Prevalence of autoimmune inflammatory myopathy in the first nations population of Alberta, Canada

Idiopathic inflammatory myopathies

Idiopathic inflammatory myopathies (IIM), also known as myositis, are a heterogeneous group of autoimmune disorders with varying clinical manifestations, treatment responses and prognoses. Muscle weakness is usually the classical clinical manifestation but other organs can be affected, including the skin, joints, lungs, heart and gastrointestinal tract, and they can even result in the predominant manifestations, supporting that IIM are systemic inflammatory disorders. Different myositis-specific auto-antibodies have been identified and, on the basis of clinical, histopathological and serological features, IIM can be classified into several subgroups - dermatomyositis (including amyopathic dermatomyositis), antisynthetase syndrome, immune-mediated necrotizing myopathy, inclusion body myositis, polymyositis and overlap myositis. The prognoses, treatment responses and organ manifestations vary among these groups, implicating different pathophysiological mechanisms in each subtype. A deeper understanding of the molecular pathways underlying the pathogenesis and identifying the auto-antigens of the immune reactions in these subgroups is crucial to improving outcomes. New, more homogeneous subgroups defined by auto-antibodies may help define disease mechanisms and will also be important in future clinical trials for the development of targeted therapies and in identifying biomarkers to guide treatment decisions for the individual patient.

Understanding the Disproportionate Burden of Rheumatic Diseases in Indigenous North American Populations

Studies have described a high incidence and prevalence of several rheumatic diseases in indigenous North American populations. Conditions studied most frequently with consistently high burden of disease include rheumatoid arthritis, spondyloarthritis, and systemic lupus erythematosus. Crystal-induced arthritis has been reported to have a lower prevalence than expected. Information about genetic and environmental risk factors is available for some of these conditions. An awareness of the epidemiology of rheumatic diseases in indigenous North American populations is important for clinicians involved in caring for patients in these populations as well as for planning health service delivery in these communities.

Opportunities and challenges for physical rehabilitation with indigenous populations

Indigenous peoples in colonised countries internationally experience a disproportionately high burden of disease and disability. The impact of many of these conditions, such as musculoskeletal pain, can be ameliorated by participating in physical rehabilitation. However, access by Indigenous peoples to physical rehabilitation is low. Overcoming barriers for Indigenous peoples to access high-quality, effective, culturally secure physical rehabilitation should be a priority. Physical rehabilitation outcomes for Indigenous peoples can be enhanced by addressing health system, health service, and individual clinician-level considerations. System-level changes include a greater commitment to cultural security, improving the funding of physical rehabilitation to Indigenous communities, building the Indigenous physical rehabilitation workforce, and developing and using Indigenous-identified indicators in quality improvement. At the health service level, physical rehabilitation should be based within Indigenous health services, Indigenous people should be employed as physical rehabilitation professionals or in allied roles, and cultural training and support provided to the existing physical rehabilitation workforce. For clinicians, a focus on cultural development and the quality of communication is needed. Indigenous ill-health is complex and includes societal and social influences. These recommendations offer practical guidance toward fair, reasonable, and equitable physical rehabilitation outcomes for Indigenous peoples.

Incidence and Prevalence of Idiopathic Inflammatory Myopathies in Korea: a Nationwide Population-based Study

BACKGROUND

This study aimed to estimate the incidence and prevalence of idiopathic inflammatory myopathies (IIM) and associated comorbidities in Korea from 2006 to 2015.

METHODS

IIM between 2004 to 2015 were identified using the Korean National Health Insurance Service medical claim database. The case definition required more than one visit based on diagnostic codes including juvenile dermatomyositis (JDM), dermatomyositis (DM), or polymyositis (PM) and registration in the Individual Copayment Beneficiaries Program (ICBP) for rare and intractable diseases. IIM patients with a disease-free period of 24 months before the index date were defined as incident cases. The Elixhauser comorbidity score was calculated.

