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ID PMID Title PublicationDate abstract
16508941 CXCL16-mediated cell recruitment to rheumatoid arthritis synovial tissue and murine lymph 2006 Mar OBJECTIVE: Rheumatoid arthritis (RA) is characterized by profound mononuclear cell (MNC) recruitment into synovial tissue (ST), thought to be due in part to tumor necrosis factor alpha (TNFalpha), a therapeutic target for RA. Although chemokines may also be involved, the mechanisms remain unclear. We undertook this study to examine the participation of CXCL16, a novel chemokine, in recruitment of MNCs to RA ST in vivo and to determine the signal transduction pathways mediating this process. METHODS: Using a human RA ST-SCID mouse chimera, immunohistochemistry, enzyme-linked immunosorbent assay, real-time reverse transcription-polymerase chain reaction, flow cytometry, and in vitro chemotaxis assays, we defined the expression and function of CXCL16 and its receptor, CXCR6, as well as the signal transduction pathways utilized by them for MNC homing in vitro and in vivo. RESULTS: CXCL16 was markedly elevated in RA synovial fluid (SF) samples, being as high as 145 ng/ml. Intense macrophage and lining cell staining for CXCL16 in RA ST correlated with increased CXCL16 messenger RNA levels in RA ST compared with those in osteoarthritis and normal ST. By fluorescence-activated cell sorting analysis, one-half of RA SF monocytes and one-third of memory lymphocytes expressed CXCR6. In vivo recruitment of human MNCs to RA ST implanted in SCID mice occurred in response to intragraft injection of human CXCL16, a response similar to that induced by TNFalpha. Lipofection of MNCs with antisense oligodeoxynucleotides for ERK-1/2 resulted in a 50% decline in recruitment to engrafted RA ST and a 5-fold decline in recruitment to regional lymph nodes. Interestingly, RA ST fibroblasts did not produce CXCL16 in response to TNFalpha in vitro, suggesting that CXCL16 protein may function in large part independently of TNFalpha. CONCLUSION: Taken together, these results point to a unique role for CXCL16 as a premier MNC recruiter in RA and suggest additional therapeutic possibilities, targeting CXCL16, its receptor, or its signaling pathways.
18385277 Rates of new-onset psoriasis in patients with rheumatoid arthritis receiving anti-tumour n 2009 Feb BACKGROUND: Anti-tumour necrosis factor (TNF)alpha treatments improve outcome in severe rheumatoid arthritis (RA) and are efficacious in psoriasis and psoriatic arthritis. However recent case reports describe psoriasis occurring as an adverse event in patients with RA receiving anti-TNFalpha therapy. OBJECTIVES: We aimed to determine whether the incidence rate of psoriasis was higher in patients with RA treated with anti-TNFalpha therapy compared to those treated with traditional disease-modifying antirheumatic drugs (DMARDs). We also compared the incidence rates of psoriasis between the three anti-TNFalpha drugs licensed for RA. METHODS: We studied 9826 anti-TNF-treated and 2880 DMARD-treated patients with severe RA from The British Society for Rheumatology Biologics Register (BSRBR). All patients reported with new onset psoriasis as an adverse event were included in the analysis. Incidence rates of psoriasis were calculated as events/1000 person years and compared using incidence rate ratios (IRR). RESULTS: In all, 25 incident cases of psoriasis in patients receiving anti-TNFalpha therapy and none in the comparison cohort were reported between January 2001 and July 2007. The absence of any cases in the comparison cohort precluded a direct comparison; however the crude incidence rate of psoriasis in those treated with anti-TNFalpha therapy was elevated at 1.04 (95% CI 0.67 to 1.54) per 1000 person years compared to the rate of 0 (upper 97.5% CI 0.71) per 1000 person years in the patients treated with DMARDs. Patients treated with adalimumab had a significantly higher rate of incident psoriasis compared to patients treated with etanercept (IRR 4.6, 95% CI 1.7 to 12.1) and infliximab (IRR 3.5, 95% CI 1.3 to 9.3). CONCLUSIONS: Results from this study suggest that the incidence of psoriasis is increased in patients treated with anti-TNFalpha therapy. Our findings also suggest that the incidence may be higher in patients treated with adalimumab.
