Patient self-report tender and swollen joint counts in early rheumatoid arthritis. Western Consortium of Practicing Rheumatologists

OBJECTIVE: To determine the correlation between patient self-report joint counts and standard physician joint counts, and to compare pictorial (Mannequin) and text (Rapid Assessment of Disease Activity in Rheumatology, RADAR) formats for obtaining patient self-reports. METHODS: Baseline patient self-report joint counts were mailed and completed by 60 patients with early rheumatoid arthritis (RA) one day before and one day after being examined by a physician. Twenty-seven were randomized to the Mannequin tender and Mannequin swollen joint counts; 33 were randomized to the RADAR tender and swollen joint counts. Agreement between patient and physician self-report joint counts, diagnostic characteristics, and test-retest reliability of patient self-report joint counts was computed. Stepwise regression analyses were performed to identify predictors of patient-physician differences in total joint count. RESULTS: Means and standard deviations of paired patient and physician total joint counts were not different for Mannequin or RADAR forms. Spearman correlations were moderate (0.58 to 0.69 for Mannequin, 0.37 to 0.58 for RADAR). Agreement (intraclass correlations) was 0.65 for the Mannequin and 0.56 for the RADAR forms. Patient test-retest reproducibility was moderate for RADAR tenderness (0.58) and high (r>0.90) for RADAR swollen and both Mannequin forms. Level of patient education predicted patient-physician differences on the RADAR swollen joint counts (p = 0.003), but was not significant in Mannequin forms, suggesting that education was not a factor in accurate completion of Mannequin forms. CONCLUSION: Both pictorial and text format patient self-report joint counts are significantly correlated with physician joint counts. In addition to moderately high patient test-retest reproducibility, this suggests that patient self-reports in both formats may yield accurate measures of improvement in disease activity.     

Prediction of 20-year outcome at onset of seropositive rheumatoid arthritis

OBJECTIVE: With the advent of new and expensive antirheumatic treatments with potentially serious side effects, it would be essential to identify as early as possible those rheumatoid arthritis (RA) patients who have a poor prognosis. Here study was made of the prognostic value of different markers recorded at the onset of RA. METHODS: At the 20-year follow-up of our prospective study, 66 patients had rheumatoid factor-positive (RF+) RA. At commencement of follow-up (disease duration < 6 months), the prognostic value of 19 demographic, laboratory, clinical and radiographic variables was tested to explain the 20-year Larsen score for peripheral joints and the Health Assessment Questionnaire (HAQ) index using Somers'd for asymmetrical associations. RESULTS: An association was observed between onset blood platelets (0.17), serum IgG (0.18), the onset Larsen score (0.33) and the 20-year Larsen score. Old age (0.30), serum orosomucoid (0.17), the function score (0.28), morning stiffness (0.28), and grip strength (0.24) were associated with the 20-year HAQ. CONCLUSION: The correlation between the investigated entry variables and end-point outcome was poor. In our discussion we conclude that the most important prognostic factor in RF + RA is the treatment.     

Direct medical costs and their predictors in patients with rheumatoid arthritis

Objective

To estimate total direct medical costs in persons with rheumatoid arthritis (RA) and to characterize predictors of these costs.

Methods

Patients (n = 7,527) participating in a longitudinal study of outcome in RA completed 25,050 semiannual questionnaires from January 1999 through December 2001. From these we determined direct medical care costs converted to 2001 US dollars using the consumer price index. We used generalized estimating equations to examine potential predictors of the costs. Monte Carlo simulations and sensitivity analyses were performed to evaluate the varying prevalence and cost of biologic therapy.

Results

The mean total annual direct medical care cost in 2001 for a patient with RA was $9,519. Drug costs were $6,324 (66% of the total), while hospitalization costs were only $1,573 (17%). Approximately 25% of patients received biologic therapy. The mean total annual direct cost for patients receiving biologic agents was $19,016 per year, while the cost for those not receiving biologic therapy was $6,164. RA patients who were in the worst quartile of functional status, as measured by the Health Assessment Questionnaire, experienced direct medical costs for the subsequent year that were $5,022 more than the costs incurred by those in the best quartile. Physical status as determined by the Short Form 36 physical component scale had a similar large effect on RA costs, as did comorbidity. Medical insurance type played a more limited role. However, those without insurance had substantially lower service utilization and costs, and health maintenance organization patients had lower drug costs and total medical costs. Increased years of education, increased income, and majority ethnic status were all associated with increased drug costs but not hospitalization costs. Costs in all categories decreased after age 65 years.

