Moderate Alcohol Consumption Increases Risk of Cognitive Decline

by | May 23, 2018 | 2017, Alcohol, Brain Health, Cognitive Health

Written by Angeline A. De Leon, Staff Writer. This study demonstrates that alcohol consumption, in a dose-dependent manner, was significantly associated with increased risk of brain hippocampal atrophy such that even moderate levels of alcohol consumption were harmful.

Historically, alcohol consumption, at moderate levels (defined as 72-144 g/weekly), has been viewed as innocuous 1. In fact, previous studies have even suggested that light-to-moderate drinking may offer a neuroprotective effect, with low-to-medium levels of alcohol consumption linked to lower risk of dementia, myocardial infarction, and stroke 2,3. However, recent neuroimging data have been unable to confirm the protective effects of moderate alcohol intake on brain health 4, and newer studies suggest that even light drinking may cause increased risk of certain types of cancer 5. While heavy drinking is known for its association with dementia and widespread brain atrophy 6, the impact of lower levels of alcohol consumption on neurocognitive health is still under investigation. Some studies, for example, show evidence of a relationship between moderate alcohol intake and increased white matter volume 7, but others report an inverse association with white matter integrity 8 or no association at all. In a 30-year longitudinal study 9 at the University of Oxford, investigators examined the effects of moderate alcohol consumption on structural measures of brain health and cognitive performance.

The prospective, observational cohort study involved a total of 550 community-dwelling participants (mean age = 43 years at baseline). At baseline and at regular five-year intervals, weekly alcohol intake was measured (“light drinking” defined as 1-6 units weekly, “moderate” as 7-13 units for women and 7-20 units for men), and cognitive function assessed using a series of neuropsychological tests which were administered a final time during the end-point brain scan. At the 30-year follow-up period, researchers performed a magnetic resonance imaging (MRI) scan and conducted a structural brain analysis looking at hippocampal atrophy, grey matter density, and white matter microstructure.

Compared with abstainers, higher alcohol consumption was found to be associated with increased risk of hippocampal atrophy in a dose-dependent manner such that although those consuming over 30 units weekly showed the highest risk (Odds Ratio = 5.8, 95% Confidence Interval: 1.8 to 18.6, p ≤ 0.001), even moderate levels of alcohol consumption (14-21 units weekly) showed increased odds of right-sided hippocampal atrophy (OR = 3.4, 95% CI: 1.4 to 8.1, p = 0.007). No protective effects were reported with light drinking over abstinence. Higher alcohol use predicted faster decline in lexical fluency (χ2 =14.4, p = 0.006) but not semantic fluency (χ2 =10.0, p = 0.04) or memory recall (χ2 =9.8, p = 0.04), and no significant association between alcohol consumption and cross-sectional performance on cognitive tests was detected.

Overall findings indicate that alcohol consumption, even in moderate quantities, is related to multiple markers of abnormal brain structure, including deterioration of the hippocampus, an organ critical for learning and memory. In agreement with more recent studies, evidence from the study shows the absence of any neuroprotective effects associated with light drinking. Instead, results support the recent revision of the UK government’s alcohol guidelines 10 and suggest the consideration of a similar reduction in the limits of alcohol intake currently recommended by US Federal Dietary guidelines. 

Source: Topiwala A, Allan CL, Valkanova V, et al. Moderate alcohol consumption as risk factor for adverse brain outcomes and cognitive decline: longitudinal cohort study. BMJ. 2017.357: j2353. DOI: 10.1136/bmj.j2353.

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.Posted May 23, 2018.

Angeline A. De Leon, MA, graduated from the University of Illinois at Urbana-Champaign in 2010, completing a bachelor’s degree in psychology, with a concentration in neuroscience. She received her master’s degree from The Ohio State University in 2013, where she studied clinical neuroscience within an integrative health program. Her specialized area of research involves the complementary use of neuroimaging and neuropsychology-based methodologies to examine how lifestyle factors, such as physical activity and meditation, can influence brain plasticity and enhance overall connectivity.

References:

  1. Stampfer MJ, Colditz GA, Willett WC, Speizer FE, Hennekens CH. A prospective study of moderate alcohol consumption and the risk of coronary disease and stroke in women. New England Journal of Medicine. 1988;319(5):267-273.
  2. Ruitenberg A, van Swieten JC, Witteman JC, et al. Alcohol consumption and risk of dementia: the Rotterdam Study. The Lancet. 2002;359(9303):281-286.
  3. Cleophas T. Wine, beer and spirits and the risk of myocardial infarction: a systematic review. Biomedicine & pharmacotherapy. 1999;53(9):417-423.
  4. Gu Y, Scarmeas N, Short EE, et al. Alcohol intake and brain structure in a multiethnic elderly cohort. Clinical Nutrition. 2014;33(4):662-667.
  5. Cao Y, Willett WC, Rimm EB, Stampfer MJ, Giovannucci EL. Light to moderate intake of alcohol, drinking patterns, and risk of cancer: results from two prospective US cohort studies. Bmj. 2015;351:h4238.
  6. Edition F. Diagnostic and statistical manual of mental disorders. Am Psychiatric Assoc; 2013.
  7. de Bruin EA, Pol HEH, Schnack HG, et al. Focal brain matter differences associated with lifetime alcohol intake and visual attention in male but not in female non-alcohol-dependent drinkers. Neuroimage. 2005;26(2):536-545.
  8. Anstey KJ, Mack HA, Cherbuin N. Alcohol consumption as a risk factor for dementia and cognitive decline: meta-analysis of prospective studies. The American journal of Geriatric psychiatry. 2009;17(7):542-555.
  9. Topiwala A, Allan CL, Valkanova V, et al. Moderate alcohol consumption as risk factor for adverse brain outcomes and cognitive decline: longitudinal cohort study. bmj. 2017;357:j2353.
  10. Health UDo, Services H. Dietary Guidelines for Americans 2015-2020. Skyhorse Publishing Inc.; 2017.