Low Cardiorespiratory Fitness Is Associated with Elevated C-Reactive Protein Levels in Women with Type 2 Diabetes

Abstract

OBJECTIVE - The purpose of this study was to examine differences in novel markers of cardiovascular disease (CVD) in women with type 2 diabetes stratified according to cardiorespiratory fitness. RESEARCH DESIGN AND METHODS - A total of 28 women (mean age 57 ± 6 years) with type 2 diabetes who were free from overt CVD were placed into low cardiorespiratory fitness (LCF) or average cardiorespiratory fitness (ACF) groups based on a graded exercise test to exhaustion. A group of eight women without type 2 diabetes were also examined and served as healthy control subjects. The median VO2peak value was used as a cutoff for group determination. We assessed both conventional CVD risk factors, including blood pressure, BMI, and lipid profile, as well as novel CVD risk factors, such as left ventricular filling dynamics, arterial stiffness, fasting insulin, and C-reactive protein (CRP). RESULTS - VO2peak values were 69 ± 14 and 91 ± 24% of predicted values for sedentary age-matched healthy individuals in the LCF and ACF groups, respectively. BMI was significantly greater in the LCF group (P < 0.05); however, no differences were observed in age, lipid profile, or resting hemodynamics. CRP was 3.3-fold higher in the LCF group (6.3 ± 41. vs. 1. 9 ± 1.7 mg/l, P < 0.05), whereas other novel markers of CVD were not significantly different between the groups. Significant negative relationships were observed between VO2peak and both CRP (r = -0.49) and the homeostasis model assessment index (r = -0.48) (P < 0.05). CONCLUSIONS - The novel finding of this investigation is that low cardiorespiratory fitness is associated with elevated CRP and reduced fasting glucose control in women with type 2 diabetes.