Post-traumatic stress disorder and serum cytokine and chemokine concentrations in patients with rheumatoid arthritis✰.

OBJECTIVE: Although post-traumatic stress disorder (PTSD) is identified as a risk factor in the development of rheumatoid arthritis (RA), associations of PTSD with disease progression are less clear. To explore whether PTSD might influence disease-related measures of systemic inflammation in RA, we compared serum cytokine/chemokine (cytokine) concentrations in RA patients with and without PTSD. METHODS: Participants were U.S. Veterans with RA and were categorized as having PTSD, other forms of depression/anxiety, or neither based on administrative diagnostic codes. Multiplex cytokines were measured using banked serum. Associations of PTSD with cytokine parameters (including a weighted cytokine score) were assessed using multivariable regression, stratified by anti-CCP status and adjusted for age, sex, race, and smoking status. RESULTS: Among 1,460 RA subjects with mean (SD) age of 64 (11) years and disease duration of 11 (11) years, 91% were male, 77% anti-CCP positive, and 80% ever smokers. Of these, 11.6% had PTSD, 23.7% other depression/anxiety, and 64.7% had neither. PTSD, but not depression/anxiety, was associated with a higher cytokine score and number of high-concentration analytes in adjusted models, though this was limited to anti-CCP positive subjects. PTSD was associated with heightened expression of several individual cytokines including IL-1ß, IL-2, IL-4, IL-5, IL-6, IL-7, IL-10, IL-12, IL-17, IFN-γ, GM-CSF, MCP-1, and TNF-α. CONCLUSION: Anti-CCP positive RA patients with PTSD have higher serum cytokine concentrations than those without PTSD, demonstrating that systemic inflammation characteristic of RA is heightened in the context of this relatively common psychiatric comorbidity.

A comparison of electronic and manual fracture risk assessment tools in screening elderly male US veterans at risk for osteoporosis.

This study compares four screening tools in their ability to predict osteoporosis. We found that there was no significant difference between the tools. These results provide support for the use of automated screening tools which work in conjunction with the electronic medical record and help improve screening rates for osteoporosis. INTRODUCTION: The purpose of this study is to compare the performance of four fracture risk assessment tools (FRATs) in identifying osteoporosis by bone mineral density (BMD) T-score: Veterans Affairs Fracture Absolute Risk Assessment Tool (VA-FARA), World Health Organization's Fracture Risk Assessment Tool (FRAX), electronic FRAX (e-FRAX), and Osteoporosis Self-Assessment Screening Tool (OST). METHODS: We performed a cross-sectional analysis of all patients enrolled in the VA Salt Lake City bone health team (BHT) who had completed a DXA scan between February 1, 2012, and February 1, 2013. DXA scan results were obtained by chart abstraction. For calculation of FRAX, osteoporosis risk factors were obtained from a screening questionnaire completed prior to DXA. For VA-FARA and e-FRAX, risk factors were derived from the electronic medical record (EMR). Clinical risk scores were calculated and compared against the gold standard of DXA-based osteoporosis. Sensitivity, specificity, and predictive values were calculated. Receiver operator characteristic (ROC) curves were plotted, and areas under the curve (AUC) were compared. RESULTS: A cohort of 463 patients met eligibility criteria (mean age 80.4 years). One hundred twelve patients (24%) had osteoporosis as defined by DXA T-score ≤-2.5. Sensitivity, specificity, and predictive values were calculated. ROC statistics were compared and did not reach statistical significance difference between FRATs in identifying DXA-based osteoporosis. CONCLUSIONS: Our study suggests that all FRATs tested perform similarly in identifying osteoporosis among elderly, primarily Caucasian, male veterans. If these electronic screening methods perform similarly for fracture outcomes, they could replace manual FRAX and thus improve efficiency in identifying individuals who should be sent for DXA scan.

Cost-effectiveness of training rural providers to identify and treat patients at risk for fragility fractures.

