Prevalence of chronic obstructive pulmonary disease and associated risk factors in Uganda (FRESH AIR Uganda): a prospective cross-sectional observational study

Abstract

BACKGROUND: In sub-Saharan Africa, little is known about the damage to respiratory health caused by biomass smoke and tobacco smoke. We assessed the prevalence of chronic obstructive pulmonary disease (COPD) and related risk factors in a rural region of Uganda. METHODS: We did this prospective observational cross-sectional study in rural Masindi, Uganda. We randomly selected people above the age of 30 years from 30 villages. Trained local health-care workers asked validated questionnaires and administered spirometry to participants. We defined COPD as FEV1:FVC less than the lower limit of normal. We calculated prevalence of COPD and tested its association with risk factors. FINDINGS: Between April 13, and Aug 14, 2012, we invited 620 people to participate, of whom 588 provided acceptable spirometry and were analysed. Mean age was 45 years (SD 13·7); 297 (51%) were women. 546 (93%) were exposed to biomass smoke. The prevalence of COPD was 16·2% (15·4% in men, 16·8% in women). Prevalence was highest in people aged 30-39 years (17 [38%] of 45 men, 20 [40%] of 50 women). 20 (44%) of 45 men with COPD were current smokers (mean age 40 years, SD 7·5), 11 (24%) were former smokers (mean age 49 years, SD 11·0); four [8%] of 50 women were current smokers (mean age 52 years, SD 18·1), nine (18%) were former smokers (mean age 64 years, SD 16·2). Mean Clinical COPD Questionnaire score was 0·81 (SD 0·78), mean Medical Research Council dyspnoea score was 1·33 (SD 0·65); 28 (30%) of 95 patients had had one or more exacerbations past 12 months. COPD was associated with wheeze (odds ratio 2·17, 95% CI 1·09-4·34; p=0·028) and being a former smoker (1·96, 1·07-3·59; p=0·029). INTERPRETATION: In this rural district of Uganda, COPD starts early in life. Major risk factors were biomass smoke for both sexes and tobacco smoke for men. In addition to high smoking prevalence in men, biomass smoke could be a major health threat to men and women in rural areas of Uganda. FUNDING: International Primary Care Respiratory Group.