Indicators of walking speed in rheumatoid arthritis: relative influence of articular, psychosocial, and body composition characteristics

Evaluation of walking activity and gait to identify physical and mental fatigue in neurodegenerative and immune disorders: preliminary insights from the IDEA-FAST feasibility study

BACKGROUND

Many individuals with neurodegenerative (NDD) and immune-mediated inflammatory disorders (IMID) experience debilitating fatigue. Currently, assessments of fatigue rely on patient reported outcomes (PROs), which are subjective and prone to recall biases. Wearable devices, however, provide objective and reliable estimates of gait, an essential component of health, and may present objective evidence of fatigue. This study explored the relationships between gait characteristics derived from an inertial measurement unit (IMU) and patient-reported fatigue in the IDEA-FAST feasibility study.

METHODS

Participants with IMIDs and NDDs (Parkinson's disease (PD), Huntington's disease (HD), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), primary Sjogren's syndrome (PSS), and inflammatory bowel disease (IBD)) wore a lower-back IMU continuously for up to 10 days at home. Concurrently, participants completed PROs (physical fatigue (PF) and mental fatigue (MF)) up to four times a day. Macro (volume, variability, pattern, and acceleration vector magnitude) and micro (pace, rhythm, variability, asymmetry, and postural control) gait characteristics were extracted from the accelerometer data. The associations of these measures with the PROs were evaluated using a generalised linear mixed-effects model (GLMM) and binary classification with machine learning.

RESULTS

Data were recorded from 72 participants: PD = 13, HD = 9, RA = 12, SLE = 9, PSS = 14, IBD = 15. For the GLMM, the variability of the non-walking bouts length (in seconds) with PF returned the highest conditional R2, 0.165, and with MF the highest marginal R2, 0.0018. For the machine learning classifiers, the highest accuracy of the current analysis was returned by the micro gait characteristics with an intrasubject cross validation method and MF as 56.90% (precision = 43.9%, recall = 51.4%). Overall, the acceleration vector magnitude, bout length variation, postural control, and gait rhythm were the most interesting characteristics for future analysis.

CONCLUSIONS

Counterintuitively, the outcomes indicate that there is a weak relationship between typical gait measures and abnormal fatigue. However, factors such as the COVID-19 pandemic may have impacted gait behaviours. Therefore, further investigations with a larger cohort are required to fully understand the relationship between gait and abnormal fatigue.

Muscle fibre morphometric analysis (MusMA) correlates with muscle function and cardiovascular risk prognosis

Morphometry of striated muscle fibres is critical for monitoring muscle health and function. Here, we evaluated functional parameters of skeletal and cardiac striated muscle in two experimental models using the Morphometric Analysis of Muscle Fibre tool (MusMA). The collagen-induced arthritis model was used to evaluate the function of skeletal striated muscle and the non-alcoholic fatty liver disease model was used for cardiac striated muscle analysis. After euthanasia, we used haeamatoxylin and eosin stained sections of skeletal and cardiac muscle to perform muscle fibre segmentation and morphometric analysis. Morphometric analysis classified muscle fibres into six subpopulations: normal, regular hypertrophic, irregular hypertrophic, irregular, irregular atrophic and regular atrophic. The percentage of atrophic fibres was associated with lower walking speed (p = 0.009) and lower body weight (p = 0.026), respectively. Fibres categorized as normal were associated with maximum grip strength (p < 0.001) and higher march speed (p < 0.001). In the evaluation of cardiac striated muscle fibres, the percentage of normal cardiomyocytes negatively correlated with cardiovascular risk markers such as the presence of abdominal adipose tissue (p = .003), miR-33a expression (p = .001) and the expression of miR-126 (p = .042) Furthermore, the percentage of atrophic cardiomyocytes correlated significantly with the Castelli risk index II (p = .014). MusMA is a simple and objective tool that allows the screening of striated muscle fibre morphometry, which can complement the diagnosis of muscle diseases while providing functional and prognostic information in basic and clinical research.

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.

