M125. DISEASE PREVALENCE, COMORBID CONDITIONS, AND MEDICATION UTILIZATION AMONG PATIENTS WITH SCHIZOPHRENIA IN THE UNITED STATES
Authors: Roy Brittany , Li Jianheng , Lally Cathy , Shah Ankitaben , Bloomgren Gary , Wenten Made 
Published: May 2020

Background

The comorbid medical and psychiatric burden for individuals with schizophrenia in the United States is substantial compared with the general population. This study sourced the IBM® MarketScan® Research Databases to examine disease prevalence, comorbid conditions, and drug treatments in a large population of commercial- or Medicaid-insured individuals with schizophrenia in the United States to characterize this patient population.

Methods

A retrospective cross-sectional claims analysis from the IBM® MarketScan® Commercial and Medicare Supplemental Databases and the Multi-state Medicaid Database from January 1, 2009 to June 30, 2016 was conducted. Individuals with dual coverage for commercial and Medicare Supplemental were included within the commercial analysis. Schizophrenia cases were defined by ≥1 diagnostic claim (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM]/ICD-10-CM) for schizophrenia anytime during the study period. Comorbidities were assessed by ≥1 ICD-9-CM/ICD-10-CM diagnosis code, grouped into clinically meaningful categories according to the Clinical Classifications Software (CCS) level 2 categories. For the comorbidity analysis, within each database, schizophrenia cases were matched with controls along several demographic characteristics. Case-control comorbidity comparisons were performed using prevalence rate ratios (PRRs) and 95% confidence intervals. Medication exposure was assessed for cases only within each database and was based on ≥1 National Drug Code (NDC) occurring in the outpatient setting grouped by Redbook classification.

Results

Schizophrenia prevalence was 0.99% in Medicaid-insured patients and 0.11% in those with commercial insurance. In both commercial and Medicaid databases, the prevalence of comorbidities was higher among schizophrenia cases as compared with controls in approximately ≥80% of the CCS level 2 categories assessed. Of the top 5 categories of comorbidities across databases for schizophrenia cases, those in common were mood disorders, anxiety disorders, other connective tissue disease, and cardiovascular disease. The comorbidities with the highest case-control PRR point estimates across databases included personality disorders, suicide and intentional self-inflicted injury, and impulse control disorders. Antipsychotics, antidepressants, and analgesics/antipyretics–opiate agonists were the most commonly prescribed medications for schizophrenia cases across databases. Risperidone, quetiapine, aripiprazole, and olanzapine were the top 4 antipsychotics prescribed across both databases. The fifth most commonly prescribed antipsychotics were ziprasidone and haloperidol in the commercial and Medicaid databases, respectively.

Discussion

This large-scale database analysis confirmed the burden of medical and psychiatric comorbidities in patients with schizophrenia compared with controls and provided additional insight on treatment approaches in these patients. Understanding the comorbidities affecting this patient population in comparison with the general population highlights the importance of integrated medical and psychiatric care.