OARSI-OMERACT initiative: defining thresholds for symptomatic severity and structural changes in disease modifying osteoarthritis drug (DMOAD) clinical trials.

OBJECTIVE: Total joint replacement has been proposed as an endpoint in disease modifying osteoarthritis drug (DMOAD) randomized clinical trials (RCTs); however, disparities have generated concerns regarding this outcome. A combined Osteoarthritis Research Society International (OARSI)/Outcome Measures in Rheumatology (OMERACT) initiative was launched in 2004 to develop a composite index ['virtual total joint replacement' (VJR)] as a surrogate outcome for osteoarthritis (OA) progression in DMOAD RCTs. Our objective was to evaluate the prevalence of patients fulfilling different thresholds of sustained pain, reduced function, and X-ray change in existing DMOAD RCTs. DESIGN: Post hoc analysis of summary data from the placebo arm of eight DMOAD RCTs. RESULTS: Eight OA RCTs representing 1379 patients were included. Pain was assessed by WOMAC and/or VAS and function by WOMAC and/or Lequesne. Among six knee and two hip studies, 248 (22%) and 132 (51%) patients respectively had X-ray progression [decrease joint space width (JSW) ≥0.5 mm]. The prevalence of patients fulfilling clinical and radiographic criteria was highest (n = 163, 12%) in the least stringent scenario (pain + function ≥80 at ≥2 visits); with few patients (n = 129, 2%) in the most stringent scenario (pain + function ≥80 at ≥4 visits). Using these prevalence data, a sample size of 352-2144 per group would be needed to demonstrate a 50% difference between groups. CONCLUSIONS: The prevalence of patients with sustained symptomatic OA of at least a moderate degree with X-ray progression is low. Even using lenient criteria to define VJR, large patient numbers would be required to detect differences between groups in DMOAD RCTs. Investigation of the optimal cutoff threshold and combination of symptoms and radiographic change should be pursued.

The human pharmacokinetics of oral ingestion of glucosamine and chondroitin sulfate taken separately or in combination.

OBJECTIVE: As part of the National Institutes of Health (NIH)-sponsored Glucosamine/Chondroitin sulfate Arthritis Intervention Trial (GAIT) our objective here was to examine (1) the pharmacokinetics (PK) of glucosamine (GlcN) and chondroitin sulfate (CS) when taken separately or in combination as a single dose in normal individuals (n=29) and (2) the PK of GlcN and CS when taken as a single dose after 3 months daily dosing with GlcN, CS or GlcN+CS, in patients with symptomatic knee pain (n=28). METHODS: The concentration of GlcN in the circulation was determined by established fluorophore-assisted carbohydrate electrophoresis (FACE) methods. The hydrodynamic size and disaccharide composition of CS chains in the circulation and dosage samples was determined by Superose 6 chromatography and FACE. RESULTS: We show that circulating levels of CS in human plasma are about 20 microg/ml. Most significantly, the endogenous concentration and CS disaccharide composition were not detectably altered by ingestion of CS, when the CS was taken alone or in combination with GlcN. On the other hand, the Cmax (single-dose study) and AUC values (multiple-dose study) for ingested GlcN were significantly reduced by combination dosing with CS, relative to GlcN dosing alone. CONCLUSIONS: We conclude that pain relief perceived following ingestion of CS probably does not depend on simultaneous or prior intake of GlcN. Further, such effects on joint pain, if present, probably do not result from ingested CS reaching the joint space but may result from changes in cellular activities in the gut lining or in the liver, where concentrations of ingested CS, or its breakdown products, could be substantially elevated following oral ingestion. Moreover, since combined dosing of GlcN with CS was found to reduce the plasma levels seen with GlcN dosing alone, any improved pain relief by combination dosing cannot be explained by higher circulating concentrations of GlcN.

Potential effects of chondroitin sulfate on joint swelling: a GAIT report.

