Post-tuberculous lung function impairment in a tuberculosis reference clinic in Cameroon

Abstract

BackgroundAfter completion of treatment, a proportion of pulmonary TB (pTB) patients experience lung function impairment which can influence their quality of life. This study aimed to determine the prevalence of lung function impairment in patients treated for pTB and investigate its associated factors. MethodsA cross-sectional study was conducted in TB clinic of the Douala Laquintinie Hospital in Cameroon. Patients aged 15 and above who were treated for pTB between 2008 and 2012 were included in the study. Demographic data, respiratory symptoms prior TB diagnosis, comorbidities and chest radiography findings prior to TB treatment were collected. All participants underwent spirometric measurements. Airflow obstruction was defined as a post-bronchodilation FEV1/FVC <70% with FVC >80%, restrictive defects as an FEV1/FVC ratio of ≥70% with an FVC <80% predicted, and mixed defects as FVC of <80% predicted and an FEV1/FVC ratio of <70%. Lung function impairment was defined by the presence of at least one of these three abnormalities. Logistic regression analysis was employed to investigate risk factors of lung function impairment. ResultsOf a total of 269 participants included in the study, 146 (54.3%) were male. The median age of participants was 33 years. The median duration of symptoms before diagnosis of TB was 4 weeks [interquartile range (IQR) 3-8]. The prevalence of lung function impairment was 45.4% (95% CI 39–51). The multivariate analysis identified duration of symptoms [OR 1.08; 95% CI (1.01–1.15)] and fibrotic pattern [OR 3.54; 95% CI (1.40–8.95)] as independent risk factors for lung function impairment. ConclusionPost-tuberculous pulmonary function impairment is frequent in Douala. Sensitization of patient with symptoms of pulmonary TB for an earlier visit to healthcare facilities could reduce the impact of pTB on lung function of patients.