Abstract
BACKGROUND: Globally, undergraduate students exhibit a higher tendency towards tobacco and other substance use. Although there are almost 50,000 undergraduate medical students studying in Bangladesh currently, evidence regarding the prevalence of tobacco & other substance use among them is very limited, let alone the predictors. AIM: This research aims to investigate the prevalence of tobacco or other substance use among medical students in Bangladesh and to investigate the factors associated with tobacco or other substance use. METHODS: This cross-sectional study was conducted between May 2023 and August 2024 in sixteen medical colleges in Bangladesh. A total of 1,129 medical students were selected by convenience sampling, and data were collected using an online self-reported semi-structured questionnaire. Descriptive statistics, chi-square test, t-test, and multiple logistic regression model were used to report the study findings. RESULTS: The mean age of the students was 22.3 (± 2) years, with slightly higher female preponderance (52.3%). Out of 1129 medical students, tobacco or other substance use was prevalent in 154 (13.6%) students. The students most commonly used tobacco products (54.5%) followed by non-medical use of sedatives (26%) and cough syrup (18.8%). The odds of using tobacco or other substances increased with age and academic year. Male students (AOR: 1.41, 95%CI: [1.26, 1.59], p < 0.001), living at an off campus housing without family (AOR: 2.25, 95% CI: [1.02, 4.94], p = 0.043) and living in a medical college hostel (AOR: 2.1, 95% CI: [1.20, 3.67], p = 0.009), having tobacco or other substance use in family (AOR: 3.97, 95% CI: [2.64, 5.98], p < 0.001), and not willingly admitted to medical college (AOR:3.61, 95%CI: [2.20, 5.90], p < 0.001) were significant predictors of tobacco or other substance use. CONCLUSION: This study observed a high prevalence of tobacco or other substance use among medical students. Therefore, the factors associated with their tobacco or other substance use related behavior should be mitigated, and necessary provisions should be made available to help with the cessation of such use among the current users. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-025-25955-4.