Approaches to rheumatoid arthritis in 2000

Improvement in 5-year mortality in incident rheumatoid arthritis compared with the general population-closing the mortality gap

OBJECTIVE

Excess mortality in rheumatoid arthritis (RA) is expected to have improved over time, due to improved treatment. Our objective was to evaluate secular 5-year mortality trends in RA relative to general population controls in incident RA cohorts diagnosed in 1996-2000 vs 2001-2006.

METHODS

We conducted a population-based cohort study, using administrative health data, of all incident RA cases in British Columbia who first met RA criteria between January 1996 and December 2006, with general population controls matched 1:1 on gender, birth and index years. Cohorts were divided into earlier (RA onset 1996-2000) and later (2001-2006) cohorts. Physician visits and vital statistics data were obtained until December 2010. Follow-up was censored at 5 years to ensure equal follow-up in both cohorts. Mortality rates, mortality rate ratios and HRs for mortality (RA vs controls) using proportional hazard models adjusting for age, were calculated. Differences in mortality in RA versus controls between earlier and later incident cohorts were tested via interaction between RA status (case/control) and cohort (earlier/later).

RESULTS

24 914 RA cases and controls experienced 2747 and 2332 deaths, respectively. Mortality risk in RA versus controls differed across incident cohorts for all-cause, cardiovascular diseases (CVD) and cancer mortality (interactions p<0.01). A significant increase in mortality in RA versus controls was observed in earlier, but not later, cohorts (all-cause mortality adjusted HR (95% CI): 1.40 (1.30 to 1.51) and 0.97 (0.89 to 1.05), respectively).

CONCLUSIONS

In our population-based incident RA cohort, mortality compared with the general population improved over time. Increased mortality in the first 5 years was observed in people with RA onset before, but not after, 2000.

Local gene transfer of OPG prevents joint damage and disease progression in collagen-induced arthritis

This study examined the influence of osteoprotegerin (OPG) gene transfer on a murine collagen-induced arthritis model. A single periarticular injection of AAV-OPG or AAV-LacZ on the arthritic paw successfully incorporated the exogenous gene to the local tissue and resulted in marked transgene expression in the joint homogenate for at least three weeks. Clinical disease scores were significantly improved in OPG treated mice starting at 28-day post-treatment (P < 0.05). Histological assessment demonstrated that OPG gene transfer dramatically protected mice from erosive joint changes compared with LacZ controls (P < 0.05), although treatment appeared less effective on the local inflammatory progress. MicroCT data suggested significant protection against subchondral bone mineral density changes in OPG treated CIA mice. Interestingly, mRNA expressions of IFN-g and MMP3 were noticeably diminished following OPG gene transfer. Overall, gene transfer of OPG effectively inhibited the arthritis-associated periarticular bone erosion and preserved the architecture of arthritic joints, and the study provides evidence that the cartilage protection of the OPG gene therapy may be associated with the down-regulation of MMP3 expression.

Lack of association between CAG repeat polymorphism in the androgen receptor gene and the outcome of rheumatoid arthritis treatment with leflunomide

Purpose

Leflunomide (LEF) is a disease-modifying antirheumatic drug used for treating rheumatoid arthritis (RA) and the action of which may be modified by sex hormones. The aim of this study was to examine the association between CAG repeat polymorphism in the androgen receptor (AR) gene and the response to treatment with LEF in women with RA.

Methods

We studied 114 women diagnosed with RA and treated with LEF (20 mg daily). Follow-up was 12 months. CAG repeat polymorphism was determined using polymerase chain reaction (PCR) and subsequent fragment analysis by capillary electrophoresis.

Results

Analysis revealed no statistically significant associations between CAG repeat polymorphism in the AR gene and improvement of disease activity parameters: erythrocyte sedimentation rate, serum C-reactive protein, patient’s global assessment of disease activity on a visual analog scale (VAS), disease activity score of 28 joints (DAS28), and swollen and tender joint count.

Conclusion

Our results suggest no correlation between CAG repeat polymorphism in the AR gene and response to treatment with LEF in women with RA.

Anti-inflammatory and Anti-arthritic Effects of a Novel Leflunomide Analogue, UTL-5b (GBL-5b)

