(RxWiki News) There are many known factors that increase the risk of developing diabetes. New research may be adding one sleep disorder to that list.
A recent study found that people with sleep apnea were at increased risk for developing diabetes.
The researchers discovered that the more severe the case of sleep apnea was, the higher the risk of diabetes.
"Discuss diabetes risk with your doctor if you have sleep apnea."
The lead author of this study was Tetyana Kendzerska, MD, PhD, from the Institute of Health Policy at the University of Toronto in Toronto, Ontario, Canada.
The study included 8,678 adults who underwent a sleep study for suspected obstructive sleep apnea at St. Michael’s Hospital in Toronto between September 1, 1994 and December 31, 2010.
Obstructive sleep apnea is a condition in which a person’s airway becomes blocked while they are sleeping, keeping them from breathing at their full capacity.
None of the people in this study had any previous history of diabetes. Sixty-two percent of participants were male, and the average age was 48 years old.
The severity of the participants’ sleep apnea was evaluated using the apnea-hypopnea index (AHI), which measures how many times a person partially or completely stops breathing per hour of sleep.
The participants were considered to not have sleep apnea if they had less than 5 AHI, to have mild sleep apnea is they had 5 to 14.9 AHI, to have moderate sleep apnea if they had 15 to 30 AHI, and to have severe sleep apnea if they had more than 30 AHI.
The researchers conducted follow-up through May 2011 for an average of 67 months.
The findings showed that 1,017 (12 percent) of the participants developed diabetes over the course of the study. The five-year incidence of diabetes was 9 percent.
After adjusting for known diabetes risk factors, such as age, sex, body mass index (height to weight ratio), neck size, smoking, income status and other co-occurring conditions, Dr. Kendzerska and team determined that the participants with severe sleep apnea were 30 percent more likely to develop diabetes than those who did not have sleep apnea.
Those who had mild or moderate sleep apnea were 23 percent more likely to develop diabetes than those who did not have sleep apnea.
The findings also revealed that sleep apnea-related factors like AHI during deep sleep, time spent breathing at less than 90 percent capacity, heart rate, sleep time and neck size affected the risk of developing diabetes.
The researchers noted that this was the largest study to date on the relationship of sleep apnea and diabetes.
"Our study, with a larger sample size and a median follow-up of 67 months was able to address some of the limitations of earlier studies on the connection between sleep apnea and diabetes," Dr. Kendzerska said in a press statement. "We found that among patients with sleep apnea, the initial severity of the disease predicted the subsequent risk for incident diabetes."
Still, the study had some limitations. The researchers did not have data on family history of diabetes, race and other potential contributing factors. Also, some of the participants may have been misclassified as having sleep apnea when they did not or as having a different severity than they actually had.
This study was published on June 5 in the American Journal of Respiratory and Critical Care Medicine.
The Institute for Clinical Evaluative Sciences provided funding.