Association of morbid obesity with disability in early inflammatory polyarthritis: results from the Norfolk Arthritis Register.

OBJECTIVE: Obesity has been associated with disease outcomes in inflammatory arthritis. This study aimed to investigate cross-sectionally the relationship between body mass index (BMI) and functional disability in a large inception cohort of patients with early inflammatory polyarthritis (IP). METHODS: Patients age ≥16 years with ≥2 swollen joints for ≥4 weeks were recruited into the Norfolk Arthritis Register. At the initial assessment, clinical and demographic data were obtained, joints were examined, and height and weight were measured. Blood samples were taken to measure inflammatory markers and autoantibodies, and patients completed the Health Assessment Questionnaire (HAQ) to assess functional disability. Univariate and multivariate ordinal regression were used to examine the cross-sectional association between BMI and the HAQ. Multiple imputation using chained equations allowed inclusion of patients with missing variables. RESULTS: A total of 1,246 patients were studied (median age 57 years). Of those patients, 782 patients (63%) were female and 303 (25%) were obese (BMI ≥30 kg/m(2) ). Morbid obesity (BMI ≥35 kg/m(2) ) was significantly associated with worse functional disability in the univariate and multivariate analysis with missing data imputed, adjusting for age, sex, symptom duration, smoking status, disease activity, autoantibodies, comorbidities, and treatment (multivariate odds ratio 1.87, 95% confidence interval 1.14-3.07). CONCLUSION: Morbid obesity in patients with early IP is associated with worse HAQ scores. This should be taken into account in patient management and when interpreting the HAQ in clinical practice.

Risk of septic arthritis in patients with rheumatoid arthritis and the effect of anti-TNF therapy: results from the British Society for Rheumatology Biologics Register.

OBJECTIVES: To evaluate the risk of septic arthritis (SA) in patients with rheumatoid arthritis (RA) treated with anti-tumour necrosis factor (TNF) therapy. METHODS: Using data from the British Society for Rheumatology Biologics Register, a prospective observational study, the authors compared the risk of SA between 11 881 anti-TNF-treated and 3673 non-biological disease-modifying antirheumatic drug (nbDMARD)-treated patients. RESULTS: 199 patients had at least one episode of SA (anti-TNF: 179, nbDMARD: 20). Incidence rates were: anti-TNF 4.2/1000 patient years (pyrs) follow-up (95% CI 3.6 to 4.8), nbDMARD 1.8/1000 pyrs (95% CI 1.1 to 2.7). The adjusted HR for SA in the anti-TNF cohort was 2.3 (95% CI 1.2 to 4.4). The risk did not differ significantly between the three agents: adalimumab, etanercept and infliximab. The risk was highest in the early months of therapy. The patterns of reported organisms differed in the anti-TNF cohort. Prior joint replacement surgery was a risk factor for SA in all patients. The rate of postoperative joint infection (within 90 days of surgery) was 0.7%. This risk was not significantly influenced by anti-TNF therapy. CONCLUSIONS: Anti-TNF therapy use in RA is associated with a doubling in the risk of SA. Physicians and surgeons assessing the RA patient should be aware of this potentially life-threatening complication.

Parity, time since last live birth and long-term functional outcome: a study of women participating in the Norfolk Arthritis Register.

OBJECTIVE: To investigate the relationship between pre-symptom onset live births and functional outcome in women with inflammatory polyarthritis (IP). METHODS: 1872 women with no subsequent pregnancies were registered with the Norfolk Arthritis Register between 1990 and 2004 and followed-up for a median of 5 years. Functional disability over time was assessed by Health Assessment Questionnaire (HAQ). The number and calendar year of past live births were recorded. Differences in HAQ score over time by parity and time since last live birth (latency), adjusted for age and symptom duration, were examined using linear random effects models. The results were then adjusted for a number of potential confounders. RESULTS: 1553 women (83%) had ≥1 live births before symptom onset. The median latency was 26 years (IQR 16-35). Parous women had significantly lower HAQ scores over time than nulliparous women (-0.19, 95% CI -0.32 to -0.06). Increasing latency was associated with increasing HAQ score; the mean HAQ score of women with a latency of approximately 32 years was the same as for nulliparous women. This was independent of autoantibody status, socioeconomic status, smoking history and comorbidity. CONCLUSION: Parous women who develop IP have better functional outcome over time than nulliparous women who develop IP. The beneficial effect of parity diminishes with time.