The Glucosamine/chondroitin Arthritis Intervention Trial (GAIT) was a randomized double-blind placebo and active comparator (celecoxib) controlled trial of 1583 persons with symptomatic osteoarthritis (OA) of the knee(1). Patients randomized to celecoxib had significant improvement in knee pain compared to those randomized to placebo. No statistically significant improvement in knee pain compared to placebo was seen among patients randomized to the dietary supplements, although a subset of patients with moderate-to-severe knee pain at entry who were assigned to the combination of glucosamine and chondroitin sulfate did seem to experience some improvement. Additionally, patients taking chondroitin sulfate were noted to have a statistically significant improvement in knee joint swelling. An exploratory post hoc analysis of GAIT patients suggested the effect of chondroitin sulfate on joint swelling occurred more often in patients with milder pain and lower Kellgren-Lawrence Grade at entry.

Efficacy and safety of up to 192 weeks of etanercept therapy in patients with ankylosing spondylitis.

OBJECTIVE: Evaluate long-term safety and efficacy of etanercept treatment in patients with ankylosing spondylitis (AS). METHODS: Patients with AS who previously participated in a randomised controlled trial (RCT) of etanercept were eligible to enroll in a 168-week open-label extension (OLE). Safety end points included rates of adverse events (AE), serious adverse events (SAE), infections, serious infections and death. Efficacy end points included Assessment in Ankylosing Spondylitis (ASAS20) response, ASAS 5/6 response and partial remission rates. RESULTS: A total of 257 of 277 patients (92%) enrolled in the OLE. After up to 192 weeks of treatment with etanercept, the most common AEs were injection site reactions, headaches and diarrhoea. The exposure-adjusted rate of SAEs was 0.08 per patient-year. The rate of infections was 1.1 per patient-year, and the rate for serious infections was 0.02 per patient-year. No deaths were reported. Of patients who received etanercept in both the RCT and OLE and were still in the trial, 71% were ASAS20 responders at week 96, and 81% were responders at week 192. ASAS 5/6 response rates were 61% at week 96 and 60% at week 144, and partial remission response rates were 41% at week 96 and 44% at week 192. Placebo patients who switched to etanercept in the OLE showed similar patterns of efficacy maintenance. CONCLUSIONS: Etanercept was well tolerated for up to 192 weeks in patients with AS, with no unexpected AEs or SAEs observed. No deaths were reported. Improvements in the signs and symptoms of AS were maintained for up to 192 weeks.

Psoriatic arthritis: epidemiology, clinical features, course, and outcome.

Psoriatic arthritis (PsA) has been defined as a unique inflammatory arthritis associated with psoriasis. Its exact prevalence is unknown, but estimates vary from 0.3% to 1% of the population. The clinical features described initially are recognised by most experienced clinicians, although they are most distinct in early disease. Initially, PsA typically presents as an oligoarticular and mild disease. However, with time PsA becomes polyarticular, and it is a severe disease in at least 20% of patients. Patients with PsA who present with polyarticular disease are at risk for disease progression. In addition to progression of clinical and radiological damage, health related quality of life is reduced among patients with PsA. It important to note that patients included in recent drug trials resemble patients followed prospectively in a clinic.

Psoriatic arthritis therapy: NSAIDs and traditional DMARDs.

Non-steroidal anti-inflammatory drugs (NSAIDs) and traditional disease modifying antirheumatic drugs (DMARDs) are widely used in the treatment of psoriatic arthritis (PsA), but this is based more upon clinical experience than adequate evidence from clinical trials. This report summarises the results from available trials highlighting evidence of efficacy and deficiencies with respect to effect on joints and to a lesser degree cutaneous disease. The available published data on efficacy of NSAIDs, glucocorticoids, antimalarials, sulfasalazine, gold, methotrexate, azathioprine, and ciclosporin are detailed, as well as new data on leflunomide and other novel agents. The conclusions of this review are that evidence supports marginal efficacy of sulfasalazine and perhaps gold in the treatment of peripheral psoriatic arthropathy, and methotrexate and ciclosporin are effective for treating the skin disease although evidence for improvement of the arthropathy is empirical at best. New trials with standardised and validated outcome measures are required to better assess efficacy. Evaluating newer agents, against and in combination with traditional DMARDS, may further clarify the latter's role in the future management of this condition.

