A study of the association between atmospheric particulate matter and blood pressure in the population

This systematic review and meta-analysis was conducted to assess the association between the level of atmospheric particulate matter (PM) and the increase in blood pressure (BP) for different exposure terms (≤ 7 vs > 7 days) and age groups (< 65 vs ≥ 65 years). Some databases were searched to investigate the association between increased atmospheric PM (diameter < 2.5 mm [PM2.5] or < 10 mm [PM10]) and BP (systolic blood pressure [SBP] and diastolic blood pressure [DBP]). Among a total of 719 identified articles, 68 were reviewed in depth, of which only 20 satisfied the inclusion criteria. A significant association was found between PM10 levels and higher BP. The β values were 0.270mmHg (95% confidence interval [CI] 0.068-0.482) for SBP and 0.215mmHg (95% CI 0.058-0.372) for DBP. These β values mean that, for every 10 mg/m(3) increase in PM10, SBP increased by 0.270mmHg and DBP by 0.215 mmHg. Subgroup analyses were conducted for different exposure terms and age groups. A positive association was seen between PM2.5 and SBP. The β value of SBP was 0.495mmHg (95% CI 0.03-0.96) with every 10 mg/m(3) increase in PM2.5. There were no significant associations in both age groups and non-older groups. There was no significant association between PM2.5 and DBP, either in the overall effect or in the subgroup effects. In conclusion, significant associations were found between higher BP and higher PM10 levels, but the association between BP and levels of PM2.5 levels was unclear.