UNLABELLED: This is a cost-effectiveness analysis of training rural providers to identify and treat osteoporosis. Results showed a slight cost savings, increase in life years, increase in treatment rates, and decrease in fracture incidence. However, the results were sensitive to small differences in effectiveness, being cost-effective in 70 % of simulations during probabilistic sensitivity analysis. INTRODUCTION: We evaluated the cost-effectiveness of training rural providers to identify and treat veterans at risk for fragility fractures relative to referring these patients to an urban medical center for specialist care. The model evaluated the impact of training on patient life years, quality-adjusted life years (QALYs), treatment rates, fracture incidence, and costs from the perspective of the Department of Veterans Affairs. METHODS: We constructed a Markov microsimulation model to compare costs and outcomes of a hypothetical cohort of veterans seen by rural providers. Parameter estimates were derived from previously published studies, and we conducted one-way and probabilistic sensitivity analyses on the parameter inputs. RESULTS: Base-case analysis showed that training resulted in no additional costs and an extra 0.083 life years (0.054 QALYs). Our model projected that as a result of training, more patients with osteoporosis would receive treatment (81.3 vs. 12.2 %), and all patients would have a lower incidence of fractures per 1,000 patient years (hip, 1.628 vs. 1.913; clinical vertebral, 0.566 vs. 1.037) when seen by a trained provider compared to an untrained provider. Results remained consistent in one-way sensitivity analysis and in probabilistic sensitivity analyses, training rural providers was cost-effective (less than $50,000/QALY) in 70 % of the simulations. CONCLUSIONS: Training rural providers to identify and treat veterans at risk for fragility fractures has a potential to be cost-effective, but the results are sensitive to small differences in effectiveness. It appears that provider education alone is not enough to make a significant difference in fragility fracture rates among veterans.

Folic acid pathway single nucleotide polymorphisms associated with methotrexate significant adverse events in United States veterans with rheumatoid arthritis.

OBJECTIVES: Methotrexate (MTX) is the cornerstone medication in the treatment of rheumatoid arthritis (RA). We examined whether single nucleotide polymorphisms (SNPs) in enzymes of the folic acid pathway (folylpoly-gamma-glutamate synthetase [FPGS], gamma-glutamyl hydrolase [GGH], and methylenetetrahydrofolate reductase [MTHFR]) associate with significant adverse events (SigAE). METHODS: Patients (n=319) enrolled in the Veterans Affairs RA (VARA) registry taking MTX were genotyped for HLA-DRB1-SE and the following SNPs: FPGS (rs7033913, rs10760503, rs10106), GGH (12548933, rs7010484, rs4617146, rs719235, rs11988534), MTHFR (rs1801131, rs1801133). AE were abstracted from the medical record using a structured instrument. SigAE were defined as an AE leading to MTX discontinuation. Covariates included: age, gender, race, RA antibody status, tobacco, RA disease duration between diagnosis and MTX course, Charlson-Deyo comorbidity index, glucocorticoids, use of prior RA medications, and mean 4-variable disease activity score. Cox regression was performed to determine factors associated with time-to-SigAE. A p-value ≤ 0.005 established significance in the final model. RESULTS: The presence of ≥ 1 copy of the minor allele in MTHFR rs1801131 was associated with an increased hazard ratio (HR) of SigAE (HR 3.05, 95% CI 1.48-6.29, p-value 0.003 and HR 3.88, 95% CI 1.62-9.28, p-value 0.002 for heterozygotes and homozygotes for the minor allele, respectively). An interaction term, between FPGS rs7033913 heterozygotes and GGH rs11988534 homozygotes for the minor allele, had a p-value <0.0001. CONCLUSIONS: RA subjects taking MTX may have decreased time-to-SigAE with ≥ 1 copy of the minor allele in MTHFR rs1801131. Further investigation is warranted, as these SNPs may indicate susceptibility to MTX toxicity.

