Assessing joint destruction in the knees of patients with rheumatoid arthritis by using a semi-automated software for magnetic resonance imaging: therapeutic effect of methotrexate plus etanercept compared with methotrexate monotherapy.

OBJECTIVES: To evaluate the prevention of knee joint destruction and clinical efficacy of methotrexate (MTX) plus etanercept (ETN) compared with MTX monotherapy in patients with rheumatoid arthritis (RA) by using semi-automated software for magnetic resonance imaging (MRI) scan analysis. MATERIALS AND METHODS: This study enrolled patients with active moderate-to-severe RA who displayed an inadequate response to oral MTX at screening. Patients were assigned to receive either MTX plus ETN or MTX monotherapy (≥10 mg/week). The primary endpoint was the quantitative knee cartilage volume using our software developed for MRI scan analysis. RESULTS: A total of 18 female patients were enrolled in this study and allocated to the MTX + ETN group (n = 9) or the MTX monotherapy group (n = 9). At 52 weeks, the quantitative knee cartilage volume was significantly reduced compared with baseline in both groups (MTX plus ETN group: 2.3 ± 2.3 cm3; MTX monotherapy group: 2.4 ± 1.6 cm3); however, the difference was not significant. CONCLUSION: The semi-automated software for MRI scan analysis can reveal useful and potentially clinically important information about the characteristics of knee joint destruction in patients with RA.

The impact of joint disease on the Modified Health Assessment Questionnaire scores in rheumatoid arthritis patients: A cross-sectional study using the National Database of Rheumatic Diseases by iR-net in Japan.

OBJECTIVES: To investigate the effect of bilateral and unilateral joint disease on the Modified Health Assessment Questionnaire (MHAQ) scores and the differences in joint weighting in rheumatoid arthritis patients. METHODS: A total of 9212 subjects from the Japanese nationwide cohort database NinJa, 2011, were analyzed. The presence or absence of disease in each joint, including swelling and/or tenderness, was investigated. The correlations between bilateral and unilateral disease in each joint and MHAQ scores were investigated using multivariable logistic regression analysis. RESULTS: The patients' mean age and disease duration was 63.2 and 12.2 years, respectively. The Disease Activity Score-28 was 3.3. The odds ratios of physical impairment according to the MHAQ using multivariable logistic regression models for bilateral and unilateral joints, respectively, were: shoulder, 4.0 and 1.8; elbow, 2.6 and 1.8; wrist, 1.9 and 1.5; hip, 1.7 and 3.0; knee, 2.6 and 1.9; ankle, 2.3 and 2.0, finger, 1.4 and 1.2; and toe, 1.0 and 1.1. The shoulder, elbow, wrist, knee, and ankle had a significant effect on physical impairment. CONCLUSIONS: The MHAQ score was significantly affected by shoulder, elbow, wrist, knee, and ankle joint disease. Furthermore, bilateral disease tended to have a greater effect on physical impairment than unilateral disease.

Prevalence of total knee arthroplasty and its predictive factors in Japanese patients with rheumatoid arthritis: Analysis using the NinJa cohort.

OBJECTIVES: The aim of this study was to clarify the prevalence and the predictive factors for undergoing total knee arthroplasty (TKA) among patients with rheumatoid arthritis (RA). METHODS: The data of 1,134 patients with RA who were enrolled in the Japanese nationwide cohort database NinJa in 2003 and consecutively followed up until 2009 were analyzed. RESULTS: Seventy-six patients underwent TKA during the observation period. The yearly progression of the modified Health Assessment Questionnaire or mHAQ score from 2003 to 2004, but not the yearly progression of the Disease Activity Score in 28 Joints or DAS28 or patient visual analog scale (VAS) score, was significantly higher in the patients who underwent TKA than those who did not. Multivariate analysis showed that knee involvement in the disease, high Steinbrocker stage (III or IV), and high patient VAS score at the time of enrollment were powerful predictive factors, with hazard ratios of 4.01, 3.71, and 1.20, respectively. According to survival analysis with TKA as an endpoint, patients with knee involvement in the disease at the time of enrollment had a significantly worse 5-year survival rate than did those without knee involvement (83.5% vs. 97.0%, respectively). CONCLUSION: Several factors were elucidated as predictive factors for undergoing TKA among patients with RA.

