Increased postural sway during quiet stance as a risk factor for prospective falls in community-dwelling elderly individuals

Abstract

Objective: fall-related injuries constitute major health risks in older individuals, and these risks are projected to increase in parallel with increasing human longevity. Impaired postural stability is a potential risk factor related to falls, although the evidence is inconclusive, partly due to the lack of prospective studies. This study aimed to investigate how objective measures of postural sway predict incident falls.

Design, setting and participants: this prospectively observational study included 1,877 community-dwelling individuals aged 70 years who participated in the Healthy Ageing Initiative between June 2012 and December 2015.

Measurements: postural sway was measured during eyes-open (EO) and eyes-closed (EC) trials using the Wii Balance Board. Functional mobility, muscle strength, objective physical activity and cognitive performance were also measured. Participants reported incident falls 6 and 12 months after the examination.

Results: during follow-up, 255 (14%) prospective fallers were identified. Division of centre of pressure (COP) sway lengths into quintiles revealed a nonlinear distribution of falls for EO trial data, but not EC trial data. After adjustment for multiple confounders, fall risk was increased by 75% for participants with COP sway lengths ≥400 mm during the EO trial (odds ratio [OR] 1.75, 95% confidence interval [CI] 1.09-2.79), and approximately doubled for sway lengths ≥920 mm during the EC trial (OR 1.90, 95% CI 1.12-3.22).

Conclusion: objective measures of postural sway independently predict incident falls in older community-dwelling men and women. Further studies are needed to evaluate whether postural sway length is of interest for the prediction of incident falls in clinical settings.

Keywords: cohort study; incident fall; older people; postural sway; posturography.