Edward H. Giannini

Estimates of the prevalence of arthritis and selected musculoskeletal disorders in the United States

OBJECTIVE To provide a single source for the best available estimates of the national prevalence of arthritis in general and of selected musculoskeletal disorders (osteoarthritis, rheumatoid arthritis, juvenile rheumatoid arthritis, the spondylarthropathies, systemic lupus erythematosus, scleroderma, polymyalgia rheumatica/giant cell arteritis, gout, fibromyalgia, and low back pain). METHODS The National Arthritis Data Workgroup reviewed data from available surveys, such as the National Health and Nutrition Examination Survey series. For overall national estimates, we used surveys based on representative samples. Because data based on national population samples are unavailable for most specific musculoskeletal conditions, we derived data from various smaller survey samples from defined populations. Prevalence estimates from these surveys were linked to 1990 US Bureau of the Census population data to calculate national estimates. We also estimated the expected frequency of arthritis in the year 2020. RESULTS Current national estimates are provided, with important caveats regarding their interpretation, for self-reported arthritis and selected conditions. An estimated 15% (40 million) of Americans had some form of arthritis in 1995. By the year 2020, an estimated 18.2% (59.4 million) will be affected. CONCLUSION Given the limitations of the data on which they are based, this report provides the best available prevalence estimates for arthritis and other rheumatic conditions overall, and for selected musculoskeletal disorders, in the US population.

Etanercept in children with polyarticular juvenile rheumatoid arthritis

BACKGROUND We evaluated the safety and efficacy of etanercept, a soluble tumor necrosis factor receptor (p75):Fc fusion protein, in children with polyarticular juvenile rheumatoid arthritis who did not tolerate or had an inadequate response to methotrexate. METHODS Patients 4 to 17 years old received 0.4 mg of etanercept per kilogram of body weight subcutaneously twice weekly for up to three months in the initial, open-label part of a multicenter trial. Those who responded to treatment then entered a double-blind study and were randomly assigned to receive either placebo or etanercept for four months or until a flare of the disease occurred. A response was defined as an improvement of 30 percent or more in at least three of six indicators of disease activity, with no more than one indicator worsening by more than 30 percent. RESULTS At the end of the open-label study, 51 of the 69 patients (74 percent) had had responses to etanercept treatment. In the double-blind study, 21 of the 26 patients who received placebo (81 percent) withdrew because of disease flare, as compared with 7 of the 25 patients who received etanercept (28 percent) (P=0.003). The median time to disease flare with placebo was 28 days, as compared with more than 116 days with etanercept (P<0.001). In the double-blind study, there were no significant differences between the two treatment groups in the frequency of adverse events. CONCLUSIONS Treatment with etanercept leads to significant improvement in patients with active polyarticular juvenile rheumatoid arthritis. Etanercept is well tolerated by pediatric patients.

Methotrexate in resistant juvenile rheumatoid arthritis : results of the U.S.A.-U.S.S.R. double-blind, placebo-controlled trial

BACKGROUND The antimetabolite methotrexate has been shown in placebo-controlled trials to be effective in adults with rheumatoid arthritis. Methotrexate may also be effective in children with resistant juvenile rheumatoid arthritis, but the supporting data are from uncontrolled trials. METHODS Centers in the United States and the Soviet Union participated in this randomized, controlled, double-blind trial designed to evaluate the effectiveness and safety of orally administered methotrexate. Patients received one of the following treatments each week for six months: 10 mg of methotrexate per square meter of body-surface area (low dose), 5 mg of methotrexate per square meter (very low dose), or placebo. The use of prednisone (less than or equal to 10 mg per day) and two nonsteroidal antiinflammatory drugs was also allowed. RESULTS The 127 children (mean age, 10.1 years) had a mean duration of disease of 5.1 years; 114 qualified for the analysis of efficacy. According to a composite index of several response variables, 63 percent of the children who received low-dose methotrexate improved, as compared with 32 percent of those in the very-low-dose group and 36 percent of those in the placebo group (P = 0.013). As compared with the placebo group, the low-dose group also had significantly larger mean reductions from base line in the number of joints with pain on motion (-11.0 vs. -7.1), the pain-severity score (-19 vs. -11.5), the number of joints with limited motion (-5.4 vs. -0.7), and the erythrocyte sedimentation rate (-19.0 vs. -6 mm per hour). In the methotrexate groups only three children had the drug discontinued because of mild-to-moderate side effects; none had severe toxicity. CONCLUSIONS Methotrexate given weekly in low doses is an effective treatment for children with resistant juvenile rheumatoid arthritis, and at least in the short term this regimen is safe.

