title: Association between physical performance and all-cause mortality in CKD.
abstract: In older adults, measurements of physical performance assess physical function and associate with mortality and disability. Muscle wasting and diminished physical performance often accompany CKD, resembling physiologic aging, but whether physical performance associates with clinical outcome in CKD is unknown. We evaluated 385 ambulatory, stroke-free participants with stage 2-4 CKD enrolled in clinic-based cohorts at the University of Washington and University of Maryland and Veterans Affairs Maryland Healthcare systems. We compared handgrip strength, usual gait speed, timed up and go (TUAG), and 6-minute walking distance with normative values and constructed Cox proportional hazards models and receiver operating characteristic curves to test associations with all-cause mortality. Mean age was 61 years and the mean estimated GFR was 41 ml/min per 1.73 m(2). Measures of lower extremity performance were at least 30% lower than predicted, but handgrip strength was relatively preserved. Fifty deaths occurred during the median 3-year follow-up period. After adjustment, each 0.1-m/s decrement in gait speed associated with a 26% higher risk for death, and each 1-second longer TUAG associated with an 8% higher risk for death. On the basis of the receiver operating characteristic analysis, gait speed and TUAG more strongly predicted 3-year mortality than kidney function or commonly measured serum biomarkers. Adding gait speed to a model that included estimated GFR significantly improved the prediction of 3-year mortality. In summary, impaired physical performance of the lower extremities is common in CKD and strongly associates with all-cause mortality.
authors.affiliation: Division of Nephrology, Department of Medicine, University of Washington Kidney Research Institute, Box 359606, 325 9th Avenue, Seattle, WA 98104, USA. broshanr@u.washington.edu
authors.forename: Baback
authors.initials: B
authors.lastname: Roshanravan
authors.forename: Cassianne
authors.initials: C
authors.lastname: Robinson-Cohen
authors.forename: Kushang V
authors.initials: KV
authors.lastname: Patel
authors.forename: Ernest
authors.initials: E
authors.lastname: Ayers
authors.forename: Alyson J
authors.initials: AJ
authors.lastname: Littman
authors.forename: Ian H
authors.initials: IH
authors.lastname: de Boer
authors.forename: T Alp
authors.initials: TA
authors.lastname: Ikizler
authors.forename: Jonathan
authors.initials: J
authors.lastname: Himmelfarb
authors.forename: Leslie I
authors.initials: LI
authors.lastname: Katzel
authors.forename: Bryan
authors.initials: B
authors.lastname: Kestenbaum
authors.forename: Stephen
authors.initials: S
authors.lastname: Seliger
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005684:Gait; D005919:Glomerular Filtration Rate; D018737:Hand Strength; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D051436:Renal Insufficiency, Chronic / Q000401:mortality*; D016138:Walking