Good night's sleep is no slumber party for smokers

WASHINGTON (Reuters) - For smokers, getting a good night's sleep is no slumber party, scientists said on Monday.

Researchers who tracked the brain activity of smokers while they slept found that they spent less time in deep sleep than nonsmokers. Smokers were also about four times as likely to complain that their sleep did not leave them well rested.

The nicotine from cigarettes seems to be a nightmare for sleeping smokers. Because it can act as a stimulant, nicotine makes it harder to fall asleep, the researchers said. And minor withdrawal symptoms that occur as the night drags on can further disturb a smoker's sleep, they added.

Researchers led by Dr. Naresh Punjabi of Johns Hopkins University School of Medicine in Baltimore set out to learn more about the sleep problems that bedevil many smokers.

"Smokers undoubtedly, when you look at the (medical) literature, have sleep-related difficulties. They have difficulty falling asleep and difficulty maintaining sleep," Punjabi said. "The question is why do they have this."

A key issue was whether sleep problems could be blamed on the many medical complications brought on by smoking -- symptoms of lung or heart disease, for instance -- or whether smoking itself was the culprit, Punjabi said.

The researchers identified a group of 40 middle-aged smokers who had none of the many medical conditions associated with smoking, and compared their sleep patterns to those of an equal number of nonsmokers of the same age and physical type.

While sleeping at their homes, they were hooked up to electroencephalogram or EEG machines, which record the brain's electrical activity. Compared to nonsmokers, smokers spent less time in deep sleep and more time in light sleep, the researchers found.

The biggest differences took place in the period just after falling asleep, supporting the idea that nicotine's effects are most acute in early stages of sleep, according to the study.

In addition, about 23 percent of smokers reported they had not had restful sleep, compared to 5 percent of nonsmokers.

The findings were published in the journal Chest, published by the American College of Chest Physicians.

"This study provides yet one more reason to stop smoking or to never start," Dr. Alvin Thomas, president of the American College of Chest Physicians, said in a statement.

Punjabi said the findings could be important in coming up with better ways to help smokers quit, for instance by tailoring nicotine replacement therapy to minimize withdrawal effects that smokers may experience during sleep."

"This is very critical for smoking cessation because one of the major complaints that smokers tend to have when they start quitting is sleep dysfunction," Punjabi said.

(Editing by Maggie Fox and Todd Eastham)