Association between Long-Term Ambient PM2.5 Exposure and Hypertension and Metabolic Syndrome among Ghanaian Adults

INTRODUCTION: Air pollution is a leading environmental risk factor for cardiovascular disease (CVD), yet its relationship with metabolic syndrome (MetS) and its components in sub-Saharan Africa are unclear. This study aimed to examine the association between long-term PM2.5 exposure and MetS (and its component conditions) in a Ghanaian adult cohort.

METHODS: We performed a cross-sectional analysis of 1,833 adults (40-60 years) from the Awi-Gen study. Long-term PM2.5 exposure (2007-2015) was estimated via a satellite-based model. MetS was defined using harmonized criteria. We used multivariable logistic regression with sequential adjustment for covariates.

RESULTS: A positive association was observed between PM2.5 and hypertension, while no association was found for MetS overall or its component conditions. Each 1 μg/m3 increase in PM2.5 was associated with 6% higher odds of hypertension (OR: 1.06, 95% CI: 1.02-1.11). PM2.5 quartiles also showed a dose-response relationship with hypertension (p-trend=0.003), with the highest exposure linked to a 50% greater likelihood of hypertension. The calculated population attributable fraction for PM2.5 and hypertension was 18.6%.

INTERPRETATION: In this rural Ghanaian population, long-term PM2.5 exposure was associated with hypertension but not with metabolic syndrome or its other components. These findings provide important evidence from an understudied sub-Saharan African population and support the integration of air quality management into cardiovascular disease prevention strategies.