Alcohol intake and nonfatal acute myocardial infarction in Japan

A burden of proof study on alcohol consumption and ischemic heart disease

Cohort and case-control data have suggested an association between low to moderate alcohol consumption and decreased risk of ischemic heart disease (IHD), yet results from Mendelian randomization (MR) studies designed to reduce bias have shown either no or a harmful association. Here we conducted an updated systematic review and re-evaluated existing cohort, case-control, and MR data using the burden of proof meta-analytical framework. Cohort and case-control data show low to moderate alcohol consumption is associated with decreased IHD risk - specifically, intake is inversely related to IHD and myocardial infarction morbidity in both sexes and IHD mortality in males - while pooled MR data show no association, confirming that self-reported versus genetically predicted alcohol use data yield conflicting findings about the alcohol-IHD relationship. Our results highlight the need to advance MR methodologies and emulate randomized trials using large observational databases to obtain more definitive answers to this critical public health question.

Dietary Patterns, Alcohol Consumption and Risk of Coronary Heart Disease in Adults: A Meta-Analysis

Previous studies reported the potential associations between dietary patterns and the risk of coronary heart disease (CHD) in adulthood, however a consistent perspective has not been established to date. Herein, we carried out this meta-analysis to evaluate the associations between dietary patterns and the risk of CHD. MEDLINE and EBSCO were searched for relevant articles published up to April 2015. A total of 35 articles (reporting 37 original studies) met the inclusion criteria and were included in the present meta-analysis. The decreased risk of CHD was shown for the highest compared with the lowest categories of healthy/prudent dietary patterns (odds ratio (OR) = 0.67; 95% confidence interval (CI): 0.60, 0.75; p < 0.00001) and alcohol consumption (OR = 0.68; 95% CI: 0.59, 0.78; p < 0.00001). There was evidence of an increased risk of CHD in the highest compared with the lowest categories of the unhealthy/Western-type dietary patterns (OR = 1.45; 95% CI: 1.05, 2.01; p = 0.02). The results of this meta-analysis indicate that different dietary patterns may be associated with the risk of CHD.

The cardioprotective association of average alcohol consumption and ischaemic heart disease: a systematic review and meta-analysis

AIMS

  Most, but not all, epidemiological studies suggest a cardioprotective association for low to moderate average alcohol consumption. The objective was to quantify the dose-response relationship between average alcohol consumption and ischaemic heart disease (IHD) stratified by sex and IHD end-point (mortality versus morbidity).

METHODS

  A systematic search of published studies using electronic databases (1980-2010) identified 44 observational studies (case-control or cohort) reporting a relative risk measure for average alcohol intake in relation to IHD risk. Generalized least-squares trend models were used to derive the best-fitting dose-response curves in stratified continuous meta-analyses. Categorical meta-analyses were used to verify uncertainty for low to moderate levels of consumption in comparison to long-term abstainers.

RESULTS

  The analyses used 38,627 IHD events (mortality or morbidity) among 957,684 participants. Differential risk curves were found by sex and end-point. Although some form of a cardioprotective association was confirmed in all strata, substantial heterogeneity across studies remained unexplained and confidence intervals were relatively wide, in particular for average consumption of one to two drinks/day.

CONCLUSIONS

  A cardioprotective association between alcohol use and ischaemic heart disease cannot be assumed for all drinkers, even at low levels of intake. More evidence on the overall benefit-risk ratio of average alcohol consumption in relation to ischaemic heart disease and other diseases is needed in order to inform the general public or physicians about safe or low-risk drinking levels.

Ischemic heart disease mortality and morbidity rates in former drinkers: a meta-analysis

Current abstainers from alcohol have been identified as an inadequate reference group in epidemiologic studies of the effects of alcohol, because inclusion of former drinkers might lead to overestimation of the protective effects and underestimation of the detrimental effects of drinking alcohol. The authors' objective in the current study was to quantify this association for ischemic heart disease (IHD). Electronic databases were systematically searched for relevant case-control or cohort studies published from 1980 to 2010. Thirty-eight articles fulfilled the inclusion criteria, contributing a total of 5,613 IHD events and 12,097 controls among case-control studies and 1,387 events with combined endpoints and 7,183 events stratified by endpoint among 232,621 persons at risk among cohort studies. Pooled estimates for the subset stratified by sex and endpoint showed a significantly increased risk among former drinkers compared with long-term abstainers for IHD mortality ( among men; relative risk = 1.25, 95% confidence interval: 1.15, 1.36; among women relative risk = 1.54, 95% confidence interval: 1.17, 2.03). For IHD morbidity, the estimates for both sexes were close to unity and not statistically significant. Results were robust in several sensitivity analyses. In future studies, researchers should separate former drinkers from the reference category to obtain unbiased effect estimates. Implications for the overall beneficial and detrimental effects of alcohol consumption on IHD are discussed below.

