Medication compliance and comorbid substance abuse in schizophrenia: impact on community survival 4 years after a relapse.

This prospective study examined the effect of medication compliance and substance abuse on 4 year outcome in 99 patients following a relapse of schizophrenia. Univariate survival analysis revealed longer community tenure in patients if they were over the age of 35 years, not admitted 2 years prior to the index episode, remained medication compliant and did not abuse substances during the follow-up interval. Comparisons between patients grouped according to medication compliance and current substance abuse indicated that those patients who regularly took their medication but also abused substances were readmitted to hospital sooner (median survival, 10 months) compared to compliant patients who did not use substances (37 months). For noncompliant patients, time to first readmission was shorter for patients with a dual diagnosis (5 months) compared to patients with a singular diagnosis of schizophrenia (10 months). Over the 4 year period, noncompliant patients with a dual diagnosis (n=28) accounted for 57% of all hospital readmissions for the cohort and averaged 1.5 admissions per patient year. These data indicate that much of the benefit that antipsychotic medication has on increasing community survival is reduced by substance abuse. This interval is further reduced in patients who are both substance abusers and noncompliant with medication resulting in a revolving door situation of frequent hospital admissions. Integrated treatment programs which address these issues are likely to reduce the need for hospital readmission in patients with a dual diagnosis.