The relationship between long-term exposure to PM_2.5 and hypertension in women：A meta-analysis

Gender difference and PM_2.5 exposure all have effects on hypertension, change of estrogen level in different women's stage bring complex influence on blood pressure. Then we conduct this meta-analysis to investigate the association between long-term exposure (at least one year) to fine particulate matter (PM_2.5) and hypertension in adult non-pregnant women.

Four major databases: PubMed, Cochrane Library, Web of Science and Embase were searched with specific search terms, and 11 studies were finally selected. The meta-analysis module of software Stata 12.0 was used for data processing with the effect values hazard ratio (HR) and odds ratio (OR) respectively.

After sensitivity analysis, we removed a study with highly heterogeneity and finally included 10 studies. Meta-analysis results showed that exposure to PM_2.5 (per 10 μg/m³ increase) was associated with hypertension in non-pregnancy adult women, HR = 1.23, 95%CI: 1.08-1.40; OR = 1.07, 95%CI: 1.00-1.14. And subgroup analysis showed that menopause, non-White and diabetes are the key risk factors of hypertension when exposed to PM_2.5.

This is the first meta-analysis to explore the association between PM_2.5 and non-pregnancy women, and calculate OR and HR respectively for the first time. Exposure to PM_2.5 could increase the risk of hypertension in non-pregnancy women, and the combined 'HR' was much higher than 'OR'.