A longitudinal study of gait on fall risk and disease progression in patients with mild cognitive impairment and Alzheimer's disease

Background The evaluation of gait has gained popularity in clinical practice due to its sensitivity for identifying functional decline and fall risk in numerous patient populations. Specific to Alzheimer’s Disease (AD), previous research has shown higher risk of falls and increased disability when compared to their healthy counterparts. However, gait biomarkers that can predict fall risk, disability and disease progression in those with AD have not been adequately quantified. A better characterization of longitudinal gait changes in patients with dementia could have implications for future research and targeted interventions aimed to identify and lessen fall risk as well as the related disability. Methods Gait outcomes, including gait speed, step length variability and step symmetry were collected at two timepoints using an instrumented ProtoKinetics Gait Mat. Each gait collection was linked to the electronic medical record in order to obtain a disease diagnosis and fall history. Results The final sample included 70 patients that were classified as mild cognitive impairment (MCI) at gait timepoint 1 and remained MCI at gait timepoint 2 (MCI‐MCI), 84 patients that were classified as AD at gait timepoint 1 and remained AD (AD‐AD) and 17 that were classified as MCI at gait timepoint 1 and subsequently transitioned to AD at gait timepoint 2 (MCI‐AD). Across the groups, gait speed was significantly slower in those with a history of falls when compared to those without a fall history ( p <0.05). Fall rates were highest in the AD‐AD group (41%). At gait timepoint 1, there was no significant difference in age or MOCA between the MCI‐MCI and MCI‐AD groups, however, fall rates were higher for those that transitioned from MCI to AD (24%) versus those that remained MCI from timepoint 1 to 2 (16%). Conclusion The results demonstrate there is a high risk of falls among patients with AD and those that transition from MCI to AD. A slower gait speed was associated with higher fall risk across groups. The significant rate of falls highlights the need for targeted interventions as falls are associated with increased disability, hospitalization and mortality.