Sarah S. Jaser
Adolescents with type 1 diabetes who displayed a greater variability in sleep duration between weekdays and weekends were more likely to monitor blood glucose less frequently, have a higher HbA1c and spend less time in the target blood glucose range vs. children who maintain a regular bedtime, according to findings published in Pediatric Diabetes.
“Sleep is a potential risk or protective factor for diabetes-related outcomes in adolescents with type 1 diabetes,” Sarah S. Jaser, PhD, associate professor of pediatrics at Vanderbilt University Medical Center in Nashville, Tennessee, told Endocrine Today. “In particular, we found that greater variability in sleep duration, or differences between school night and weekend night sleep duration, was related to poorer glycemic control and self-care behavior. Furthermore, most of the adolescents in our sample were not meeting recommendations for sleep duration (average sleep time was 6 hours, 54 minutes).”
Jaser and colleagues analyzed data from 65 adolescents with type 1 diabetes and their caregivers, recruited during scheduled clinic appointments (80% white; mean diabetes duration, 6 years; 59% on pump therapy). Adolescents and caregivers received training on using an actigraph watch (Phillips Actiwatch Spectrum Plus), with adolescents instructed to wear the watch continuously for 7 days, pressing an event marker at “lights out” and “lights on” to determine time in bed. Adolescents also completed a daily sleep diary for the corresponding 7 days, recording daytime sleep-related behaviors (caffeine use, daily activity level, electronics in the room) and nocturnal sleep characteristics, as well as diabetes-specific factors that may influence sleep (blood glucose monitoring at bedtime, overnight and in the morning). Adolescents and their caregivers completed the Self-Care Inventory, which measures adherence to diabetes treatment, and the Pittsburgh Sleep Quality Index, a validated self-report measure. Researchers also assessed HbA1c levels collected as part of regular diabetes clinic visits and obtained average daily blood glucose monitoring by downloading adolescents’ glucometer readings to measure adherence.
Researchers used bivariate analyses to determine associations between variability in sleep duration, total sleep time and self-reported sleep quality with diabetes-related outcomes and linear regression analyses to determine whether total sleep time or variability in sleep duration were predictors of glycemic control and diabetes management.
In the 30 days before sleep data collection, mean blood glucose level for the cohort was 221.03 mg/dL, with about 24% of blood glucose levels in the target range. Across 7 nights, mean total sleep tome was 6 hours, 54 minutes per actigraphy data; mean onset latency was 17.8 minutes and mean sleep efficiency was 84.6%. Based on sleep diary data, adolescents reported a mean sleep duration of 8 hours, 18 minutes. Mean and median bedtime across 7 nights was 11:15 p.m. and 11 p.m., respectively, and reported mean and median wake-up times of 7:34 a.m. and 7 a.m., respectively. Sleep variability ranged from 21.2 minutes to 164.8 minutes, with a mean of 73 minutes.
Researchers did not observe an association between total sleep time and sleep quality and any diabetes-related outcomes, nor did they observe an association between sleep variability and parent- or self-reported outcomes. However, researchers identified an association between greater variability in sleep duration and less frequent blood glucose monitoring (P < .05) and between sleep variability and HbA1c (P < .01). Researchers also noted a relationship between sleep variability and blood glucose levels (P < .05) and percentage of glucose levels within target range (P < .05).
“Sleep is not often addressed in diabetes clinic visits, and our findings support that providers should be asking about sleep duration and timing and making basic recommendations for achieving sufficient and consistent sleep,” Jaser said. “For example, providers can encourage earlier weekend bedtimes and a more consistent sleep schedule as a way to improve diabetes management.”
Jaser added that the associations between sleep and glycemic control are likely bidirectional, with poor glycemic control increasing the likelihood of nocturnal hypoglycemia and hyperglycemia, which can disrupt sleep.
“Our research team is currently conducting a pilot study of a sleep-promoting intervention in teens with type 1 diabetes to determine if we can improve sleep habits and glycemic control,” Jaser said. – by Regina Schaffer
For more information:
Sarah S. Jaser, PhD, can be reached at Vanderbilt University Medical Center, 2525 West End Ave., Suite 1200, Nashville, TN 37203; email: email@example.com.
Disclosures: The National Institute of Diabetes and Digestive and Kidney Diseases supported this study. The authors report no relevant financial disclosures.