RESULTS

Using the base case definition, 1,150 prevalent patients with IIM (117 JDM, 521 DM, 512 PM) were recorded in 2006 and 2,210 (130 JDM, 1,101 DM, 869 PM) in 2015. The prevalence was estimated at 2.3-4.0 (0.9-1.2 for JDM, 1.2-2.7 for DM, 1.4-2.1 for PM)/100,000 person-year (PY). We identified 218 incident cases of IIM in 2006 (18 JDM, 98 DM, 102 PM) and 191 cases (7 JDM, 83 DM, 101 PM) in 2015. The incidence was estimated at 2.9-5.2 (0.7-1.9 for JDM, 1.8-4.0 for DM, 1.6-3.0 for PM)/1,000,000 PY. The mean age (± standard deviation) of prevalent patients with IIM was 51.2 (± 16.9) years, and the percentage of women was 72.1%. More than two-thirds of patients (70.7%) had more than two comorbidities. Twenty percent of patients had interstitial lung diseases.

CONCLUSION

In Korea, the incidence and prevalence of IIM were 2.9-5.2/1,000,000 PY and 2.3-4.0/100,000 PY, respectively.

Characterization of indigenous community engagement in arthritis studies conducted in Canada, United States of America, Australia and New Zealand

BACKGROUND

Research adhering to community engagement processes leads to improved outcomes. The level of Indigenous communities' engagement in rheumatology research is unknown.

OBJECTIVE

To characterize the frequency and level of community engagement reporting in arthritis studies conducted in Australia (AUS), Canada (CAN), New Zealand (NZ) and the United States of America (USA).

METHODS

Studies identified through systematic reviews on topics of arthritis epidemiology, disease phenotypes and outcomes, health service utilization and mortality in Indigenous populations of AUS, CAN, NZ and USA, were evaluated for their descriptions of community engagement. The level of community engagement during inception, data collection and results interpretation/dissemination stages of research was evaluated using a custom-made instrument, which ranked studies along the community engagement spectrum (i.e. inform-consult-involve-collaborate-empower). Meaningful community engagement was defined as involving, collaborating or empowering communities. Descriptive analyses for community engagement were performed and secondary non-parametric inferential analyses were conducted to evaluate the possible associations between year of publication, origin of the research idea, publication type and region of study; and meaningful community engagement.

RESULTS

Only 34% (n = 69) of the 205 studies identified reported community engagement at ≥ 1 stage of research. Nearly all studies that engaged communities (99% (n = 68)) did so during data collection, while only 10% (n = 7) did so at the inception of research and 16% (n = 11) described community engagement at the results' interpretation/dissemination stage. Most studies provided community engagement descriptions that were assessed to be at the lower end of the spectrum. At the inception of research stage, 3 studies reported consulting communities, while 42 studies reported community consultation at data collection stage and 4 studies reported informing or consulting communities at the interpretation/dissemination of results stage. Only 4 studies described meaningful community engagement through all stages of the research. Inferential statistics identified that studies with research ideas that originated from the Indigenous communities involved were significantly more associated with achieving meaningful community engagement.

CONCLUSIONS

The reporting of Indigenous community engagement in published arthritis studies is limited in frequency and is most frequently described at the lower end of the community engagement spectrum. Processes that support meaningful community engagement are to be promoted.

Inflammatory Arthritis Prevalence and Health Services Use in the First Nations and Non-First Nations Populations of Alberta, Canada

OBJECTIVE

To estimate prevalence of rheumatoid arthritis (RA), ankylosing spondylitis (AS), psoriatic disease (PsD), and crystal-related arthritis and health care use for inflammatory arthritis in First Nations and non-First Nations patients in Alberta, Canada.

METHODS

Population-based cohorts of adults with RA, AS, PsD, and crystal-related arthritis were defined, with First Nations determination by premium payer status, to estimate prevalence rates. Rates of outpatient primary care, specialist visits, and hospitalizations (all-cause, inflammatory-arthritis specific) were estimated.