Vertebral fractures affect functional status in postmenopausal rheumatoid arthritis patients.

Functional disability is a major concern in patients with rheumatoid arthritis (RA). This retrospective study investigated the risk factors for vertebral fractures (VFs) in postmenopausal RA patients and determined the impact of VFs on functional status. Data from a cohort of 200 postmenopausal RA patients in a single hospital registry were analyzed. Demographic and clinical data, imaging data from spine radiographs, and bone mineral density (BMD) data were collected from the patients at baseline and at the final visit (a mean of 2.9 years after the first visit). Risk factors for incident VFs and their impact on the modified health assessment questionnaire (mHAQ) were analyzed. Twenty-eight patients (14%) developed new VFs (NVFs). Logistic regression analysis adjusted for age, BMI, and disease duration revealed that daily dose of prednisolone, femoral neck BMD, use of active vitamin D3, and use of a bisphosphonate at baseline were factors associated with NVF, with odds ratios (95% confidence interval) of 1.27 (1.05-1.54), 0.94 (0.91-0.97), 0.34 (0.13-0.89), and 0.31 (0.12-0.82), respectively. Patients with NVF exhibited worse mHAQ scores and a greater increase in mHAQ scores from baseline compared with those without NVF. In conclusion, incident VFs were associated with reduced functional status in postmenopausal patients with RA. It is important to prevent VFs to maintain the functional status of RA patients.

Clinical characteristics of rheumatoid arthritis patients undergoing cervical spine surgery: an analysis of National Database of Rheumatic Diseases in Japan.

BACKGROUND: The aim of this study was to examine the clinical characteristics of rheumatoid arthritis (RA) patients who underwent cervical spine surgery using a multicenter observational database. METHODS: We obtained data from a nationwide observational cohort database of patients with rheumatic diseases (National Database of Rheumatic Diseases by iR-net in Japan (NinJa)) for the fiscal years 2003 to 2011. A total of 39 out of 60 patients who underwent cervical spine surgery for a RA-related cause and whose data were available for two consecutive years (to assess the preoperative patient status) were chosen as cases. Patients with a non-RA-related cause of surgery (e.g., trauma) were excluded. First, we compared the patient characteristics between the cases and total patients in the same fiscal year. Next, 106 eligible controls, who were defined as RA patients enrolled in the same fiscal year as the case subjects, who were matched for age, gender and disease duration (within ±1 year), were selected. We compared the demographic data between the two groups. We also calculated the percentage of patients who underwent cervical spine surgery (surgeries/total number of patients) in fiscal years 2003 to 2011. RESULTS: Although the proportion of patients using biologics linearly increased during study period, the percentage of patients undergoing cervical spine surgeries remained unchanged, at approximately 0.15%. These cases had more tender joints (3 vs. 1, p < 0.01) and exhibited a significantly higher Modified Health Assessment Questionnaire (MHAQ) score (1.13 vs. 0.5, p < 0.01), C-reactive protein (CRP) (1.5 vs. 0.36, p < 0.01), and disease activity score (DAS) 28-CRP (3.63 vs. 2.81, p < 0.01) compared to the controls. CONCLUSIONS: Our study revealed that RA patients requiring cervical spine surgery have a higher disease activity (as represented by the DAS28-CRP) and are more functionally disabled (as represented by the MHAQ) than control patients.

Midterm results of resection arthroplasty for forefoot deformities in patients with rheumatoid arthritis and the risk factors associated with patient dissatisfaction.