16766364 Interleukin-1beta influences the effect of infliximab on temporomandibular joint pain in r 2006 May OBJECTIVES: The aim of this study was to investigate the influence of plasma and synovial fluid tumour necrosis factor alpha (TNFalpha), interleukin-1beta (IL-1beta), IL-6, soluble TNF receptor II (TNF-sRII), IL-1 receptor antagonist (IL-1ra), soluble IL-1 receptor II (IL-1sRII) and IL-10 on the effect of the TNFalpha antibody infliximab on temporomandibular joint (TMJ) pain in patients with active rheumatoid arthritis (RA). METHODS: Fifteen patients with TMJ pain taking methotrexate were included in the study. The effect of intravenous infusions of infliximab was assessed after 14 or 22 weeks. TMJ resting and movement pain was assessed by a visual analogue scale (VAS) (0-100 mm) and samples of venous blood and TMJ synovial fluid were collected before and after treatment. RESULTS: The effect of infliximab on TMJ pain was influenced by pretreatment plasma levels of IL-1beta, IL-1ra, and IL-10 as well as pretreatment levels of TMJ synovial fluid IL-1sRII. High pretreatment levels of these cytokines and receptors as well as the presence of rheumatoid factor (RF) were associated with no or minor reduction in TMJ pain after treatment. CONCLUSIONS: Systemic treatment of RA with a combination of infliximab and methotrexate seems to be insufficient to alleviate TMJ pain in patients with RF or high pretreatment plasma levels of IL-1beta.
19048782 [Synthesis and antiinflammation activity of aromatic aminoketone compounds, a new type of 2008 Sep A series of aromatic aminoketones were synthesized by Mannich reaction. Structures of these compounds were confirmed by 1H NMR, MS and HRMS or element analysis. Pharmacological screening showed that most target compounds inhibited the release of beta-glucuronidase in polymorphonuclear leucocytes by PAF (platelet activating factor) and compounds MA12, MA13, MA18, MA21 and MA33 were more active. The study suggests that target compounds are potential PAF receptor antagonists and their anti-inflammatory activities are due to the inhibition of release of lysosomal enzyme.
18199596 Interleukin 27 attenuates collagen-induced arthritis. 2008 Oct OBJECTIVE: To investigate the potential role of interleukin (IL) 27 in rheumatoid arthritis (RA) by examining the expression of IL27 in the articular joints of patients with RA and the effect of recombinant IL27 in vivo in a murine model of collagen-induced arthritis (CIA). METHODS: Synovial membranes from patients with RA were examined for the presence of IL27 by immunohistochemistry and by western blot. Mice developing CIA were treated with IL27 and the ensuing disease progression and immunological profile determined. The effect of IL27 on T-cell response in vitro was also ascertained. RESULTS: IL27 was clearly detected in the RA synovial membranes. Short-term administration of IL27 at the onset of the disease significantly attenuated disease severity compared with untreated controls. Histological examination showed that while untreated mice developed severe cellular infiltration in the joints, synovial hyperplasia and joint erosion, this pathology was profoundly reduced in IL27-treated animals. Treatment of mice with IL27 also decreased the amounts of serum IL6 and collagen-specific IgG2a. Spleen and lymph node cells from the IL27-treated mice produced significantly less interferon gamma and IL17 than cells from the control mice when cultured with collagen in vitro. CONCLUSION: These results demonstrate that IL27 may be a potential therapeutic agent against RA at the onset of the disease.
16432689 [Instability of the upper cervical spine due to rheumatism]. 2006 Mar Rheumatic manifestation at the cervical spine occurs in more than 50% of all cases in the natural course of this disease. The first cervical manifestation takes place in the upper cervical spine. The initial involvement of the C1/C2 segment leads to atlantodental subluxation. Progressive destruction can result in vertical instability, which is characterized by cranial subluxation of the odontoid process with the danger of resulting stenosis and cervical myelopathy. The goal of diagnosis has to be the early recognition of these changes to establish an effective treatment protocol. Persistent pain, neurological deficits, and progressive radiological signs for instability are indications for operative stabilizing procedures. These procedures avoid progressive destruction and improve the prognosis regarding pain decrease, regression of neurological deficits, and life expectancy.
18534398 Scintigraphic assessment of patellar viability in total knee arthroplasty after lateral re 2009 Jun To what extent lateral retinacular release done in total knee arthroplasty compromises patellar viability has been debated. This study is a prospective study to assess patellar viability using Technetium-99m methylene diphosphate (Tc-99m MDP) scintigraphy. Between 2005 and 2006, 59 patients (72 knees) who underwent primary total knee arthroplasty were studied, of which 36 required lateral release. All patients underwent regional bone scan using Tc-99m MDP before and 1 to 3 weeks after the surgery. Two nuclear medicine consultants using both qualitative and quantitative assessment interpreted the scans independently. Fourteen knees with lateral release showed scintigraphic signs of hypovascularity in the early postoperative period that normalized in 8-week postoperative period. This study documents the greater incidence of transient patellar hypovascularity associated with lateral release.
