Habitual physical activity is associated with endothelial function and endothelial progenitor cells in patients with stable coronary artery disease

BackgroundExercise training reduces mortality in patients with coronary artery disease (CAD); however, the impact of habitual physical activity level (PAL) on vascular endothelial function and circulating endothelial progenitor cells (EPCs) remain unknown.MethodsWe assessed habitual PAL using a validated International Physical Activity Questionnaire in 116 patients (67.8 ± 9.5 years; 81% male) with stable CAD and preserved left ventricular ejection fraction ≥ 45%. The number of circulating CD34/KDR+ and CD133/KDR+ EPCs was determined by flow cytometry, and brachial artery flow-mediated dilation (FMD) was measured.ResultsThe mean PAL of CAD patients with 1644 MET min/week (where MET is metabolic equivalents). With higher habitual PAL tertiles, there were significant linear trends of increased FMD (P = 0.001) and CD133/KDR+ EPCs (P = 0.03), but not of CD34/KDR+ EPCs. Patients with the highest tertile of PAL were associated with an absolute increase of 1.89% in FMD (relative increase 68%, P = 0.003) and 0.12...