Survival in rheumatoid arthritis: a population-based analysis of trends over 40 years

OBJECTIVE: To evaluate trends in and risk factors for mortality among patients with rheumatoid arthritis (RA) over a 40-year period. METHODS: A population-based inception cohort was assembled from among all Rochester, Minnesota residents ages > or =18 years who were first diagnosed with RA (fulfilling the 1987 American College of Rheumatology criteria for RA) between January 1, 1955 and December 31, 1994. Patients were followed up longitudinally through their entire medical records (including all inpatient and outpatient care by any provider) until death or migration from the county. Survival was described using the Kaplan-Meier method. Observed and expected survival were compared using the log-rank test, and standardized mortality ratios (SMRs) with expected survival were based on the sex and age of the study population and death rates from the Minnesota life tables. Cox proportional hazards models were used to estimate the influence of extraarticular manifestations and comorbidities, controlling for age, sex, body mass index (BMI), smoking, and rheumatoid factor positivity. RESULTS: Survival in this RA cohort was significantly lower than that expected in the population (P < 0.001) over the entire time period. Patients with RA were at significantly higher risk of death, with an SMR of 1.27 (95% confidence interval 1.13-1.41). Excess mortality among women was more pronounced than among men, with SMRs of 1.41 and 1.08, respectively. Presence of > or =1 extraarticular manifestation was the strongest predictor of mortality after adjusting for age, sex, BMI, smoking, and rheumatoid factor positivity. CONCLUSION: Survival in RA patients is significantly lower than expected. The strongest predictors of survival appear to be those related to RA disease complications, specifically, extraarticular manifestations of the disease and comorbidities. More attention should be paid to mortality as an outcome measure in RA.     

Cardiovascular death in rheumatoid arthritis: a population-based study

OBJECTIVE: To determine whether systemic inflammation confers any additional risk for cardiovascular death among patients with rheumatoid arthritis (RA), after adjusting for traditional cardiovascular risk factors and comorbidities. METHODS: Using the population-based data resources of the Rochester Epidemiology Project, we assembled an incidence cohort of all Rochester, Minnesota residents ages >or=18 years who first fulfilled the American College of Rheumatology 1987 criteria for RA between January 1, 1955 and January 1, 1995. All subjects were followed up longitudinally through their complete (inpatient, outpatient) medical records, beginning at age 18 years and continuing until death, migration, or January 1, 2001. Detailed information on the occurrence of various cardiovascular risk factors (personal history of coronary heart disease [CHD], congestive heart failure, smoking, hypertension, dyslipidemia, body mass index [BMI], diabetes mellitus, menopausal status) as well as indicators of systemic inflammation and RA disease severity (rheumatoid factor [RF] seropositivity, erythrocyte sedimentation rate [ESR], joint swelling, radiographic changes, RA nodules, RA complications, RA treatments, disease duration) and comorbidities were collected on all subjects. Causes of death were ascertained from death certificates and medical records. Cox regression models were used to estimate the independent predictors of cardiovascular death. RESULTS: This inception cohort comprised a total of 603 RA patients whose mean age was 58 years, of whom 73% were women. During a mean followup of 15 years, 354 patients died and cardiovascular disease was the primary cause of death in 176 patients. Personal history of CHD, smoking, hypertension, low BMI, and diabetes mellitus, as well as comorbidities, including peripheral vascular disease, cerebrovascular disease, chronic pulmonary disease, dementia, ulcers, malignancies, renal disease, liver disease, and history of alcoholism, were all significant risk factors for cardiovascular death (P < 0.01 for each). Multivariable Cox regression analyses, controlled for cardiovascular risk factors and comorbidities, revealed that the risk of cardiovascular death was significantly higher among RA patients with at least 3 ESR values of >or=60 mm/hour (hazard ratio [HR] 2.03, 95% confidence interval [95% CI] 1.45-2.83), RA vasculitis (HR 2.41, 95% CI 1.00-5.81), and RA lung disease (HR 2.32, 95% CI 1.11-4.84). CONCLUSION: These results indicate that markers of systemic inflammation confer a statistically significant additional risk for cardiovascular death among patients with RA, even after controlling for traditional cardiovascular risk factors and comorbidities.     

