Factors Related to Maximum Number of Drinks in a 24-hour Period
In Chinese- and Korean- American College Students
J. Chen, S.E. Luczak, B. Trischler, J. Lam, J. Lee, S.H. Shea, T. Liang, & T.L. Wall
University of California, San Diego and Veterans Medical Research Foundation
Introduction
Ø The maximum number of drinks ever consumed
in a 24-hour period (Max Drinks) has been shown
to be a heritable trait in twin studies.
Ø Max Drinks is a single-item measure of lifetime
heavy drinking.
It is thought to reflect an
individual’s capacity to metabolize alcohol, and is
one of several variables that differentiate
individuals who develop alcohol dependence from
those who do not.
Ø The
primary pathway of alcohol metabolism
involves two different enzymes, see Figure 1. The
enzyme alcohol dehydrogenase (ADH) catalyzes
the first step of alcohol metabolism, and the
enzyme aldehyde dehydrogenase (ALDH) catalyzes
the second step.
Method
0
Participants
(52% female) Korean-American college students,
21 - 26 years of age.
Ø A blood sample from each participant was
Ø The SSAGA was used to determine participants
lifetime Max Drinks as well as the age and context
of the drinking occasion.
Data Analysis
Ø ANOVAs were conducted to determine if Max
Drinks was related to ethnicity and to the ALDH2
and ADH1B genes.
Results
8.8
10
9.3
12.2
15
was significantly associated with
Max Drinks in both Chinese and Koreans,
however, ADH1B*2 was not.
was significantly associated with Max
Drinks in both Chinese (F = 14.2, df = 2, p < .001)
and Koreans (F = 4.5, df = 2, p = .011).
Ø As
hypothesized, Chinese and Korean
individuals without ALDH2*2 alleles had the
highest average Max Drinks (8.8 and 12.2)
followed by those with one (6.2 and 9.3) and then
two (3.3 and 8.0) ALDH2*2 alleles, although in
Koreans only the difference between those with
no and two alleles was significant.
0
Chinese
Koreans
sknirD naeM
_____________________________________________________________________________________________________________________________________
5
0
ADH1B*1/2*1
ADH1B*1/2*2
5
5.6
10
10.4
11
11.1
Korean
7.7
Ø ADH1B*2
15
Males
14.6
Females
was not significantly associated
with Max Drinks in either ethnic sample: Chinese,
F=1.31 (2, 403), p = .271 Korean F=10.22 (2, 376),
p = .805.
Ø 9.1
participants had lower average Max
Drinks (7.4 vs. 11.2, t=7.6, p<.001) than Korean
participants.
% of participants reported their Max
Drinks occurred on their 21st birthday, but
neither ALDH2*2 or ADH1B*2 alleles was
associated with Max Drinks occurring on one's
21st birthday.
Ø Due to ethnic difference and the issue of
Ø Neither ALDH2*2 or ADH1B*2 was associated
Ø Chinese
population stratification, analyses were conducted
separately for Chinese and Korean participants.
individual’s alcohol intake (or capacity to drink),
thereby contributing to their overall lower risk
for developing alcohol dependence.
Ø Limitations to the study include the use of
self-report measures collected at one time point,
a volunteer sample, and a restricted age range.
This research was funded by NIH Grants: R01
AA11257, K02 AA00269, and K08 AA14265.
7.3
7.6
Chinese
Ø Previous studies have shown an association of
Ø These findings suggest ALDH2*2 lowers an
ADH1B*2/*2
15
9
which Max Drinks was consumed.
Acknowledgements
5.6
10
Ø Neither genotype was associated with age at
ADH1B
sknirD naeM
Max Drinks
college students were
significantly more likely to have an ALDH2*2
allele and had a lower average maximum number
of drinks ever consumed in a 24-hour than
Korean-American college students. Because of
these ethnic differences, analyses were
conducted separately for Chinese and Koreans.
Ø ALDH2*2
Ø ALDH2
to Korean American participants,
Chinese American participants were more likely to
have an ALDH2*2 allele (47% vs. 32%, x2 = 18.5, df
= 2, p < .001). ADH1B*2 allele prevalence did not
differ by ethnicity.
Primary Pathway of Alcohol Metabolism
ADH1B*2 alleles would have lower average Max
Drinks. We explored whether Max Drinks occurred
on one’s 21st birthday.
8
Ø Compared
Figure 1.
Ø We hypothesized individuals with ALDH2*2 and
5
genotyped at the ALDH2 and ADH1B loci.
ØBoth ADH1B*2 and ALDH2*2 alleles have been
ALDH2*2 with Max Drinks in Asian populations,
and ADH1B*2 has also been associated with Max
Drinks in Caucasians.
Ø Chinese-American
3.3
6.2
Data Collection
Ø ALDH2 is one of the forms of ALDH.
ALCOHOL
ACETALDEHYDE
ACETATE
Alcohol Dehydrogenase
Aldehyde Dehydrogenase
(ADH)
(ALDH)
_________________________________________________________________
Summary of Findings
Ø 406 (50% female) Chinese-American and 379
Ø ADH1B is one of the forms of ADH.
associated with reduced risk for alcohol
dependence.
Discussion
ALDH2
with age at which Max Drinks was consumed.