Treatment of ankylosing spondylitis with disease modifying antirheumatic drugs.

Ankylosing spondylitis (AS) is a common (prevalence 0.2-0.9%) chronic inflammatory disease that mainly affects young males and is characterised by inflammatory back pain with sacroiliitis and often arthritis of the peripheral joints. The disease can lead to deformities of the vertebral column, joints and extra-spinal structures, e.g. the eye (uveitis). Non-steroidal anti-inflammatory drugs (NSAIDs) and physical therapy seem to improve the long-term outcome of AS. However, the effect of disease modifying antirheumatic drugs (DMARDs) is less impressive compared with other rheumatic diseases, such as rheumatoid arthritis (RA). In placebo controlled trials, sulfasalazine showed some improvement of disease activity, especially in spondyloarthropathy patients with peripheral arthritis. Altogether the number of therapeutic options for AS is limited and other drugs, such as leflunomide or thalidomide, should be explored further in placebo-controlled trials.

A genomewide screen in multiplex rheumatoid arthritis families suggests genetic overlap with other autoimmune diseases.

Rheumatoid arthritis (RA) is an autoimmune/inflammatory disorder with a complex genetic component. We report the first major genomewide screen of multiplex families with RA gathered in the United States. The North American Rheumatoid Arthritis Consortium, using well-defined clinical criteria, has collected 257 families containing 301 affected sibling pairs with RA. A genome screen for allele sharing was performed, using 379 microsatellite markers. A nonparametric analysis using SIBPAL confirmed linkage of the HLA locus to RA (P < .00005), with lambdaHLA = 1.79. However, the analysis also revealed a number of non-HLA loci on chromosomes 1 (D1S235), 4 (D4S1647), 12 (D12S373), 16 (D16S403), and 17 (D17S1301), with evidence for linkage at a significance level of P<.005. Analysis of X-linked markers using the MLOD method from ASPEX also suggests linkage to the telomeric marker DXS6807. Stratifying the families into white or seropositive subgroups revealed some additional markers that showed improvement in significance over the full data set. Several of the regions that showed evidence for nominal significance (P < .05) in our data set had previously been implicated in RA (D16S516 and D17S1301) or in other diseases of an autoimmune nature, including systemic lupus erythematosus (D1S235), inflammatory bowel disease (D4S1647, D5S1462, and D16S516), multiple sclerosis (D12S1052), and ankylosing spondylitis (D16S516). Therefore, genes in the HLA complex play a major role in RA susceptibility, but several other regions also contribute significantly to overall genetic risk.

Laminin-5 promotes neurite outgrowth from central and peripheral chick embryonic neurons.

Laminin-5 (Ln-5) is an essential component of epithelial basal laminae that is also expressed in the developing nervous system. Here we use a convenient, simple and reproducible in vitro fluorescent assay to assess the neurite outgrowth promoting activity of purified Ln-5. Embryonic chick neurons from dorsal root ganglia, ciliary ganglia, and (to a lesser extent) retina extended neurites on Ln-5, but the neurite outgrowth promoting activity was not as great as that of Ln-1 or Ln-2. Neurons from diencephalon, telencephalon, and spinal cord did not respond to Ln-5.

Adhesive events in retinal development and function: the role of integrin receptors.

Cells in the developing retina contact a vast array of molecular cues in their microenvironment that are thought to guide their development. Many of these cues are embedded in the surface of neighboring cells or deposited within the extracellular matrix (ECM). Evidence has accumulated that cell-cell and cell-ECM interactions are essential in many phases of neural development, including neuroblast migration, determination of cell fate, axon outgrowth and synapse formation. In this chapter, we examine the developmental and functional roles fulfilled by integrins, a family of receptors for ECM molecules and cell adhesion molecules (CAMs). We have approached this problem by addressing a series of three questions: (1) which integrins are expressed in developing retina? (2) when and where are they expressed? and, (3) what functions do they carry out? Integrins have previously been implicated in axon extension, but new evidence suggests that they are also involved in earlier developmental events in preaxonal neuroblasts. High levels of expression of at least eight integrin subunits have been documented in these young retinal cells, and integrins containing the beta 1 subunit have been implicated in migration of adolescent retinal ganglion cells. Integrin expression persists through adulthood, both in the retina and in the neighboring layer of the retinal pigment epithelium (RPE). The integrin alpha v beta 5 has been shown to reside on the apical surface of the RPE and has been implicated in the phagocytosis of shed photoreceptor outer segments.

