Citation

Reelick MF, Kessels RP, Faes MC, Weerdesteyn V, Esselink RAJ, Olde Rikkert MG. Aging Clin. Exp. Res. 2010; 23(5-6): 393-399.

Affiliation

Radboud University Nijmegen Medical Centre, Department of Geriatric Medicine, The Netherlands. M.Reelick@ger.umcn.nl.

Copyright

(Copyright © 2010, Holtzbrinck Springer Nature Publishing Group)

DOI

10.3275/7327

PMID

21048423

Abstract

Aims: To study and compare both the mean performance measures as well as the intra-individual variability measures of stride length and reaction time in vulnerable recurrent and non-recurrent older fallers. Methods: Stride length during walking, and walking while dual-tasking (GAITRite®), and choice reaction time (CANTAB®) were assessed in geriatric outpatients and their informal caregivers (N=60, ≥60 yrs). Using logistic regression and Receiver Operating Characteristic (ROC) analysis, models were obtained with mean performance measures and with intra-individual variability measures (coefficients of variation; CV=[sd/mean]x100)), as risk factors for recurrent falls. Results: Reaction-time CV was higher in recurrent fallers compared to non-recurrent fallers: 21.3% [9.3-47.7] versus 15.8% [8.3-34.9] (p=0.04). Also, stride-length CV was higher in recurrent fallers during performance of the verbal fluency dual-task: 4.5% [1.2-31.4] versus 3.5% [0.9-9.7] (p=0.017). The model with CVs provided an explained variance of 23.7%, and an area under the curve (AUC) of 0.73, which was higher than the model including the mean performance measures (8.6% and 0.65 respectively). Conclusions: Older recurrent fallers are characterized by increased within-task variability in reaction time and stride length while dual-tasking. Moreover, variability in performance is a more sensitive measure in discrimination of recurrent falls than the mean performance itself, suggesting deterioration in neurocognitive regulation mechanisms as part of the causal pathway for recurrent falls.

Language: en