The bioimpedance phase angle may be associated with frailty in rheumatoid arthritis patients: Results from a prospective, cohort study.

OBJECTIVES: This study investigated whether the phase angle (PhA) on bioelectrical impedance analysis is related to frailty in rheumatoid arthritis (RA) patients. METHODS: Data from a prospective cohort study of RA patients were analysed. The PhA was assessed by the bioelectrical impedance analysis method, and frailty was assessed by the Kihon Check List (KCL) annually. The cut-off value of the PhA for frailty was calculated by receiver-operating characteristic analysis. The relationships between the PhA and frailty were evaluated by logistic regression analysis. The relationships between the change in PhA and frailty status and the KCL score were evaluated by analysis of covariance and multiple regression analysis. RESULTS: A total of 170 patients (81.2% female, 66.2 ± 13.1 years) were included in the analysis. A PhA of less than the cut-off for frailty was significantly associated with frailty (odds ratio: 4.75, 95% confidence interval: 1.86, 12.17). The change in the PhA was significantly associated with the change in the KCL score (ß = -0.15). In robust patients, there was a significant difference in the rate of change of the PhA between the group that became pre-frail in the next year and the group that remained robust. CONCLUSIONS: The PhA may be associated with frailty in RA patients.

Neck pain and related factors in patients with rheumatoid arthritis.

OBJECTIVES: In rheumatoid arthritis, neck pain can be caused by inflammatory reactions or cervical lesions, but the prevalence and associated factors have not been well studied. This study aimed to investigate the prevalence of neck pain in patients with rheumatoid arthritis and elucidate the related factors. METHODS: This study included 146 patients with rheumatoid arthritis. Neck pain, quality of life, and levels of anxiety and depression were evaluated using a questionnaire. Cervical lesions and spinal alignment were evaluated using plain radiograph and magnetic resonance imaging. Factors associated with neck pain were analysed using a logistic regression model. RESULTS: Fifty-six per cent of the patients had neck pain, and the quality of life scores were significantly worse in these patients. Multivariate analysis revealed age, C7 sagittal vertical axis, upper cervical lesion, and endplate erosion as factors associated with neck pain in patients with rheumatoid arthritis. CONCLUSIONS: More than half the patients with rheumatoid arthritis suffer from neck pain, and neck pain affects the quality of life and activities of daily living. Neck pain was associated with upper cervical lesion and endplate erosion suggesting the importance of radiological examination in patients with rheumatoid arthritis and neck pain.

Incidence of new carotid plaques in rheumatoid arthritis patients: 6-Year prospective results of the TOMORROW study.

OBJECTIVES: The purpose of this study was to evaluate the new incidence of carotid plaques in rheumatoid arthritis (RA) patients over a 6-year prospective follow-up and to assess the risk factors. METHODS: This is a 10-year prospective cohort study that included 208 RA patients and 205 age- and gender-matched controls. Ultrasound assessment of the bilateral carotid arteries was performed in 2011 and 2017. RESULTS: There were no differences in the incidence of new carotid atherosclerotic plaques over 6 years between the two groups (35.5% vs. 37.0%, respectively; p = .936). The mean Disease Activity Score 28-C-reactive protein over 6 years in RA patients was 2.73 ± 0.95. Multiple logistic regression analysis showed that RA was not a risk factor for new carotid atherosclerotic plaques (odds ratios, 0.708; 95% confidence interval, 0.348-1.440; p = .340). An average glucocorticoid dose of >1.8 mg/day over 6 years was a risk factor for new carotid atherosclerotic plaques (odds ratios, 8.54; 95% confidence interval, 1.641-44.455; p = .011). CONCLUSIONS: Incidence of new carotid atherosclerotic plaques was similar between well-controlled disease activity RA patients and control subjects. A mean glucocorticoid dose of >1.8 mg/day over 6 years was a risk factor for new carotid atherosclerotic plaques.

Comparison of clinical and radiographic results of mobile-bearing total ankle arthroplasty between osteoarthritis and rheumatoid arthritis.

