MONDAY, June 27 (HealthDay News) -- Women who often work at
night may face higher odds of developing type 2 diabetes, a new
study suggests.
The study, which focused only on women, found that the effect
got stronger as the number of years spent in shift work rose, and
remained even after researchers accounted for obesity.
"Our results suggest that women have a modestly increased risk of type 2 diabetes mellitus after extended period of shift work, and this association appears to be largely mediated through BMI [weight]," concluded a team led by An Pan, a researcher in nutrition at the Harvard School of Public Health in Boston.
His team was slated to present its findings Sunday in San Diego
at the annual meeting of the American Diabetes Association.
Prior studies have suggested that working nights disrupts
circadian (day/night) rhythms, and such work has long been
associated with obesity, the cluster of cardiovascular risk factors
known as the "metabolic syndrome," and dysregulation of blood
sugar.
In the new study, researchers looked at data on more than 69,000
U.S. women tracked from 1988 to 2008 as part of the Nurses Health
Study. Almost 6,200 women developed type 2 diabetes over the course
of the study.
Beginning at their entry into the study, women were asked how
long they had worked rotating night shifts (including at least
three nights of work per month).
The researchers found that the risk of developing type 2
diabetes rose with increasing duration of shift work. After
adjusting for obesity, women who'd worked night shifts regularly
for three to nine years faced a 6 percent rise in risk, while women
who had done so for 10 to 19 years saw their risk rise by 9
percent, and those who had worked such shifts for 20 years or more
faced a 20 percent increase in risk.
Weight gain accounted for some, but not all, of the night
shift-linked rise in diabetes risk, the team noted.
Experts note that research presented at meetings is typically
considered preliminary until published in a peer-reviewed
journal.
More information
Find out more on reducing your risk for type 2 diabetes at the
U.S. National Institute of Diabetes and Digestive ...
Kidney Diseases.