The relationship between exposure to ambient particulate matter (PM) and hypertension in humans is controversial. The aim of the present meta-analysis was to quantify the predictability of ambient PM on the risk of incident hypertension in humans. The selection criteria included the studies that could provide quantitative estimates of the change in hypertension prevalence linked with exposure to either indicator of PM. The health outcome of “hypertension” was defined as systolic blood pressure (SBP) of 140 mmHg and greater and/or diastolic blood pressure (DBP) of 90 mmHg or greater and/or taking antihypertensive drugs or diagnosis by a physician or self-reported hypertension. A total of 647 studies were initially identified through online database searches, and finally five studies met the inclusion criteria. The combined results of reported relative risk from the five included studies revealed that ambient PM was positively associated with hypertension (OR = 1.03; 95% CI: 0.99–1.06), but this was not statistically significant. When stratified by the PM size, the results showed that the odds ratio for hypertension increased by 1.03 (95% CI: 0.93–1.14) per 10 μg/m3 increase in PM2.5, 1.04 (95% CI: 0.98–1.10) in PM10, and 0.99 (95% CI: 0.92–1.07) in PM2.5–10. In conclusion, to get more information about the associations between PM and hypertension, many studies need to be undertaken further to clarify these relationships.
Part of the book: Update on Essential Hypertension