OBJECTIVES: Clinical results of mobile-bearing total ankle arthroplasty (TAA) for rheumatoid arthritis (RA) have been reported, but no studies have compared osteoarthritis (OA) and RA. Clinical and radiographic outcomes after at least 3 years were compared between OA and RA. METHODS: Eleven ankles with OA and 22 ankles with RA were followed after mobile-bearing TAA (FINE total ankle system). Clinical outcomes were assessed by the American Orthopaedic Foot and Ankle Society (AOFAS) score. Radiographic outcomes were evaluated by the angular position of the implant, radiolucent lines, migration, and subsidence. Operative and postoperative complications were assessed. RESULTS: There were no significant differences in clinical outcomes, radiographic outcomes, or complications, except the final follow-up AOFAS total score (OA: 89.4 vs RA: 78.2; p = .044) and pain score (OA: 37.3 vs RA: 30.5; p = .041) at a mean follow-up of 83.4 months. Delayed wound healing occurred in 9.1% in RA and none in OA. Radiolucent lines were observed in 45% of both groups, and implant removal was performed in 9.1% and 18.2% of OA and RA, respectively; there were no significant differences. CONCLUSIONS: The final follow-up AOFAS total score and pain score were significantly higher in OA after the FINE total ankle system. There was a discrepancy between radiographic abnormalities and implant removal in both OA and RA.

Impact of disease burden or inflammation on nutritional assessment by the GLIM criteria in female patients with rheumatoid arthritis.

BACKGROUND & AIMS: In 2018, the Global Leadership Initiative on Malnutrition (GLIM) released a global standard for evaluating malnutrition. The etiologies of malnutrition in the GLIM criteria includes disease burden/inflammation, but how this view affects nutritional assessment remains unclear. This study aimed to investigate the impact of disease burden/inflammation on the proportion of malnourished patients defined by GLIM criteria, and how differences in methods for determining disease burden/inflammation in GLIM criteria affect existing nutritional indices among patients with rheumatoid arthritis (RA). We also investigated factors associated with malnutrition in RA patients. METHODS: Data from 135 female RA patients (66.8 ± 12.6 years) were cross-sectionally analyzed. Among the etiologies of malnutrition, disease burden/inflammation was defined as: (1) moderate or higher disease activity score (disease activity score composite of the 28-joint score and erythrocyte sedimentation rate [DAS28-ESR] ≥ 3.2) [DAS-malnutrition (MN)]; (2) elevated C-reactive protein (CRP) ≥0.5 mg/dL (CRP-MN); and (3) presence of RA (RA-MN). In each of the three conditions, nutritional indicators between well-nourished and malnourished groups were compared by analysis of covariance. Factors associated with malnutrition were analyzed with logistic regression analysis. RESULTS: The frequencies of malnutrition as defined by DAS-MN, CRP-MN, and RA-MN were 39%, 30%, and 71%, respectively. When malnutrition was defined by the DAS-MN and/or the CRP-MN, grip strength and serum ceruloplasmin, iron, and zinc levels showed significant differences between the well-nourished and malnourished groups (p < 0.05). The use of targeted synthetic or biological disease-modifying antirheumatic drugs (ts-/b-DMARD) (OR = 0.29; 95% CI 0.11-0.82), grip strength (OR = 0.83; 95% CI 0.75-0.91), subjective reduction in walking speed (OR = 5.24; 1.85-14.86) were significantly associated with malnutrition as determined by DAS-MN. CONCLUSION: Differences in disease burden/inflammation affect nutritional assessments. The number of malnourished patients with RA was negatively associated with the use of ts-/b-DMARDs and high physical function in women.

Risk factors for poor response to denosumab treatment in Japanese postmenopausal women with osteoporosis.

INTRODUCTION: Denosumab has been reported to increase bone mineral density (BMD) and suppress fractures, but poor responders are not uncommon. This study aimed to identify risk factors for poor response to denosumab treatment. This is the first study to explore risk factors for poor response to denosumab. MATERIALS AND METHODS: This retrospective observational study investigated 227 Japanese postmenopausal women who received denosumab with monitoring of BMD by dual-energy X-ray absorptiometry at 6-month intervals. Risk factors were identified using Cox's proportional hazard modeling. Poor responders were defined as not exceeding the least significant change of BMD from baseline for 3 years. RESULTS: Mean relative change from baseline for 3 years in lumbar spine (LS)-BMD, femoral neck (FN)-BMD, and total hip (TH)-BMD were 12.6%, 6.8%, and 6.1%, respectively. Numbers of poor responders were 10 in LS-BMD, 47 in FN-BMD, 38 in TH-BMD. Risk factors for poor response were concomitant glucocorticoid use for LS-BMD, low body mass index or initiation at higher BMD for FN-BMD, and pretreatment with bisphosphonates or initiation at higher BMD for TH-BMD. CONCLUSION: Risk factors for insufficient denosumab effect differed between BMD measurement sites. These results should be taken into consideration when selecting denosumab in clinical practice.

