Social determinants of diabetes, hypertension, stroke, and coronary heart disease in Black Caribbean and Black African women aged 40 years or older in south London: findings from 70 582 primary care records from 2000–18

Abstract

BackgroundThe contribution of social determinants, such as deprivation and health-related behaviours, to Black African and Black Caribbean–White differences in cardiovascular risks is uncertain. MethodsPrimary care records from 44 practices in Lambeth (Lambeth DataNet) from Jan 1, 2000, to Oct 27, 2018, for women aged 40 years or older were analysed using multilevel logistic regression models adjusted for age, income deprivation, lifestyles, health-care access, comorbidities (Quality and Outcome Framework disease registers) and medications, and for clustering of patients within practices. FindingsWe studied 70 582 women aged 40 years or older from White (n=35 297), Black African (n=11 206), and Black Caribbean (n=9193) ethnic groups. In women aged 40–69 years, smoking levels were similar in White and Black Caribbean groups (approximately 19%), but much lower in Black African groups (6·1%). In both age groups, obesity levels (ie, a body-mass index of ≥30 kg/m2) in Black Caribbean women (44·3%) and Black African women (48·9%) were around double that in White women (20·8%). Levels of missing data were low (2–10%), and were included as a separate category in each variable. Adjusted for age and income deprivation and compared with White women, excess risks observed at age 40–69 years (n=59 132) for Black African women were diabetes (odds ratio [OR] 2·94, 95% CI 2·69–3·20; p<0·0001), hypertension (3·80, 3·56–4·05; p<0·0001), and stroke (1·43, 1·11–1·85; p=0·006), and for Black Caribbean women were diabetes (3·10, 2·84–3·39; p<0·0001), hypertension (3·57, 3·34–3·82; p<0·0001), and stroke (1·53, 1·17–1·99; p=0·002). In women aged 70 years and older (n=11 450), the excess risks for Black African women were diabetes (2·62, 2·27–3·03; p<0·0001), hypertension (2·13, 1·84–2·47; p<0·0001), and stroke (1·48, 1·12–1·95; p=0·006), and for Black Caribbean women, were diabetes (4·36, 3·88–4·91; p<0·0001), hypertension (3·02, 2·65–3·44; p<0·0001), and stroke (2·01, 1·65–2·47; p<0·0001). Significantly lower coronary heart disease risks were observed only for Black African women aged 40–69 years (0·80, 0·62–1·05; p=0·105), and women aged 70 years or older (0·57, 0·44–0·74; p<0·0001). Adjusting for deprivation accounted for approximately 10–15% attenuation of excess risk in these models. Additional adjustments for smoking and overweight led to further attenuation of excess risk for hypertension and stroke by 2–14% in both groups, and an increase in deficit of 4–15% for cardiovascular disease in Black African women. Among Black Caribbean women, ORs for cardiovascular disease remained non-significant compared with White women in the group aged 40–69 years, but became significantly lower among women aged 70 years or older (0·79, 0·65–0·95; p=0·0110), mainly due to smoking. InterpretationDeprivation and health-related behaviours made notable contributions to differences in cardiovascular risks between Black African, Black Caribbean, and White ethnic groups, consistent with earlier studies. FundingNational Institute of Health Research, Research for Patient Benefit Programme (NIHR202769).