Study Reveals Surprising Reason Diabetes May Be Linked to Cognitive Impairment

In previous studies, diabetes has been linked to cognitive impairment and an increased risk for dementia, but a new study sheds light on a significant factor that could be behind the link.

For the study, published in Acta Diabetologica, University of Illinois at Chicago

College of Medicine’s Sirimon Reutrakul and colleagues studied 162 patients (81with type 2 diabetes and 81 with prediabetes). The average age of the participants was 54.8 years.

Researchers obtained sleep duration and sleep efficiency information (how much time in bed was spent sleeping) using seven-day actigraphy recordings. An actigraph is a device worn on the wrist that measures motion. Researchers screened for obstructive sleep apnea using an overnight in-home monitor. They assessed cognitive function using the Montreal Cognitive Assessment (MoCA) questionnaire.

The researchers found that participants slept on average six hours per night, with an average sleep efficiency of 82.7% (meaning that 82.7% of time spent in bed was spent in sleep).

They found that the duration of sleep, as well as the severity of diagnosed obstructive sleep apnea, were not related to cognitive function as measured by MoCA. However, better sleep efficiency was associated with better cognitive function scores for participants with diabetes and prediabetes. They also found that having diabetes was associated with lower cognitive function scores, according to the study.

“The study is pertinent as it raises awareness regarding the relationship between sleep and cognition, both of which are commonly disturbed in patients with diabetes,” says Reutrakul. “Inquiring and evaluating the patients about these two factors may help discover the problems that could impact their diabetes care.” 

Sleep disturbances are more common in diabetic patients, than in patients who don’t have diabetes, according to the Joslin Diabetes Center. Having diabetes raises the risk for certain sleep problems such as sleep apnea and restless legs syndrome.