Objective To investigate the correlation of serum insulin-like growth factor-1 (IGF-1), neural cell adhesion molecule (NCAM) levels with clinical symptoms in patients with chronic schizophrenia and their diagnostic value for cognitive impairment.

Methods A total of 100 patients with chronic schizophrenia who admitted to Kailuan General Hospital from May 2017 to November 2018 were included in study group, and were divided into cognitive impairment group (n=46) and normal cognition group (n=54) according to the Chinese version of Montreal Cognitive Assessment (MoCA) Scale. Another 100 healthy subjects were included in control group. Serum IGF-1 and NCAM levels, clinical symptomspositive and negative symptom scale (PANSS) positive symptoms, negative symptoms, general psychopathological symptom scores were observed and compared between the groups. Correlation of serum IGF-1 as well as NCAM levels with clinical symptoms and their diagnostic value for cognitiveimpairment in the study group.

Results The levels of IGF-1 and NCAM in the study group were significantly lower than those in the control group (P < 0.05). The levels of IGF-1 and NCAM in the cognitive impairment group were significantly lower, and the PANSS score was significantly higher than that in the normal cognition group (P < 0.05). The levels of IGF-1 and NCAM in the study group were negatively correlated with the PANSS positive symptoms, negative symptoms, general psychopathological symptom scores and total scores (P < 0.05); the sensitivity of serum IGF-1, NCAM and their combination in the diagnosis of cognitive impairment was 95.65%, 89.13% and 89.13%, respectively, the specificity was 81.48%, 88.89% and 98.15%, respectively, and the area under the curve (AUC) was 0.936, 0.947 and 0.955, respectively.

Conclusion The serum levels of IGF-1 and NCAM in patients with chronic schizophrenia are negatively correlated with the severity of clinical symptoms, and they have important diagnostic significance for the changes of cognitive function in patients.