Influence of anti-tumor necrosis factor therapy on cancer incidence in patients with rheumatoid arthritis who have had a prior malignancy: results from the British Society for Rheumatology Biologics Register.

OBJECTIVE: To explore the influence of anti-tumor necrosis factor (anti-TNF) therapy upon the incidence of cancer in patients with rheumatoid arthritis (RA) and prior malignancy. METHODS: Using data from the British Society for Rheumatology Biologics Register, a national prospective observational study established in 2001, we identified 293 patients with a prior malignancy from over 14,000 patients with RA. We compared rates of incident malignancy in 177 anti-TNF-treated patients and 117 patients with active RA treated with traditional disease-modifying antirheumatic drugs (DMARDs), all with prior malignancy. One patient switched therapy and contributed to both cohorts. RESULTS: The rates of incident malignancy were 25.3 events/1,000 person-years in the anti-TNF cohort and 38.3/1,000 person-years in the DMARD cohort, generating an age- and sex-adjusted incidence rate ratio of 0.58 (95% confidence interval 0.23-1.43) for the anti-TNF-treated cohort compared with the DMARD cohort. Of the patients with prior melanomas, 3 (18%) of 17 in the anti-TNF cohort developed an incident malignancy, compared with 0 of 10 in the DMARD cohort. CONCLUSION: The way in which UK rheumatologists are selecting patients with RA and prior malignancy to receive anti-TNF therapy is not leading to an increased risk of incident malignancy. Although reassuring, these results should not be interpreted as indicating that it is safe to treat all RA patients with prior malignancy with anti-TNF therapy.

Influence of anti-TNF therapy on mortality in patients with rheumatoid arthritis-associated interstitial lung disease: results from the British Society for Rheumatology Biologics Register.

BACKGROUND: Anti-tumour necrosis factor (anti-TNF) therapy has been associated with reports of rapid severe progression of rheumatoid arthritis-associated interstitial lung disease (RA-ILD). However, reports also exist of favourable responses to anti-TNF therapy in patients with ILD. The aim of this study was to examine the influence of anti-TNF therapy on mortality in patients with pre-existing RA-ILD. METHODS: Using data from the British Society for Rheumatology Biologics Register, a national prospective observational study, 367 patients with pre-existing RA-ILD were identified (299 treated with anti-TNF therapy and 68 treated with traditional disease-modifying antirheumatic drugs (DMARDs)). RESULTS: 70/299 patients (23%) in the anti-TNF cohort died after a median follow-up of 3.8 years compared with 14/68 (21%) in the DMARD cohort after a median follow-up of 2.1 years. The mortality was 68 deaths/1000 person years (pyrs) (95% CI 53 to 86) in the anti-TNF cohort and 92/1000 pyrs (95% CI 50 to 155) in the DMARD cohort, generating an age- and sex-adjusted mortality rate ratio (aMRR) of 1.26 (95% CI 0.69 to 2.31). After further adjustment for potential confounders, the aMRR fell to 0.81 (95% CI 0.38 to 1.73) for the anti-TNF cohort compared with the DMARD cohort. RA-ILD was the underlying cause of death in 15/70 (21%) and 1/14 (7%) patients in the anti-TNF and DMARD cohorts, respectively. CONCLUSION: The mortality in patients with RA-ILD is not increased following treatment with anti-TNF therapy compared with traditional DMARDs. The proportion of deaths attributable to RA-ILD is higher in patients treated with anti-TNF therapy, although reporting bias may exist.

