A new study in the Journal of Child and Adolescent Psychopharmacology estimates the incidence of neuroleptic malignant syndrome (NMS), a potentially fatal adverse effect of antipsychotic treatment, among individuals aged 5–24 years.

Wayne Ray, Ph.D., from the Vanderbilt University School of Medicine, and co-authors, used national Medicaid data from 2004–2013 to identify patients beginning antipsychotic treatment and calculated the incidence of NMS during antipsychotic use.

The investigators identified five factors that independently predicted increased NMS incidence: age 18–24 years; schizophrenia spectrum and other psychotic disorders; neurodevelopmental disorders; antipsychotic dose >200 mg chlorpromazine-equivalents; and first-generation antipsychotics.

“Patients with four or five of these factors had more than 100 times the incidence of those with none,” reported the investigators.

“These data provide a basis for early identification of children and youth at elevated risk for NMS for whom monitoring for signs of this life-threatening syndrome could be increased, potentially leading to earlier detection and improved outcomes.”

Paul E. Croarkin, DO, MS, editor-in-chief of the Journal of Child and Adolescent Psychopharmacology, says, “Neuroleptic malignant syndrome is rare, serious, and previously understudied in children and adolescents. This important paper by Dr. Ray and colleagues has illuminated risk factors with immediate utility for clinical practice and provided a foundation for future research.”