Asian flushing: genetic and sociocultural factors of alcoholism among East asians

Associations between traumatic dental injuries due to violence and various drinking behaviors in Korea: A cross-sectional study

BACKGROUND AND AIM

Various patterns of alcohol consumption are associated with trauma and violence. The aim of this study was to assess the association between traumatic dental injuries (TDI) due to violence and different patterns of alcohol consumption in Korean adults.

MATERIALS AND METHODS

A cross-sectional study was conducted with representative sample of Korean adults. Among the total participants, 11.8% (6489/58,999) experienced TDI, and 0.9% (520/58,999) experienced TDI due to violence. The associations between various types of alcohol consumption (frequency of drinking, frequency of binge drinking, age of first drinking) and TDI due to violence were assessed using logistic regression analyses. We confirmed differences in the prevalence experience of TDI due to violence with various types of alcohol consumption by confounders (socioeconomic status).

RESULTS

All types of drinking (frequency of drinking, frequency of binge drinking, age of first drinking) were strongly associated with TDI due to violence. After adjusting for confounders, those who started drinking at the age of 18 or younger and drank 4 or more days a week (OR: 2.86, 95% CI: 1.68-4.88), those who started drinking at the age of 18 or younger and drank 3 days or less a week (OR: 2.37, 95% CI: 1.40-4.02), and those who started drinking at the age of 18 or younger and binge drinking at least once a week (OR: 3.18, 95% CI: 1.79-5.65) had higher prevalence of TDI due to violence compared to those with no alcohol drinking.

CONCLUSIONS

This study presents evidence of an association between various types of alcohol consumption and TDI due to violence in Korean adults. These findings suggest the necessity for policies aimed at reducing alcohol consumption, frequency of drinking, and access to drinking especially in adolescent to reduce the prevalence experience of TDI due to violence.

Molecular genetics of neuropsychiatric illness: some musings

Research into the genetic underpinnings of neuropsychiatric illness has occurred at many levels. As more information accumulates, it appears that many approaches may each offer their unique perspective. The search for low penetrance and common variants, that may mediate risk, has necessitated the formation of many international consortia, to pool resources, and achieve the large sample sizes needed to discover these variants. There has been the parallel development of statistical methods to analyse large datasets and present summary statistics which allows data comparison across studies. Even so, the results of studies on well-characterised clinical datasets of modest sizes can be enlightening and provide important clues to understanding these complex disorders. We describe the use of common variants, at multiallelic loci like TOMM40 and APOE to study dementia, weighted genetic risk scores for alcohol-induced liver cirrhosis and whole exome sequencing to identify rare variants in genes like PLA2G6 in familial psychoses and schizophrenia in our Indian population.

Interaction between ALDH2 rs671 and life habits affects the risk of hypertension in Koreans: A STROBE observational study

Aldehyde dehydrogenase-2 (ALDH2) is associated with the risk of hypertension, and the effects of lifestyle factors on blood pressure vary according to genotype. Among the Han Chinese, the risk of hypertension is lower in the group with the rs671 A allele than in the group with the G allele, and there is a significant association between the frequency of fried food consumption and hypertension. However, the A allele significantly increases the risk of hypertension with increased fried food intake. This study aimed to investigate the effect of the relationship between ALDH2 polymorphism and complex lifestyle habits (fried food consumption and exercise) on hypertension.rs671 polymorphisms of ALDH2 were examined using Korean genome and epidemiology data from 8157 hypertensive cases and 9550 controls. Further, we investigated whether the A allele is protective against hypertension in Koreans and explored the effect of the combination of fried food intake and exercise habits on hypertension by genotype.The genotype frequencies of rs671, which is specific to East Asia, were 2.51% AA, 26.66% GA, and 70.83% GG in the Korean population. The group with inactive aldehyde dehydrogenase-2 had a low odds ratio [OR = 0.75 (95% CI:0.69-0.80), P = 4.35 × 10-14] of hypertension, and low metabolism of acetaldehyde. Subjects carrying the A allele exhibited an increased risk of hypertension with increased fried food intake without exercise [OR = 2.256 (95% CI:1.094-4.654), P = .028].ALDH2 polymorphism and complex lifestyle habits (fried food consumption and exercise) are associated with the risk of hypertension. Further, the A allele is associated with a low risk of hypertension, but it increases the risk of hypertension as fried food intake without exercise increases.

