PMH40 - Non-Adherence to Antipsychotics and Disease Comorbidity: A Double Whammy in Schizophrenia Management

Abstract

To determine the impact of non-adherence to anti-psychotic (AP) drugs and disease comorbidity on healthcare utilization and health status in schizophrenia. A retrospective, cross sectional research data was obtained from Medical Expenditure Panel Surveys (MEPS, 2010-2014). Proportion of Days Covered (PDC) measure of adherence was used to identify and classify individuals as adherent (PDC ≥ 80%) or non-adherent (PDC < 80%). Charlson Comorbidity Index(CCI) scores were used to identify disease comorbidity in schizophrenia. Effects of key study variables on medication non-adherence were observed. Group comparisons using Student’s t-test were also performed for utilization in two groups—adherent vs nonadherent & comorbid vs non-comorbid populations. The HRQoL was measured in terms of Physical Component Summary (PCS) and Mental Component Summary (MCS) scores using Short Form-12, along with Kessler Index (K6) score for psychological distress. 71% of about 1.2 million people who had schizophrenia reported a PDC score of < 80%, representing significant non-adherence concerns. A logistic regression analysis showed that women (OR=3.594, 95% CI 1.33-11.40, p=0.030), married individuals (OR=0.065, 95%CI 0.004-1.11,p=0.0049) and persons with higher education (OR=20.85,95%CI 3.91-111.09,p=0.0005) were more likely to be non-adherent to AP and also reported greater outpatient visits (0.68 vs 1.92,p<0.0001) and office based visits (10.95 vs 18.21,p<0.0001), compared to adherent persons. Additionally, individuals with comorbidity had greater inpatient visits (0.39 vs 0.76,p<0.0001), office-based visits (13.39 vs 19.34, p<0.0001) and ER visits (0.39 vs 1.41, p<0.0001) compared to those without comorbidity. Higher HRQoL scores on both the SF-12 components (MCS: 53.55 vs 32.69, p=0.022; PCS: 38.57 vs 37.35, p=0.7215) and the Kessler Index score of psychological distress (K6: 7.36 vs 7.16, p<0.8916) were observed for the adherent group. Greater medical care resources are utilized by schizophrenia individuals that are non-adherent to anti-psychotic medications and also diagnosed with comorbidities than those without such problems.