Light to moderate alcohol intake protects heart by curbing stress signalling in the brain
USA: A new study published in the Journal of the American College of Cardiology has shed light on why light to moderate alcohol consumption may be tied to a lowered risk of CVD (cardiovascular disease).
The study revealed that light to moderate alcohol consumption is associated with lowered risk of MACE (major adverse cardiovascular events) partly mediated by reduced stress signalling in the brain. The most pronounced benefit of light to moderate drinking concerning MACE was seen among people with a history of anxiety, a condition associated with higher stress signalling in the brain.
The researchers reported, "that an increased cancer risk counterbalanced the apparent CVD benefits of light to moderate drinking." They showed that light to moderate alcohol consumption was associated with more significant decreases in MACE risk among people with a history of anxiety (HR, 0.60 versus HR, 1.78).
Chronic stress is linked with MACE via increased stress-related neural network activity (SNA). Light/moderate alcohol consumption (ACl/m) is reported to be associated with lower MACE risk, but there is no clarity on the mechanism behind it. To clarify the same, Kenechukwu Mezue, Yale School of Medicine, New Haven, Connecticut, USA, and colleagues aimed to evaluate whether the association between ACl/m and MACE is mediated by decreased SNA.
The study included people in the Mass General Brigham Biobank who completed a health behaviour survey. A subset underwent 18F-fluorodeoxyglucose PET (positron emission tomography), enabling SNA assessment. Alcohol consumption was classified as none/minimal, light/moderate, or high (<1, 1-14, or >14 drinks/week, respectively).
The authors reported the following findings:
- Of 53,064 participants (median age 60 years, 60% women), 23,920 had no/minimal alcohol consumption and 27,053 ACl/m.
- Over a median follow-up of 3.4 years, 1,914 experienced MACE. ACl/m (versus none/minimal) associated with lower MACE risk (HR: 0.786) after adjusting for cardiovascular risk factors. In 713 participants with brain imaging, ACl/m (versus none/minimal) was associated with decreased SNA (standardized beta −0.192).
- Lower SNA partially mediated the beneficial effect of ACl/m on MACE.
- ACl/m is associated with more significant decreases in MACE risk among individuals with (versus without) prior anxiety (HR: 0.60 versus 0.78).
"Low to moderate alcohol is associated with reduced MACE risk, in part, by lowering the activity of a stress-related brain network known for its link with cardiovascular disease," the researchers wrote. "Given alcohol's potential health detriments, new interventions with similar effects on SNA are required."
Reference:
The study, "Reduced Stress-Related Neural Network Activity Mediates the Effect of Alcohol on Cardiovascular Risk," was published in the Journal of the American College of Cardiology. DOI: https://www.jacc.org/doi/10.1016/j.jacc.2023.04.015