Drug-specific risk of tuberculosis in patients with rheumatoid arthritis treated with anti-TNF therapy: results from the British Society for Rheumatology Biologics Register (BSRBR).

BACKGROUND: The risk of tuberculosis (TB) in patients with rheumatoid arthritis (RA) is thought to be increased following anti-tumour necrosis factor (anti-TNF) therapy, with a proposed differential risk between the anti-TNF drugs etanercept (ETA), infliximab (INF) and adalimumab (ADA). OBJECTIVE: To compare directly the risk between drugs, to explore time to event, site of infection and the role of ethnicity. METHODS: Data from the British Society for Rheumatology Biologics Register (BSRBR), a national prospective observational study, were used to compare TB rates in 10 712 anti-TNF treated patients (3913 ETA, 3295 INF, 3504 ADA) and 3232 patients with active RA treated with traditional disease-modifying antirheumatic drugs. RESULTS: To April 2008, 40 cases of TB were reported, all in the anti-TNF cohort. The rate of TB was higher for the monoclonal antibodies ADA (144 events/100,000 person-years) and INF (136/100,000 person-years) than for ETA (39/100,000 person-years). After adjustment, the incidence rate ratio compared with ETA-treated patients was 3.1 (95% CI 1.0 to 9.5) for INF and 4.2 (1.4 to 12.4) for ADA. The median time to event was lowest for INF (5.5 months) compared with ETA (13.4 months) and ADA (18.5 months). 13/40 cases occurred after stopping treatment. 25/40 (62%) cases were extrapulmonary, of which 11 were disseminated. Patients of non-white ethnicity had a sixfold increased risk of TB compared with white patients treated with anti-TNF therapy. CONCLUSION: The rate of TB in patients with RA treated with anti-TNF therapy was three- to fourfold higher in patients receiving INF and ADA than in those receiving ETA.

EULAR evidence-based recommendations for cardiovascular risk management in patients with rheumatoid arthritis and other forms of inflammatory arthritis.

OBJECTIVES: To develop evidence-based EULAR recommendations for cardiovascular (CV) risk management in patients with rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA). METHODS: A multidisciplinary expert committee was convened as a task force of the EULAR Standing Committee for Clinical Affairs (ESCCA), comprising 18 members including rheumatologists, cardiologists, internists and epidemiologists, representing nine European countries. Problem areas and related keywords for systematic literature research were identified. A systematic literature research was performed using MedLine, Embase and the Cochrane library through to May 2008. Based on this literature review and in accordance with the EULAR's "standardised operating procedures", the multidisciplinary steering committee formulated evidence-based and expert opinion-based recommendations for CV risk screening and management in patients with inflammatory arthritis. RESULTS: Annual CV risk assessment using national guidelines is recommended for all patients with RA and should be considered for all patients with AS and PsA. Any CV risk factors identified should be managed according to local guidelines. If no local guidelines are available, CV risk management should be carried out according to the SCORE function. In addition to appropriate CV risk management, aggressive suppression of the inflammatory process is recommended to further lower the CV risk. CONCLUSIONS: Ten recommendations were made for CV risk management in patients with RA, AS and PsA. The strength of the recommendations differed between RA on the one hand, and AS and PsA, on the other, as evidence for an increased CV risk is most compelling for RA.

Non-steroidal anti-inflammatory drug use does not appear to be associated with increased cardiovascular mortality in patients with inflammatory polyarthritis: results from a primary care based inception cohort of patients.