17645236 A presenilin 1 mutation (L420R) in a family with early onset Alzheimer disease, seizures a 2007 Jun Over 100 mutations in the presenilin-1 gene (PSEN1) have been shown to result in familial early onset Alzheimer disease (EOAD), but only a relatively few give rise to plaques with an appearance like cotton wool (CWP) and/or spastic paraparesis (SP). A family with EOAD, seizures and CWP was investigated by neuropathological study and DNA sequencing of the PSEN1 gene. Abeta was identified in leptomeningeal vessels and in cerebral plaques. A single point mutation, p.L420R (g.1508T > G) that gives rise to a missense mutation in the eighth transmembrane (TM8) domain of PS1 was identified in two affected members of the family. p.L420R (g.1508T > G) is the mutation responsible for EOAD, seizures and CWP without SP in this family.
16794815 Determination of ceruloplasmin in human serum by SEC-ICPMS. 2006 Sep This paper describes an analytical method for the determination of ceruloplasmin (Cp) in human serum. The method uses immunoaffinity chromatography and size-exclusion chromatography (SEC) to "purify" the serum sample prior to analysis of 63Cu and 65Cu by inductively-coupled plasma mass spectrometry (ICPMS). By removing the six most abundant proteins from serum with immunoaffinity chromatography and by using SEC to separate Cu bound by Cp from any free Cu that might be present in the serum sample, we demonstrated that SEC-ICPMS can accurately and reproducibly measure Cp in the ERM DA470 reference serum. Cp identification is based on retention time match of the unknown in the serum sample with the Cp external standard and the presence of 63Cu and 65Cu at a ratio of 2.2+/-0.1. This method was used to analyze a reference serum certified for Cp, 47 serum samples from four different diseases and a set of normal controls. The reference serum and a serum sample from a patient with myocardial infarction, as well as a Cp standard, were also analyzed by electrospray mass spectrometry to confirm the presence of Cp in the SEC fraction known to contain 63Cu.
17543160 Unusual association between pure red cell aplasia and primary Sjögren's syndrome: a case 2007 Mar Pure red cell aplasia (PRCA) is an acute anemia due to selective suppression of erythropoiesis. We report a case of PRCA diagnosed before the onset of primary Sjögren's syndrome (SS). A young woman, with autoimmune thyroiditis, developed polyarthritis with ANA and Rheumatoid factor positivity, diagnosed as Rheumatoid arthritis. During the time she developed anti-Ro and anti-La antibodies and deformities at proximal interphalangeal joints. After 4 years, she developed severe acute anemia, without reticolocytes: a bone marrow biopsy indicated a PRCA and she started transfusions, steroids, cyclosporin. A steroid-dependent anemia persisted. After 2 years she developed sicca, parotid swelling, fatigue, mild leukopenia, elevated serum creatinine, hypokalemia, hyposthenuria and tubular proteinuria. Lip biopsy and dacriologic tests confirmed a diagnosis of SS, while X-ray revealed a deforming non-erosive arthropathy (Jaccoud type). In present case, PRCA could be considered an autoimmune bone marrow disease within SS, whose extra-glandular manifestations onset before the sicca symptoms.
17922687 Amyloid deposition in primary pulmonary marginal zone B-cell lymphoma of mucosa-associated 2007 Nov A rare association between primary pulmonary marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), and pulmonary immunoglobulin light chain (AL) amyloidosis is described in a 65-year-old woman suffering from rheumatoid arthritis (RA). All four nodules in the resected upper lobe of the lung had a similar histological appearance. They were composed of small-medium-sized atypical lymphocytes. Centrocyte-like cells had lymphoepithelial lesions. Immunohistochemically, the tumor cells clonally expressed B-cell markers, and demonstrated clonal rearrangement of the immunoglobulin heavy chain gene on polymerase chain reaction. Based on these findings the diagnosis of primary pulmonary MALT lymphoma was made. In addition, uniform eosinophilic material deposition was identified randomly within the tumor. It was Congophilic and exhibited apple-green birefringence on polarizing microscopy, and remained unaffected by potassium permanganate digestion. Deposited material was immunoreactive to lambda light chain. It was concluded that this material was AL amyloid in primary pulmonary MALT lymphoma. Plasma cells with mRNA of lambda chain was found infiltrated along the border of amyloid deposition. Finally, it is speculated that primary pulmonary MALT lymphoma developing in an autoimmune setting, RA in the present case, is associated with overproduction and abnormal clearance of immunoglobulin by the tumor cells, resulting in AL amyloidosis within the tumor.
