Correlation between preoperative sleep disorders and postoperative delayed neurocognitive recovery in elderly patients.

Abstract

Perioperative neurocognitive disorders (PND) is one of the important factors affecting the recovery of the elderly after surgery, and sleep disorders are also one of the common diseases of the elderly. Previous studies have shown that the quality of postoperative sleep may be factor affecting postoperative cognitive function, but there are few studies on the relationship between preoperative sleep disorders and postoperative cognitive dysfunction. This study aims to explore the relationship between preoperative sleep disorders and postoperative delayed neurocognitive recovery in elderly patients, and provide references for improving the prognosis and quality of life of patients. This study was porformed as a prospective cohort study. Elderly patients (age≥65 years old) underwent elective non-cardiac surgery at Xiangya Hospital of Central South University from October 2019 to January 2020 were selected and interviewed 1 day before the operation. The Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment Scale (MoCA) were used to assess the patient's baseline cognitive status. Patients with preoperative MMSE scores of less than 24 points were excluded. For patients meeting the criteria of inclusion, Pittsburgh Sleep Quality Index (PSQI) scale was used to evaluate the patients, and the patients were divided into a sleep disorder group and a non-sleep disorder group according to the score. General data of patients were collected and intraoperative data were recorded, such as duration of surgery, anesthetic time, surgical site, intraoperative fluid input, intraoperative blood product input, intraoperative blood loss and drug use. On consecutive 5 days after surgery, Numerical Rating Scale (NRS) was used to evaluate the sleep of the previous night and the pain of the day, which were recorded as sleep NRS score and pain NRS score; Confusion Assessment Method for ICU (CAM-ICU) scale and Confusion Assessment Method (CAM) scale were used to assess the occurrence of delirium. On the 7th day after the operation, the MMSE and MoCA scales were used to evaluate cognitive function of patients. We compared the incidence of postoperative complications, the number of deaths, the number of unplanned ICU patients, the number of unplanned secondary operations, etc between the 2 groups. The baseline and prognosis of the 2 groups of patients were analyzed by univariate and multivariate logistics to analyze their correlation. A total of 105 patients were collected in this study, including 32 patients in the sleep disorder group and 73 patients in the non-sleep disorder group. The general information of the 2 groups, such as age, gender, body mass index, and surgery site, were not statistically significant (all P>0.05). There was no statistically significant difference in the operation time, intraoperative bleeding, the number of delirium, and sleep NRS score at 5 days after operation between the 2 groups (all P>0.05). The incidence of unplanned second surgery after surgery and the NRS pain score on the first day in the sleep disorder group were significantly higher than those in the non-sleep disorder group (P=0.002, P=0.045, respectively). A total of 20 patients (19%) in the 2 groups had postoperative delayed neurocognitive recovery on the 7th day after surgery. Among them, 11 patients (34.4%) in the sleep disorder group, 9 patients (12.3%) in the non-sleep disorder group. The incidence of delayed neurocognitive recovery in the sleep disorder group was significantly higher than that in the non-sleep disorder group (P=0.008). The incidence of postoperative infection in the sleep disorder group was also higher than that in the non-sleep disorder group (P=0.020). After controlling for the confounding factors, preoperative sleep disorders were still independently associated with postoperative delayed neurocognitive recovery (OR=3.330, 95% CI 1.063-10.431, P=0.039). Preoperative sleep disorders can increase the risk of delayed neurocognitive function recovery in elderly patients. Active treatment of preoperative sleep disorders may improve perioperative neurocognitive function in elderly patients.