title: Endothelial dysfunction correlates with exaggerated exercise pressor response during whole body maximal exercise in chronic kidney disease.
abstract: Chronic kidney disease (CKD) patients have exercise intolerance associated with increased cardiovascular mortality. Previous studies demonstrate that blood pressure (BP) and sympathetic nerve responses to handgrip exercise are exaggerated in CKD. These patients also have decreased nitric oxide (NO) bioavailability and endothelial dysfunction, which could potentially lead to an impaired ability to vasodilate during exercise. We hypothesized that CKD patients have exaggerated BP responses during maximal whole body exercise and that endothelial dysfunction correlates with greater exercise pressor responses in these patients. Brachial artery flow-mediated dilation (FMD) was assessed before maximal treadmill exercise in 56 participants: 38 CKD (56.7 ± 1.2 yr old, 38 men) and 21 controls (52.8 ± 1.8 yr old, 20 men). During maximal treadmill exercise, the slope-of-rise in systolic BP (+10.32 vs. +7.75 mmHg/stage,P< 0.001), mean arterial pressure (+3.50 vs. +2.63 mmHg/stage,P= 0.004), and heart rate (+11.87 vs. +10.69 beats·min-1·stage-1,P= 0.031) was significantly greater in CKD compared with controls. Baseline FMD was significantly lower in CKD (2.76 ± 0.42% vs. 5.84 ± 0.97%,P= 0.008). Lower FMD values were significantly associated with a higher slope-of-rise in systolic BP (+11.05 vs. 8.71 mmHg/stage,P= 0.003) during exercise in CKD, as well as poorer exercise capacity measured as peak oxygen uptake (V̇o2peak; 19.47 ± 1.47 vs. 24.57 ± 1.51 ml·min-1·kg-1,P< 0.001). These findings demonstrate that low FMD in CKD correlates with augmented BP responses during exercise and lower V̇o2peak, suggesting that endothelial dysfunction may contribute to exaggerated exercise pressor responses and poor exercise capacity in CKD patients.
authors.affiliation: Division of Renal Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia.|Research Service Line, Department of Veterans Affairs Medical Center, Decatur, Georgia.
authors.forename: Ryan M
authors.identifier: 0000-0003-4144-1155
authors.initials: RM
authors.lastname: Downey
authors.affiliation: Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, Georgia.
authors.forename: Peizhou
authors.initials: P
authors.lastname: Liao
authors.affiliation: Clinical Research Network, Atlanta Clinical and Translational Science Institute, Emory University School of Medicine, Atlanta, Georgia; and.
authors.forename: Erin C
authors.initials: EC
authors.lastname: Millson
authors.affiliation: Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia.
authors.forename: Arshed A
authors.initials: AA
authors.lastname: Quyyumi
authors.affiliation: Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia.
authors.forename: Salman
authors.initials: S
authors.lastname: Sher
authors.affiliation: Division of Renal Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia; jeanie.park@emory.edu.|Research Service Line, Department of Veterans Affairs Medical Center, Decatur, Georgia.
authors.forename: Jeanie
authors.initials: J
authors.lastname: Park
mesh_terms: D062186:Arterial Pressure; D001916:Brachial Artery / Q000378:metabolism / Q000503:physiopathology*; D002318:Cardiovascular Diseases / Q000209:etiology / Q000503:physiopathology; D016022:Case-Control Studies; D004730:Endothelium, Vascular / Q000378:metabolism / Q000503:physiopathology*; D015444:Exercise; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D006304:Health Status; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism; D010101:Oxygen Consumption; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000175:diagnosis / Q000378:metabolism / Q000503:physiopathology*; D013997:Time Factors; D014664:Vasodilation; D016138:Walking
chemical_list: D009569:Nitric Oxide
keywords: chronic kidney disease; endothelial dysfunction; exercise; exercise pressor reflex; flow-mediated dilation