Health administrative data can be a valuable tool for disease surveillance and research. Few studies have rigorously evaluated the accuracy of administrative databases for identifying rheumatoid arthritis (RA) patients. Our aim was to validate administrative data algorithms to identify RA patients in Ontario, Canada.
We performed a retrospective review of a random sample of 450 patients from 18 rheumatology clinics. Using rheumatologist-reported diagnosis as the reference standard, we tested and validated different combinations of physician billing, hospitalization, and pharmacy data.
One hundred forty-nine rheumatology patients were classified as having RA and 301 were classified as not having RA based on our reference standard definition (study RA prevalence 33%). Overall, algorithms that included physician billings had excellent sensitivity (range 94-100%). Specificity and positive predictive value (PPV) were modest to excellent and increased when algorithms included multiple physician claims or specialist claims. The addition of RA medications did not significantly improve algorithm performance. The algorithm of "(1 hospitalization RA code ever) OR (3 physician RA diagnosis codes [claims] with =1 by a specialist in a 2-year period)" had a sensitivity of 97%, specificity of 85%, PPV of 76%, and negative predictive value of 98%. Most RA patients (84%) had an RA diagnosis code present in the administrative data within ±1 year of a rheumatologist's documented diagnosis date.
We demonstrated that administrative data can be used to identify RA patients with a high degree of accuracy. RA diagnosis date and disease duration are fairly well estimated from administrative data in jurisdictions of universal health care insurance.
In inflammatory arthritis, rheumatoid factor (RF) and anticitrullinated protein antibodies (ACPA) are believed to be associated with more severe clinical outcomes. Our objective was to determine whether ACPA and RF remain stable in early inflammatory arthritis and whether their trajectories over time or baseline levels predicted clinical outcomes.
The study population consisted of patients enrolled in the Canadian Early Arthritis Cohort Study with baseline and at least 12-month followup values of RF and ACPA. Primary outcomes were Disease Activity Score (DAS) remission and the presence of erosions at 12 and 24 months. Other objectives included swollen joint count, Health Assessment Questionnaire score, and DAS.
At baseline, 225/342 (66%) patients were ACPA-positive and 334/520 (64%) were RF-positive. At 24 months, 15/181 (8%) ACPA-positive patients became negative. A larger number of patients changed from ACPA-negative to positive: 13/123 (11%). For RF, fluctuations were more common: 67/240 (28%) reverted from positive to negative and 21/136 (18%) converted from negative to positive. RF and ACPA fluctuations did not predict disease outcomes. Patients who remained ACPA-positive throughout followup were more likely to have erosive disease (OR 3.86, 95% CI 1.68, 8.92).
RF and ACPA have the potential to revert and convert during the early course of disease. Fluctuations in RF and ACPA were not associated with clinical outcomes.
The Canadian Early Arthritis Cohort (CATCH): patients with new-onset synovitis meeting the 2010 ACR/EULAR classification criteria but not the 1987 ACR classification criteria present with less severe disease activity.
Our objective was to describe characteristics of Canadian patients with early arthritis and examine differences between those fulfilling 1987 and 2010 rheumatoid arthritis (RA) classification criteria.
The Canadian Early Arthritis Cohort (CATCH) is a national, multicenter, observational, prospective cohort of patients with early inflammatory arthritis, receiving usual care, recruited since 2007. Inclusion criteria include age > 16 years; symptom duration 6-52 weeks; swelling of = 2 joints or = 1 metacarpophalangeal/proximal interphalangeal joint; and 1 of rheumatoid factor = 20 IU, positive anticitrullinated protein antibodies (ACPA), morning stiffness = 45 min, response to nonsteroidal antiinflammatory drug, or positive metatarsophalangeal joint squeeze test. Data from patients enrolled to March 15, 2011, were analyzed.
In total, 1450 patients met the eligibility criteria (1187 were followed). At baseline, mean age was 53 ± 15 years, symptom duration was 6.1 ± 3.2 months, Disease Activity Score (DAS28) was 4.9 ± 1.6, Health Assessment Questionnaire-Disability Index was 1.0 ± 0.7. Forty-one percent (n = 450) of patients had moderate (3.2 5.1) disease activity; 28% of those with baseline radiographs (n = 250/908) had radiographic evidence of erosions. ACPA status was available for 70% (n = 831) of patients; 55% (n = 453) tested positive. Sixty percent (n = 718) of patients were treated with methotrexate (MTX) initially. Of 612 patients without erosions, 63% and 83% fulfilled 1987 and 2010 RA classification criteria, respectively. Seventy-three percent (n = 166) of those who did not fulfill 1987 criteria were newly identified by the 2010 criteria. These patients had less severe disease and more were MTX-naive compared to those satisfying the 1987 criteria. Forty-seven percent of all patients achieved remission at 1 year.
