Obstructive Sleep Apnea and Postoperative Cognitive Decline in Non-Cardiac Surgery: A Prospective Cohort Study

Background:: Obstructive sleep apnea may be linked to postoperative cognitive decline. We conducted a prospective observational study to determine whether the severity of sleep apnea is associated with postoperative cognitive decline following non-cardiac surgery. Methods:: Adult patients undergoing elective non-cardiac surgery were enrolled in the study. A series of cognitive tests, including the verbal fluency test, digit symbol substitution test, and word list recall, were used to compare cognitive function before and after surgery. The Telephone Interview for Cognitive Status assessed long-term cognitive function at 30 and 90 days post-surgery. Results:: In total, 65 patients were included in the analysis, with a mean age of 63.7 years (SD = 7.4). The overall incidence of postoperative cognitive decline within the first 2 days after surgery was 18.5%. Our study found that patients with moderate to severe obstructive sleep apnea did not have a higher risk of postoperative cognitive decline compared to those with no or mild obstructive sleep apnea (p = 0.339). However, a history of depression emerged as an independent risk factor for postoperative cognitive decline (p = 0.045). Furthermore, there was no significant difference in cognitive function between the obstructive sleep apnea groups at 30 and 90 days after surgery. Conclusions:: Our study indicates no clear association between the severity of obstructive sleep apnea and postoperative cognitive decline within 90 days after surgery. Instead, we identified preoperative depression as a significant risk factor for postoperative cognitive decline. Therefore, it is important to exercise caution when managing patients with depression.