Rheumatoid arthritis (RA) is a common disease characterized by chronic inflammation and irreversible destruction of articular cartilage and bone. In this report, we examined the anti-inflammatory and anti-arthritic effects of a novel leflunomide analogue, UTL-5b (also known as GBL-5b), for potential RA treatment. Using a carrageenan-induced edema study in rats, UTL-5b exhibited a better anti-inflammatory effect as compared with leflunomide and its metabolite. The chronic efficacy of UTL-5b was examined using type II collagen-induced arthritis (CIA) mouse model. UTL-5b exerted an anti-arthritic effect in a dose-dependant manner with mice given 30 mg/kg exhibiting amelioration of disease early in the trial, but losing statistical significance over time. In contrast, mice treated with 60 mg/kg showed reduced clinical disease parameters early in the trial and these effects were sustained over the ten week trial period. Mechanistic studies indicate that UTL-5b is an inhibitor of TNF-α production in vivo. Oral administration of UTL-5b prior to i.p. injection with lethal dose of lipopolysaccharide (LPS)/D-galactosamine markedly reduced the levels of serum TNF-α and increased survival rates of animals from septic shock-induced death. Acute toxicity study using mice receiving increasing doses of UTL-5b showed that no animals were killed by UTL-5b at 2,000 mg/kg (LD(50) >2,000 mg/kg). Our studies show that UTL-5b represents a novel anti-inflammatory and anti-arthritic agent with potential therapeutic application for RA treatment.

Development of a framework for reporting health service models for managing rheumatoid arthritis

The purpose of this study was to develop a framework for reporting health service models for managing rheumatoid arthritis (RA). We conducted a search of the health sciences literature for primary studies that described interventions which aimed to improve the implementation of health services in adults with RA. Thereafter, a nominal group consensus process was used to synthesize the evidence for the development of the reporting framework. Of the 2,033 citations screened, 68 primary studies were included which described 93 health service models for RA. The origin and meaning of the labels given to these health service delivery models varied widely and, in general, the reporting of their components lacked detail or was absent. The six dimensions underlying the framework for reporting RA health service delivery models are: (1) Why was it founded? (2) Who was involved? (3) What were the roles of those participating? (4) When were the services provided? (5) Where were the services provided/received? (6) How were the services/interventions accessed and implemented, how long was the intervention, how did individuals involved communicate, and how was the model supported/sustained? The proposed framework has the potential to facilitate knowledge exchange among clinicians, researchers, and decision makers in the area of health service delivery. Future work includes the validation of the framework with national and international stakeholders such as clinicians, health care administrators, and health services researchers.

Improving healthcare consumer effectiveness: an Animated, Self-serve, Web-based Research Tool (ANSWER) for people with early rheumatoid arthritis

BACKGROUND

People with rheumatoid arthritis (RA) should use DMARDs (disease-modifying anti-rheumatic drugs) within the first three months of symptoms in order to prevent irreversible joint damage. However, recent studies report the delay in DMARD use ranges from 6.5 months to 11.5 months in Canada. While most health service delivery interventions are designed to improve the family physician's ability to refer to a rheumatologist and prescribe treatments, relatively little has been done to improve the delivery of credible, relevant, and user-friendly information for individuals to make treatment decisions. To address this care gap, the Animated, Self-serve, Web-based Research Tool (ANSWER) will be developed and evaluated to assist people in making decisions about the use of methotrexate, a type of DMARD. The objectives of this project are: 1) to develop ANSWER for people with early RA; and 2) to assess the extent to which ANSWER reduces people's decisional conflict about the use of methotrexate, improves their knowledge about RA, and improves their skills of being 'effective healthcare consumers'.

METHODS/DESIGN

Consistent with the International Patient Decision Aid Standards, the development process of ANSWER will involve: 1.) creating a storyline and scripts based on the best evidence on the use of methotrexate and other management options in RA, and the contextual factors that affect a patient's decision to use a treatment as found in ERAHSE; 2.) using an interactive design methodology to create, test, analyze and refine the ANSWER prototype; 3.) testing the content and user interface with health professionals and patients; and 4.) conducting a pilot study with 51 patients, who are diagnosed with RA in the past 12 months, to assess the extent to which ANSWER improves the quality of their decisions, knowledge and skills in being effective consumers.

DISCUSSION

We envision that the ANSWER will help accelerate the dissemination of knowledge and skills necessary for people with early RA to make informed choices about treatment and to manage their health. The latest in animation and online technology will ensure ANSWER fills a knowledge translation gap, focusing on the next generation of people living with RA.

Description and mapping of the resistance of DBA/2 mice to TNF-induced lethal shock

In our search for genes that inhibit the inflammatory effects of TNF without diminishing its antitumor capacities we found that, compared with C57BL/6 mice, DBA/2 mice exhibit a dominant resistance to TNF-induced lethality. Tumor-bearing (C57BL/6 x DBA/2)(BXD)F(1) mice completely survived an otherwise lethal TNF/IFN-gamma-antitumor therapy with complete regression of the tumor. This was not the case for C57BL/6 mice. Genetic linkage analysis revealed that TNF resistance is linked to a major locus on distal chromosome 6 and a minor locus on chromosome 17. Compared with littermate controls, chromosome substitution mice carrying a DBA/2 chromosome 6 in a C57BL/6 background were significantly protected against TNF and TNF/IFN-gamma, albeit less so than DBA/2 mice. Definition of a critical region of 13 Mb on chromosome 6 was the highest mapping resolution obtained. Further analysis of candidate genes may provide a powerful tool to control TNF-induced pathologies in humans.

