Effects of antipsychotic dose reduction on metabolic syndrome in patients with first episode psychosis treated with a long-acting injectable antipsychotic.

Abstract

Background: The introduction of antipsychotics has been a significant milestone in the treatment of schizophrenia. However, these agents have several important side effects, such as metabolic syndrome. Options to curb these side effects include a change in the treatment option, changes in patients’ lifestyle, and the addition of other medications such as metformin, among others. Thus, this study investigated whether dose reduction of an injectable antipsychotic, flupenthixol decanoate, would result in improvement of metabolic syndrome parameters in a cohort of first-episode schizophrenia patients in South Africa. Methods: The study included 33 participants recruited at the Tygerberg and Stikland Hospitals in the Western Cape Province, South Africa. The metabolic syndrome profiles of all 33 participants were compared at baseline and at point of relapse. All participants were given a monthly dose of an injectable antipsychotic, flupenthixol decanoate, which was gradually reduced until the participant relapsed or was off treatment. Adherence to treatment was guaranteed as all participants had to visit the healthcare facility to receive their injectable. Results: The majority of the participants were colored (75.8%). Most (64%) of the participants were overweight. The mean time to relapse was 39.2 weeks, and by week 32, almost half of the participants had relapsed. A significant change was observed for weight (p = 0.018), waist circumference (p = 0.006) and fasting glucose (p = 0.045). There were no significant changes in the lipid parameters following the antipsychotic dose reduction. Conclusion: Antipsychotic dose reduction resulted in weight loss; however, the majority of patients relapsed with some having important consequences. Further studies are needed to understand the dynamics of treatment discontinuation in schizophrenia patients; however, clinicians should closely monitor patients taking antipsychotics as metabolic syndrome negatively impacts on the patients’ quality of life.