Association between gait speed decline and EEG abnormalities in a cohort of active older adults living in the community.

Background: age-related gait speed decline is associated with pathological brain changes. Despite EEG sensitivity for detecting alteration in the brain function, its clinical use to evaluate walking disorders is rare. In this study, we examined the association of subclinical gait speed deterioration in older individuals with changes in the EEG frequency composition as a marker of mild cerebral dysfunction. Methods: we studied the gait speed of 90 physically active, community-dwelling older adults in two different appointments separated by an interval of 6 years. In the last assessment, resting-state EEG was acquired in all participants. After a visual clinical report, the EEG was transformed to the frequency domain, and the energy of each frequency band was compared against normative data. Results: 63 of 90 older individuals had gait speed deterioration, 87% of which also had an abnormal EEG frequency composition. EEG abnormalities were characterised by an increase in delta and theta bands power, higher than that expected for their age. We found some participants with gait speed decline that also had a decrease in alpha band power. EEG sensitivity for classifying participants with a deterioration in gait speed was 0.86, with a likelihood ratio of 2.9. Conclusions: the subclinical gait speed decline found in this cohort was associated with significant changes in resting-state EEG frequency composition. The sensitivity of EEG frequency abnormalities for identifying older individuals with deterioration in gait speed supports its inclusion in the assessment pathway of older individuals at risk of developing gait disorders.