Falls: A Marker of Preclinical AD

Study Overview
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Brief Summary
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This longitudinal cohort study investigates cognitively normal participants with and without preclinical Alzheimer disease (AD) in order to examine: (1) the relationship between falls and functional mobility in preclinical stages of AD; and (2) a hypothesized model of central and peripheral mechanism(s) underlying falls and functional mobility in preclinical stages of AD.

Detailed Description
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Alzheimer disease (AD) is a slowly progressive neurodegenerative disease. Conversion to symptomatic AD occurs slowly over years through a series of preclinical stages marked by changes in molecular biomarkers. It is unknown whether functional mobility and falls are preclinical markers of AD. This longitudinal clinical study evaluates a cohort of cognitively normal individuals who are currently undergoing comprehensive clinical, neuropsychological, and biomarker evaluations at the Knight Alzheimer's Disease Research Center (Knight ADRC). They receive an annual in-home evaluation of fall risks and functional mobility and prospective ascertainment of falls. Comparisons of assessments of functional mobility will be performed with regard to measures of brain pathology (i.e., amyloidosis, tau, and neurodegeneration) to allow researchers to characterize when changes in falls and functional mobility occur during preclinical stages of AD. This study also examines the central and peripheral system mechanism(s) underlying falls and functional mobility in preclinical AD using structural equation modeling.

Official Title
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Falls: A Marker of Preclinical Alzheimer Disease

Conditions
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Fall, Alzheimer Disease

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 65 years of age or older cognitively normal (Clinical Dementia Rating [CDR] score of 0) A pilot sub-study collecting stool will also enroll a few individuals with CDR>0 for comparison. have biomarkers (CSF), and/or neuroimaging (positron emission tomography [PET] and/or magnetic resonance imaging [MRI]) within 2 years of enrolling in this study. Exclusion Criteria: History of Parkinson's disease.

Ages Eligible for Study
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Minimum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number and Severity of Falls | Prospective monthly fall reporting will be collected using an automated phone/email system. Severity of falls will be calculated using a previously published algorithm. | Cumulative falls at 4 years post-enrollment | 
| Change from baseline: Dynamic balance and mobility | Dynamic balance and mobility will be assessed using the Performance Oriented Mobility Assessment (POMA), a task-oriented assessment. | 4 years post-enrollment | 
| Change from baseline: Gait Speed | Gait speed will be collected using the Timed Up and Go (TUG) test. | 4 years post-enrollment | 
| Change from baseline: Dual-task gait | Dual-task gait will be collected using the Timed Up and Go Cognitive (TUGcog) and Timed Up and Go Manual (TUGman) | 4 years post-enrollment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fall Risk Composite Score | A fall risk composite score will be calculated using established cut-off values, dichotomized as 0 (no risk), or 1 (fall risk), and summed. Higher score indicate higher fall risk. Constructs that will be included are: vision, alcohol abuse, urinary incontinence, depression, pain, medication, functional capacity with activities of daily living, previous falls, home hazards, and self-efficacy. | 4 years post-enrollment | 
| Change from baseline: Standing balance and vestibular function | Center of pressure path will be measured using Balance Tracking System (BTrackS) | 4 years post-enrollment | 
| Change from baseline: Lower extremity strength | Lower extremity strength will be assessed using the 30-Second Chair Stand test and minimal change in the peak torque value | 4 years post-enrollment | 
| Change from baseline: Grip strength | Pounds of force will be measured using a handheld dynamometer | 4 years post-enrollment | 
| Change from baseline: Vision | Visual acuity will be collected using the Early Treatment Diabetic Retinopathy Study (ETDRS) test, and contrast sensitivity will be measured using the Pelli-Robson test | 4 years post-enrollment | 
| Change from baseline: Sensation | 8-item questionnaire and sensation testing (vibration [feet] and sharp [arms and legs]) | 4 years post-enrollment | 
| Change from baseline: Depression | Frequency of symptoms will be assessed using The Patient Health Questionnaire (PHQ-9) and Geriatric Depression Scale (GDS) | 4 years post-enrollment | 
| Change in baseline: Functional performance | Independence, safety, and adequacy with shopping, checkbook balancing, and medication management will be assessed using the Performance Assessment of Self-Care Skills (PASS) | 4 years post-enrollment | 
| Change from baseline: Falls behavior | Behaviors to prevent falls will be measured using the Falls Behavioral Scale for Older People (FaB) | 4 years post-enrollment | 
| Change from baseline: Olfaction | Olfaction will be assessed using the University of Pennsylvania Smell Identification Test (UPSIT) | 2 years post-enrollment | 
| Change from baseline: Hearing | Hearing impairment will be assessed using The Hearing Handicap Inventory for the Elderly (HHIE-S) | 4 years post-enrollment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Preclinical Alzheimer Disease, Falls, Functional Mobility, Older Adults