Young adults aged 15-34 years derive no significant health benefits from alcohol consumption, but moderate drinking may benefit the over-40 crowd, according to a new analysis.
The health risks and benefits of moderate alcohol consumption are complex and remain a hot topic of debate. The data suggest that small amounts of alcohol may reduce the risk of certain health outcomes over time, but increase the risk of others, wrote Dana Bryazka, MS, a researcher at the Institute for Health Metrics and Evaluation (IHME) at the University of Washington, Seattle, and colleagues, in a paper published in The Lancet.
"The amount of alcohol that minimizes health loss is likely to depend on the distribution of underlying causes of disease burden in a given population. Since this distribution varies widely by geography, age, sex, and time, the level of alcohol consumption associated with the lowest risk to health would depend on the age structure and disease composition of that population," the researchers wrote.
"We estimate that 1.78 million people worldwide died due to alcohol use in 2020," Bryazka said in an interview. "It is important that alcohol consumption guidelines and policies are updated to minimize this harm, particularly in the populations at greatest risk," she said.
"Existing alcohol consumption guidelines frequently vary by sex, with higher consumption thresholds set for males compared to females. Interestingly, with the currently available data we do not see evidence that risk of alcohol use varies by sex," she noted.
Methods and Results
In the study, the researchers conducted a systematic analysis of burden-weighted dose-response relative risk curves across 22 health outcomes. They used disease rates from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2020 for the years 1990-2020 for 21 regions, including 204 countries and territories. The data were analyzed by 5-year age group, sex, and year for individuals aged 15-95 years and older. The researchers estimated the theoretical minimum risk exposure level (TMREL) and nondrinker equivalent (NDE), meaning the amount of alcohol at which the health risk equals that of a nondrinker.
One standard drink was defined as 10 g of pure alcohol, equivalent to a small glass of red wine (100 mL or 3.4 fluid ounces) at 13% alcohol by volume, a can or bottle of beer (375 mL or 12 fluid ounces) at 3.5% alcohol by volume, or a shot of whiskey or other spirits (30 mL or 1.0 fluid ounces) at 40% alcohol by volume.
Overall, the TMREL was low regardless of age, sex, time, or geography, and varied from 0 to 1.87 standard drinks per day. However, it was lowest for males aged 15-39 years (0.136 drinks per day) and only slightly higher for females aged 15-39 (0.273), representing 1-2 tenths of a standard drink.
For adults aged 40 and older without any underlying health conditions, drinking a small amount of alcohol may provide some benefits, such as reducing the risk of ischemic heart disease, stroke, and diabetes, the researchers noted. In general, for individuals aged 40-64 years, TMRELs ranged from about half a standard drink per day (0.527 drinks for males and 0.562 standard drinks per day for females) to almost two standard drinks (1.69 standard drinks per day for males and 1.82 for females). For those older than 65 years, the TMRELs represented just over 3 standard drinks per day (3.19 for males and 3.51 for females). For individuals aged 40 years and older, the distribution of disease burden varied by region, but was J-shaped across all regions, the researchers noted.
The researchers also found that those individuals consuming harmful amounts of alcohol were most likely to be aged 15-39 (59.1%) and male (76.9%).
The study findings were limited by several factors including the observational design and lack of data on drinking patterns, such as binge drinking, the researchers noted. Other limitations include the lack of data reflecting patterns of alcohol consumption during the COVID-19 pandemic, and exclusion of outcomes often associated with alcohol use, such as depression, anxiety, and dementia, that might reduce estimates of TMREL and NDE.
However, the results add to the ongoing discussion of the relationship between moderate alcohol consumption and health, the researchers said.
"The findings of this study support the development of tailored guidelines and recommendations on alcohol consumption by age and across regions and highlight that existing low consumption thresholds are too high for younger populations in all regions," they concluded.
Consider Individual Factors When Counseling Patients
The takeaway message for primary care is that alcohol consumed in moderation can reduce the risk of ischemic heart disease, stroke, and diabetes, Bryazka noted. "However, it also increases the risk of many cancers, intentional and unintentional injuries, and infectious diseases like tuberculosis," she said. "Of these health outcomes, young people are most likely to experience injuries, and as a result, we find that there are significant health risks associated with consuming alcohol for young people. Among older individuals, the relative proportions of these outcomes vary by geography, and so do the risks associated with consuming alcohol," she explained.