RESULTS

RA affected 3 times as many First Nations residents compared to non-First Nations residents (standardized rate ratio [SRR] 3.2, 95% confidence interval [95% CI] 2.9-3.4). AS and PsD were more prevalent in First Nations (AS 0.6 per 100 residents; SRR 2.7, 95% CI 2.3-3.2 and PsD 0.3 per 100 residents; SRR 1.5, 95% CI 1.3-1.9), whereas crystal-related arthritis was less prevalent (SRR 0.7, 95% CI 0.6-0.7). First Nations patients were more likely to have primary care visits (SRR 1.7, 95% CI 1.6-1.8) and less likely to have specialist visits (SRR 0.6, 95% CI 0.6-0.7) for RA relative to non-First Nations individuals. In PsD and crystal-related arthritis, First Nations people had higher rates of cause-specific hospitalizations.

CONCLUSION

The estimated prevalence of RA, AS, and PsD was higher in the First Nations population, while crystal-related arthritis was less prevalent compared to the non-First Nations population. First Nations people were more likely to see primary care physicians and were less likely to see specialists for inflammatory arthritis care.

Survival outcomes of First Nations patients with oral cavity squamous cell carcinoma (Poliquin 2014)

Background

Oral cavity squamous cell carcinoma (OCSCC) is the most common head and neck cancer, affecting approximately 2000 Canadians yearly. Analysis of Canadian Cancer Registry data has shown that the incidence of oral cavity cancer is decreasing and survival outcomes are improving.

There are significant health disparities in First Nations (FN) people in Canada. The incidence of cancer in FN groups is significantly lower when compared to the general population, but the cancer-related morbidity and mortality is significantly higher. There is no Canadian literature currently for OCSCC, or any other head and neck cancer, that compares survival outcomes of FN to the overall population. Therefore, the objective of this study is to determine whether there is a difference in epidemiology and survival outcomes between FN and non-FN patients with OCSCC.

Methods

This is a retrospective study of a population-based, prospectively-collected database from Alberta Cancer Registry (ACR). Patients with OCSCC, diagnosed and treated in Alberta between 1998 and 2009 were included. ACR data collected included patient gender, age at diagnosis, tobacco and alcohol use, FN status, TNM staging, performance status, date of death, cause of death, and follow-up. FN status was identified through the Alberta Health and Wellness registry and through postal code correlation for those who live on reserves.

Results

A total of 583 patients with OCSCC were included in this study. Of these, 19 were identified as being FN, leaving 564 non-FN patients. When comparing the FN and non-FN groups, there is no significant difference in baseline demographics. Estimated yearly incidences for OCSCC in the Alberta population (all ages) and FN patients are 1.74/100,000 and 1.32/100,000 respectively (p = 0.23). Significant differences are seen in overall survival (OS) (5-year OS 58.1% for non-FN and 33.7% for FN) and for disease-specific survival (DSS) (5-year DSS 67.8% for non-FN and 44.5% for FN). Multivariate analysis confirmed FN patients have a significant increase risk of death in OS and DSS, with hazard ratios of 4.20 (p = 0.01) and 4.57 (p = 0.02), respectively.

Conclusions

The overall survival and disease specific survival are significantly lower in FN patients compared to non-FN patients with OCSCC.

Imbalance of Prevalence and Specialty Care for Osteoarthritis for First Nations People in Alberta, Canada

Objective.

To estimate the population-based prevalence and healthcare use for osteoarthritis (OA) by First Nations (FN) and non-First Nations (non-FN) in Alberta, Canada.

Methods.

A cohort of adults with OA (≥ 2 physician claims in 2 yrs or 1 hospitalization with ICD-9-Clinical Modification code 715x or ICD-10-Canadian Adaptation code M15-19, 1993–2010) was defined with FN determination by premium payer status. Prevalence rates (2007/8) were estimated from the cohort and the population registered with the Alberta Health Care Insurance Plan. Rates of outpatient primary care and specialist visits (orthopedics, rheumatology, internal medicine), arthroplasty (hip and knee), and all-cause hospitalization were estimated.

