Alcohol and blood pressure
Authors: Manan Pareek, Michael Hecht Olsen
Journal: The Lancet Public Health (2017)

The systematic review and meta-analysis by Michael Roerecke and colleagues1Roerecke M Kaczorowski J Tobe ST Gmel G Hasan OS Rehm J The effect of a reduction in alcohol consumption on blood pressure; a systematic review and meta-analysis.Lancet Public Health. 2017; 2: 108-120Summary Full Text Full Text PDF Scopus (223) Google Scholar extends our knowledge of the association between alcohol and blood pressure by showing a dose-dependent association between baseline alcohol intake and the blood pressure-lowering effect of a subsequent reduction in alcohol intake, with an apparent threshold at two standard drinks—ie, 24 g pure alcohol per day. In other words, although no significant effect of lowering alcohol consumption was recorded in individuals with a daily intake of two or fewer drinks, effect sizes were greatest in those who had the highest intake beyond two drinks per day, irrespective of baseline cardiovascular risk. For example, in people who drank six or more drinks per day, a reduction in alcohol intake of about 50% was associated with mean reductions in systolic and diastolic blood pressure of 5·50 mm Hg and 3·97 mm Hg, respectively, similar to the benefit of other lifestyle changes—eg, increased physical activity and weight loss.2Mancia G Fagard R Narkiewicz K et al.2013 ESH/ESC guidelines for the management of arterial hypertension: the Task Force for the Management of Arterial Hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC).Eur Heart J. 2013; 34: 2159-2219Crossref PubMed Scopus (3739) Google Scholar Three closely linked key questions require further clarification: the mechanisms for the observed association; strategies for ensuring a sustained reduction in alcohol consumption and subsequently in blood pressure as median trial duration was limited to 4 weeks; and the prognostic implications of blood pressure-lowering due to reduced alcohol consumption. In this regard, an inherent weakness of the study was the paucity of information about potentially related behavioural and lifestyle changes, including treatment compliance, stress coping, physical activity, diet, and weight.3Forouzanfar MH Alexander L et al.GBD 2013 Risk Factors CollaboratorsGlobal, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks in 188 countries, 1990–2013: a systematic analysis for the Global Burden of Disease Study 2013.Lancet. 2015; 386: 2287-2323Summary Full Text Full Text PDF PubMed Scopus (1918) Google Scholar This is especially important because individuals capable of reducing their alcohol intake from 6–10 to 3–5 drinks per day might represent a highly motivated group, who are willing to adopt additional healthy lifestyle changes. Furthermore, this mechanistic uncertainty obscures prognostication with respect to cardiovascular outcome. However, because several components of lifestyle modification have proven advantageous without adverse effects,4Appel LJ Champagne CM Harsha DW et al.Effects of comprehensive lifestyle modification on blood pressure control: main results of the PREMIER clinical trial.JAMA. 2003; 289: 2083-2093Crossref PubMed Scopus (1172) Google Scholar, 5Elmer PJ Obarzanek E Vollmer WM et al.Effects of comprehensive lifestyle modification on diet, weight, physical fitness, and blood pressure control: 18-month results of a randomized trial.Ann Intern Med. 2006; 144: 485-495Crossref PubMed Scopus (463) Google Scholar it is likely that a sustained reduction in alcohol consumption in people drinking more than two drinks per day will be accompanied by a reduction in both blood pressure and subsequent cardiovascular events. Recent findings have brought into question the previous idea of a protective benefit of low-moderate alcohol intake (ie, 1–2 drinks per day).6Holmes MV Dale CE Zuccolo L et al.Association between alcohol and cardiovascular disease: Mendelian randomisation analysis based on individual participant data.BMJ. 2014; 349: g4164Crossref PubMed Scopus (462) Google Scholar, 7Knott CS Coombs N Stamatakis E Biddulph JP All cause mortality and the case for age specific alcohol consumption guidelines: pooled analyses of up to 10 population based cohorts.BMJ. 2015; 350: h384Crossref PubMed Scopus (147) Google Scholar Whereas consumption of more than two drinks per day is associated with adverse outcomes, it remains unclear whether one to two drinks per day have protective, neutral, or harmful effects. Therefore, contemporary guidelines for both hypertension2Mancia G Fagard R Narkiewicz K et al.2013 ESH/ESC guidelines for the management of arterial hypertension: the Task Force for the Management of Arterial Hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC).Eur Heart J. 2013; 34: 2159-2219Crossref PubMed Scopus (3739) Google Scholar and cardiovascular disease prevention8Piepoli MF Hoes AW Agewall S et al.2016 European Guidelines on cardiovascular disease prevention in clinical practice: The Sixth Joint Task Force of the European Society of Cardiology and Other Societies on Cardiovascular Disease Prevention in Clinical Practice (constituted by representatives of 10 societies and by invited experts): Developed with the special contribution of the European Association for Cardiovascular Prevention & Rehabilitation (EACPR).Eur Heart J. 2016; 37: 315-381Crossref Scopus (4578) Google Scholar recommend moderation of alcohol consumption, corresponding to approximate daily intakes of less than 20 g in men and less than 10 g in women. Although the results presented agree with the recommendations for men, data for women were scarce and should be interpreted cautiously. For this reason, it seems reasonable to continue with the current sex-specific recommendations until further evidence is available. Roerecke and colleagues should be commended for their important study, which shows that a reduction in alcohol consumption in people with a baseline intake of more than two drinks per day is associated with a significant blood pressure reduction that increases with higher baseline alcohol intake. This finding is of great public health interest because both alcohol intake and raised blood pressure are important risk factors for the global burden of non-communicable diseases3Forouzanfar MH Alexander L et al.GBD 2013 Risk Factors CollaboratorsGlobal, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks in 188 countries, 1990–2013: a systematic analysis for the Global Burden of Disease Study 2013.Lancet. 2015; 386: 2287-2323Summary Full Text Full Text PDF PubMed Scopus (1918) Google Scholar and, therefore, are targets for the WHO global action plan for the prevention and control of non-communicable diseases9WHOGlobal Action Plan for the Prevention and Control of Noncommunicable Diseases 2013–2020.http://www.who.int/nmh/events/ncd_action_plan/en/Date: 2013Google Scholar and the collaborative HEARTS10WHOHEARTS. Technical Package for Cardiovascular Disease Management in Primary Health Care.http://www.who.int/cardiovascular_diseases/hearts/en/Date: 2016Google Scholar initiative addressing healthy lifestyle, evidence-based protocols, access to essential medicines and technologies, risk-based management, team-based care and training, systems for monitoring and implementation module. Soon, HEARTS might help to answer the unanswered mechanistic questions through a combination of intervention and monitoring. MHO reports personal fees from Boehringer and Ingelheim and Astra Zeneca, and grants from Novo Nordic Foundation. MP declares no competing interests. The effect of a reduction in alcohol consumption on blood pressure: a systematic review and meta-analysisReducing alcohol intake lowers blood pressure in a dose-dependent manner with an apparent threshold effect. Implementation of effective alcohol interventions in people who drink more than two drinks per day would reduce the disease burden from both alcohol consumption and hypertension, and should be prioritised in countries with substantial alcohol-attributable risk. Full-Text PDF Open Access