Prevalence and correlates of antipsychotic polypharmacy in children and adolescents receiving antipsychotic treatment*

Antipsychotic polypharmacy (APP), which is common in adults with psychotic disorders, is of unproven efficacy and raises safety concerns. Although youth are increasingly prescribed antipsychotics, little is known about APP in this population. We performed a systematic PubMed search (last update 26 January 2013) of studies reporting the prevalence of APP in antipsychotic-treated youth. Summary statistics and statistical tests were calculated at the study level and not weighted by sample size. Fifteen studies (n=58041, range 68-23183) reported on APP in youth [mean age=13.4 +/- 1.7 yr, 67.1 +/- 10.2% male, 77.9 +/- 27.4% treated with second-generation antipsychotics (SGAs)]. Data collected in these studies covered 1993-2008. The most common diagnoses were attention-deficit hyperactivity disorder (ADHD; 39.9 +/- 23.5%) and conduct disorder/oppositional defiant disorder (CD/ODD; 33.6 +/- 24.8). In studies including predominantly children (mean age=yr, N=5), the most common diagnosis were ADHD (50.6 +/- 25.4%) and CD/ODD (39.5 +/- 27.5%); while in studies with predominantly adolescents (mean age=13yr, N=7) the most common diagnoses were schizophrenia-spectrum disorders (28.6 +/- 23.8%), anxiety disorders (26.9 +/- 14.9%) and bipolar-spectrum disorders (26.6 +/- 7.0%), followed closely by CD/ODD (25.8 +/- 17.7). The prevalence of APP among antipsychotic-treated youth was 9.6 +/- 7.2% (5.9 +/- 4.5% in child studies, 12.0 +/- 7.9% in adolescent studies, p=0.15). Higher prevalence of APP was correlated with a bipolar disorder or schizophrenia diagnosis (p=0.019) and APP involving SGA+SGA combinations (p=0.0027). No correlation was found with APP definition [1d (N=10) vs. \u3e30-90d (N=5), p=0.88]. Despite lacking safety and efficacy data, APP in youth is not uncommon, even in samples predominantly consisting of non-psychotic patients. The duration, clinical motivations and effectiveness of this practice require further study