Gait rehabilitation for foot and ankle impairments in early rheumatoid arthritis: a feasibility study of a new gait rehabilitation programme (GREAT Strides)

Background

Foot impairments in early rheumatoid arthritis are common and lead to progressive deterioration of lower limb function. A gait rehabilitation programme underpinned by psychological techniques to improve adherence, may preserve gait and lower limb function. This study evaluated the feasibility of a novel gait rehabilitation intervention (GREAT Strides) and a future trial.

Methods

This was a mixed methods feasibility study with embedded qualitative components. People with early (< 2 years) rheumatoid arthritis (RA) and foot pain were eligible. Intervention acceptability was evaluated using a questionnaire. Adherence was evaluated using the Exercise Adherence Rating Scale (EARS). Safety was monitored using case report forms. Participants and therapists were interviewed to explore intervention acceptability. Deductive thematic analysis was applied using the Theoretical Framework of Acceptability. For fidelity, audio recordings of interventions sessions were assessed using the Motivational Interviewing Treatment Integrity (MITI) scale. Measurement properties of four candidate primary outcomes, rates of recruitment, attrition, and data completeness were evaluated.

Results

Thirty-five participants (68.6% female) with median age (inter-quartile range [IQR]) 60.1 [49.4–68.4] years and disease duration 9.1 [4.0–16.2] months), were recruited and 23 (65.7%) completed 12-week follow-up. Intervention acceptability was excellent; 21/23 were confident that it could help and would recommend it; 22/23 indicated it made sense to them. Adherence was good, with a median [IQR] EARS score of 17/24 [12.5–22.5]. One serious adverse event that was unrelated to the study was reported. Twelve participants’ and 9 therapists’ interviews confirmed intervention acceptability, identified perceptions of benefit, but also highlighted some barriers to completion. Mean MITI scores for relational (4.38) and technical (4.19) aspects of motivational interviewing demonstrated good fidelity. The Foot Function Index disability subscale performed best in terms of theoretical consistency and was deemed most practical.

Conclusion

GREAT Strides was viewed as acceptable by patients and therapists, and we observed high intervention fidelity, good patient adherence, and no safety concerns. A future trial to test the additional benefit of GREAT Strides to usual care will benefit from amended eligibility criteria, refinement of the intervention and strategies to ensure higher follow-up rates. The Foot Function Index disability subscale was identified as the primary outcome for the future trial.

Trial registration

ISRCTN14277030

Supplementary Information

The online version contains supplementary material available at 10.1186/s40814-022-01061-9.

Evaluation of peripheral neuropathy in lower limbs of patients with rheumatoid arthritis and its relation to fall risk

Background

Rheumatoid Arthritis (RA) is a chronic disabling systemic disease characterized by joint inflammation, and extra-articular manifestations, including peripheral neuropathy, a condition that can be associated with changes in muscle strength, proprioception and postural balance contributing for the risk of falls. The objective of this study is to analyze the incidence of peripheral neuropathy in patients with RA and its association with the occurrence of falls.

Methods

Patients were assessed by an electroneuromyography (ENMG) exam and by a questionnaire on accidental falls occurrence in the previous 12 months. They were also assessed on balance by the Short Physical Performance Battery (SPPB), functionality by the Health Assessment Questionnaire (HAQ), disease activity by the Disease Activity Score (DAS-28), neuropathic pain by the Questionnaire for the Diagnosis of Neuropathic Pain (DN4), and cutaneous sensitivity of the feet by the monofilament testing of Semmes–Weinstein. Monthly calls on falls were made in the subsequent six months. Data analysis was performed using the Shapiro–Wilk test for normality and Spearman, Chi-square, and T-student correlation tests, with a significant P level ≤ 0.05.

Results

A sample of 33 patients were evaluated. The incidence of peripheral neuropathy was 48.5%, of which 68.7% were axonal and 31.3% myelinic. The sensorimotor type was present in 64.7%, motor in 17.6%, and sensorial in 11.7% of the cases. Neuropathy was associated to balance (P = 0.026), neuropathic pain (P = 0.016), deep tendon reflexes absence (P = 0,049), altered skin sensitivity of the feet (P = 0.029) and fear of falling (P = 0.001). No association was found between peripheral neuropathy and age, gender, disease activity, or functionality. No significant association was found between peripheral neuropathy and occurrence of falls, in a 12-month retrospective and 6-month prospective evaluation.