Adalimumab with or without Methotrexate in Juvenile Rheumatoid Arthritis

BACKGROUND Tumor necrosis factor (TNF) has a pathogenic role in juvenile rheumatoid arthritis. We evaluated the efficacy and safety of adalimumab, a fully human monoclonal anti-TNF antibody, in children with polyarticular-course juvenile rheumatoid arthritis. METHODS Patients 4 to 17 years of age with active juvenile rheumatoid arthritis who had previously received treatment with nonsteroidal antiinflammatory drugs underwent stratification according to methotrexate use and received 24 mg of adalimumab per square meter of body-surface area (maximum dose, 40 mg) subcutaneously every other week for 16 weeks. We randomly assigned patients with an American College of Rheumatology Pediatric 30% (ACR Pedi 30) response at week 16 to receive adalimumab or placebo in a double-blind fashion every other week for up to 32 weeks. RESULTS Seventy-four percent of patients not receiving methotrexate (64 of 86) and 94% of those receiving methotrexate (80 of 85) had an ACR Pedi 30 response at week 16 and were eligible for double-blind treatment. Among patients not receiving methotrexate, disease flares (the primary outcome) occurred in 43% of those receiving adalimumab and 71% of those receiving placebo (P=0.03). Among patients receiving methotrexate, flares occurred in 37% of those receiving adalimumab and 65% of those receiving placebo (P=0.02). At 48 weeks, the percentages of patients treated with methotrexate who had ACR Pedi 30, 50, 70, or 90 responses were significantly greater for those receiving adalimumab than for those receiving placebo; the differences between patients not treated with methotrexate who received adalimumab and those who received placebo were not significant. Response rates were sustained after 104 weeks of treatment. Serious adverse events possibly related to adalimumab occurred in 14 patients. CONCLUSIONS Adalimumab therapy seems to be an efficacious option for the treatment of children with juvenile rheumatoid arthritis. (ClinicalTrials.gov number, NCT00048542.)

Abatacept in children with juvenile idiopathic arthritis: a randomised, double-blind, placebo-controlled withdrawal trial

BACKGROUND Some children with juvenile idiopathic arthritis either do not respond, or are intolerant to, treatment with disease-modifying antirheumatic drugs, including anti-tumour necrosis factor (TNF) drugs. We aimed to assess the safety and efficacy of abatacept, a selective T-cell costimulation modulator, in children with juvenile idiopathic arthritis who had failed previous treatments. METHODS We did a double-blind, randomised controlled withdrawal trial between February, 2004, and June, 2006. We enrolled 190 patients aged 6-17 years, from 45 centres, who had a history of active juvenile idiopathic arthritis; at least five active joints; and an inadequate response to, or intolerance to, at least one disease-modifying antirheumatic drug. All 190 patients were given 10 mg/kg of abatacept intravenously in the open-label period of 4 months. Of the 170 patients who completed this lead-in course, 47 did not respond to the treatment according to predefined American College of Rheumatology (ACR) paediatric criteria and were excluded. Of the patients who did respond to abatacept, 60 were randomly assigned to receive 10 mg/kg of abatacept at 28-day intervals for 6 months, or until a flare of the arthritis, and 62 were randomly assigned to receive placebo at the same dose and timing. The primary endpoint was time to flare of arthritis. Flare was defined as worsening of 30% or more in at least three of six core variables, with at least 30% improvement in no more than one variable. We analysed all patients who were treated as per protocol. This trial is registered, number NCT00095173. FINDINGS Flares of arthritis occurred in 33 of 62 (53%) patients who were given placebo and 12 of 60 (20%) abatacept patients during the double-blind treatment (p=0.0003). Median time to flare of arthritis was 6 months for patients given placebo (insufficient events to calculate IQR); insufficient events had occurred in the abatacept group for median time to flare to be assessed (p=0.0002). The risk of flare in patients who continued abatacept was less than a third of that for controls during that double-blind period (hazard ratio 0.31, 95% CI 0.16-0.95). During the double-blind period, the frequency of adverse events did not differ in the two treatment groups. Adverse events were recorded in 37 abatacept recipients (62%) and 34 (55%) placebo recipients (p=0.47); only two serious adverse events were reported, both in controls (p=0.50). INTERPRETATION Selective modulation of T-cell costimulation with abatacept is a rational alternative treatment for children with juvenile idiopathic arthritis. FUNDING Bristol-Myers Squibb.