A case of successful radiofrequency catheter ablation for atrial tachycardia originating from the inferior vena cava using high-resolution mapping.

A 60-year-old man presented with sustained supraventricular tachycardia. Atrial tachycardia (AT), with the earliest atrial activation (EAA) occurring at the ostium of the coronary sinus, was reproducibly induced. Three-dimensional electroanatomical mapping (3DEAM) using a 3.5-mm distal electrode tip linear catheter (Thermocool) and radiofrequency energy (RF) was performed at the fractionated atrial electrogram site. It preceded at 30 ms to the EAA but did not terminate AT. Further 3DEAM using a multielectrode mapping catheter (Pentaray) demonstrated a centrifugal propagation pattern at the boundary zone between the right atrium and inferior vena cava. RF application here terminated AT, which then became non-inducible.

The bioimpedance phase angle is more useful than sarcopenia as a predictor of falls in patients with rheumatoid arthritis: Results from a 2-y prospective cohort study.

OBJECTIVES: The phase angle (PhA) is an index derived by bioelectrical impedance analysis that reflects the fragility of cell membranes, muscle mass, muscle strength, and nutritional status, and a decrease in PhA might be associated with falls. This study aimed to investigate the relationships of the PhA with sarcopenia and falls in patients with rheumatoid arthritis (RA). METHODS: Data from a prospective cohort study of 189 patients with RA (age 66.5 ± 13.3 y; 80% women) were analyzed. PhA, muscle mass, and grip strength (GS) were evaluated. Sarcopenia was assessed using the Asian Working Group for Sarcopenia 2014 criteria. The correlation between PhA and GS was investigated, and the cutoff value of the PhA for falls during a 2-y period was estimated with a receiver operating characteristic curve analysis. The effects of the PhA and sarcopenia on falls were examined with a Cox proportional hazards model. RESULTS: Of the 189 patients, 48 (25.4%) had falls. The PhA was significantly positively correlated with GS (r = 0.58; P < 0.001). The cutoff values for the PhA for falls were 4.06° for women and 5.26° for men. In the Cox proportional hazards model adjusted for sex, age, disease activity, glucocorticoid use, and activities of daily living at baseline, the hazard ratio for falls was significantly higher when the PhA was below the cutoff value at baseline (hazard ratio: 2.29; 95% confidence interval, 1.18-4.45). Sarcopenia was not a significant risk factor for falls. CONCLUSIONS: The PhA might be a useful surrogate marker to predict falls in patients with RA.

Incidence of and risk factors for spondylolisthesis, scoliosis, and vertebral fracture in rheumatoid arthritis.

INTRODUCTION: Although lumbar lesions such as spondylolisthesis, scoliosis, and vertebral fracture are not specific to rheumatoid arthritis (RA), the prevalence is high in RA patients. However, no longitudinal study has evaluated lumbar lesions in RA. This study aimed to investigate the incidence of and risk factors for lumbar lesions in RA by a prospective longitudinal cohort study. MATERIALS AND METHODS: The study cohort comprised 110 patients with RA from the 'analysis of factors for RA spinal disorders (AFFORD)' study who completed the secondary survey at a single orthopaedic outpatient RA clinic. Radiological examination included standing radiographs and magnetic resonance imaging (MRI) of the lumbar spine. New development of spondylolisthesis, scoliosis, and vertebral fracture were assessed between baseline and secondary survey. RESULTS: The incidences of spondylolisthesis, scoliosis, and vertebral fracture were 42%, 16%, and 12%, respectively, during a mean follow-up of 7 years. The independent risk factor for de novo scoliosis was poor control of RA (adjusted odds ratio [aOR] 4.81, p = 0.011), while the independent risk factors for new vertebral fracture was use of glucocorticoid at secondary survey (aOR 14.87, p = 0.012). Patients with de novo scoliosis exhibited more severe low back pain and lower quality of life than those without. CONCLUSION: The incidence of scoliosis was related in patients with poor control of RA, while new vertebral fracture was more common in patients with use of glucocorticoid. Control of disease activity might be important in preventing radiological lumbar disorders in RA.

Risk factors for low back pain increase in rheumatoid arthritis: Analysis of a 7-year follow-up study.

