Dose Response Study of Aerobic Exercise in Older Adults

Early Phase 1

Completed

Conditions: Alzheimer's Disease

Interventions: Behavioral: Aerobic Exercise Group 1
Behavioral: Aerobic Exercise Group 3
Behavioral: Nonexercise control group
Behavioral: Aerobic Exercise Group 2

Registration Number: NCT01129115

Lead Sponsor: Jeff Burns, MD

Brief Summary: This is a randomized, 26-week study of supervised exercise assessing three doses of exercise in sedentary individuals 65 years of age and over with age-related cognitive changes. A total of 100 subjects (n=25 in each of four groups) will be randomized to a non-aerobic control group, 75 minutes, 150 minutes, or 225 minutes a week of moderate intensity aerobic exercise spread over 3 to 5 days a week for 26 weeks. These exercise doses represent 50%, 100%, or 150% of the recommended exercise dose. Participants will be directly supervised during all exercise sessions for the first two months after which direct supervision will occur during at least one session a week. This is intended to provide increased flexibility while also maintaining direct contact with the participant to enhance adherence. Aerobic fitness, physical function, and cognition will be assessed at baseline and 26 weeks to examine the dose-response relationships.

Detailed Description: Not available

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 101

Inclusion Criteria

Informed consent
Age 65 years or older
Underactive or sedentary based on the Telephone Assessment of Physical Activity
Community dwelling with a caregiver willing to accompany the participant to visits to the screening evaluation. The caregiver must visit with the subject more than five times a week.
Nondemented: Clinical Dementia Rating (CDR) 0
Adequate visual and auditory abilities to perform all aspects of the cognitive and functional assessments
Stable doses of medications for at least 30 days prior to screening.
Likely to participate in all scheduled evaluations and complete the exercise program over 52 weeks

Exclusion Criteria

Dementia
CDR > 0
Current clinically significant major psychiatric disorder (e.g., Major Depressive Disorder) according to Diagnostic Statistical Manual (DSM)-IV criteria or Geriatric Depression score of 5 or greater.
Significant psychiatric symptoms (e.g., hallucinations) that could impair the completion of the study
Current clinically-significant systemic illness likely to result in deterioration of the patient's condition or affect the patient's safety during the study
History of clinically-evident stroke
Clinically-significant infection within the last 30 days
Myocardial infarction or symptoms of coronary artery disease (e.g., angina) in the last two-years.
Uncontrolled hypertension within the last 6 months
History of cancer within the last 5 years (except non-metastatic basal or squamous cell carcinoma)
History of drug or alcohol abuse as defined by DSM-IV criteria within the last 2 years
Insulin-dependent diabetes mellitus
Significant pain or musculoskeletal disorder that would prohibit participation in an exercise program

Study & Design

Study Type: INTERVENTIONAL

Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Aerobic Exercise Group 1	Aerobic Exercise Group 1	-
Aerobic Exercise Group 3	Aerobic Exercise Group 3	-
Nonexercise control group	Nonexercise control group	-
Aerobic Exercise Group 2	Aerobic Exercise Group 2	-

Primary Outcome Measures

Name	Time	Method
Visuospatial Processing	26 weeks	Visuospatial Processing is a latent derived variable derived estimated mean.The reported latent means for this trial are created from the well-known neuropsychological tests: Block Design, Stroop Color Reading, Digit Symbol Substitution and Trailmaking Test A. Latent variables cannot be measured directly but are derived from a theory-driven confirmatory factor analysis in a structural equation model framework. The latent scores are centered around a mean of 0 and standardized so each value represents a fraction of the standard deviation. There are no limits to the scores. Positive number indicate improved performance. Negative numbers indicate worsening performance.
Change in Maximal Oxygen Consumption	26 weeks	Maximal Oxygen consumption (VO2 max) is the standard, quantitative measure of aerobic fitness. The physiologic range of scores is approximately 3.5 milliliters of oxygen per kilogram of body weight per minute (ml/kg/min) to approximately 90 (ml/kg/min). Higher numbers indicate greater fitness and positive change indicates increasing fitness. Lower number indicate worse fitness
Change in Physical Performance Test	26 Week	The Physical Performance Test is a 9-item measure of physical function. The range of scores is 0-34. Higher numbers indicate better physical function. Positive change indicates improving function. Negative change indicates decreasing function.

Secondary Outcome Measures

Name	Time	Method
Verbal Memory	26 weeks	Verbal Memory is a latent derived variable derived estimated mean. The reported latent means for this trial are created from the well-known neuropsychological tests: Logical Memory, Delayed Logical Memory, Selective Reminding Task - Free Recall Total, Boston Naming Test. Latent variables cannot be measured directly but are derived from a theory-driven confirmatory factor analysis in a structural equation model framework. The latent scores are centered around a mean of 0 and standardized so each value represents a fraction of the standard deviation. There are no limits to the scores. Positive number indicate improved performance.Negative numbers indicate worsening performance.
Simple Attention	26 Weeks	Simple Attention is a latent derived variable derived estimated mean. The reported latent means for this trial are created from the well-known neuropsychological tests: Digit span Forward and Backward, Letter Numbers Sequencing. Latent variables cannot be measured directly but are derived from a theory-driven confirmatory factor analysis in a structural equation model framework. The latent scores are centered around a mean of 0 and standardized so each value represents a fraction of the standard deviation. There are no limits to the scores. Positive number indicate improved performance. Negative numbers indicate worsening performance.
Set Maintenance & Shifting	26 Weeks	Set Maintenance and Switching is a latent derived variable derived estimated mean. The reported latent means for this trial are created from the well-known neuropsychological tests: DKEFS Card Sort, Animal and Vegetable Category Fluency. Latent variables cannot be measured directly but are derived from a theory-driven confirmatory factor analysis in a structural equation model framework. The latent scores are centered around a mean of 0 and standardized so each value represents a fraction of the standard deviation. There are no limits to the scores. Positive number indicate improved performance. Negative numbers indicate worsening performance.
Reasoning	26 Weeks	Reasoning is a latent derived variable derived estimated mean. The reported latent means for this trial are created from the well-known neuropsychological tests:Letter and Word Inductive Reasoning, Matrix Reasoning. Latent variables cannot be measured directly but are derived from a theory-driven confirmatory factor analysis in a structural equation model framework. The latent scores are centered around a mean of 0 and standardized so each value represents a fraction of the standard deviation. There are no limits to the scores. Positive number indicate improved performance. Negative numbers indicate worsening performance.