Occurrence of extraarticular disease manifestations is associated with excess mortality in a community based cohort of patients with rheumatoid arthritis

OBJECTIVE: To investigate the occurrence of extraarticular manifestations (ExRA) in a well defined community based cohort of patients with rheumatoid arthritis (RA), and to examine their effect on mortality. METHODS: Using the resources of the Rochester Epidemiology Project, a retrospective medical record review was conducted of a cohort of 424 cases of RA in Olmsted County, MN, USA, diagnosed during the period 1955-1985. These cases had been classified using the American College of Rheumatology 1987 criteria for RA. Patients were followed 1955-1998 (median followup 14.8 yrs; range 0.2-42.8 yrs), and incident ExRA manifestations were recorded according to predefined criteria. Data on comorbidities were extracted using the definitions of the Charlson comorbidity index. Survival was compared to the general population using Kaplan-Meier estimates. RESULTS: ExRA occurred in 169 patients, corresponding to an incidence rate of 3.67/100 person-yrs. Compared to the general population, survival among patients with RA was decreased. Survival among patients with ExRA was markedly decreased compared to the general population and to patients without ExRA (p < 0.001). A particularly poor prognosis was noted in a subgroup of 63 patients (incidence rate 1.04/100 person-yrs) who fulfilled predefined criteria for severe ExRA (i.e., vasculitis, pericarditis, pleuritis, and/or Felty's syndrome). For RA patients who did not fulfill these criteria, there was no significant increase of mortality (p = 0.09). In a multivariate model of mortality, including age, sex, and the presence of known comorbidities, the presence of one or more of these ExRA was the strongest predictor of mortality. CONCLUSION: In this first community based study of extraarticular manifestations in RA, virtually all the excess mortality occurred in a subgroup of patients with severe extraarticular disease, suggesting that extraarticular disease is the major predictor of mortality in patients with RA.     

Cardiovascular disease in rheumatoid arthritis: medications and risk factors in China

This study aims to assess the risk factors of cardiovascular disease (CVD) and to determine the association of traditional and biologic disease-modifying anti-rheumatic drugs (DMARDs) with risk for CVD in Chinese rheumatoid arthritis (RA) patients. A cross-sectional cohort of 2013 RA patients from 21 hospitals around China was established. Medical history of CVD was documented. The patients’ social background, clinical manifestations, comorbidities, and medications were also collected. Of the 2013 patients, 256 had CVD with an incidence of 12.7%. Compared with non-CVD controls, RA patients with CVD had a significantly advanced age, long-standing median disease duration, more often male and more deformity joints. Patients with CVD also had higher rates of smoking, rheumatoid nodules, interstitial lung disease, and anemia. The prevalence of comorbidities, including hypothyroidism, diabetes mellitus (DM), hypertension, and hyperlipidemia, was also significant higher in the CVD group. In contrast, patients treated with methotrexate, hydroxychloroquine (HCQ), and TNF blockers had lower incidence of CVD. The multivariate analysis showed that the use of HCQ was a protective factor of CVD, while hypertension, hyperlipidemia, and interstitial lung disease were independent risk factors of CVD. Our study shows that the independent risk factors of CVD include hypertension, hyperlipidemia, and interstitial lung disease. HCQ reduces the risk of CVD in patients with RA.     

Incidence of noncardiac vascular disease in rheumatoid arthritis and relationship to extraarticular disease manifestations

