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CardioSource WorldNews | A Shot of Reality: Questions About the Health Benefits of ‘Moderate’ Alcohol Use
If you still believe alcohol has health benefits, then cheers! If you are part of a growing number of skeptics who just don’t buy the data, would you prefer still or sparkling water? As one recent paper asked: Has the leaning tower of presumed health benefits from ‘moderate’ alcohol use finally collapsed?1
It might be surprising news considering all the positive press in recent years given to the beneficial effects of moderate alcohol consumption. This was based on about 100 (some say 200) observational studies and, as Mariann R. Piano, PhD, RN, noted recently, there is indeed a relationship between cardiovascular disease mortality and the average amount of alcohol consumed per day that is consistent with a J-shaped curve. A similar relationship has been reported for ischemic heart disease (IHD) mortality in one meta-analysis.2 Compared to long-term abstinence, daily consumption of small or moderate amounts of alcohol was associated with reduced mortality from IHD with the nadir of the relative risk curve at about 30 g ethanol per day for men and a substantially lower amount for women (about 11 g/day for IHD mortality and 14 g/day for IHD morbidity).2 At higher daily intakes of alcohol, the risk reduction was gradually replaced by increased risk.
Dr. Piano is a professor and department head in the School of Nursing, University of Illinois, Chicago. So, what’s driving the move away from the supposed healthful effects of moderate alcohol consumption? “We have data from new methodologies, such as Mendelian randomization and data from large international meta-analysis studies that have led us to rethink this J-shaped relationship such that the dose-response has shifted to the left.”
For example, in one such Mendelian analysis of 261,991 individuals of European descent, reduction of alcohol consumption, even for light to moderate drinkers, is beneficial for cardiovascular health.3
Also, Dr. Piano pointed to a large number of individual variables that can influence response to alcohol, including genetics, sex, race/ethnicity, and socioeconomic status.4
Have You Heard the Good News?
Another reason you may still think moderate alcohol consumption is the subject of considerable debate is the fact that bad news on the topic just doesn’t seem as likely to hit the headlines. There is certainly a large audience for “good news” about alcohol consumption. Any possibility of benefit is welcome news to those who enjoy its consumption and to those who profit from its sale.
Yet, in recent years, there has been growing concern regarding whether purported beneficial effects of moderate alcohol use are real or just due to confounding factors not adjusted for in the studies performed.1
Also, new data have upended or at least “moved the J curve” to the left. In men and women, alcohol consumption exceeding ~1 to 2 drinks/day is associated with an increase in the relative risk of hypertension and, as Dr. Piano pointed out, binge drinking on a regular basis is likely to ‘acutely’ increase blood pressure and the risk of stroke. Binge drinking, defined as 6 or more drinks in a single episode of drinking, significantly increases the risk of myocardial infarction (MI) over the next 24 hours (odds ratio: 1.4; p < 0.01 compared to less consumption of alcohol).5
Indeed, in an analysis of data from 52 countries, the protective association between alcohol use and MI was no longer significant when any alcohol was consumed more than 4 times a week.5 So much for the protective effects of a drink a day. In data from the INTERHEART study, “alcohol use” with a frequency of 1 to 4 times a week (again, not a day – a week) was associated with a reduced risk of MI; anything more than that had a deleterious effect on risk of myocardial infarction.
Importantly, INTERHEART investigators noted that the protective effect was not uniform among all regions/populations. Where there seemed to be a protective effect in Europe, North America, and Australia/New Zealand, there was none at all seen for people in Southeast Asia. Also, the protective association of alcohol against MI was greater in women and in individuals ≥ 45 years of age.
Stroke is also an important consideration: evidence suggests that the level of alcohol consumption reported to be protective for the heart is lost for the brain in terms of incident stroke and stroke mortality.5 In other words, levels of consumption that seem protective for the heart actually increases risk of stroke.
Dr. Piano recently wrote a review on alcohol’s effects on the cardiovascular system6 and has specifically written about alcoholic cardiomyopathy,7 which is found in individuals with a history of long-term heavy alcohol consumption. This type of cardiomyopathy is associated with a number of adverse histological, cellular, and structural changes within the myocardium and several mechanisms are implicated in mediating the adverse effects of ethanol, including the generation of oxidative stress, apoptotic cell death, impaired mitochondrial bioenergetics/stress, derangements in fatty acid metabolism and transport, and accelerated protein catabolism.
