Patients with prior history of pulmonary tuberculosis (TB) are at least 3-times more likely to develop chronic obstructive pulmonary disease (COPD), according to findings from a recent international study published in the journal Thorax.¹

Researchers from different parts of the globe collaborated in this cross-sectional analysis of data from “geographically diverse, low-resource settings” with an objective to analyse the association between COPD and past history of TB. These studies included 12,396 participants, aged 54 years (median). A little over half of the study population was male (51.5%).

Analysis revealed that 2.7% of the study subjects had a past history of TB. The overall prevalence of COPD was 8.8%, with prevalence ranging from 1.7% to 5.5% across the 13 settings of the study. Compared to patients who did not have previous TB (8.3%), the prevalence of COPD was higher among those who had previous TB (25.7%). The adjusted odds of having COPD was 3.78 times higher for patients with previous TB than those without TB. “The attributable fraction of COPD due to previous tuberculosis disease in the study sample was 6.9%,” noted the authors. Participants with previous TB also had lower prebronchodilator Z-scores for FEV1 (-0.70), FVC (-0.44) and the FEV1:FVC ratio (0.63).

While smoking is a major cause of COPD, other factors too such as burning of biomass fuel and air pollution are other contributory factors. TB is being increasingly recognized as a risk factor for COPD.

This study has determined the risk of COPD secondary to TB giving credence to the interrelationship between prior TB and COPD. It further suggests previous pulmonary TB as “a significant and under-recognised risk factor for COPD and poor lung function” in developing countries. Awareness of this association would facilitate early diagnosis and treatment of COPD, especially a country like ours where TB is endemic and which bears the highest burden of TB globally. In another  study, Fan et al caution about the use of inhaled corticosteroids (ICS) in patients with prior TB due to the risk of recurrence of the infection.²

References

1. Kamenar K, et al. Previous tuberculosis disease as a risk factor for chronic obstructive pulmonary disease: a cross-sectional analysis of multicountry, population-based studies. Thorax. 2022 Nov;77(11):1088-1097. doi: 10.1136/thoraxjnl-2020-216500.
2. Fan H, et al. Pulmonary tuberculosis as a risk factor for chronic obstructive pulmonary disease: a systematic review and meta-analysis. Ann Transl Med. 2021 Mar;9(5):390. doi: 10.21037/atm-20-4576.