Non-communicable respiratory disease and air pollution exposure in Malawi: a prospective cohort study. Issue 3 (20th February 2020)

• Record Type: Journal Article
• Authors: Rylance, Sarah; Jewell, Chris; Naunje, Andrew; Mbalume, Frank; Chetwood, John D; Nightingale, Rebecca; Zurba, Lindsay; Flitz, Graham; Gordon, Stephen B; Lesosky, Maia; Balmes, John R; Mortimer, Kevin
• Is Part Of: Thorax. Volume 75:Issue 3(2020)
• Page Start: 220
• Page End: 226
• Publication Date: 2020-02-20
• Subjects: clinical Epidemiology -- lung Physiology; Chest -- Diseases -- Periodicals; Thorax; Chest -- Diseases; Periodicals; Periodicals; 617.54
• DOI: 10.1136/thoraxjnl-2019-213941
• Languages: English
• ISSNs: 0040-6376

Abstract

Abstract : Rationale: There are no population-based studies from sub-Saharan Africa describing longitudinal lung function in adults. Objectives: To explore the lung function trajectories and their determinants, including the effects of air pollution exposures and the cleaner-burning biomass-fuelled cookstove intervention of the Cooking and Pneumonia Study (CAPS), in adults living in rural Malawi. Methods: We assessed respiratory symptoms and exposures, spirometry and measured 48-hour personal exposure to fine particulate matter (PM2.5 ) and carbon monoxide (CO), on three occasions over 3 years. Longitudinal data were analysed using mixed-effects modelling by maximum likelihood estimation. Measurements and main results: We recruited 1481 adults, mean (SD) age 43.8 (17.8) years, including 523 participants from CAPS households (271 intervention; 252 controls), and collected multiple spirometry and air pollution measurements for 654 (44%) and 929 (63%), respectively. Compared with Global Lung Function Initiative African-American reference ranges, mean (SD) FEV1 (forced expiratory volume in 1 s) and FVC (forced vital capacity) z-scores were −0.38 (1.14) and −0.19 (1.09). FEV1 and FVC were determined by age, sex, height, previous TB and body mass index, with FEV1 declining by 30.9 mL/year (95% CI: 21.6 to 40.1) and FVC by 38.3 mL/year (95% CI: 28.5 to 48.1). There was decreased exposure to PM2.5 in those with access to a cookstove but no effect on lung function. Conclusions: We did not observe accelerated lung function decline in this cohort of Malawian adults, compared with that reported in healthy, non-smoking populations from high-income countries; this suggests that the lung function deficits we measured in adulthood may have origins in early life.