According to a recent cohort study, publish in ADA Diabetes Care, self-reported short and long sleep times were associated with glycemic values out of normal range in patients with prediabetes and recently diagnosed, untreated patients with diabetes. Also, short sleep times and shift work patterns; found to be associated with higher BMI values within the same population.

It is important to interview patients regarding their sleep time; and sleep quality as a part of examining the patient as a whole, especially upon observing signs of potential prediabetes or diabetes. Sleep, among many other lifestyle factors; may impact the progression of diabetes including the efficacy of treatment.

But over the last decade, prospective epidemiologic studies have found an association with sleep disturbances; such as short and long sleep duration, poor sleep quality, obstructive sleep apnea, and circadian misalignment; and type 2 diabetes. But few studies have examined whether sleep quality; or circadian misalignment are associated with uncontrol glycemic values, independent of BMI and physical activity.

Prediabetes not explored

However, the association of sleep disturbances and glycemic control in patients; with prediabetes has not explored. The objective of this cohort study was to examine the relationship between self-reported sleep times; sleep quality, and circadian misalignment (social jet lag, late chronotype, or shift-work) with glycemic control; BMI, and blood pressure in adults with type 2 diabetes, or prediabetes.

A cross-sectional analysis of data from the screening phase; of the Restoring Insulin Secretion (RISE) consortium of randomized controlled trials performed. Men (55%) and women (45%), aged 20-65 years old; with obesity or overweight  recruited from four adult health centers across the United States. All patients underwent a fasting plasma glucose measurement, HbA1c measurement; and 75-g oral glucose tolerance test (OGTT) including a plasma glucose measurement at 2 hours.

Patients must have met the American Diabetes Association definition of prediabetes (fasting plasma glucose 100-125 mg/dL, 2-h plasma glucose 140-199 md/dL, or HbA1c 5.7-6.4%) as well as have been recently diagnosed within one year. Untreated participants with existing type 2 diabetes; defined by the American Diabetes Association, (fasting plasma glucose 126 mg/dL, 2-h plasma glucose  200 mg/dL, or HbA1c  6.5%) also included. Weight and blood pressure measurements taken.

Sleep duration and sleep quality

But to assess sleep, The Pittsburgh Sleep Quality Index (PSQI) questionnaire, The Berlin Questionnaire, and the Epsworth Sleepiness Scale (ESS) use. Of the 962 participants, 704 had prediabetes and 258 had diabetes.  After adjustment for age, sex, race/ethnicity, and BMI, those reporting an average of <5 hours and >8 hours of sleep daily had significantly higher HbA1c values compared to those with 7-8 hours of sleep. Fasting glucose directly associate with sleep duration.

BMI inversely associated with sleep duration and sleep quality, and directly associate with excessive daytime sleepiness. This study serves as a good background for understanding the relationship sleep has with control of diabetes and other important metabolic values.

The cohort had a significant amount of ethnically diverse participants, with a near even divide between men and women, supporting its generalizability. Important factors that may impact participants’ BMI and glycemic control such as diet, meal timing and physical activity not accounted for in this study. However, further studies should conducted to make stronger conclusions regarding the impact of sleep on glycemic control.