Risk of hospitalized bacterial infections associated with biologic treatment among US veterans with rheumatoid arthritis.

OBJECTIVE: The comparative risk of infection associated with non-anti-tumor necrosis factor (anti-TNF) biologic agents is not well established. Our objective was to compare risk for hospitalized infections between anti-TNF and non-anti-TNF biologic agents in US veterans with rheumatoid arthritis (RA). METHODS: Using 1998-2011 data from the US Veterans Health Administration, we studied RA patients initiating rituximab, abatacept, or anti-TNF therapy. Exposure was based upon days supplied (injections) or usual dosing intervals (infusions). Treatment episodes were defined as new biologic agent use. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) for hospitalization for a bacterial infection were estimated from Cox proportional hazards models, adjusting for potential confounders. RESULTS: Among 3,152 unique RA patients contributing 4,158 biologic treatment episodes to rituximab (n = 596), abatacept (n = 451), and anti-TNF agents (n = 3,111), the patient mean age was 60 years and 87% were male. The most common infections were pneumonia (37%), skin/soft tissue (22%), urinary tract (9%), and bacteremia/sepsis (7%). Hospitalized infection rates per 100 person-years were 4.4 (95% CI 3.1-6.4) for rituximab, 2.8 (95% CI 1.7-4.7) for abatacept, and 3.0 (95% CI 2.5-3.5) for anti-TNF. Compared to etanercept, the adjusted rate of hospitalized infection was not different for adalimumab (HR 1.4, 95% CI 0.9-2.2), abatacept (HR 1.1, 95% CI 0.6-2.1), or rituximab (HR 1.4, 0.8-2.6), although it was increased for infliximab (HR 2.3, 95% CI 1.3-4.0). Infection risk was greater for those taking prednisone >7.5 mg/day (HR 1.8, 95% CI 1.3-2.7) and in the highest quartile of C-reactive protein (HR 2.3, 95% CI 1.4-3.8) and erythrocyte sedimentation rate (HR 4.1, 95% CI 2.3-7.2) compared to the lowest quartile. CONCLUSION: In older, predominantly male US veterans with RA, the risk of hospitalized bacterial infections associated with rituximab or abatacept was similar to etanercept.

Poor to modest agreement between rheumatoid arthritis response measures in clinical practice.

OBJECTIVE: To evaluate the agreement among several rheumatoid arthritis (RA) response measures in a clinical setting. METHODS: 529 patients with RA were seen at 2 regular visits where the following response measures were determined: ACR-20, EULAR good or moderate (EULAR-GM), Simplified Disease Activity Index moderate (SDAI-M), Clinical DAI moderate (CDAI-M), and Patient Reported Outcomes Index-M 20 (PRO-IM-20). Each measure was modified to include a "worse" response, i.e. the inverse of the respective guidelines for a positive improvement response.Introduced for comparison was the Real-time Assessment of Disease Activity in Rheumatoid Arthritis (RADARA), a response measure that registers improvement if the patient's tender and swollen joint counts and HAQ score all improve and worsening if all three increase. Contingency tables comparing the three responses (worse, no change, and improvement) along with Cohen's kappa were calculated. RESULTS: The mean (SD) baseline characteristics of the patients included: age 66.5 (10.7) years, RA duration 12.9 (11.0) years, 91.3% male, 84.1% rheumatoid factor positive, and a Disease Activity Score-28 of 3.5 (1.3). The percentage of patients who improved/worsened were as follows: ACR-20 4.7/9.1, EULAR-GM 23.4/26.3, SDAI-M 16.1/20.6, CDAI-M 16.3/20.0, PRO-IM-20 22.5/34.4, and RADARA 7.0/11.5. Agreement (kappa) was poor to slight (

Benefit/risk of leflunomide in rheumatoid arthritis.

