Association of peripheral artery disease with life-space mobility restriction and mortality in community-dwelling older adults

Abstract

ObjectiveSymptomatic peripheral artery disease (PAD) impairs walking, but data on the impact of PAD on community mobility is limited. Life-space mobility measures the distance, frequency, and assistance needed as older adults move through geographic areas extending from their bedroom (life-space mobility score: 0) to beyond their town (life-space mobility score: 120). We evaluated the association of PAD with longitudinal life-space mobility trajectory. MethodsParticipants were part of the University of Alabama at Birmingham Study of Aging, a longitudinal study of community-dwelling older adults who were observed from 2001 to 2009. We limited our analysis to those who survived at least 6 months (N = 981). PAD was based on self-report with verification by physician report and hospital records. Our primary outcome was life-space mobility score assessed every 6 months. A multilevel change model (mixed model) was used to determine the association between PAD and life-space mobility trajectory during a median 7.9 years of follow-up. ResultsParticipants had a mean age of 75.7 (standard deviation, 6.7) years; 50.5% were female, and 50.4% were African American. PAD prevalence was 10.1%, and 57.1% of participants with PAD died. In participants with both PAD and life-space restriction, defined as life-space mobility score <60, we observed the highest mortality (73.1%). In a multivariable adjusted mixed effects model, participants with PAD had a more rapid decline in life-space mobility by −1.1 (95% confidence interval [CI], −1.9 to −0.24) points per year compared with those without PAD. At 5-year follow-up, model-adjusted mean life-space mobility was 48.1 (95% CI, 43.5-52.7) and 52.4 (95% CI, 50.9-53.8) among those with and without PAD, respectively, corresponding to a restriction in independent life-space mobility at the level of one's neighborhood. ConclusionsLife-space mobility is a novel patient-centered measure of community mobility, and PAD is associated with significant life-space mobility decline among community-dwelling older adults. Further study is needed to mechanistically confirm these findings and to determine whether better recognition and treatment of PAD alter the trajectory of life-space mobility.