Conclusion

Estimates of direct medical costs for patients with RA are substantially higher than cost estimates before the biologic therapy era, and costs are now driven predominantly by the cost of drugs, primarily biologic agents. RA patients with poor function continue to incur substantially higher costs, as do those with comorbid conditions, and sociodemographic characteristics also play an important role in determination of costs.

     

A comparison of patients with seropositive and seronegative rheumatoid arthritis

Summary It has recently been suggested that a subpopulation of patients with rheumatoid arthritis, diagnosed on clinical, radiologic and pragmatic grounds, but with negative rheumatoid factor tests, represents a clinical entity quite distinct from that of seropositve rheumatoid arthritis. We have studied 60 sequentially presenting patients, 30 of whom were selected because they were seronegative, and 30 selected because they were seropositive in regard to IGM rheumatoid factor. The only major differences detected between the two groups on blind assessment were a greater tendency to deformity, a greater degree of erosion and the presence of subcutaneous nodules in the seropositive group. Seronegative and seropositive rheumatoid arthritis appear to have very similar clinical features, but differing degrees of severity.     

Modeling the lifetime costs of rheumatoid arthritis.

OBJECTIVE: To develop an analytical approach for estimating the lifetime costs of rheumatoid arthritis (RA) using existing population based cross sectional data, and to use this estimate to describe the potential cost-effectiveness of bone marrow transplantation for RA. METHODS: Estimates of arthritis related costs (direct, indirect, and nonmedical) and mortality were obtained from previously assembled population based cohorts. A mathematical model was designed defining 25 hypothetical ratios (RA/NA) representing the proportionate excess cost of RA each year for the 25 years following a diagnosis of RA. Using age and sex-specific cost estimates, we then simulated a vector of 25 ratios 1000 times. Each age and sex-specific randomly generated variable was converted to an estimated dollar amount (in 1995 dollars US) of excess cost attributable to RA. All dollar amounts were discounted by 3% per year. Finally, each vector of 25 discounted dollar amounts was summed to yield an estimate of the total excess medical costs in 1995 dollars for the first 25 years of a person's lifetime following a diagnosis of RA. Because not every one of these hypothetical individuals would be expected to live all 25 years, we used the standardized mortality ratio for an individual with RA (from our inception cohort) and multiplied it by the age-specific 1990 mortality rates for Minnesota whites to estimate how many of the 1000 randomly generated hypothetical individuals could be expected to die during each of the 25 years. For these, the summation of estimated cost was truncated at the death year. This process yielded, for each age and sex, a sample of 1000 sums of 25 (or fewer) excess costs all in terms of 1995 dollars that correspond to the excess cost during the first 25 years after an RA diagnosis, adjusted for differential survival among patients with RA compared to nonarthritic controls. The distribution of these sums thus represented a distribution of the 1995 dollars that could be saved if RA could be "cured" soon after incidence. RESULTS: Our simulation analyses indicated that the median lifetime incremental costs of RA range roughly from ,$61,000 to $ 122,000. Incremental costs were higher for younger individuals compared to older individuals and were consistent over all percentiles and age groups. No systematic relationship between the incremental costs of females with RA compared to males was identified. CONCLUSION: These data suggest that interventions such as autologous bone marrow transplantation, which has recently been estimated to cost roughly $60,000, may be cost saving if they eliminate the downstream incremental costs of RA.     

Equivalence of the acute phase reactants C-reactive protein, plasma viscosity, and Westergren erythrocyte sedimentation rate when used to calculate American College of Rheumatology 20% improvement criteria or the Disease Activity Score in patients with early rheumatoid arthritis. Western Consortium of Practicing Rheumatologists.

OBJECTIVE: In an additive cohort of patients with early rheumatoid arthritis (RA), to determine the effect of substituting one acute phase reactant for another on the number of patients satisfying the American College of Rheumatology (ACR) 20% preliminary criteria for improvement, and on calculated Disease Activity Scores (DAS). METHODS: A total of 251 patients with 6.4 months average disease duration had detailed clinical assessments at entry and 6, 12, and 24 months in a multicenter prospective longterm observational study. Matched erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and plasma viscosity (PV) assays were done at 366 time points. Disease modifying antirheumatic drugs were not started until after the baseline evaluation. RESULTS: After 6, 12, and 24 months, 50%, 53%, and 57% of patients were responders, as defined by the ACR 20% improvement criteria. The difference in response rates when ESR, CRP, or PV was used as the acute phase reactant ranged from 0.4% at 12 months to 3% at 24 months. Percentile distributions of the 366 matched CRP, ESR, and PV values were used to prepare a nomogram that can be used to calculate the other acute phase reactant values if the value of one is known. When the nomogram was used to impute ESR values from observed PV or CRP values, average DAS scores calculated with the actual ESR values were not different from average DAS scores calculated from the imputed ESR values. CONCLUSION: ESR, CRP, and PV are equally useful in calculating ACR 20% response rates in patients with active early RA. A nomogram can be used to impute ESR values from CRP or PV values; use of the imputed ESR values is as accurate as use of the actual ESR values to calculate average DAS.     

