Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Susan G. Barr is active.

Publication


Featured researches published by Susan G. Barr.


Journal of Autoimmunity | 2013

Cancer risk in systemic lupus: An updated international multi-centre cohort study

Sasha Bernatsky; Rosalind Ramsey-Goldman; Jeremy Labrecque; Lawrence Joseph; Jean François Boivin; Michelle Petri; Asad Zoma; Susan Manzi; Murray B. Urowitz; Dafna D. Gladman; Paul R. Fortin; Ellen M. Ginzler; Edward H. Yelin; Sang-Cheol Bae; Daniel J. Wallace; Steven M. Edworthy; Søren Jacobsen; Caroline Gordon; Mary Anne Dooley; Christine A. Peschken; John G. Hanly; Graciela S. Alarcón; Ola Nived; Guillermo Ruiz-Irastorza; David A. Isenberg; Anisur Rahman; Torsten Witte; Cynthia Aranow; Diane L. Kamen; Kristjan Steinsson

OBJECTIVE To update estimates of cancer risk in SLE relative to the general population. METHODS A multisite international SLE cohort was linked with regional tumor registries. Standardized incidence ratios (SIRs) were calculated as the ratio of observed to expected cancers. RESULTS Across 30 centres, 16,409 patients were observed for 121,283 (average 7.4) person-years. In total, 644 cancers occurred. Some cancers, notably hematologic malignancies, were substantially increased (SIR 3.02, 95% confidence interval, CI, 2.48, 3.63), particularly non-Hodgkins lymphoma, NHL (SIR 4.39, 95% CI 3.46, 5.49) and leukemia. In addition, increased risks of cancer of the vulva (SIR 3.78, 95% CI 1.52, 7.78), lung (SIR 1.30, 95% CI 1.04, 1.60), thyroid (SIR 1.76, 95% CI 1.13, 2.61) and possibly liver (SIR 1.87, 95% CI 0.97, 3.27) were suggested. However, a decreased risk was estimated for breast (SIR 0.73, 95% CI 0.61-0.88), endometrial (SIR 0.44, 95% CI 0.23-0.77), and possibly ovarian cancers (0.64, 95% CI 0.34-1.10). The variability of comparative rates across different cancers meant that only a small increased risk was estimated across all cancers (SIR 1.14, 95% CI 1.05, 1.23). CONCLUSION These data estimate only a small increased risk in SLE (versus the general population) for cancer over-all. However, there is clearly an increased risk of NHL, and cancers of the vulva, lung, thyroid, and possibly liver. It remains unclear to what extent the association with NHL is mediated by innate versus exogenous factors. Similarly, the etiology of the decreased breast, endometrial, and possibly ovarian cancer risk is uncertain, though investigations are ongoing.


Arthritis Care and Research | 1999

Quality of life in systemic lupus erythematosus patients during more and less active disease states: Differential contributors to mental and physical health

Patricia L. Dobkin; Deborah Da Costa; Maria Dritsa; Paul R. Fortin; Jean-Luc Senécal; Jean-Richard Goulet; D. Choquette; Eric Rich; André D. Beaulieu; Alfred Cividino; Steven M. Edworthy; Susan G. Barr; Stephanie Ensworth; John M. Esdaile; Dafna D. Gladman; Doug Smith; Michael Zummer; Ann E. Clarke

OBJECTIVE To identify determinants of mental and physical health as a function of disease state in patients with systemic lupus erythematosus (SLE). METHODS A sample of 129 SLE patients (mean age 42.01 years; SD 11.09) was recruited from 9 immunology/rheumatology clinics across Canada. Patients completed questionnaires assessing psychological distress, social support, coping, stress, and health-related quality of life. Physicians rated disease activity (using the revised Systemic Lupus Activity Measure; SLAM-R) and damage (using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index). Mental and physical health composite scores were derived from the Medical Outcomes Study Short Form 36. Patients were subdivided into more active (SLAM-R > or = 10; n = 38) or less active disease states (n = 91). RESULTS Better mental health was predicted by more education and less emotion-oriented coping in the patients in a more active disease state (P = 0.0001; R2 = 0.46). Better mental health was predicted by less stress, less emotion-oriented coping and more task-oriented coping in patients during a less active disease state (P = 0.0001; R2 = 0.45). Better physical health was predicted by more emotion-oriented coping in patients in a more active disease state (P = 0.04; R2 = 0.11). Better physical health was predicted by less stress and younger age in patients during a less active disease state (P = 0.0001; R2 = 0.20). CONCLUSION The positive association between emotion-oriented coping and better physical health in patients during a more active disease state suggests that this style of coping may be more adaptive in situations that are considered uncontrollable (e.g., SLE flare). Predictors of mental health were similar to those found in the literature, especially for SLE patients in a less active disease state.