Imaging and mapping heparin-binding sites on single fibronectin molecules with atomic force microscopy.

Fibronectin is composed of multiple homologous repeats and contains many functional domains. Two major heparin-binding domains have previously been identified: the Hep I site near the amino terminus and the Hep II site near the carboxyl terminus. The Hep II site has been considered the high-affinity heparin-binding site based on studies of fibronectin fragments. However, few studies have been carried out on heparin binding by intact fibronectin. We imaged single fibronectin molecules as well as heparin-coated gold particles bound to whole dimeric plasma fibronectin molecules with tapping mode atomic force microscopy. We observed heparin-gold particles preferentially bound at two locations that correspond to the Hep I and Hep II sites. Quantitative analysis of images of individual fibronectin-heparin-gold complexes showed that almost twice as many heparin-gold particles bound to the N-terminal Hep I site compared to the Hep II site. In contrast to previous findings with fibronectin fragments, these results suggest that the Hep I site has a binding affinity higher than or comparable to the Hep II site in the intact fibronectin molecule.

Comparison of sulfasalazine and placebo for the treatment of axial and peripheral articular manifestations of the seronegative spondylarthropathies: a Department of Veterans Affairs cooperative study.

OBJECTIVE: To determine if the peripheral articular manifestations of the seronegative spondylarthropathies (SNSA) respond differently than the axial manifestations to treatment with sulfasalazine (SSZ). METHODS: This is a reanalysis of a previously reported series of randomized, double-blind, placebo-controlled, multicenter trials comparing the effects of SSZ, 2,000 mg/day, and placebo on the axial and peripheral articular manifestations of ankylosing spondylitis (AS), psoriatic arthritis (PsA), and reactive arthritis (ReA; Reiter's syndrome). Patients were classified as treatment responders on the basis of meeting predefined improvement criteria in 4 outcome measures: namely, patient and physician global assessments in all patients, morning stiffness and back pain in patients with axial manifestations, and joint pain/tenderness scores and joint swelling scores in patients with peripheral articular manifestations. RESULTS: Six hundred nineteen SNSA patients (264 AS, 221 PsA, and 134 ReA) were studied. One hundred eighty-seven of these patients had only axial manifestations of their disease, while 432 patients had peripheral articular manifestations. Of the patients with axial disease, 40.2% of the SSZ group and 43.3% of the placebo group met the predefined response criteria (P = 0.67). Of the peripheral articular group, 59.0% of the SSZ-treated patients and 42.7% of the placebo-treated patients showed a response (P = 0.0007). CONCLUSION: In a large group of affected individuals, the response of SNSA patients to SSZ appears to be related to the articular manifestations of their disease. These data demonstrate that the axial and peripheral articular manifestations of SNSA respond differently to treatment with SSZ. In SNSA patients with persistently active peripheral arthritis, SSZ is safe, well tolerated, and effective.

Global statistical tests for comparing multiple outcomes in rheumatoid arthritis trials. MIRA Trial Group.

