Good cardiorespiratory fitness decreases risk for nonfatal MI, HF in men
Cardiorespiratory fitness was inversely associated with acute nonfatal MI and HF risk in a cohort of men, according to new findings.
“[CV] fitness is an important and modifiable risk factor associated with mortality,” Hassan Khan, MD, PhD, of Emory University, and colleagues wrote. “Multiple studies have demonstrated a consistent, inverse association between cardiorespiratory fitness and mortality even after adjustment for traditional risk factors. However, whether these associations persist in relation to nonfatal [CV] events has not been evaluated before.”
Khan and colleagues measured cardiorespiratory fitness in Finnish men (n = 2,089; aged 42 to 61 years) using a respiratory gas exchange analyzer to assess maximal oxygen uptake.
During follow-up (mean, 19.1 years), 522 nonfatal acute MI events, 198 acute all-cause nonfatal stroke events and 221 nonfatal HF events were recorded.
After adjustments for CV risk factors, a 1-metabolic equivalent increase in cardiorespiratory fitness was associated with a decreased risk for nonfatal MI (HR = 0.93; 95% CI, 0.88-0.97) nonfatal stroke (HR = 0.94; 95% CI, 0.87-1.01) and nonfatal HF event (HR = 0.84; 95% CI, 0.78-0.91).
When cardiorespiratory fitness was added to a conventional CVD risk score, there was significant improvement in discrimination for both nonfatal MI (change in C index = 0.015; 95% CI, 0.01-0.02) and HF (change in C index = 0.04; 95% CI, 0.01-0.06) and in reclassification for nonfatal MI (change in category free net reclassification index = 0.27; 95% CI, 0.13-0.42; P < .01) and for nonfatal HF (change in category free net reclassification index = 0.88; 95% CI, 0.53-1.24; P < .01)).
“Although the causal nature of these associations remains to be investigated, it is likely that higher levels of [cardiorespiratory fitness] improve [CV] risk profile, thereby decreasing the risk of future CVD events,” the researchers wrote. “Several physiological and metabolic mechanism underpin the association of low [cardiorespiratory fitness] with increased risk of CVD. Lower levels of physical activity are associated with endothelial dysfunction which contributes to preclinical atherosclerosis. Physical inactivity with poor [cardiorespiratory fitness] leads to elevated levels of [BP] and serum lipids, insulin resistance and obesity, all of which predispose to the development of CVD.” – by Cassie Homer
Disclosure: The researchers report no relevant financial disclosures.