OBJECTIVE: To investigate the incidence of noncardiac vascular disease in patients with rheumatoid arthritis (RA) and its relationship to systemic extraarticular disease in a community-based cohort. METHODS: A retrospective medical record review of 609 patients with incident RA diagnosed during 1955-1994 was carried out in Olmsted County, Minnesota. Patients were followed up from 1955 to 2000 (median followup 11.8 years). Incident noncardiac vascular disease and severe extraarticular RA manifestations (including pericarditis, pleuritis, and vasculitis) were recorded according to predefined criteria, and incidence rates were estimated. Using Cox proportional hazards models, the risk (hazard ratio [HR]) of developing vascular events was assessed in patients with and without severe extraarticular RA. RESULTS: Cerebrovascular and peripheral arterial events occurred in 139 patients (22.8%). The 30-year cumulative incidence rates of peripheral arterial events, cerebrovascular events, and venous thromboembolic events were estimated to be 19.6%, 21.6%, and 7.2%, respectively. The presence of severe extraarticular RA manifestations was found to be associated with all subgroups of noncardiac vascular disease except cerebrovascular disease alone (HR 2.3, 95% confidence interval [95% CI] 1.2-4.3 for peripheral arterial events; HR 3.7, 95% CI 1.3-10.3 for venous thromboembolic events; HR 1.5, 95% CI 0.7-3.2 for cerebrovascular events) after adjusting for age, sex, body mass index, smoking, and rheumatoid factor status. CONCLUSION: This is the first study to assess the incidence of noncardiac vascular disease in RA. Severe extraarticular RA was associated with all forms of noncardiac vascular disease except cerebrovascular disease alone. Similar to cardiac disease, the excess risk of noncardiac vascular disease in RA is likely to be related, in part, to the systemic inflammation associated with the extraarticular manifestations of RA.     

Frequency of infection in patients with rheumatoid arthritis compared with controls: a population-based study

OBJECTIVE: A high frequency of infections complicating rheumatoid arthritis (RA) has been described in reports of case series. This retrospective longitudinal cohort study was undertaken to compare the frequency of infections in a population-based incidence cohort of RA patients with that in a group of individuals without RA from the same population. METHODS: RA patients included all members of an incidence cohort of Rochester, Minnesota residents ages >or=18 years who were first diagnosed as having RA between 1955 and 1994. One age- and sex-matched subject without RA was selected for each patient with RA. Study subjects were followed up by review of their entire medical record until death, migration from the area, or study end (January 1, 2000), and details of all documented infections, along with information on potential risk factors for infection, were recorded. Hazard ratios for infections were estimated using stratified Andersen-Gill proportional hazards models, with adjustment for potential confounders. RESULTS: The 609 RA patients and 609 non-RA study subjects (mean age 58.0 years; 73.1% female) were followed up for a mean of 12.7 years and 15.0 years, respectively, reflecting higher mortality among the group with RA. Hazards ratios for objectively confirmed infections, infections requiring hospitalization, and any documented infection in patients with RA were 1.70 (95% confidence interval [95% CI] 1.42-2.03), 1.83 (95% CI 1.52-2.21), and 1.45 (95% CI 1.29-1.64), respectively, after adjustment for age, sex, smoking status, leukopenia, corticosteroid use, and diabetes mellitus. Sites of infection with the highest risk ratios were bone, joints, skin, soft tissues, and the respiratory tract. CONCLUSION: In this study, patients with RA were at increased risk of developing infections compared with non-RA subjects. This may be due to immunomodulatory effects of RA, or to agents with immunosuppressive effects used in its treatment.     

Cardiovascular death in rheumatoid arthritis: A population‐based study

Objective

To determine whether systemic inflammation confers any additional risk for cardiovascular death among patients with rheumatoid arthritis (RA), after adjusting for traditional cardiovascular risk factors and comorbidities.

Methods

Using the population‐based data resources of the Rochester Epidemiology Project, we assembled an incidence cohort of all Rochester, Minnesota residents ages ≥18 years who first fulfilled the American College of Rheumatology 1987 criteria for RA between January 1, 1955 and January 1, 1995. All subjects were followed up longitudinally through their complete (inpatient, outpatient) medical records, beginning at age 18 years and continuing until death, migration, or January 1, 2001. Detailed information on the occurrence of various cardiovascular risk factors (personal history of coronary heart disease [CHD], congestive heart failure, smoking, hypertension, dyslipidemia, body mass index [BMI], diabetes mellitus, menopausal status) as well as indicators of systemic inflammation and RA disease severity (rheumatoid factor [RF] seropositivity, erythrocyte sedimentation rate [ESR], joint swelling, radiographic changes, RA nodules, RA complications, RA treatments, disease duration) and comorbidities were collected on all subjects. Causes of death were ascertained from death certificates and medical records. Cox regression models were used to estimate the independent predictors of cardiovascular death.

