Abstract 16195: Inverse Relationship Between Inflammation and Cardiorespiratory Fitness: The Henry Ford Hospital ExercIse Testing Project (FIT Project)

Abstract

Introduction: High sensitivity-C reactive protein (hs-CRP) is a measure of the degree of inflammation and has been associated with risk of coronary artery disease. Hypothesis: Hs-CRP is independently inversely associated with cardiorespiratory fitness (CRF). Methods: This is a cross sectional study of patients without heart failure or known coronary artery disease underwent graded exercise stress test in Henry Ford Health System (Detroit) according to Bruce protocol and CRF was estimated as peak metabolic equivalents (METs). Hs-CRP was dichotomized by 75th percentile and the relationship between CRF and hs-CRP was assessed by unadjusted and adjusted logistic regression model for age, sex, race, hypertension, diabetes, hyperlipidemia, smoking, total cholesterol, HDL, aspirin use, statin use and obesity. Results: A total of 4381 patients (mean age 54±11 years, 58% male, 79% whites) were analyzed. The 75th percentile of hs-CRP was 4.2 mg/L. Mean hs-CRP was higher in women, blacks, hypertensives, diabetics, smokers, and obese patients. In unadjusted analysis, CRF was inversely associated with highest quartile of hs-CRP (OR per 1 MET increase in CRF 0.82; 95% CI 0.81 - 0.84, p <0.0001). In multiple logistic regression model, CRF remained inversely associated with hs-CRP (OR per 1 MET increase in CRF 0.83; 95% CI 0.80 - 0.86, p 12 METS) compared to individuals with poor exercise capacity (<6 METS) had a 47% lower risk of having highest quartile of hs-CRP (OR 0.53; 95% CI 0.46 - 0.62, p <0.0001). Mean hs-CRP level decreased with increasing category of CRF (figure). There was a negative linear relationship between log transformed hs-CRP and peak METs achieved (r = -0.32, p<0.0001). Conclusions: In conclusion, exercise capacity, as measured by estimated Mets, was associated with reduced inflammation as measured by hs-CRP. The underlying pathophysiology between hs-CRP and CRF warrants further investigation.