The Effect of Creatine Supplementation on Muscle Function in Childhood Myositis

Study Overview
=================
Brief Summary
-----------------
This project will bring together a multidisciplinary team of pediatric rheumatologists, neurologists, metabolic geneticists and exercise physiologists to determine the effect of creatine (CR) supplementation on muscle function and muscle metabolism in children with Dermatomyositis (DM). The investigators propose using well-established exercise testing techniques as well as new, powerful exercise imaging protocols in order to better delineate the effects of CR on muscle pathophysiology in a non-invasive way. Evidence from this study will provide information regarding the effect of creatine supplementation on muscle function in DM. Improvements in muscle function and fatigue through CR use may also contribute to an improvement in quality of life and have significant clinical implications for the treatment of children with DM.

Official Title
-----------------
The Effect of Creatine Supplementation on Muscle Function in Childhood Myositis

Conditions
-----------------
Juvenile Dermatomyositis

Intervention / Treatment
-----------------
* Dietary Supplement: Creapure
* Dietary Supplement: Glucose Tablet


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Ages 7 to 18 years Diagnosis of probable JDM (onset <16 years) according to Bohan and Peter criteria Subjects on a stable course of medication (unlikely to change over study treatment period as determined by the treating physician) Minimum height of 132.5cm Exclusion Criteria: Subjects newly diagnosed with JDM within the previous 6 months Subjects unable to cooperate with study procedures, or too weak to participate in the exercise testing Subjects with impaired kidney function as determined from baseline visit screening lab values Subjects who are currently pregnant or planning to become pregnant within the study period Subjects who are shorter than 132.5cm

Ages Eligible for Study
-----------------
Minimum Age: 7 Years
Maximum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Treatment<br>patients on this arm will be treated with creapure supplements | Dietary Supplement: Creapure<br>* Patients will be prescribed a creapure supplement by weight, to be taken 3x/day for the duration of the trial. They will be randomized to an active product start time using a multiple baseline design.<br>* Other names: ultrapure creatine monohydrate;|
| Placebo Comparator: Placebo<br>patients on this arm will be given a placebo glucose tablet supplement | Dietary Supplement: Glucose Tablet<br>* Patients will be prescribed the placebo supplement by weight, to be taken 3x/day for the duration of the trial. They will be randomized to an active product start time using a multiple baseline design.<br>* Other names: Placebo;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Muscle function | Will be determined by mean power output using a Wingate cycle ergometer protocol | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Muscle metabolism | The effects of creatine supplementation on key metabolites responsible for proper energy shuttling in healthy muscle will be measured at rest and using exercise protocols in subjects with P-MRS. | 6 months | 
| Quality of life | Both overall and health-related quality of life will be measured at each study visit with the Quality of My Life scale. | 6 months | 
| Disease Activity | Will be measured using the International Myositis Assessment and Clinical Studies Group (IMACS) before and after creatine supplementation | 6 months | 
| Muscle Strength | Will be estimated at each study visit from a maximal jump test and hand grip strength. | 6 months | 
| Fatigue | Will be determined using the PedsQL fatigue module which has been validated for use in children with fibromyalgia and rheumatic disease. | 6 months | 
| Adherence | This will be assessed based on a positive blood plasma and urine tests for creatine use over the course of the study period, amount of medication remaining and through self-reports using study diaries. | 6 months |