Hypersensitivity to acetaldehyde-protein adducts.

Acetaldehyde, the first product in the metabolism of ethanol, is known to condense with plasma proteins, forming stable adducts. We have previously shown that these adducts can be recognized as foreign by the immune system. In the present study the existence of type I hypersensitivity-mediating antibodies against these adducts was investigated in humans and in animals. Immunization of mice with acetaldehyde-protein condensates, followed by adoptive transfer of splenocytes, led to the production of IgE anti-acetaldehyde adducts. A monoclonal IgE antibody was obtained by the hybridization technique. This antibody recognized acetaldehyde adducts, independently of the carrier protein used, indicating that the acetaldehyde moiety behaves as a hapten. The affinity of the antibody for the acetaldehyde adduct of polylysine was 7 orders of magnitude higher than that for polylysine. Passive immunization by intradermal or intravenous administration of this monoclonal antibody to rats rendered the animals hypersensitive to acetaldehyde-protein conjugates, as shown by marked anaphylaxis. A study was conducted to determine the existence of naturally occurring hypersensitivity reactions to alcohol in > 1000 non-Oriental individuals. A prevalence of severe hypersensitivity reactions of 0.46% was found. The reactions were severe enough to deter these individuals from consuming all types of alcoholic beverages. Individuals presenting such reactions had significantly elevated levels of circulating anti-acetaldehyde-protein IgE antibodies.

The reliability of alcohol abusers' self-reports of drinking and life events that occurred in the distant past.

This study investigated the test-retest reliability of 69 alcohol abusers' current reports about their past (approximately 8 years prior to interview) drinking behavior and life events. Drinking behavior was assessed by the Lifetime Drinking History (LDH) questionnaire and life events were assessed using the Recent Life Changes Questionnaire (RLCQ). Reliability coefficients for LDH variables were generally moderate to high (r = .52 to .81). Using empirical criteria, the diagnostic power of the two LDH interviews to classify correctly subjects as either having had or not having had a drinking problem was quite high. The reliability coefficient for the RLCQ was r = .85 and 91.7% of the identified events were reported in both interviews. Similarly high test-retest reliabilities and individual event agreement rates were obtained for the six homogeneous subscales of the RLCQ. Subjects were also asked why they had given inconsistent answers to life events questions in the two interviews. Inconsistencies often resulted from errors in the temporal placement of events or from misunderstanding items, rather than from failure to recall an event; this suggests that some sources of error in recalling life events can be reduced. It is concluded that alcohol abusers' reports of drinking and life events occurring many years prior to the date of interview are generally reliable. This finding is consistent with previous studies showing high test-retest reliabilities for reports of recent drinking and related events.

Antibodies against acetaldehyde-modified protein epitopes in human alcoholics.

Acetaldehyde, the primary metabolite of ethanol, binds covalently to proteins forming condensation products which have been recently shown to be immunogenic. To assess whether an antibody response against acetaldehyde-modified protein epitopes is associated with alcoholic liver disease, the serum immunoreactivity against proteins modified in vitro by acetaldehyde and against the corresponding unmodified proteins was measured by an enzyme-linked immunosorbent assay in 58 alcoholics with varying degrees of liver damage. Alcoholics showed significantly higher titers against protein-acetaldehyde conjugates than against the unmodified protein, independent of the nature of the carrier protein. The highest titers occurred in alcoholic hepatitis patients. Sera of patients with chronic hepatitis of nonalcoholic origin and of healthy controls also reacted with acetaldehyde conjugates, but their titers were significantly lower than those in alcoholic hepatitis patients. Our data support the idea that binding of acetaldehyde to proteins in humans generates antigenic determinants which trigger a corresponding immune response against such epitopes and suggest that this humoral immune response may be implicated in autoantibody formation and liver damage associated with excessive alcohol consumption.

Effect of television programming and advertising on alcohol consumption in normal drinkers.

