Neuropeptide Y levels, social functionality, and cognitive insight in patients with schizophrenia in symptomatic remission: A case-control study

Abstract

Objective This case-control study aimed to investigate serum neuropeptide Y (NPY) levels in patients with schizophrenia in symptomatic remission and to examine their relationship with social functioning and cognitive insight. Methods Forty patients with schizophrenia in symptomatic remission and 40 healthy controls, matched for age, gender, and educational level, were included. Social functioning was assessed using the Personal and Social Performance (PSP) scale, and cognitive insight was evaluated with the Beck Cognitive Insight Scale (BCIS). Serum NPY levels were measured using enzyme-linked immunosorbent assay (ELISA). Correlation, regression, and receiver operating characteristic (ROC) analyses were performed. Results Serum NPY levels were significantly lower in patients with schizophrenia compared to healthy controls (231.4 ± 457.8 ng/L vs 683.0 ± 1097.8 ng/L, p < 0.001). No significant correlations were found between NPY levels and social functioning or cognitive insight. An NPY cut-off value of 125.2 ng/L predicted schizophrenia with 67.5% sensitivity and specificity (AUC = 72.6). Regression analysis demonstrated that clinical insight (PANSS G12 score) was significantly associated with social functioning (β = −11.368, p < 0.05). Conclusion Patients with schizophrenia in symptomatic remission exhibited significantly lower serum NPY levels than healthy controls. However, NPY levels were not associated with social functioning or cognitive insight. These findings suggest that NPY may be a potential biomarker for schizophrenia, although its role in functionality and insight warrants further investigation.