Performance variance on walking while talking tasks: theory, findings, and clinical implications.
Dual tasks that involve walking and cognitive interference tests are commonly used in mobility assessments and interventions. However, factors that explain variance in dual-task performance costs are poorly understood. We, therefore, examined the moderating effects of two putative constructs, postural reserve and hazard estimate, on performance on a walking while talking paradigm. Participants were 285 non-demented older adults (mean age = 76.9 years; %female = 54.4). Postural reserve was operationalized as the presence or absence of clinical gait abnormalities. An empirical factor, based on measures of executive functions, served as a marker for hazard estimate. The moderation effects of postural reserve and hazard estimate on dual-task costs were examined via two-way interactions in a joint linear mixed effect model. Significant dual-task costs were observed for gait speed (95% CI = 30.814 to 39.121) and cognitive accuracy (95% CI = 6.568 to 13.607). High hazard estimate had a protective effect against decline in gait speed (95% CI = -8.372 to -0.151) and cognitive accuracy (95% CI = -8.372 to -0.680). Poor postural reserve was associated with reduced decline in gait speed (95% CI = -9.611 to -0.702) but did not moderate the decline in cognitive accuracy (95% CI = -3.016 to 4.559). Assessing postural reserve and hazard estimate can help improve mobility risk assessment procedures and interventions for individuals with cognitive and movement disorders.
Ferkauf Graduate School of Psychology, Yeshiva University, New York, NY, USA, roee.holtzer@einstein.yu.edu.
Roee
R
Holtzer
Cuiling
C
Wang
Joe
J
Verghese
D000368:Aged; D000369:Aged, 80 and over; D001288:Attention / Q000502:physiology*; D056344:Executive Function / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D013060:Speech; D013647:Task Performance and Analysis; D016138:Walking / Q000502:physiology*