Persistently unhealthy sleep, whether it’s inadequate or excessive, is linked to a significantly higher risk of Type 2 diabetes in a varied adult population in terms of race and income, according to a team of international researchers.
Previous studies have connected suboptimal sleep durations to an increased risk of diabetes. The recent study, published in the journal Diabetologia, expanded on these findings to include a large group primarily consisting of low-income, middle-aged to older Black and white adults in the southeastern United States.
The study emphasizes the importance of maintaining regular sleep schedules over time to reduce the likelihood of developing adverse cardiometabolic conditions, stated Kelsie Full, PhD, MPH, from Vanderbilt University Medical Center.
Suboptimal sleep duration refers to sleeping less than seven hours or more than nine hours per night.
Research has shown that Black adults and individuals with lower incomes are more prone to experiencing unhealthy sleep patterns and face a higher risk of diabetes compared to their white counterparts.
The study analyzed data from approximately 36,000 adults participating in the Southern Community Cohort Study, a project monitoring the health of a diverse group across 12 southeastern states.
The study differed from previous ones by focusing on long-term sleep patterns rather than one-time measurements. It included a substantial number of Black participants with their sleep durations reported in two separate surveys conducted five years apart.
Highly variable sleep durations and extreme changes were strongly associated with diabetes risk. Such variability has been linked in other studies to poor blood glucose control, obesity, and diabetes.
The study suggests that highly variable sleep patterns in disadvantaged populations could contribute significantly to racial and socioeconomic disparities in cardiometabolic health.
While excessive sleep duration may not directly cause diabetes, it could be an indicator of other diabetes risk factors. Long sleep remains a key behavioral indicator of diabetes risk that can aid in risk assessment and disease screening.
Further research is needed to identify social and environmental factors that disrupt healthy sleep, such as living in stressful neighborhoods, and how these disruptions may affect health disparities.
The authors also recommend intervention studies to explore whether improving sleep health can help reduce health disparities in the USA.
The study received partial support from the National Institutes of Health and the NIHR Manchester Biomedical Research Centre. The Southern Community Cohort Study is backed by the National Cancer Institute of the NIH.