Vitamin D receptor gene polymorphism in rheumatoid arthritis and associated osteoporosis

Rheumatoid arthritis (RA) is commonly associated with decreased bone mineral density (BMD) due to numerous factors. BsmI polymorphism of the vitamin D receptor (VDR) gene has been implicated in the pathogenesis of osteoporosis. Vitamin D has several immunomodulatory effects and thus may play a role in the course of arthritis. However, little data is available on the possible relationship between RA and VDR gene polymorphisms. In this study, the frequency of BsmI polymorphism genotypes were compared with that found in other countries. In this study, 64 RA patients and 40 healthy controls were tested for VDR gene BsmI polymorphism genotypes. Frequencies of B and b alleles were associated with markers of bone metabolism and RA. Among control subjects, the frequency of the BB genotype is relatively high (27.5%). In RA with secondary osteopenia/osteoporosis the BB genotype was more rare, the bb was more common than in control subjects. Markers of bone metabolism were associated with the B allele. RA patients carrying the B allele had lower BMD and increased bone loss over 1 year. The B allele was also correlated with increased osteoclast and osteoblast function, as determined by the assessment of biochemical markers of bone metabolism. Rheumatoid factor titer, which is an independent marker for disease progression in RA, was higher in bb patients. Our data suggest, that the imbalance in B and b allele expression may be involved in the pathogenesis of RA-associated osteoporosis. The possible involvement of vitamin D and VDR gene polymorphisms in the development and progression of RA needs further elucidation.

Gaps in care for rheumatoid arthritis: A population study

OBJECTIVE

Treatment guidelines for rheumatoid arthritis (RA) now recommend early, aggressive, and persistent use of disease-modifying antirheumatic drugs (DMARDs) to prevent joint damage in all people with active inflammation, and evaluation by a rheumatologist, when possible. This research assesses whether care for RA, at a population level, is consistent with current treatment guidelines.

METHODS

Using administrative billing data from the Ministry of Health in 1996-2000, all prevalent RA cases in British Columbia, Canada were identified. Data were obtained on all medications and all provincially-funded health care services.

RESULTS

We identified 27,710 RA cases, yielding a prevalence rate of 0.76%, consistent with epidemiologic studies. DMARD use was inappropriately low. Only 43% of the entire RA cohort received a DMARD at least once over 5 years, and 35% over 2 years. When used, DMARDs were started in a timely fashion, but were not used consistently. Care by a rheumatologist increased DMARD use 31-fold. Yet, only 48% and 34% saw a rheumatologist over 5 and 2 years, respectively. DMARD use was significantly more frequent, persistent, and more often used as combination therapy with continuous rheumatologist care. DMARDs were used by 84% and 73%, 40%, and 10% of people followed by rheumatologists continuously and intermittently, internists, and family physicians, respectively (P < 0.001). NSAID use, physiotherapy, and orthopedic surgeries were similar across these 4 care groups.

CONCLUSION

RA care in the British Columbia population was not consistent with current treatment guidelines. Efforts to educate family physicians and consumers about the shift in RA treatment paradigms and to improve access to rheumatologists are needed.

Retroviral gene therapy of collagen-induced arthritis by local delivery of IL-4

Rheumatoid arthritis (RA) is an autoimmune arthritis, for which treatment options remain limited. This study investigated the potential role of adoptive cellular gene therapy as a novel means for treating the RA animal model collagen-induced arthritis (CIA). Adoptive transfer of antigen-specific T-cell hybridomas retrovirally transduced to express IL-4 1 day before booster immunization significantly reduced the number of inflamed joints. Cell transfer after clinical onset of disease had no therapeutic effect. Bioluminescence imaging showed that the hybridomas migrated to the inflamed joints, thus delivering the regulatory protein locally at the site of inflammation. The homing was, at least in part, due to chemotaxis in response to proinflammatory chemokines that are expressed in inflamed joints. There were no significant changes in the cytokine milieu of the draining lymph nodes, nor in the systemic levels of anti-collagen antibodies in treated mice. We conclude that the beneficial clinical effects observed in our model were most likely based on the local action(s) of IL-4 in the inflamed joints and that the local delivery (and effects) of regulatory cytokines, like IL-4, constitutes a novel and effective method of preventing organ-specific autoimmune disease and of minimizing systemic adverse effects.

Distinct functions of COX-1 and COX-2

The enzymes that convert arachidonic acid to prostaglandin H2 are named cyclooxygenase-1 (COX-1) and COX-2. The properties of COX-1 are different from those of COX-2. It was originally thought that the function of COX-1 was involved in physiological phenomena, whereas that of COX-2 was involved in various pathologies. However, studies with COX-2 knockout mouse suggest that COX-2 also plays important roles in development and homeostasis. This chapter focuses on the distinct functions of COX-1 and COX-2.