Smoking Ups Neuropsychological Toll in Drinkers

Article excerpt

SANTA BARBARA, CALIF. -- Smoking appears to heighten neuropsychological deficits found in heavy social drinkers, researchers reported at the annual meeting of the Research Society on Alcoholism.

Specifically, deficits in executive functioning and balance seen in people who both smoked and drank heavily were significantly worse than those seen in heavy-drinking nonsmokers, said Timothy C. Durazzo, Ph.D., a neuropsychologist and neuroscience researcher at the San Francisco Veterans Administration Medical Center.

"We believe smoking may compound alcohol-induced neurobiologic and neurocognitive dysfunction among individuals with alcohol use disorders," said Dr. Durazzo following the meeting.

The neuropsychological results build on Dr. Durazzo's earlier identification--by MRI and magnetic resonance spectroscopy--of specific brain metabolite deficits in the frontal lobes and subcortical structures of smokers who had recently undergone alcohol detoxification (Alcohol. Clin. Exp. Res. 2004;28:1849-60).

The study concluded that smoking exacerbates alcohol-related frontal lobe neuronal injury and cell membrane damage, but also has an independent adverse effect on subcortical structures.

In the current study, Dr. Durazzo and associates administered neuropsychological tests to 33 socially functioning heavy drinkers, 13 of whom were also daily smokers, and 22 nonsmoking light drinkers.

Heavy drinking was defined as consuming more than 80 drinks per month, but study subjects actually consumed considerably more. Nonsmoking heavy drinkers averaged 141 lifetime drinks per month, while heavy drinkers who smoked drank an estimated 227 drinks per month.

Subjects were mostly in their early 40s with a relatively high level of education (14-15 years, on average). Most were males. No subject suffered a medical condition that could impair neurocognition.

Significant differences between smoking and nonsmoking heavy drinkers were detected on the Wisconsin Card Sorting Test (WCST), computerized version, reflecting executive function; and on the Fregly-Graybiel Ataxia Battery, reflecting balance. …