Background and aims
Rheumatoid arthritis (RA) patients typically experience a significant loss of muscle. This
reduces their ability to complete daily tasks and increases disability, as well as increasing
the risk to infection and other illness.
Exercise is most effective for increasing muscle size and strength, but it is time consuming,
expensive and hard work, meaning uptake is poor. So, widely acceptable alternatives are
required.
The study aims to test a food supplement called creatine. Creatine, often found in meat and
fish, make up an essential part of the systems that provide energy to the muscles for
movement and exercise.
The creatine will be provided as a fruit flavoured powder that participants will mix with
water and drink, much like a fruit squash. In healthy individuals, food supplementation with
creatine (Cr) increases muscle size and improves physical function and quality of life. The
aim of this study is to investigate whether RA patients may benefit similarly
Who are the participants?
50 patients with who have stable and controlled RA, are over age 18, with no known kidney
problems.
What does the study involve?
50 participants will be given a food supplement to take for 12 weeks; this supplement will
either be creatine or a placebo (a regular fruit flavoured powder that has no benefits).
Participants will be randomly allocated to a group and will not be told which supplement they
are taking until the end of the trial. The supplement will be taken as a drink 4 times a day
for the first 5 days, and then once a day for the remainder of the 12 weeks.
Participants will be asked to attend Bangor University 4 times to have a series of tests
done.
The four testing points are:
before they start supplementation
after the 5 days
at completion of the 12-weeks of supplementation
12 weeks after completion of the 12 week supplementation period.
At all four testing points (1-4) body fat and muscle size (body composition), physical
function, and fitness (aerobic capacity of the heart and lungs to transport oxygen to the
exercising muscles) will be tested. In addition, quality of life questionnaires will be
completed, disease activity will be assessed and blood samples will be taken. Muscle samples
(muscle biopsy) will be obtained, from those who volunteer to provide them, at baseline and
post-treatment (test points 1 and 3).
Body fat and muscle size (body composition) will be assessed using type of X-ray called
'dual-entry X-ray absorptiometry' (DXA) scans and by looking at body water levels. DXA allows
the research team to estimate the amount of lean tissue (muscle) and fat that is in the body.
The scan is completely painless.
Physical function will be assessed using the following tests:
strength tests of the knee muscles and hand-grip
the Up-and-Go Test (UG) - For the UG, participants are required rise from a seated
position on a fixed chair, walk forward to a cone placed 8ft (2.44 m) away, and return
to the chair and a seated position.
the sit-to-stand in 30 sec test (SST-30) - For the SST-30 participants will rise from
the same seated position as during the UG as many times as possible in 30 s whilst
keeping their arms folded across the chest.
50-ft walk test - During the 50-ft walk test, time taken to complete the walk along a
straight line marked by cones is recorded
To assess fitness participants will complete a step test. During the test participants
are required to step up and down a 10-inch step at a tempo controlled by a metronome for
three x three-minute stages or until the target heart rate (65% of predicted maximum
heart rate) is achieved. This test will normally last 3 minutes
What are the potential risks and benefits?
Risks - A disadvantage of taking part is the time commitment required to participate in the
study. Whilst taking the supplement drink will be quick and simple, there are 4 testing
sessions which may 2 hours in which participants must attend at Bangor University. Any travel
expenses participants incur for participating in this study will be paid for.
Creatine supplementation will cause some weight gain; in the short-term this is due to water
retention by the muscle and in the long-term this is due to an increase in muscle size.
Previous research, including research with RA patients, has found no adverse side effects
that can be linked to the creatine supplementation. There are anecdotal reports of creatine
supplementation causing muscle cramps, stomach and heart problems; however no evidence has
ever linked these directly to the creatine itself.
There is also a slight possibility that the muscle biopsy site (where the muscle is taken)
could bruise and be sore but this is quite rare and in fact most people report only a short
term slight ache after the biopsy.
There is also an exposure to radiation (emission of energy) from the DXA scan, though this is
only a small amount. However, because of this radiation pregnant women are not allowed to
part in the study.
Benefits - Taking creatine supplements will increase muscle strength and improve physical
function and quality of life.
Participants will receive creatine supplementation regardless of which group they are
initially put into. Participants will also be informed about their fitness levels and will
receive advice on how to improve these.
The standard DXA can inform the investigaters of a disease in the bone that can increase the
risk of fractures (osteoporosis) that patients might not know they had.
Who is running the study and how long will it last? The study will commence in January 2012
and is being undertaken by the School of Sport, Health and Exericse Sciences (SSHES) at
Bangor University, Wales, in association with the Rheumatology department at Ysbyty Gwynedd
Hospital, Bangor.
Who is funding the study? The study is being funded by Betsi Cadwalader University Health
Board. The study is expected to finish within an 18 month time frame, with recruiting open
for a year or until 50 patients have been found.
Who is the main contact? Prof Andrew Lemmey a.lemmey@bangor.ac.uk Dr Tom O'Brien
thomas.obrien@bangor.ac.uk Thomas Wilkinson, thomas.wilkinson@bangor.ac.uk