17916444 TNFalpha blockade in human diseases: mechanisms and future directions. 2008 Feb Tumor necrosis factor-alpha (TNFalpha) antagonists have shown remarkable efficacy in a variety of immune-mediated inflammatory diseases (IMIDs). Therapeutic scope and limitations of these agents are reviewed in a recently published article in the Journal. In spite of their therapeutic popularity, little is known about their modes of action in vivo and factors that limit their scope of therapeutic use. Intriguingly, while all TNFalpha antagonists including blocking antibodies and soluble receptors are effective in certain IMIDs, only anti-TNFalpha antibodies are effective in other IMIDs. Early efforts at understanding how TNFalpha antagonists act in IMIDs centered on their ability to neutralize soluble TNFalpha or to block TNF receptors from binding to their ligands. Subsequent studies suggested a role of complement-mediated lysis or antibody-dependent cell cytotoxicity in their therapeutic effects. More recent models postulate that TNFalpha blockers may act by affecting intracellular signaling, with the end result being a hastened cell cycle arrest, apoptosis, suppression of cytokine production, or improved Treg cell function. TNFalpha antagonists can also modulate the functions of myofibroblasts and osteoclasts, which might explain how TNFalpha antagonists reduce tissue damage in chronic IMIDs. Focusing on the human therapeutic experience, this analytical review will review the biology of mechanisms of action, the limiting factors contributing to disease restriction in therapeutic efficacy, and the mechanism and frequency of treatment-limiting adverse responses of TNFalpha antagonists. It is hoped that the overview will address the needs of clinicians to decide on optimal use, spur clinical innovation, and incite translational researchers to set priorities for in vivo human investigations.
18512780 Different T cell subsets in the nodule and synovial membrane: absence of interleukin-17A i 2008 Jun OBJECTIVE: To determine gene expression of the interleukin-17 (IL-17) family members (IL-17A-F) in rheumatoid subcutaneous nodules, and to assess the cytokines involved in regulating IL-17A expression. METHODS: Total RNA was isolated from 19 nodules obtained from 16 different patients with rheumatoid arthritis (RA). Reverse transcription-polymerase chain reaction (PCR) was used to screen for gene expression of the IL-17 subtypes (IL-17A-F) in all nodules. Quantitative real-time PCR was used to measure the expression of interferon-gamma (IFN gamma), IL-6, IL-23, IL-12, and transforming growth factor beta (TGFbeta), relative to GAPDH as control, in a subset of 10 nodules. RESULTS: IL-17A gene expression was present in only 1 of 19 nodules, IL-17B in 17 of 19 nodules, IL-17C in 18 of 19 nodules, IL-17D in 16 of 19 nodules, and IL-17E in 3 of 19 nodules. IL-17F was absent in all samples. Cytokines that stimulate IL-17A production (IL-6, IL-23) as well as those that inhibit IL-17A production (IL-12, IFN gamma, TGFbeta) were present in the majority of nodules. Quantitative real-time PCR showed a similar pattern of gene expression for the individual cytokines between the different nodules. The mean +/- SD expression of IL-6 relative to GAPDH was 2.28 +/- 2.2 ng, and that of TGFbeta was 2.96 +/- 1.14 ng. There was a lower relative expression of IL-23 (0.05 +/- 0.05 ng), while the expression of IFN gamma was 0.67 +/- 0.68 ng and that of IL-12 was 0.48 +/- 0.23 ng. CONCLUSION: IL-17 family members are varyingly expressed in rheumatoid nodules. The paucity of IL-17A in nodules suggests an important difference from that observed in the synovium. The expression of IL-23 below a critical threshold level seems the most likely explanation for the virtual absence of IL-17A. The presence of tissue destruction within the nodule despite the absence of IL-17A suggests that IL-17A may be an important amplifier rather than an absolute requirement for inflammation in RA.
