Study of correlation of serum IL-6 levels and cognitive dysfunction among patients with obstructive sleep apnoea syndrome / 中国医师杂志

ABSTRACT

Objective To investigate the relationship of serum IL-6 levels with cognitive dysfunction among patients with obstructive sleep apnoea syndrome (OSAS).Methods Patients diagnosed with OSAS by polysomnography (PSG) received assessment of cognitive function with Montreal Congnitive Assessment (MoCA).According to the result of MoCA assessment,patients were divided into two groups,without cognitive dysfunction group (n =47) and with cognitive dysfunction group (n =55);30 health volunteers were used as control.Serum IL-6 levels were detected by enzyme-linked immunosorbent assay (ELISA) in three groups;according to the apnea hypopnea index (AHI),OSAS patients with cognitive dysfunction were divided into three groups,light group (n =15),moderate group (n =16),and severe group (n =24),and differences in MoCA scores and serum IL-6 levels were analyzed among three groups.The correlation of serum IL-6 levels and MoCA scores were analyzed in OSAS patients with cognitive dysfunction.Results Serum levels of IL-6 in OSAS patients with cognitive dysfunction [(197.3 ± 72.58) pg/ ml] were significantly increased than those without cognitive dysfunction [(155 ± 39.3)pg/ml] as well as health control [(87.39 ±33.44)pg/ml] (P ＜0.01).For OSAS patients with cognitive dysfunction,MoCA scores were decreased and the level of serum IL-6 was increased among patients with poor AHI grade,with statistically significant difference.Pearson correlation analysis showed serum IL-6 levels were significantly negatively correlated with MoCA scores among OSAS patients with cognitive dysfunction (r =-0.65,P ＜ 0.01).Conclusions Serum levels of IL-6 in OSAS patients with cognitive dysfunction were significandy increased and correlated with the cognitive dysfunction.OSAS patients with cognitive dysfunction experiencing sever AHI grade have more serious cognitive dysfunction and the higher serum levels of IL-6.