A Rhode Island Hospital researcher has found that the majority of bariatric surgery patients being treated for obesity have clinically significant obstructive sleep apnea (OSA), but report fewer symptoms than other sleep disorders patients. The study by Katherine M. Sharkey, M.D., Ph.D., of the department of medicine, division of pulmonary, critical care and sleep medicine at Rhode Island Hospital, and University Medicine, is published online in advance of print in the journal Sleep and Breathing.
"Patients with obstructive sleep apnea frequently complain of sleepiness during the daytime, loss of motivation and interest in activities, as well as poor concentration and memory recall," Sharkey said. "However, we found that while the vast majority of patients considering bariatric surgery for treatment of obesity have clinically significant OSA, they report fewer symptoms, and may be attributing daytime napping and decreased functioning to something other than a sleep disorder."
Obstructive sleep apnea is a condition in which the airway becomes narrowed or floppy during sleep, decreasing the flow of air and therefore interrupting breathing during sleep. OSA can be caused by many factors, including obesity. In fact, obese patients have a high prevalence of this sleep disorder, and ultimately are at a higher risk for numerous negative health outcomes including congestive heart failure, coronary artery disease, hypertension and stroke, as well as post-operative respiratory complications and increased perioperative morbidity and mortality following bariatric surgery.
The study identified 269 patients (239 women) who had sleep evaluations prior to bariatric surgery. The patients underwent overnight polysomnography and completed both the Epworth Sleepiness Scale (a questionnaire that asks about a person's tendency to fall asleep) and the Functional Outcomes of Sleep Questionnaire (a questionnaire that asks about how a person's life is limited because of sleep problems). Nearly 60 percent of the study sample had moderate or severe OSA that had not been diagnosed prior to the patients' evaluation in anticipation of bariatric surgery. Despite the high prevalence of sleep apnea, the bariatric patients reported significantly fewer symptoms than typical OSA patients.
"The lack of symptoms of sleep apnea in this population means that we must be even more vigilant in identifying sleep apnea prior to bariatric surgery in order to reduce the risk of complications," Sharkey said.