Guideline-Concordant Antipsychotic Use and Mortality in Schizophrenia

Abstract

To determine if care concordant with 2009 Schizophrenia Patient Outcomes Research Team (PORT) pharmacological recommendations for schizophrenia is associated with decreased mortality. We conducted a retrospective cohort study of adult Maryland Medicaid beneficiaries with schizophrenia and any antipsychotic use from 1994 to 2004 (N = 2132). We used Medicaid pharmacy data to measure annual and average antipsychotic continuity, to calculate chlorpromazine (CPZ) dosing equivalents, and to examine anti-Parkinson medication use. Cox proportional hazards regression models were used to examine the relationship between antipsychotic continuity, antipsychotic dosing, and anti-Parkinson medication use and mortality. Annual antipsychotic continuity was associated with decreased mortality. Among patients with annual continuity greater than or equal to 90%, the hazard ratio [HR] for mortality was 0.75 (95% confidence interval [CI] 0.57-0.99) compared with patients with annual medication possession ratios (MPRs) of less than 10%. The HRs for mortality associated with continuous annual and average antipsychotic continuity were 0.75 (95% CI 0.58-0.98) and 0.84 (95% CI 0.58-1.21), respectively. Among users of first-generation antipsychotics, doses greater than or equal to 1500 CPZ dosing equivalents were associated with increased risk of mortality (HR 1.88, 95% CI 1.10-3.21), and use of anti-Parkinson medication was associated with decreased risk of mortality (HR 0.72, 95% CI 0.55-0.95). Mental health visits were also associated with decreased mortality (HR 0.96, 95% CI 0.93-0.98). Adherence to PORT pharmacological guidelines is associated with reduced mortality among patients with schizophrenia. Adoption of outcomes monitoring systems and innovative service delivery programs to improve adherence to the PORT guidelines should be considered.