Sarcopenia in Rheumatoid arthritis. A narrative review

Prevalence and Associated Factors of Sarcopenia in Thai Rheumatoid Arthritis Patients: A Cross-Sectional Study

BACKGROUND/OBJECTIVES

Sarcopenia associates with poor health-related quality of life (HRQoL). This study aimed to determine prevalence and factors associated with sarcopenia in rheumatoid arthritis (RA) patients. The HRQoL between RA patients with and without sarcopenia also was compared.

METHODS

This cross-sectional study recruited RA patients, aged ≥20 years, at Chiang Mai University Hospital between May and November 2023. Their skeletal muscle mass (bioelectrical impedance analysis), grip strength (hand dynamometer), and physical performance (gait speed test) were evaluated. Sarcopenia was defined according to the Asian Working Group for Sarcopenia. Patient characteristics, disease activity, physical disability (HAQ-DI), HRQoL (SF-36), nutrition (mini nutrition assessment), and medications were recorded.

RESULTS

Of 299 patients (89.0% female; age 61.3 ± 11.6 years; disease duration 13.9 ± 8.6 years), 37.5% had sarcopenia (27.4% severe sarcopenia). In multivariable analysis, body mass index (odds ratio [95% confidence interval] 1.46/1 unit decrease [1.27, 1.68], p < 0.001), disease duration (1.89/10 years increase [1.27, 2.83], p = 0.002), deformity of hands/feet (3.80 [1.50, 9.61], p = 0.005), mini nutritional assessment score (1.21/1 score decrease [1.04, 1.40], p = 0.012), and high C-reactive protein (CRP) (1.94 [1.02, 3.69], p = 0.044) were independent factors associated with sarcopenia. There was no relationship between sarcopenia and disease activity (DAS-28-ESR or CRP) or medication use. RA patients with sarcopenia had higher HAQ score than those without, but potentially lower scores in physical function domain of SF-36 with adjusted mean difference of 0.2 (95% confidence interval 0.03, 0.32, p = 0.022) and -5.9 (-12.24, 0.38, p = 0.066), respectively.

CONCLUSIONS

About one third of the Thai RA patients in this center had sarcopenia. Low body mass index, long disease duration, joint deformity, malnutrition, and high CRP were independent factors associated with sarcopenia. Sarcopenia affects physical capabilities and the physical function domain of the HRQoL.

What have we learnt from the inhibition of IL-6 in RA and what are the clinical opportunities for patient outcomes?

Rheumatoid arthritis (RA) is an autoimmune disease characterised by persistent inflammation of the synovial joints as well as other tissues and organs. Left untreated, it can lead to joint damage, disability and even increased mortality. The disease is driven by inflammatory cytokines that contribute to the chronic inflammation seen in RA. Interleukin-6 (IL-6) is a key pathological cytokine and a target for treatments aiming to alleviate local and systemic inflammation. Despite advances in understanding RA and the introduction of new treatments, achieving sustained remission remains challenging. This review explores the role of IL-6 in RA pathogenesis, its potential as a treatment target and the significance of personalised medicine in RA management. IL-6 has a dual signalling mechanism, classical and trans-signalling, which influences various intracellular pathways. While several targeted therapies have emerged, no single mechanism-based therapy is universally effective due to the diversity and complexity of the disease. Different approaches to targeting IL-6 have been tested, including biologic blockade of receptors or ligands, and inhibition of IL-6 signalling. IL-6 receptor inhibitors have been validated as RA therapeutics, either alone or in combination with other treatments. Tocilizumab, the first approved IL-6 inhibitor, blocks both soluble and membrane-bound IL-6 receptors, reducing the inflammatory cascade. Clinical trials confirm the efficacy and safety of tocilizumab and its role as a treatment option for patients unresponsive to conventional therapies. The benefits of IL-6 inhibition extend beyond reduced joint inflammation to the amelioration of comorbidities like anaemia, cardiovascular disease, depression and osteoporosis. Tailoring treatment to patients' profiles and comorbidities is essential for optimal outcomes. A 'treat-to-profile' approach, focusing on a holistic view of the patient, could improve personalised medicine strategies. Biosimilars - lower-cost alternatives to biologics - further enhance the accessibility and cost-effectiveness of treatment. IL-6 inhibitors present a valuable treatment option for RA management, particularly for patients with specific comorbidities.

