Predictive factors for antipsychotic treatment adherence among first-episode psychosis patients in the first year after remission
Summary
Abstract
Background: Adherence rates to antipsychotic drugs in schizophrenia are low, while good adherence is
important for achieving and maintaining remission. In patients with a ‘First Episode of Psychosis’ (FEP),
early medication adherence can influence the further course of the illness. Identification of risk factors for
non-adherence to antipsychotics in patients with an FEP in the first year after remission could prove useful.
Methods: This study was conducted with patients aged 16 to 55 years old, using antipsychotic medication,
and in symptomatic remission of their first psychotic episode for 3-6 months. Medication adherence was
determined with the Medication Possession Ratio (MPR) and validated with self-reported adherence rates.
Covariate adjustment was performed to determine the influence of overlapping prescriptions on the MPR.
The relationship between several patient- and environment-related factors with treatment adherence was
assessed with linear regression.
Results: A total of 260 patients were included in the MPR calculation, of which 88,8% had a good treatment
adherence. The MPR had a very weak correlation with the self-reported adherence rates (p = 0.005). Side
effects (p = 0.013) were positively associated with treatment adherence while patients experiencing more
self-stigma were less adherent (p = 0.030). Overlapping prescriptions accounted for 25% of the variance in
the MPR. After covariate adjustment, only the duration of psychosis was associated with treatment
adherence (p = 0.001).
Conclusion: The MPR is sensitive to prescribing behavior, therefore correction for overlapping
prescriptions is advised. Intervention strategies focused on lowering self-stigma among FEP patients could
improve their adherence rates