Dual decline in gait speed and cognition increases dementia risk in seniors: JAMA

Australia: A combination of the decline in gait speed with memory is strongly associated with the risk of dementia in older adults, states an article published in JAMA Network Open.

Globally, around 55 million people are reported to have dementia, of which 5.3 million are Indians aged >60 and this number is projected to increase in the future. Individuals at-risk must be identified to address modifiable risk factors and provide available interventions. Previous studies showed a dual decline in gait speed and cognition is associated with increased dementia risk but it is not clear if risks are conferred by a decline in domain-specific cognition and gait.

Taya A., Monash University, Australia, and her team conducted a cohort study to examine associations between the dual decline in gait speed and cognition and with risk of dementia. The study used data from 16 855 relatively healthy seniors in Australia and the US who had participated in a randomized clinical trial testing low-dose aspirin (2010 – 2017).

Gait speed was measured at 0, 2, 4, and 6 years and at trial close-out, and gait decline was defined as a decline in the speed of 0.05 m/s or greater per year across the study. Cognitive measures included Modified Mini-Mental State Examination (3MS) for global cognition, Hopkins Verbal Learning Test-Revised (HVLT-R) for memory, Symbol Digit Modalities (SDMT) for processing speed, and Controlled Oral Word Association Test (COWAT-F) for verbal fluency, assessed at years 0, 1, 3, 5, and close-out. Cognitive decline was defined as members of the lowest tertile of annual change.

Participants were classified into 4 groups: dual decline in gait and cognition, gait decline only, cognitive decline only, and nondecliners. Cox proportional hazard models were used to estimate the risk of dementia adjusting for covariates, with death as a competing risk.

Key findings of the study,

• Compared to non-decliners, the risk of dementia was highest in participants who showed a decline in both gait and memory( HR- 24.7), followed by the gait and global cognition (HR-22.2), gait and verbal fluency (HR-4.7), and gait and processing speed (HR-4.3).

• Dual decliners had a higher risk of dementia than those with either gait or cognitive decline alone for global cognition and memory.

Researchers conclude that a dual decline in gait speed and cognition was associated with an increased risk of dementia, with dual memory decliners showing the greatest risk.

The study further provides evidence for adding serial gait speed measures to dementia risk screening assessments, providing the opportunity for further comprehensive assessment and early preventative treatment.

Reference:

Collyer TA, Murray AM, Woods RL, et al. Association of Dual Decline in Cognition and Gait Speed With Risk of Dementia in Older Adults. JAMA Netw Open. 2022;5(5):e2214647. doi:10.1001/jamanetworkopen.2022.14647