The drinking behavior of 96 male normal drinking college students was assessed after they viewed a videotape of a popular prime-time television program complete with advertisements. Different versions of the videotape were used to evaluate the effects of a television program with and without alcohol scenes as crossed with the effects of three different types of advertisements (i.e., beer, nonalcoholic beverages and food). After viewing the videotape, the subjects, who were led to believe that they were participating in two separate and unrelated sets of experimental procedures, were asked to perform a taste rating of light beers, which actually provided an unobtrusive measure of their alcohol consumption. The results provided no support for the widely held assumption that drinking scenes in television programs or televised advertisements for alcoholic beverages precipitate increased drinking by viewers. This finding, however, must be considered in the context of the laboratory setting of the study, and thus may not generalize to real-life television viewing. Further research in this area is clearly needed, including an evaluation of the effects of television program content and advertisements on other populations (e.g., alcohol abusers).

The reliability of a timeline method for assessing normal drinker college students' recent drinking history: utility for alcohol research.

The test-retest reliability of male (n = 40) and female (n = 40) college students' reports of recent drinking behavior was evaluated using a timeline (TL) procedure. The students also completed a quantity-frequency (QF) questionnaire (Cahalan, Cisin, & Crossley, 1969) often used to categorize subjects' drinking histories in alcohol research studies. The TL-derived data were found to have generally high reliability (usually r's greater than or equal to .87) for both males and females, with males having slightly higher reliabilities overall. Subjects were classified into drinker categories based on the QF questionnaire answers, and the resulting groups were compared using their TL-derived data on quantity, frequency, and quantity X frequency (mean number of drinks per drinking day) measures of drinking. The drinking behavior of subjects (as assessed by the TL) had great variability within the QF categories, and there was extensive overlap between subjects classified by the QF method as heavy, moderate and light drinkers. Thus, QF categorization provides a relatively insensitive measure of individual differences in drinking behavior as compared to TL-derived data. The TL method also can be used to generate a variety of potentially useful dependent variables, whereas the QF method generates a single variable.

The effect of alcohol on memory for feelings: does it really help users to forget?

In an innovative piece of research, Cowan (Cowan, J. D. Testing the escape hypotheses. Alcohol helps users to forget their feelings. J. Nerv. Ment. Dis., 171: 40-48, 1983) purports to have found that alcohol helps users to forget their feelings by impairing their ability to retrieve specific emotional states (i.e., reproduce particular mood ratings) originally experienced (rated) 48 hours earlier. Close inspection of Cowan's procedure and memory measures reveals, however, no basis for such a finding. Since his subjects rated their emotions on each of three occasions in addition to the one to be remembered and even reported virtually the same moods on each occasion, Cowan's memory test results were not unique to the intended target memories from 48 hours earlier but may have derived instead from any time at which mood was assessed, including just minutes before the memory test itself. To highlight the problems of interpretation encountered in this design, an alternative analysis of Cowan's data is offered, suggesting that alcohol may enhance, rather than impair, memory for feelings. The implications of that result for alcohol abuse are quite different from those proposed by Cowan, or by the "escape" hypotheses that he was trying to test.

Treatment of substance abuse by relaxation training: a review of its rationale, efficacy and mechanisms.

The efficacy of relaxation training as a treatment for alcohol and drug abuse is reviewed, and directions for future research derived. Such use of relaxation procedures, notably progressive muscular relaxation and meditation, has been widespread and is premised on the assumptions that substance abuse is causally linked to anxiety and that anxiety can be reduced by relaxation training. However, the evidence suggests that such precipitating anxiety is limited to interpersonal-stress situations involving diminished perceived personal control over the stressor, and that alcohol and other drugs are often consumed for their euphoric rather than tranquilizing effects. Consequently, the empirical support for the effectiveness of relaxation training as a treatment for substance abuse in general is equivocal. As well, the existing outcome studies suffer from numerous methodological and conceptual inadequacies. In cases of demonstrated effectiveness, increased perceived control is a more plausible explanation than is decreased anxiety.