53–63) and was substantially boosted by weekend and evening appointments (weekday 0900–1700 h 76%, 71–80; other 24%, 17–30). CPP varied by setting from £229 (95% CI 220–239; Kings College London, 179 participants seen by study team) to £283 (276–289; Clinical Research Facility, 22 seen by their nurses). Compliance to the protocol and the quality measures were high across settings (p>0·05 for 11 of 13 measures). The CPP for those seen (40 participants) by surgery nurses was intermediate at £240 (95% CI 225–255), but the quality measures were least favourable (eg, consent for bloods 82·5%, 95% CI 70·2–94·8 vs 96·0%, 92·7–99·2 for Kings College London). Compliance to protocol was compromised by very busy environments of inner-city surgeries in deprived areas and limited familiarity with population cohorts. Interpretation Flexibility in interview locations and appointment times boosted participation rates. The use of our own study team rather than surgery nurses was associated with lower CPP and better quality data. Participants were not randomly assigned to a setting, which comprised comparisons of setting-specific participation rates. Funding The DASH study is funded by the UK Medical Research Council (MC_U130015185/MC_UU_12017/1) North Central London Research Consortium, Primary Care Research Network.