Guideline Implementation and Patient-Tailoring Strategies to Improve Medication Adherence for Schizophrenia

Abstract

To determine the effectiveness of an intervention to promote medication adherence. Data were collected for adults with exacerbation of schizophrenia who were treated at one of 6 U.S. Department of Veterans Affairs (VA) Medical Centers (VAMCs) in 3 regional VA networks (Veterans Integrated Service Networks [VISNs]) from March 1999 to October 2000. All 6 VAMCs received a basic guideline implementation strategy for medication management of schizophrenia using usual VA procedures. One VAMC within each VISN was randomly selected to receive an enhanced implementation strategy designed to promote guideline-concordant prescribing by physicians and medication adherence by patients. In the enhanced strategy, a research nurse worked with study participants to identify medication adherence barriers and to develop patient-specific strategies to overcome those barriers. Participants (N = 349) were interviewed at enrollment and 6 months later, using the Structured Clinical Interview for the Positive and Negative Syndrome Scale (PANSS), the Barnes Akathisia Rating Scale, and the Schizophrenia Outcomes Module (SCHIZOM). Medication adherence was measured via subjects' self-report, using the SCHIZOM, and from data abstracted from medical records. Participants were primarily male (94%) and nonwhite (69%, primarily African American) with a mean age of 46 years. Medication adherence at follow-up was modeled using logistic regression, controlling for adherence at baseline, demographic characteristics, PANSS total score, akathisia at baseline, family history of mental illness, and substance abuse. A logistic regression model for adherence at follow-up was significant (likelihood ratio = 52.72, df = 14, p < .0001). Patients enrolled at sites receiving the enhanced intervention were almost twice as likely to be adherent at follow-up. Those who were nonadherent at baseline were significantly less likely to be adherent at follow-up. In addition, adherence at follow-up was significantly greater at 2 of the VA networks as compared to the third network. These data suggest that a patient-centered strategy to identify and overcome barriers to adherence can improve adherence to antipsychotic medications.