Cognitive components of frontal lobe function in alcoholics classified according to Lesch's typology

This study examined the frontal lobe cognitive function and the mental state among patients with different types of alcohol dependence according to Lesch's typology.

The frontal assessment battery (FAB) and the mini-mental status examination (MMSE) were given to 170 patients with alcoholism from a Brazilian outpatient service classified by Lesch's typology and to 40 non-alcoholic controls matched for age, gender, socio-demographic characteristics and education.

Of the alcoholic sample, 21.2% were classified as Type I, 29.4% as Type II, 28.8% as Type III and 20.6% as Type IV. Alcoholics showed significantly lower overall scores on the MMSE and the FAB as compared to non-alcoholic subjects. Type IV alcoholics had lower MMSE and FAB overall scores as compared to non-alcoholic controls and also to all other types of alcoholic subjects. However, Type II and III subjects with alcoholism also had lower overall FAB scores, but not overall MMSE scores, as compared to non-alcoholic controls. The FAB subsets of motor programming, sensitivity to interference and inhibitory control were significantly reduced in Types II, III and IV alcoholics as compared to non-alcoholic subjects, but only motor programming remained impaired in Type IV alcoholics with preserved mental function.

Executive dysfunctions in alcohol dependence seem to vary depending upon the type of alcoholism. Therefore, the determination of clinical type of alcohol dependence by applying Lesch's typology, along with brief mental state and frontal function examinations, is of clinical relevance in the examination of alcoholics and provides significant clues for more directed forms of alcohol dependence treatment.