Evaluation of adherence patterns in schizophrenia using electronic monitoring (MEMS®): A six-month post-discharge prospective study.

BACKGROUND: Medication Event Monitoring System (MEMS®) is considered the gold standard for the evaluation of medication adherence, yet few studies have applied this method, especially over long periods of time.

OBJECTIVE: To investigate medication adherence patterns in a sample of post-discharge patients with schizophrenia monitored with MEMS caps during a six-month period.

METHOD: Adherence to antipsychotics was prospectively investigated using MEMS among 68 patients with schizophrenia. Treatment initiation, implementation or whether or not the patient takes his dosing regimen as prescribed, persistence or the length of time between initiation and discontinuation, and treatment discontinuation were used to describe adherence. Persistence over time was described using Kaplan-Meier curves.

RESULTS: After discharge 16% of the patients never initiated treatment. On average 37.3% of patients adhered to treatment in the first 6months. However, a strong decrease in adherence was observed over time (p<0.0001), primarily due by treatment non-persistence. Only half of the patients were persistent at 6weeks, persistence further dropped to 19.0% after 6months. Among persistent patients, implementation was consistent over time with 87.8% of patients taking their medication as prescribed on any given day.

CONCLUSIONS: Dosing profile analysis provides further evidence for the magnitude of non-adherence with antipsychotic prescriptions among post-discharge patients with schizophrenia. Using the high precision of MEMS®, dosing profiles may provide a better understanding of non-adherence patterns and help clinicians determine optimal individualized strategies.