Sarcopenia and Juvenile Idiopathic Arthritis

To be part of this study, you need to be between 15 and 40 years old and have been diagnosed with Juvenile Idiopathic Arthritis (JIA). You must be receiving care at one of the participating hospitals in France and be covered by the French social security system (which handles healthcare costs). Most importantly, you and, if you are under 18, your parents or legal guardians, must agree to take part and sign a consent form.

There are some reasons why someone might not be able to join. For example, if you are under legal guardianship, not covered by social security, are pregnant, or if you wouldn't be able to do some of the simple tests required, like the handgrip strength test or the special body scan (DEXA). Also, if you find it difficult to understand questionnaires, you might not be suitable for this study.

If you decide to take part in this study, you'll have a special assessment during one of your regular rheumatology appointments. First, you'll get detailed information about the study, and if you agree, you'll sign a consent form (if you're under 18, your parents or guardians will too). During this single visit, you will have your handgrip strength measured using a special device. You'll also have a body scan called a DEXA to check your muscle and fat levels. Finally, you'll fill out some questionnaires about your diet, how tired you feel, how active you are, and how your JIA affects your daily life. The study will also collect some information from your medical records, like your JIA history and treatments. These assessments are all part of a single visit and there's no medication involved or long-term follow-up specifically for the study. If the study identifies sarcopenia, your doctor might suggest additional care as part of your usual treatment.