• Energy Research

Three hundred forty‐two male and female subjects from the Colorado Alcohol Research on Twins and Adoptees returned a mailed questionnaire that included the Eysenck Impulsivity‐Venturesomeness‐Empathy scales. These subjects had previously been tested in a procedure in which they were given a 0.8 g/kg dose of ethanol to bring their peak blood alcohol concentration (BAC) to near 0.10 g/dl, given topping doses to maintain this BAC over a 3‐hr period, and repeatedly tested on a battery of diverse physiological, psychomotor, perceptual speed, and mood measures. Impulsivity was significantly correlated with higher levels of self‐reported alcohol use and the occurrence of alcohol use problems in males, while both impulsivity and venturesomeness (sensation seeking) were significantly correlated with lessened motor impairment following alcohol use in males. These personality measures, however, were not significantly correlated with mood measures following initial alcohol dosing. Impulsivity and venturesomeness were uncorrelated with alcohol use and responses to alcohol in females, but as with males, impulsivity was related to the occurrence of alcohol use problems in females.

Multivariate path analysis was used to examine the etiologies of variation and covariation of flushing after alcohol use in nuclear families of Korean, Taiwanese, Japanese and Caucasian ancestries. Phenotypic variances and covariances were partitioned into familial (additive genetic and common family environment) and environmental components. Although alcohol consumption and flushing varied greatly among the different groups, familialities, estimated from components of mother, father and at least one child, were remarkably similar. The familialities for flushing were 0.48 for Japanese, 0.56 for Koreans and 0.35 for Taiwanese; flushing is infrequent in Caucasians and thus was not analyzed. Familialities were lower for consumption, but like flushing, were consistent across ethnic groups (Japanese, 0.27; Koreans, 0.24; Taiwanese, 0.15; Caucasians, 0.28). The genetic correlation between flushing and alcohol consumption was high. Thus, to the extent that flushing influences alcohol consumption, the covariance is most likely genetic.

The association of flushing (vasodilation, reddening of the skin) with the alcohol use of Asians and Asian-Americans is examined. Historical changes in alcohol use, recent secular changes in alcohol use, and marked differences in consumption among Asian populations and among Asian-Americans of the same national origins, as well as the lack of reduction of sex differences among flushers, indicate that flushing has little influence on alcohol consumption. Social, psychological, and cultural influences seem to be more adequate explanatory devices with regard to Oriental alcohol use.

Data were presented in a previous paper having to do with ethnic, sex, and generational differences in the flushing response to alcohol, the number of drinks required to evoke flushing, and family resemblances in flushing. Using a much largerN (1288 subjects; 245 families), the present report is of the same analyses, as well as analyses pertaining to the extent and duration of flushing, association of flushing with other symptoms, and degree to which flushing influenced drinking behavior. As in the previous paper, a distinction was made between fast (one drink or less to evoke flushing) and slow (two drinks or more to evoke flushing) flushing. Substantial ethnic differences were found in flushing. Highly significant family resemblances in flushing were also found, but these did not conform to a single-locus genetic model. Extent of flushing was significantly related to flushing type-fast vs. slow-but duration of flushing was not, nor were most other symptoms resulting from alcohol use. Fast vs. slow flushing may or may not involve differing genetic mechanisms (probably not, on the basis of data acquired and analyzed to date). However, the two flushing types appear to have different amounts of influence on drinking behavior. Regardless of flushing type, a substantial proportion of flushers does not eschew alcohol because of flushing or cease to drink once flushing occurs.

Thirty‐four subjects in the Colorado Alcohol Research on Twins and Adoptees (CARTA) were brought back between 30 to 60 days after their initial testing to be retested on all the CARTA procedures. As before, subjects were given a dose of ethanol (0.8 g/kg) calculated to bring their blood alcohol concentration (BAC) to near 0.10 g/dl. Additional doses were given at the end of each of the next 2 hr to maintain their BAC near peak for approximately 3 hr. During both testings, subjects' self‐reports of their emotional responses and perceived intoxication following alcohol dosing were only minimally correlated with their alcohol metabolism parameters and reported average level of alcohol use. Repeatabilities (test‐retest correlations) for subjects' self‐reports of positive affect and of intoxication following alcohol dosing were consistently high, in contrast to earlier reports of minimal repeatabilities for alcohol metabolism and responses to alcohol on physiological, motor coordination, reaction time, and perceptual speed measures. Tester ratings of the subjects' levels of intoxication were also moderately stable between the two testings.

Forty normal drinking males were recruited for a study of “responses to alcohol.” Following the completion of an alcohol use questionnaire that included measures of expectancies of alcohol effects, subjects were randomly assigned to either receive the actual 0.6 g/kg dose of ethanol to bring their peak blood alcohol concentration (BAC) to near 0.075 g/dl or to receive a placebo dose. Neither the subject nor the tester was aware of the condition to which the subject had been assigned. Prior to dosing and at repeated ½‐hr intervals following dosing, subjects were tested on a battery of motor coordination, perceptual speed, reaction time, and mood measures. Significant alcohol effects were found for several measures, but the only significant interaction of individual differences in expectancies of alcohol effects with alcohol dosing occurred for self‐perceived intoxication. Subjects who expected more disinhibition after alcohol dosing and who were administered alcohol reported more intoxication than those expecting less disinhibition, while no expectancy effect was found for subjects administered the placebo.

Due to the problem of correlation of errors inherent in the difference or ratio scores typically used to quantify individual differences in acute sensitivity and tolerance to alcohol, it is recommended that residual scores from regression analyses be used instead for such quantification. Conceptualizations of acute sensitivity and tolerance and problems with the reliability of change scores are also discussed.

Data from 42 male and 58 female subjects who participated in the Colorado Alcohol Research on Twins and Adoptees (CARTA) project were subjected to model‐fitting analyses. The aim of the present study was to use linear structural equation models to determine whether differences in previously measured psychomotor sensitivity to alcohol predict differences in self‐reported alcohol consumption over a 4‐year period. LISREL model‐fitting results indicate that, for male subjects, only rail walking insensitivity is predictive of alcohol use reported 2 years after their initial CARTA testing. For females, only hand steadiness sensitivity is predictive of alcohol use reported 2 years after their initial CARTA testing. The results for males support a hypothesis that would consider alcohol insensitive individuals at greater risk for alcohol abuse. The female results, however, would argue against such a hypothesis.With only one measure of sensitivity predicting alcohol use at only one out of four time points, in both men and women, the overall results suggest that our three measures of psychomotor sensitivity to alcohol are, in general, poor predictors of alcohol consumption in this sample.

Thirty-eight subjects in the Colorado Alcohol Research on Twins and Adoptees (CARTA) were brought back between 3 and 39 months after their initial testing to be retested on a shortened version of the standard CARTA procedures. As before, subjects were given a dose of ethanol (0.8 g/kg) calculated to bring their blood alcohol level (BAL) to near 100 mg/dl, but no topping doses were administered in the retests to maintain BALs near peak for 3 hours, as was done previously. Repeatability (test-retest correlation) for alcohol clearance rate was near zero, repeatability for time to peak BAL was 0.36 and that for peak BAL was 0.50. Repeatabilities of prealcohol baseline scores were generally high (median 0.55) for the shortened battery of physiological, motor coordination, perceptual speed and reaction time measures. Repeatabilities were near zero for sensitivity scores (median 0.02) and were low for acute tolerance scores (median 0.10) and perceived intoxication (median 0.27). These findings are highly consistent with an earlier report on repeatabilities of responses to alcohol over a 1-month time interval.