We already know that regular naps and short sleep duration are linked with an increased risk of developing type 2 diabetes. New research now suggests that chronic insomnia may also be an important risk factor for type 2 diabetes.
Although previous research linked insomnia and type 2 diabetes, it was still unclear whether diabetes risk was influenced by intermittent insomnia, chronic insomnia, or both — or whether diabetes risk increased with insomnia duration.
This led researchers to perform a historical cohort study using data collected from Taiwan’s National Health Database between 2001 and 2010. Results were published in 2017 in the journal Diabetes/Metabolism Research and Reviews.
Investigating insomnia and diabetes risk
Researchers looked at data belonging to individuals who had been newly diagnosed with insomnia between January 2001 and December 2004 and followed this group until December 2010. Those who had been diagnosed with type 2 diabetes before they received an insomnia diagnosis were excluded, as were those who had been diagnosed with type 2 diabetes at baseline.
A total of 28,390 newly diagnosed cases of insomnia were identified. To compare diabetes risk against those without insomnia, a comparison group of 57,413 individuals without insomnia was also included in the study.
The connection between insomnia and diabetes
Researchers found the incidence rate of type 2 diabetes among those with insomnia was significantly higher than those without insomnia. The relative risk of type 2 diabetes in those with insomnia was 1.16 times greater compared to those without insomnia.
Diabetes risk was found to be significantly higher regardless of age or gender — and insomnia sufferers without comorbidities such as chronic kidney disease, chronic obstructive pulmonary disease, heart disease, high blood pressure, obesity, depression, or anxiety were also found to have a significantly higher risk of type 2 diabetes compared to those without insomnia.
How diabetes risk is influenced by insomnia duration
Diabetes risk was also found to increase in line with insomnia duration. For those who had insomnia for less than four years, diabetes risk was found to increase by 14 percent. If insomnia was present for between four and eight years, diabetes risk increased by 38 percent. When insomnia was present for more than eight years, diabetes risk increased by 51 percent.
Why does insomnia appear to increase type 2 diabetes risk?
As pointed out by the authors of this study, we still don’t know exactly why insomnia increases the risk of type 2 diabetes. With that being said, previous studies have linked sleep deprivation to an increase in hunger sensations, poor food choices, and disturbed blood sugar stability.
A 2008 study found that reduced sleep quality and low levels of slow-wave sleep reduced insulin sensitivity and glucose tolerance.
Sleep deprivation can also stimulate the body’s inflammatory response and, according to the authors of this study, this process is also associated with insulin resistance.
The findings of this study led authors to suggest that in addition to tackling established and recognized risk factors for type 2 diabetes such as obesity, diet, and exercise, we should also include treatment for sleep problems to enable more comprehensive diabetes care.