Purdue researchers find connection between diabetes risk and sleep-related leg movements in interdisciplinary study

Written By: Rebecca Hoffa, rhoffa@purdue.edu

Diabetes affects approximately 38.4 million people in the United States, according to 2021 data from the Centers for Disease Control and Prevention. Researchers in Purdue University’s College of Health and Human Sciences have made a recent discovery that suggests sleep may play an important role in helping predict diabetes diagnosis.

Qinglan “Priscilla” Ding(Photo provided)

Qinglan “Priscilla” Ding, associate professor in the School of Nursing, with collaborators Laura Murray-Kolb, professor and head of the Department of Nutrition Science, and Zachary Hass, associate professor in the School of Nursing, as well as a team of clinicians are looking at the association between diabetes and sleep-related leg movements, or involuntary leg jerks that occur between five and 30 times a month.

“I think our work suggests sleep health is more than the duration you sleep or the breathing metrics,” Ding said. “Sometimes we try to associate those complications with sleep apnea, but the movement pattern of your body during your sleep may also matter for your cardiometabolic risks and deserve more attention. So, if someone noticed frequent leg jerks disrupting their sleep, it’s worth discussing with a clinician, not only because it could be a symptom related to diabetes risk but also because sleep symptoms can be part of the cardiometabolic picture and could impact our overall health.”

The study, which was funded by the National Institutes of Health, examined data from more than 9,000 adults in the U.S. using the National Health and Nutrition Examination Survey (NHANES). The researchers found a correlation between diabetes and having higher levels of sleep-related leg movements.

“We found that adults reporting frequent leg jerks actually had higher odds of having diabetes,” Ding said. “The odds are 72% higher even after adjusting for a lot of the major confounders such as obesity, hypertension and sleep apnea. We also tried to explore the mechanism that could be linking leg movements during sleep and diabetes problems. We found short sleep duration and inflammation only explained a small portion of the association. So, basically, that tells us the mechanisms between leg movement and diabetes is complex and worth studying.”

Laura Murray-Kolb(Photo provided)

Ding, who served as primary investigator on the research, became interested in this line of work after studying limb movement and diabetes risk in veterans during her doctoral work at Yale University.

“The reason why we’re studying this is because in our earlier work — we worked in a U.S. veteran cohort and with a U.S. veteran health system — we saw that a sleep phenotype that is marked by periodic limb movement in sleep was linked to later-stage diabetes risk in these veterans,” Ding said. “So, this makes us ask, does the national data show a similar signal in the general U.S. population?”

Hass, who served as a collaborator on the statistical side of the research, noted the NHANES data was instrumental in making this interdisciplinary work happen.

“The data set that was used — the NHANES data set — is a large, publicly available data set, very comprehensive,” Hass said. “Just how much value the research community gets out of that being available is hard to measure, but it is very, very valuable.”

In bringing on Murray-Kolb, who is an expert in iron and nutrient deficiencies, Ding and the team also looked at a subgroup of women who were experiencing iron deficiencies and how that impacted leg movements and diabetes risk, as iron deficiency has often been connected with restless leg syndrome and diabetes. They only found a slight association across all three factors (iron deficiency, leg movements and diabetes). Murray-Kolb noted this could be attributed to the self-reported nature of the data and could be an interesting area for future study.

Zachary Hass(Photo provided)

“It could be that some of the self-reports are not as specific as a clinical diagnosis would be, and maybe the association just isn’t as strong until it gets to that clinical diagnosis,” Murray-Kolb said. “But it is hard to know. There is a potential association with iron and diabetes, but then we see an association with diabetes and these leg movements, so there’s so much going on. Priscilla does a wonderful job of trying to control for all of these different factors, but biological systems are complicated. I think it’s one of the exciting things about these multidisciplinary types of teams because we can then think about what we might want to do next. Do we have the potential to maybe find where that missing link is?”

Ultimately, the study offers promising first steps toward future clinical assessments that could lead to earlier detection of diabetes, but additional studies are needed to further understand the correlation.

“I think that it really does add to the broader literature out there on sleep,” Murray-Kolb said. “I think we’ve known for a long time that sleep is important, but in more recent years, it’s getting more attention. We’re delving into it a little bit more and really understanding how important it is. I see Priscilla’s work as being a significant contributor to that broader literature.”