As this issue of ACCEL was being finalized, a study led by researchers from Loyola Medicine and Loyola University Chicago reported a potential new health concern related to excessive alcohol consumption.8 They found that adults who drink excessively have less nitric oxide in their exhaled breath than adults who don’t drink. The finding, published in Chest, is significant because nitric oxide helps protect against certain harmful bacteria.
“Alcohol appears to disrupt the healthy balance in the lung,” said lead author Majid Afshar, MD. This is the first study to report such a link between excessive alcohol consumption and nitric oxide.
If you are looking for some clinical advice, here is what Dr. Piano says you should know about low-risk drinking:
- A low-to-moderate level of alcohol consumption (1 to 2 drinks/day, but not every day) is probably not harmful to overall cardiovascular health.
- In the absence of randomized controlled clinical trials, health care professionals should not recommend alcohol consumption as a primary or secondary lifestyle intervention, but rather should continue to recommend established strategies, such as a healthy diet and physical activity.
- The U.S. National Institute on Alcohol Abuse and Alcoholism recommends no more than 14 drinks per week for men and no more than 7 drinks per week for females. To minimize any risk of dependence, there should be at least 1 day/week when no alcohol is consumed.
- Lower levels may be appropriate for specific groups – such as the elderly or those of different racial groups (e.g., South Asia and Middle East, African Americans).
- Those who currently abstain from alcohol should not begin drinking to reduce their risk of health problems.
- In certain circumstances and for certain individuals the use of alcoholic beverages is contraindicated (e.g., certain psychological conditions, medications).
- High levels of alcohol consumption (defined as >4 or 5 drinks/day) or “binge drinking” are harmful to many aspects of health and well-being.
- Chikritzhs T, Stockwell T, Naimi T, Andreasson S, Dangardt F, Liang W. Addiction. 2015;110:726-7.
- Roerecke M, Rehm J. Addiction. 2012;107:1246-60.
- Holmes MV, Dale CE, Zuccolo L, et al. BMJ. 2014;349:g4164.
- Ronksley PE, Brien SE, Turner BJ, Mukamal KJ, Ghali WA. BMJ. 2011;342:d671.
- Leong DP, Smyth A, Teo KK, et al. Circulation. 2014;130:390-8.
- Piano MR. Alcohol’s Effects on the Cardiovascular System. Alcohol Research Current Reviews. Alcohol Res Health. In press, 2016.
- Piano MR, Phillips SA. Cardiovasc Toxicol. 2014; 14:291-308.
- Afshar M, Poole JA, Cao G, et al. Chest. 2016;150: 196-209.
Revolution in Device Innovation
The implantable defibrillator of the future
We are going to witness a revolution in medical device innovation, a transformation that will largely change medical devices as we know them today.” That’s the primary thesis of Paul J. Wang, MD, FACC, a professor and director of the Stanford Arrhythmia Service at Stanford University School of Medicine. He was a co-inventor of catheter cryoablation and he founded the annual Stanford Biodesign New Arrhythmia Technologies Retreat, focusing on new technological advances in arrhythmia management and diagnosis.
Sudden cardiac arrest (SCA) is clearly a public health issue. It is a significant killer, with about a 95% fatality rate without implantable cardioverter-defibrillator (ICD) protection. ICDs have a Class I indication for most patients at high-risk of SCA (guidelines clearly outline these at-risk groups1-4) and studies show that ICDs are cost effective. About 1 in 8 patients who receives such a device will survive thanks to the proper discharge of their ICD.
Up ahead, Dr. Wang foresees transformative technology; historically speaking, he’s not talking a small leap to “a better horse-drawn carriage” but rather a much bigger technological leap: think “car.” When cars first came on the scene they had definite advantages over a horse and buggy. While those early vehicles showed some similarities to what’s on the road today, it was really only in the basics: 4 wheels, a ‘box,’ a driver, an engine, and a power source. What’s needed to advance ICD technology is to learn from the auto industry, which concentrated on size, weight, form (smaller, lighter, yet stronger), lower cost, greater reliability, greater comfort (consumer acceptance, more comfortable), and novel energy sources. Ahead: smart cars, driverless cars, analytics based on constant data sensing and gathering, and automobiles fully networked to enhance safety.
Using the same approach, investigators are developing new unbreakable leads (conductor and insulation) for cardiac pacing.
In the case of preventing SCA, think one recent step forward: the subcutaneous ICD. Similarly, efforts are driving new generators that are extremely reliable (no faults) with redundant components and modes. When things do go wrong, then improved testing will make it easier to identify component faults and ease repair.
Energy sources are changing, too: look for mechanical motion electrical generators that recharge with activity; new-generation batteries that exceed the life of most patients; and rechargeable batteries.