We investigated the midterm results of resection arthroplasty of all 5 metatarsal heads in patients with rheumatoid arthritis and forefoot deformity and analyzed the factors that affect patient satisfaction levels. Of 64 patients (1 male, 63 females), 107 feet were treated with resection arthroplasty for forefoot deformity at our hospital from January 1992 to December 2005. The mean follow-up period was 5.8 ± 3.1 years, with all patients having at least 1 year of follow-up. Of the 64 patients, 75% were satisfied with the surgery. The mean score for the postoperative Japanese Society for Surgery of the Foot lesser metatarsophalangeal-interphalangeal scale was 75.0 ± 15.8 points. Multivariate logistic regression analysis showed that patient-reported dissatisfaction was significantly associated with the recurrence of hammer toe deformity (odds ratio 2.66, 95% confidence interval 1.07 to 6.97), shortening of the resection arthroplasty space (odds ratio 0.85 for a 1-unit increase, 95% confidence interval 0.74 to 0.96), and the recurrence of hallux valgus (odds ratio 1.04 for a 1-unit increase, 95% confidence interval 1.00 to 1.09) during the postoperative period. From our results, interventions to prevent recurrence of hammer toe deformity, especially in toes with preoperative metatarsophalangeal joint dislocations, have been shown to be important in preventing complications and patient dissatisfaction after resection arthroplasty.

Normal sequential changes in neutrophil CD64 expression after total joint arthroplasty.

BACKGROUND: Neutrophil CD64 has been reported to be a sensitive and specific infection marker. Its measurement is thus considered to be useful in early diagnosis of post-operative periprosthetic infection. However, even its normal sequential changes after non-infectious total joint arthroplasty have remained ambiguous. Accordingly, we analyzed 2-week sequential neutrophil CD64 expression changes after total joint arthroplasty in order to clarify its normal postoperative kinetics. PATIENTS AND METHOD: From 41 patients who underwent primary total joint arthroplasties, peripheral blood samples were obtained at 1 day before (baseline) and 1, 3, 5, 7, and 14 days after surgery, and CD64 expression per cell was quantitatively measured. C-reactive protein (CRP) level, erythrocyte sedimentation rate (ESR) and white blood cell count (WBC) were simultaneously measured. RESULTS: No cases of postoperative local infection were observed. Levels of CD64 significantly elevated from day 1, peaked at day 3, and decreased significantly following day 5. Statistical analysis confirmed that significant differences existed between the baseline level and the levels at days 1 and 3, while no significant differences existed between the baseline level and those at days 5, 7 or 14. In 17 patients, CD64 peaked at over 2,000 molecules/cell, the level reported to be a cutoff value for distinguishing infection. Multiple regression analysis showed that the sole parameter of baseline CD64 level significantly explained the peak CD64 level. Postoperative CD64 peaks ranged from 1.6 to 2.7 times (median 1.9) the baseline levels. CRP, ESR and WBC also showed rapid elevations and all but WBC remained significantly higher than baseline at day 14. CONCLUSION: CD64 levels rise significantly, peaking within about 3 days following normal total joint arthroplasty, but decrease rapidly to near baseline within about 5 days. The data obtained can be expected to form a possible basis for early diagnosis of postoperative periprosthetic infection.

Analysis of the affected joints in rheumatoid arthritis patients in a large Japanese cohort.

OBJECTIVE: Rheumatoid arthritis (RA) is a chronic inflammatory disorder involving multiple joints. We investigated the distribution of the affected joints and the relationships among this distribution, the disease activity, and the disease duration in Japanese RA patients by cross-sectional analysis using the National Database of Rheumatic Diseases by iR-net in Japan. MATERIALS AND METHODS: A total of 6408 RA patients registered in the database were analyzed. In each patient, the location of joint swelling and joint tenderness of 68 joints was examined, and the relationships among the distribution of the affected joints, the disease activity as determined using the DAS28-ESR, and the disease duration were analyzed statistically. RESULTS: For the 6408 RA patients examined, the wrist was the most frequently affected site. There were some differences in the prevalence of tenderness and swelling; tenderness was frequently observed in large joints such as the knee, elbow and shoulder, while swelling was frequently observed in small joints such as the metacarpophalangeal joints. Although the frequency of involvement increased in all joints as disease activity increased, the pattern of distribution was not affected by disease activity. Furthermore, the distribution was not influenced by disease duration. CONCLUSIONS: Based on the results of this study, we can draw the following conclusions: (1) the wrist was the most affected joint; (2) there was a discrepancy between the distribution of swollen joints and that of tender joints; and (3) the distribution of affected joints was uniform regardless of disease activity.