Rodent model intervention for prevention and optimal management of sarcopenia: A systematic review on the beneficial effects of nutrients & non-nutrients and exercise to improve skeletal muscle health

Sarcopenia is a common musculoskeletal disorder characterized by degenerative processes and is strongly linked to an increased susceptibility to falls, fractures, physical limitations, and mortality. Several models have been used to explore therapeutic and preventative measures as well as to gain insight into the molecular mechanisms behind sarcopenia. With novel experimental methodologies emerging to design foods or novel versions of conventional foods, understanding the impact of nutrition on the prevention and management of sarcopenia has become important. This review provides a thorough assessment of the use of rodent models of sarcopenia for understanding the aging process, focusing the effects of nutrients, plant extracts, exercise, and combined interventions on skeletal muscle health. According to empirical research, nutraceuticals and functional foods have demonstrated potential benefits in enhancing physical performance. In preclinical investigations, the administration of herbal extracts and naturally occurring bioactive compounds yielded advantageous outcomes such as augmented muscle mass and strength generation. Furthermore, herbal treatments exhibited inhibitory effects on muscle atrophy and sarcopenia. A substantial body of information establishes a connection between diet and the muscle mass, strength, and functionality of older individuals. This suggests that nutrition has a major impact in both the prevention and treatment of sarcopenia.

Comparative Efficacy of Various Exercise Therapies and Combined Treatments on Inflammatory Biomarkers and Morphological Measures of Skeletal Muscle among Older Adults with Knee Osteoarthritis: A Network Meta-Analysis

Osteoarthritis is associated with high risks of sarcopenia in older populations. Exercise interventions are promising treatments for musculoskeletal impairments in knee osteoarthritis (KOA). The purpose of this study was to identify the comparative effects of exercise monotherapy and its adjunct treatments on muscle volume and serum inflammation for older individuals with KOA. A literature search in the electronic databases was comprehensively performed from this study's inception until April 2024 to identify relevant randomized controlled trials (RCTs) that reported muscle morphology and inflammation outcomes after exercise. The included RCTs were analyzed through a frequentist network meta-analysis (NMA). The standard mean difference (SMD) with a 95% confidence interval was estimated for treatment effects on muscle morphology and inflammation biomarkers. The relative effects on each main outcome among all treatment arms were compared using surface under the cumulative ranking (SUCRA) scores. The certainty of evidence (CoE) was assessed by the GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) ranking system. Probable moderators of the treatment efficacy were investigated by network meta-regression analysis. This study included 52 RCTs (4255 patients) for NMA. Among the 27 identified treatment arms, isokinetic training plus physical modality as well as low-load resistance training plus blood-flow restriction yielded the most optimal treatment for inflammation reduction (-1.89; SUCRA = 0.97; CoE = high) and muscle hypertrophy (SMD = 1.28; SUCRA = 0.94; CoE = high). The patient's age (β = -0.73), the intervention time (β = -0.45), and the follow-up duration (β = -0.47) were identified as significant determinants of treatment efficacy on muscle hypertrophy. Exercise therapy in combination with noninvasive agents exert additional effects on inflammation reduction and muscle hypertrophy compared to its corresponding monotherapies for the KOA population. However, such treatment efficacy is likely moderated by the patient's age, the intervention time, and the follow-up duration.

Physical activity assessment in rheumatoid arthritis: a 120-patient cross-sectional study

INTRODUCTION

Rheumatoid arthritis (RA) is a chronic inflammatory disease frequently associated with comorbidities such as cardiovascular diseases. RA patients are more prone to physical inactivity than the general population.

AIM

Our study aimed to evaluate physical activity (PA) in patients with RA and to assess barriers that influence it in RA characteristics.

METHODS

This was a cross sectional study of 120 RA patients. Comorbidities, patients' characteristics, disease activity, function assessed by Health Assessment Questionnaire (HAQ), severity parameters, and extra-articular manifestations were assessed. PA was evaluated with the Short form of the International Physical Activity Questionnaire (IPAQ-S). Factors influencing PA were analyzed.

