Treatment adherence across different psychiatric disorders: findings from a large patient cohort

Introduction Medication adherence was defined by the WHO as “the extent to which a person’s behavior coincides with the medical advice given” (WHO, 2003). Existing literature indicates that approximately 49% of patients with major psychiatric disorders do not fully adhere to their prescribed psychopharmacological therapy (Colom et al, 2002). Non-adherence can lead to partial therapeutic responses or treatment resistance, increased risk of relapse, re-hospitalization, elevated suicide risk, and overall poorer functioning, thereby compromising the patient-doctor therapeutic relationship (Garcìa et al, 2016). Objectives The aim of the present study was to assess potential differences in terms of clinical features related to adherence to treatment in a large cohort of psychiatric patients of an Italian psychiatric department. Methods The study included 307 psychiatric patients, of any gender or age, diagnosed with unipolar depression (UD), bipolar depression (BD), anxiety disorders (AD), schizophrenic spectrum disorders (SS) or a primary diagnosis of personality disorders (PD), based on DSM-5 criteria. Patients were consecutively recruited from the Department of Psychiatry at Luigi Sacco University Hospital, in Milan. The patient’s adherence to treatment was evaluated using the Clinician Rating Scale (CRS), with a cut-off of ≥ 5 defining adherence subgroups (A+: score ≥ 5; A-: score < 5). Comparative and predictive analysis were performed for the whole sample and the two adherence subgroups. Results Overall, nearly one-third of the whole sample reported suboptimal medication adherence. Specifically, rates were approximately 35.3% and 32.7% for BD and SS, respectively, followed by 30.8% for PD, 28% for AD and, 20.3% for UD (see Figure 1). Patients with A- showed significantly higher current substance abuse (17.8% vs 4.5%, p