Smoking interferes with thinking and memory in recovering alcoholics

Non-smoking recovering alcoholics outperform smoking recovering alcoholics on tests of memory, cognition, visual and auditory learning, and memory

After six to nine months of abstinence from alcohol, recovering alcoholics who were also chronic smokers showed a significantly lower rate of improvement in tests of memory, reasoning, judgment, and visual/spatial coordination than non-smoking recovering alcoholics in a study conducted by researchers at the San Francisco VA Medical Center (SFVAMC).

Not only did the smokers improve less, but their overall scores were lower than the non-smokers on most neurocognitive measures tested by the researchers.

“This suggests that continued smoking during abstinence from alcohol may adversely affect recovery,” says Timothy Durazzo, PhD, the study’s lead author and a research scientist in radiology at SFVAMC.

The study appears in the July, 2007 issue of Alcoholism: Clinical & Experimental Research.

Durazzo, who is also an assistant adjunct professor of radiology at the University of California, San Francisco (UCSF), says the study is significant in light of previous research indicating that 60 to 80 percent of people who seek treatment for alcoholism are chronic smokers.

“It’s well-established that chronic alcohol abuse leads to abnormalities in brain neurobiology and neurocognitive function, and it’s also been shown that smoking itself leads to neurobiological and neurocognitive dysfunction,” he says. “We wanted to learn what effect continued chronic smoking might have on changes in neurocognitive function during abstinence from alcohol. This issue had not been investigated before.”

The researchers compared neurocognitive function among 13 non-smoking recovering alcoholics and 12 actively smoking recovering alcoholics recruited from two substance abuse recovery programs in San Francisco. After approximately one month of self-reported abstinence from alcohol, the subjects were tested on an array of neurocognitive abilities known to be affected by chronic alcohol abuse: auditory/verbal learning and memory; visual/spatial learning and memory; cognitive efficiency (speed and accuracy of intellectual task performance); executive skills (higher order thinking, reasoning, judgment, and planning); processing speed; working memory (short-term memory); motor functioning; and postural stability. The results were compared with those of 22 non-smoking, light drinking controls.

After six to nine months of alcohol abstinence, the subjects and controls were re-tested. The smokers showed significantly less improvement than the non-smokers in cognitive efficiency, executive skills, working memory, and visual/spatial learning and memory. Overall, their performance in tests of auditory/verbal learning and memory, cognitive efficiency, executive skills, processing speed, and working memory was inferior to that of the non-smokers.