Results

This inception cohort comprised a total of 603 RA patients whose mean age was 58 years, of whom 73% were women. During a mean followup of 15 years, 354 patients died and cardiovascular disease was the primary cause of death in 176 patients. Personal history of CHD, smoking, hypertension, low BMI, and diabetes mellitus, as well as comorbidities, including peripheral vascular disease, cerebrovascular disease, chronic pulmonary disease, dementia, ulcers, malignancies, renal disease, liver disease, and history of alcoholism, were all significant risk factors for cardiovascular death (P < 0.01 for each). Multivariable Cox regression analyses, controlled for cardiovascular risk factors and comorbidities, revealed that the risk of cardiovascular death was significantly higher among RA patients with at least 3 ESR values of ≥60 mm/hour (hazard ratio [HR] 2.03, 95% confidence interval [95% CI] 1.45–2.83), RA vasculitis (HR 2.41, 95% CI 1.00–5.81), and RA lung disease (HR 2.32, 95% CI 1.11–4.84).

Conclusion

These results indicate that markers of systemic inflammation confer a statistically significant additional risk for cardiovascular death among patients with RA, even after controlling for traditional cardiovascular risk factors and comorbidities.

     

Declining use of orthopedic surgery in patients with rheumatoid arthritis? Results of a long-term,population-based assessment

OBJECTIVE: To describe the use of orthopedic surgery, including joint replacement surgery, in a well-defined, population-based cohort of patients with rheumatoid arthritis (RA) and to identify characteristics that predict such use. METHODS: A retrospective medical record review was performed of cases of RA incident in Rochester, Minnesota, during the years 1955-1995. All joint surgeries were recorded. RESULTS: Of the total 609 RA incident cases, 242 patients underwent 1 or more (maximum of 20/patient) surgical procedures involving joints during their followup. Overall, this RA cohort had 7.4 surgeries per 100 person-years of followup; the cumulative incidence for joint surgery for RA-related joint disease at 30 years was 33.7% +/- SEM 3.8%. The risk of having a disease-related joint surgery for RA is increased in patients who are women, younger, positive for rheumatoid factor, and have rheumatoid nodules. When adjusted for duration of followup, patients with RA diagnosed after 1985 were significantly less likely to have undergone joint surgery for RA (P < 0.001). Survival of patients who underwent total joint arthroplasty was similar to those who did not. CONCLUSION: Reconstructive surgeries are common in RA, although patients diagnosed after 1985 are less likely to require joint surgery. These findings may reflect trends in medical disease management and have importance for health care resource utilization planning.     

Use of nonbiologic disease-modifying antirheumatic drugs and risk of infection in patients with rheumatoid arthritis

OBJECTIVE: Rheumatoid arthritis (RA) is associated with increased frequency of and mortality from infections, which may be related to host factors, RA itself, inflammation, or medication side effects. This study was undertaken to determine the effect of nonbiologic disease-modifying antirheumatic drugs (DMARDs) on infection risk in RA. METHODS: We performed a retrospective, longitudinal study of a population-based RA cohort in British Columbia, Canada, followed from January 1996 to March 2003 using administrative data. We evaluated mild infections (requiring a physician visit or antibiotics) and serious infections (requiring or complicating hospitalization). Adjusted risk of mild and serious infections associated with DMARD exposure was estimated using generalized estimating equation extension of multivariate Poisson regression models, after adjusting for baseline covariates (age, sex, RA duration, socioeconomic status) and time-dependent covariates (corticosteroids, comorbidity, prior infections). RESULTS: A total of 27,710 individuals with RA provided 162,710 person-years of followup. Of these, 25,608 (92%) had at least 1 mild infection and 4,941 (18%) had at least 1 serious infection. Use of DMARDs without corticosteroids was associated with a small decrease in mild infection risk of statistical significance but unclear clinical significance (adjusted rate ratio [RR] 0.90, 95% confidence interval [95% CI] 0.88-0.93 relative to no corticosteroid or DMARD use). Use of DMARDs without corticosteroids was not associated with increased serious infection risk (adjusted RR 0.92, 95% CI 0.85-1.0). Use of corticosteroids increased the risk of mild and serious infections. CONCLUSION: Our results indicate that use of nonbiologic DMARDs, including methotrexate, does not increase the risk of infection in RA, whereas use of corticosteroids does. This has important implications for counseling individuals with RA concerning risks and benefits of DMARDs.     

