Role of gait and speed performance in predicting cognitive decline and dementia in people with Down syndrome: Preliminary findings

Abstract

Background The longevity of people with DS has increased substantially in recent decades. This population shows signs of premature aging in many organs and systems. The neuropathology of Alzheimer's disease (AD) is overexpressed in DS. Cognitive and functional losses, such as decline in executive function and apraxia, interfere with the sequencing of movements and the integrity of gait. There is evidence that a decrease in gait may precede other clinical symptoms of dementia in AD in the general population, but we found no studies investigating gait performance and decline in DS. The aim of this study is to characterize gait and speed performance in a sample of adults with DS divided into three groups by diagnosis: stable cognition, prodromal dementia and AD. Methods We used the Performance Oriented Mobility Assessment (POMA) to address balance, gait and the risk of falls and the Timed “Up and Go” test (TUG) to assess gait speed in a sample of 35 individuals with DS over 35 years of age. Dementia diagnosis was based on the Cambridge Examination for Mental Disorders of Older People with Down’s Syndrome and Others with Intellectual Disabilities (CAMDEX‐DS). The 1‐factor, 3‐level ANOVA model was used in the 3 groups. Results 9 participants (25.7%) had AD (mean POMA 12.0 ± 7.1; mean TUG 18.0 ±5.8), 8 (22.9%) were classified as prodromal dementia (mean POMA 19.0 ± 5.6; mean TUG 21.0± 6.1) and 18 (51.4%) were in the stable cognition group (mean POMA score 20 ± 4.5; mean TUG 17.0 ±5.5). Mean POMA scores were significant different among the groups (p<0.05) with higher impairment in the group with AD relative to those with prodromal dementia and stable cognition. We did not find difference for the TUG scores among the groups. Conclusions POMA results indicates that those with AD have worse balance, gait performance and higher risk of falls relative to those with prodromal dementia and stable cognition, suggesting that gait performance may be more affected in later stages of neurodegeneration. Gait speed does not seem to be useful differentiating the groups. Further longitudinal studies with bigger samples are needed to confirm our results.

Down syndrome and Alzheimer's disease: A scoping review of functional performance and fall risk

“…There is a need to explore functional measures such as fall risk, fall incidents, and functional mobility to gain a better understanding of the role they play in the progression of AD in DS 1,8,9 . Falls and functional mobility are associated with clinical measures of cognition and are a non‐cognitive behavioral biomarker of preclinical AD and AD 9,16,18,29 . A better understanding of falls and functional mobility could inform the non‐cognitive biomarker profile in adults with DS through a direct and less‐invasive method of assessment, thus reducing the burden for both the participant and caregivers 5,9,51 …”

“…For example, falls and functional mobility are associated with clinical measures of cognition and may be a non-cognitive behavioral marker of AD. [14][15][16][17][18] A fall is an unexpected event in which a person comes to rest on the ground, floor, or a lower level. 9 Although individuals with DS have a higher rate of falls, it remains unknown when falls occur in the progression of AD in adults with DS.…”

“…1,8,9 Falls and functional mobility are associated with clinical measures of cognition and are a non-cognitive behavioral biomarker of preclinical AD and AD. 9,16,18,29 A better understanding of falls and functional mobility could inform the non-cognitive biomarker profile in adults with DS through a direct and less-invasive method of assessment, thus reducing the burden for both the participant and caregivers. 5,9,51…”

“…There is limited evidence on the lived experiences and daily functional performance of adults aging with DS, when changes in functional activity and performance occur, and the significance of those changes to disease staging in relation to ADRD. For example, falls and functional mobility are associated with clinical measures of cognition and may be a non‐cognitive behavioral marker of AD 14–18 . A fall is an unexpected event in which a person comes to rest on the ground, floor, or a lower level 9 .…”

Balance and Gait

“…The Timed Up and Go (TUG) test was developed in 1986 by Mathias et al 24 The test requires the patient to get up from a chair, walk a short distance, turn around, return, and sit down again. The TUG test has proven to be a satisfactory clinical measure of balance in aging individuals with DS 25 . Richardson and Podsiadlo 26 developed the modified and timed version of the test, suggesting that it is a valid, reliable test to quantify functional mobility and that it can be useful in monitoring clinical changes over time for the general population 27,28 …”