Comparison of composite disease activity indices for rheumatoid arthritis.

To evaluate the composite disease activity indices for rheumatoid arthritis (RA), we compared disease activities and the changes therein calculated using the Disease Activity Score based on 28 joint counts using erythrocyte sedimentation rate (DAS28-ESR), DAS28-CRP (C-reactive protein), Simplified Disease Activity Index (SDAI), and Clinical Disease Activity Index (CDAI) in a cohort of 1,412 patients with RA. The median (1st; 3rd quartile) scores were 4.20 (3.31; 5.14) for DAS28-ESR, 3.44 (2.59; 4.36) for DAS28-CRP, 13.6 (7.49; 21.1) for SDAI, and 12.0 (6.9; 18.9) for CDAI. Absolute scores and their changes were significantly correlated (p < 0.0001) in all combinations among these four disease activity indices; however, their correlations were lower in males than in females. Correlations between disease activity indices and the clinical and acute phase reactant variables were different according to disease activity index, sex and age. A comparison of the number of patients in each disease activity category according to the disease activity indices using kappa-statistics revealed an almost perfect agreement between SDAI and CDAI (κ = 0.871), a moderate agreement between DAS28-ESR and SDAI (κ = 0.415) or CDAI (κ = 0.427), but only fair agreement between DAS28-ESR and DAS28-CRP (κ = 0.329). For the selection of a disease activity index for an evaluation of RA patients, both the convenience and the characteristics of the respective disease activity index should be considered.

Efficacy and safety of single-dose mizoribine for patients with rheumatoid arthritis: results at 6 months after switching from a multiple-dose regimen without a change in total daily dose.

To determine the efficacy and safety of single-dose mizoribine (MZR) for patients with rheumatoid arthritis (RA), a 6-month, single-arm, open-label, prospective observation study was performed. In patients who had been taking MZR at 100-150 mg/day in 2-3 divided portions continuously for at least 3 months, and who had shown a lack of clinical response, or escape (defined as a lack of response at the time of switching, even if some form of response had been shown before that), multiple-dose administration was switched to single-dose administration without changing the total daily dose. Efficacy was assessed in terms of the disease activity score, using the 28-joint count and erythrocyte sedimentation rate (DAS 28-ESR). Of the 34 enrolled patients, 28 met all the eligibility criteria and were assessed for efficacy, and finally 26 patients were able to receive the single-dose regimen throughout the full 6 months. The DAS28-ESR showed a significant decrease from 2 months after switching, and 46.4% of the 28 patients finally achieved a good or moderate response (3 and 10 patients, respectively). With regard to safety, no serious adverse events were observed. In conclusion, the administration of MZR at 100 or 150 mg in a single dose is thought to be a useful alternative form of MZR therapy.

Recent trends in orthopedic surgery performed in Japan for rheumatoid arthritis.

The aim of this report was to review the use of orthopedic surgeries performed to manage rheumatoid arthritis (RA). Our review of studies published in English indicates that there has been a decrease in RA-associated surgeries in Western countries. Improvements in medical treatment may partly explain the reduction in numbers of orthopedic joint surgeries, which also suggests a worldwide trend toward improved long-term outcomes. However, the results of our multicenter study in Japan indicate that the number of RA-associated operations has not decreased, and that the numbers of operations performed annually have been relatively stable from 1998 to 2008. Although there definitely has been a decline in the numbers of synovectomy surgeries, the numbers of operations on the upper limbs and foot arthroplasties have increased. With the trend toward milder disease because of improved medical treatment, we speculate that RA patients may want and need better function for the activities of daily living. The combination of medical treatment and surgical intervention is thought to improve outcomes in RA patients who will develop joint destruction. Additional studies, including analyses of RA databases containing long-term data on a variety of surgical interventions, are needed.

The usefulness of neutrophil CD64 expression in the diagnosis of local infection in patients with rheumatoid arthritis in daily practice.

