Experiencing frequent sleep disturbances significantly increases the chances of dying of any cause. Everyone is affected, but people with diabetes seem to experience a larger effect.
An international study, led by Dr Kristen Knutson, from Northwestern University Feinberg School of Medicine, in the United States, assessed how insomnia and diabetes (mostly Type 2 diabetes) were correlated with mortality risk. The study is the first in the world to examine how the combination of insomnia and diabetes affects the risk of all-cause mortality (death from any cause).
After analysing lifestyle and morbidity data from nearly half a million men and women from the UK, who were 37-73 years old, Dr Knutson found significant associations between sleep patterns and all-cause mortality.
People with diabetes, who experienced frequent sleep disorders, seem to experience the highest risk of death: they had an 87% higher chance of dying from any cause, compared to people without diabetes or with better sleeping habits.
About the findings
The collect data about sleeping patterns, researchers sent out a single question to more than 500,000 participants of the UK Biobank study: “Do you have trouble falling asleep at night or do you wake up in the middle of the night? Three possible responses were available: “never/rarely”, “sometimes” or “usually”.
About 99.9% of participants responded this question and based on their responses, researchers found that more than 75% of respondents experienced sleep disturbances, either sometimes or usually. The study also identified the most common characteristics of people experiencing sleep disturbances.
“On average, those who reported frequent sleep disturbances were older, had a higher BMI, slept less, and were more likely to be female, white, current smokers, and have depression and diabetes,” the authors reported.
The authors then evaluated if having sleep disturbances was associated with all-cause mortality and with mortality due to cardiovascular disease. Their analyses showed that people with diabetes and frequent sleep disturbances were 87% more likely to die of any cause during the 8.9-year follow-up period of the study, compared to people without diabetes or without sleep disturbances. Having diabetes alone, and no sleep disturbances was also associated with an increased risk of all-cause death, of about 12%.
“Although we already knew that there is a strong link between poor sleep and poor health, this illustrates the problem starkly,” said first study author Malcolm von Schantz, professor of chronobiology from the University of Surrey, in a press release.
“The question asked when the participants enrolled does not necessarily distinguish between insomnia and other sleep disorders, such as sleep apnea. Still, from a practical point of view it doesn’t matter. Doctors should take sleep problems as seriously as other risk factors and work with their patients on reducing and mitigating their overall risk,” he added.
Advice for patients and GPs
The key take-home message from this study is that sleep quality is a very important factor influencing our health. Even without diabetes, chronic poor sleep can bring significant health problems.
“If you don’t have diabetes, your sleep disturbances are still associated with an increased risk of dying, but it’s higher for those with diabetes,” Dr Knutson said in a press release.
“But by answering one simple question (’Do you have trouble falling asleep at night or do you wake up in the middle of the night?’) people can begin to address sleep disturbances earlier in life and hopefully mitigate this increased risk of death,” she added.
According to Dr Knutson this is a simple question that anyone, patients and clinicians, should ask.
“But it’s a very broad question and there are a lot of reasons you might not be sleeping well. So it’s important to bring it up with your doctor so they can dive deeper. Is it just noise or light or something bigger, like insomnia or sleep apnea? Those are the more vulnerable patients in need of support, therapy and investigation into their disease,” Dr Knutson said.