Community mobility among older adults with reduced kidney function: a study of life-space.
BACKGROUND
Life-Space Assessment captures community mobility and social participation and quantifies the distance, frequency, and independence obtained as an older adult moves through his or her environment. Reduced estimated glomerular filtration rate (eGFR) is associated with decline in activities of daily living among older adults, but less is known about the association of eGFR with restrictions in mobility.


METHODS
Prospective observational cohort study.


METHODS
Community-dwelling Medicare beneficiaries from the University of Alabama at Birmingham Study of Aging who had serum creatinine measured during a baseline in-home study visit and completed at least one telephone follow-up (N = 390).


METHODS
eGFR ≥ 60, 45-59, and <45 mL/min/1.73 m(2).


RESULTS
Life-space mobility trajectory.


METHODS
Life-space mobility was evaluated by telephone every 6 months for up to 4.5 years using the previously validated Life-Space Assessment. Scores using this tool range from 0-120 (higher scores indicate greater mobility).


RESULTS
Mean age of the 390 participants was 77.6 ± 5.8 (SD) years, 41% were African American, 50.5% were women; 30.0% had eGFR of 45-59 mL/min/1.73 m(2), and 20.2% had eGFR < 45 mL/min/1.73 m(2). Age-, race-, and sex-adjusted mean baseline life-space mobility scores were 64.8(95% CI, 62.0-67.6), 63.8 (95% CI, 60.3-67.4), and 58.3 (95% CI, 53.8-62.7) among those with eGFR categories ≥ 60, 45-59, and <45 mL/min/1.73 m(2), respectively. Compared with those with eGFRs ≥ 60 mL/min/1.73 m(2), a more rapid decline in life-space mobility was found among those with eGFRs < 45 mL/min/1.73 m(2), though this did not reach statistical significance (P=0.06); a similar effect was not seen among those with eGFRs of 45-59 mL/min/1.73 m(2) (P=0.3).


CONCLUSIONS
Urinary albumin or longitudinal measures of eGFR were not available.


CONCLUSIONS
eGFR < 45 mL/min/1.73 m(2) was associated with a trend toward a more rapid decline in life-space mobility among community-dwelling older adults. Findings should be confirmed in a larger population.
Birmingham/Atlanta Geriatric Research, Education, and Clinical Center, Department of Veterans Affairs Medical Center, Birmingham, AL; Division of Gerontology, Geriatrics and Palliative Care, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL. Electronic address: cbbowli@emory.edu.
C Barrett
CB
Bowling
Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, AL.
Paul
P
Muntner
Division of Gerontology, Geriatrics and Palliative Care, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL.
Patricia
P
Sawyer
Division of Nephrology, Department of Medicine, University of Alabama at Birmingham and Department of Veterans Affairs Medical Center, Birmingham, AL.
Paul W
PW
Sanders
Department of Rehabilitation Medicine, Emory University, Atlanta, GA.
Nancy
N
Kutner
Division of Gerontology, Geriatrics and Palliative Care, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL.
Richard
R
Kennedy
Birmingham/Atlanta Geriatric Research, Education, and Clinical Center, Department of Veterans Affairs Medical Center, Birmingham, AL; Division of Gerontology, Geriatrics and Palliative Care, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL.
Richard M
RM
Allman
D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006801:Humans; D008124:Locomotion / Q000502:physiology*; D008297:Male; D051346:Mobility Limitation; D011446:Prospective Studies; D051437:Renal Insufficiency / Q000503:physiopathology*; D013997:Time Factors
Chronic kidney disease; elderly; life-space mobility