18671292 Lewis-Sumner syndrome associated with infliximab therapy in rheumatoid arthritis. 2008 Oct We report 2 cases of Lewis-Sumner syndrome (LSS) diagnosed in patients suffering from rheumatoid arthritis undergoing treatment with the antitumor necrosis factor alpha (TNF-alpha) monoclonal antibody infliximab. While experiencing clinical improvement in their arthritic symptoms, both patients experienced sensory deficits and weakness in multiple nerve distributions. They had electrodiagnostic evidence of motor conduction block and subsequent improvement with intravenous immunoglobulin (IVIg). We describe the details of the cases and review the literature on immune-mediated neuropathies associated with anti-TNF-alpha therapy.
17195044 Rosmarinic acid induces apoptosis of activated T cells from rheumatoid arthritis patients 2007 Jan T cells play an important role in the initiation and the progression of rheumatoid arthritis (RA) and depletion of potentially pathogenic T cells was suggested as an important therapeutic protocol. We determined if rosmarinic acid (RosA), known as a secondary metabolite from herbal plants, had apoptotic activity toward T cells from RA patients and further verified target T-cell subsets. CD3(+)CD25(+) activated T-cell subsets from most of the RA patients displayed significantly higher apoptosis rates than did the PBMCs and total CD3(+) T cells. Furthermore, activated and effector CD4(+) T cells, including CD4(+)CD25(+) and CD4(+)CD45RO(+) T cells, had a tendency of being more susceptible to RosA-induced apoptosis than that of resting and naïve T-cell subsets. RosA induced the release of cytochrome c from mitochondria and the blockage of mitochondrial depolarization inhibited apoptosis. Taken together, these results suggest that RosA induces apoptosis of activated T-cell subsets from RA patients via a mitochondrial pathway.
16703558 Endogenous endophthalmitis by Propionibacterium acnes associated with leflunomide and adal 2006 Mar PURPOSE: To report a case of unusual endogenous endophthalmitis associated with the use of leflunomide and adalimumab. METHODS: A 48-year-old woman on treatment with leflunomide and adalimumab for rheumatoid arthritis developed an endogenous endophthalmitis caused by Propionibacterium acnes. Diagnosis was confirmed by polymerase chain reaction and positive cultures. The patient underwent surgical treatment and intravitreal vancomycin, but the eye developed retinal fibrosis and untreatable retinal detachment. RESULTS: This report of endogenous endophthalmitis associated with the use of anti-tumor necrosis factor alpha (anti -TNF-a) drugs is consistent with those in the literature. P. acnes may induce pathologic reactions in compromised patients and cause endophthalmitis, but only after ocular surgery or in intravenous drug users. The Naranjo probability scale indicated a probable relationship between the drugs and the infection. CONCLUSIONS: Awareness of atypical infectious conditions in patients on anti-TNF-a drugs is critical for early diagnosis and good outcome.
17511792 Adult-onset Still's disease. 2009 Jul BACKGROUND: Adult-onset Still's disease (AOSD) is a febrile disorder of unknown aetiology characterised by typical spiking fever, evanescent rash, arthralgia and leucocytosis. METHODS: According to the diagnostic criteria of AOSD, we identified 84 patients between 1990 and 2003. The aim of this study was to analyse the characteristics of AOSD in Turkish patients who were followed-up in a tertiary referral centre. RESULTS: Of 84 patients of AOSD, 59 (70.2%) were female, 25 (29.8%) were male. Arthralgia (96.4%), fever (95.2%), arthritis (69%), sore throat (65.5%) and typical rheumatoid rash (59.5%) were the most common findings. The mean value of laboratory findings were as follows; C-reactive protein level of 11.59 +/- 6.81 mg/dl, erythrocyte sedimentation rate (ESR) of 89.05 +/- 31 mm/h, leukocyte count of 16,234.51 +/- 7785.2/microl. Leucocytosis was present in 69 patients (84.15%). Forty-eight patients had a WBC count >or= 15,000/microl. Hypoalbuminaemia was present in 35 patients. Abnormal levels of aspartate aminotransferase and alanine aminotransferase were observed in 30 patients, whereas abnormal levels of alkaline phosphatase in 16 patients. Thirty-seven patients had an ESR value of more than 100 mm/h. Thirty-two patients had a ferritin value of more than 1000 ng/dl. CONCLUSION: High fever, sore throat, rheumatoid rash, polyarthritis, hyperferritinaemia (>or= 1000 ng/ml), leucocytosis with a neutrophilic predominance, anaemia and hypoalbuminaemia were remarkable observations in the initial examination.