Race- and sex-specific association between alcohol consumption and hypertension in 22 cohort studies: A systematic review and meta-analysis

BACKGROUND AND AIMS

The alcohol-hypertension relation has been well documented, but whether women have protective effect or race and type of beverage consumed affect the association remain unclear. To quantify the relation between total or beverage-specific alcohol consumption and incident hypertension by considering the effect of sex and race.

METHODS AND RESULTS

Articles were identified in PubMed and Embase databases with no restriction on publication date. Pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated by random effects models. Restricted cubic splines were used to model the dose-response association. This study involved 22 articles (31 studies) and included 414,477 participants. The hypertension risk was different among liquor, wine, and beer at 5.1-10 g/d of ethanol consumption (P_{-across subgroups} = 0.002). The hypertension risk differed between men (RR: 1.14, 95% CI: 1.07, 1.20) and women (RR: 0.98, 95% CI: 0.89, 1.06) at 10 g/d (P_{-across subgroups} = 0.005). We found a linear alcohol-hypertension association among white (P-_linearity = 0.017), black people (P-_linearity = 0.035), and Asians (P-_linearity<0.001). With 10 g/d increment of consumption, the RRs for hypertension were 1.06 (95% CI: 1.04, 1.08), 1.14 (95% CI: 1.01, 1.28), and 1.06 (95% CI: 1.01, 1.10) for Asians, black, and white people, respectively.

CONCLUSION

Sex modifies the alcohol-hypertension association at low level of alcohol consumption and we did not find evidence of a protective effect of alcohol consumption among women. Black people may have higher hypertension risk than Asians and white people at the same ethanol consumption.

Aldehyde Dehydrogenase, Liver Disease and Cancer

Acetaldehyde dehydrogenase 2 (ALDH2) is the key enzyme responsible for metabolism of the alcohol metabolite acetaldehyde in the liver. In addition to conversion of the acetaldehyde molecule, ALDH is also involved in other cellular functions. Recently, many studies have investigated the involvement of ALDH expression in viral hepatitis, alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), liver fibrosis, and liver cancer. Notably, ALDH2 expression has been linked with liver cancer risk, as well as pathogenesis and prognosis, and has emerged as a promising therapeutic target. Of note, approximately 8% of the world's population, and approximately 30-40% of the population in East Asia carry an inactive ALDH2 gene. This review summarizes new progress in understanding tissue-specific acetaldehyde metabolism by ALDH2 as well as the association of ALDH2 gene polymorphisms with liver disease and cancer. New research directions emerging in the field are also briefly discussed.

Differences in the risk of mood disorders in patients with asthma-COPD overlap and in patients with COPD alone: a nationwide population-based retrospective cohort study in Korea

BACKGROUND

Although feelings of anxiety and depression are common in patients with chronic obstructive pulmonary disease (COPD), little is known about the estimates of their incidence in patients with asthma-COPD overlap (ACO), which has been described and acknowledged as a distinct clinical entity. We aimed to estimate the risk of depression and anxiety among patients with ACO and compare it with the risk among those with COPD alone in the general population.

METHODS

We conducted a nationwide population-based retrospective cohort study using the Korean National Sample Cohort database between 1 January, 2002, and 31 December, 2013. Patients who were diagnosed with COPD (International Classification of Diseases, 10th revision [ICD-10] codes J42-J44) at least twice and prescribed COPD medications at least once between 2003 and 2011 were classified into two categories: patients who were diagnosed with asthma (ICD-10 codes J45-J46) more than twice and at least once prescribed asthma medications comprised the ACO group, and the remaining COPD patients comprised the COPD alone group. Patients who had been diagnosed with depression or anxiety within a year before the index date were excluded. We defined the outcome as time to first diagnosis with depression and anxiety. Matched Cox regression models were used to compare the risk of depression and anxiety among patients with ACO and patients with COPD alone after propensity score matching with a 1:1 ratio.

RESULTS

After propensity score estimation and matching in a 1:1 ratio, the cohort used in the analysis included 15,644 patients. The risk of depression during the entire study period was higher for patients with ACO than for patients with COPD alone (adjusted hazard ratio, 1.10; 95% confidence interval, 1.03-1.18; P value = 0.0039), with an elevated risk in patients aged 40-64 years (1.21; 1.10-1.34; 0.0001) and in women (1.18; 1.07-1.29; 0.0005). The risk of anxiety was higher for patients with ACO than for patients with COPD alone (1.06; 1.01-1.12; 0.0272), with a higher risk in patients aged 40-64 years (1.08; 1.00-1.17; 0.0392); however, the risk was not significant when stratified by sex.