Arthritis Research & Therapy | 2003

The use and abuse of commercial kits used to detect autoantibodies

Marvin J. Fritzler; Allan Wiik; Mark L. Fritzler; Susan G. Barr

The detection of autoantibodies in human sera is an important approach to the diagnosis and management of patients with autoimmune conditions. To meet market demands, manufacturers have developed a wide variety of easy to use and cost-effective diagnostic kits that are designed to detect a variety of human serum autoantibodies. A number of studies over the past two decades have suggested that there are limitations and concerns in the use and clinical application of test results derived from commercial kits. It is important to appreciate that there is a complex chain of users and circumstances that contributes to variations in the apparent reliability of commercial kits. The goal of this review is to identify the principal links in this chain, to identify the factors that weaken the chain and to propose a plan of resolution. It is suggested that a higher level of commitment and partnership between all of the participants is required to achieve the goal of improving the quality of patient care through the use of autoantibody testing and analysis.


Annals of the Rheumatic Diseases | 2014

Lymphoma risk in systemic lupus: effects of disease activity versus treatment

Sasha Bernatsky; Rosalind Ramsey-Goldman; Lawrence Joseph; Jean François Boivin; Karen H. Costenbader; Murray B. Urowitz; Dafna D. Gladman; Paul R. Fortin; Ola Nived; Michelle Petri; Søren Jacobsen; Susan Manzi; Ellen M. Ginzler; David A. Isenberg; Anisur Rahman; Caroline Gordon; Guillermo Ruiz-Irastorza; Edward H. Yelin; Sang-Cheol Bae; Daniel J. Wallace; Christine A. Peschken; Mary Anne Dooley; Steven M. Edworthy; Cynthia Aranow; Diane L. Kamen; Juanita Romero-Diaz; Anca Askanase; Torsten Witte; Susan G. Barr; Lindsey A. Criswell

Objective To examine disease activity versus treatment as lymphoma risk factors in systemic lupus erythematosus (SLE). Methods We performed case–cohort analyses within a multisite SLE cohort. Cancers were ascertained by regional registry linkages. Adjusted HRs for lymphoma were generated in regression models, for time-dependent exposures to immunomodulators (cyclophosphamide, azathioprine, methotrexate, mycophenolate, antimalarial drugs, glucocorticoids) demographics, calendar year, Sjogrens syndrome, SLE duration and disease activity. We used adjusted mean SLE Disease Activity Index scores (SLEDAI-2K) over time, and drugs were treated both categorically (ever/never) and as estimated cumulative doses. Results We studied 75 patients with lymphoma (72 non-Hodgkin, three Hodgkin) and 4961 cancer-free controls. Most lymphomas were of B-cell origin. As is seen in the general population, lymphoma risk in SLE was higher in male than female patients and increased with age. Lymphomas occurred a mean of 12.4 years (median 10.9) after SLE diagnosis. Unadjusted and adjusted analyses failed to show a clear association of disease activity with lymphoma risk. There was a suggestion of greater exposure to cyclophosphamide and to higher cumulative steroids in lymphoma cases than the cancer-free controls. Conclusions In this large SLE sample, there was a suggestion of higher lymphoma risk with exposure to cyclophosphamide and high cumulative steroids. Disease activity itself was not clearly associated with lymphoma risk. Further work will focus on genetic profiles that might interact with medication exposure to influence lymphoma risk in SLE.