Survival in rheumatoid arthritis: A population‐based analysis of trends over 40 years

Objective

To evaluate trends in and risk factors for mortality among patients with rheumatoid arthritis (RA) over a 40‐year period.

Methods

A population‐based inception cohort was assembled from among all Rochester, Minnesota residents ages ≥18 years who were first diagnosed with RA (fulfilling the 1987 American College of Rheumatology criteria for RA) between January 1, 1955 and December 31, 1994. Patients were followed up longitudinally through their entire medical records (including all inpatient and outpatient care by any provider) until death or migration from the county. Survival was described using the Kaplan‐Meier method. Observed and expected survival were compared using the log‐rank test, and standardized mortality ratios (SMRs) with expected survival were based on the sex and age of the study population and death rates from the Minnesota life tables. Cox proportional hazards models were used to estimate the influence of extraarticular manifestations and comorbidities, controlling for age, sex, body mass index (BMI), smoking, and rheumatoid factor positivity.

Results

Survival in this RA cohort was significantly lower than that expected in the population (P < 0.001) over the entire time period. Patients with RA were at significantly higher risk of death, with an SMR of 1.27 (95% confidence interval 1.13–1.41). Excess mortality among women was more pronounced than among men, with SMRs of 1.41 and 1.08, respectively. Presence of ≥1 extraarticular manifestation was the strongest predictor of mortality after adjusting for age, sex, BMI, smoking, and rheumatoid factor positivity.

Conclusion

Survival in RA patients is significantly lower than expected. The strongest predictors of survival appear to be those related to RA disease complications, specifically, extraarticular manifestations of the disease and comorbidities. More attention should be paid to mortality as an outcome measure in RA.

     

Risk factors for severe infections in patients with rheumatoid arthritis treated with rituximab in the autoimmunity and rituximab registry

Objective

The risk of severe infection is a crucial factor in the assessment of the short‐term risk:benefit ratio of biologic drugs in rheumatoid arthritis (RA). There is no increase in severe infections in RA patients treated with rituximab (RTX) in controlled trials, but this has not yet been assessed in daily practice. We undertook this study to investigate the occurrence of and risk factors for severe infections in off‐trial patients using data from the AutoImmunity and Rituximab (AIR) registry.

Methods

The AIR registry was set up by the French Society of Rheumatology. The charts of patients with severe infections were reviewed.

Results

Of the enrolled patients, 1,303 had at least 1 followup visit at 3 months or later, with a mean ± SD followup period of 1.2 ± 0.8 years (1,629 patient‐years). Eighty‐two severe infections occurred in 78 patients (5.0 severe infections per 100 patient‐years), half of them in the 3 months following the last RTX infusion. Multivariate analysis showed that chronic lung disease and/or cardiac insufficiency (odds ratio 3.0 [95% confidence interval 1.3–7.3], P = 0.01), extraarticular involvement (odds ratio 2.9 [95% confidence interval 1.3–6.7], P = 0.009), and low IgG level (<6 gm/liter) before initiation of RTX treatment (odds ratio 4.9 [95% confidence interval 1.6–15.2], P = 0.005) were significantly associated with increased risk of a severe infection.

Conclusion

The rate of severe infections in current practice is similar to that reported in clinical trials. The risk factors for severe infections include chronic lung and/or cardiac disease, extraarticular involvement, and low IgG before RTX treatment. This suggests that serum IgG should be checked and the risk:benefit ratio of RTX discussed for patients found to have low levels of IgG.

     

Prognostic factors for joint destruction in rheumatoid arthritis: a prospective longitudinal study of 318 patients

