CLINICAL AND PSYCHOPATHOLOGICAL CORRELATES OF TREATMENT WITH LONG-ACTING INJECTABLE ANTIPSYCHOTICS IN PATIENTS WITH PSYCHOSIS: AN OBSERVATIONAL COMPARATIVE STUDY

INTRODUCTION and AIM OF THE STUDY Antipsychotic therapy significantly reduces the risk of relapse in patients with schizophrenia and other psychotic disorders. However, oral therapy is associated with rates of non-adherence of 50-75% . Long-acting injectable antipsychotics (LAI) should offer better efficacy and tolerability due to improved adherence and more stable pharmacokinetics. The aim of this study is the evaluation of clinical and psychopathological correlates of LAI treatment, as compared with the oral antipsychotic one, in a sample of patients suffering from Schizophrenia Spectrum Disorders. MATERIALS and METHODS We conducted a cross-sectional study, drawn up according to the STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) Statement – Checklist. We selected a random sample of clinically stable patients with a diagnosis of DSM-5 Schizophrenia Spectrum Disorder, enrolled from a local outpatient service or the Psychiatric Ward of ASST San Gerardo Hospital of Monza. We collected relevant information on socio-demographic, clinical, and psychopathological, and treatment-related variables. Statistical analyses were performed using Stata version 13.0 SE. We carried out univariate analyses, as well as a logistic regression model, controlling for age and sex, to identify characteristics associated with a LAI treatment. RESULTS We recruited 57 subjects (15 inpatients and 42 outpatients) suffering from Schizophrenia Spectrum Disorders. Among these, 45.6% (n=26) had a treatment with LAI. Univariate analysis have shown a significant association of LAI with unemployment, comorbid personality disorder, and lifetime involuntary treatment. Relevant logistic regression model confirmed the association of LAI treatment with unemployment and lifetime involuntary treatment, but not with a co-occurring personality disorder. Finally, patients treated with LAI were less likely to be treated with an additional oral antipsychotic. DISCUSSION and CONCLUSIONS This observational study has shown that unemployed patients and those with lifetime involuntary treatments were more likely to receive a treatment with LAI. These findings seem coherent with the hypothesis that a treatment with LAI is more often used for individuals requiring higher clinical and psychosocial support. LAI treatment could be a useful option, especially in an early phase of disease, to improve antipsychotic adherence and to prevent clinical relapses. Furthermore, the use of LAI might simplify the treatment for patients with psychosis, reducing the need of an additional oral antipsychotic. Results of this study should be interpreted with caution, due the small sample size limiting the statistical power, as well as the cross-sectional design, that did not allow causal inferences about the direction of the relationship between LAI and clinical correlates.