Leflunomide was first shown to have disease-modifying properties in a rat model of adjuvant-induced arthritis. Leflunomide has been subsequently used with success in several animal models of tissue and organ allograft and of autoimmune disease including collagen- and adjuvant-induced arthritis, interstitial nephritis, myasthenia gravis, and systemic lupus erythematosus. Based on its success as an immunosuppressive agent in these models, leflunomide was tested for the treatment of rheumatoid arthritis (RA).

Genetic factors involved in central nervous system/immune interactions.

Analysis of several inbred rat strains has led us to hypothesize that HPA axis abnormalities may contribute, in part, to susceptibility to both autoimmune disease and addiction. In this article we review the evidence for this hypothesis and describe our ongoing efforts to genetically characterize these traits. We have mapped the locations of 23 loci that regulate autoimmune disease in rats, and are currently constructing QTL congenic lines in which a genomic region from the resistant strain is transferred to the susceptible strain or vice versa. These QTL congenic lines will be valuable to test whether genes encoding autoimmune regulation also control neuroendocrine traits. Further genetic dissection and identification of the underlying genes will be necessary to infer a mechanistic link between autoimmune and neuroendocrine traits.

Two-year, blinded, randomized, controlled trial of treatment of active rheumatoid arthritis with leflunomide compared with methotrexate. Utilization of Leflunomide in the Treatment of Rheumatoid Arthritis Trial Investigator Group.

OBJECTIVE: Three 6-12-month, double-blind, randomized, controlled trials have shown leflunomide (LEF; 20 mg/day, loading dose 100 mg x 3 days) to be effective and safe for the treatment of rheumatoid arthritis (RA). This analysis of the North American trial assessed whether the clinical benefit evident at month 12 was sustained over 24 months of treatment with LEF as compared with the efficacy and safety of methotrexate (MTX), an equivalent disease-modifying antirheumatic drug, at 24 months. METHODS: The year-2 cohort, comprising patients continuing into the second year of treatment with > or = 1 dose of study medication and > or = 1 followup visit after week 52, consisted of 235 patients (LEF n = 98; placebo n = 36; MTX n = 101). The mean (+/- SD) maintenance dose of LEF was 19.6 +/- 1.99 mg/day in year 2 and that of MTX was 12.6 +/- 4.69 mg/week. Statistical analyses used an intent-to-treat (ITT) approach. Statistical comparisons of the active treatments only were prospectively defined in the protocol. RESULTS: In total, 85% and 79% of LEF and MTX patients, respectively, who entered year 2 completed 24 months of treatment. From month 12 to month 24, the American College of Rheumatology improvement response rates of > or = 20% (LEF 79% versus MTX 67%; P = 0.049), > or = 50% (LEF 56% versus MTX 43%; P = 0.053), and > or = 70% (LEF 26% versus MTX 20%; P = 0.361) were sustained in both of the active treatment groups. The mean change in total Sharp radiologic damage scores at year 2 compared with year 1 and baseline (LEF 1.6 versus MTX 1.2) showed statistically equivalent sustained retardation of radiographic progression in the active treatment groups. Maximal improvements evident at 6 months in the Health Assessment Questionnaire (HAQ) disability index (HAQ DI) and the physical component score of the Medical Outcomes Survey 36-item short form were sustained over 12 months and 24 months; improvement in the HAQ DI with LEF4(-0.60) was statistically significantly superior to that with MTX (-0.37) at 24 months (P = 0.005). Over 24 months in the ITT cohort, serious treatment-related adverse events were reported in 1.6% of the LEF-treated patients and 3.7% of the MTX-treated patients. Frequently reported adverse events included upper respiratory tract infections, diarrhea, nausea and vomiting, rash, reversible alopecia, and transient liver enzyme elevations. CONCLUSION: The safety and efficacy of LEF and MTX were maintained over the second year of this 2-year trial. Both active treatments retarded radiographic progression over 24 months. LEF was statistically significantly superior to MTX in improving physical function as measured by the HAQ DI over 24 months of treatment. Results indicate that LEF is a safe and effective initial treatment for active RA, with clinical benefit sustained over 2 years of treatment without evidence of new or increased toxicity.

