Clinical characteristics and short-term outcomes of patients hospitalized with clinically diagnosed withdrawal syndromes: a retrospective observational cohort of 33 patients at a tertiary Poison Control Center in Vietnam

Background Withdrawal syndromes can range from mild autonomic and neuropsychiatric symptoms to severe complications requiring intensive monitoring and organ support. However, clinical data on hospitalized patients with withdrawal syndromes involving alcohol and other psychoactive substances in Vietnam remain limited. This study aimed to describe the demographic and clinical characteristics, laboratory findings, management, and short-term in-hospital outcomes of adults hospitalized with clinically diagnosed withdrawal syndromes and to explore differences between alcohol-related and non-alcohol-related cases. Methods We conducted a retrospective observational cohort study of adults hospitalized with clinically diagnosed withdrawal syndrome at the Poison Control Center, Bach Mai Hospital, Hanoi, Vietnam, between April 1, 2024, and December 31, 2025. Only the first admission for each patient was included. Patients were classified according to the primary substance considered responsible for the clinically diagnosed withdrawal syndrome. Demographic characteristics, admission clinical findings, laboratory results, treatment, organ-supportive interventions, and in-hospital outcomes were retrospectively extracted from medical records. Because of the small sample size and heterogeneity of the non-alcohol-related subgroup, between-group comparisons were considered exploratory. Results Among 33 patients included in the analysis, 30 (90.9%) were male and the mean age was 47.9 ± 13.1 years. Twenty-three patients (69.7%) were classified as having alcohol-related withdrawal and 10 (30.3%) as having non-alcohol-related withdrawal involving heroin, morphine, methamphetamine, ketamine, cannabis, electronic cigarettes, or nitrous oxide. Patients classified as having alcohol-related withdrawal had a higher median respiratory rate than those classified as having non-alcohol-related withdrawal (20 [IQR, 20–24] vs. 19.5 [IQR, 19–20] breaths/min; P = 0.008). Patients in the non-alcohol-related group had higher median AST and ALT concentrations. Seven patients (21.2%) required ICU admission, five (15.2%) required invasive mechanical ventilation, two (6.1%) underwent hemodialysis, and one (3.0%) underwent therapeutic plasma exchange. No in-hospital deaths occurred. Conclusions In this single-center retrospective cohort, alcohol-related withdrawal represented approximately 70% of clinically diagnosed withdrawal cases. Differences in respiratory rate and selected laboratory parameters were observed between the clinically classified groups; however, the small sample size, heterogeneity of the non-alcohol-related group, lack of standardized withdrawal-severity scores, and incomplete documentation of the temporal relationship between substance reduction or cessation and symptom onset limit definitive interpretation. Larger prospective studies using standardized diagnostic criteria and validated withdrawal-severity assessments are warranted.