Study reveals that wine consumption has an inverse relationship with cardiovascular health

In a recent study published in the nutrients Journal, researchers sought to understand the association between wine consumption and cardiovascular mortality, cardiovascular disease (CVD), and coronary heart disease (CHD).

The researchers conducted a systematic review and meta-analysis using longitudinal studies, including cohort and case-control studies retrieved from multiple databases, which they searched from inception to March 2023.

Study: Association between wine consumption with cardiovascular disease and cardiovascular mortality: a systematic review and meta-analysis. Image Credit: Alefat/Shutterstock.com

Background

Cardiovascular diseases account for a high proportion of deaths globally, with CVD-related deaths rising to nearly 18 million in 2017, with ischemic heart disease (IHD) causing almost half of deaths.

A previous meta-analysis suggested a J-shaped relationship between wine consumption and cardiovascular events, and that moderate wine consumption promoted better cardiovascular health.

A positive effect of wine on cardiovascular disease was first reported in 1979, when researchers also claimed that different components of wine exert protective effects against pathologies, such as coronary heart disease, mortality associated with coronary disease, and cancers, such as oral cancer. .

Furthermore, studies have suggested that dealcoholized wines (in the absence of ethanol) protect against thrombosis as they retain antioxidant effects.

Light or moderate alcohol consumption positively affects general health; for example, it acts on high-density lipoprotein cholesterol to prevent atherosclerosis, reduces the incidence of IC, and helps with the prognosis of people at increased risk of coronary complications leading to myocardial infarction.

Excessive alcohol consumption, by contrast, causes more than 200 diseases, making it one of the leading causes of death globally, that is, up to three million deaths annually. The consumption of high doses of alcohol also increases the risk of suicide, according to psychiatrists.

Alcohol interacts with multiple drugs, altering their metabolism or one’s own. Decreased alcohol metabolism could lead to increased blood alcohol levels. For example, a component of wine, resveratrol, interacts with certain drugs and modifies their metabolism.

Polyphenols from the non-flavonoid family present in red wine, like tannins, provide multiple benefits for cardiovascular health. It is also anti-inflammatory, antioxidant, and antimutagenic. However, all cardiologists agree that light or moderate alcohol consumption has a positive effect on cardiovascular health, while excessive alcohol consumption increases the risk of mortality from coronary heart disease, cancer, etc.

Mendelian randomization (MR) approaches looked at the effects of alcohol consumption on cardiovascular disease from a genetic point of view and found a much lower risk of cardiovascular disease in carriers of the alcohol dehydrogenase 1B (ADH1B) gene when they consumed less alcohol.

Similarly, studies have shown a positive effect of wine intake on non-fatal CHD, and beer consumption poses an increased risk of non-fatal stroke. Based on these observations, researchers have hypothesized that the components of wine could benefit health.

Since studies have never stratified these effects by type of alcohol, perhaps the researchers assumed that all alcoholic beverages had similar beneficial effects on heart health. However, scientific evidence is lacking as to which alcoholic beverages might be less harmful to CVD.

About the study

In the present study, the investigators explored the association between CVD incidence, cardiovascular mortality and CHD (all cardiovascular events) and wine consumption and attempted to elucidate its nature.

First, they compared the impact of wine on participants who drank wine versus those who did not. In addition, they examined whether characteristics of the study design and participant traits, such as age and smoking status, affected this association.

This systematic review and meta-analysis included studies with subjects older than 18 years. The exposure and outcome of the included studies were wine consumption and cardiovascular events, respectively.

The team assessed the risk of bias in the cohort studies using the quality assessment tool designed by the US National Heart, Lung, and Blood Institute. They used another similar tool to assess the risk of bias in case-control studies.

Finally, two independent reviewers rated the cumulative risk of bias of each study as good, fair, or poor; and found that the overall risk of bias for each included study was 100%.

Studies with larger sample sizes were included in the meta-analysis. They calculated relative risk (RR) and odds ratios (ORs) for the correlation between wine consumption and cardiovascular events and converted hazard ratios (HRs) reported in some studies into RRs.

The team also calculated pooled RRs for the effect of wine consumption on the risk of CHD, CVD, and cardiovascular mortality using the DerSimonian and Lair random-effects models. Finally, the team used Egger’s test to show evidence of publication bias for the association between CVD and wine consumption.

Results

After an extensive search for research studies, the authors retrieved 7,042 articles from nine countries with 1,443,245 subjects and a cumulative follow-up period of between four and 25 years. However, the final analytical set for this systematic review and meta-analysis comprised 25 and 22 studies, respectively. In addition, there were four case-control studies and 21 cohort studies.

Regarding cardiovascular events, seven, 13, and seven studies reported CVD, CHD, and cardiovascular mortality, respectively. Many studies did not report the amount of wine consumed; therefore, the researchers were unable to determine its effect.

The current review and meta-analysis added to previous evidence of an inverse association between wine consumption and three cardiovascular events evaluated in this study.

Importantly, the average age of the participants, the proportion of women, the length of follow-up, or smoking status did not affect this association. Consequently, the pooled RRs for CHD, CVD, and cardiovascular mortality were 0.76, 0.83, and 0.73, respectively, all with 95% confidence intervals (CI).

Although the observed inverse association applied to red and white wine, variations in the strength of this association were attributable to different concentrations of some components.

Red wine has phenolic compounds, such as gallic acid, catechin and epicatechin (flavonols), which give it antioxidant properties. They also reduce the oxidation of low-density lipoproteins (LDL), the risk of thrombosis, plasma and lipid peroxide.

In addition, the alcoholic components of wine reduce the risk of thrombosis and fibrinogen levels and induce the aggregation of collagen and platelets. Therefore, a higher consumption of red wine is more beneficial in combating CVD than other alcoholic beverages.

conclusions

The results of the current study confirmed existing data that moderate wine consumption is good for heart health. However, investigators should interpret these findings with caution. Increasing wine consumption could harm patients who are susceptible to alcohol due to age, pre-existing pathologies or medications.

Based on the findings of this review, wine could be part of other dietary recommendations. For example, the Mediterranean diet includes wine and recommends its use for its health benefits. However, studies need to assess and delineate the effect of wine consumption by type of wine.