The association between white matter hyperintensity volume and cognitive/physical decline in older people with dementia: A one-year longitudinal study

Abstract

Objectives

Understanding the relationship between white matter hyperintensities (WMHs) and cognitive and physical decline in people with dementia will assist in determining potential treatment strategies. Currently there is conflicting evidence describing the association between WMHs and cognitive decline and, WMHs association with declines in objective measures of physical function have not been examined. We examined the relationship between baseline WMH volume and physical/cognitive decline over one-year in older people with dementia.

Methods

Twenty-six community-dwelling older people with dementia (mean age = 81 ± 8 years; 35% female) were assessed at baseline and follow-up (one-year) using the Addenbrooke’s Cognitive Examination-Revised (including verbal fluency), Trail Making Test A, the Physiological Profile Assessment (PPA), timed-up-and-go (TUG) and gait speed. WMH volumes were quantified using a fully automated segmentation toolbox, UBO Detector.

Results

In analyses adjusted for baseline performance, higher baseline WMH volume was associated with decline in executive function (verbal fluency), sensorimotor function (PPA) and mobility (TUG). Executive function (semantic/category fluency) was the only domain association that withstood adjustment for age, and additionally hippocampal volume.

Conclusions

In unadjusted analyses, WMH volume was associated with one-year declines in cognitive and physical function in older people with dementia. The association with executive function decline withstood adjustment for age. More research is needed to confirm these findings and explore whether vascular risk reduction strategies can reduce WMH volume and associated cognitive and physical impairments in this group.

Keywords:

• leukoaraiosis
• cerebral small vessel diseases
• cognitive dysfunction
• physical functional performance
• Alzheimer disease

Acknowledgements

We would like to acknowledge the participants, their families and caregivers. We would also like to acknowledge A. Stefanie Mikolaizak for her contribution to data acquisition.

Disclosure statement

The Physiological Profile Assessment (FallScreen) is commercially available through Neuroscience Research Australia.

Author contributions

JCTC, MET and SRL were involved in the study design. MT was responsible for data acquisition. WW and JJ were responsible for MRI processing. MET, JCTC and RH were responsible for the research questions. RH and MET were responsible for the data analysis. RH and MET drafted the manuscript. All authors were involved in interpreting the data and revising the manuscript.

Additional information

Funding

This work was supported by the Australian National Health and Medical Research Council (NHMRC) (grant number 455368). Prof Stephen Lord is a NHMRC Senior Principal Research Fellow. Dr Morag Taylor is partially funded by the NHMRC Centre of Research Excellence in the Prevention of Fall-related Injuries.