The Influence of Smoking on Pulmonary Tuberculosis in Diabetic and Non-Diabetic Patients

Abstract

BackgroundBoth smoking and diabetes can increase the risk and influence the manifestations and outcomes of tuberculosis (TB). It is not clear whether the influence of smoking on pulmonary TB differs between non-diabetic and diabetic patients. Herein, we assessed the manifestations and outcomes of TB in relation to smoking in both diabetic and non-diabetic TB patients.Methodology/Principal FindingsAll diabetic culture-positive pulmonary TB patients notified from 2005–2010 at three teaching hospitals in Taiwan were enrolled. A culture-positive pulmonary TB patient without DM who was notified to the health authority immediately prior to each diabetic TB patient was selected for comparison. The 972 patients in this study cohort included 365 (37.6%) non-diabetic non-smokers, 149 (15.3%) non-diabetic smokers, 284 (29.2%) diabetic non-smokers, and 174 (17.9%) diabetic smokers. The adjusted relative risk of a pretreatment positive smear for a smoker compared with a non-smoker was 2.19 (95% CI 1.38–3.47) in non-diabetic patients and 2.23 (95% CI 1.29–3.87) in diabetic culture-positive pulmonary TB patients. The adjusted relative risk for a positive smear among diabetic smokers was 5.61 (95% CI 3.35–9.41) compared with non-diabetic non-smokers. Smoking was significantly associated with an increased frequency of bilateral lung parenchyma involvement (AdjOR 1.84, 95% CI 1.16–2.93), far-advanced pulmonary TB (AdjOR 1.91, 95% CI 1.04–3.50), cavitary lesions (AdjOR 2.03, 95% CI 1.29–3.20), and unfavorable outcomes of TB (AdjOR 2.35, 95% CI 1.02–5.41) in non-diabetic patients. However, smoking was not associated with cavitary lung parenchyma lesions regarding the location, number or size of the cavity in diabetic TB patients.Conclusions/SignificanceSmoking and diabetes have joint effects on a pretreatment positive smear. Diabetic smokers had more than a 5-fold increased risk of a pretreatment positive smear than did non-diabetic non-smokers, indicating remarkable joint effects of diabetes and smoking on the risk of TB transmission.

The impact of smoking on clinical characteristics and treatment outcome of patients with pulmonary tuberculosis

“…We obtained the same results concerning comorbidities. Our study was not able to confirm the existing evidence that the association of smoking and diabetes increases the risk of developing TB, probably because among our patients, smokers suffering from TB were mostly middle-aged persons who did not suffer from diabetes mellitus [23,25]. Older patients suffering from TB who were treated for diabetes mellitus were rarely smokers.…”

“…A significant difference was detected in relation to patients' sex. Smokers suffering from TB were mostly middle-aged men, between 30 and 49 years of age, who were manual laborers [23]. Among the non-smokers, ill with TB were mainly females between 20 and 29 years of age, from the rural environment.…”

Complying with the United Nations' Sustainable Development Goals: A case of the Malaysian ageing population

“…More than half of the respondents (n=241, 56.2%) agreed that smoking increases the risk of TB infection, while some confessed they did not know (n=160, 37.3%). According to Bai, Lee, Chien, Suk, and Chiang (2016), TB patients who smoke cigarettes possessed nearly twice the risk of TB infection of non-smokers. In fact, smokers (with TB disease) have a nine times greater risk of mortality than non-smokers (Hutahaean, 2013;Zhang et al, 2019).…”

Should tobacco control intervention be implemented into tuberculosis control program?

“…Smoking has been reported to be significantly associated with positive smear and cavitary pulmonary TB [12], thus may promote transmission of TB [9,10]. Bai et al assessed the manifestations in relation to smoking in both diabetic and non-diabetic TB patients [13]. They reported that the adjusted relative risk of a pretreatment positive smear for a smoker compared with a non-smoker was 2.…”

“…Studies have reported that smoking is associated with delayed sputum conversion and unfavorable treatment outcomes [13,14]. Gegia et al reported that current smokers had an increased risk of poor treatment outcome (aRR 1.7; 95% CI: 1.0-2.9) compared with those who had never smoked in Georgia [15].…”