“No Cognitive-Enhancing Effect of GLP-1 Receptor Agonism in Antipsychotic-Treated, Obese Patients With Schizophrenia”, 2017-03-05 ():
Objective: Schizophrenia is associated with profound cognitive and psychosocial impairments. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are used for diabetes and obesity treatment, and animal studies have indicated cognitive-enhancing effects. In this investigator-initiated, double-blind, randomized, placebo-controlled trial, we tested non-metabolic effects of exenatide once-weekly (Bydureon™) in obese, antipsychotic-treated patients with schizophrenia spectrum disorder.
Method: Before and after 3 months of exenatide (n = 20) or placebo (n = 20) treatment, patients were assessed with the following: Brief Assessment of Cognition in Schizophrenia (BACS), Rey–Osterreith complex figure test (REY), Short-Form Health Survey (SF-36), Personal and Social Performance Scale (PSP) and the Positive and Negative Syndrome Scale (PANSS). We used BACS composite score as the main outcome measure.
Results: Repeated measures analysis of variance on BACS composite score showed statistically-significant effect of ‘Time’ (p < 0.001), no effect of ‘Group’ (p = 0.64) and no ‘Time × Group’ interaction (p = 0.77). For REY, SF-36, PSP and PANSS, only statistically-significant ‘Time’ effects were found.
Conclusion: The non-statistically-significant results of this first clinical trial exploring non-metabolic effects of a long-acting GLP-1RA in patients with schizophrenia could reflect a general problem of translating cognitive-enhancing effects of GLP-1RAs from animals to humans or be explained by factors specifically related to schizophrenia spectrum patients with obesity such as antipsychotic treatment.