Articular chondrocalcinosis in seropositive rheumatoid arthritis. Comparison with a control group

The prevalence of articular chondrocalcinosis was studied in a group of 100 patients with seropositive rheumatoid arthritis (RA). Articular chondrocalcinosis was observed less frequently (3%) than in a control group (19%) of 221 age and sex matched patients with low back pain or extraarticular rheumatism. This difference is statistically significant (p less than 0.001). Articular chondrocalcinosis occurred in the older patients with RA, and was observed in those with the shortest duration of the disease.     

IgG rheumatoid factor. Relationship to seropositive rheumatoid arthritis and absence in seronegative disorders.

IgG rheumatoid factor was detected in the sera of the majority of patients with seropositive rheumatoid arthritis. Values suggestive of IgG rheumatoid factor were noted in one-quarter of patients with seronegative inflammatory arthropathies. These determinations were always low and correlated with elevated IgG concentrations, suggesting nonspecific adherence of IgG rather than a true antigen-antibody reaction. In support of this conclusion, nonrheumatoid factor IgG was capable of concentration-dependent nonspecific adsorption to the solid phase. IgG, but not IgM, rheumatoid factor corresponded with disease activity in patients with seropositive rheumatoid arthritis, suggesting that IgG rheumatoid factor may be important in the pathogenesis.     

Breast-feeding and the onset of rheumatoid arthritis

Objective. In a recent study we demonstrated that the postpartum period, particularly after the first pregnancy, is a time of increased risk for the development of rheumatoid arthritis (RA). The present study was undertaken to investigate whether this risk might be explained by breast-feeding. Methods. Through a nationwide media campaign, we identified 187 women who had developed RA within 12 months of a pregnancy, and we compared their breast-feeding histories with those of 149 similarly aged women chosen from the patient registers of a nationwide group of general practitioners. Results. In all, 88 of the women with RA developed the disease after their first pregnancy. Eighty-one percent of these 88 women had breast-fed. This was higher than the breast-feeding prevalence of 50% in the 129 controls whose first pregnancy had resulted in a live birth (adjusted odds ratio [OR] 5.4, 95% confidence interval 2.5–11.4). There was a smaller increased risk of breast-feeding after a second pregnancy in the RA cases (OR 2.0) and no increase after a third pregnancy (OR 0.6). The increase in risk was greatest in those cases whose disease was erosive and who were rheumatoid factor positive. Conclusion. In a small group of susceptible women, exposure to breast-feeding after the first pregnancy is associated with a significant increase in risk for RA development. We postulate that this may reflect hormonal influences, specifically the high level of the proinflammatory hormone prolactin.     

Follicular bronchiolitis associated with rheumatoid arthritis.

Follicular bronchiolitis is a rare disorder, though it has been recognized as a pulmonary involvement of rheumatoid arthritis in recent years. A 57-year-old woman with rheumatoid arthritis was admitted to the hospital with persistent productive cough and breathlessness on exertion. An open lung biopsy was performed to establish a definite pathologic diagnosis of her disease, and she was diagnosed as having follicular bronchiolitis on the basis of the histopathological findings. It is essential to differentiate this disease from other bronchiolar or lymphoproliferative disorders of the lung.     

Older age onset rheumatoid arthritis with or without osteoarthritis.

The clinical features of a group of 79 patients with older age onset rheumatoid arthritis (ORA) were compared with those of a group of 414 patients with younger age onset rheumatoid arthritis. The ORA group contained approximately equal numbers of men and women, were less rheumatoid factor positive, had a raised erythrocyte sedimentation rate, lower HLA-DR4 positivity, and a tendency towards larger joint involvement at the onset of the disease. These features have been reported by many authors except for the lower DR4 positivity. Of these features, the lower prevalence of rheumatoid factor positivity and the tendency towards larger joint involvement at the onset were characteristic of a subset of patients with ORA who had had osteoarthritis before the onset of rheumatoid arthritis. It is suggested that osteoarthritic large joints may be susceptible to the occurrence of rheumatoid synovitis at the onset of the disease, but that the osteoarthritis inducing factor may be negatively related to the progression of rheumatoid arthritis.