Abstract 13966: High Cardiorespiratory Fitness Attenuates Carotid Intima Media Thickening In Men With Metabolic Syndrome
Introduction: High levels of cardiorespiratory fitness (fitness) provide a strong protective effect against CVD mortality in men with the metabolic syndrome (MetS), but the underlying mechanisms are not fully understood. Carotid intima media thickness has been associated with increased risk of CVD and is increased with metabolic syndrome. We evaluated whether high fitness attenuates carotid intima media thickness in 8104 men (mean age 51 ± 7 yrs) who participated in a medical screening program.
Methods: We measured common carotid artery intima media thickness (CIMT) using B-mode ultrasound. Fitness was directly measured by peak oxygen uptake using expired gas analysis during maximal treadmill testing and was classified as low fit (<20%), moderate fit (20–60%), and high fit (> or =60%) categories based on age-specific peak oxygen uptake percentiles.
Results: The prevalence of the MetS defined by NCEP criteria was 8.4% (n=684). Men with MetS had significantly higher mean CIMT than men without MetS (0.94±0.2 vs. 0.89±0.2mm, p<0.01). CIMT is increased with increasing number of risk factors for MetS (p<0.01). Men in the high fit group had significantly lower mean CIMT than men in the low fit group without MetS (0.95±0.2 vs. 0.88±0.2mm, p<0.01) and with MetS (1.02±0.2 vs. 0.92±0.2mm, p<0.01). Fitness was inversely correlated with CIMT in men with (p=−0.26, p<0.01) and without MetS (p=−0.25, p<0.01). In multivariable regression models that adjusted for age, BMI, waist girth, smoking, SBP, TC/HDL-C ratio, glucose and CRP, fitness was inversely associated with CIMT (β=−0.10, p<0.01). Interestingly, men in the high fit group with MetS had significantly lower mean CIMT than men in the low fit group without MetS (0.86±0.2mm vs. 0.97±0.2 mm, p<0.05).
Conclusion: These results demonstrate that high cardiorespiratory fitness is inversely associated with CIMT in men with and without MetS and increased CIMT in the metabolic syndrome is attenuated by high cardiorespiratory fitness.
- © 2010 by American Heart Association, Inc.