Safety and Efficacy of up to Eight Years of Continuous Etanercept Therapy in Patients With Juvenile Rheumatoid Arthritis

OBJECTIVE To evaluate the safety and efficacy of up to 8 years of etanercept treatment in patients with polyarticular-course juvenile rheumatoid arthritis (JRA). METHODS Patients with JRA who previously participated in a randomized controlled trial (RCT) of etanercept were eligible to receive etanercept in a long-term open-label extension (OLE) trial. Safety end points included the incidences of serious adverse events (SAEs), medically important infections (MIIs), and death. Efficacy end points included the American College of Rheumatology (ACR) Pediatric 30 (Pedi 30), Pedi 50, Pedi 70, Pedi 90, and Pedi 100 criteria for improvement. RESULTS Of the 69 patients originally enrolled in the RCT, 58 (84%) participated in the OLE, for a total of 318 patient-years of etanercept exposure. A total of 42 of the 58 patients (72%) entered the fourth year of continuous etanercept treatment, and 26 patients (45%) entered the eighth year. Sixteen patients (23% of those entering the RCT) reported 39 SAEs. The overall rate of SAEs (0.12 per patient-year) did not increase with long-term exposure to etanercept. The rate of MIIs (0.03 per patient-year) remained low; 1 new MII was reported in patients with > or =5 years of etanercept exposure. No cases of tuberculosis, opportunistic infections, malignancies, lymphomas, lupus, demyelinating disorders, or deaths were reported. An ACR Pedi 70 response or higher was achieved by 100% of patients with 8 years of data (11 of 11) and by 61% of patients according to the last observation carried forward data (28 of 46). CONCLUSION These data suggest that the acceptable safety profile of etanercept therapy is maintained for up to 8 years in this population of JRA patients. Improvements in the signs and symptoms of JRA were also maintained for up to 8 years.

Methotrexate in Resistant Juvenile Rheumatoid Arthritis

BACKGROUND The antimetabolite methotrexate has been shown in placebo-controlled trials to be effective in adults with rheumatoid arthritis. Methotrexate may also be effective in children with resistant juvenile rheumatoid arthritis, but the supporting data are from uncontrolled trials. METHODS Centers in the United States and the Soviet Union participated in this randomized, controlled, double-blind trial designed to evaluate the effectiveness and safety of orally administered methotrexate. Patients received one of the following treatments each week for six months: 10 mg of methotrexate per square meter of body-surface area (low dose), 5 mg of methotrexate per square meter (very low dose), or placebo. The use of prednisone (less than or equal to 10 mg per day) and two nonsteroidal antiinflammatory drugs was also allowed. RESULTS The 127 children (mean age, 10.1 years) had a mean duration of disease of 5.1 years; 114 qualified for the analysis of efficacy. According to a composite index of several response variables, 63 percent of the children who received low-dose methotrexate improved, as compared with 32 percent of those in the very-low-dose group and 36 percent of those in the placebo group (P = 0.013). As compared with the placebo group, the low-dose group also had significantly larger mean reductions from base line in the number of joints with pain on motion (-11.0 vs. -7.1), the pain-severity score (-19 vs. -11.5), the number of joints with limited motion (-5.4 vs. -0.7), and the erythrocyte sedimentation rate (-19.0 vs. -6 mm per hour). In the methotrexate groups only three children had the drug discontinued because of mild-to-moderate side effects; none had severe toxicity. CONCLUSIONS Methotrexate given weekly in low doses is an effective treatment for children with resistant juvenile rheumatoid arthritis, and at least in the short term this regimen is safe.

American College of Rheumatology provisional criteria for defining clinical inactive disease in select categories of juvenile idiopathic arthritis

To prospectively validate the preliminary criteria for clinical inactive disease (CID) in patients with select categories of juvenile idiopathic arthritis (JIA).

