Association of oil spill cleanup-related hydrocarbon exposure with hypertension and blood pressure in the Gulf Long-term Follow-up Study.

BACKGROUND

Although several studies have demonstrated a relationship between crude oil exposures and cardiovascular disease, little is known about associations with hypertension.

OBJECTIVE

Our study examined associations of oil spill cleanup-related benzene, toluene, ethylbenzene, xylene, and n-hexane (BTEX-H) exposures with hypertension prevalence and blood pressure (BP).

METHODS

Participants comprised 6693 Deepwater Horizon (DWH) oil spill cleanup and response workers who completed a home visit in the Gulf Long-term Follow-up Study. Cumulative exposures to individual components of BTEX-H and total BTEX-H (ppb-days) were estimated via a job-exposure matrix linking detailed self-reported DWH response and cleanup work histories to air monitoring data. Trained examiners measured BP during the home visit. We defined hypertension as systolic ≥140 or diastolic ≥90 mmHg, or self-reported antihypertensive medication use. We used modified Poisson regression to calculate prevalence ratios (PR) and 95% confidence intervals (CI) for associations of individual BTEX-H and total BTEX-H quartiles with hypertension. Linear regression was used to estimate exposure effects on systolic and diastolic BP. We used quantile g-computation to estimate the joint effect of the BTEX-H mixture.

RESULTS

BTEX-H exposures were modestly associated with hypertension prevalence and systolic and diastolic BP. Strongest associations with hypertension were observed in quartile 4 versus quartile 1 of most exposures (range of PRs: 1.06-1.15). The BTEX-H mixture was associated with small elevations in systolic (β = 0.60 mmHg, 95% CI: 0.26, 0.94) and diastolic (β = 0.49 mmHg, 95% CI: 0.24, 0.73) BP.

CONCLUSION

BTEX-H exposures were associated with small elevations in hypertension prevalence and blood pressure.