Patients with early RA present with moderate high disease activity;
Current clinical trial designs for pharmacologic interventions in rheumatoid arthritis (RA) do not reflect the innovations in RA diagnosis, treatment, and care in countries where new drugs are most often used. The objective of this project was to recommend revised entry criteria and other study design features for RA clinical trials.
Recommendations were developed using a modified nominal group consensus method. Canadian Rheumatology Research Consortium (CRRC) members were polled to rank the greatest challenges to clinical trial recruitment in their practices. Initial recommendations were developed by an expert panel of rheumatology trialists and other experts. A scoping study methodology was then used to examine the evidence available to support or refute each initial recommendation. The potential influence of CRRC recommendations on primary outcomes in future trials was examined. Recommendations were finalized using a consensus process.
Recommendations for clinical trial inclusion criteria addressed measures of disease activity [Disease Activity Score 28 using erythrocyte sedimentation rate (DAS28-ESR) > 3.2 PLUS = 3 tender joints using 28-joint count (TJC28) PLUS = 3 swollen joint (SJC28) OR C-reactive protein (CRP) or ESR > upper limit of normal PLUS = 3 TJC28 PLUS = 3 SJC28], functional classification, disease classification and duration, and concomitant RA treatments. Additional recommendations regarding study design addressed rescue strategies and longterm extension.
There is an urgent need to modify clinical trial inclusion criteria and other study design features to better reflect the current characteristics of people living with RA in the countries where the new drugs will be used.
From the Rheumatology Centre, St. Joseph's Health Care, London, Ontario, Canada; the Hospital for Special Surgery, New York, New York, USA; the Arthritis Centre, University of Manitoba, Winnipeg, Manitoba; the University of Toronto, Toronto; Southlake Regional Health Centre, Newmarket, Ontario; the Faculty of Medicine and Health Sciences, Division of Rheumatology, Université de Sherbrooke, Sherbrooke, Quebec; the Rheumatic Disease Unit, Institut de Rhumatologie, Montreal, Quebec; McMaster University, Hamilton, Ontario; and Western University, London, Ontario, Canada.
To determine site variation by comparing outcomes across sites in an early rheumatoid arthritis cohort.
Sites from the Canadian Early Arthritis Cohort database with at least 40 patients were studied. Comparisons were made among sites in change in 28-joint Disease Activity Score (DAS28), proportion of patients in DAS28 remission, and treatment strategies.
The study included 1138 baseline patients at 8 sites, with baseline (SD) age 52 years (16.9); 72% women; 23% erosions; 54% ever smokers; 51% rheumatoid factor-positive; 37% anticitrullinated protein antibody-positive; disease duration 187 (203) days; DAS28 4.5 (1.4). Site had an effect on outcomes when adjusting for confounders. At 6 and 12 months, sites B and H, the 2 largest sites, had the best changes in DAS28 (-1.82 and -2.09, respectively, at 6 mos, and -2.27 for both at 12 mos; p
Epidemiologic assessments of sufficiently large populations are required in order to obtain robust estimates of disease prevalence and incidence, particularly when exploring the influence of various factors (age, sex, calendar time). We undertook this study to describe the epidemiology of rheumatoid arthritis (RA) over the past 15 years.
We used the Ontario Rheumatoid Arthritis administrative Database (ORAD), a validated population-based research database of all Ontarians with RA. The ORAD records were linked with census data to calculate crude and age and sex-standardized prevalence and incidence rates from 1996 to 2010. Vital statistics were used to estimate annual all-cause mortality during the study period.
As of 2010, there were 97,499 Ontarians with RA, corresponding to a cumulative prevalence of 0.9%. Age and sex-standardized RA prevalence increased steadily over time from 473 (95% confidence interval [95% CI] 469-478) per 100,000 population (0.49%) in 1996 to 784 (95% CI 779-789) per 100,000 population (0.9%) in 2010. Age and sex-standardized incidence per 100,000 population ranged from 62 (95% CI 60-63) in 1996 to 54 (95% CI 52-55) in 2010. All-cause mortality decreased by a relative 21.4% since 1996.
Over a 15-year period, we observed an increase in RA prevalence over time. This rise may be attributed to the increasing time to ascertain cases (which may have been latent in the population during earlier years of the study), increasing survival, and/or an increase in the aging background population. Incidence appears to be stable.
Secondary fibromyalgia (FM) is common among patients with inflammatory arthritis, but little is known about its incidence and the factors leading to its development. The authors examined the incidence of secondary FM in an early inflammatory arthritis cohort, and assessed the association between pain, inflammation, psychosocial variables and the clinical diagnosis of FM.