16467033 Progress and regression within primary Sjögren's syndrome. 2006 Jan The purpose of this review is to give a modern view and an update of important areas in primary Sjögren's syndrome (SS), which may be the most common of the autoimmune systemic rheumatic diseases. Interest in aspects of primary SS including clinical manifestations, pathogenesis, aetiology, treatment, prognosis, etc has increased during the past three decades, the volume of scientific papers and the number of theses being the indicators. However, only a fraction of the money that is used for research into rheumatoid arthritis (RA) is used for SS, and the statement that SS is under-diagnosed, under-treated and under-researched will still be valid for several years to come. The topics that are focused on in this review are: (a) clinical areas with subsections on signs and symptoms, terminology, predictors for development of non-Hodgkin malignant lymphoma (NHML) and prognosis, (b) treatment, (c) the Danger model (aetiopathogenesis) and (d) pathology, including immunoglobulin G4 (IgG4)-positive cells.
17633444 [CD147 stimulates the angiogenesis in rheumatoid synovium via the activation of vascular e 2007 May AIM: To observe the correlation between vascular endothelial growth factor (VEGF) and CD147 expressed in the rheumatoid synovium and to investigate the effect of CD147 of cultured rheumatoid fibroblast-like synoviocytes (FLS) on the production of VEGF. METHODS: The presence of CD147 and VEGF in the rheumatoid synovium derived from 15 patients with RA and 4 patients with osteoarthritis (OA) was detected by streptavidin/peroxidase (SP) immunostaining. FLS were cultured by enzymatic digestion of synovial tissues and incubated in 24-well plates. Then different concentration of LY294002, PD98059, SP600125, SB203580 and HAb18G mAb was added to each well. VEGF in the culture supernatant was measured by sandwich ELISA. RESULTS: CD147 and VEGF in synovium from 15 patients with RA showed high expression, while CD147 and VEGF in synovium from 4 patients with OA showed low expression. Macrophages, fibroblast-like synovial cells and lymphocytes were demonstrated to express CD147 while synovial lining cells, fibroblasts surrounding microvessels and vascular smooth muscle cells were demonstrated to express VEGF. Statistic analysis indicates that VEGF production was correlated with the levels of CD147 expression. VEGFproduction was suppressed when CD147 expression was inhibited by LY294002 or HAb18G mAb. CONCLUSION: CD147 can regulate the angiogenesis in rheumatoid arthritis by VEGF. The low levels of CD147 expressed by FLS cells decrease the production of VEGF via the PI3K-Akt signaling pathway. These findings further highlight the importance of CD147 in pannus formation and angiogenesis.
17292766 Assessment of upper gastrointestinal safety of etoricoxib and diclofenac in patients with 2007 Feb 10 BACKGROUND: Upper gastrointestinal safety of cyclo-oxygenase (COX)-2 selective inhibitors versus traditional non-steroidal anti-inflammatory drugs (NSAIDs) has not been assessed in trials that simulate standard clinical practice. Our aim was to assess the effects of these drugs on gastrointestinal outcomes in a population that includes patients taking gastrointestinal protective therapy. METHODS: A prespecified pooled intent-to-treat analysis of three double-blind randomised comparisons of etoricoxib (60 or 90 mg daily) and diclofenac (150 mg daily) in 34 701 patients with osteoarthritis or rheumatoid arthritis was done for upper gastrointestinal clinical events (bleeding, perforation, obstruction, or ulcer) and the subset of complicated events (perforation, obstruction, witnessed ulcer bleeding, or significant bleeding). We also assessed such outcomes in patients who were taking concomitant proton pump inhibitors (PPIs) or low-dose aspirin. These trials are registered with , with the numbers , , and . FINDINGS: Overall upper gastrointestinal clinical events were significantly less common with etoricoxib than with diclofenac (hazard ratio [HR] 0.69, 95% CI 0.57-0.83; p=0.0001). There were significantly fewer uncomplicated gastrointestinal events with etoricoxib than there were with diclofenac (0.57, 0.45-0.74; p<0.0001); there was no difference in complicated events (0.91, 0.67-1.24; p=0.561). PPIs were used concomitantly for at least 75% of the study period by 13 862 (40%) and low-dose aspirin by 11 418 (33%) patients; treatment effects did not differ significantly in these individuals. INTERPRETATION: There were significantly fewer upper gastrointestinal clinical events with the COX-2 selective inhibitor etoricoxib than with the traditional NSAID diclofenac due to a decrease in uncomplicated events, but not in the more serious complicated events. The reduction in uncomplicated events with etoricoxib is maintained in patients treated with PPIs and is also observed with regular low-dose aspirin use.