Long-term air pollution exposure and sex-specific cardiometabolic health trajectories: the Framingham Offspring Study

Abstract

BACKGROUND AND AIM: We assessed whether annual average particulate matter (PM2.5) exposure modified sex-specific cardiometabolic health (CMH) trajectories. METHODS: We evaluated 3113 Framingham Offspring Study participants by classifying their CMH at each of nine examination cycles (1971-2014) into six categories: (1) cardiometabolically healthy and no cardiometabolic medications, (2) 1-2 sub-clinical risk factors (body mass index ≥25 kg/m2, waist circumference ≥102 cm in men/≥88 in women, total cholesterol ≥200 mg/dL, low-density lipoprotein ≥130 mg/dL, high-density lipoprotein 40 mg/dL in men/50 in women, triglycerides ≥150 mg/dL, systolic blood pressure ≥120 mmHg, diastolic blood pressure ≥80 mmHg, fasting plasma glucose ≥100 mg/dL), (3) 3-4 sub-clinical risk factors, (4) one of hypertension, diabetes, or chronic kidney disease, (5) clinical cardiovascular disease or ≥2 cardiometabolic diagnoses from category four, and (6) cardiovascular-related mortality. Each participants’ annual average PM2.5 exposure (in 2000) was previously assessed using a validated model. We calculated sex-specific CMH trajectories with age as the time scale. We determined the number and polynomial order of trajectory groups based on the Bayesian information criterion and an average posterior probability 0.8 for each group. We identified trajectories based on average CMH status at age 35 years (good 2; intermediate = 2-3; poor 3) and trajectory slope through age 70 years (fast aging ≥2 average increase in group classification; medium = 1-2 average increase; slow ≤1 average increase). RESULTS:Men were more likely to have intermediate or poor CMH at age 35 years, but women were more likely to experience intermediate or fast aging between 35-70 years of age. PM2.5 exposure did not modify average CMH status at 35 years or trajectory slope for either men or women. Higher PM2.5 exposure was significantly associated with decreased likelihood of membership in the healthiest CMH trajectory group for both men and women. CONCLUSIONS:Long-term PM2.5 exposure is associated with CMH trajectories throughout middle age. KEYWORDS: Cardiovascular diseases, Obesity and metabolic disorders, Particulate matter, Female