(HealthDay News) — Increased sleep duration is associated with increased risk for incident type 2 diabetes, according to a study published in Diabetes Care.
Jane E. Ferrie, PhD, from the University of Bristol in the United Kingdom, and colleagues examined whether a change in sleep duration is associated with incident diabetes using data waves spanning more than 20 years. Sleep duration was reported at the beginning and end of four 5-year cycles from 1985-1988 to 2007-2009.
The researchers found that after adjustment for age, sex, employment grade and ethnic group, an increase of at least 2 hours of sleep per night correlated with an increased risk for incident diabetes compared with a reference group of persistent 7-hour sleepers (OR=1.65; 95% CI, 1.15-2.37).
After adjustment for BMI and change in weight, the correlation was partially attenuated (OR=1.50; 95% CI, 1.04-2.16). Persistent short sleepers (average of 5.5 hours or less per night) had an increased risk for incident diabetes (OR=1.35; 95% CI, 1.04-1.76), but the correlation was no longer significant after adjustment for BMI and change in weight (OR=1.25; 95% CI, 0.96-1.63).
“This study suggests that individuals whose sleep duration increases are at an increased risk of type 2 diabetes,” the researchers wrote. “Greater weight and weight gain in this group partly explain the association.”