Effect of the ALDH2 Variant on the Prevalence of Atrial Fibrillation in Habitual Drinkers

BACKGROUND: Alcohol—a risk factor for atrial fibrillation (AF)—is metabolized by aldehyde dehydrogenase 2 (ALDH2). Dysfunctional alleles of ALDH2 (ALDH2-deficient variants) are prevalent among East Asians. OBJECTIVES: Because the prevalence of AF is estimated to be high in ALDH2-deficient variant carriers, we investigated the correlation between AF and ALDH2-deficient variant carriers, including the association with habitual alcohol consumption. METHODS: A total of 656 consecutive patients were included in this investigation. ALDH2 genotypes were divided into ALDH2 homozygous wild-type (∗1/∗1), ALDH2 heterozygous-deficient allele (∗1/∗2), and ALDH2 homozygous-deficient allele (∗2/∗2). Multivariate analyses were applied to determine the correlation between ALDH2 genotype and AF. RESULTS: ALDH2∗1/∗2 and ALDH2∗2/∗2 carriers who were ALDH2-deficient variant carriers comprised 199 (30.3%) and 27 (4.1%) patients, respectively. Among these patients, the proportions of habitual alcohol consumption were 26.1% and 0%, respectively. Multivariate analysis revealed that ALDH2∗1/∗2 itself was not a risk factor for AF (odds ratio [OR]: 1.28; P = 0.21). However, habitual alcohol consumption in ALDH2∗1/∗2 carriers was an independent risk factor of AF (OR: 4.13; P = 0.001). Contrary to expectations, ALDH2∗2/∗2 itself had a lower incidence of AF among other risk factors (OR: 0.37; P = 0.03). CONCLUSIONS: Although the ALDH2∗1/∗2 itself was not associated with AF, ALDH2∗1/∗2 carriers with habitual alcohol consumption could experience AF because of slow alcohol metabolism. In contrast, ALDH2∗2/∗2 itself had a lower incidence of AF. This might be related to the absence to habitual alcohol consumption in ALDH2∗2/∗2 carriers because of the negligible activity of ALDH2. Thus, abstaining from alcohol consumption might prevent the development of AF in patients who are ALDH2∗1/∗2 carriers.