Efficacy of cyclooxygenase-2-specific inhibitors.

Conventional nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit both cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2). The clinical efficacy of NSAIDs is primarily related to the inhibition of COX-2 activity, whereas much of the toxicity, particularly gastrointestinal toxicity, is related to COX-1 inhibition. In vitro and in vivo assays indicate that both COX-2-specific inhibitors and conventional NSAIDs are equally effective in inhibiting COX-2, suggesting that the clinical efficacy of COX-2-specific inhibitors should be similar to that of conventional NSAIDs. Multiple studies in patients with osteoarthritis, rheumatoid arthritis, and acute pain have now confirmed that the clinical efficacy of COX-2-specific inhibitors is similar to that of conventional NSAIDs.

Genetic dissection of collagen-induced arthritis in Chromosome 10 quantitative trait locus speed congenic rats: evidence for more than one regulatory locus and sex influences.

Rat Chromosome 10 (RNO10) harbors Cia5, a non-MHC quantitative trait locus (QTL) that regulates the severity of type II collagen-induced arthritis (CIA) in DAxF344 and DAxBN F2 rats. CIA is an animal model with many features that resemble rheumatoid arthritis. To facilitate analysis of Cia5 independently of the other CIA regulatory loci on other chromosomes, DA recombinant QTL speed congenic rats, DA.F344(Cia5), were generated. These QTL congenic rats have a large chromosomal segment containing Cia5 (interval size < or =80.1 cM) from CIA-resistant F344 rats introgressed into their genome. Phenotypic analyses of these rats for susceptibility and severity of CIA confirmed that Cia5 is an important disease-modifying locus. CIA severity was significantly lower in the Cia5 congenic rats than in DA controls. We also generated DA Cia5 speed sub-congenic rats, DA.F344(Cia5a), which had a smaller segment of the F344 genome, Cia5a, comprising only the distal q-telomeric end (interval size < or = 22.5 cM) of Cia5, introgressed into their genome. DA.F344(Cia5a) sub-congenic rats also exhibited reduced CIA disease severity compared with the parental DA rats. The regulatory effects in both congenic strains were sex influenced. The disease-ameliorating effect of the larger fragment, Cia5, was greater in males than in females, but the effect of the smaller fragment, Cia5a, was greater in females. We also present an improved genetic linkage map covering the Cia5/Cia5a region, which we have integrated with two rat radiation hybrid maps. Comparative homology analysis of this genomic region with mouse and human chromosomes was also undertaken. Regulatory loci for multiple autoimmune/inflammatory diseases in rats (RNO10), mice (MMU11), and humans (HSA17 and HSA5q23-q31) map to chromosomal segments homologous to Cia5 and Cia5a.

Genetic dissection of a rat model for rheumatoid arthritis: significant gender influences on autosomal modifier loci.

Rheumatoid arthritis (RA) is a common, chronic, autoimmune, inflammatory disease that is influenced by genetic factors including gender. Many studies suggest that the genetic risk for RA is determined by the MHC, in particular class II alleles with a 'shared epitope' (SE), and multiple non-MHC loci. Other studies indicate that RA and other autoimmune diseases, in particular insulin-dependent diabetes mellitus (IDDM) and autoimmune thyroid disease (ATD), share genetic risk factors. Rat collagen-induced arthritis (CIA) is an experimental model with many features that resemble RA. The spontaneous diabetes-resistant bio-breeding rat, BB(DR), is of interest because it is susceptible to experimentally induced CIA, IDDM and ATD, and it has an SE in its MHC class II allele. To explore the genetics of CIA, including potential gender influences and the genetic relationships between CIA and other autoimmune diseases, we conducted a genome-wide scan for CIA regulatory loci in the F(2) progeny of BB(DR) and CIA-resistant BN rats. We identified 10 quantitative trait loci (QTLs), including 5 new ones (Cia15, Cia16*, Cia17, Cia18* and Cia19 on chromosomes 9, 10, 18 and two on the X chromosome, respectively), that regulated CIA severity. We also identified four QTLs, including two new ones (Ciaa4* and Ciaa5* on chromosomes 4 and 5, respectively), that regulated autoantibody titer to rat type II collagen. Many of these loci appeared to be gender influenced, and most co-localized with several other autoimmune trait loci. Our data support the view that multiple autoimmune diseases may share genetic risk factors, and suggest that many of these loci are gender influenced.