Conclusion

Peripheral neuropathy has a high incidence in patients with RA, and is related to neuropathic pain, altered postural balance, but not to the occurrence of falls.

A Comparative study on the assessment of dual task performance in rheumatic diseases

BACKGROUND

In task-oriented studies showed that the chronic pain is effective on dual tasks. Chronic pain is the main health problem that prevents mobility restriction and participation in most rheumatic diseases.

RESEARCH QUESTION

Do rheumatic diseases have an effect on dual task gait performance?

METHODS

This comparative-descriptive study included 75 individuals who aged 18-65 years and divided in two groups as Rheumatic Disease Group (RG; 23 women, 14 men) and Control Group (CG; 20 women, 18 men). The individuals have a chronic pain (> 3.4 cm according to Visual Analogue Scale, VAS) and Standardized Mini Mental State Examination score above 24 were included in this study as the RG. The individuals who were did not have any known disease were included in the CG. The health status of RG was evaluated with the Arthritis Impact Measurement Scale 2 (AIMS-2). The 10-meter Walk Test was applied under single and dual task conditions (dual task cognitive, DT_cognitive; dual task motor, DT_motor) for assessing gait performance.

RESULTS AND SIGNIFICANCE

The mean age of the individuals in the study was 40.6 ± 11.34 years (RG=43.08 ± 11.30; CG=38.18 ± 11.00). There was a significant difference in favor of CG between the groups both in terms of gait speed in DT_cognitive and its cost (p < 0.05). VAS scores correlate with single and DT_cognitive and DT_motor gait parameters (p < 0.05). Many subdivisions of AIMS-2 were associated with single, DT_cognitive and DT_motor gait parameters (p < 0.05). This study concluded that rheumatic diseases may reduce gait performance in concurrent motor-cognitive dual task conditions due to chronic pain. Single and dual task gait parameters may be related with psychosocial factors. Therefore, applications including pain control and biopsychosocial approach may be beneficial in the management gait disturbances and falls due to a rheumatic disease.

The effects of resistance training with blood flow restriction on muscle strength, muscle hypertrophy and functionality in patients with osteoarthritis and rheumatoid arthritis: A systematic review with meta-analysis

Introduction

Rheumatoid arthritis(RA) and osteoarthritis(OA) patients showed systemic manifestations that may lead to a reduction in muscle strength, muscle mass and, consequently, to a reduction in functionality. On the other hand, moderate intensity resistance training(MIRT) and high intensity resistance training(HIRT) are able to improve muscle strength and muscle mass in RA and OA without affecting the disease course. However, due to the articular manifestations caused by these diseases, these patients may present intolerance to MIRT or HIRT. Thus, the low intensity resistance training combined with blood flow restriction(LIRTBFR) may be a new training strategy for these populations.

Objective

To perform a systematic review with meta-analysis to verify the effects of LIRTBFR on muscle strength, muscle mass and functionality in RA and OA patients.

Materials and methods

A systematic review with meta-analysis of randomized clinical trials(RCTs), published in English, between 1957–2021, was conducted using MEDLINE(PubMed), Embase and Cochrane Library. The methodological quality was assessed using Physiotherapy Evidence Database scale. The risk of bias was assessed using RoB2.0. Mean difference(MD) or standardized mean difference(SMD) and 95% confidence intervals(CI) were pooled using a random-effects model. A P<0.05 was considered statistically significant.

Results

Five RCTs were included. We found no significant differences in the effects between LIRTBFR, MIRT and HIRT on muscle strength, which was assessed by tests of quadriceps strength(SMD = -0.01[-0.57, 0.54], P = 0.96; I² = 58%) and functionality measured by tests with patterns similar to walking(SMD = -0.04[-0.39, 0.31], P = 0.82; I² = 0%). Compared to HIRT, muscle mass gain after LIRTBFR was reported to be similar. When comparing LIRTBFR with low intensity resistance training without blood flow restriction(LIRT), the effect LIRTBFR was reported to be higher on muscle strength, which was evaluated by the knee extension test.

