Indoor air pollution and cognitive function among older Mexican adults.

BACKGROUND: A growing body of research suggests exposure to high levels of outdoor air pollution may negatively affect cognitive functioning in older adults, but less is known about the link between indoor sources of air pollution and cognitive functioning. We examine the association between exposure to indoor air pollution and cognitive function among older adults in Mexico, a developing country where combustion of biomass for domestic energy remains common.

METHOD: Data come from the 2012 Wave of the Mexican Health and Aging Study. The analytic sample consists of 13 023 Mexican adults over age 50. Indoor air pollution is assessed by the reported use of wood or coal as the household's primary cooking fuel. Cognitive function is measured with assessments of verbal learning, verbal recall, attention, orientation and verbal fluency. Ordinary least squares regression is used to examine cross-sectional differences in cognitive function according to indoor air pollution exposure while accounting for demographic, household, health and economic characteristics.

RESULTS: Approximately 16% of the sample reported using wood or coal as their primary cooking fuel, but this was far more common among those residing in the most rural areas (53%). Exposure to indoor air pollution was associated with poorer cognitive performance across all assessments, with the exception of verbal recall, even in fully adjusted models.

CONCLUSIONS: Indoor air pollution may be an important factor for the cognitive health of older Mexican adults. Public health efforts should continue to develop interventions to reduce exposure to indoor air pollution in rural Mexico.