Identification of four new quantitative trait loci regulating arthritis severity and one new quantitative trait locus regulating autoantibody production in rats with collagen-induced arthritis.

OBJECTIVE: Collagen-induced arthritis (CIA) is a polygenic model of experimentally induced autoimmunity and chronic joint inflammation. This study maps genetic loci that regulate CIA susceptibility in DA/Bkl (DA) and BN/SsNHsd (BN) rats. METHODS: Genome scans covering chromosomes 1-20 and interval mapping techniques using 159 simple sequence-length polymorphism markers were used to identify quantitative trait loci (QTLs) that regulate CIA in (DA x BN)F2 hybrids. Serum antibody titers to type II collagen were determined by enzyme-linked immunosorbent assay. RESULTS: DA rats were high responders to porcine type II collagen (PII) and developed severe CIA (100%). BN rats were low responders to PII and resistant to CIA (0%). BN genes strongly repressed PII-induced CIA. Only 12% of (DA x BN)F1 rats (7 of 60) and 31% of (DA x BN)F2 rats (307 of 1,004) developed CIA. Three new QTLs (Cia11, Cia12, and Cia13) with significant logarithm of odds (LOD) scores of 5.6, 4.6, and 4.5, respectively, plus a suggestive QTL (Cia14*, LOD 3.0) regulating arthritis severity were identified on chromosomes 3, 12, 4, and 19. A new QTL, Ciaa3, associating with anticollagen antibody titer (antibody to PII LOD 6.5; antibody to rat type II collagen LOD 5.2) mapped to chromosome 9. Of 10 CIA QTLs previously identified in (DA x F344) and (DA x ACI) rats, only Cia1 in the major histocompatibility complex and a region coincident to Cia5 on chromosome 10 (LOD >8.0) influenced CIA severity in (DA x BN)F2 rats. CONCLUSION: Since CIA exhibits many of the pathologic features of rheumatoid arthritis, the data indicate that the variety of genetic elements regulating human autoimmune and rheumatic diseases may be much larger and more varied than originally envisioned.

Rofecoxib, a specific inhibitor of cyclooxygenase 2, with clinical efficacy comparable with that of diclofenac sodium: results of a one-year, randomized, clinical trial in patients with osteoarthritis of the knee and hip. Rofecoxib Phase III Protocol 035 Study Group.

OBJECTIVE: To compare the clinical efficacy of rofecoxib, a specific inhibitor of cyclooxygenase 2 (COX-2), with that of diclofenac in patients with osteoarthritis (OA) and to evaluate the safety and tolerability of rofecoxib. METHODS: We performed a randomized, double-blind, active comparator-controlled trial in 784 adults with OA of the knee or hip. Patients were randomized to 1 of 3 treatment groups: 12.5 mg of rofecoxib once daily, 25 mg of rofecoxib once daily, and 50 mg of diclofenac 3 times daily. Clinical efficacy and safety were evaluated over a 1-year continuous treatment period. RESULTS: Rofecoxib at dosages of 12.5 and 25 mg demonstrated efficacy that was clinically comparable to that of diclofenac, as assessed by all 3 primary end points according to predefined comparability criteria. Results from secondary end points were consistent with those of the primary end points. There were small statistical differences favoring diclofenac for 2 of the end points. All treatments were well tolerated. CONCLUSION: Rofecoxib was well tolerated and provided efficacy that was clinically comparable, according to predefined statistical criteria, to that of 150 mg of diclofenac per day in this 1-year study. Specific inhibition of COX-2 provided therapeutic efficacy in OA.