BACKGROUND: The diagnosis of local infection in patients with rheumatoid arthritis (RA) is frequently difficult because clinical signs and symptoms and laboratory test results of local infection are also observed in arthritis of active RA. The need for a specific marker of infection is high in RA patients. The usefulness of neutrophil CD64 expression (CD64) to diagnose local musculoskeletal infection (local infection) and discriminate local infection from RA-related inflammation in RA patients was examined. METHODS: CD64 was measured by a quantitative method using flow cytometry in 61 RA patients in whom local infection was suspected, and the usefulness of CD64 was examined by comparing the findings with clinical results. RESULTS: There were 25 patients with local infection and 36 patients without infection. The median CD64 value the patients with local infection was 3148 molecules/cell (interquartile range [IQR], 2140-6231) and that of the patients without infection was 1106 molecules/cell (IQR, 804-1464) with a statistically significant difference (P < 0.0001). In contrast, no significant difference between the groups was observed in C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and white blood cell (WBC) count. The area under the curve of CD64 calculated by receiver operating characteristic curve analysis was larger than that of CRP, ESR, or WBC count, suggesting that CD64 has superior ability to discriminate of infection compared to these other markers. When the cutoff value of CD64 was set at 2000 molecules/cell, the sensitivity and specificity of CD64 for the detection of local infection in RA patients were 76.0% and 94.4%, respectively. CONCLUSIONS: CD64 is a useful marker in RA patients to discriminate local infection from RA-related inflammation.

Impact of biologics on the prevalence of orthopedic surgery in the National Database of Rheumatic Diseases in Japan.

The aim of this study was to investigate changes in the treatment strategy of rheumatoid arthritis (RA) and the prevalence of RA-related surgeries after approval of biologics in Japan and to analyze the impact of biologics on the incidence of orthopedic surgeries using a nationwide observational cohort database of rheumatic diseases [National Database of Rheumatic Diseases by iR-net in Japan (NinJa)]. The proportion of patients using biologics linearly increased from 2004 (1.8%) to 2007 (10.0%), but neither the number nor type of RA-related surgery significantly changed during this period. Patients treated with biologics exhibited relatively more severe disease activity and lower physical function. Among patients using biologics, those who underwent RA-related surgeries exhibited background characteristics of longer disease duration and worse physical function, while disease activity was not different from patients without surgery. These results suggest that the potential value of biologics in avoiding surgical procedure is limited in patients with severe functional disorders caused by long disease duration. Further investigation with a longer observation period is required to obtain more definite conclusions as to the impact of biologics usage on orthopedic surgeries.

Neutrophil CD64 expression as a diagnostic marker for local infection and crystal-induced arthritis.

The usefulness of neutrophil CD64 expression was examined in diagnosing local infection, including soft tissue, bone, and joint infections. Among 99 patients suspected of local infection, 31 were confirmed and 68 patients were not. The CD64 level of patients with local infection was significantly higher than in those without infection [4,193 ± 1,132 vs. 1,017 ± 59 molecules/cell (mean ± standard deviation); p < 0.001]. The area under the curve of CD64 calculated by receiver operating characteristic curve analysis was larger than that of C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), or white blood cell (WBC) count. In addition, CD64 levels of patients with crystal-induced arthritis remained within cutoff value (2,000 molecules/cell). These data suggest that measuring CD64 expression can be a useful diagnostic marker for local musculoskeletal infection and crystal-induced arthritis.

A Proposal to Standardize Low Disease Activity Criteria in Rheumatoid Arthritis Based on the Outcome Measures in Rheumatology Minimal Disease Activity Definition.