Conclusion

LIRTBFR appears to be a promising strategy for gains in muscle strength, muscle mass and functionality in a predominant sample of RA and OA women.

Falls in Rheumatoid Patients: Does Ankle and Foot Ultrasonography have a Predictive Role? A Single-blind Study

Background Rheumatoid arthritis (RA) patients have a higher prevalence of falls compared with the healthy population. Several risk factors of falls in RA have been postulated, including high disease activity, low balance, muscle weakness and non-treatment with biologics.

Aim of the work We investigated our hypothesis that the sonographically detected ankle and foot changes in RA patients can predict falls in this population. To our knowledge, no previous study had investigated this before.

Methods In a total of 101 RA patients, we performed assessments of disease activity, disability level, gait speed, balance status, clinical examination of ankle and foot and an MSUS assessment of the ankle and foot joints and tendons as possible risk factors of falls.

Results The Berg balance test had the highest fall-predicting power (71.3%), followed by a gait speed test and restricted range of motion (ROM) of the Rt. subtalar joint, each with a predictive power of 70.3%. Of the sonographic findings, erosion of the first metatarsophalangeal (MTP) joint was the most accurate fall predictor, followed by erosion of the talonavicular joint and tenosynovitis of the ankle dorsal flexors with an area under the curve of 0.656, 0.642 and 0.614, respectively.

Conclusion The use of the MSUS as an adjunct objective method for predicting falls in RA patients has not been studied before. It was found that clinical foot and balance testing was a superior and easier way of predicting falls in RA patients than using ultrasonography.

The Effect of TNF and Non-TNF-Targeted Biologics on Body Composition in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is associated with a decrease in lean mass and stability or even an increase in fat and ectopic adipose tissue. A few data are available on body composition changes under treatment, and data are still controversial. Body composition was assessed before initiation of biologic disease-modifying antirheumatic drug (bDMARD) and after 6 and 12 months of stable treatment. Eighty-three RA patients were included (75% of women, mean age 58.5 ± 10.8 years) of whom 47 patients treated with TNF inhibitor (TNFi), 18 with non-TNF-targeted biologic (Non-TNFi), and 18 with conventional DMARD (cDMARD) alone. In the TNFi group, total lean mass, fat-free mass index, and skeletal muscle mass index significantly increased at 1 year. An increase in subcutaneous adipose tissue (SAT) without change for the visceral or body fat composition was associated. These changes were associated with an improvement in strength and walking test. In non-TNFi or cDMARD groups, no significant changes for body composition or muscle function were observed at 1 year. However, no significant differences for treatment x time interaction were noted between group treatments. In active RA patients starting first bDMARD, treatment with TNFi over 1 year was associated with favorable changes of the body composition and muscle function.

Ultrasound measurement of muscle thickness at the anterior thigh level in rheumatology setting: a reliability study

Ultrasound (US) is a promising tool for assessing sarcopenia. We aimed to test in the rheumatology setting two US scanning protocols to measure muscle thickness (MT) at the anterior thigh level and to assess their feasibility and reliability. In the first phase of the study, three rheumatologists performed a US examination on 19 consecutive patients adopting two scanning protocols, namely the anterior superior iliac spine (ASIS) and the greater trochanter techniques. After consensus was obtained on the easiest scanning protocol to perform, two rheumatologists adopted only the ASIS technique in 40 consecutive patients. MT measurements were recorded as well as the time needed to complete each scanning protocol bilaterally. The median time needed to complete the US examination was under 5 minutes for each of the two techniques, with no significant difference between them (p = 0.64). In the first phase, we found an excellent inter-observer reliability of the proposed scanning protocols, with a higher but nonstatistically significant intraclass correlation coefficient (ICC) for the ASIS technique compared with the greater trochanter technique (ICC 0.97 vs. ICC 0.92, p = 0.05). The ASIS technique had a significantly higher intra-observer reliability (ICC 0.97 vs. ICC 0.92, p < 0.01). In the second phase, the ASIS technique confirmed on a larger sample its excellent inter-observer reliability, with an ICC of 0.96. The present study presents a novel tool for assessing sarcopenia and provides evidence in favor of feasibility and reliability of US measurement of MT at the anterior thigh level in rheumatology setting. Key Points • This study demonstrates that ultrasound (US) measurement of muscle thickness at the anterior thigh level is highly reliable, especially for the "anterior superior iliac spine (ASIS)" technique. • The short time needed to complete the US assessment highlights the feasibility of the proposed scanning protocols. • The simplicity and conciseness of the proposed techniques will allow other researchers and clinicians to use it for a fast assessment of sarcopenia.

