NEW YORK (Reuters Health) - Smokers may get fewer hours of sleep and have a less restful slumber than non-smokers, a new study suggests.
German researchers found that of nearly 1,100 smokers they surveyed, 17 percent got less than six hours of sleep each night and 28 percent reported "disturbed" sleep quality.
That compared with rates of seven percent and 19 percent, respectively, among more than 1,200 non-smokers.
The findings cannot prove that smoking directly impairs sleep. Smokers may have other habits that could affect their shut-eye - such as staying up late to watch TV or getting little exercise, said lead researcher Dr. Stefan Cohrs, of Charite Berlin medical school in Germany.
But there is also reason to believe smoking is to blame - namely, the stimulating effects of nicotine, Cohrs told Reuters Health in an email.
There have also been studies showing that smokers' sleep improves after they quit the habit, according to Cohrs.
"If you smoke and you do suffer from sleep problems, it is another good reason to quit smoking," Cohrs said.
Poor sleep quality may not only make your waking hours tougher: Some studies have also linked habitually poor sleep to health problems like obesity, diabetes and heart disease.
The new study, which appears in the journal Addiction Biology, included 1,071 smokers and 1,243 non-smokers who were free of mental health disorders - since those conditions may make a person both more likely to smoke and more vulnerable to sleep problems.
The researchers used a standard questionnaire that gauges sleep quality. Overall, more than one-quarter of smokers had a score that landed them in the category of "disturbed" sleep.
That means they had a "high probability" of having insomnia, according to Cohrs.
Many things can affect sleep quality. Cohrs' team was able to account for some of those factors, like age, weight and alcohol abuse. And smoking was still linked to poorer sleep quality.
It's still possible there are other things about smokers that impair their sleep. But Cohrs thinks the most likely culprit is nicotine.
Of course, there are already plenty of established reasons to kick the smoking habit. But the prospect of better sleep could offer people more motivation, Cohrs noted.
SOURCE: bit.ly/TOrYx0 Addiction Biology, online August 23, 2012.