Smokers may have more trouble sleeping than non-smokers, according to a new study from German researchers.
The findings, published in the journal Addiction Biology, suggest that smokers are more likely to not get enough sleep each night and have disturbed sleep than people who don't smoke cigarettes, Reuters first reported.
The study is based on the sleep habits of 1,071 people who smoke and 1,243 people who don't smoke. The researchers found that 28.1 percent of the smokers had disturbed sleep quality, compared with 19.1 percent of nonsmokers. And 17 percent of smokers also reported getting six or fewer hours of sleep a night, compared with 7 percent of nonsmokers, Reuters reported.
"It appears likely that smoking is a behaviourally modifiable risk factor for the occurrence of impaired SQ [sleep quality] and short sleep duration," the researchers wrote in the study.
In 2008, scientists from the Centers for Disease Control and Prevention also found that people who get fewer than six hours of sleep every night had higher rates of smoking, as well as obesity, alcohol use and physical inactivity, PsychCentral reported.
And in another study in the journal CHEST, researchers from the Johns Hopkins University School of Medicine found that smokers have a four-times higher risk of unrestful sleep than people who don't smoke. They are also more likely to experience light -- rather than deep -- sleep.
"It is possible that smoking has time-dependent effects across the sleep period," study researcher Dr. Naresh M. Punjabi, M.D., Ph.D., FCCP, said in a statement. "Smokers commonly experience difficulty falling asleep due to the stimulating effects of nicotine. As night evolves, withdrawal from nicotine may further contribute to sleep disturbance."