Management of inflammatory rheumatic conditions in the elderly

The number of elderly people with chronic inflammatory rheumatic diseases is increasing. This heterogeneous and comorbid population is at particular risk of cardiovascular, neoplastic, infectious and iatrogenic complications. The development of biotherapies has paved the way for innovative therapeutic strategies, which are associated with toxicities. In this review, we have focused on the scientific and therapeutic changes impacting the management of elderly patients affected by RA, SpA or PsA. A multidimensional health assessment resulting in an integrated therapeutic strategy was identified as a major research direction for improving the management of elderly patients.

Could Omega 3 Fatty Acids Preserve Muscle Health in Rheumatoid Arthritis?

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by a high prevalence of death due to cardiometabolic diseases. As observed during the aging process, several comorbidities, such as cardiovascular disorders (CVD), insulin resistance, metabolic syndrome and sarcopenia, are frequently associated to RA. These abnormalities could be closely linked to alterations in lipid metabolism. Indeed, RA patients exhibit a lipid paradox, defined by reduced levels of total, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol whereas the CVD risk is increased. Moreover, the accumulation of toxic lipid mediators (i.e., lipotoxicity) in skeletal muscles can induce mitochondrial dysfunctions and insulin resistance, which are both crucial determinants of CVD and sarcopenia. The prevention or reversion of these biological perturbations in RA patients could contribute to the maintenance of muscle health and thus be protective against the increased risk for cardiometabolic diseases, dysmobility and mortality. Yet, several studies have shown that omega 3 fatty acids (FA) could prevent the development of RA, improve muscle metabolism and limit muscle atrophy in obese and insulin-resistant subjects. Thereby, dietary supplementation with omega 3 FA should be a promising strategy to counteract muscle lipotoxicity and for the prevention of comorbidities in RA patients.

When You Can't Walk a Mile: Walking Limitation Prevalence and Associations Among Middle-Aged and Older US Adults with Arthritis: A Cross-Sectional, Population-Based Study

OBJECTIVE

We examined walking limitations and associated characteristics among middle-aged and older US adults with arthritis, overall, and by sex.

METHODS

Using 2005-2006 Arthritis Conditions and Health Effects Survey (ACHES) data (n = 1793), we estimated "a lot" and "any" ("a lot" or "a little" combined) walking limitation for more than 1 mile (1.6 km) among US adults 45 years or older with arthritis and examined associations (sociodemographics, arthritis symptoms and effects, psychosocial measures, and physical health) with walking limitations in unadjusted and multivariable (MV) adjusted logistic regression models using prevalence ratios (PRs) and 95% confidence intervals, accounting for the complex survey design.

RESULTS

Respondents frequently reported "a lot" (48%) and "any" (72%) limitation for more than 1 mile. Women reported higher prevalence of all levels of walking limitation versus men (eg, 51% vs 42% for "a lot" overall); additionally, the gap for walking limitations between women and men widened with age. Limitation was high for both sexes at all ages, affecting 1-in-3 to 4-in-5, depending on level of walking limitation. The strongest MV associations for "a lot" of walking limitation among all respondents included substantial and modest arthritis-attributable life interference (PR = 2.5 and 1.6, respectively), age 75 years or older (PR = 1.5), and physical inactivity and fair/poor self-rated health (PR = 1.4 for both).