OBJECTIVES: There is controversy about the effects of non-steroidal anti-inflammatory drugs (NSAIDs) on cardiovascular disease (CVD) mortality. The aim of this study was to explore associations between NSAID use and mortality in patients with inflammatory polyarthritis (IP). SUBJECTS AND METHODS: A total of 923 patients with new onset (IP), recruited to the UK Norfolk Arthritis Register (NOAR) between 1990-1994, were followed up to the end of 2004. Current medication was recorded annually for the first 6 years and then every 2-3 years. Rheumatoid factor (RF) and C-reactive protein (CRP) were measured. Logistic regression was used to calculate all cause and CVD mortality odds ratios (OR) for NSAID use at baseline and during follow-up, adjusting for gender and time-varying covariates: RF, CRP, joint counts, smoking, steroid use, DMARD use and other medication use. RESULTS: By 2004 there were 203 deaths, 85 due to CVD. At baseline, NSAIDs were used by 66% of patients. In final multivariate models, baseline NSAID use was inversely associated with all cause mortality (adjusted OR 0.62, 95% CI 0.45 to 0.84) and CVD mortality (adjusted OR 0.54, 95% CI 0.34 to 0.86). Interval NSAID use had weaker mortality associations: all cause mortality (adjusted OR 0.72, 95% CI 0.52 to 1.00), CVD mortality (adjusted hazard ratio (HR) 0.66, 95% CI 0.40 to 1.08). CONCLUSION: No excess CVD or all cause mortality was observed in NSAID users in this cohort of patients with IP. This is at variance with the literature relating to NSAID use in the general population. It is unclear whether this represents unmeasured confounders influencing a doctor's decision to avoid NSAIDs in the treatment of IP.

Association of rheumatoid factor and anti-cyclic citrullinated peptide positivity, but not carriage of shared epitope or PTPN22 susceptibility variants, with anti-tumour necrosis factor response in rheumatoid arthritis.

OBJECTIVE: To determine whether rheumatoid factor (RF), anti-cyclic citrullinated peptide (CCP) antibodies, or carriage of shared epitope (SE) and PTPN22 genetic susceptibility variants predict response to therapy in patients with rheumatoid arthritis (RA) treated with anti-tumour necrosis factor (TNF) agents. METHODS: UK-wide multicentre collaborations were established to recruit a large cohort of patients treated with anti-TNF drugs for RA. Serum RF, anti-CCP antibody and SE status were determined using commercially available kits. PTPN22 R620W genotyping was performed by Sequenom MassArray. Linear regression analyses were performed to investigate the role of these four factors in predicting response to treatment by 6 months, defined as the absolute change in 28-joint Disease Activity Score (DAS28). RESULTS: Of the 642 patients analysed, 46% received infliximab, 43% etanercept and 11% adalimumab. In all, 89% and 82% of patients were RF and anti-CCP positive, respectively. Patients that were RF negative had a 0.48 (95% CI 0.08 to 0.87) greater mean improvement in DAS28 compared to patients that were RF positive. A better response was also seen among patients that were anti-CCP negative. No association was demonstrated between drug response and SE or PTPN22 620W carriage. CONCLUSION: The presence of RF or anti-CCP antibodies was associated with a reduced response to anti-TNF drugs. However, these antibodies only account for a small proportion of the variance in treatment response. It is likely that genetic factors will contribute to treatment response, but these do not include the well established RA susceptibility loci, SE and PTPN22.

Rates of new-onset psoriasis in patients with rheumatoid arthritis receiving anti-tumour necrosis factor alpha therapy: results from the British Society for Rheumatology Biologics Register.

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.

European biologicals registers: methodology, selected results and perspectives.

