Jessica Widdifield

Serious infections in a population‐based cohort of 86,039 seniors with rheumatoid arthritis

To assess risk and risk factors for serious infections in seniors with rheumatoid arthritis (RA) using a case–control study nested within an RA cohort.

The epidemiology of rheumatoid arthritis in Ontario, Canada.

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.

Accuracy of Canadian Health Administrative Databases in Identifying Patients With Rheumatoid Arthritis: A Validation Study Using the Medical Records of Rheumatologists

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.

Trends in Excess Mortality Among Patients With Rheumatoid Arthritis in Ontario, Canada.

To evaluate excess mortality over time, comparing rheumatoid arthritis (RA) patients with the general population.

Comparison of Anti-TNF Treatment Initiation in Rheumatoid Arthritis Databases Demonstrates Wide Country Variability in Patient Parameters at Initiation of Anti-TNF Therapy

OBJECTIVE Characteristics of Canadian RA patients started on anti-tumor necrosis factor (TNF) treatment were compared with 12 other countries. METHODS Data from the Optimization of HUMIRA trial (OH) were compared with Canadian real world studies [Ontario Biologics Research Initiative (OBRI) and the Real-Life Evaluation of Rheumatoid Arthritis in Canadians Receiving HUMIRA (REACH)], and to data from American, Australian, British, Czech, Danish, Dutch, Finnish, German, Italian, Norwegian, Spanish, and Swedish RA databases. Patient characteristics and temporal trends at initiation of anti-TNF therapy were compared between countries. RESULTS Baseline Disease Activity Scores (DAS28) varied from 5.3 to 6.6. Lower disease severity was noted in databases from countries with less restrictive anti-TNF coverage: Dutch [based on previous disease-modifying antirheumatic drugs (DMARD) use, DAS28, swollen joint count (SJC), tender joint count (TJC), Health Assessment Questionnaire Disability Index (HAQ-DI), Danish (previous DMARD use, DAS28), Norwegian (DAS28, SJC, TJC, visual analog scale (VAS) of global health), and Swedish (DAS28, SJC, TJC, HAQ-DI)]. RA databases showed lower disease scores than did OH (P < 0.05). The US databases also showed lower disease severity (CORRONA: previous DMARD use, SJC, TJC; National Data Bank for Rheumatic Diseases: HAQ, P < 0.001). The UK and Czech Republic had restrictive coverage and higher mean baseline DAS28 than OH (P < 0.001). Baseline DAS28 in the registries with published data lowered over time (British, Norwegian, Danish, and Swedish) but less for the British (P < 0.001). CONCLUSIONS These results confirm that regional variation exists between the 13 countries analyzed in the initiation of treatment with anti-TNF agents among RA patients and suggest that in some cases this variation may be increasing. In some countries the mean baseline disease severity declined over time and regional reimbursement policies and differences in physician preferences may be influencing initiation of anti-TNF therapy in RA.

Quality care in seniors with new-onset rheumatoid arthritis: A Canadian perspective†

To estimate the percentage of seniors with rheumatoid arthritis (RA) receiving disease‐modifying antirheumatic drugs (DMARDs) within the first year of diagnosis.

Systematic Review and Critical Appraisal of Validation Studies to Identify Rheumatic Diseases in Health Administrative Databases

To evaluate the quality of the methods and reporting of published studies that validate administrative database algorithms for rheumatic disease case ascertainment.

Epidemiology of myasthenia gravis in Ontario, Canada.

Incidence and prevalence estimates in myasthenia gravis have varied widely. Recent studies based on administrative health data have large sample sizes but lack rigorous validation of MG cases, and have not examined the North American population. Our aim was to explore trends in MG incidence and prevalence for the years 1996-2013 in the province of Ontario, Canada (population 13.5 million). We employed a previously validated algorithm to identify MG cases. Linking with census data allowed for the calculation of crude- and age/sex-standardized incidence and prevalence rates for the years 1996-2013. The regional distribution of MG cases throughout the province was examined. Mean age at the first myasthenia gravis encounter was 60.2 ± 17.1 years. In 2013, there were 3611 prevalent cases in Ontario, and the crude prevalence rate was 32.0/100,000 population. Age- and sex-standardized prevalence rates rose consistently over time from 16.3/100,000 (15.4-17.1) in 1996 to 26.3/100,000 (25.4-27.3) in 2013. Standardized incidence rates remained stable between 1996 (2.7/100,000; 95% CL 2.3-3.0) and 2013 (2.3/100,000; 2.1-2.6). Incidence was highest in younger women and older men, and geographic variation was evident throughout the province. In conclusion, this large epidemiological study shows rising myasthenia gravis prevalence with stable incidence over time, which is likely reflective of patients living longer, possibly due to improved disease treatment. Our findings provide accurate information on the Canadian epidemiology of myasthenia gravis and burden for health care resources planning for the province, respectively.

