Exposure to household air pollution from wood-burning cookstoves and C-reactive protein among women in rural Honduras

Abstract

Household air pollution from the burning of solid fuels is estimated to cause 1.6 million deaths annually and is an important risk factor for cardiovascular disease. Cardiovascular disease risk can be assessed by C-reactive protein (CRP) levels via dried blood spots in resource-limited settings. We evaluated the cross-sectional association of household air pollution and CRP among 106 female primary cooks in rural Honduras using wood-burning traditional or Justa stoves. We measured 24-hour gravimetric kitchen and personal fine particulate matter (PM2.5) and black carbon concentrations. Finger-stick blood samples were collected on filter paper for CRP analysis. Associations were evaluated using linear regression, adjusted for age, body mass index (BMI), education, and number of household assets. We assessed effect modification by risk factors age, BMI, glycated hemoglobin, and blood pressure.The median (25th-75th percentile) 24-hour average personal PM2.5 concentrations among traditional stoves users and Justa stove users were: 115 µg/m3 (65-154 µg/m3); 52 µg/m3 (39-81 µg/m3), respectively. Kitchen PM2.5 and kitchen and personal black carbon were also higher among traditional stove users. In adjusted analyses, higher concentrations of 24-hour average kitchen and personal PM2.5 and black carbon were associated with higher levels of CRP (e.g., a 25% increase in personal PM2.5 exposure was associated with a 10.5% increase in CRP [95% confidence interval: 1.2-20.6]). We only observed evidence of effect modification by levels of glycated hemoglobin. The association between personal PM2.5 and CRP was stronger among women with normal glycated hemoglobin levels compared to women with elevated glycated hemoglobin levels (p-interaction=0.01).Our results indicate that higher exposure to household air pollution is associated with higher levels of CRP among women in rural Honduras. The effect modification results only among women with normal blood sugar is contrary to our hypothesis and requires additional investigation. This does not necessarily reflect the policies of EPA.