The Incidence and Economic Burden of Extrapyramidal Symptoms in Patients with Schizophrenia Treated with Atypical Antipsychotics

Background: Extrapyramidal symptoms (EPS), including movement disorders, tremors, and muscle contractions are common side effects of atypical antipsychotic (AAP) drugs in patients with schizophrenia. This study examined the incidence and burden of EPS in patients with schizophrenia initiating AAPs.

Methods: Patients with schizophrenia initiating AAPs with no prior EPS were identified in the MarketScan Multi-state Medicaid database from 1/1/2012-12/31/2018. Incidence of EPS (identified via ICD-9/ICD-10 diagnoses and medications) was assessed during the 12-month following AAP initiation. Cohorts with and without EPS were defined. Demographics, clinical characteristics, and healthcare resource use and costs over 12 months following the first EPS claim (EPS) or randomly assigned index date (Non-EPS) were assessed.

Results: A total of 11,642 patients with schizophrenia were identified; 19.7% developed EPS in the 12-month following AAP initiation (incidence: 23.6/100 person-years). EPS and Non-EPS cohorts included 2,295 (mean age 38, 61% male, CCI 0.6) and 5,607 (mean age 39, 57% male, CCI 0.7) patients, respectively. Over the 12-month post-index period, EPS cohort had significantly higher rates of all-cause (30.2% vs. 24.6%, p<0.001) and schizophrenia-related hospitalizations (22.5% vs. 12.9%, p<0.001) and schizophrenia-related emergency room visits (25.5% vs. 16.7%, p<0.001) compared to Non-EPS cohort. All-cause ($25,911 vs. $21,550, p<0.001) and schizophrenia-related healthcare costs ($12,134 vs. $6,230, p<0.001) were significantly higher in EPS vs. Non-EPS cohort.

Conclusions: In the 12 months following AAP initiation, approximately 20% of schizophrenia patients developed EPS, which was associated with increased healthcare resource utilization and costs. Treatment options that minimize EPS may reduce the economic burden of schizophrenia.