Exercise mediates alcohol brain harm
medwireNews: Researchers have found that aerobic exercise may mitigate the damaging effect of heavy alcohol consumption on white matter in the brain.
"We found that for people who drink a lot and exercise a lot, there was not a strong link between alcohol and white matter," said study author Hollis Karoly (University of Colorado, Boulder, USA) in a press statement.
"But for people who drink a lot and don't exercise, our study showed the integrity of white matter is compromised in several areas of the brain."
The study included data on 60 participants aged 21-55 years old whose alcohol consumption in the prior 60 days ranged from 0 to 303 drinks (mean: 101.2) and aerobic exercise participation ranged from 0 to 420 minutes in the prior 3 months (mean: 96.0).
The authors examined the white matter in five tracts that have previously been associated with alcohol consumption - the external capsule, superior longitudinal fasciculus, anterior corona radiata, superior corona radiate, and fornix - according to fractional anisotropy and examined their interaction with exercise (as measured by the Voluntary Aerobic Exercise Questionnaire) and the number of drinks consumed within the previous 60 days.
In regression analyses, there was a significant effect of exercise by alcohol consumption interaction in relation to the external capsule and the superior longitudinal fasciculus, the authors report in Alcoholism: Clinical and Experimental Research.
However, further analysis showed that a relationship between alcohol consumption and reduced fractional anisotropy in these areas was only observed in those who had below average levels of exercise.
Importantly, the findings were unaffected when the authors accounted for smoking and cannabis use, suggesting that these factors did not mediate the association.
Karoly and colleagues also note that the association between consumption and loss of control over drinking (as measured by the Impaired Control Scale failed control subscale) was greater in individuals who exercised less compared with those who exercised more. The authors suggest this could indicate that exercise helps people to control their drinking, but that further research will be needed to clarify this.
Cardiovascular fitness has previously been associated with improved white matter integrity in aging populations, the early stages of Alzheimer's disease and in people with multiple sclerosis.
The authors say that their study is exploratory and further research will be needed to understand how much exercise is needed to achieve neural benefits among heavy alcohol consumers, as well as over what duration.
Nevertheless, they believe that the findings provide a valuable starting point to explore the relationship between alcohol, exercise and the brain.
"Certainly clinicians could use these findings to support prescribing aerobic exercise programs as an adjunct treatment for individuals dealing with psychological or physiological problems related to a heavy alcohol-use history," Karoly concludes.
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2013
By Kirsty Oswald, medwireNews Reporter