Less sleep for kids may mean higher blood sugar

Children sleep inside an evacuation center for victims hit by floods caused by Typhoon Ketsana, locally known as Ondoy, in the town of Taytay, Rizal east of Metro Manila, October 13, 2009.

NEW YORK (Reuters Health) - Young children may be more apt to have high blood sugar, a precursor to diabetes, if they average 8 hours or less of sleep a night, report Chinese and American researchers.

This risk may be even greater among obese youngsters, Dr. Zhijie Yu, at the Chinese Academy of Sciences in Shanghai and colleagues note in Archives of Pediatric and Adolescent Medicine.

Moreover, Yu said in an email to Reuters Health, shorter sleep seemed to influence blood sugar "independently of a large variety of risk factors," such as age, gender, birth-related influences, early life feeding or later diet, recent illness, physical activity, body mass, and waist girth.

Yu's team investigated sleep duration and blood sugar levels in 619 obese and 617 non-obese children who were 3 to 6 years old and free of diabetes or blood sugar problems.

Parental reports showed a greater percentage of the obese (47 percent) than the non-obese (37 percent) kids averaged 8 or fewer hours of sleep nightly. These reports also showed nightly averages of 9 or 10, or 11-plus, hours of sleep less common in obese (37 and 16 percent) versus non-obese (43 and 20 percent) kids, respectively.

High blood sugar levels, defined as 100 milligrams of glucose per deciliter of blood after not eating for 8 hours, appeared about 1.35-fold and 2.15-fold more likely in the shorter-sleeping non-obese and obese kids, respectively. (For comparison, 110 milligrams per deciliter is considered "pre-diabetes," while diabetes is diagnosed at 126 milligrams.)

High blood sugar levels were evident in 23 of the 217 non-obese and in 49 of the 291 obese kids sleeping less than 8 hours. By contrast, 21 each of the 175 non-obese and 229 obese kids getting 9 or 10 hours of sleep nightly had high blood sugar.

Overall, 11 of the children had levels above 126 milligrams per deciliter, the level at which diabetes is diagnosed.

These findings hint that, similar to adults, adequate sleep may help kids, "maintain a healthy body weight and an optimal (blood sugar) level," Yu said.

However, Yu's team highlights the need for further studies to confirm these findings in both Chinese and other populations of youngsters.

SOURCE: Archives of Pediatric and Adolescent Medicine, January 2010