Gait Abnormalities and the Risk of Falls in CKD

Abstract

Background and objectives: Older adults with CKD are at high risk of falls and disability. It is not known whether gait abnormalities contribute to this risk.

Design, setting, participants, & measurements: Quantitative and clinical gait assessments were performed in 330 nondisabled community-dwelling adults aged ≥65 years. CKD was defined as an eGFR <60 ml/min per 1.73 m². Cox proportional hazards models were created to examine fall risk.

Results: A total of 41% (n=134) of participants had CKD. In addition to slower gait speed, participants with CKD had gait cycle abnormalities including shorter stride length and greater time in the stance and double-support phases. Among people with CKD, lower eGFR was independently associated with the severity of gait cycle abnormalities (per 10 ml/min per 1.73 m² lower eGFR: 3.6 cm [95% confidence interval (95% CI), 1.4 to 5.8] shorter stride length; 0.7% [95% CI, 0.3 to 1.0] less time in swing phase; 1.1% [95% CI, 0.5 to 1.7] greater time in double-support phase); these abnormalities mediated the association of lower eGFR with slower gait speed. On clinical gait exam, consistent with the quantitative abnormalities, short steps and marked swaying or loss of balance were more common among participants with CKD, yet most had no identifiable gait phenotype. A gait phenotype defined by any of these abnormal signs was associated with higher risk of falls among participants with CKD: compared with people without CKD and without the gait phenotype, the adjusted hazard ratio was 1.72 (95% CI, 1.06 to 2.81) for those with CKD and the phenotype; in comparison, the adjusted hazard ratio was 0.71 (95% CI, 0.40 to 1.25) for people with CKD but without the phenotype (P value for interaction of CKD status and gait phenotype =0.01).

Conclusions: CKD in older adults is associated with quantitative gait abnormalities, which clinically manifest in a gait phenotype that is associated with fall risk.

Keywords: Accidental Falls; Gait; Independent Living; Phenotype; Proportional Hazards Models; Receptor, Epidermal Growth Factor; Renal Insufficiency, Chronic; Risk; Walking Speed; chronic kidney disease; eGFR protein, human; geriatric nephrology; glomerular filtration rate.

Graphical abstract

Figure 1.

Gait cycle abnormalities may increase fall risk in CKD. Gait cycle abnormalities could be present in older adults with CKD because of several sequelae of CKD that affect physical function. If present, gait cycle abnormalities could be an important contributor to fall risk. *The presence of cerebrovascular disease was not directly tested in this study.

Figure 2.

Lower eGFR is associated with greater abnormalities in quantitative gait markers. Linear regression models were used to calculate age- and sex-adjusted differences in gait speed (A), stride length (B), percent of the gait cycle spent in the swing phase (C) and double-support phase (D), stride length variability (E), and cadence (F). Reference category for each comparison is eGFR >75 ml/min per 1.73 m².