Results.

OA prevalence in FN was twice that of the non-FN population [16.1 vs 7.8 cases/100 population, standardized rate ratio (SRR) adjusted for age and sex 2.06, 95% CI 2.00–2.12]. The SRR (adjusted for age, sex, and location of residence) for primary care visits for OA was nearly double in FN compared with non-FN (SRR 1.88, 95% CI 1.87–1.89), and internal medicine visits were increased (SRR 1.25, 95% CI 1.25–1.26). Visit rates with an orthopedic surgeon (SRR 0.49, 95% CI 0.48–0.50) or rheumatologist (SRR 0.62, 95% CI 0.62–0.63) were substantially lower in FN with OA. Hip and knee arthroplasties were performed less frequently in FN with OA (SRR 0.48, 95% CI 0.47–0.49), but all-cause hospitalization rates were higher (SRR 1.59, 95% CI 1.58–1.60).

Conclusion.

We estimate a 2-fold higher prevalence of OA in the FN population with differential healthcare use. Reasons for higher use of primary care and lower use of specialty services and arthroplasty compared with the general population are not yet understood.

Myositis registries and biorepositories: powerful tools to advance clinical, epidemiologic and pathogenic research

PURPOSE OF REVIEW

Clinical registries and biorepositories have proven extremely useful in many studies of diseases, especially rare diseases. Given their rarity and diversity, the idiopathic inflammatory myopathies, or myositis syndromes, have benefited from individual researchers' collections of cohorts of patients. Major efforts are being made to establish large registries and biorepositories that will allow many additional studies to be performed that were not possible before. Here, we describe the registries developed by investigators and patient support groups that are currently available for collaborative research purposes.

RECENT FINDINGS

We have identified 46 myositis research registries, including many with biorepositories, which have been developed for a wide variety of purposes and have resulted in great advances in understanding the range of phenotypes, clinical presentations, risk factors, pathogenic mechanisms, outcome assessment, therapeutic responses, and prognoses. These are now available for collaborative use to undertake additional studies. Two myositis patient registries have been developed for research, and myositis patient support groups maintain demographic registries with large numbers of patients available to be contacted for potential research participation.

SUMMARY

Investigator-initiated myositis research registries and biorepositories have proven extremely useful in understanding many aspects of these rare and diverse autoimmune diseases. These registries and biorepositories, in addition to those developed by myositis patient support groups, deserve continued support to maintain the momentum in this field as they offer major opportunities to improve understanding of the pathogenesis and treatment of these diseases in cost-effective ways.

Epidemiology of idiopathic inflammatory myopathy in Hungary

Introduction: Idiopathic inflammatory myopathy (called also myositis) is a systemic autoimmune disease mainly characterised with proximal muscle weakness. The most frequent subsets are polymyositis and dermatomyositis. The epidemiology of these diseases is not entirely explored. There is a need to build national and international registries which may help to obtain more data. The Myositis Team at the Department of Clinical Immunology, University of Debrecen, has been established in 1975. Aim: The aim of the authors was to obtain epidemiological data on this disease. Method: The authors analysed the database of the National Health Insurance Fund Administration of Hungary which included 1119 patients with myositis, of which 289 patients were followed up by the authors. Results: The average incidence of the disease was found to be 0.95/100.000/year. The male/female ratio was 1/2. Dermatomyositis occurred both in children and adult, but polymyositis was found mainly in adults. These epidemiological data partly correlate with those published in the international literature. Conclusions: The authors propose to establish a National Myositis Registry in the frame of multicentric collaboration in order to have more information about the disease. Orv. Hetil., 2014, 155(41), 1643–1646.

Registries in idiopathic inflammatory myopathies

PURPOSE OF REVIEW

The idiopathic inflammatory myopathies myositis are rare diseases with limited information on risk factors for disease and prognosis. The aim of this review is to give an overview of how registries can be used in myositis research.