OBJECTIVE: To evaluate global statistical tests (GSTs) of treatment effectiveness for rheumatoid arthritis (RA) trials measuring multiple outcomes. METHODS: Using outcome measures from American College of Rheumatology (ACR) core set variables available in 3 RA trials, GSTs were calculated using the O'Brien ranking procedure and a procedure for binary data. GSTs take correlations among outcomes into account. Power calculations using 1 trial data set provide comparisons of GSTs and ACR criteria for improvement. RESULTS: Spearman correlations among outcomes ranged from 0.21 to 0.73. Erythrocyte sedimentation rate had the lowest correlation with other outcomes in all 3 trials. Within a trial, joint swelling and joint tenderness or patient and physician assessment had the highest correlations, depending on the trial. Results were consistent with results using the ACR criteria, although the GST was more powerful. CONCLUSION: GSTs are a useful tool for comparing treatment effects across multiple clinically meaningful outcome measures. The GST allows easy inclusion of validated, reliable new measures that are not a part of ACR criteria, such as quality of life, and can be computed with or without selecting a cutoff point defining patient improvement. GSTs should be considered for rheumatic disease treatment trials.

Imaging real-time proteolysis of single collagen I molecules with an atomic force microscope.

The dynamic process of synthesis and degradation of extracellular matrix molecules, including various collagens, is important in normal physiological functions and pathological conditions. Existing models of collagen enzymatic degradation reactions are derived from bulk biochemical assays. In this study, we have imaged in real-time individual collagen I molecules and their proteolysis by Clostridium histolyticum collagenases in phosphate-buffered saline (PBS) with atomic force microscopy (AFM). We have also imaged the likely binding and unbinding of collagenase molecules to single triple-helical collagen I molecules and subsequent proteolysis of subsets of the collagen molecules. The proteolysis of collagen molecules was inhibited by reduced calcium and acidification. Results from AFM study of collagen proteolysis are consistent with SDS-PAGE biochemical assays. The real-time proteolysis of single collagen I molecules followed simple Michaelis-Menton kinetics previously derived from bulk biochemical assays. This is the first report of imaging real-time proteolysis of single macromolecules and its inhibition on a molecular scale. A strong correspondence between the kinetics of proteolysis of single collagen molecules and the kinetics of proteolysis derived from bulk biochemical assays will have a wide applicability in examining real-time enzymatic reactions and their regulation at single molecule structural level. Such real-time study of single molecule proteolysis could provide a better understanding of the interactions between proteases and target proteins as well as proteases and protease inhibitors.

Baseline relationships between psoriasis and psoriatic arthritis: analysis of 221 patients with active psoriatic arthritis. Department of Veterans Affairs Cooperative Study Group on Seronegative Spondyloarthropathies.

OBJECTIVE: To determine differences in disease onset, extent, and manifestations of psoriasis among patients with active, inflammatory psoriatic arthritis (PsA), and to examine relationships that may exist between psoriasis and PsA. METHODS: Baseline demographic, clinical, and laboratory data were analyzed from 221 patients enrolled in a multicenter cooperative study, and relationships between measures of psoriasis and PsA were determined. RESULTS: Mean percentage of body surface area (BSA) affected by psoriasis was modest (12+/-17), and mean severity of erythema, induration, and scaling was moderate (4.9+/-2.1 on a 0-9 scale). Spanish Americans tended to have a higher mean percentage of BSA (18.5%) than Caucasians (11%; p = 0.067), as well as higher target lesion severity (5.55 vs. 4.84; p = 0.077). Patients with psoriatic nail disease (180/221, 81%) had significantly greater number of involved distal interphalangeal (DIP) joints (p = 0.004). There were no other significant associations of skin pattern or regional involvement with PsA. CONCLUSION: Patients with active PsA have generally mild skin disease, and baseline relationships between psoriasis and PsA tend to be weak except for nail involvement and DIP joint activity.

The prevalence of sacroilitis in psoriatic arthritis: new perspectives from a large, multicenter cohort. A Department of Veterans Affairs Cooperative Study.