With the licensing of the first tumour necrosis factor (TNF)alpha inhibitors, independent academia-initiated but industry-sponsored drug registers were set up by the national rheumatology societies in several European countries in order to monitor the long-term safety and effectiveness of this new generation of drugs. Even though different in some respects of study design and monitoring, the registers share a number of common features: they include all licensed biological agents, they observe the patients for a defined period of time or indefinitely irrespective of the drug given and they use comparator cohorts or national registers in order to put the results into perspective. The registers have been collaborating closely since inception. Three of them (the British, Swedish and German registers) have agreed on a standardised reporting system of adverse events which ensures a high and uniform quality of data submitted to the companies, who subsequently report to the drug regulatory authorities, enabling regulatory requirements on safety surveillance to be fulfilled. In the present work, major results on drug safety with regard to infections, malignancies, cardiovascular events, pregnancy outcomes and deaths are summarised. With an increasing number of new drugs and multiple exposures of individual patients the assignment of events to specific treatments will become exceedingly difficult. This and other methodological challenges and the approaches to cope with them are discussed. A growing dialogue between drug regulatory authorities, academic medicine and companies in order to make best use of the potentials of academia-driven drug registers as new tools for pharmacovigilance with currently described rheumatology registers as prototypes is anticipated.

Effects of switching between anti-TNF therapies on HAQ response in patients who do not respond to their first anti-TNF drug.

OBJECTIVES: Small studies have shown an improvement in disease activity in patients with RA who have switched between anti-TNF therapies for reasons of inefficacy. However, it is not clear whether switching improves longer term outcomes, such as disability. This analysis compares changes in HAQ scores 1 yr following lack of response to a first anti-TNF based on subsequent treatment during that year. METHODS: Analysis was limited to RA patients with inefficacy to a first anti-TNF based on (i) clinician opinion and/or (ii) disease activity score in 28 joints and had an HAQ measured at time of non-response and 12 months later. Patients were classified into three groups based on treatment during the next 12 months: (i) continued anti-TNF despite non-response; (ii) stopped anti-TNF with no further biologics; and (iii) switched to a second anti-TNF. Mean improvement in HAQ was compared among the groups using multivariable linear regression models. RESULTS: As of July 2006, 868 patients met the inclusion for this analysis. Four hundred and seventy-nine patients stopped anti-TNF of whom 331 switched to a second anti-TNF. Three hundred and eighty-nine continued treatment. Patients who continued and those who switched had improvements in HAQ over the 12 months, unlike patients who discontinued all biologic therapy. The best improvement was seen in those who switched [adjusted mean improvement in HAQ 0.15 (95% CI 0.26, 0.05)]. CONCLUSION: There is a significant improvement in HAQ in patients who switch to a second anti-TNF, providing an effective next choice of therapy for some patients who fail to respond to their first anti-TNF.

Reduction in the incidence of myocardial infarction in patients with rheumatoid arthritis who respond to anti-tumor necrosis factor alpha therapy: results from the British Society for Rheumatology Biologics Register.

OBJECTIVE: Rheumatoid arthritis (RA) is associated with an increased risk of coronary artery disease, possibly acting via shared mechanisms of inflammation. This study was undertaken to test the hypothesis that the powerful antiinflammatory effect of anti-tumor necrosis alpha (anti-TNFalpha) therapy might lead to a reduction in the incidence of myocardial infarction (MI) in patients with RA. METHODS: Using data from the British Society for Rheumatology Biologics Register, a national prospective observational study, we compared MI rates in 8,670 patients with RA treated with anti-TNFalpha and 2,170 patients with active RA treated with traditional disease-modifying antirheumatic drugs (DMARDs). RESULTS: Through July 2006, 63 MIs occurred in the anti-TNFalpha cohort during 13,233 person-years of followup and 17 MIs occurred in the DMARD cohort during 2,893 person-years of followup, equivalent to a rate of 4.8 events per 1,000 person-years and 5.9 events per 1,000 person-years, respectively. After adjustment for baseline risk factors, there was no reduction in the rate of MI in the anti-TNFalpha cohort compared with the DMARD cohort (incidence rate ratio 1.44 [95% confidence interval 0.56-3.67]). In an analysis of anti-TNFalpha-treated patients who responded to the treatment within 6 months versus those who did not, MI rates were found to be 3.5 events per 1,000 person-years in responders and 9.4 events per 1,000 person-years in nonresponders. The adjusted incidence rate ratio (95% confidence interval) for responders compared with nonresponders was 0.36 (0.19-0.69). CONCLUSION: These results indicate that RA patients treated with anti-TNFalpha do not have a lower incidence of MI compared with RA patients treated with traditional DMARDs. However, the risk of MI is markedly reduced in those who respond to anti-TNFalpha therapy by 6 months compared with nonresponders. This finding supports the notion that inflammation plays a pivotal role in MI.