CONCLUSION

Walking limitations among middle-aged and older adults are substantial. Existing proven interventions that improve walking ability and physical function may help this population to reduce and delay disability.

Sarcopenia

Sarcopenia is defined as a combination of low muscle mass with low muscle function. The term was first used to designate the loss of muscle mass and performance associated with aging. Now, recognized causes of sarcopenia also include chronic disease, a physically inactive lifestyle, loss of mobility, and malnutrition. Sarcopenia should be differentiated from cachexia, which is characterized not only by low muscle mass but also by weight loss and anorexia. Sarcopenia results from complex and interdependent pathophysiological mechanisms that include aging, physical inactivity, neuromuscular compromise, resistance to postprandial anabolism, insulin resistance, lipotoxicity, endocrine factors, oxidative stress, mitochondrial dysfunction, and inflammation. The prevalence of sarcopenia ranges from 3% to 24% depending on the diagnostic criteria used and increases with age. Among patients with rheumatoid arthritis 20% to 30% have sarcopenia, which correlates with disease severity. Sarcopenia exacts a heavy toll of functional impairment, metabolic disorders, morbidity, mortality, and healthcare costs. Thus, the consequences of sarcopenia include disability, quality of life impairments, falls, osteoporosis, dyslipidemia, an increased cardiovascular risk, metabolic syndrome, and immunosuppression. The adverse effects of sarcopenia are particularly great in patients with a high fat mass, a condition known as sarcopenic obesity. The diagnosis of sarcopenia rests on muscle mass measurements and on functional tests that evaluate either muscle strength or physical performance (walking, balance). No specific biomarkers have been identified to date. The management of sarcopenia requires a multimodal approach combining a sufficient intake of high-quality protein and fatty acids, physical exercise, and antiinflammatory medications. Selective androgen receptor modulators and anti-myostatin antibodies are being evaluated as potential stimulators of muscle anabolism.

Correlates of sedentary behaviour and light physical activity in people living with rheumatoid arthritis: protocol for a longitudinal study

BACKGROUND

Sedentary behaviour (SB) is associated with adverse health outcomes in the general population. Replacing sedentary time with light intensity physical activity (LPA) has been linked with improvements in all-cause and cardiovascular disease mortality in adults. People with Rheumatoid Arthritis (RA) typically spend long periods of time sedentary, but the health consequences of 'too much sitting', and possible benefits of LPA, have not been fully explored in this population. Moreover, little is known regarding the determinants of these behaviours among people living with RA, and such knowledge is required for the development of effective behavioural interventions.

AIMS

To examine longitudinal relationships between: 1) objectively-assessed SB/LPA with health outcomes in RA, 2) hypothesised determinants of SB/LPA with objectively-assessed SB/LPA in RA.

METHODS

This longitudinal study will secure assessments at baseline (Time 1) and 6-month follow-up (Time 2) from RA patients. At both time points, physical assessments will be undertaken, and questionnaires administered to measure physical (e.g., percentage body fat, disease activity, physical function, pain) and psychological (e.g., depression, anxiety, vitality) health outcomes. Additional questionnaires will be administered to establish hypothesised determinants (i.e., psychosocial, individual differences, and physical environmental). Participants will wear the ActiGraph GT3X accelerometer and activPAL3μTM for 7 days to objectively measure SB and LPA.

DISCUSSION

Findings will elucidate the health correlates of SB in RA, as well as the relevance of interventions targeting reductions in SB by promoting LPA. Results will also assist in identifying intervention targets (i.e., determinants), with the potential to encourage SB change in RA.

Can Creatine Supplementation Improve Body Composition and Objective Physical Function in Rheumatoid Arthritis Patients? A Randomized Controlled Trial

OBJECTIVE

Rheumatoid cachexia (muscle wasting) in rheumatoid arthritis (RA) patients contributes to substantial reductions in strength and impaired physical function. The objective of this randomized controlled trial was to investigate the effectiveness of oral creatine (Cr) supplementation in increasing lean mass and improving strength and physical function in RA patients.