OBJECTIVE: To determine the prevalence of radiographic evidence of sacroiliitis in a large population of patients with psoriatic arthritis. PATIENTS AND DESIGN: Patients were recruited from 15 clinical centers. This was part of a large, multicenter study of patients with an established diagnosis of ankylosing spondylitis, psoriatic arthritis, or reactive arthritis. For this cohort, an established diagnosis of psoriatic arthritis was required, with cutaneous manifestations and involvement of at least three appendicular joints. At entry, patients were not selected for the presence of axial involvement. Radiographs - one anteroposterior view of the pelvis and one oblique view of each sacroiliac joint - were graded using the New York classification scale by a musculoskeletal radiologist masked to the specific diagnosis and clinical symptoms. Re-evaluation of 10% of the films 3 years later quantified intraobserver variability. RESULTS: Two hundred and two patients with psoriatic arthritis were studied. Duration of the disease averaged 12 years; all patients had psoriasis and peripheral arthritis. The prevalence of radiographic evidence of sacroiliitis (grade 2 or higher) was 78%; 71% of these had grade 3 disease. CONCLUSIONS: Previously reported prevalence of sacroiliitis in patients with psoriatic arthritis ranges from 30% to 50%. The prevalence of radiographic evidence of sacroiliitis in this large multicenter cohort of patients with appendicular psoriatic arthritis was substantially higher.

Early undifferentiated connective tissue disease (CTD). VI. An inception cohort after 10 years: disease remissions and changes in diagnoses in well established and undifferentiated CTD.

OBJECTIVE: (1) To review the diagnoses after 10 years in patients who were identified within 12 months of the onset of well established and undifferentiated connective tissue diseases (CTD). (2) To examine the death rates and disease remissions in these patients. METHODS: This inception cohort of 410 patients had less than one year of signs and/or symptoms of CTD. Diagnoses of rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), and poly/dermatomyositis (PM/DM) were made in 197 patients using accepted diagnostic and classification criteria. Diagnoses of undifferentiated CTD were made in 213 patients. These latter patients were placed in 3 categories: isolated Raynaud's phenomenon (RP), unexplained polyarthritis (UPA), and undifferentiated CTD (UCTD), defined as meeting at least 3 of 11 specific manifestations of CTD. The diagnoses and remissions in all patients after 10 years were determined. RESULTS: Patients with well established CTD tended to remain with the original diagnosis. The 10 year survival was at least 87% in all diagnostic categories, with the exception of SSc, in which it was 56%. The progression of UPA to RA occurred infrequently. The presence of antinuclear antibodies suggested that UPA may develop additional symptoms and/or a specific diagnosis, and RP in these patients increased the likelihood of progressing to UCTD or a specific well established CTD. Ten percent of patients with RP progressed to SSc. In patients with UCTD, joint pain/tenderness and swelling counts were associated with progression to other diagnoses including RA, while either serositis, malar rash, or discoid lupus suggested the eventual diagnosis of SLE. CONCLUSION: The survival of patients with SSc was poor, with most dying early in the course of their disease. Remissions were seen in all groups of patients except SSc. The remissions were sometimes transient in SLE. Undifferentiated disease at initial examination within 12 months of onset usually remains undifferentiated.

Radiographic diagnosis of sacroiliitis--are sacroiliac views really better?

OBJECTIVE: To determine whether detailed oblique radiographs of the sacroiliac (SI) joints provide significant diagnostic advantage to a single AP projection of the pelvis in establishing the presence and severity of sacroiliitis. METHODS: Radiographs (both AP pelvis and detailed oblique projections) of 445 right SI joints and 442 left SI joints were obtained from patients with an established diagnosis of a seronegative spondyloarthropathy, and interpreted for severity. Data for the right and left SI joints were analyzed, comparing interpretations of severity based on AP pelvis projections with oblique views. RESULTS: Analysis of these data showed an agreement rate between AP views and SI views of 89.7% for the right SI joint radiographs and 86.4% for the left SI joint. There was no instance in which a patient with "unequivocal abnormalities"of the SI joints on the AP pelvis was read as having "normal" SI views. Similarly, there were no cases in which "normal" SI joints on AP pelvis films were read as having unequivocal abnormalities on SI views. CONCLUSION: In this group of patients with seronegative spondyloarthropathies, there was very close agreement between severity score of sacroiliitis from AP pelvis radiographs and SI joint views. We conclude that in most circumstances, the AP pelvis film will yield the diagnosis of sacroiliitis without the additional radiation exposure and expense related to specific SI joint radiographs.