Lupus | 2006

Mortality related to cerebrovascular disease in systemic lupus erythematosus

Sasha Bernatsky; Ann E. Clarke; Dafna D. Gladman; Murray B. Urowitz; Paul R. Fortin; Susan G. Barr; J. L. Senécal; Michel Zummer; Steven M. Edworthy; John Sibley; Janet E. Pope; Stephanie Ensworth; Rosalind Ramsey-Goldman; John G. Hanly

The objective of this study was to examine mortality rates related to cerebrovascular disease in systemic lupus erythematosus (SLE) compared to the general population. Our sample was a multisite Canadian SLE cohort (10 centres, n = 2688 patients). Deaths due to cerebrovascular disease were ascertained by vital statistics registry linkage using ICD diagnostic codes. Standardized mortality ratio (SMR, ratio of deaths observed to expected) estimates were calculated. The total SMR for death due to cerebrovascular disease was 2.0 (95% confidence interval [CI] 1.0, 3.7). When considering specific types of events, the category with the greatest increased risk was that of ill-defined cerebrovascular events (SMR 44.9, 95% CI 9.3, 131.3) and other cerebrovascular disease (SMR 8.4, 95% CI 2.3, 21.6). Deaths due to cerebral infarctions appeared to be less common than hemorrhages and other types of cerebrovascular events. Our data suggest an increase in mortality related to cerebrovascular disease in SLE patients compared to the general population. The large increase in illdefined cerebrovascular events may represent cases of cerebral vasculitis or other rare forms of nervous system disease; alternately, it may reflect diagnostic uncertainty regarding the etiology of some clinical presentations in SLE patients. The suggestion that more deaths are attributed to cerebral hemorrhage, as opposed to infarction, indicates that inherent or iatrogenic factors (eg, thrombocytopenia or anticoagulation) may be important. In view of the paucity of large-scale studies of mortality attributed to neuropsychiatric outcomes in SLE, our findings highlight the need for additional research in large SLE cohorts.


Annals of Behavioral Medicine | 2002

Counterbalancing Patient Demands With Evidence: Results From a Pan-Canadian Randomized Clinical Trial of Brief Supportive-Expressive Group Psychotherapy for Women With Systemic Lupus Erythematosus

Patricia L. Dobkin; Deborah Da Costa; Lawrence Joseph; Paul R. Fortin; Steven M. Edworthy; Susan G. Barr; Stephanie Ensworth; John M. Esdaile; André D. Beaulieu; Michel Zummer; Jean-Luc Sené cal; Jean-Richard Goulet; D. Choquette; Eric Rich; Doug Smith; Alfred Cividino; Dafna D. Gladman; Yvan St-Pierre; Ann E. Clarke

Objective: To evaluate the effect of Brief Supportive-Expressive Group Psychotherapy as an adjunct to standard medical care in reducing psychological distress, medical symptoms, and health care costs and improving quality of life in women with systemic lupus erythematosus (SLE). Methods: A randomized clinical trial was conducted with 133 SLE female patients from 9 clinics across Canada. Clinical and psychosocial measures were taken at baseline, posttreatment, and 6 and 12 months posttreatment. Outcomes assessed were psychological distress, quality of life, disease activity, health service utilization, and diminished productivity. Results: Intention-to-treat analyses revealed that there were no clinically important group differences on any of the outcome measures. Conclusion: Although both groups improved over time on several measures (e.g., decreases in psychological distress, stress, and emotion-oriented coping), these changes could not be attributed to the psychotherapeutic intervention. Thus, evidence does not support the referral of these patients to this type of intervention.


Genes and Immunity | 2011

A targeted association study in systemic lupus erythematosus identifies multiple susceptibility alleles

M L Budarf; Philippe Goyette; Gabrielle Boucher; J Lian; Robert R. Graham; Jaime O. Claudio; Thomas J. Hudson; Dafna D. Gladman; Ann E. Clarke; Janet E. Pope; Christine A. Peschken; C. D. Smith; John G. Hanly; Eric Rich; Gilles Boire; Susan G. Barr; Michel Zummer; Paul R. Fortin; Joan Wither; John D. Rioux

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease. Multiple genetic and environmental factors contribute to the pathogenesis of this disease. Recent genome-wide association studies have added substantially to the number of genes associated with SLE. To replicate some of these susceptibility loci, single-nucleotide polymorphisms reported to be associated to SLE were evaluated in a cohort of 245 well-phenotyped Canadian SLE trios. Our results replicate previously reported associations to alleles of interferon regulatory factor 5 (IRF5), major histocompatibility complex (MHC), tumor necrosis factor (ligand) superfamily member 4 (TNFSF4), Kell blood group complex subunit-related family member 6 (XKR6), B-cell scaffold protein with ankyrin repeats 1 (BANK1), protein tyrosine phosphatase non-receptor type 22 (PTPN22), ubiquitin-conjugating enzyme E2L 3 (UBE2L3) and islet cell autoantigen 1 (ICA1). We also identify putative associations to cytotoxic T-lymphocyte-associated protein 4 (CTLA4), a gene associated with several autoimmune disorders, and ERBB3, a locus on 12q13 that was previously reported to be associated with type 1 diabetes. This study confirms the existence of multiple genetic risk factors for SLE, and supports the notion that some risk factors for SLE are shared with other inflammatory disorders.


