Risk factors for pulmonary tuberculosis in patients with chronic obstructive airway disease in Taiwan: a nationwide cohort study
1 Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, No. 1, Roosevelt Road, Sec. 4, Taipei 10617, Taiwan
2 Department of Internal Medicine, Buddhist Tzu Chi General Hospital, Taipei, Taiwan
3 School of Medicine, Tzu Chi University, No.701, Zhongyang Road, Sec. 3, Hualien 97004, Taiwan
4 Department of Pharmacy, Buddhist Tzu Chi General Hospital, Taipei Branch, 289, Jianguo Road, Xindian District, New Taipei City 23142, Taiwan
5 Department of Traumatology, National Taiwan University Hospital, Taipei, Taiwan
6 Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
7 Department of Laboratory Medicine, National Taiwan University Hospital, No. 7, Chung-Shan South Road, Taipei 100, Taiwan
BMC Infectious Diseases 2013, 13:194 doi:10.1186/1471-2334-13-194Published: 30 April 2013
An association between chronic obstructive pulmonary disease (COPD) and tuberculosis (TB) has been described, mainly due to smoking and corticosteroid use. Whether inhaled corticosteroid (ICS) therapy is associated with an increased risk of TB remains unclear.
We selected COPD cases by using six diagnostic scenarios and control subjects from a nationwide health insurance database, and applied time-dependent Cox regression analysis to identify the risk factors for TB.
Among 1,000,000 beneficiaries, 23,594 COPD cases and 47,188 non-COPD control subjects were selected. Cox regression analysis revealed that age, male gender, diabetes mellitus, end-stage renal disease, and cirrhosis, as well as COPD (hazard ratio = 2.468 [2.205–2.762]) were independent risk factors for TB. Among the COPD cases, those who developed TB received more oral corticosteroids and oral β-agonists. Time-dependent Cox regression analysis revealed that age, male gender, diabetes mellitus, low income, oral corticosteroid dose, and oral β-agonist dose, but not ICS dose, were independent risk factors for TB. The identified risk factors and their hazard ratios were similar among the COPD cases selected using different scenarios.
Keeping a high suspicion and regularly monitoring for the development of pulmonary TB in COPD patients are necessary, especially for those receiving higher doses of oral corticosteroids and other COPD medications. Although ICS therapy has been shown to predispose COPD patients to pneumonia in large randomized clinical trials, it does not increase the risk of TB in real world practice.