"Importantly, our analysis was conducted at the population level; when evaluating risk at the individual level, it is also important to consider other factors such as the presence of comorbidities and interactions between alcohol and medications," she emphasized.
Health and Alcohol Interaction Is Complicated
"These findings seemingly contradict a previous [Global Burden of Diseases, Injuries, and Risk Factors Study] estimate published in The Lancet, which emphasized that any alcohol use, regardless of amount, leads to health loss across populations," wrote Robyn Burton, PhD, and Nick Sheron, MD, both of King's College, London, in an accompanying comment.
However, the novel methods of weighting relative risk curves according to levels of underlying disease drive the difference in results, along with disaggregated estimates by age, sex, and region, they said.
"Across most geographical regions in this latest analysis, injuries accounted for most alcohol-related harm in younger age groups. This led to a minimum risk level of zero, or very close to zero, among individuals aged 15-39 years across all geographical regions," which is lower than the level for older adults because of the shift in alcohol-related disease burden towards cardiovascular disease and cancers, they said. "This highlights the need to consider existing rates of disease in a population when trying to determine the total harm posed by alcohol," the commentators wrote.
In an additional commentary, Tony Rao, MD, a visiting clinical research fellow in psychiatry at King's College, London, noted that "the elephant in the room with this study is the interpretation of risk based on outcomes for cardiovascular disease – particularly in older people. We know that any purported health benefits from alcohol on the heart and circulation are balanced out by the increased risk from other conditions such as cancer, liver disease, and mental disorders such as depression and dementia," Rao said. "If we are to simply draw the conclusion that older people should continue or start drinking small amounts because it protects against diseases affecting heart and circulation – which still remains controversial – other lifestyle changes or the use of drugs targeted at individual cardiovascular disorders seem like a less harmful way of improving health and wellbeing."
Data Can Guide Clinical Practice
No previous study has examined the effect of the theoretical minimum risk of alcohol consumption by geography, age, sex, and time in the context of background disease rates, said Noel Deep, MD, in an interview.
"This study enabled the researchers to quantify the proportion of the population that consumed alcohol in amounts that exceeded the thresholds by location, age, sex, and year, and this can serve as a guide in our efforts to target the control of alcohol intake by individuals," said Deep, a general internist in private practice in Antigo, Wisc. He also serves as chief medical officer and a staff physician at Aspirus Langlade Hospital in Antigo.
The first take-home message for clinicians is that even low levels of alcohol consumption can have deleterious effects on the health of patients, and patients should be advised accordingly based on the prevalence of diseases in that community and geographic area, Deep said. "Secondly, clinicians should also consider the risk of alcohol consumption on all forms of health impacts in a given population rather than just focusing on alcohol-related health conditions," he added.
"This study provides us with the data to tailor our efforts in educating the clinicians and the public about the relationship between alcohol consumption and disease outcomes based on the observed disease rates in each population," Deep explained. "The data should provide another reason for physicians to advise their younger patients, especially the younger males, to avoid or minimize alcohol use," he said. The data also can help clinicians formulate public health messaging and community education to reduce harmful alcohol use, he added.
As for additional research, Deep said he would like to see data on the difference in the health-related effects of alcohol in binge-drinkers vs. those who regularly consume alcohol on a daily basis. "It would probably also be helpful to figure out what type of alcohol is being studied and the quality of the alcohol," he said.
The study was supported by the Bill and Melinda Gates Foundation. Bryazka and colleagues had no financial conflicts to disclose. Burton disclosed serving as a consultant to the World Health Organization European Office for the Prevention and Control of Noncommunicable Diseases. Sheron had no financial conflicts to disclose. Deep had no financial conflicts to disclose, but serves on the Editorial Advisory Board of Internal Medicine News.
The study was supported by the Bill and Melinda Gates Foundation.
This article originally appeared on MDedge.com, part of the Medscape Professional Network.
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Cite this: Moderate Drinking Shows More Benefit for Older vs Younger Adults - Medscape - Jul 20, 2022.