RESULTS

Mean age was 56.1±10.1 years and sex-ratio was 0.14. Screening for comorbidities showed that 30.7% of patients had hypertension, 18.4% had diabetes, and 71.1% were obese or overweight. Moderate to high disease activity was found in 55.6% of patients. Mean HAQ was 0.9±0.6. Evaluation of PA revealed that mean continuous IPAQ-S was 4226.02±4703 MET-min per week [0-24276]. Physical activity level (categorical IPAQ-S) was low in 24.2% of patients, moderate in 30.8%, and high in 45%. Continuous IPAQ-S was negatively correlated with age (r=-0.18,p=0.045), age of disease onset (r=-0.18,p=0.049), and HAQ (r=-0.25,p=0.01). Besides, categorical IPAQ-S was significantly associated with the presence of hypertension (p=0.03) and gout (p=0.02). Concerning RA parameters, categorical IPAQ-S was significantly associated with HAQ (p=0.03).

CONCLUSION

Our study showed that PA in RA patients can provide significant improvement in terms of quality of life and function. In RA, regular PA should be part of disease management.

Sarcopenia Prevalence and Risk Factors Among Older Adults in Bangkok, Thailand: A Cross-Sectional Study

OBJECTIVES

This study aimed to investigate the prevalence of sarcopenia among older Thai adults residing in Bangkok and identify associated risk factors.

METHODS

This cross-sectional study included Thai adults aged ≥60 years. All participants underwent assessments using the Yubi-wakka test, anthropometric measurements, bioelectrical impedance analysis, handgrip strength tests, and physical performance evaluations. Information on demographic characteristics, chronic health conditions, nutritional status, and medication use was also collected. Sarcopenia was diagnosed according to the 2019 Asian Working Group for Sarcopenia criteria. Statistical analyses were performed using the independent t-test, Chi-square test, and logistic regression to identify risk factors.

RESULTS

Among the 600 participants, the overall prevalence of sarcopenia was 19%. The multivariate analysis identified 13 significant risk factors associated with sarcopenia, including age ≥75 years (odds ratio [OR]=10.6, 95% confidence interval [CI]=3.7-30.2), higher education level (year) (OR=0.85, 95% CI=0.74-0.98), lower income level (OR=5.4, 95% CI=1.4-21.4), Barthel index <90 (OR=11.0, 95% CI=3.5-34.5), lower body mass index (OR=0.7, 95% CI=0.6-0.8), low calf circumference (OR=7.6, 95% CI=2.5-23.3), fall in the past year (OR, 3.1; 95% CI, 1.4-6.6), frailty (OR, 2.3; 95% CI, 1.1-4.5), malnutrition (OR=3.5, 95% CI=1.3-9.3), history of stroke (OR=7.5, 95% CI=1.3-41.4), vitamin D deficiency (OR=9.4, 95% CI=1.1-82.5), knee osteoarthritis (OR=6.3, 95% CI=1.57-25.31), and malignancy (OR=4.8, 95% CI=1.01-22.70).

CONCLUSION

This study evaluated the sarcopenia status across a diverse demographic of older Thai adults using comprehensive assessments, and examined the impact of socioeconomic factors and various chronic conditions on the occurrence of sarcopenia.

Examining the presence of sarcopenia in women with rheumatoid arthritis: Case-control study

INTRODUCTION

The aim of this study was to compare the frequency of sarcopenia, functional status, fear-avoidance behaviors, biopsychosocial status and quality of life in RA women with healthy controls.

METHODS

25 RA women and 25 healthy women were included in the study. Definition of sarcopenia was assessed using parameters recommended by the European Working Group on Sarcopenia (EWGSOP): Bioimpedance analysis for muscle mass (body fat ratio, skeletal muscle mass, skeletal muscle mass index); grip and knee extension strength for muscle strength and 4-m course gait speed test for physical performance was applied. Functional status was evaluated with the Health Assessment Questionnaire (HAQ), fear-avoidance behaviors with the Tampa Kinesiophobia Scale (TKS), biopsychosocial status with the Biopsychosocial Questionnaire (BETY-BQ), and quality of life with Short Form-36 (SF-36).