Development and validation of an administrative data algorithm to estimate the disease burden and epidemiology of multiple sclerosis in Ontario, Canada

Background: Few studies have assessed the accuracy of administrative data for identifying multiple sclerosis (MS) patients. Objectives: To validate administrative data algorithms for MS, and describe the burden and epidemiology over time in Ontario, Canada. Methods: We employed a validated search strategy to identify all MS patients within electronic medical records, to identify patients with and without MS (reference standard). We then developed and validated different combinations of administrative data for algorithms. The most accurate algorithm was used to estimate the burden and epidemiology of MS over time. Results: The accuracy of the algorithm of one hospitalisation or five physician billings over 2 years provided both high sensitivity (84%) and positive predictive value (86%). Application of this algorithm to provincial data demonstrated an increasing cumulative burden of MS, from 13,326 patients (0.14%) in 2000 to 24,647 patients in 2010 (0.22%). Age-and-sex standardised prevalence increased from 133.9 to 207.3 MS patients per 100,000 persons in the population, from 2000 – 2010. During this same period, age-and-sex-standardised incidence varied from 17.9 to 19.4 patients per 100,000 persons. Conclusions: MS patients can be accurately identified from administrative data. Our findings illustrated a rising prevalence of MS over time. MS incidence rates also appear to be rising since 2009.

The Rising Burden of Rheumatoid Arthritis Surpasses Rheumatology Supply in Ontario

ObjectivesAccurate data on the burden of rheumatoid arthritis (RA) are scarce, but critical in helping health care providers and decision makers to optimize clinical and public health strategies for disease management. We quantified the burden of RA in Ontario from 1996 to 2010 by age, sex and health planning region.MethodsWe used the Ontario Rheumatoid Arthritis administrative Database (ORAD), a validated population-based cohort of all Ontarians with RA, to estimate the crude prevalence and incidence of RA among men and women, and by age group from 1996 to 2010. Burden by area of patient residence and rheumatology supply also were determined.ResultsThe number of RA patients increased over time, from 42,734 Ontarians (0.5%) in 1996 to 97,499 (0.9%) in 2010. On average 5,830 new RA patients were diagnosed each year. In 2010, the burden was higher among females (1.3%) than males (0.5%) and increased with age, with almost half of all RA patients aged 65 years and older. The burden was higher in northern communities (1.0%) than in southern urban areas (0.7%). During the study period, the number of rheumatologists practicing in Ontario remained unchanged (approximately 160).ConclusionOver a 15-year period, the number of RA patients more than doubled with no concomitant increase in the number of practicing rheumatologists. We observed considerable regional variation in burden, with the highest rates observed in the north. Our findings highlight the need for regional approaches to the planning and delivery of RA care in order to manage the growing burden.RésuméObjectifsLes données précises sur le fardeau de la polyarthrite rhumatoïde (PR) sont rares mais essentielles pour aider le personnel soignant et les décideurs à optimiser les stratégies cliniques et de santé publique en gestion des soins thérapeutiques. Nous avons chiffré le fardeau de la PR en Ontario de 1996 à 2010 selon l’âge, le sexe et la région de planification sanitaire.MéthodeNous avons utilisé la base de données administratives sur la polyarthrite rhumatoïde de l’Ontario (ORAD), une cohorte populationnelle validée de tous les Ontariens atteints de PR, pour estimer la prévalence et l’incidence brutes de la PR selon le sexe et le groupe d’âge de 1996 à 2010. Nous avons aussi déterminé le fardeau de la maladie selon la région de résidence des patients et l’offre en rhumatologie.RésultatsLe nombre de patients atteints de PR a augmenté avec le temps, passant de 42 734 Ontariens (0,5%) en 1996 à 97 499 (0,9%) en 2010. En moyenne, 5 830 nouveaux patients par année ont reçu un diagnostic de PR. En 2010, le fardeau était plus lourd chez les femmes (1,3%) que chez les hommes (0,5%), et il augmentait avec l’âge: près de la moitié des patients atteints de PR avaient 65 ans et plus. Le fardeau était plus lourd dans les communautés nordiques (1,0%) que dans les agglomérations urbaines du Sud (0,7%). Sur la période de l’étude, le nombre de rhumatologues exerçant en Ontario est resté inchangé (environ 160).ConclusionSur une période de 15 ans, le nombre de patients atteints de PR a plus que doublé, sans augmentation comparable du nombre de rhumatologues en exercice. Nous avons relevé des écarts régionaux considérables dans le fardeau de la maladie, les plus hauts taux étant observés dans le Nord. Nos constatations soulignent le besoin d’approches régionales en matière de planification et de prestation des soins de la PR afin de composer avec l’alourdissement du fardeau.