You can set your TV and home security from any distance: why not an ICD that can be monitored anytime and anywhere; be reprogrammed/updated with new software; and – here’s a critical feature – be completely secure.
Storage is now limitless, thanks to “the cloud,” so new devices will permit unlimited event storage – it moves to the cloud automatically – and the device will function as a Holter/on-demand monitor.
The Future is Now
Already, Dr. Wang points out, when a 24-hour Holter isn’t sufficient but an implanted device isn’t warranted, there is already a stick-on heart monitor called the Zio Patch made by digital health care company iRhythm. Their “wearable sensors” record a patient’s rhythm for 14 days. Then the device is returned to the company, the data are analyzed via proprietary algorithms, and the clinician is sent a focused report.
With their purchase of Corventis, Medtronic now has a mobile cardiac telemetry system that uses a peel-and-stick patch. InfoBionic (Lowell, Massachusetts) is set to commercialize its remote patient monitoring system, the MoMe Kardia, which is designed to help detect cardiac arrhythmias in patients by sensing electrical acitivity, respiration, and motion. The device can be worn as a necklace or belt attachment and transmits data to a cloud-based platform where the data are analyzed then sent on to the physician. The device works as a Holter, event, and mobile cardiac telemetry monitor. If a physician feels that the patient’s cardiac symptoms call for a different type of monitoring technology, they can switch the device remotely to any 1 of 3 main monitoring modes. A physician can access the patient’s MoMe Kardia data via web or iPad app.
Engineers recently figured out how to mass produce an inexpensive wearable patch that continuously monitors vital signs for health and performance tracking. (In case Advanced Materials is not on your reading list, see reference 5.) The investigators believe the tattoo-like device has the potential to outperform more traditional tools like cardiac monitors.
Prolonged cardiac monitoring may have tremendous research potential. The vast amounts of data collected and stored by these devices offer researchers a potential gold mine of data into when, how, and why people get into trouble and have an event.
The recently approved subcutaneous implantable cardioverter-defibrillator (S-ICD) offers the advantage of no need for intravenous and intracardiac leads and their associated risks and shortcomings. This is important because lead malfunction caused by conductor failure or insulation breach occurs in up to 40% of indwelling transvenous leads at 8 years after implantation. Failure occurs more commonly in active young patients or in patients with longer life expectancy who expose the leads to greater cumulative physical stress.
However, while a completely subcutaneous electrode configuration can treat potentially lethal ventricular tachyarrhythmia, its major disadvantage is its inability to provide bradycardia rate support and antitachycardia pacing to terminate ventricular tachycardia.
Another step forward was published in early 2016 when Fleur V.Y. Tjong, MD, from the Academic Medical Center in Amsterdam, and colleagues reported the first proof-of-concept preclinical study of a combined implant offering anti-tachycardia pacing via a leadless cardiac pacemaker combined with an S-ICD.6
Driving the future will be more efforts like Stanford’s Biodesign, recently renamed the Byers Center for Biodesign. It is involved in the whole process of innovating biodesign and accelerating research, recently expanding its focus to helping create technologies that can assist in addressing the affordability crisis in health care.
Looking ahead, Dr. Wang said, there will be more such programs. There will also be more support networks for cardiovascular medical device innovation, more incubators, more programs that train people in cardiovascular medical device innovation, and more meetings centered on innovation. Their real ‘product’ at Stanford, said Dr. Wang, is the hundreds of innovators who continue to move through their innovation programs.
- 1. Tracy CM, Epstein AE, Darbar D, et al.
- J Am Coll Cardiol. 2013;61:e6-e75.
- Yancy CW, Jessup M, Bozkurt B, et al.
- J Am Coll Cardiol. 2013;62:e147-e239.
- 3. O’Gara PT, Kushner FG, Ascheim DD, et al.
- J Am Coll Cardiol. 2013;61:e78-e140.
- 4. Wann L, Curtis AB, January CT, et al. J Am Coll Cardiol. 2011;57:223-242.
- 5. Yang S, Chen YC, Nicolini L, et al. Adv Mater. 2015;27:6423-30.
- 6. Tjong FY, Brouwer TF, Kooiman KM, et al.
- J Am Coll Cardiol. 2016;67:1865-6.
|Read the full October issue of CardioSource WorldNews at ACC.org/CSWN|
Keywords: CardioSource WorldNews, Alcohol Drinking, Alcoholic Beverages, Arrhythmias, Cardiac, Binge Drinking, Inventors, Life Style, Motor Activity, National Institute on Alcohol Abuse and Alcoholism (U.S.), Risk
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