OBJECTIVE: To quantify articular damage and to investigate prognostic factors for joint damage progression in rheumatoid arthritis (RA). METHODS: RA patients satisfying the 1987 American College of Rheumatology criteria and with disease duration under 5 years were sampled from the EURIDISS longitudinal cohort study in Norway, The Netherlands, and France. Hand radiographs were assessed at baseline and at 2 to 3 year followup using Sharp score modified by van der Heijde. Assessment of erosion and joint space narrowing, performed in sequential order by a single reader blinded to patients' characteristics, had high intraobserver reproducibility (intraclass correlation coefficient 0.98-0.99). Baseline prognostic factors were analyzed in a multivariate linear regression model. RESULTS: A total of 318 patients with RA aged 52.4 years (70.4% were female) and with a mean 2 years' disease duration at baseline were followed over 30 months. Median (quartiles) baseline and followup modified Sharp scores were 3 (0-11) and 9 (1-27), respectively, with 35.8% and then 22.3% of patients with no radiological damage. Controlling for age, sex, and country, the final joint damage was predicted by baseline modified Sharp score, rheumatoid factor positivity, time from disease diagnosis, patient global health assessment, and erythrocyte sedimentation rate, and by followup duration, explaining 76.8% of the outcome variance. CONCLUSION: This multinational study confirmed the prognostic role in RA of a set of features previously identified in smaller cohorts. It indicates which disease characteristics should be focused on in the early years of RA to identify patients at higher risk of developing severe disease and who are candidates for aggressive therapy.     

Incidence and risk factors of prosthetic joint infection after total hip or knee replacement in patients with rheumatoid arthritis

Objective

Prosthetic joint infection is one of the most dreaded complications after total joint arthroplasty, a common procedure in patients with rheumatoid arthritis (RA). We conducted a study to evaluate potential risk factors of prosthetic joint infection and to clarify if RA is an independent predictor of this complication.

Methods

This study included all patients with RA who underwent total hip or knee replacement at the Mayo Clinic Rochester between January 1996 and June 2004. The association of potential risk factors with prosthetic joint infection was examined using Cox models. A matched cohort of patients with osteoarthritis (OA) was assembled to determine whether RA is an independent risk factor for prosthetic joint infection.

Results

We identified 462 patients with RA who underwent a total of 657 hip or knee replacements. Overall, 23 (3.7%) joint arthroplasties were complicated by an infection during a mean ± SD followup of 4.3 ± 2.4 years. Revision arthroplasty (hazard ratio [HR] 2.99, 95% confidence interval [95% CI] 1.02–8.75) and a previous prosthetic joint infection of the replaced joint (HR 5.49, 95% CI 1.87–16.14) were significant predictors of postoperative prosthetic joint infection. Comparison of RA patients with a matched cohort of OA patients identified an increased risk of prosthetic joint infections (HR 4.08, 95% CI 1.35–12.33) in patients with RA.

Conclusion

Patients with RA who undergo total hip or knee replacement are at increased risk of prosthetic joint infection, which is further increased in the setting of revision arthroplasty and a previous prosthetic joint infection. These findings highlight the importance of perioperative prophylactic measures and vigilance during the postoperative period.     

The influence of age at symptom onset and length of followup on mortality in patients with recent-onset inflammatory polyarthritis

OBJECTIVE: To investigate the influence of age at symptom onset and length of followup on mortality in patients with recent-onset inflammatory polyarthritis (IP), and to examine predictors of mortality in relation to disease duration. METHODS: From 1990 to 1994, patients with recent-onset IP were registered with the Norfolk Arthritis Register (NOAR) and followed up prospectively. Standardized mortality ratios (SMRs) were calculated for all-cause and cardiovascular disease (CVD) mortality and for those who were younger than age 55 years at disease onset and for the first 5 and 10 years of followup. Cox proportional hazards models were developed to assess predictors of early and later mortality. RESULTS: Of 1,098 patients, 224 (20%) had died by the end of 2004. All-cause and CVD mortality were increased in rheumatoid factor (RF)-positive patients and in this subgroup, CVD mortality was increased at both early and later followup (SMR 5-year followup 1.93 [95% confidence interval 1.08-3.19]; SMR 10-year followup 2.00 [95% confidence interval 1.37-2.80]). CVD mortality was highest in seropositive patients<55 years of age at disease onset (SMR 5.58 [95% confidence interval 2.24-11.50]). In multivariate models, age at onset, male sex, RF positivity, Health Assessment Questionnaire score>or=1.5, and nodules were predictors of early and later mortality. CONCLUSION: Patients with IP had higher rates of CVD mortality throughout the followup period studied, and this was highest in seropositive patients who were <55 years of age at symptom onset. This subgroup deserves particular attention in terms of disease and risk factor modification. Nodules were independent predictors of CVD mortality, suggesting that extraarticular/vascular inflammation identifies patients at particularly high CVD risk.     