METHODS

In a double-blind design, 40 RA patients were randomized to either 12 weeks' supplementation of Cr or placebo. Body composition (dual x-ray absorptiometry and bioelectrical impedance spectroscopy [BIS]), strength, and objectively assessed physical function were measured at baseline, day 6, week 12, and week 24. Data analysis was performed by analysis of covariance.

RESULTS

Cr supplementation increased appendicular lean mass (ALM; a surrogate measure of muscle mass) by mean ± SE 0.52 ± 0.13 kg (P = 0.004 versus placebo), and total LM by 0.60 ± 0.37 kg (P = 0.158). The change in LM concurred with the gain in intracellular water (0.64 ± 0.22 liters; P = 0.035) measured by BIS. Despite increasing ALM, Cr supplementation, relative to placebo, failed to improve isometric knee extensor strength (P = 0.408), handgrip strength (P = 0.833), or objectively assessed physical function (P = 0.335-0.764).

CONCLUSION

In patients with RA, Cr supplementation increased muscle mass, but not strength or objective physical function. No treatment-related adverse effects were reported, suggesting that Cr supplementation may offer a safe and acceptable adjunct treatment for attenuating muscle loss; this treatment may be beneficial for patients experiencing severe rheumatoid cachexia.

Tight control of disease activity fails to improve body composition or physical function in rheumatoid arthritis patients

OBJECTIVE

RA typically features rheumatoid cachexia [loss of muscle mass (MM) and excessive total fat mass (TFM), especially trunk FM], which contributes to physical disability. Since rheumatoid cachexia is driven by inflammation, it would be anticipated that the success of tight control of disease activity, such as treat-to-target (T2T), in attenuating inflammation would benefit body composition and physical function. This aim of this cross-sectional study was to assess the impact of T2T on body composition and objectively assessed function in RA patients.

METHODS

A total of 82 RA patients exclusively treated by T2T, were compared with 85 matched sedentary healthy controls (HCs). Body composition was estimated by DXA, with appendicular lean mass the surrogate measure of total MM. Physical function was assessed by knee extensor strength, handgrip strength, 30 s sit-to-stands, 8' up and go, and 50' walk (tests which reflect the ability to perform activities of daily living).

RESULTS

Although generally well treated (mean DAS28 = 2.8, with 49% in remission), RA patients had ∼10% proportionally less appendicular lean mass and were considerably fatter (by ∼27%), particularly in the trunk (∼32%), than HCs. All measures of function were 24-34% poorer in the RA patients relative to HC.

CONCLUSIONS

Despite marked improvements in disease control (most patients achieving or approaching remission), the relative loss of MM and increased adiposity in RA patients compared with matched HCs was similar to that observed pre-T2T. Additionally, performance of objective function tests was unchanged from that reported by our group for pre-T2T RA patients. Thus T2T, even in responsive RA patients, did not attenuate rheumatoid cachexia or improve objectively assessed function.

Cachexia and adiposity in rheumatoid arthritis. Relevance for disease management and clinical outcomes

Altered body composition is a frequent finding in rheumatoid arthritis and is associated with the two major outcomes of the disease: disability and cardiovascular mortality. It is estimated that up to two thirds of patients may be affected by loss of lean mass, the so-called rheumatoid cachexia. Hence, body weight being equal, the relative amount of lean mass is lower and that of body fat is higher in rheumatoid arthritis patients vs. healthy controls. Both disease-related factors and other factors, like drug treatments, physical activity and nutrition contribute to modify body composition in rheumatoid arthritis. The effect of pharmacological treatments, and notably of anti-TNF drugs, on body composition is controversial. Conversely, training programs to stimulate muscle growth can restore lean mass and reduce adiposity. There is good evidence that amelioration of body composition ameliorates function and reduces disability. Currently, there is no evidence that interventions that modify body composition can reduce cardiovascular morbidity and mortality in rheumatoid arthritis.