Prevalence of lung function impairment in cured pulmonary tuberculosis patients in Cotonou, Benin.

Setting: National teaching hospital for the management of respiratory diseases, Cotonou, Benin.

Objective: 1) To estimate the prevalence of lung function impairment (LFI) and associated factors in patients cured of pulmonary tuberculosis (PTB); and 2) to determine the link between human immunodeficiency virus (HIV) infection and LFI occurrence.

Design: We performed a cross-sectional study in cured patients with smear-positive TB (PTB+) treated between 2012 and 2015. We recruited two control groups of 70 HIV-infected (HIV+/TB-) and 70 HIV-negative participants without TB (HIV-/TB-). We performed spirometry in all participants to identify LFI (obstructive, restrictive or mixed) and the 6-min walk test (6-MWT) in PTB+ participants. We assessed the factors associated with LFI using logistic regression.

Results: Of 4711 subjects with PTB, 241 were contacted and 189 were included. The median age was 37 years; 128 (68.0%) were male. Overall, 85 cured PTB+ patients had LFI (45.0%). Extent of initial radiological lesions, time between symptom onset and treatment, and female sex were independently associated with LFI. Fifty-five (29.1%) cured PTB+ patients had an abnormal 6-MWT; those with LFI had a higher risk of poor exercise tolerance (OR 2.23; interquartile range 1.16-4.30). We did not find any association between HIV infection and LFI.

Conclusion: LFI is very common in cured PTB+ patients from Benin and significantly impacts exercise tolerance.