Clinical Trial Details
— Status: Active, not recruiting
Administrative data
NCT number |
NCT02614365 |
Other study ID # |
07-MED-41E |
Secondary ID |
|
Status |
Active, not recruiting |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
July 2014 |
Est. completion date |
December 2022 |
Study information
Verified date |
March 2021 |
Source |
Howard University |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
Whereas the advantageous effects of exercise-training on memory is increasingly recognized,
the practicality and clinical usefulness of such interventions in community-dwelling older
African Americans (AA)s Mild Cognitively Impaired (MCI) subjects, and the mechanism by which
an effect occurs need elucidation. Because aerobic-exercise can improve emerging
cardiovascular (CVD)-related risk factors for cognitive decline such as lipids, inflammatory
cytokines and glucose homeostasis; the Investigators will examine training effects on these
and related biomarkers. The imperative for this study is further underscored by the fact
that, AAs: i) have high rates of dementia, and ii) have paucity of cross-sectional, and lack
prospective data on the effects of exercise on cognition. To overcome barriers to recruitment
and retention, enhance compliance with a long exercise program (3-times/week), and maximize
the use of available resources, the Investigators will use a community-based approach.
Therefore, the primary objectives of this study build on the Investigators' experience, and
will compare the effects of aerobic-exercise to stretch-exercise (control) in
community-dwelling AA MCI subjects. Following the initial 6 months active intervention, the
aerobic-exercise group will follow a prescribed but free living 40 minutes, 3 time/week
exercise regimen while the control group returns to usual care plus stretch-exercise for
additional 12 months. This study will facilitate the estimation of sample size for a larger
confirmatory study in AAs. A newly acquired direct oversight of the DC Ward-6 Senior Wellness
Center and its infrastructures by the Howard University Division of Geriatrics will provide
additional resources and access to the community. In addition to the Investigator's
feasibility aims, the Investigators will determine performance on cognitive tasks using the
Alzheimer's Disease Assessment Scale-Cognitive Sub-scale (ADAS-Cog) and Clinical Dementia
Rating Scale (CDR) sum of boxes supplemented by tests of executive function (EF) and
Functional Activity Questionnaire (FA) and together as ADAS-Cog-Plus; changes in brain volume
regions of interest (ROI) with Magnetic Resonance Imaging (MRI), selected CVD and AD-related
bio-markers.
Description:
Although anticholinesterase therapies have greatly improved the symptomatic treatment of
Alzheimer's disease (AD), they have not been demonstrated to significantly slow the disease
progression; and amyloid-directed therapies have produced disappointing results. A promising
evidence-based and relatively side-effect free lifestyle approach is emerging as an
alternative or adjunct to drug therapy. In cross-section and prospective studies, and a few
randomized controlled trials; aerobic exercise-training has been demonstrated to improve
cognition in older subjects. However, the mechanisms of these effects remain poorly
understood. Because it is now recognized that cardiovascular disease (CVD) risks can catalyze
AD development, it is vital to test whether lifestyle adaptation shown to reduce CVD risks
can favorably modify cognitive trajectories and markers of neurodegeneration. Such
interventions may benefit those at an early and clinically discernible prodromal stage of AD
such as mild cognitive impairment (MCI). Notably, such data are currently lacking in African
Americans (AA)s who harbor higher rate of CVD risks and AD.
While a laboratory approach to exercise intervention study is required to prove causation,
such a design may not lend itself to real-life application, and is demanding for many
economically and educationally disadvantaged older AAs experiencing early symptoms of
cognitive deterioration. To address this concern, the Investigators seek to initiate an
18-month study, testing real-life applicability of the effects of exercise adaptation on
memory in a more ideal community setting. However, those who chose to exercise at an academic
center will not be excluded. Collection of outcome measures at baseline, 3-month, 6-month,
9-month, 12-month and 18-month will provide pilot data to inform dose and duration effects of
exercise on outcome measures. In addition to augmenting enrollments, the proposed approach
will bolster retention.
The objectives of this pilot study, therefore, are to examine the feasibility of a
community-based 18-month study (6-month active intervention and 12-month passive follow-up)
aerobic exercise-training on neurodegeneration in AAs MCI subjects. The Investigators will
test the hypotheses by randomizing subjects into one of 2 groups: 1.) aerobic-exercise; and
2.) stretch-exercise (control). The Investigators proposed that the aerobic-exercise group
will perform better than control group on cognitive measures. Secondarily, the Investigators
will determine whether training-induced changes in cognition relate to increases in brain
volume. Exploratory, the Investigators will also investigate intervention effects on
cerebrospinal fluid (CSF) biomarkers, selected CVD risk factors and biomarkers, cerebral
oxygenation and Hypoxia-Inducible Factors (HIF-1α) gene expression, and Apolipoprotein E gene
(APOE), to assess their mediation of training-induced changes in cognition.
A team of experienced Investigators in neuroimaging, neurology, cognitive neuroscience, and
exercise physiology has been assembled to conduct this study. Working collaboratively with
the District of Columbia Office on Aging (DCOA), the Directors of the Ward 6 Senior Wellness
Center operated by DCOA, and the lead agencies on aging (community grassroots organizations
supported by DCOA), the Investigators will recruit, enroll, randomize, and train participants
at the wellness center. After obtaining informed consent and completing an initial
assessment, participants will undergo initial exercise screening to determine their ability
to exercise safely. Following randomization of 80 volunteers into aerobic-exercise (40) and
control (40); baseline neuropsychological, neuroimaging and biomarker measurements will be
obtained. Both groups will undergo 3 times/week supervised group-specific intervention at the
wellness center for 6 months. After the initial 6 months of active intervention, the
aerobic-exercise group will follow a prescribed but free living 40 minutes, 3 time/week
exercise regimen, while the control group returns to usual care. Baseline tests will be
repeated at 3 month, after 6 months (active intervention period); and at 9, 12 and 18 months
(passive follow-up period). Treadmill, lumber puncture (LP) and brain magnetic resonance
imaging (MRI) tests will occur only at baseline and 6 months. Between groups changes in
cognitive performance, biomarkers, and neuroimaging measurements will be compared using
appropriate multivariate methods.
While the Investigators remain cognizant of other planned or ongoing fitness and memory
trial, the proposed study is unique in the sense that: it is a logical extension of the
Investigators' ongoing work; tests the proposed hypotheses in predominantly AA sample in whom
paucity of data remains, and therefore, will advance reduction in health disparity; will
obtain data at multiple time-points (baseline, 3, 6, 9, 12 and 18 months) and therefore allow
for the assessments of the effects of duration and dose of intervention on outcome measures;
test the real-life applicability of the proposed intervention in a community setting; and
generate pilot data on the mechanisms by which these interventions affects memory.
Importantly, outcomes from this study may lead to practical and effective strategy to delay
cognitive decline in populations at most risk, and can prevent or attenuate the physical,
psychological and the economic burden associated with dementia in AAs.