The Burden of Hypertension in an Oil- and Gas-Polluted Environment: A Comparative Cross-Sectional Study

Background: Evidence of positive association between traffic-related air pollution and elevated blood pressure has been published widely. However, the risk of hypertension and prolonged exposure to crude oil pollution and gas flares remains unexplored.

Methods: We recruited 2,028 residents (aged 18-80) in a cross-sectional survey of both oil/gas polluted and nonpolluted communities in the Niger Delta region of Nigeria. Prevalence and risk of hypertension, anthropometric indices, lifestyle and sociodemographic factors, and cardiovascular comorbidities were examined and compared between the 2 groups. Hypertension was defined as blood pressure ≥140/90mm Hg or on antihypertensive medication. Both univariate and multivariate logistic regression models were used to examine factors associated with hypertension. Model fits statistics were used to assess the parsimonious model and predictive power.

Results: More than one-third of participants were hypertensive (37.4%). Half of the participants were from oil-polluted areas (51%). Only 15% of participants reported family history of hypertension. In the adjusted model, participants living in oil-polluted areas were almost 5 times as likely to have developed hypertension (adjusted odds ratio (aOR) = 4.85, 95% confidence interval (CI): 1.84-12.82) compared to participants in unpolluted areas. Age modifies the association between pollution status and risk of hypertension. For every 10 years increase in the age of the participants, the odds of developing hypertension increased by 108% (aOR = 2.08, 95% CI: 1.77-2.43).

Conclusion: The results suggested that exposure to oil/gas pollution may be associated with an increased risk of hypertension. Our findings need to be further investigated in longitudinal studies.