Data from 1487 patients in the Canadian Early Arthritis Cohort, a prospective, observational Canadian cohort of early inflammatory arthritis patients were analysed. Diagnoses of FM were determined by rheumatologists. Incidence rates were calculated, and Cox regression models were used to determine HRs for FM risk.
The cumulative incidence rate was 6.77 (95% CI 5.19 to 8.64) per 100 person-years during the first 12 months after inflammatory arthritis diagnosis, and decreased to 3.58 (95% CI 1.86 to 6.17) per 100 person-years 12-24 months after arthritis diagnosis. Pain severity (HR 2.01, 95% CI 1.17 to 3.46) and poor mental health (HR 1.99, 95% CI 1.09 to 3.62) predicted FM risk. Citrullinated peptide positivity (HR 0.48, 95% CI 0.26 to 0.88) was associated with decreased FM risk. Serum inflammatory markers and swollen joint count were not significantly associated with FM risk.
The incidence of FM was from 3.58 to 6.77 cases per 100 person-years, and was highest during the first 12 months after diagnosis of inflammatory arthritis. Although inflammation was not associated with the clinical diagnosis of FM, pain severity and poor mental health were associated with the clinical diagnosis of FM. Seropositivity was inversely associated with the clinical diagnosis of FM.
To determine the factors most strongly associated with an increase in therapy of early rheumatoid arthritis (ERA).
Data from the Canadian Early Arthritis Cohort (CATCH) were included if the patient had = 2 visits and baseline and 6 months data. A regression analysis was done to determine factors associated with treatment intensification.
Of 1145 patients with ERA, 790 met inclusion criteria; mean age was 53.4 years (SD 14.7), mean disease duration 6.1 months (SD 2.8), 75% were female, baseline Disease Activity Score-28 (DAS28) was 4.7 (SD 1.8) and 2.9 (SD 1.8) at 6 months for included patients. Univariate factors for intensifying treatment were physician global assessment (MDGA; OR 7.8 and OR 7.4 at 3 and 6 months, respectively, p
We determined the prevalence of work disability in early rheumatoid arthritis (ERA) and undifferentiated early inflammatory arthritis (EIA) patients at first enrollment into the Canadian Early Arthritis Cohort (CATCH) who met the 2010 ACR criteria versus those not meeting criteria, to determine the impact of meeting new criteria on work disability status. Data at first visit into the cohort were analyzed. Descriptive statistics and logistic regression analyses were performed to investigate the association of other variables in our database with work disability. 1,487 patients were enrolled in the CATCH study, a multi-site observational, prospective cohort of patients with EIA. 934 patients were excluded (505 based on missing criteria for ACR 2010 classification, as anti-CCP was absent, and 429 were not working for other reasons). Of the 553 patients included, 71 % were female with mean disease duration of 6.4 months. 524 (94.8 %) were employed while 29 (5.2 %) reported work disability at first visit. There were no differences between those meeting 2010 ACR criteria versus those who did not. Baseline characteristics associated with work disability were male gender, age, education, income, HAQ, and positive RF status. The mean HAQ score in work disabled patients was 1.4 versus 0.9 in those who were working (p 50 years; p = 0.3), lower education (p = 0.3) or RF positivity (p = 0.6). We found rates of work disability to be low at entry into this EIA cohort compared to previous studies. There may be potential for intervention in ERA to prevent the development of work disability.
To estimate the percentage of seniors with rheumatoid arthritis (RA) receiving disease-modifying antirheumatic drugs (DMARDs) within the first year of diagnosis.
We assembled an incident RA cohort from Ontario physician billing data for 1997-2006. We used a standard algorithm to identify 24,942 seniors with RA based on = 2 billing codes = 60 days apart but within 5 years. Drug exposures were obtained from pharmacy claims data. We followed subjects for 1 year, assessing if they had been exposed (defined as = 1 prescription) to 1 or more DMARDs within the first year of RA diagnosis. We assessed secular trends and differences for subjects who had received rheumatology care (defined as = 1 rheumatology encounter) versus those who had not.
In total, only 39% of the 24,942 seniors with new-onset RA identified over 1997-2006 were exposed to DMARD therapy within 1 year of diagnosis. This increased from 30% in 1997 to 53% in 2006. Patients whose care involved a rheumatologist were more likely to be exposed to DMARDs than those who had no rheumatology care. In 2006, 67% of subjects receiving rheumatology care were exposed to DMARDs versus 21% of those with no rheumatology care.
Improvements in RA care have occurred, but more efforts are needed. Subjects receiving rheumatology care are much more likely to receive DMARDs as compared to those with no rheumatology care. This emphasizes the key role of rheumatologists.