Serious infection following anti-tumor necrosis factor alpha therapy in patients with rheumatoid arthritis: lessons from interpreting data from observational studies.

OBJECTIVE: In a recent observational study, we found that the risk of serious infection following anti-tumor necrosis factor alpha (anti-TNFalpha) therapy in patients with rheumatoid arthritis (RA) was not importantly increased compared with the background risk in routinely treated RA patients with similar disease severity. Observational data sets are, however, subject to a number of important biases related to selection factors for the timing of starting and stopping therapy. Infection risk is also likely to vary with duration of therapy. This study was undertaken to examine the influences of these biases and of the method of analysis on the risk of infection. METHODS: We compared the risk of serious infection in 8,659 patients treated with anti-TNFalpha with that in 2,170 patients treated with traditional disease-modifying antirheumatic drugs (DMARDs) recruited to the British Society for Rheumatology Biologics Register. We applied a number of statistical models in which we varied the length of the followup period by using different definitions of the date of discontinuation of treatment and different lag periods of risk following drug cessation. RESULTS: When the at-risk period was defined as "receiving treatment", the adjusted incidence rate ratio comparing patients receiving anti-TNFalpha therapy with patients receiving DMARD therapy was 1.22 (95% confidence interval [95% CI] 0.88-1.69). Limiting followup to the first 90 days, however, revealed an adjusted incidence rate ratio of 4.6 (95% CI 1.8-11.9). Rates of infection were increased in the 90 days immediately following drug discontinuation and beyond, explained by selection factors for drug discontinuation. CONCLUSION: These findings show that overall, the way in which UK rheumatologists select patients for starting and discontinuing anti-TNFalpha therapy explains our previous finding of no increase in risk. However, there may be important increases in true risk, notably early in the course of treatment, that would become more evident depending on the definition of at-risk period.

What effects might anti-TNFalpha treatment be expected to have on cardiovascular morbidity and mortality in rheumatoid arthritis? A review of the role of TNFalpha in cardiovascular pathophysiology.

Patients with rheumatoid arthritis (RA) have an increased burden of atherosclerotic cardiovascular disease which cannot be explained by an increased prevalence of traditional cardiovascular risk factors alone. Atherosclerosis is now being viewed as an inflammatory condition and the cumulative inflammation experienced in RA may contribute to accelerated atherosclerosis. It has been hypothesised that treatment with anti-tumour necrosis factor (TNF) alpha in RA may reduce both intra-articular inflammation and the inflammation associated with atherosclerosis. Thus, TNFalpha blockade may reduce the cardiovascular morbidity and mortality associated with RA. This review examines the pathophysiological role of TNFalpha in atherosclerosis and the evidence to date that anti-TNFalpha treatment modifies this process in RA.

Rates of serious infection, including site-specific and bacterial intracellular infection, in rheumatoid arthritis patients receiving anti-tumor necrosis factor therapy: results from the British Society for Rheumatology Biologics Register.