OBJECTIVE: We aimed to standardize the definition of low disease activity in rheumatoid arthritis (RA) using the Outcome Measures in Rheumatology (OMERACT) group's proposed definition of minimal disease activity. METHOD: Based on a nationwide RA database, we proposed new Boolean low disease activity criteria using OMERACT's core set definition of minimal disease activity that requires the fulfillment of at least five of the following seven core set measures: a pain score of 2 or less, a swollen joint count (SJC28) of 1 or fewer, a tender joint count of 1 or fewer, a Health Assessment Questionnaire score of 0.5 or less, a Physician's Global Assessment score of 1.5 or less, a Patient's Global Assessment score of 2 or less, and an erythrocyte sedimentation rate (ESR) of 20 mm/h or less. Using receiver operating characteristic analysis, we determined the cutoffs for the Simplified Disease Activity Index (SDAI), Clinical Disease Activity Index (CDAI), Routine Assessment of Patient Index Data 3 (RAPID3), and the Disease Activity Score in 28 joints (DAS28)-ESR. RESULTS: Of 8298 patients, 56.2% met the proposed Boolean low disease activity criteria. We determined an SDAI score of 5.5 or less and a CDAI score of 5 or less to be the new cutoffs, and we chose a DAS28 of 2.85 or less (the original cutoff for DAS-based minimal disease activity) and a RAPID3 score of 6 or less (the original cutoff for RAPID3-based low disease activity) with or without a swollen joint count (SJC) (SJC of 2 or fewer) as the cutoffs for DAS28 and RAPID3. The agreement between the new cutoffs for DAS28 of 2.85 or less vs. CDAI score of 5 or less, CDAI score of 5 or less vs. RAPID3 score of 6 or less (with SJC of 2 or fewer), and DAS28 of 2.85 or less vs. RAPID3 score of 6 or less (with SJC of 2 or fewer), was 0.619, 0.612 (0.702), and 0.474 (0.531), respectively. CONCLUSION: OMERACT's minimal disease activity definition may be used to standardize the criteria for low disease activity.

Rheumatoid arthritis associated with osteopetrosis.

Osteopetrosis is an inherited disorder characterized by reduced bone resorption. We here report a rare case of osteopetrosis associated with rheumatoid arthritis. The patient was diagnosed as autosomal dominant osteopetrosis type II in his youth and developed rheumatoid arthritis at 42 years of age. In spite of the severe inflammation and rapid progression of cartilage destruction, the progression of bone erosion was slow in this patient.

Prophylactic effect of sulfasalazine against Pneumocystis pneumonia in patients with rheumatoid arthritis: A nested case-control study.

OBJECTIVES: To evaluate the prophylactic effect of sulfasalazine against Pneumocystis jirovecii pneumonia (PJP) among rheumatoid arthritis (RA) patients. METHODS: We used a nationwide Japanese multicenter RA database to extract data from 2005 and 2014. To identify PJP cases, we selected patients hospitalized for PJP and verified their diagnosis. Two control groups, one unmatched and the other matched for age, sex, glucocorticoid, methotrexate, and tacrolimus dosage, and the use (and type, if used) of biological disease-modifying antirheumatic drug were selected by incidence-density sampling. The odds ratios for PJP associated with sulfasalazine use and other clinical factors were estimated by exact and standard conditional logistic regression. RESULTS: From 18,668 participants, 60 cases, 356 unmatched controls, and 337 matched controls were selected. None of the cases received sulfasalazine before PJP onset. A comparison of the cases with the unmatched controls showed that sulfasalazine use carried a decreased risk of PJP (adjusted odds ratio 0.18, 95% confidence interval 0.00-0.92). A comparison of the cases and matched controls also showed that sulfasalazine use had a decreased risk of PJP (0.08, 0.00-0.36). In an analysis of the cases and unmatched controls who did not receive sulfasalazine, an increased risk of PJP was associated with lung disease (3.88, 1.89-7.95) and the use of glucocorticoid (5.71, 2.68-12.19), methotrexate (5.25, 2.01-13.74), and tumor necrosis factor inhibitors (2.32, 1.10-4.93). CONCLUSIONS: The results of this nested case-control study demonstrated the preventive effect of sulfasalazine against PJP. The results await confirmation by future prospective studies.

Influence of large joint involvement on patient-physician discordance in global assessment of rheumatoid arthritis disease activity analyzed by a novel joint index.

