Antipsychotic Medications and Mortality in Children and Young Adults

Importance Dose-related effects of antipsychotic medications may increase mortality in children and young adults. Objective To compare mortality for patients aged 5 to 24 years beginning treatment with antipsychotic vs control psychiatric medications. Design, Setting, and Participants This was a US national retrospective cohort study of Medicaid patients with no severe somatic illness or schizophrenia or related psychoses who initiated study medication treatment. Study data were analyzed from November 2022 to September 2023. Exposures Current use of second-generation antipsychotic agents in daily doses of less than or equal to 100-mg chlorpromazine equivalents or greater than 100-mg chlorpromazine equivalents vs that for control medications (alpha agonists, atomoxetine, antidepressants, and mood stabilizers). Main Outcome and Measures Total mortality, classified by underlying cause of death. Rate differences (RDs) and hazard ratios (HRs) adjusted for potential confounders with propensity score-based overlap weights. Results The 2 067 507 patients (mean [SD] age, 13.1 [5.3] years; 1 060 194 male [51.3%]) beginning study medication treatment filled 21 749 825 prescriptions during follow-up with 5 415 054 for antipsychotic doses of 100 mg or less, 2 813 796 for doses greater than 100 mg, and 13 520 975 for control medications. Mortality was not associated with antipsychotic doses of 100 mg or less (RD, 3.3; 95% CI, -5.1 to 11.7 per 100 000 person-years; HR, 1.08; 95% CI, 0.89-1.32) but was associated with doses greater than 100 mg (RD, 22.4; 95% CI, 6.6-38.2; HR, 1.37; 95% CI, 1.11-1.70). For higher doses, antipsychotic treatment was significantly associated with overdose deaths (RD, 8.3; 95% CI, 0-16.6; HR, 1.57; 95% CI, 1.02-2.42) and other unintentional injury deaths (RD, 12.3; 95% CI, 2.4-22.2; HR, 1.57; 95% CI, 1.12-2.22) but was not associated with nonoverdose suicide deaths or cardiovascular/metabolic deaths. Mortality for children aged 5 to 17 years was not significantly associated with either antipsychotic dose, whereas young adults aged 18 to 24 years had increased risk for doses greater than 100 mg (RD, 127.5; 95% CI, 44.8-210.2; HR, 1.68; 95% CI, 1.23-2.29). Conclusions and Relevance In this cohort study of more than 2 million children and young adults without severe somatic disease or diagnosed psychosis, antipsychotic treatment in doses of 100 mg or less of chlorpromazine equivalents or in children aged 5 to 17 years was not associated with increased risk of death. For doses greater than 100 mg, young adults aged 18 to 24 years had significantly increased risk of death, with 127.5 additional deaths per 100 000 person-years.