Myostatin Levels and the Risk of Myopenia and Rheumatoid Cachexia in Women with Rheumatoid Arthritis

The Role of Exercise to Improve Physiological, Physical and Psychological Health Outcome in Idiopathic Inflammatory Myopathies (IIM)

Idiopathic inflammatory myopathies (IIM) impact all aspects of health, physiological, physical, and psychological. Hallmark symptoms of IIM are muscle weakness, reduced muscle endurance and aerobic capacity. Recently, pain and fatigue as well as anxiety and depression have emerged as common and debilitating symptoms in patients with IIM. The aim of this scoping review is to, in a holistic way, describe how IIM impact patients' physiological, physical, and psychological health and how exercise has a role to treat as well as potentially counteract the effects of the disease. Inflammation induces non-immune response and organ damage. These changes with additional impact of physical inactivity lead to muscle impairment and reduced aerobic capacity. Pain, fatigue and low psychological well-being and overall quality of life are also common health aspects of IIM. Medical treatment can reduce inflammation but has in turn serious side effects such as muscle atrophy, type-II diabetes, and hypertension, which exercise has the potential to treat, and perhaps also counteract. In addition, exercise improves muscle function, aerobic capacity and might also reduce fatigue and pain. New evidence shows that reducing systemic inflammation may also improve patient-reported subjective health, quality of life and psychological well-being. Exercise in combination with medical treatment is becoming an important part of the treatment for patients with IIM as exercise has the potential to promote health aspects of various dimensions in patients with IIM.

Rheumatoid sarcopenia: loss of skeletal muscle strength and mass in rheumatoid arthritis

Sarcopenia, a disorder that involves the generalized loss of skeletal muscle strength and mass, was formally recognized as a disease by its inclusion in the International Classification of Diseases in 2016. Sarcopenia typically affects older people, but younger individuals with chronic disease are also at risk. The risk of sarcopenia is high (with a prevalence of ≥25%) in individuals with rheumatoid arthritis (RA), and this rheumatoid sarcopenia is associated with increased likelihood of falls, fractures and physical disability, in addition to the burden of joint inflammation and damage. Chronic inflammation mediated by cytokines such as TNF, IL-6 and IFNγ contributes to aberrant muscle homeostasis (for instance, by exacerbating muscle protein breakdown), and results from transcriptomic studies have identified dysfunction of muscle stem cells and metabolism in RA. Progressive resistance exercise is an effective therapy for rheumatoid sarcopenia but it can be challenging or unsuitable for some individuals. The unmet need for anti-sarcopenia pharmacotherapies is great, both for people with RA and for otherwise healthy older adults.

Risk Factors of Muscle Wasting in Women with Rheumatoid Arthritis: Relevance of the Persistent Failure of Conventional Combination Therapy

Background: Muscle wasting, also known as myopenia, is frequent in rheumatoid arthritis (RA). To date, it is still unknown if the failure of pharmacologic therapies increases the risk of myopenia in RA. Objective: To identify if treatment failure with conventional synthetic DMARDs (csDMARDs) constitutes an independent risk factor of muscle wasting in women with RA. Methods: This was a cross-sectional study. We included 277 women with RA. Assessments in RA patients included: clinical, epidemiological, and therapeutic variables. The skeletal muscle index (SMI) was estimated by DXA, and myopenia was diagnosed if they had an SMI < 5.45 kg/m2. Multivariable logistic regression models identified risk factors of myopenia. Results: Muscle wasting was observed in 28.2% of patients with RA. The risk factors of myopenia in RA were menopausal (OR: 4.45, 95% CI: 1.86 to 10.64) and failure of combined therapy with csDMARDs (OR: 2.42, 95% CI: 1.15 to 5.07). The increased body mass index was protective (OR:0.81, 95% CI: 0.75 to 0.87). Conclusions: Around one of four patients with RA presented muscle wasting. Muscle wasting is related to treatment failure of combined csDMARDs; other factors influencing the presence of muscle wasting is being postmenopausal, whereas, the body mass index was a protective factor.