OBJECTIVE: Several studies have demonstrated that low back pain (LBP) is related to disease activity in patients with rheumatoid arthritis (RA). However, there is no longitudinal research. This study aimed to determine the impacts and risk factors for LBP increase in RA in a longitudinal cohort study. METHODS: The study evaluated 113 patients with RA who completed the secondary survey. LBP increase was defined as ≥1 standard deviation of mean change in visual analogue scale (VAS) between the baseline and secondary surveys. The impacts of LBP increase on quality of life (QOL) and psychological status were evaluated. Risk factors were assessed among patient demographic characteristics and radiological changes. RESULTS: Mean change in VAS for LBP was -0.8 ± 30.4 mm during a mean 7-year follow-up. LBP increase was defined as ≥30-mm increase in VAS for LBP. Patients with LBP increase had significantly lower QOL and worse mental status than patients without it. Poor control of RA was identified as an independent risk factor for LBP increase (odds ratio, 9.82, p = .001). CONCLUSION: Patients with poor control of RA were likely to experience LBP increase in the long term. Control of RA disease activity is important for control of LBP, QOL, and mental status.

Double-blinded randomized controlled trial to reveal the effects of Brazilian propolis intake on rheumatoid arthritis disease activity index; BeeDAI.

BACKGROUND AND AIMS: Brazilian propolis reportedly contributed to suppressing disease activity in a mouse model of rheumatoid arthritis (RA), suggesting new treatment options using Brazilian propolis. However, only results from animal experiments have been available, and the suppressive effects of Brazilian propolis on disease activity in humans with RA remain unknown. The purpose of this study was to clinically validate how Brazilian propolis intake changes disease activity in RA patients. METHODS: This study was conducted as a multicenter, double-blinded, randomized, placebo-controlled, parallel-group study of 80 women with RA (median age, 61.5 years; interquartile range, 56.0 to 67.3 years) showing moderate disease activity on Disease Activity Score in 28 joints using erythrocyte sedimentation rate (DAS28-ESR). Test tablets containing Brazilian propolis were used in Group P (40 patients), and Brazilian propolis-free placebo tablets were used as control in Group C (40 patients). Group P received 5 tablets of propolis (508.5 mg of propolis) daily, and Group C received 5 tablets of placebo daily. The intervention lasted 24 weeks, with change in DAS28-ESR set as the primary endpoint. As secondary endpoints, other disease activity assessment (DAS28 using C-reactive protein, simplified disease activity index, clinical disease activity index), ultrasonographic evaluation of synovitis, activities of daily living, quality of life, changes in cytokine levels, and adverse events over the course of the study were also assessed. Data were statistically analyzed by analysis of covariance. RESULTS: No significant differences in the primary endpoint were identified between groups (Group P vs Group C, effect: 0.14, 95% confidence interval: -0.21 to 0.49, p = 0.427). Likewise, no significant differences were seen between groups for any secondary endpoints. The adverse event rate during the study period was 28% in Group P and 33% in Group C. CONCLUSIONS: Brazilian propolis exerted no effects on disease activity in patients with RA.

Change in dietary inflammatory index score is associated with control of long-term rheumatoid arthritis disease activity in a Japanese cohort: the TOMORROW study.

BACKGROUND: The dietary inflammatory index (DII®), a quantitative measure of the inflammatory potential of daily food and nutrient intake, and associations between a variety of health outcomes have been reported. However, the association between DII score and disease activity of rheumatoid arthritis (RA) is unclear. Therefore, this study was designed to test whether higher DII score contributes to disease activity and as a corollary, whether reducing DII score helps to achieve or maintain low disease activity or remission in patients with RA. METHODS: We performed a cross-sectional and longitudinal analysis using 6 years of data (from 2011 to 2017) in TOMORROW, a cohort study consisting of 208 RA patients and 205 gender- and age-matched controls started in 2010. Disease activity of RA patients was assessed annually using DAS28-ESR (disease activity score 28 joints and the erythrocyte sedimentation rate) as a composite measure based on arthritic symptoms in 28 joints plus global health assessment and ESR. Dietary data were collected in 2011 and 2017 using the brief-type self-administered diet history questionnaire (BDHQ). Energy-adjusted DII (E-DII™) score was calculated using 26 nutrients derived from the BDHQ. Data were analyzed with two-group comparisons, correlation analysis, and multivariable logistic regression analysis. RESULTS: One hundred and seventy-seven RA patients and 183 controls, for whom clinical and dietary survey data were available, were analyzed. RA patients had significantly higher E-DII (pro-inflammatory) score compared to controls both in 2011 and 2017 (p < 0.05). In RA patients, E-DII score was not a factor associated with significant change in disease activity. However, anti-inflammatory change in E-DII score was associated maintaining low disease activity (DAS28-ESR ≤ 3.2) or less for 6 years (OR 3.46, 95% CI 0.33-8.98, p = 0.011). CONCLUSIONS: The diets of RA patients had a higher inflammatory potential than controls. Although E-DII score was not a factor associated with significant disease activity change, anti-inflammatory change in E-DII score appeared to be associated with maintaining low disease activity in patients with RA. TRIAL REGISTRATION: UMIN Clinical Trials Registry, UMIN000003876 . Registered 7 Aug 2010-retrospectively registered.