Development of validated disease activity and damage indices for the juvenile idiopathic inflammatory myopathies: II. The childhood myositis assessment scale (CMAS): a quantitative tool for the evaluation of muscle function

OBJECTIVE To develop, validate, and determine the measurement characteristics of a quantitative tool for assessing the severity of muscle involvement in children with idiopathic inflammatory myopathies. METHODS The Childhood Myositis Assessment Scale (CMAS) was developed from 2 existing observational functional assessment tools to assess muscle function in the areas of strength and endurance across a wide range of ability and ages. The 14 ordinal items included were chosen to assess primarily axial and proximal muscle groups and are ranked with standard performance and scoring methods. Following the development of the CMAS, a training video and written instructions were developed and reviewed by the physicians participating in this study. Subsequently, utilizing a randomized block design, 12 physicians independently scored 10 children (9 with dermatomyositis, 1 with polymyositis; ages 4-15 years) twice in one day (morning and afternoon) on the CMAS. A pediatric physical therapist performed quantitative manual muscle strength testing (MMT) twice on each child (morning and afternoon), including the neck, trunk, and proximal and distal extremity muscle groups. RESULTS The CMAS has a potential range of 0-51, with higher scores indicating greater muscle strength and endurance. The observed mean for the 10 patients was 36.4 (median 44, SD 14.1, observed range 5-51). The total score for the CMAS correlated with the physicians global assessment (by visual analog scale) of disease activity, the MMT score, serum creatine kinase level, and the Juvenile Arthritis Functional Assessment Report score. The score on the CMAS was not correlated with patient age. Interrater reliability (Kendalls coefficient of concordance) ranged from 0.77 to 1.0 for individual items (all P < 0.001), and overall, it was 0.95 (P < 0.001). Intrarater reliability for the individual physicians was measured by correlation of the CMAS scores for each patient on 2 separate evaluations and ranged from 0.97 to 0.99, with an overall correlation for all physicians of 0.98 (all P < 0.001). CONCLUSION The CMAS demonstrated an acceptable range of observed scores, excellent convergent validity, and excellent inter- and intrarater reliability. The CMAS is validated to quantitatively assess muscle function in the areas of strength and endurance in children with idiopathic inflammatory myopathies. It can be used in routine clinical care as well as therapeutic trials.

Natural killer cell dysfunction is a distinguishing feature of systemic onset juvenile rheumatoid arthritis and macrophage activation syndrome

Macrophage activation syndrome (MAS) has been reported in association with many rheumatic diseases, most commonly in systemic juvenile rheumatoid arthritis (sJRA). Clinically, MAS is similar to hemophagocytic lymphohistiocytosis (HLH), a genetic disorder with absent or depressed natural killer (NK) function. We have previously reported that, as in HLH, patients with MAS have profoundly decreased NK activity, suggesting that this abnormality might be relevant to the pathogenesis of the syndrome. Here we examined the extent of NK dysfunction across the spectrum of diseases that comprise juvenile rheumatoid arthritis (JRA). Peripheral blood mononuclear cells (PBMC) were collected from patients with pauciarticular (n = 4), polyarticular (n = 16), and systemic (n = 20) forms of JRA. NK cytolytic activity was measured after co-incubation of PBMC with the NK-sensitive K562 cell line. NK cells (CD56+/T cell receptor [TCR]-αβ-), NK T cells (CD56+/TCR-αβ+), and CD8+ T cells were also assessed for perforin and granzyme B expression by flow cytometry. Overall, NK cytolytic activity was significantly lower in patients with sJRA than in other JRA patients and controls. In a subgroup of patients with predominantly sJRA, NK cell activity was profoundly decreased: in 10 of 20 patients with sJRA and in only 1 of 20 patients with other JRA, levels of NK activity were below two standard deviations of pediatric controls (P = 0.002). Some decrease in perforin expression in NK cells and cytotoxic T lymphocytes was seen in patients within each of the JRA groups with no statistically significant differences. There was a profound decrease in the proportion of circulating CD56bright NK cells in three sJRA patients, a pattern similar to that previously observed in MAS and HLH. In conclusion, a subgroup of patients with JRA who have not yet had an episode of MAS showed decreased NK function and an absence of circulating CD56bright population, similar to the abnormalities observed in patients with MAS and HLH. This phenomenon was particularly common in the systemic form of JRA, a clinical entity strongly associated with MAS.