Sleep apnea may predict postoperative delirium
More than half of a cohort of elderly patients with obstructive sleep apnea developed postoperative delirium after knee surgery, according to recent results.
Researchers from several sites in the United States aimed to explore effective treatment strategies for postoperative delirium in the elderly. The causative factors of this common complication may be multiple and varied and may be linked to increased morbidity and mortality, and subsequent cognitive issues.
Eligible participants in the prospective study were aged 65 years or older and were undergoing elective knee arthroplasty. They were assessed on days 2 and 3 post-surgery to determine whether they met criteria for Diagnostic and Statistical Manual of Mental Disorders-IV delirium.
Dementia, mini-mental state exam scores less than 24, delirium, clinically significant central nervous system/neurologic disorder, current alcoholism, or any serious psychiatric disorder comprised the exclusion criteria.
Using data from medical charts and polysomnography records, investigators evaluated patients for pre-existing medical conditions and for the occurrence of obstructive sleep apnea.
The final analysis included 106 patients. Twenty-five percent of those patients developed postoperative delirium.
There were 15 patients with obstructive sleep apnea. While postoperative delirium occurred in 53% of those patients, it occurred in just 20% of the patients without obstructive sleep apnea (P=.0123; OR=4.3).
Multivariate analysis results indicated that obstructive sleep apnea was the only statistically significant predictor of postsurgery delirium.