Decreased Cognitive Function As Related to Alcohol and Nicotine Consumption over an 11 Year Interval in Middle Age: A Longitudinal Study with a Community High Risk Sample

Alcoholism is associated with cognitive dysfunction and at least clinically is considered to be the causal agent responsible for the dysfunction. However, it has been difficult to parse whether the cognitive deficits precede alcoholism or whether the alcohol use causes brain damage which leads to cognitive impairment.

The current study measured cognitive functioning and alcohol use prospectively over a period of 11 years, in a sample of families enriched for known heavy drinking by the men. Therefore, we were able to control for pre-existing cognitive functioning and examine the effects of level of consumption over that interval.

Families were recruited based on the father’s alcoholism, with mother’s drinking free to vary. In addition, a control sample of families was recruited from the same neighborhoods as the families with father alcoholism. The latter group was generally similar in socioeconomic status and social functioning with the exception that their levels of alcohol consumption did not reach clinical levels. For the current study, 67 men and 76 women had measures of cognitive functioning available at the 2 time points (mean age of 41.7 and 52.8 years respectively). Cognitive functioning was assessed with the Microcog: Assessment of Cognitive Functioning, Short Form, which measures attention/mental control, memory, reasoning/calculation and spatial processing. The proficiency score, an overall measure of accuracy and speed on each of the subtests was used as our cognitive functioning measure

For men, proficiency at Wave 2, controlling for proficiency at Wave 1, was predicted by maximum amount of alcohol consumed over the prior 3 year period (beta = -.38, p = .017). For women, this relationship was not significant (beta = .23, p = .34). Nicotine dependence also predicted a decrease in proficiency over this time period for men (beta = -1.9, p = .013) but not for women (beta = -.36, p = .60).

The results show a direct effect of use of alcohol and smoking over time on decreased cognitive functioning in middle-aged adults from a community sample. The lack of relationship among the women is likely attributable to their lower levels of alcohol consumption and smoking during this time interval.