An integrated genetic linkage map with 1,137 markers constructed from five F2 crosses of autoimmune disease-prone and -resistant inbred rat strains.

The rat (Rattus norvegicus) is an important experimental model for many human diseases including arthritis, diabetes, and other autoimmune and chronic inflammatory diseases. The rat genetic linkage map, however, is less well developed than those of mouse and human. Integrated rat genetic linkage maps have been previously reported by Pravenec et al. (1996, Mamm. Genome 7: 117-127) (500 markers mapped in one cross), Bihoreau et al. (1997, Genome Res. 7: 434-440) (767 markers mapped in three crosses), Wei et al. (1998, Mamm. Genome 9: 1002-1007) (562 markers mapped in two crosses), Brown et al. (1998, Mamm. Genome 9: 521-530) (678 markers mapped in four crosses), and Nordquist et al. (1999, Rat Genome 5: 15-20) (330 markers mapped in two crosses). The densest linkage map combined with a radiation hybrid map, reported by Steen et al. (1999, Genome Res. 9: AP1-AP8), includes 4736 markers mapped in two crosses. Here, we present an integrated linkage map with 1137 markers. We have constructed this map by genotyping F2 progeny of five crosses: F344/NHsd x LEW/NHsd (673 markers), DA/Bkl x F344/NHsd (531 markers), BN/SsN x LEW/N (714 markers), DA/Bkl x BN/SsNHsd (194 markers), and DA/Bkl x ACI/SegHsd (245 markers). These inbred rat strains vary in susceptibility/resistance to multiple autoimmune diseases and are used extensively for many types of investigation. The integrated map includes 360 loci mapped in three or more crosses. The map contains 196 new SSLP markers developed by our group, as well as many SSLP markers developed by other groups. Two hundred forty genes are incorporated in the map. This integrated map should allow comparison of rat genetic maps from different groups and thereby facilitate genetic studies of rat autoimmune and related disease models.

Susceptibility to autoimmune disease and drug addiction in inbred rats. Are there mechanistic factors in common related to abnormalities in hypothalamic-pituitary-adrenal axis and stress response function?

DA and LEW inbred rats are extraordinarily susceptible to a wide range of experimental autoimmune diseases. These diseases include rheumatoid arthritis models such as collagen-induced arthritis (CIA) and adjuvant-induced arthritis (AIA), multiple sclerosis models such as myelin-basic-protein (MBP)-induced experimental autoimmune encephalomyelitis (MBP-EAE), and autoimmune uveitis models such as retinal S antigen (SAG) and interphotoreceptor-retinoid-binding-protein (IRBP)-induced experimental autoimmune uveitis (SAG-EAU and IRBP-EAU, respectively). DA and LEW rats are also addiction-prone to various drugs of abuse, such as cocaine. Moreover, they exhibit a variety of behavioral and biochemical characteristics that appear to be related to their susceptibility to addiction. By contrast, F344 and BN rats show quite different phenotypes. They are relatively resistant to CIA, AIA, MBP-EAE, SAG-EAU, and IRBP-EAU, and they are relatively resistant to addiction. Interestingly, both DA and LEW rats, in contrast to F344 and BN rats, have abnormalities in hypothalamic-pituitary-adrenal (HPA) axis function. For example, circadian production of corticosteroids is very abnormal in DA and LEW rats; that is, they exhibit minimal circadian variation in corticosterone levels. Since corticosteroids potentially have significant influences on immune function and autoimmune disease susceptibility and may also influence sensitivity to drugs of abuse, we have begun to dissect genetic control of these various phenotypic differences, focusing initially on the regulation of autoimmune disease expression. Using genomewide scanning techniques involving F2 crosses of DA x F344 (CIA and AIA), DA x BN (CIA), and LEW x F344 [IRBP-EAU and streptococcal-cell-wall arthritis (SCWA)], we have identified, to date, 14 genomic regions [quantitative trait loci (QTL)] that regulate disease expression in these crosses. Development and analysis of QTL-congenic rats involving these loci are in progress and should permit us to address the relationships among autoimmune disease susceptibility, drug addiction, and HPA axis and stress response function. These initial data, however, indicate that the genetic control of the autoimmune disease traits is highly complex.