Lack of association between water hardness and coronary heart disease mortality in Japan

BACKGROUND

Elevated levels of water hardness are related to lower mortality from coronary heart disease (CHD) in different populations. This ecologic study assessed whether water hardness is related to lower mortality from CHD in Osaka Prefecture, with 44 municipalities, Japan.

METHODS

The mortality rate from CHD per municipality was calculated based on the number of coronary deaths and midyear population in 1995. Values for water hardness in each of the municipalities were estimated based on the yearly amount of water supply per source and the yearly average of water hardness for each source in 1997. Multiple logistic regression analysis was used to control socioeconomic status and health care status in each municipality.

RESULTS

In males, after adjustment for age, an inverse dose-response relationship between water hardness and mortality from CHD was significant (P for linear trend=0.004). However, this relationship virtually disappeared after further adjusting for socioeconomic status and health care status. In females, there was no material association between water hardness and coronary mortality.

CONCLUSIONS

This study provides no evidence that water hardness is preventive against mortality from CHD in Japan.

Alcohol consumption and severity of angiographically determined coronary artery disease in Japanese men and women

The relation of alcohol consumption to the severity of coronary atherosclerosis was examined among 323 men and 220 women who underwent coronary arteriography. Severity of coronary atherosclerosis was assessed by the number of vessels obstructed > or =75% in diameter and Gensini's severity score. Alcohol consumption was divided into 5 categories in men (never, past, 1-24, 25-49, and > or =50 ml per day) and 3 categories in women (never, past, and current). Among men, odds ratios of severe stenosis (multiple-vessel disease or Gensini's score >15) decreased substantially and significantly in all current drinking categories but without dose-response effect. There was a weak, inverse association of current alcohol consumption with one-vessel disease, but not with moderate stenosis in terms of Gensini's score (< or =15). Past drinkers showed a fairly large, but statistically nonsignificant, decrease in the odds ratios of not only severe stenosis but also of moderate stenosis. Among women, current drinkers showed a small, statistically nonsignificant decrease in the risk of severe stenosis in terms of Gensini's score. These associations with alcohol use did not change after adjustment for known coronary risk factors. The present findings add to evidence that alcohol drinking confers protection against coronary atherosclerosis.

Risk factors for non-fatal acute myocardial infarction in middle-aged and older Japanese. Fukuoka Heart Study Group

It remains uncertain whether established risk factors for coronary heart disease in middle-aged persons can be generalized to elderly persons. Based on a case-control study, risk factors for nonfatal acute myocardial infarction (AMI) were assessed separately in middle-aged (40-64 years) and older (65-79 years) Japanese. Eligible cases were patients who were admitted to 22 collaborating hospitals for the first AMI between September 1996 and January 1998. Community controls were recruited by using the resident registers of the municipalities with individual matching by gender, year of birth (within 2 years), and proximity in residence. The present study used 384 sets of 384 cases and 656 controls. Smoking, hypertension, and angina pectoris were associated with an increased risk of AMI, and alcohol use and leisure-time exercise were related to a decreased risk of AMI in the elderly as well as in middle-aged persons. There was no apparent relation between body mass index and AMI in either middle-aged or older adults. Diabetes mellitus was significantly associated with an increased risk of AMI in older persons, but not in middle-aged persons. Hypercholesterolemia was related to an increased risk of AMI in middle-aged individuals alone. The findings suggest that risk factors for AMI in the elderly are generally similar to those of middle-aged persons, but provide no evidence that hypercholesterolemia in the elderly is an important risk factor.

Atherosclerosis in alcoholics

A cohort of alcoholics who underwent a medico-legal autopsy during a 5-year period was compared with non-alcoholic controls who did not differ from the alcoholics in selection criteria. The degree of atherosclerosis in the coronary arteries and the aorta was examined. Alcoholic men and old women had a significantly lower degree of atherosclerosis in the coronary arteries, while the opposite was found in young women. In the aorta there was no significant difference in the degree of atherosclerosis between alcoholics and controls in men. Alcoholic women generally had a lower degree of atherosclerosis in the aorta. The so-called U-shaped curve for the relationship between the daily alcohol intake and atherosclerosis is described together with some of the investigations on which it is based. There is much positive evidence for the U-shaped curve, although a causal association has not been proven as yet. The present results indicate a complex relationship, in which different confounding factors are likely to play a role.

Alcohol, hypertension, coronary disease and stroke

1. The association between alcohol and hypertension has been recognized for several years. 2. However, it remains a paradox that if alcohol does cause hypertension there is little convincing evidence that alcohol is related to the cardiovascular complications of hypertension such as strokes and heart attacks. The relationship between alcohol and strokes remains inconclusive and there is evidence that moderate alcohol consumption may be protective against heart attacks. 3. It is possible, therefore, that alcohol does not so much cause hypertension, but rather a rapidly reversible rise in blood pressure which does not cause cardiovascular damage. When managing hypertensive patients, however, relevant counselling can bring about a useful fall in blood pressure.