RESULTS

While none of the healthy women had sarcopenia, severe sarcopenia was detected in 7 (28%) of the women with RA. When RA and healthy groups were compared; skeletal muscle mass (p: 0,004); skeletal muscle mass index (p: 0,011); grip strength-right (p:0.001) and left (p:0.001); knee extension strength-right (p:0.001) and left (p:0.001), 4-m course gait speed test (p:0.001), HAQ (p:0.001), TKS (p:0.001), BETY-BQ (p:0.001), SF-36 physical (p:0.001) ve mental component (p:0.001) results were significant in favor of the healthy group while there was no difference in body fat ratio (p>0.05).

CONCLUSION

In women with RA, the frequency of sarcopenia is higher, and functional status, fear-avoidance behaviors, biopsychosocial status and quality of life are worse than healthy.

Role of Myostatin in Rheumatoid Arthritis: A Review of the Clinical Impact

Rheumatoid arthritis (RA) is a chronic inflammatory disease that affects synovial joints and that frequently involves extra-articular organs. A multiplicity of interleukins (IL) participates in the pathogenesis of RA, including IL-6, IL-1β, transforming growth factor-beta (TGF-β), and tumor necrosis factor (TNF)-α; immune cells such as monocytes, T and B lymphocytes, and macrophages; and auto-antibodies, mainly rheumatoid factor and anti-citrullinated protein antibodies (ACPAs). Skeletal muscle is also involved in RA, with many patients developing muscle wasting and sarcopenia. Several mechanisms are involved in the myopenia observed in RA, and one of them includes the effects of some interleukins and myokines on myocytes. Myostatin is a myokine member of the TGF-β superfamily; the overproduction of myostatin acts as a negative regulator of growth and differentiates the muscle fibers, limiting their number and size. Recent studies have identified abnormalities in the serum myostatin levels of RA patients, and these have been found to be associated with muscle wasting and other manifestations of severe RA. This review analyzes recent information regarding the relationship between myostatin levels and clinical manifestations of RA and the relevance of myostatin as a therapeutic target for future research.

Increased serum adipokines are associated with sarcopenia in non-obese women with rheumatoid arthritis

Large cohort studies have disclosed the association between obesity and rheumatoid arthritis (RA) risk. The sarcopenia prevalence in RA patients can be up to 31%. However, there is little information linking adipokines to sarcopenia in RA, so this study aimed to investigate whether adipokines were indeed involved in secondary sarcopenia in RA with a focus on non-obese females. Sixty-four female patients and 36 controls were included in this study. The serum adipokine levels (leptin and adiponectin) were determined by ELISA kits. The impacts of adipokines on muscle atrophy and potential autophagy were examined in mouse myoblasts, C2C12, upon treatment with recombinant leptin and adiponectin agonist (AdipoRan). Interestingly, serum adiponectin was significantly increased but the ratio of leptin/adiponectin was dramatically decreased in the RA patients with sarcopenia. After normalization by body mass, serum leptin was positively associated but adiponectin was negatively associated with muscle mass respectively, even after adjustment for fat mass. Treating C2C12 cells with leptin and AdipoRan inhibited proliferation of mature myotube respectively, as did treatment with the serum from RA patients. A combination of low leptin and high AdipoRan greatly decreased myogenin, but instead increased MAFbx and MuRF-1 as well as increased Beclin 1, Atg5, and LC3β. Taken together, our study reveals that secondary sarcopenia of RA females may be an imbalance of RA-related, but not obesity-related, increase in adipokine production; additionally, the reduced leptin/adiponectin ratio could be a better indicator in monitoring sarcopenia in non-obese RA females. Moreover, adipokine imbalance may promote muscle atrophy through inducing autophagy.

Geriatric nutrition risk index: a more powerful index identifying muscle mass loss in patients with rheumatoid arthritis

OBJECTIVE

To explore the association of geriatric nutrition risk index (GNRI), a traditional albumin-body weight calculation, with myopenia in patients with rheumatoid arthritis (RA) and compare its ability to identify myopenia with protein indicators.

