A combined stepping and visual tracking task predicts cognitive decline in older adults better than gait or visual
Yosuke Osuka1, Hunkyung Kim2, Yutaka Watanabe3
1Research Team for Promoting Independence and Mental Health, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan. osuka@tmig.or.jp.
Background:
It is unclear whether motor-cognitive dual tasks predict cognitive decline better than either motor or cognitive tasks alone.
Aims:
To examine the utility of the novel motor-cognitive dual-task test [Stepping Trail Making Test (S-TMT)], as a predictor of cognitive decline, and compare its predictive performance with single motor or cognitive tests.
Methods:
This 2-year population-based prospective study included 626 adults aged ≥ 70 years from Takashimadaira, Itabashi, Tokyo. The S-TMT measured the time taken to step on 16 numbers in order. Gait speed and TMT-A were assessed with standardized methods as single motor and cognitive tasks, respectively. A decline in the Mini-Mental State Examination score by ≥ 3 points over 2 years was defined as a significant cognitive decline.
Results:
Over 2 years, 97 (15.5%) experienced cognitive decline. After adjusting for confounders, binary logistic regression models showed no significant associations between gait speed, TMT-A time tertiles, and risk of cognitive decline, but participants in the longest tertile of S-TMT time were more likely to develop cognitive decline than those of the shortest tertile (odds ratio 2.14; 95% confidence interval 1.17-3.90). Only the addition of the S-TMT time to the covariates model significantly improved the reclassification indices for predicting cognitive decline (net reclassification improvement: 0.31, P < 0.01; integrated discrimination improvement: 0.01, P = 0.02).
Discussion And Conclusion:
Only the S-TMT was significantly associated with cognitive decline and improved reclassification indices, indicating that it is more useful for predicting cognitive decline than individual gait speed or visual tracking tests alone.
