As obesity rates climb to epidemic levels in nearly every U.S. state, one population may need to be especially weary of a serious sleep disorder linked to weight gain. People of Asian descent tend to have more severe obstructive sleep apnea (OSA) than Caucasians of similar age and BMI.

The findings are especially alarming because the Caucasians in the sample tended to be much more overweight than their Asian counterparts. Differences in facial bone structure appear to be the reason why Asians have a higher risk for OSA.

The findings were the result of a joint study between University researchers in Australia and China published in the August issue of the journal SLEEP. A sample of 74 Caucasian patients from an Australian clinic and 76 Chinese patients from a clinic in Hong Kong underwent a sleep study and a series of physical and x-ray measures.

OSA prevalence was similar for both populations, but Caucasians with OSA tended to be more overweight with a larger neck circumference. Chinese patients had smaller, more restrictive facial structures. When BMI measurements were similar the Chinese participants suffered from more frequent and severe breathing pauses during sleep.

The study may have some limitations due to the nature of the sample. The patients came from two very different environments and socioeconomic and cultural backgrounds. Researchers caution that those factors influence the health and lifestyle habits that lead to OSA.

OSA isn’t the only sleep disorder influenced by race. An abstract presented at SLEEP 2010 showed black, white, and Hispanic people all responded differently to sleep deprivation and insomnia.