Differences in sleep duration linked to type 2 diabetes, study reports

People who have increased sleep duration face a heightened risk of developing type 2 diabetes, according to a University of Bristol study.
Researchers examined data waves across more than 20 years, with sleep duration reported at the beginning and end of four cycles – each of which was five years long. The study took place between 1985 and 2009.
Changes in sleep duration were calculated for participants without diabetes, with fasting glucose, HbA1c and an oral glucose tolerance test administered at the end of each five-year period.
Compared to a control group who sleep for seven hours a night, people who slept for two additional hours per night were found to have a higher risk of incident type 2 diabetes. This was still the case when age, ethnic group, sex and employment grade were accounted for.
An increased risk was also observed in persistent short sleepers who slept for an average of less than 5.5 hours per night.
However, the significance of these findings was reduced, the researchers reported, when adjustments for BMI and changes in weight during the study were considered.
While the findings suggest that sleep duration affects one’s risk of incident type 2 diabetes, “greater weight and weight gain in this group partly explain the associatio,” according to the researchers.
Further studies on this topic is required, therefore, to investigate this link further and assess if sleep duration can impact the development of type 2 diabetes without weight being a factor.
The findings of this study were published in the online journal Diabetes Care.