Neuropsychological deficits in sober alcoholics: influences of chronicity and recent alcohol consumption.

Background: The relationships between severity of neuropsychological (NP) deficits and quantity and duration of alcoholic drinking remain controversial. Eckardt et al. (1998) proposed that NP deficits can be observed only if chronicity of alcohol abuse equals or exceeds 10 years. In this study we tested the hypothesis of Eckardt et al. and reexamined the relationship of NP performance and alcohol consumption.

Methods: One hundred sixty-two alcoholics and 165 controls completed a NP test battery at least 3 weeks after the alcoholics attained sobriety. Chronicity varied from 4 to 9 years for 55 alcoholics and from 10 to 33 years for the remaining 107.

Results: Compared to controls, both groups of alcoholics were impaired on the Shipley Vocabulary and Abstraction tests and on two versions of the Digit Symbol test, but there was no difference between the two alcoholic groups on any measure. Regression analyses that controlled for age and education showed that chronicity predicted less than 0.5% of the variance on NP measures. By contrast, a measure of recent alcohol consumption, the Quantity-Frequency Index, contributed significantly (approximately 5% of the variance) to the prediction of alcoholics' NP performance.

Conclusions: These data provide weak support for a dose effect relationship between degree of NP impairment and level of alcoholic drinking in the past 6 months but no evidence for an influence of chronicity.