A new study from the National Institutes of Health has established a strong link between sleep quality and diabetes risk. The researchers found that African Americans with sleep apnea and other sleep-related issues are more likely to have high blood glucose levels.
The research suggests that maintaining good sleep habits helps to protect against type 2 diabetes by controlling blood sugar.
The research team emphasized that screening for sleep apnea is important to prevent uncontrolled blood glucose levels among high-risk groups, including African-Americans.
Previous studies have linked poor sleep patterns, particularly those associated with sleep apnea, to elevated blood sugar levels in white and Asian populations.
The researchers said the study is one of the first to use objective measurements to link poor sleep quality to increased blood glucose levels in black men and women.
Study lead author Dr. Yuichiro Yano is a researcher in the Department of Family Medicine and Community Health at Duke University.
“The study underscores the importance of developing interventions to promote regular sleep schedules, particularly in those with diabetes,” said Dr. Yano. “It also reaffirms the need to improve the screening and diagnosis of sleep apnea, both in African Americans and other groups.”
The researchers analyzed the sleep patterns and correlating blood sugar levels of nearly 800 African-American men and women. The study was focused on data from the Jackson Heart Study, the largest study of cardiovascular disease in African-Americans.
The majority of the participants were women with an average age of 63. Around 57 percent of the individuals had been diagnosed with obstructive sleep apnea but were not receiving treatment, and 25 percent had type 2 diabetes.
The individuals conducted sleep tests at home with a tracking device that measured sleep activity for seven days. The tests calculated sleep duration, sleep quality, variability in sleep duration, and sleep fragmentation.
The researchers obtained several measures of glucose metabolism, including fasting blood glucose concentration, HbA1c levels, and insulin resistance.
The participants were divided into four groups: no sleep apnea, mild sleep apnea, moderate sleep apnea, and severe sleep apnea.
The study revealed that individuals with severe sleep apnea had higher fasting blood glucose levels by 14 percent compared to those without sleep apnea. Dr. Yano explained that severe sleep apnea was also associated with higher HbA1c levels.
Participants who experienced poor sleep patterns like sleep fragmentation and sleep duration variability were also more likely to have increased measures of blood glucose.
The researchers noted that associations between poor sleep quality and high blood glucose levels were stronger in participants with diabetes. Among individuals without diabetes, disturbed sleep was still tied to increased insulin resistance, which is a precursor of diabetes.
Dr. Yano and his team determined that the link between sleep apnea and high blood glucose levels was stronger among black men than black women.
Dr. Michael Twery, director of the NHLBI’s National Center on Sleep Disorders Research, said the study highlights important associations between untreated sleep apnea and poorly-regulated blood sugar. “It also adds to growing evidence that protecting our sleep, like diet and exercise, may help reduce the risk of diabetes and the related risk of cardiovascular disease.”
The researchers concluded that interventions to treat sleep apnea, including the use of continuous positive air pressure (CPAP) machines, may help improve blood glucose management – particularly in those with diabetes.
The study is published in the Journal of the American Heart Association.