Rofecoxib: a specific cyclooxygenase inhibitor.

Rofecoxib is a new specific cyclooxygenase-2 inhibitor. The efficacy of rofecoxib has been established in the treatment of osteoarthritis, rheumatoid arthritis and acute pain. Rofecoxib has been approved in the United States for the treatment of osteoarthritis and acute pain. Endoscopically proven gastrointestinal ulceration is much less with rofecoxib than standard nonsteroidal antiinflammatory drugs (NSAIDs) and the ulceration rate with rofecoxib is similar to that seen with placebo. Rofecoxib appears to provide clinical benefit equivalent to standard NSAIDs with less toxicity.

The Prosorba column for treatment of refractory rheumatoid arthritis: a randomized, double-blind, sham-controlled trial.

OBJECTIVE: To evaluate the efficacy and safety of the Prosorba column as a treatment for rheumatoid arthritis (RA) in patients with active and treatment-resistant (refractory) disease. METHODS: A sham-controlled, randomized, double-blind, multicenter trial of Prosorba versus sham apheresis was performed in patients with RA who had failed to respond to treatment with methotrexate or at least 2 other second-line drugs. Patients received 12 weekly treatments with Prosorba or sham apheresis, with efficacy evaluated 7-8 weeks after treatment ended. Patients were characterized as responders if they experienced improvement according to the American College of Rheumatology (ACR) response criteria at the efficacy time point. A data safety monitoring board (DSMB) evaluated interim analyses for the possibility of early completion of the trial. RESULTS: Patients in the trial had RA for an average of 15.5 years (range 1.7-50.6) and had failed an average of 4.2 second-line drug treatments prior to entry. After the completion of treatment of 91 randomized patients, the DSMB stopped the trial early due to successful outcomes. Of the 47 patients in the Prosorba arm, 31.9% experienced ACR-defined improvement versus 11.4% of the 44 patients in the sham-treated arm (P = 0.019 after adjustment for interim analysis). When results from 8 additional patients, who had completed blinded treatments at the time of DSMB action, were added to the analysis (n = 99), results were unchanged. The most common adverse events were a short-term flare in joint pain and swelling following treatment, a side effect that occurred in most subjects at least once in both treatment arms. Other side effects, although common, occurred equally as frequently in both treatment groups. CONCLUSION: Apheresis with the Prosorba column is an efficacious treatment for RA in patients with active disease who have failed other treatments.

Identification of a new quantitative trait locus on chromosome 7 controlling disease severity of collagen-induced arthritis in rats.

Autoimmune diseases, such as rheumatoid arthritis, Crohn's disease, and multiple sclerosis, are regulated by multiple genes. Major histocompatibility complex (MHC) genes have the strongest effects, but non-MHC genes also contribute to disease susceptibility/severity. In this paper, we describe a new non-MHC quantitative trait locus, Cia8, on rat Chromosome (Chr) 7 that controls collagen-induced arthritis severity in F2 progeny of DA and F344 inbred rats, and present an updated localization of Cia4 on the same chromosome. We also describe the location of mouse and human genes, orthologous to the genes in the genomic intervals containing Cia4 and Cia8, and provide evidence that the segment of rat Chr 7 containing Cia4 and Cia8 is homologous to segments of mouse Chr 10 and 15 and human Chr 8, 12, and 19.