Prevalence of modifiable risk factors of tuberculosis and their population attributable fraction in Iran: A cross-sectional study

BACKGROUND: The mycobacterium tuberculosis (Mtb) is necessary for the morbidity of tuberculosis (TB), but it is insufficient. Many risk factors increase the risk of disease among infected people. We aimed to estimate the prevalence of modifiable risk factors of TB and their related population attributable fraction (PAF) in the marginal population of Markazi province in Iran. DESIGN: In this cross-sectional study, the prevalence of the modifiable risk factors of TB was estimated. We designed and validated a questionnaire to determine the risk factors. The measures of association for the modifiable risk factors of TB were obtained via the review of published literature. We calculated the PAF for each modifiable risk factor. RESULTS: Out of the 1275 calculated sample size, 1146 people participated in this study, and the participation rate was 89.9%. The mean age was 39.26. Out of 1146 participants, 76% did not know anything regarding TB. The highest prevalence was related to the lack of physical activity (58.73%), lack of fish consumption (50.79%), lack of red meat consumption (21.20%), and secondhand smoke (19.02%). The highest PAF was related to secondhand smoke; this value based on the crude relative risk (RR) and crude odds ratio (OR) was 24.54% and 23.44%, respectively. Based on crude hazard ratio (HR) and crude OR, the PAF for smoking was 14.81% and 11.19%, respectively. PAF for lack of BCG vaccination based on the crude OR was 14.79%. CONCLUSION: Based on this study’s results, poor nutrition, secondhand smoke, smoking, lack of BCG vaccination, and diabetes are the main prevalent modifiable risk factors for TB. The highest PAF for TB was related to secondhand smoke, smoking, lack of BCG vaccination, and diabetes.