OBJECTIVES: The discordance between patient global assessment (PGA) and physician global assessment (PhGA) of rheumatoid arthritis (RA) disease activity may be problematic in clinical practice. The aim of this study was to identify determinants of this discordance using a nationwide RA database in Japan (NinJa) with special attention to large joint involvement. METHODS: We investigated 12 043 adults with RA and used a discordance cutoff of 3 cm. Large joint involvement was investigated using novel joint indices (x, y, z), where x and y were the indices for upper and lower joints, respectively, and z was for large joint predominance. Predictors of PGA-PhGA discordance and determinants of PGA and PhGA were analyzed by multivariate logistic and linear regression models, respectively. RESULTS: Multivariate logistic regression identified age, pain and high modified Health Assessment Questionnaire score as predictors of positive discordance (PGA ≥ PhGA), whereas parameters of disease activity in RA (C-reactive protein, x and y), class 3-4 functional status, and z were found to predict against positive discordance. Linear regression analysis revealed that PGA was mainly determined by pain, whereas PhGA was determined by various other factors. CONCLUSIONS: RA care providers should focus on pain and functional disability to decrease PGA-PhGA discordance. High disease activity and large joint involvement decreased PGA-PhGA discordance, indicating that the number and distribution of affected joints influenced the perception of disease activity by patients with RA and their physicians.

Impact of the size and number of swollen joints on serum C-reactive protein level and erythrocyte sedimentation rate in rheumatoid arthritis: a cross-sectional study in Japan.

No studies have yet reported the influence of swelling in individual joints on serum C-reactive protein and erythrocyte sedimentation rate. To examine this association, we used data from the NinJa registry, the largest registry of rheumatoid arthritis patients in Japan. Sixty-six palpable joints were categorized by size into three groups (small, medium-sized, and knees) with surface area cutoffs of 10 and 100 cm2. Of 10,720 cases registered in NinJa in 2012, 8444 cases with either no swollen joints or swelling limited to one joint-size category were analyzed. Groups with larger numbers of swollen joints showed higher levels of both markers in each joint-size category. Groups with larger swollen joints had higher levels of both markers compared with groups with the same number of (smaller) swollen joints. Linear regression revealed that the increments of C-reactive protein (mg/dL/joint) and erythrocyte sedimentation rate (mm/1 h/joint) were 0.056 and 0.89, 0.24 and 5.0, and 0.46 and 8.9 for small and medium-sized joints and knee joints, respectively. The levels of systemic inflammation markers increased with the involvement of larger and/or more joints. These results were successfully illustrated by the use of large-scale data, which eliminated wide intragroup scattering of the marker values.

Trends in Treatment, Outcomes, and Incidence of Orthopedic Surgery in Patients with Rheumatoid Arthritis: An Observational Cohort Study Using the Japanese National Database of Rheumatic Diseases.

OBJECTIVE: In this study, we investigated the changes in clinical outcome, treatment, and incidence of orthopedic surgery in patients with rheumatoid arthritis (RA) from 2004 to 2014. METHODS: Data were studied from the Japanese nationwide cohort database, NinJa (National Database of Rheumatic Diseases by iR-net in Japan), from 2004 to 2014. The time trends in the incidence of orthopedic procedures were analyzed using linear regression analysis. The cross-sectional annual data were compared between 2004 and 2014 to analyze the changes in clinical outcome and treatment. RESULTS: The incidence of orthopedic surgeries in patients with RA consistently decreased from 72.2 procedures per 1000 patients in 2004 to 51.5 procedures per 1000 patients in 2014 (regression coefficient = -0.0028, 95% CI -0.0038 to -0.0019, p < 0.001). The greatest reduction was found in total knee arthroplasty and total hip arthroplasty. Disease activity and functional disability improved significantly over this decade. The proportions of patients receiving methotrexate and biologic disease-modifying antirheumatic drugs significantly increased from 39.6% and 1.7% in 2004 to 63.8% and 27.4% in 2014, respectively. CONCLUSION: The overall incidence of orthopedic surgeries in patients with RA significantly decreased, accompanied by improved clinical outcomes because of the expanded use of effective drugs; however, the declining trend differed between procedures or locations. The results from the present study suggest that there might be a change in supply and demand for orthopedic surgeries.