Abstract
BACKGROUND: Psychotropic medications are critical in managing severe mental illnesses (SMI) such as schizophrenia, major depressive disorder (MDD) and bipolar disorder. However, these treatments often lead to adverse side effects that can impair patients' quality of life (QoL) and affect treatment adherence. OBJECTIVE: This study aims to investigate the specific side effects of psychotropic treatments that contribute to a decline in QoL among patients with SMI, independently of treatment adherence. METHODS: We conducted a cross-sectional study with 1248 patients diagnosed with SMI, recruited from a university psychiatric unit in Marseille, France. QoL was assessed using the Schizophrenia Quality of Life Scale (SQoL-18), and side effects were measured using the UKU Side Effect Rating Scale. Treatment adherence was evaluated using the Medication Adherence Rating Scale (MARS). Statistical analyses included Pearson correlations and multiple linear regression models to identify predictors of QoL. RESULTS: The study found that side effects, as identified by the UKU scores, could significantly predict a reduction in QoL across multiple domains, including multiple dimensions of QoL and the overall QoL index, independent of treatment adherence. Patients on antipsychotics and benzodiazepines reported higher levels of adverse side effects, which correlated with lower QoL scores. An increase in the number of psychotropic treatment classes was also associated with a significant decline in QoL (p < 0.001). CONCLUSION: Managing psychic side effects and minimising polypharmacy are critical to improving QoL in patients with SMI. Clinicians should consider these factors when developing personalised treatment strategies to enhance patient outcomes.