Smoking on treatment outcomes among tuberculosis patients

BACKGROUND: Smoking is a risk factor not only for the development of cancer and coronary heart disease but also for tuberculosis (TB). The aim of this study was to determine the prevalence of smoking in patients with TB, identify demographic and clinical characteristics associated with smoking and to evaluate TB treatment outcomes in the smokers.
METHOD: A retrospective cohort study of patients with TB was conducted at Khyber Teaching Hospital, Peshawar, Pakistan. All patients with pulmonary and extrapulmonary TB and those coinfected with HIV, hepatitis or diabetes mellitus were included in the study. The patients were categorized into smokers and nonsmokers. Treatment outcomes were evaluated by smear testing at the end of the treatment.
RESULTS: Of 472 enrolled subjects, 68 (14.4%) were smokers. The prevalence of smoking among male and female patients with TB was 11.8% and 2.5%, respectively. Univariate analysis indicated that the gender, age group and marital status of patients with TB were associated with smoking. The results indicated that patient gender (P = 0.05), age: 15 to 24 years (P = 0.05) and age >55 years (P = 0.004) were risk factors associated with smoking among TB patients. Of the 68 smokers with TB, the treatment outcomes among 54 patients (79.4%) were unsuccessful. The treatment outcomes was statistically significantly associated with smoking (odds ratio: 2.58, P = 0.004).
CONCLUSIONS: Findings from the current study proved smoking to be one of the main factors associated with the occurrence of TB and significantly reducing the outcomes of TB therapy.