The ALDH2*2 allele has been shown to be a protective factor against alcoholism in a normal population owing in part to the elevated blood level of acetaldehyde and its accompanying physiological discomforts after drinking alcohol. Despite the well-established link between the ALDH2*2 allele and the physiological discomforts after drinking, very little is known regarding the psychological expectancies of drinking among persons with alcoholism with different ALDH genotypes.
To determine whether there are differences in craving, alcohol consumption, and alcohol outcome expectancies between persons with alcoholism who have the ALDH2*1/*2 genotype and persons with alcoholism who have the ALDH2*1/*1 genotype.
Six outpatient alcohol treatment facilities in Taiwan.
Ninety-eight persons with alcoholism who met the DSM-IV criteria for current alcohol dependence.
Main Outcome Measures
Alcohol Craving Scale, Form 90, and Alcohol Expectancies Scale scores.
Overall, the ALDH2*1/*2 group had lower negative alcohol outcome expectancies (F4,93 = 2.43, P≤.05, ηp2 = 0.10). Specifically, they had fewer expected negative outcomes in the social or interpersonal domain (P<.05) and the emotional and physical domain (P≤.005) than did the ALDH2*1/*1 group. Moreover, the ALDH2*1/*2 group had higher positive alcohol outcome expectancies (F7,90 = 2.36, P<.05, ηp2 = 0.16), and they had more expected positive outcomes in the relaxation and tension reduction domain (P<.05). The 2 groups did not differ in alcohol craving (P = .61) or consumption (P = .11).
Although the ALDH2*2 allele has been associated with negative physiological responses in normal samples in past research, the psychological expectancies of drinking are more positive and less negative for persons with alcoholism who have the ALDH2*1/*2 genotype. A role of acetaldehyde is implied in these effects, which seem to override the usual discomfort effects associated with protection against alcohol drinking. Future studies are needed to assess alcohol outcome expectancies at different phases of alcohol dependence and to evaluate the concurrent relationships of blood levels of acetaldehyde with physiological and psychological outcomes among persons with alcoholism who have different ALDH genotypes.