Neurology: spatial navigation in dementia-free memory clinics and its relationship to biomarkers and future dementia

Spatial navigation disorders are considered an early sign
of many neurodegenerative diseases.
A study published in Neurology seeks to determine whether spatial navigation is associated with future dementia in patients with subjective cognitive decline (SCD) or mild cognitive impairment (MCI), and to explore the association
between spatial navigation and biomarkers of Alzheimer's disease (AD) and neurodegenerative diseases.

The study included memory outpatients
without dementia in a longitudinal BioFINDER cohort.
The Floor Maze Test (FMT) is used to evaluate spatial navigation
at baseline.
Dementia conversion rates
were assessed at 2- and 4-year follow-up.
At baseline, amyloid-β42/40 ratios, phosphorylated tau (p-tau), and neurofilament light (NfL)
are analyzed in cerebrospinal fluid.
MRI quantifies cortical thickness and volume of navigation in relevant areas and white matter lesion volume
.
Through the Logit model analysis of two models, the predictive effect of FMT on all-cause dementia was analyzed: 1) control age, sex and education level; 2) Increase baseline cognitive status and MMSE
.
The correlation between FMT and biomarkers is adjusted
for age, sex, and cognitive status (SCD or MCI).

Among them, 156 patients with SCD and 176 patients with MCI
.
Total FMT time was associated with all-cause dementia progression at 2 years (OR 1.
10, 95% CI 1.
04, 1.
16) and 4-year follow-up (OR 1.
10, 95% CI 1.
04, 1.
16) in model 2, i.
e.
, a 10%
increase in the chance of dementia for every additional 10 seconds of FMT.
In the adjusted analysis, P-tau and NfL correlated
with total FMT time, as well as hippocampal volume, parahippocampal and inferior parietal cortex thickness.
The amyloid-β42/40 ratio is independent
of total FMT time.

Impaired spatial navigation is associated with transformation to dementia at 2 and 4 years and is associated
with key cerebrospinal fluid and MRI biomarkers of AD and neurodegenerative diseases in patients with SCD and MCI.
This supports its application in early cognitive assessments, but the accuracy of the predictions should be verified
in other cohorts.

This is a category 1 prospective cohort study demonstrating the association
of baseline spatial recognition of baseline markers with the development of dementia at baseline in patients with SCD or MCI.

Source: Tangen GG, Nilsson MH, Stomrud E, Palmqvist S, Hansson O.
Spatial Navigation and Its Association With Biomarkers and Future Dementia in Memory Clinic Patients Without Dementia [published].
online ahead of print, 2022 Aug 26].
Neurology.
2022; 10.
1212/WNL.
0000000000201106.
doi:10.
1212/WNL.
0000000000201106