WEDNESDAY, June 13 (HealthDay News) -- Race, ethnicity and country of origin appear to be factors in how much sleep Americans get each night, according to two new studies.

In one report, State University of New York researchers examined data from 400,000 participants in the U.S. National Health Interview Surveys between 2004 and 2010 and found that those born in the United States were more likely to report sleeping longer than the recommended seven to nine hours each night.

Previous research has found that adults who regularly sleep less or more than the recommended seven to nine hours may be at increased risk for health problems such as cardiovascular disease, stroke and depression.

In comparison, African-born Americans were more likely to report sleeping six hours or less per night, and Indian-born Americans were more likely to report sleeping six to eight hours a night.

However, foreign-born Americans were less likely than U.S.-born Americans to report getting too little or too much sleep after the researchers adjusted for the effects of age, sex, education, income, smoking, alcohol use, body mass index and emotional distress.

In the other study, researchers randomly selected 439 adults in Chicago and found that whites slept significantly longer than other racial/ethnic groups, blacks reported the worst sleep quality, and Asians were most likely to report daytime sleepiness.

"These racial/ethnic differences in sleep persisted even following statistical adjustment for cardiovascular disease risk factors that we already know to be associated with poor sleep, such as body mass index, high blood pressure and diabetes," study lead author Mercedes Carnethon, of Northwestern University Feinberg School of Medicine in Chicago, said in an American Academy of Sleep Medicine news release.

"And we excluded participants who had evidence of mild to moderate sleep apnea. Consequently, these differences in sleep are not attributable to underlying sleep disorders but represent the sleep experience of a 'healthy' subset of the population," she added.

The studies were to be presented Wednesday at the annual meeting of the Associated Professional Sleep Societies in Boston. Because this study was presented at a medical meeting, the data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.

More information

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