Khat chewing, poly-substance use, and lower urinary tract symptoms: a cross-sectional analysis among Yemeni medical university students

BACKGROUND: Khat (Catha edulis) chewing is highly prevalent in Yemen, but its potential urological effects are poorly characterized. The pharmacological action of its alkaloids on alpha-adrenergic receptors suggests a plausible link to voiding dysfunction. This study explored the association between khat chewing patterns, concurrent stimulant use, and lower urinary tract symptom (LUTS) severity. METHODS: In this cross-sectional study, 112 medical and paramedical university students from seven Yemeni governorates completed a structured digital questionnaire being recruited via convenience sampling. LUTS severity was assessed using the International Prostate Symptom Score (IPSS). Exposure variables included khat chewing (status, duration, daily hours), coffee, soda, and tobacco use. Participants were categorized into poly-substance use clusters. Multivariable linear and logistic regression models identified predictors of LUTS, adjusting for confounders including age and sex. RESULTS: Among participants (mean age 24.3±5.7 years), 86 (76.8%) were current khat chewers. A significant dose-response relationship was observed. Each additional hour of daily chewing was associated with a 1.85-point increase in IPSS score (95% CI: 1.32-2.38; p