Airborne phthalate exposures and hypertension in the Sister Study

Hypertension affects nearly a billion people globally, but the association between airborne phthalates and hypertension remains unclear.

We conducted a cross-sectional analysis of 47,465 women from the Sister Study. Exposure to airborne bis (2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), and dimethyl phthalate (DMP) was estimated using the US Environmental Protection Agency's 2005 National Air Toxics Assessment database linked to participants' addresses. Hypertension was defined as systolic blood pressure ≥ 140 mm Hg, or diastolic blood pressure ≥ 90 mm Hg, or use of antihypertensive medications. Prevalence ratios (PRs) and 95 % confidence intervals (CIs) were calculated using multivariable log-binomial regression. We further used quantile-based g-computation to assess the joint effect and conducted analyses stratified by race/ethnicity.

DEHP (PR _{Q4 vs Q1}=1.06, 95 % CI: 1.02-1.09, P trend=0.001), DBP (PR _{Q3 vs Q1}=1.04, 95 % CI: 1.00-1.07, P trend=0.02), and DMP (PR _{Q3 vs Q1}=1.03, 95 % CI: 1.00-1.06, P trend=0.8) were associated with increased hypertension risk. Associations of DEHP and DMP were stronger in women of other races/ethnicities compared to non-Hispanic White participants. A one quartile increase in the phthalate mixture was associated with a 2 % increase in hypertension prevalence (PR=1.02, 95 % CI:1.00-1.03, P = 0.02).

Airborne phthalate exposures were associated with higher hypertension prevalence, especially among women other than non-Hispanic White.