Long-term alcoholism can have detrimental effects on a person's sleep despite long periods of abstinence, according to a study.
And the above pattern is similar in both men and women.
Results indicate that in long-term alcoholics who had not had a drink for up to 719 days, the percentage of slow wave sleep was significantly lower (6.6 percent in men, 11.1 percent in women) than in controls (12.0 percent in men, 12.1 percent in women).
Alcoholics also had significantly more stage 1 non-rapid eye movement (NREM) sleep (8.5 percent in men, 6.3 percent in women) than controls (6.2 percent in men, 5.6 percent in women).
The researchers say that having less deep, slow wave sleep and more light, stage 1 sleep reflects poorer sleep quality, which could act as an exacerbating factor in alcoholics' cognitive decline.
Although women had better sleep efficiency and fewer wake periods than men, the researchers found no significant interactions between sex and alcoholism diagnosis.
Thus, they concluded that women show the same general pattern of alcoholism-related sleep changes as men.
Principal investigator Dr. Ian Colrain at the University of Melbourne in Australia, also was surprised to find that a significant increase in the percentage of REM sleep persisted in alcoholics who had abstained from drinking for an extended period.
"Previously the REM changes in the acute detox period were assumed to be related to a rebound of the REM suppression effects of alcohol. The persistence indicates that there is some possibly permanent structural/functional change in REM regulation mechanisms produced by long-term alcohol abuse," said Colrain.
The study has been published in the journal Sleep.