Blood pressure change and hypertension incidence among Ghanaians living in rural Ghana, urban Ghana and The Netherlands: a prospective cohort study

Background: Longitudinal data on blood pressure changes in sub-Saharan African populations are limited despite a high hypertension burden. This study analysed systolic blood pressure (SBP) change and hypertension incidence among people from Ghana living in rural Ghana, urban Ghana, people from Ghana living in The Netherlands and a Dutch European population living in Amsterdam, The Netherlands. Methods: The population-based Research on Obesity and Diabetes among African Migrants Prospective (RODAM-Pros) cohort study included adults aged ≥18 years at baseline (2012–2015) and follow-up (2019–2021) to study cardiovascular risk factors. At both timepoints, blood pressure (BP) was measured using a semiautomated device. Hypertension was defined as having a SBP ≥ 140 mmHg, diastolic BP ≥ 90 mmHg or the use of antihypertensive medication. We compared age-standardised SBP change and hypertension incidence between the geographical locations via linear and Poisson regression analyses, with adjustment for age, follow-up time, education, baseline BP, body mass index, renal function, and diabetes mellitus. The study protocol was approved by the respective ethics committees in Ghana and The Netherlands. Findings: Data from 632 people living in rural Ghana, 602 in urban Ghana, 861 Ghanaian, and 2038 Dutch people living in Amsterdam, were analysed (58.3% women, mean age at baseline 46.5 years, follow-up time 6·5 years). SBP increased most in women in rural Ghana (+9.5 mmHg, 95% confidence interval 7·3–11·7 mmHg), compared to +5·7 mmHg (3·6–7·7 mmHg) in urban Ghana, +2·2 mmHg (0·7–3·7 mmHg) in Ghanaian women in Amsterdam and −0·4 mmHg (−1·2 to 0·4 mmHg) in Dutch women. In men, SBP increased +5·5 mmHg (2·6–8·4 mmHg) in rural Ghana, +6·1 mmHg (2·8–9·5 mmHg) in urban Ghana, +2·1 mmHg (0·4–3·8 mmHg) in Ghanaian men in Amsterdam, and +0·3 mmHg (−0·5 to 1·1 mmHg) in Dutch men. Hypertension incidence ranged from 20·7% (95% confidence interval 14·3–29·2%) in men in rural Ghana to 34·2% (23·3–49·1%) in urban Ghana, vs. 27·9% (19·8–38·5%) in Ghanaian men in Amsterdam and 14·5% (11·8–17·6%) in Dutch men. Among women, incidence was 29·0% (23·1–35·9%) in rural Ghana, 27·6% (21·4–35·3%) in urban Ghana, 34·4% (26·0–45·4%) in Ghanaian women in Amsterdam, and 7·2% (5·6–9·2%) in Dutch women. Hypertension incidence rate ratios did not differ across populations, regardless of adjustment for covariates. Interpretation: SBP and hypertension increases were more pronounced in rural and urban Ghana than among migrants from Ghana in The Netherlands, suggesting that urbanisation of cardiovascular risk profile now extends to rural sub-Saharan Africa. Funding: European Research Council (grant number 772244).