Association of infections and tuberculosis with antitumor necrosis factor alpha therapy

PURPOSE OF REVIEW: Rheumatoid arthritis patients have higher risk for infections due to comorbidities, underlying immunosuppression and use of glucocorticoids and disease modifying antirheumatic drugs. The association between treatment with antitumor necrosis factor alpha agents and serious infections, including opportunistic infections such as tuberculosis, in rheumatoid arthritis patients remains controversial. We present recent literature on this topic with a focus on clinical applications of this new data. RECENT FINDINGS: Prospective cohort studies and population-based registries have described the incidence and risk of serious infections in large rheumatoid arthritis patient populations of antitumor necrosis factor alpha users. Although some studies have suggested a one and one-half to two-fold increased risk, especially immediately after initiating the treatment, not all have shown an elevated risk for serious bacterial infections or tuberculosis. SUMMARY: Although antitumor necrosis factor alpha agents may be independent risk factors for infections there is an absolute low rate of infection in those treated with these agents (approximately 5 per 100 patient-years). Screening for latent tuberculosis with tuberculin skin testing is effective, and compliance with the recommendations for preventing this disease in recipients of antitumor necrosis factor alpha agents has partially decreased the risk of infections. Clinical suspicion toward developing infection in those being treated with antitumor necrosis factor alpha agents, particularly earlier in the treatment course, is important for effective management of patients.     

Infections preceding early arthritis in southern Sweden: a prospective population-based study

OBJECTIVE: To detect evidence of infections preceding early arthritis in Southern Sweden and to compare the clinical outcome of remission during a 6-month followup for patients with and without signs of prior infection. METHODS: Adult patients with arthritis of less than 3 months' duration were referred from primary health care centers to rheumatologists. All patients were systematically screened for infections caused by Salmonella typhimurium and Salmonella enteritidis, Yersinia enterocolitica, Campylobacter jejuni, Borrelia burgdorferi, Chlamydia trachomatis, Chlamydia pneumoniae, and parvovirus B19. RESULTS: Seventy-one patients were included in this study. Twenty-seven (38%) patients had reactive arthritis (ReA), 17 (24%) undifferentiated arthritis, 15 (21%) rheumatoid arthritis (RA), 4 (6%) psoriatic arthritis, and the rest (11%) other diagnoses. Of all the patients, 45% had evidence of a recent infection preceding the arthritis, as indicated by laboratory tests and/or disease history. C. jejuni dominated the ReA group. The occurrence of recent C. trachomatis, B. burgdorferi, C. pneumoniae, and parvovirus B19 infections was low. Overall, 58% of the patients went into remission during the 6-month followup. Of the patients with a preceding infection, 69% went into remission as compared to 38% of the patients without a preceding infection (p = 0.011). Thirty-three percent of the patients with RA were in remission after 6 months. CONCLUSION: In this population-based cohort, 45% of the patients presenting with a new-onset arthritis had had a prior infection. Campylobacter ReA dominated the ReA group. There were only a few cases preceded by infections by C. trachomatis, B. burgdorferi, C. pneumoniae, and parvovirus B19 infections. Remission during the first 6 months was especially frequent in the group of patients with a prior infection, but the remission rate was relatively high even for arthritis without prior infection.     

Anemia in early rheumatoid arthritis is associated with interleukin 6-mediated bone marrow suppression, but has no effect on disease course or mortality