RECENT FINDINGS

Population-based registries have been used in a number of incidence and prevalence studies in the review period and have shown myositis to be more common than previously reported. Disease-specific registries have been used for detailed studies on subphenotypes and longitudinal studies to identify prognostic markers and treatment outcomes.

SUMMARY

Registries, both national healthcare and health insurance registries, as well as disease-specific clinical registries, are useful sources to investigate a rare disease like myositis. To achieve increased understanding of whether different subphenotypes differ in treatment outcome and prognosis, a large number of patients need to be followed longitudinally in a systematic way. A novel international, multidisciplinary registry, EUROMYOSITIS, has been developed. This is an open source registry with to date 20 centers and more than 2500 patients with myositis, many of whom are followed longitudinally. This registry has clear potentials for clinical and epidemiological research, as well as for clinical trial in myositis, and welcomes investigators from all over the world.

Validity of myocardial infarction diagnoses in administrative databases: a systematic review

BACKGROUND

Though administrative databases are increasingly being used for research related to myocardial infarction (MI), the validity of MI diagnoses in these databases has never been synthesized on a large scale.

OBJECTIVE

To conduct the first systematic review of studies reporting on the validity of diagnostic codes for identifying MI in administrative data.

METHODS

MEDLINE and EMBASE were searched (inception to November 2010) for studies: (a) Using administrative data to identify MI; or (b) Evaluating the validity of MI codes in administrative data; and (c) Reporting validation statistics (sensitivity, specificity, positive predictive value (PPV), negative predictive value, or Kappa scores) for MI, or data sufficient for their calculation. Additonal articles were located by handsearch (up to February 2011) of original papers. Data were extracted by two independent reviewers; article quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool.

RESULTS

Thirty studies published from 1984-2010 were included; most assessed codes from the International Classification of Diseases (ICD)-9th revision. Sensitivity and specificity of hospitalization data for identifying MI in most [≥50%] studies was ≥86%, and PPV in most studies was ≥93%. The PPV was higher in the more-recent studies, and lower when criteria that do not incorporate cardiac troponin levels (such as the MONICA) were employed as the gold standard. MI as a cause-of-death on death certificates also demonstrated lower accuracy, with maximum PPV of 60% (for definite MI).

CONCLUSIONS

Hospitalization data has higher validity and hence can be used to identify MI, but the accuracy of MI as a cause-of-death on death certificates is suboptimal, and more studies are needed on the validity of ICD-10 codes. When using administrative data for research purposes, authors should recognize these factors and avoid using vital statistics data if hospitalization data is not available to confirm deaths from MI.

Systemic autoimmune rheumatic disease prevalence in Canada: updated analyses across 7 provinces

OBJECTIVE

To estimate systemic autoimmune rheumatic disease (SARD) prevalence across 7 Canadian provinces using population-based administrative data evaluating both regional variations and the effects of age and sex.

METHODS

Using provincial physician billing and hospitalization data, cases of SARD (systemic lupus erythematosus, scleroderma, primary Sjögren syndrome, polymyositis/dermatomyositis) were ascertained. Three case definitions (rheumatology billing, 2-code physician billing, and hospital diagnosis) were combined to derive a SARD prevalence estimate for each province, categorized by age, sex, and rural/urban status. A hierarchical Bayesian latent class regression model was fit to account for the imperfect sensitivity and specificity of each case definition. The model also provided sensitivity estimates of different case definition approaches.

RESULTS

Prevalence estimates for overall SARD ranged between 2 and 5 cases per 1000 residents across provinces. Similar demographic trends were evident across provinces, with greater prevalence in women and in persons over 45 years old. SARD prevalence in women over 45 was close to 1%. Overall sensitivity was poor, but estimates for each of the 3 case definitions improved within older populations and were slightly higher for men compared to women.

CONCLUSION

Our results are consistent with previous estimates and other North American findings, and provide results from coast to coast, as well as useful information about the degree of regional and demographic variations that can be seen within a single country. Our work demonstrates the usefulness of using multiple data sources, adjusting for the error in each, and providing estimates of the sensitivity of different case definition approaches.