Frequent napping is associated with increased risk of type 2 diabetes in older adults, a new study claims.
The study published in March 1 issue of the journal Sleep showed that the prevalence of type 2 diabetes was 36 percent higher in participants who reported napping four to six times a week and 28 percent higher in those who napped daily.
Similar associations were found between napping and impaired fasting glucose. The observed associations were unaltered in statistical analyses that removed participants with potential ill health and daytime sleepiness, suggesting it is less likely that diabetes leads to daytime sleepiness and raising the possibility that napping may increase the risk of diabetes.
Lead author Neil Thomas, PhD, reader in epidemiology at the University of Birmingham, U.K., said that additional research is needed to determine if napping itself plays a causative role in the development of type 2 diabetes, or if other factors are involved.
"In many non-Mediterranean, Western countries a large proportion of those that nap are generally older or have other conditions that cause tiredness and create an urge to nap," said Thomas. "The napping can therefore be a marker of disease."
The cross-sectional study analyzed baseline data from the Guangzhou Biobank Cohort Study, a collaboration between the Guangzhou Number 12 People's Hospital and the Universities of Birmingham and Hong Kong. The community-based study took place in Guangzhou, China, where 19,567 participants between the ages of 50 and 93 years were recruited from 2003 to 2004 and 2005 to 2006. The sample comprised 13,972 women with a mean age of 61.4 years and 5,595 men with an average age of 64.2 years.