METHODS

This cross-sectional study was carried out based on a Chinese RA cohort. Clinical data and protein indicators (including albumin, globulin, albumin to globulin ratio, prealbumin, hemoglobin) were collected. GNRI was estimated by serum albumin and body weight. Myopenia was indicated as muscle mass loss measured by bioelectric impedance analysis.

RESULTS

There were 789 RA patients included with mean age 52.6 ± 12.6 years and 77.6% female. There were 41.3%, 18.0%, 27.5%, 13.2% patients with no (GNRI > 98), low (GNRI 92 to ≤ 98), moderate (GNRI 82 to < 92), and major nutrition-related risk (GNRI < 82). There were 406 (51.5%) RA patients with myopenia, RA patients with major nutrition-related risk had the highest prevalence of myopenia (87.5% vs. 73.3% vs. 50.0% vs. 26.1%). Multivariate logistic analysis showed that compared with no risk, RA patients with low (OR = 3.23, 95% CI: 1.86-5.61), moderate (OR = 9.56, 95% CI: 5.70-16.01), and major nutrition-related risk (OR = 28.91, 95% CI: 13.54-61.71) were associated with higher prevalence of myopenia. Receiver operating characteristic curves showed that GNRI (AUC = 0.79) performed a better identifiable ability toward myopenia than serum albumin (AUC = 0.66) or others indicators (AUC range 0.59 to 0.65), respectively.

CONCLUSION

GNRI, an objective and convenient albumin-weight index, may be preferable for identifying myopenia in RA patients. Key Points • We firstly elucidated the association of GNRI with muscle mass loss among RA patients, and compared its ability to identify muscle mass loss with serum albumin or other protein indicators. • Major nutrition-related risk identified by GNRI showed the highest risk of muscle mass loss, GNRI demonstrated a greater ability to identify myopenia in RA patients. which indicated GNRI was an objective and convenient albumin-weight index to identify myopenia in RA patients.

Retention rate of biologic and targeted synthetic anti-rheumatic drugs in elderly rheumatoid arthritis patients: data from GISEA registry

Objectives

An increased number of elderly individuals affected by rheumatoid arthritis (RA) has been reported, including both patients with RA onset in advanced age and patients aged with the disease. In this registry-based study, we aimed to analyze the retention rate and cause of discontinuation of biologic (b) and targeted synthetic (ts)-disease-modifying anti-rheumatic drugs (DMARDs) in RA patients over 65 year old.

Methods

RA patients enrolled in the Italian GISEA registry and starting a b- or a ts-DMARD over 65 years of age were included. Demographic, clinical, serologic, and therapeutic features were collected.

Results

A total of 1,221 elderly RA patients were analyzed (mean age 71.6 ± 5.2 years). RA was diagnosed before 65 years in 72.5% of cases, a 60.6% of patients experienced a previous b- or ts-DMARD. In patients older than 65 initiating a new b- or ts-DMARDS, tumor necrosis factor alpha inhibitors (TNFi) were prescribed in 29.6% of patients, abatacept in 24.8%, anti-interleukin 6 receptor antagonists (anti-IL6R) in 16.3%, Janus kinases inhibitors (JAKi) in 24.9%, and rituximab in 4.4%. The main causes of discontinuation were primary or secondary inadequate responses (66.1%). The median retention rate for all treatments was 181.3 weeks. A statistically higher retention rate was observed for abatacept when compared to TNFi (p = 0.02), JAKi (p < 0.001), and anti-IL6R (p < 0.001), and for TNFi vs. JAKi (p = 0.013).

Conclusion

We described, in a real-life setting, elderly RA patients treated with a biologic or a ts-DMARD in Italy. Loss of efficacy was the main cause of discontinuation, and the DMARD safety profile suggests that age does not contraindicate their use. Our study reinforced that the control of disease activity is mandatory.

