2021-11-042025-07-282021-11-042021-11-040007-114510.1017/S0007114517003166https://ir.ntus.edu.tw/handle/987654321/65587Evidence regarding the association between BMI and mortality in tuberculosis (TB) patients is limited and inconsistent. We investigated the impact of BMI on TB-specific and non-TB-specific mortality with respect to different timing of death. All Taiwanese adults with TB in Taipei were included in a retrospective cohort study in 2012-2014. Multinomial Cox proportional hazards regression was used to evaluate the associations between BMI, cause-specific mortality and timing of death. Of 2410 eligible patients, 86.0 % (2061) were successfully treated, and TB-specific and non-TB-specific mortality occurred for 2.2 % (54) and 13.9 % (335), respectively. After controlling for potential confounders, underweight was significantly associated with a higher risk of all-cause mortality (adjusted hazard ratio (AHR) 1.57; 95 % CI 1.26, 1.95), whereas overweight was not. When cause-specific death was considered, underweight was associated with an increased risk of either TB-specific (AHR 1.85; 95 % CI 1.03, 3.33) or non-TB-specific death (AHR 1.52; 95 % CI 1.19, 1.95) during treatment. With joint consideration of cause-specific and timing of death, underweight only significantly increased the risk of TB-specific (AHR 2.23; 95 % CI 1.09, 4.59) and non-TB-specific mortality (AHR 1.81; 95 % CI 1.29, 2.55) within the first 8 weeks of treatment. This study suggests that underweight increases the risk of early death in TB patients during treatment.244 bytestext/htmlTuberculosisBMIUnderweightMortalityarticle