Research objectives:
To evaluate the effects of 26 weeks of creatine supplementation on its own and in
combination with progressive resistance training in community-dwelling older adults with
mild cognitive impairment on:
visuospatial working memory (Primary Objective);
executive function (working memory, inhibitory control, and mental flexibility),
functional mobility, muscle and grip strength, bone density, cerebral blood flow,
and blood-based biomarkers for brain health and cognitive decline (Secondary
Objectives); and
resting state functional activity, hippocampal volume and structural integrity, and
key metabolite concentrations in the brain (Exploratory Objective).
Hypotheses:
It is hypothesized that 26 weeks of creatine supplementation and resistance training in
community-dwelling older adults with mild cognitive impairment will: 1) increase
visuospatial working memory performance; 2) improve executive function, functional
mobility, strength performance, bone density, cerebral blood flow, and blood-based
biomarkers for brain health and cognitive decline; and 3) increase resting state
functional activity, volume and structural integrity in the hippocampus, and
concentrations of key metabolites in the brain.
Methods:
Screening: Participants interested in the study will reach out to researchers via phone
or e-mail. Interested participants will be sent the Letter of Information via e-mail to
get more detailed information about the study. Before a baseline assessment is scheduled,
investigators will complete an initial screening over the phone with all participants to
ensure that study eligibility is met. The Physical Activity Readiness Questionnaire
(PAR-Q) will be administered over the phone as part of initial screening to ensure that
they can partake in exercise. At this time, participants will have an opportunity to ask
questions. Those who are eligible and still interested in participating will be scheduled
to come into the lab for baseline assessments.
Baseline assessments: When participants arrive in the lab, the researcher will go over
the consent form with them, answer any additional questions they have about the study,
and obtain informed written consent. At this time, participants may also consent to
participate in the optional MRI portion of this study. Participants will then complete
baseline assessments. Total time to complete baseline assessments in the lab (excluding
MRI) will be ~2.5-3 hours. For those participating in the MRI component, this will be
scheduled for another separate visit (1 hour).
Randomization: Once participants complete baseline assessment, they will be randomly
assigned to one of the four conditions. Group allocation will be determined by an online
randomizer (randomization.com). The sequence will be held remotely by the PI and will not
be revealed until after baseline assessments.
Descriptors and covariates:
Anthropometry (height, weight)
Demographic information via general questionnaire (e.g., age, sex, gender,
ethnicity, education, socioeconomic status)
Global cognitive function (Montreal Cognitive Assessment, MoCA; Mini-Mental Status
Examination, MMSE). MoCA is used as a screening tool for mild cognitive impairment.
This test assesses cognitive ability in the domains of attention and concentration,
executive functions, memory, language, visuo-constructional skills, conceptual
thinking, calculations, and orientation. Maximum score is 30. The MMSE is used as a
screening tool for cognitive impairment. This 11-item test assesses global cognitive
function in the domains of orientation, registration, attention and calculation,
recall, and language. Maximum score is 30.
Physical activity levels (Physical Activities Scale for the Elderly, PASE). Used to
measure the level of self-reported physical activity, and consists of 12 questions
about leisure, household, and work-related daily activity.
Mood (Depression Scale, GDS).The GDS is a 15-item questionnaire used to test for the
presence of depression. If depression is suspected, the PI will ensure that the
participant is provided with a copy of the questionnaire and will advise the
participant to make an appointment with their family physician to discuss the
results.
Number of co-morbidities (Functional Comorbidity Index, FCI). The FCI is an 18-item
list of diagnoses used to determine co-morbidities.
Health-related quality of life (Short Form Health Survey, SF-36). A self-report
measure examining eight domains: vitality, physical functioning, bodily pain,
general health perceptions, physical role functioning, emotional role functioning,
social role functioning, and mental health. Scores range from 0-100, with higher
scores indicating greater health status and quality of life.
Loneliness (UCLA, Loneliness Scale). A 20-item self report measure on loneliness and
interpersonal problems.
Adherence: All participants will be asked to record their supplement consumption on a
calendar, which will be returned to the lab weekly. Exercise class attendance will be
recorded each session by instructors. Participants will be encouraged to adhere to both
the supplement protocol and exercise classes. The investigators will implement the
following strategies to promote participant engagement:
Semi-monthly newsletters that will feature personal accomplishments of participants
(with permission) and study updates, for example.
Investigators will follow up with participants who have missed supplement doses or
exercise sessions to discuss barriers and strategies to overcome them on an
individual basis.
If participants miss classes due to illness/travel, they will be scheduled to make up
missing classes as soon as possible. If participants miss classes without notifying
investigators in advance, investigators will call to remind them about their classes and
encourage increased compliance.
During the 26-week intervention, participants will also complete the following
assessments:
PASE (described in baseline assessments) - This will be used to monitor exercise
outside of the program and will be administered at the last exercise session of each
month.
Falls - Because declines in mobility are known to co-occur with declines in
cognition, the investigators will monitor falls throughout the study duration to
further characterize our sample. Participants will be asked to note falls in their
calendar if they occur, which as mentioned above will be returned to the lab weekly
for review by instructors.
Dietary intake - A three day weighed food record will be used to assess nutrient and
energy intake at baseline and endpoint. Participants will record their dietary
consumption over three days per month (two weekday and one weekend day). They will
be instructed on how to do the food record at the first exercise session and will be
asked to return it by the last exercise session of that month. The endpoint food
record will be given to participants at the first session of the last month of the
intervention and they will be asked to return it by the last exercise session of the
month. A dietetic student will assist in analyzing this data.
Real-time physical activity levels will be monitored using wearable accelerometers
(ActiGraph ambulatory monitoring wearables). Participants will be given the
accelerometer to wear on their wrist for at baseline (one week during the first
month of the intervention) and endpoint (one week during the last month of the
intervention). This will allow objective quantification of energy expenditure,
metabolic equivalent of task rates, steps, physical activity intensity, sedentary
bouts, and sleep latency. They are Bluetooth enabled for real-time data uploads and
include a wear-time sensor to assess compliance.
Final assessment: All baseline assessments will be completed at endpoint (26 weeks). The
sub-set of participants at baseline who underwent MRI will also undergo the MRI protocol
at endpoint.
Data analysis: Behavioural data (cognitive assessments, mobility, and physical measures)
will be analyzed in SPSS. Primary and secondary outcome measures will be examined using a
two-way ANCOVA to examine main effects of creatine supplementation and resistance
training as well as the interaction between the two factors. The investigators will use
the intention to treat principle where all randomized participants will be included in
the final analysis regardless of adherence to the intervention. MRI data will be analyzed
in Freesurfer and FSL. MRI/MRS data will be analyzed in collaboration with an expert who
is familiar with processing this data. Investigators will examine changes over the
intervention and compare these changes between groups.
Significance of research: This research is the first to address a critical gap in the
literature by examining the effects of creatine and resistance training alone and in
conjunction on various measures of physical function, cognitive function, and brain
health in older adults with MCI. In the context of an aging population and given the
overall safety and accessibility of creatine and resistance training, the findings from
our study may inform biomarker-driven, non-pharmalogical strategies and interventions to
offset or defer further cognitive decline in older adults with MCI.