A new study has revealed increased sleep duration and chronic short sleep duration are linked to increased diabetes risk in middle-aged and older women.
Lead researcher Elizabeth Cespedes of the Harvard T.H. Chan School of Public Health stated that increasing sleep duration by 2 hours or more increased the risk of developing type 2 diabetes by 15 percent even factoring in variations in diet, physical activity, snoring, sleep apnoea, depression and body-mass index.
In the study, which included 59,031 women aged 55-83 years, change in sleep duration was recorded as the difference between self-reported 24-hour sleep duration. Diet, physical activity and covariates were updated every 2-4 years. Self-reported diabetes was confirmed via validated questionnaires.
The researchers found that chronically sleeping six hours or less per day as well as increases in sleep duration of more than two hours per day were associated with an increased risk of developing type 2 diabetes.
They also found women who increased their sleep duration were more likely to have been short sleepers to begin with, suggesting that the adverse influence of short sleep duration in mid- life may not be compensated for by later increases in sleep duration.
The authors said that chronic short sleep duration and increases in sleep duration were associated with increased risk of diabetes.
They concluded that decreases in sleep duration have modest, adverse associations with diet quality and physical activity, while increases in sleep duration have modest, adverse associations with weight gain.