High aerobic fitness associated with less advanced coronary atherosclerosis
MedWire News: Middle-aged men with high aerobic fitness are less likely to have advanced coronary atherosclerosis than their less-fit peers, research suggests.
The findings arise from an analysis of 8565 asymptomatic men who underwent both exercise testing and coronary calcium scoring between December 2002 and December 2010.
Participants were grouped into five age categories: under 50, 50-54, 55-59, 60-64, and 65 years or older. Coronary calcification was assessed using the Agatston score, and those with coronary artery calcium (CAC) above the 75th percentile for each age group were defined as having advanced CAC. A treadmill exercise test was performed using the modified Bruce protocol to evaluate participants' maximal oxygen uptake (VO2 max).
As reported in the American Journal of Cardiology, the average VO2 max was 32 mL/kg per minute, and 34% of participants had a positive CAC score.
Risk factors such as age, blood pressure, total cholesterol, triglycerides, low-density lipoprotein cholesterol, body mass index (BMI), fasting glucose, and 10-year absolute risk for coronary events were positively correlated with the CAC score.
By contrast, the VO2 max showed an inverse correlation with the CAC score. Indeed, the proportion of men with advanced CAC in the lowest quartile of the VO2 max was 1.7 times greater than in the highest quartile (28.6 vs 16.5%).
Multiple logistic regression analysis revealed that those in the highest VO2 max quartile were 40% less likely to have advanced CAC than those in the lowest quartile after adjustment for age, hypertension, hemoglobin A1c, current smoking, BMI, and habitual exercise frequency.
Of note, "as a cross-sectional analysis, the present study cannot infer the cause and effect relation," say Jidong Sung and team from Sungkyunkwan University School of Medicine in Seoul, Korea.
However, they suggest that the degree of subclinical coronary artery disease "might be one of the mechanisms connecting aerobic fitness and cardiovascular outcome."
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By Nikki Withers