Physician Patient-Sharing Networks and Prescription of Psychotropic Polypharmacy in the Treatment of Children and Adolescents with Mental Disorders

BACKGROUND: Psychotropic polypharmacy (PP) is highly prevalent in the treatment of pediatric mental disorders. However, literature studying the risk factors associated with use of PP is scarce, especially with respect to whether risk factors differ between patients treated by single prescriber (SP) versus multiple prescribers (MP). OBJECTIVE: To advance the understanding of the prevalence of and risk factors associated with long-term multiclass psychotropic polypharmacy (PP) among children and adolescents with mental/behavioral disorders in a Texas Medicaid population. METHODS: A retrospective cross-sectional study was conducted using the 2013-2015 administrative claims data from a Medicaid Managed Care Organization (Texas Children’s Health Plan). The study included individuals: a) ≤18 years of age, b) diagnosed with a mental disorder, and c) had at least one pharmacy claim of psychotropic medication during the study period. Based on the number of prescribers involved in the treatment the individuals were categorized into two groups: a) single prescriber (SP) and b) multiple prescribers (MP). PP was defined as the receipt of ≥ 2 psychotropic medications from different drug classes concurrently for 60 days or more. Two separate logistic regression models (SP and MP) were conducted to determine associations between PP and patients demographics, diagnosis, clinical complexity and prescriber characteristics. The Farilie decomposition method (extension of Blinder-Oaxaca [BO] decomposition) was further applied to test the differences in receipt of psychotropic polypharmacy between patients treated by PCPs vs those treated by specialists RESULTS: A total of 24,147 children and adolescents met the inclusion criteria. The prevalence of multiclass PP was 20.09%. Other significant factors associated with PP were patient race and diagnosis of bipolar disorders and depression, as well as the number of mental disorders diagnosed and number of prescribers involved in treatment (MP group only). The most prominent factor associated with the receipt of psychotropic polypharmacy was the involvement of specialist in the treatment. Patients with a specialist involved in the treatment had 5.3 times and 3.6 times higher likelihood of receiving PP in the SP and MP groups respectively (SP: OR=5.324; 95% CI 4.620-6.136 & MP: OR=3.571; 95% CI 3.199-3.985). Other factors positively associated with psychotropic polypharmacy were being a male, Caucasian race, diagnosis of ADHD and bipolar disorder(s). The number of mental/behavioral disorder diagnosed and the number of providers involved in treatment were unique predictors positively associated with polypharmacy in the multiple prescriber group. The Farilie decomposition analysis estimated that the observed need factors explained only approximately 25% of the difference in the receipt of PP between patients seen by PCPs and specialists within both SP and MP groups. CONCLUSIONS: The most prominent factor associated with PP was involvement of a specialist in the treatment of mental/behavioral disorders. Only a quarter of the difference between PCPs and specialists with respect to prescription of PP was explained by observable need factors, underscoring the drastically different prescribing habits between PCPs and mental health specialists, and the complex implications of pediatric psychotropic polypharmacy.Pharmaceutical Health Outcomes and Policy, Department o