OBJECTIVE: Anemia of chronic disease (ACD) is the most common extraarticular manifestation of rheumatoid arthritis (RA), but there is limited information on the cause and consequences of ACD. We investigated the prevalence, relation with proinflammatory cytokines, and effect on disease outcome of ACD in patients with RA. METHODS: The presence of anemia was analyzed in a cohort of 111 consecutive patients with early RA. Anemia was related to markers of erythropoiesis and inflammation [clinically and by levels of erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and serum interleukin 1beta (IL-1beta), IL-2, IL-6, IL-8, and tumor necrosis factor-alpha]. The frequency of various disease outcomes during the mean followup of 74 months was compared between ACD and nonanemic patients. RESULTS: ACD was present in 25% during the first year of disease. ACD was associated with higher CRP (45 vs 22 g/l; p = 0.04) and ESR levels (54 vs 33 mm/h; p = 0.002). Hemoglobin levels were inversely correlated with serum erythropoietin (p = 0.003) in univariate analysis, but in multivariate analysis only ESR (p = 0.005) and IL-6 (p = 0.056) remained as independent predictors of hemoglobin levels. Presence of ACD was not associated with later development of disease manifestations or mortality. CONCLUSION: While ACD affected 25% of patients with RA early in the disease course, this had no influence on disease outcome including mortality during the following 6 years. The association between IL-6 and ACD suggests that IL-6-mediated bone marrow suppression is the main mechanism for development of ACD in RA.     

Association of HLA-C3 and smoking with vasculitis in patients with rheumatoid arthritis

OBJECTIVE: To compare HLA-C genotypes and smoking habits in patients with vasculitis or other severe extraarticular manifestations of rheumatoid arthritis (ExRA) with those in RA patients without extraarticular disease. METHODS: Patients were recruited from a large research database of patients with RA at the Mayo Clinic, from 2 Swedish cohorts of prevalent RA cases, and from a regional Swedish early RA cohort. Patients with severe ExRA (n = 159) and control patients with RA but no history of ExRA (non-ExRA controls) (n = 178) were matched for duration of RA and for clinical center. Data on smoking at RA onset, rheumatoid factor (RF) status, and antinuclear antibodies (ANAs) were extracted from the medical records. Polymerase chain reaction-based HLA-C genotyping was performed using a sequence-specific primer kit. RESULTS: The distribution of HLA-C alleles was significantly different between patients with RA-associated vasculitis and non-ExRA controls (P = 0.014). This was mainly due to a positive association of the HLA-C3 allele with vasculitis (allele frequency 0.411 in vasculitis patients versus 0.199 in non-ExRA controls; P < 0.001) and a decreased frequency of HLA-C7 (0.122 and 0.243, respectively; P = 0.018). The association between HLA-C3 and vasculitis was not due to linkage disequilibrium with HLA-DRB1. Smoking (P = 0.001), RF positivity (P < 0.0001), and presence of ANAs (P < 0.0001) were all associated with ExRA. HLA-C3 and smoking were both significant predictors of vasculitis in a multivariate model. CONCLUSION: Vasculitis in RA is associated with HLA-C3. Smoking is an independent predictor of vasculitis and other types of severe ExRA. Our results suggest that these variables are among the genetic and environmental factors that contribute significantly to the pathomechanisms of systemic RA.     

How much of the increased incidence of heart failure in rheumatoid arthritis is attributable to traditional cardiovascular risk factors and ischemic heart disease?

OBJECTIVE: To compare the proportion of the risk for the development of heart failure (HF) that is attributable to traditional cardiovascular (CV) risk factors, ischemic heart disease (IHD), and alcohol abuse between subjects with and subjects without rheumatoid arthritis (RA). METHODS: A population-based inception cohort of RA patients was assembled along with a similar cohort of subjects without RA. All individuals were followed up through their complete medical records, until HF incidence, death, migration, or January 1, 2001. The attributable risk of HF was estimated as the difference between the observed cumulative incidence of HF in each cohort (estimated from multivariable Cox models and adjusted for the competing risk of death) and the predicted cumulative incidence of HF in the absence of risk factors, with results expressed as a percentage of the observed cumulative incidence. RESULTS: A total of 575 RA subjects and 583 non-RA subjects (mean age 57 years, 73% women) without HF at incidence/index date had a mean followup of 15.1 and 17.0 years, respectively. During that period, 165 RA and 115 non-RA subjects had a first episode of HF, with a cumulative incidence of 36.3% and 20.4%, respectively, at age 80 years. Among non-RA subjects, 77% of the HF at age 80 years was attributable to CV risk factors, IHD, and alcohol abuse combined, whereas among RA subjects, only 54% of the HF at age 80 years was attributable to these factors (P < 0.01). CONCLUSION: The excess risk of HF among RA patients is not explained by an increased frequency or effect of CV risk factors and IHD.     

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.