Gender, race/skin colour and incidence of hypertension in ELSA-Brasil: an intersectional approach

Objective Race and gender inequities in the incidence of hypertension (HTN) are well documented; however, few empirical investigations looked into these associations, considering the synergies and heterogeneous experiences of intersectional gender and race/skin colour groups. This study investigated the association of intersectional identities defined by gender and race/skin colour with HTN incidence, and verified whether they are affected by educational level in adulthood. Design We used the Longitudinal Study of Adult Health (ELSA-Brasil) data to estimate the incidence of HTN between visits 1 (2008-2010) and 2 (2012-2014), in 8528 participants without hypertension at visit 1. HTN was defined as systolic blood pressure >= 140 mmHg, or diastolic blood pressure >= 90 mmHg, or use of antihypertensive drugs. Generalized linear models with Poisson distribution and log link function were used to assess the associations. Results The incidence of HTN was 43.4/1000 person-years, ranging from 30.5/1000 in White women to 59.4/1000 in Black men. After adjusting by age and family history of HTN, the incidence rate ratio (IRR) was higher in Black men (2.25; 95%CI: 1.65-3.08), Brown (Pardo) men (1.89; 95%CI: 1.59-2.25), Black women (1.85; 95%CI: 1.50-2.30), Brown (Parda) women (1.47; 95%CI: 1.31-1.67) and White men (1.76; 95%CI: 1.49-2.08), compared to White women. These associations were maintained even after considering socioeconomic, behavioural and health mediators in the model. No interaction was found between education level and intersectional identities in the IRRs observed. Conclusion By using an intersectional approach, we showed the complex relations between race/skin colour and gender inequities in the incidence of HTN, pointing not only that Black men have the highest risk of developing HTN, but also that the risk of HTN is greater in Black women than in White men, when compared to White women.