Changes in gait function associated with cerebral small vessel disease-related cognitive impairment during dual-task walking: a systematic review and meta-analysis

Cerebral small vessel disease (CSVD) is a major contributor to vascular cognitive impairment. As gait abnormalities emerge early in the disease course and are closely related to cognitive decline, quantitative gait assessment offers a promising approach for the early detection of CSVD-related cognitive impairment (CSVD-CI). Dual-task (DT) gait assessment increases cognitive demands during walking and may reveal cognitive-motor deficits that are less apparent under single-task (ST) conditions. However, heterogeneity in gait metrics, imaging criteria, and cognitive paradigms has resulted in inconsistent findings, thereby impeding the identification of robust gait markers for CSVD-CI. A systematic search of PubMed, Web of Science, Scopus, and EBSCO identified nine studies reporting DT gait outcomes and eight reporting ST gait outcomes in patients with CSVD-CI, with four studies reporting outcomes under both conditions. Compared with ST conditions, DT gait assessment more effectively discriminated patients with CSVD-CI from cognitively unimpaired controls. Under DT conditions, CSVD-CI patients exhibited significantly slower gait speed (p = 0.014), greater stride time variability (p = 0.027), and higher dual-task costs (p < 0.001), suggesting a slower and less stable gait pattern. Subgroup and sensitivity analyses suggested that CSVD imaging characteristics may contribute to between-study heterogeneity, although these findings remain exploratory. These findings support further investigation of selected DT gait parameters as potential behavioral indicators of CSVD-CI. Further studies in CSVD populations defined using standardized diagnostic and inclusion criteria should evaluate the screening performance and longitudinal predictive value of DT gait parameters, as well as their associations with CI severity.