OBJECTIVE: To determine whether the rate of serious infection is higher in anti-tumor necrosis factor (anti-TNF)-treated rheumatoid arthritis (RA) patients compared with RA patients treated with traditional disease-modifying antirheumatic drugs (DMARDs). METHODS: This was a national prospective observational study of 7,664 anti-TNF-treated and 1,354 DMARD-treated patients with severe RA from the British Society for Rheumatology Biologics Register. All serious infections, stratified by site and organism, were included in the analysis. RESULTS: Between December 2001 and September 2005, there were 525 serious infections in the anti-TNF-treated cohort and 56 in the comparison cohort (9,868 and 1,352 person-years of followup, respectively). The incidence rate ratio (IRR), adjusted for baseline risk, for the anti-TNF-treated cohort compared with the comparison cohort was 1.03 (95% confidence interval 0.68-1.57). However, the frequency of serious skin and soft tissue infections was increased in anti-TNF-treated patients, with an adjusted IRR of 4.28 (95% confidence interval 1.06-17.17). There was no difference in infection risk between the 3 main anti-TNF drugs. Nineteen serious bacterial intracellular infections occurred, exclusively in patients in the anti-TNF-treated cohort. CONCLUSION: In patients with active RA, anti-TNF therapy was not associated with increased risk of overall serious infection compared with DMARD treatment, after adjustment for baseline risk. In contrast, the rate of serious skin and soft tissue infections was increased, suggesting an important physiologic role of TNF in host defense in the skin and soft tissues beyond that in other tissues.

Predictors of response to anti-TNF-alpha therapy among patients with rheumatoid arthritis: results from the British Society for Rheumatology Biologics Register.

BACKGROUND: Anti-tumour necrosis factor-alpha (TNF-alpha) therapies represent an important advancement in therapy for rheumatoid arthritis (RA). However, there remains a proportion of patients who do not improve despite therapy. These drugs are expensive and have the potential of serious toxicity. Therefore, it would be ideal to predict the patients who will respond, so that the use of these drugs can be targetted. OBJECTIVE: To identify the clinical factors present at the start of anti-TNF-alpha therapy that are associated with response at 6 months in patients with RA. METHODS: The British Society for Rheumatology (BSR) Biologics Register collects detailed data on all patients with a rheumatic disease receiving biologic therapy in the UK. We studied all patients with RA who had started etanercept (ETA) or infliximab (INF) and had achieved a minimum 6 months follow-up by 1 October, 2004. The disease status at the baseline and at 6 months was assessed using the Disease Activity Score (DAS28). The response was classified according to the European League against Rheumatism (EULAR) improvement criteria. The effect of baseline characteristics on response was studied using multivariate ordinal logistic regression. RESULTS: 2879 patients were included in this analysis (1267 ETA, 1612 INF). At the start of therapy, the mean age was 55 yrs, disease duration 14 yrs, baseline DAS28 6.7 and health assessment questionnaire (HAQ) 2.1. In all, 28% of ETA and 86% of INF patients were receiving methotrexate. After 6 months, 18% had a good EULAR response, of whom 9% were considered to be in remission and 50% had a moderate response. There was no overall difference in response rate between the two anti-TNF-alpha therapies. A higher baseline HAQ score correlated with a lower response rate while a better response was associated with the current use of NSAIDs and the use of methotrexate (MTX), although the latter only reached statistical significance with ETA [OR 1.82 (95% CI 1.38-2.40)]. There was a lower response rate among current smokers, particularly in patients receiving INF [OR 0.77 (95% CI 0.60-0.99)]. Age, disease duration, rheumatoid factor and the previous number of disease-modifying antirheumatic drugs (DMARDs) did not predict response to either drug. However, females were less likely to achieve remission. CONCLUSIONS: These data support an improved outcome among patients receiving MTX in combination with anti-TNF-alpha therapies. However, the most disabled patients were less likely to respond, despite concurrent MTX. The benefits of NSAIDs may reflect the relative absence of comorbidities in patients who can tolerate these drugs or the continuing presence of reversible inflammatory symptoms. The association of smoking and poor outcome with INF is a novel finding and may reflect alterations in pharmacokinetics. The inability of other baseline disease characteristics to predict the outcome suggests that other factors, including potential genetic differences in drug metabolism, may be influencing the response to anti-TNF-alpha therapies.