Change in skeletal muscle mass is associated with lipid profiles in female rheumatoid arthritis patients -TOMORROW study.

BACKGROUND & AIMS: To examine the relationship between changes in skeletal muscle mass and lipid metabolism and glycometabolism in patients with rheumatoid arthritis (RA). METHODS: Data were analyzed from 148 female RA patients and 145 age-matched non-RA (control) female subjects from a prospective cohort study (TOMORROW; TOtal Management Of Risk factors in Rheumatoid arthritis patients to lOWer morbidity and mortality study). Appendicular skeletal muscle mass (ASM) was assessed using dual-energy x-ray absorptiometry and skeletal muscle mass index (SMI) was calculated as ASM divided by the square of height. The reference value for SMI in Asian women, 5.4 kg/m2, was used to define low SMI. Data were assessed using cross-sectional (2010 baseline data) and longitudinal (change in value from 2010 to 2013) methods from the retrospective cohort. RESULTS: At baseline in RA patients, the low SMI group showed significantly higher low-density lipoprotein cholesterol (LDL-chol) (p = 0.015), apolipoprotein (Apo)B (p = 0.046), and ApoB-to-A1 (ApoB/A1) (p = 0.025) than the normal SMI group. In multiple regression analysis of RA patients, sequential changes from 2010 to 2013 (Δ) in SMI and ApoB and ApoC2 showed significant negative relationships (ß = -0.19, -0.18, respectively) even after adjusting for age, RA duration, exercise habits, medication for RA, disease severity, activities of daily living (ADL) and body fat mass. No significant relation was evident between ΔSMI and various glycometabolism parameters in RA patients. CONCLUSIONS: Skeletal muscle mass might be related to lipid metabolism in RA patients. This relationship is independent of factors such as disease severity and body fat mass.

Ultrasound assessment, unlike clinical assessment, reflects enthesitis in patients with psoriatic arthritis.

OBJECTIVES: Enthesitis is a major musculoskeletal manifestation of psoriatic arthritis (PsA). It is conventionally assessed clinically, by the presence of tenderness, despite its low reliability. However, ultrasound (US) provides a sensitive and feasible method for evaluating enthesitis. We investigated enthesitis as assessed clinically and by US in patients with PsA. METHODS: Forty-seven patients with PsA underwent US examination of the bilateral humeral medial epicondyles and insertions of the triceps, distal quadriceps, proximal/distal patellae, Achilles tendons, and plantar fascia. These 14 entheses were also clinically evaluated by tenderness. The correspondence between US and clinical enthesitis was evaluated, as well as their associations with inflammatory markers (C-reactive protein [CRP], matrix metalloproteinase-3 [MMP-3]), disease activity indices (Disease Activity in Psoriatic Arthritis [DAPSA], Disease Activity Score 28 joints [DAS28-CRP], Psoriatic Arthritis Screening and Evaluation [PASE], Psoriasis Area Severity Index [PASI]), radiographic damage (modified Total Sharp Score [mTSS]), and functional status (health assessment questionnaire [HAQ]), and axial involvement. RESULTS: Among 47 patients with PsA, 37 and 23 had US and clinical enthesitis, respectively. US and clinical enthesitis had very low concordance (kappa coefficient 0.04), with no correlation between enthesitis counts (r=0.15, p=0.30). The US enthesitis count correlated only with the MMP-3 level (r=0.41, p=0.007), whereas the clinical enthesitis count correlated with the DAPSA, DAS28-CRP, HAQ, and PASE (r=0.50, p<0.001; r=0.44, p=0.002; r=0.41, p=0.008; r=0.54, p<0.001, respectively). CONCLUSIONS: US and clinical enthesitis are completely different entities. US enthesitis, but not clinical enthesitis, reflects inflammatory conditions.

Soybean isoflavone can protect against osteoarthritis in ovariectomized rats.