Adipokines in Rheumatoid Arthritis: Emerging Biomarkers and Therapeutic Targets

Rheumatoid arthritis (RA) is a chronic inflammatory disease manifested by joint involvement, extra-articular manifestations, and general symptoms. Adipose tissue, previously perceived as an inert energy storage organ, has been recognised as a significant contributor to RA pathophysiology. Adipokines modulate immune responses, inflammation, and metabolic pathways in RA. Although most adipokines have a pro-inflammatory and aggravating effect on RA, some could counteract this pathological process. The coexistence of RA and sarcopenic obesity (SO) has gained attention due to its impact on disease severity and outcomes. Sarcopenic obesity further contributes to the inflammatory milieu and metabolic disturbances. Recent research has highlighted the intricate crosstalk between adipose tissue and skeletal muscle, suggesting potential interactions between these tissues in RA. This review summarizes the roles of adipokines in RA, particularly in inflammation, immune modulation, and joint destruction. In addition, it explores the emerging role of adipomyokines, specifically irisin and myostatin, in the pathogenesis of RA and their potential as therapeutic targets. We discuss the therapeutic implications of targeting adipokines and adipomyokines in RA management and highlight the challenges and future directions for research in this field.

Multimodal ultrasound muscle assessment in patients with rheumatic diseases: a patient-based reliability study

Objectives

The aim was to explore the inter-reliability of a newly developed US scanning protocol (multimodal US) for the assessment of different aspects of sarcopenia-related muscle involvement, including muscle mass, muscle quality and muscle stiffness [using point shear-wave elastography (SWE)], in patients with rheumatic and musculoskeletal diseases (RMDs).

Methods

Quadriceps muscle mass (i.e. muscle thickness), muscle quality (i.e. muscle echogenicity evaluated with both a visual semi-quantitative scale and a dedicated software package for image analysis, ImageJ) and point SWE measurements were obtained by two rheumatologists (blinded to each other's evaluation) in consecutive RMD patients without previous/current myositis or neuromuscular disorders.Inter-reliability was assessed using the intraclass correlation coefficient (ICC) for continuous variables and Cohen's kappa (κ) for categorical variables.

Results

A total of 45 RMD patients were enrolled [mean age 54.5 (16.0) years, male-to-female ratio 1:1.5, mean BMI 24.6 (4.6) kg/m2], 10 with PsA, 7 RA, 5 AS, 5 PMR, 4 SLE, 4 gout, 4 OA, 3 FM and 3 SSc. The grade of inter-rater reliability was excellent for muscle mass [ICC = 0.969 (0.953 < ICC < 0.979)]. Regarding muscle echogenicity, the agreement was substantial/almost perfect using the visual semi-quantitative scale (weighted linear = 0.793, weighted squared = 0.878) and excellent using ImageJ analysis [ICC = 0.916 (0.876 < ICC < 0.944)]. Finally, a good agreement was obtained for point SWE measurements [ICC = 0.76 (0.712 < ICC < 0.8)].

Conclusion

Multimodal US is a novel and reliable tool for the evaluation of different aspects of muscle involvement (muscle mass, muscle quality and muscle stiffness) in RMD patients.

Combined Effects of Diet and Physical Activity on Inflammatory Joint Disease: A Systematic Review and Meta-Analysis

Research evidence suggests that, individually, diet and physical activity are effective interventions for reducing levels of inflammation in inflammatory joint diseases (IJD), however little is known about their combined use. This systematic review and meta-analysis aimed to examine the effects and/or associations of combined diet and physical activity interventions in IJD, specifically rheumatoid arthritis (RA) and the spondyloarthropathies (SpA) (PROSPERO registration number: CRD42022370993). Ten out of 11 eligible studies examined RA patients. We found that a combination of diet/nutrition and physical activity/exercise improved Health Assessment Questionnaire score (standardized mean difference = -1.36, confidence interval (CI) = (-2.43)-(-0.30), I2 = 90%, Z = 2.5, p = 0.01), while surprisingly they increased erythrocyte sedimentation rate (mean difference = 0.20, CI = 0.09-0.31, I2 = 0%, Z = 3.45, p < 0.01). No effects were found on C-reactive protein or weight (p > 0.05) of RA patients. We did not find studies in other IJDs that provided sufficient data for a meta-analysis. The narrative data synthesis provided limited evidence to address our research question. No firm conclusions can be made as to whether the combination of diet/nutrition and physical activity/exercise affects inflammatory load in IJDs. The results of this study can only be used as a means of highlighting the low-quality evidence in this field of investigation and the need for further and better-quality research.