CONCLUSIONS

This population-based study revealed a higher incidence of depression and anxiety in patients with ACO than in patients with COPD alone.

Aldehyde Dehydrogenase (ALDH) 2 in Diabetic Heart Diseases

A major pathophysiological mechanism behind the development of diabetic heart diseases is oxidative stress mediated by toxic reactive aldehydes such as 4-hydroxynonenal (4HNE). Aldehyde dehydrogenase (ALDH) 2 is a mitochondrial enzyme that has been found to detoxify these deleterious aldehydes and thereby mitigate cardiac damage. Furthermore, its protective role in cellular signaling reverses aberrations caused by hyperglycemia, thereby protecting cardiac function. This chapter assesses the role of ALDH2 in diabetic heart diseases by examining preclinical studies where ALDH2 activity is perturbed in both decreased and increased directions. In doing so, issues in improving ALDH2 activity in select human populations are elucidated, and further research directions are discussed.

Genetic variants of ALDH2-rs671 and CYP2E1-rs2031920 contributed to risk of hepatocellular carcinoma susceptibility in a Chinese population

Objective

Acetaldehyde dehydrogenase 2 (ALDH2) and cytochrome P450 2E1 (CYP2E1) have been associated with hepatocellular carcinoma (HCC) susceptibility and prognosis. The polymorphisms ALDH2 rs671 and CYP2E1 rs2031920 are reportedly correlated with the prevalence of HCC in other countries. The aim of this study was to investigate associations between ALDH2 and CYP2E1, and HCC susceptibility in a population of Guangxi, southern China, an area with a high incidence of HCC.

Patients and methods

The study cohort included 300 HCC cases, 292 healthy controls for HCC susceptibility analysis, and another 20 HCC cases and 10 healthy controls for ascertainment. Genotyping was performed using the polymerase chain reaction-restriction fragment length polymorphism method.

Results

The study results demonstrated that mutant genotypes of ALDH2 (G/A and A/A) led to significant differences in HCC susceptibility, as compared with the wild genotype (G/G) with the same C1/C1 genotype in non-drinking individuals (adjusted P=0.010, OR=0.20, 95% CI=0.06–0.68). The mutant genotypes of CYP2E1 (C1/C2 and C2/C2) brought about significant differences in HCC susceptibility, as compared with the wild genotype (C1/C1) and the same G/G genotype (adjusted P=0.025, OR=0.42, 95% CI=0.20–0.90). Drinking plays a role in HCC susceptibility in the same G/G genotype individuals (adjusted P=0.004, OR=0.32, 95% CI=0.15–0.69), but had no impact when combined with CYP2E1 for analysis (all P>0.05).

Conclusion

These results suggest that the mutant genotypes of ALDH2 and CYP2E1 may be protective factors for HCC susceptibility in Guangxi province, China.

Analysis of the Association of Nonsynonymous Polymorphisms in ADH Genes with Hazardous Drinking in HIV-1-Positive Individuals

BACKGROUND

Hazardous drinking (HD) is a serious health problem in people infected with human immunodeficiency virus type 1 (HIV-1). Single nucleotide polymorphisms (SNPs) in alcohol dehydrogenase (ADH) genes have been associated with HD in different populations, but there were no data about this in HIV-1-positive individuals. This study investigated the association of 4 nonsynonymous SNPs in ADH genes (Arg48His and Arg370Cys in ADH1B gene; Arg272Gln and Ile350Val in ADH1C gene) with HD in people living with HIV-1.

METHODS

This case-control study included 365 HIV-1-positive individuals (121 with HD and 244 without HD). Sociodemographic variables were collected with a standardized individual questionnaire. HD (score ≥8) and binge drinking (BD) (drinks on the same occasion ≥5) were detected with the Alcohol Use Disorders Identification Test. The 4 SNPs were genotyped by the polymerase chain reaction-restriction fragment length polymorphism method. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated using logistic regression analysis. The Bonferroni correction was used (considering the 4 SNPs studied).

RESULTS

There were no significant differences in the frequencies of Arg370Cys, Arg272Gln, and Ile350Val polymorphisms between HD cases and controls. Otherwise, Arg/His genotype (rs1229984) in ADH1B gene showed a protective effect against HD (aOR = 0.36; 95% CI: 0.14 to 0.90) and BD (aOR = 0.49; 95% CI: 0.21 to 0.95). Nevertheless, these differences were no longer significant after Bonferroni correction.

CONCLUSIONS

The results of this study suggest a possible effect of the Arg48His genotype on the protection against HD in HIV-1-positive individuals.