Osteoarthritis (OA) is a chronic and incurable disease and a leading cause of significant pain and disability that is closely associated with aging and obesity. An appropriate long-term therapy regimen is presently unknown. An estrogen deficiency after menopause increases the incidence and severity of OA in women. Soybean isoflavone have weak estrogenic effects in several organs and have been considered as a potentially safe natural selective estrogen receptor modulator. The present study aimed to determine the effects of isoflavone on cartilage degradation in ovariectomized rats. Six-month-old female Sprague-Dawley (SD) rats (n = 40) were randomly assigned to sham operation (n = 10), ovariectomy (OVX) (n = 15) or OVX + isoflavone (OVXI) (n = 15) groups. The OVXI group was fed with soybean isoflavone (51.0 mg/kg/day) for nine weeks, then knee joints were excised. Cartilage degradation was evaluated by toluidine blue staining joint specimens, and by comparing values for serum C-telopeptides of Type II collagen (CTX-II) and cartilage oligomeric matrix protein (COMP) between baseline and the end of the study. Cartilage damage scored by Toluidine blue staining was significantly lower in the OXVI, than the OVX group (P < 0.016). The CTX-II values before the surgical procedure and the end of experiment, did not significantly differ among the groups. Values for COMP in all samples were below detection limits in all samples. Soy bean isoflavone limited the degeneration of cartilage induced by OVX in rats.

Do rheumatoid arthritis patients have low back pain or radiological lumbar lesions more frequently than the healthy population? - Cross-sectional analysis in a cohort study with age and sex-matched healthy volunteers.

BACKGROUND CONTEXT: Rheumatoid arthritis (RA) can affect the spine; however, the epidemiology of lumbar lesions and/or low back pain (LBP) in RA patients has not been well-studied. PURPOSE: The purpose of this study was to compare the prevalence of lumbar lesions and LBP in RA patients with that in healthy volunteers, and to elucidate the influence of RA on lumbar disease. STUDY DESIGN: Cross-sectional analysis in a cohort study with age- and sex-matched healthy volunteers. PATIENT SAMPLE: This study included 185 patients with RA and 188 gender/age-matched healthy volunteers without RA. OUTCOME MEASURES: Lumbar spondylolisthesis and prevalent vertebral fractures were evaluated using plain lateral X-ray images. Thoraco-lumbar scoliosis was evaluated using dual-energy X-ray absorptiometric images. LBP was assessed using the visual analogue scale (VAS) and Rolland-Morris disability questionnaire (RDQ). METHODS: The prevalence of radiological lumbar lesion and LBP was compared between the RA and control groups. In the RA group, factors associated with lumbar lesion and LBP were analyzed using a multiple logistic regression model. RESULTS: The prevalence rates of spondylolisthesis and prevalent vertebral fracture were significantly higher in the RA group than in the control group; the prevalence of thoraco-lumbar scoliosis tended to be higher in the RA group. There was no significant difference in the average LBP-VAS between the groups. However, the percentage of analgesic drug use was significantly higher, and RDQ scores tended to be worse in the RA group than the control group. Multivariate analysis revealed that age and disease activity score were both related to LBP in the RA group. CONCLUSIONS: RA patients are more likely to have radiological lumbar lesions. LBP in RA patients is well controlled, similar to the level in the healthy population; however, disease activity was related to LBP in RA patients. These results suggest that disease control is important for lumbar care in RA patients.

Comparison of median nerve stiffness with and without rheumatoid arthritis by ultrasound real-time tissue elastography: A propensity score matching study.

Objectives: This study aimed to compare median nerve stiffness measured by ultrasound real-time tissue elastography in patients with and without rheumatoid arthritis (RA and non-RA groups, respectively).Methods: Altogether, 402 hands of 201 RA group and 222 hands of 111 non-RA group were included in the study. Ultrasonography was performed to evaluate the circumference, cross-sectional area (CSA) and strain ratio as an elasticity of the median nerve at the inlet level of the carpal tunnel and the proximal portion of the carpal tunnel inlet. Using propensity score matching, the difference between RA and non-RA group were analyzed.Results: After propensity score matching, 135 hands in 104 RA group and 70 non-RA group were finally analyzed. There were no significant differences in the circumference and CSA of the median nerve between the two groups. The strain ratio of the median nerve was significantly higher in RA group than in non-RA group only at the inlet of the carpal tunnel level.Conclusions: The nerve stiffness in patients with RA measured by ultrasound real-time tissue elastography was higher than without RA. Inflammatory condition of the flexor tendon and wrist joint in patients with RA may generate fibrotic changes in the median nerve.Trial registration: University Hospital Medical Information Network Clinical Trials Registry: UMIN000015314.