A single, simple question about sleep habits asked to people with diabetes in the UK Biobank database identified a subgroup with a nearly doubled mortality rate during almost 9 years of follow-up: those who said they usually had sleep disturbances.
Dr. Kristen L. Knutson
The question was: Do you never, rarely, sometimes, or usually have trouble falling asleep, or waking in the middle of the night?
Adults in the UK Biobank with any form of self-reported diabetes or insulin use who answered that they usually have sleep disturbances had a significant 87% higher mortality rate than did those without diabetes who said they never or rarely had sleep disturbances, in a fully adjusted model with an average follow-up of 8.9 years, Kristen L. Knutson, PhD, and coauthors reported in the Journal of Sleep Research.
Mortality was 11% higher in respondents who reported frequent sleep disturbances but had no diabetes than in those without frequent sleep disturbances. Furthermore, those with diabetes but without frequent sleep disturbances had a 67% higher mortality rate, compared with those without diabetes. Both differences were statistically significant in a model that adjusted for age, sex, ethnicity, smoking, sleep duration, body mass index, and other covariates.
The findings suggest that diabetes and frequent sleep disturbances act in a roughly additive way to raise mortality risk, said Dr. Knutson, an epidemiologist and neurologist who specializes in sleep medicine at Northwestern University, Chicago.
She suggested that, based on these findings, clinicians should consider annually asking patients with diabetes this key question about the frequency of their sleep disturbances. They should then follow up with patients who report usual disturbances by referring them to a sleep clinic to test for a sleep disorders such as insomnia or sleep apnea. Sleep apnea especially is “particularly common in patients with type 2 diabetes,” Dr. Knutson noted in an interview.
A need to ‘spread awareness’ about diabetes and disturbed sleep.
The study run by Dr. Knutson and associates “is one of the largest population-based studies” to examine the relationship between sleep disturbances, diabetes, and mortality, commented Sirimon Reutrakul, MD, an endocrinologist and diabetes specialist at the University of Illinois Hospital in Chicago.
“This study highlights the detrimental effects of sleep disturbances in people with or without diabetes, and adds to the effects of sleep disturbances such as insomnia symptoms. People with diabetes often have sleep disturbances. Obstructive sleep apnea is very common in people with diabetes, and insomnia symptoms could be present in people with obstructive sleep apnea or it could be a separate problem,” Dr. Reutrakul said in an interview. Sleep disturbances can arise from direct effects of diabetes, such as nocturia, worry about glucose levels, pain, depressive symptoms, and anxiety, or can result from comorbidities that interfere with sleep.
“It is prudent to ask patients with diabetes about sleep patterns,” said Dr. Reutrakul, and she endorsed the specific question that Dr. Knutson recommended asking patients. Other aspects of sleep quality that could be helpful for a diagnosis include sleep duration, sleep timing, and snoring. “Some physicians ask these questions, but we need to spread awareness,” she added.
Prior to referring patients to a sleep clinic, Dr. Reutrakul suggested that clinicians could also assess possible triggers such as inadequate glucose control, pain, and anxiety, and they could also recommend good sleep hygiene strategies such as what’s recommended by the Sleep Foundation.