Physical Function Assessment in Older Hemodialysis Patients

Abstract Rationale/Objective Physical function is not routinely measured in older adults receiving dialysis. We evaluated the appropriateness of repeated measurements of physical function, including short physical performance battery (SPPB), handgrip strength, and activities of daily living (ADLs) in older adults receiving dialysis. Study Design Prospective study Setting & Participants 37 community-dwelling adults aged ≥65 years receiving in-center hemodialysis at 5 dialysis units located in North Carolina Exposures SPPB (an assessment of standing balance, chair stands, and gait speed), handgrip strength, Katz and Lawton ADLs at baseline and subsequent 3-month intervals up to six months Outcomes Completion rate, presence of floor or ceiling effects, and presence of clinically meaningful change in physical function measures Results Of 55 potential subjects, we enrolled 37 (67%) older adults receiving hemodialysis. Among 35 enrolled participants who completed baseline assessment in a dialysis unit, mean (SD) age was 70.1 (5) years, 46% (n=16) were women, 77% (n=27) were African-American, and median (interquartile range) time on dialysis was 2.7 (0.6-5.0) years. There were three deaths within the observation period, and study retention at 3 months and 6 months was 83% (n=29) and 74% (n=26), respectively. Participants tolerated measurements; only two participants did not attempt one of the performance-based tests at a study visit. Baseline median (interquartile range) SPPB, grip strength, and gait speed were 6 (4-9), 55 (42-70) kg, and 0.76 (0.46-0.86) m/s, respectively. Baseline median (interquartile range) for Katz and Lawton ADLs were 6(6-6) and 7(4-8), respectively; ceiling effects were observed for both measures. For some participants, clinically meaningful changes (improvement or decline) in SPPB, grip strength, and gait speed occurred at each 3-month interval. Limitations Limited geographic and ethnic variation Conclusions SPPB, handgrip strength, and gait speed alone are appropriate measures for interval physical function assessment in community-dwelling older adults receiving in-center hemodialysis.