Treatment adherence in schizophrenia: A patient-level meta-analysis of combined CATIE and EUFEST studies

Abstract

The Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) obtained a sample of 1493 chronic schizophrenia patients. The European First Episode Schizophrenia Trial (EUFEST) studied a sample of 498 patients. We have combined these two samples to study the predictors and correlates of adherence to treatment. Here we report on adherence to pharmacological treatment at the six and twelve month assessments of these trials with a combined subsample of 1154 schizophrenia patients. Individual patients’ data were used for analyses. We used logistic regression to examine the effects of substance use, akathisia, parkinsonism, dyskinesia, hostility, and insight on pharmacological adherence. The results showed that reduced adherence to pharmacological treatment was associated with substance use (p=0.0003), higher levels of hostility (p=0.0002), and impaired insight (p<0.0001). Furthermore, poor adherence to study medication was associated with earlier discontinuation in the combined data. The clinical implications of the results point to the importance of routine assessments and interventions to address patients’ insight and comorbid substance use and the establishment of therapeutic alliance.

Real-world adherence and economic outcomes associated with paliperidone palmitate versus oral atypical antipsychotics in schizophrenia patients with substance-related disorders using Medicaid benefits

“…In a recent pooled analysis of two randomized trials (total n = 1154), substance use was associated with reduced adherence which sequentially predicted earlier discontinuation [23]. Indeed in the current analysis, antipsychotic adherence rates (∼30-40%) in patients with co-occurring substance-related disorders, were lower than those observed among a recently studied population with and without substance-related disorders treated with PP1M following a recent hospitalization (51%) [11].…”

Effect of a Telephone Intervention upon Medication Adherence and Related Outcomes in Outpatients with Schizophrenia Spectrum Disorders (SSDs)

“…These adherence percentages are lower than the average nonadherence rate of 60% reported by others [2,4]. Compared to our prior work [15], average pill count psychiatric medication adherence in this study was lower for both experimentals and controls; average nonpsychiatric medication adherence in this study was higher for both groups.…”

“…Poor psychiatric medication adherence results in increased illness episodes associated with re-hospitalizations, longer time to remission and suicide attempts [2], all of which contribute to the exceedingly high personal and societal cost of SSDs. While the efficacy of antipsychotic medication for SSD maintenance is well documented [3], rates of nonadherence to antipsychotic medications in persons with SSDs range from 11-80% with average nonadherence exceeding 60% [4].…”

Adherencia a la medicación antipsicótica en pacientes indígenas con esquizofrenia

“…[17][18][19][20] Estudios previos han encontrado que pacientes varones, jóvenes, con bajo nivel socioeconómico, pertenecientes a una minoría, con pobre funcionamiento social y con dificultades en el establecimiento de una adecuada alianza terapéutica presentan mayores dificultades para lograr adherencia en el tratamiento. 8,21 Se ha observado de igual forma que el contexto cultural y la etnicidad también tienen una influencia importante. Así, pacientes afro-americanos y mexicanos-americanos mostraron más baja adherencia (19 días y 18 días menos, respectivamente) que pacientes blancos en un estudio realizado en Texas.…”