The effects of tau, amyloid and white matter lesions on mobility, dual tasking and balance in older people

Sammendrag på engelsk (abstract):
Background
This study aimed to investigate whether white matter lesions (WML), β-amyloid- and tau pathologies are independently associated with mobility, dual tasking and dynamic balance performance in older non-demented individuals.
Methods
We included 299 older people (mean, SD, age: 71.8, 5.6 years) from the Swedish BioFINDER study, whereof 175 were cognitively unimpaired and 124 had mild cognitive impairment (MCI). In multivariable regression analyses, dependent variables included mobility (Timed Up & Go, TUG), dual tasking (TUG with a simultaneous subtraction task, i.e. TUG-Cog, as well as dual task cost), and balance (Figure-of-eight). The analyses were controlled for age, sex, education, diagnosis (i.e. MCI) and comorbidity (stroke, diabetes, and ischemic heart disease). Independent variables included WML volume, and measures of β-amyloid (abnormal CSF Aβ42/40 ratio) and tau pathology (CSF phosphorylated tau, p-tau).
Results
Multivariable regression analyses showed that an increased WML volume was independently associated with decreased mobility, i.e. TUG (standardized β=0.247; p<0.001). Tau pathology was independently associated with dual tasking both when using the raw data of TUG-Cog (β=0.224; p=0.003) and the dual task cost (β= -0.246; p=0.001). Amyloid pathology was associated with decreased balance, i.e. Figure-of-eight (β= 0.172; p=0.028). The independent effects of WML and tau pathology were mainly observed in those with MCI, which was not the case for the effects of amyloid pathology on balance.
Conclusions
Common brain pathologies have different effects where WML are independently associated with mobility, tau pathology has the strongest effect on dual tasking and amyloid pathology seems to be independently associated with balance. Although these novel findings need to be confirmed in longitudinal studies, they suggest that different brain pathologies have different effects on mobility, balance and dual tasking in older non-demented individuals.

Maria H Nilsson, Gro Gujord Tangen, Sebastian Palmqvist, Danielle van Westen, Niklas Mattsson-Carlgren, Erik Stomrud, Oskar Hansson

OPEN ACCESS