PLOS ONE | 2014

Clinical and Serological Features of Patients Referred through a Rheumatology Triage System because of Positive Antinuclear Antibodies

Christie Fitch-Rogalsky; Whitney Steber; Michael Mahler; Terri Lupton; Liam Martin; Susan G. Barr; Dianne Mosher; James Wick; Marvin J. Fritzler

Background The referral of patients with positive anti-nuclear antibody (ANA) tests has been criticized as an inappropriate use of medical resources. The utility of a positive ANA test in a central triage (CT) system was studied by determining the autoantibody profiles and clinical diagnoses of patients referred to rheumatologists through a CT system because of a positive ANA test. Methods Patients that met three criteria were included: (1) referred to Rheumatology CT over a three year interval; (2) reason for referral was a “positive ANA”; (3) were evaluated by a certified rheumatologist. The CT clinical database was used to obtain demographic and clinical information and a serological database was used to retrieve specific ANA and/or extractable nuclear antigen (ENA) test results. Clinical information was extracted from the consulting rheumatologists report. Results 15,357 patients were referred through the CT system; 643 (4.1%) of these because of a positive ANA and of these 263 (40.9%) were evaluated by a certified rheumatologist. In 63/263 (24%) of ANA positive patients, the specialist provided a diagnosis of an ANA associated rheumatic disease (AARD) while 69 (26.2%) had no evidence of any disease; 102 (38.8%) had other rheumatologic diagnoses and 29 (11%) had conditions that did not meet AARD classification criteria. Of ANA positive archived sera, 15.1% were anti-DFS70 positive and 91.2% of these did not have an AARD. Conclusions This is the first study to evaluate the serological and clinical features of patients referred through a CT system because of a positive ANA. The spectrum of autoantibody specificities was wide with anti-Ro52/TRIM21 being the most common autoantibody detected. Approximately 15% of referrals had only antibodies to DFS70, the vast majority of which did not have clinical evidence for an AARD. These findings provide insight into the utility of autoantibody testing in a CT system.


Nature Reviews Rheumatology | 2016

The global burden of SLE: prevalence, health disparities and socioeconomic impact

Erin E. Carter; Susan G. Barr; Ann E. Clarke

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease that can potentially lead to serious organ complications and even death. Its global burden — in terms of incidence and prevalence, differential impact on populations, economic costs and capacity to compromise health-related quality of life — remains incompletely understood. The reported worldwide incidence and prevalence of SLE vary considerably; this variation is probably attributable to a variety of factors, including ethnic and geographic differences in the populations being studied, the definition of SLE applied, and the methods of case identification. Despite the heterogeneous nature of the disease, distinct patterns of disease presentation, severity and course can often be related to differences in ethnicity, income level, education, health insurance status, level of social support and medication compliance, as well as environmental and occupational factors. Given the potential for the disease to cause such severe and widespread organ damage, not only are the attendant direct costs high, but these costs are sometimes exceeded by indirect costs owing to loss of economic productivity. As an intangible cost, patients with SLE are, not surprisingly, likely to endure considerably reduced health-related quality of life.


Arthritis Care and Research | 2012

Prevalence of systemic lupus erythematosus and systemic sclerosis in the First Nations population of Alberta, Canada

Cheryl Barnabe; Lawrence Joseph; Patrick Bélisle; Jeremy Labrecque; Steven M. Edworthy; Susan G. Barr; Marvin J. Fritzler; Lawrence W. Svenson; Brenda R. Hemmelgarn; Sasha Bernatsky

To estimate the population‐based prevalence of systemic lupus erythematosus (SLE) and systemic sclerosis (SSc) in Alberta, Canada, stratified by First Nations status.

Collaboration


Dive into the Susan G. Barr's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Sasha Bernatsky

McGill University Health Centre

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Susan Manzi

Allegheny Health Network

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Ellen M. Ginzler

SUNY Downstate Medical Center

View shared research outputs
Researchain Logo
Decentralizing Knowledge