WEDNESDAY, June 11 (HealthDay News) -- Children with bigger necks are more likely to develop a sleep-related breathing disorder, says a University of Virginia study.

Researchers looked at 215 children, aged 18 months to 18 years, who were referred to a pediatric sleep center. Of these children, 37.3 percent were obese and had an increased frequency of snoring.

The children's neck size, in the sitting and neutral head position, was measured and apena-hypopnea index (AHI) and mean oxygen saturation values were used as indicators of the severity of the sleep-related breathing disorder.

Age-adjusted neck size correlated with body-mass index (BMI) and weight and showed a higher correlation with AHI than did BMI, weight or tonsil size. Neck size also showed a strong inverse correlation with mean oxygen saturation and was a better predictor of mean oxygen saturation than BMI, weight or tonsil size, the study found.

"Children with bigger neck sizes for age should be queried about snoring, apnea, excessive sleepiness, and hyperactivity. Neck size should be considered in the clinical evaluation of children with a history of snoring and apnea," study author Dr. Pearl L. Yu said in a prepared statement.

The findings were expected to be presented at the annual meeting of the Associated Professional Sleep Societies, in Baltimore.

Sleep-related breathing disorders affect breathing during sleep. The most common type is obstructive sleep apnea (OSA), which occurs when the tissue in the back of the throat collapses and blocks the airway.

OSA occurs in about 2 percent of young children, according to background information in a news release about the study. OSA can develop in children at any age but is most common in preschoolers, when the tonsils and adenoids are large compared to the throat. OSA is also common obese children.

In early childhood, OSA can slow a child's growth rate. Untreated OSA can also lead to high blood pressure.

More information

The Nemours Foundation has more about children and sleep apnea.