Eighty-one percent of hospital patients are at high risk for obstructive sleep apnea, a Loyola University Health System study has found.

The findings suggest that hospitals should consider giving patients a five-minute screening test to identify those who are at high risk.

Sleep specialist Dr. Sunita Kumar and colleagues administered an eight-question obstructive sleep apnea screening questionnaire known as STOP-BANG to patients during a single day at Loyola University Hospital. Patients were excluded if they were on a breathing tube, on sedatives or had altered mental status.

Of the 195 patients surveyed, 157 (80.5 percent) were at high risk for obstructive sleep apnea, meaning they answered "Yes" to at least three questions on the STOP-BANG questionnaire.

Kumar reported results during Chest 2010, the annual meeting of the American College of Chest Physicians in Vancouver.

During obstructive sleep apnea, breathing pauses as often as 30 times an hour, causing poor sleep quality and excessive daytime sleepiness. About 5 percent of the general population is reported to have obstructive sleep apnea. The prevalence is likely higher due to increasing obesity.

There are little data on the prevalence of obstructive sleep apnea in hospitalized patients. Obstructive sleep apnea can increase the risk of high blood pressure, heart attack, stroke, obesity, diabetes, heart failure and arrhythmias (irregular heartbeats).

While 157 patients in the study were at high risk for apnea, only 41 had been evaluated in an overnight sleep lab. Of those 41 patients, 31 had been diagnosed with obstructive sleep apnea. But only 18 were being treated, either with a CPAP breathing mask (17 patients) or surgery (1 patient).

"Undiagnosed obstructive sleep apnea may be associated with increased risk of complications in hospitalized patients," Kumar and colleagues reported. "Screening and evaluation for obstructive sleep apnea in high-risk patients should be considered as it may help reduce the burden of undiagnosed obstructive sleep apnea."

Kumar is an assistant professor in the Division of Pulmonary and Critical Care Medicine at Loyola University Chicago Stritch School of Medicine. Her co-authors, all Loyola fellows in pulmonary and critical care medicine, are Dr. David McElligott, Dr. Amit Goyal, Dr. Matthew Baugh and Dr. Ramona Ionita.

The STOP-BANG questionnaire consists of eight questions:

1. Do you Snore loudly?

2. Are you Tired or sleepy during the day?

3. Has anyone Observed you stop breathing during sleep?

4. Do you have high blood Pressure?

5. Do you have a Body mass index higher than 35. (Depending on height, this means being roughly 65 or 70 pounds or more overweight).

6. Is your Age older than 50?

7. Do you have a Neck circumference greater than 40 cm. (15.7 in.)?

8. Is your Gender male?

A score of 3 or more yes answers is considered a high risk for obstructive sleep apnea.