Medication-Adherent First-Episode Psychosis Patients Also Relapse: Why?

Abstract

Poor adherence to medication is a major determinant of relapse following treatment of first-episode psychosis (FEP). However, medication-adherent patients also relapse. We examined what factors influence the risk of relapse after controlling for adherence. We selected a sample of fully adherent patients (n = 65) who had achieved remission at one point. We then compared patients who relapsed, using 2 different definitions of relapse, to those who did not relapse by 12 months on age, sex, premorbid adjustment, duration of untreated psychosis, length of prodrome, and substance abuse. Among the 65 medication-adherent patients in remission, 9 (14%) relapsed according to criteria for relapse requiring a change in medication. These patients differed from those who remained in remission only in the pattern of premorbid adjustment (greater proportion with deteriorating pattern), although this was not independent of other variables. No differences were found on any other variable. Using a more commonly used metric for relapse, based on symptom ratings alone, an additional 14 (21.5%) patients relapsed. Substance abuse significantly predicted relapse, with substance abusers having more than 25 times the odds of relapsing by 12 months (OR 25.6; 95% CI 2.4 to 278.1, P = 0.008). Using a more conservative definition of relapse in this adherent-to-medication population, we find a very low rate of relapse associated, at least partially, with poor premorbid adjustment. As substance abuse was a significant predictor of symptomatic relapse, this would suggest that there should be a greater emphasis on interventions focused on reducing substance abuse in FEP.