Abstract P103: Impairment of Lower Extremity Physical Performance in Non-Dialysis CKD.
Background: Kidney dysfunction leads to the retention of metabolic waste products which may subsequently impair muscle function and physical performance.
Methods: We prospectively measured physical performance in 183 stroke-free older adults with stage 3-4 CKD to determine the pattern of functional impairment and the relationship of performance with severity of CKD. Functional tests included the short physical performance battery (SPPB), 4 meter walk (gait speed), 6 minute walk distance (6MWD), timed get up and go test (TGUAG), grip strength, and peak expiratory flow. Physical performance in the CKD cohort was compared to normative data obtained from 78 non-CKD controls for the TGUAG and to expected performance from published normative data for other performance measures. Among CKD subjects, associations of performance with eGFR and proteinuria were estimated using linear regression adjusting for age, sex, race, height, and weight.
Results: Mean eGFR was 34.8 ±12.5 mL/min/1.73m2, mean BMI 30.6 ±6 kg/m2, and median proteinuria 240 mg/g. Mean age was 66 ±7.7years, 91% were male, 33% African American, and 40% diabetic. CKD patients had significantly worse performance compared to predicted values on the TGUAG test (36 ±41% slower), gait speed (-31.7 ±15%), 6MWD (-31 ±15%), and peak expiratory flow (-25 ±34%). Among CKD subjects, lower eGFR and greater proteinuria were associated with worse performance on the 6MWD (Table). In contrast, no significant associations were observed between eGFR or proteinuria with performance on the other physical performance tests.
|Renal Function Measure||6 Meter Walk Distance (meters)|
|Units||β* (95%CI)||P value|
|GFRMDRD (mL/min/1.73m2)||10mL/min/1.73m2 decrement||−11.0 (-23.0, 1.1)||0.07|
|30-44||−7.0 (-38, 24)||.044|
|<30||−35 (-68, -1.3)|
|Proteinuria (mg/g Cr)||1 ln-increment||−11.0 (-21.1, -0.9)||0.033|
|≥300||−25.8 (-53, 1.38)||0.063|
↵* Adjusted for age, sex, race, height, and weight
Conclusions: Older adults with CKD exhibit markedly reduced physical performance, especially for tests of lower extremity function. Lower renal function and greater proteinuria are associated with worse performance on the 6-minute walk test, a measure of submaximal gait.
- © 2012 by American Heart Association, Inc.