Snoring, apnea linked to diabetes risk in older adults

By Madeline Kennedy

Sleep-disordered breathing may nearly double the risk of type 2 diabetes for older patients, researchers say.

"Recent evidence suggests that diabetes patients have a higher prevalence of sleep disturbances than the general population," lead author Dr. Linn Beate Strand told Reuters Health by email. "However, less is known about whether symptoms of sleep-disordered breathing increase the risk of developing type 2 diabetes later, especially in older adults."

Most previous studies on sleep disorders and diabetes have focused on young or middle-aged adults, the researchers pointed out online September 17 in Diabetes Care.

Dr. Strand, of the Beth Israel Deaconess Medical Center in Boston, and colleagues analyzed data from 5,888 U.S. adults recruited between 1989 and 1993 at age 65 or older. None had type 2 diabetes at baseline.

Every six months through 1999, the researchers surveyed participants to ask whether anyone had observed them having episodes of sleep apnea, whether a spouse or roommate had complained about their loud snoring and whether they were usually sleepy during the day.

The researchers also asked about insomnia symptoms such as difficulty falling asleep, frequent awakening at night, or waking up too early and being unable to go back to sleep.

Early in the study, participants underwent oral glucose tolerance testing, from which insulin secretion and insulin sensitivity were estimated. Fasting blood sugar levels were measured multiple times over the years.

"None of the individual sleep-disordered breathing symptoms were associated with fasting glucose in the cross-sectional analyses," the authors reported. "There was, however, a graded trend toward increased fasting glucose levels with an increasing number of sleep-disordered breathing symptoms."

Also, they found, patients with daytime sleepiness had higher 2-hour glucose levels, which were "much higher" with an increasing number of symptoms.

The risk of diabetes was increased with sleep apnea (hazard ratio 1.84), snoring (HR 1.27), and daytime sleepiness (HR 1.54).

Insomnia symptoms, however, were not consistently linked to the risk of diabetes.

"The findings suggest that improving sleep quality in older adults may reduce their risk of developing diabetes or may reduce the severity of diabetes in those who are already affected," Dr. Eve Van Cauter, who was not involved in the study, told Reuters Health by email.

Dr. Van Cauter, a sleep and metabolism researcher at the University of Chicago, noted that although sleep disturbances can cause problems for nearly all aspects of health, they're often ignored when treating diabetes.

"Monitoring blood sugar levels in older adults with sleep disturbances may help identify individuals potentially at risk to allow earlier interventions," Dr. Strand said.

The National Institutes of Health supported this research.

SOURCE: bit.ly/1VcPG1o

Diabetes Care 2015.

(c) Copyright Thomson Reuters 2015. Click For Restrictions - http://about.reuters.com/fulllegal.asp