When Should I Get My Next COVID-19 Vaccine? Data From the Surveillance of Responses to COVID-19 Vaccines in Systemic Immune-Mediated Inflammatory Diseases (SUCCEED) Study.

OBJECTIVE: To determine how serologic responses to coronavirus disease 2019 (COVID-19) vaccination and infection in immune-mediated inflammatory disease (IMID) are affected by time since last vaccination and other factors. METHODS: Post-COVID-19 vaccination, data, and dried blood spots or sera were collected from adults with rheumatoid arthritis, inflammatory bowel disease, systemic lupus erythematosus, ankylosing spondylitis and spondylarthritis, and psoriasis and psoriatic arthritis. The first sample was collected at enrollment, then at 2 to 4 weeks and 3, 6, and 12 months after the latest vaccine dose. Multivariate generalized estimating equation regressions (including medications, demographics, and vaccination history) evaluated serologic response, based on log-transformed anti-receptor-binding domain (RBD) IgG titers; we also measured antinucleocapsid (anti-N) IgG. RESULTS: Positive associations for log-transformed anti-RBD titers were seen with female sex, number of doses, and self-reported COVID-19 infections in 2021 to 2023. Negative associations were seen with prednisone, anti-tumor necrosis factor agents, and rituximab. Over the 2021-2023 period, most (94%) of anti-N positivity was associated with a self-reported infection in the 3 months prior to testing. From March 2021 to February 2022, anti-N positivity was present in 5% to 15% of samples and was highest in the post-Omicron era, with antinucleocapsid positivity trending to 30% to 35% or higher as of March 2023. Anti-N positivity in IMID remained lower than Canada's general population seroprevalence (> 50% in 2022 and > 75% in 2023). Time since last vaccination was negatively associated with log-transformed anti-RBD titers, particularly after 210 days. CONCLUSION: Ours is the first pan-Canadian IMID assessment of how vaccine history and other factors affect serologic COVID-19 vaccine responses. These findings may help individuals personalize vaccination decisions, including consideration of additional vaccination when > 6 months has elapsed since last COVID-19 vaccination/infection.

Multiple Sclerosis Risk Among Anti-tumor Necrosis Factor Alpha Users: A Methodological Review of Observational Studies Based on Real-world Data.

Epidemiologic studies on the risk of multiple sclerosis (MS) or demyelinating events associated with anti-tumor necrosis factor alpha (TNFα) use among patients with rheumatic diseases or inflammatory bowel diseases have shown conflicting results. Causal directed acyclic graphs (cDAGs) are useful tools for understanding the differing results and identifying the structure of potential contributing biases. Most of the available literature on cDAGs uses language that might be unfamiliar to clinicians. This article demonstrates how cDAGs can be used to determine whether there is a confounder, a mediator or collider-stratification bias and when to adjust for them appropriately. We also use a case study to show how to control for potential biases by drawing a cDAG depicting anti-TNFα use and its potential to contribute to MS onset. Finally, we describe potential biases that might have led to contradictory results in previous studies that examined the effect of anti-TNFα and MS, including confounding, confounding by contraindication, and bias due to measurement error. Clinicians and researchers should be cognizant of confounding, confounding by contraindication, and bias due to measurement error when reviewing future studies on the risk of MS or demyelinating events associated with anti-TNFα use. cDAGs are a useful tool for selecting variables and identifying the structure of different biases that can affect the validity of observational studies.

Effect of Immunosuppressive or Immunomodulatory Agents on Severe COVID-19 Outcomes: A Population-Based Cohort Study.

OBJECTIVE: We estimated the association between immunosuppressive and immunomodulatory agent (IIA) exposure and severe COVID-19 outcomes in a population-based cohort study. METHODS: Participants were 18 years or older, tested positive for SARS-CoV-2 between February 6, 2020, and August 15, 2021, and were from administrative health data for the entire province of British Columbia, Canada. IIA use within 3 months prior to positive SARS-CoV-2 test included conventional disease-modifying antirheumatic drugs (antimalarials, methotrexate, leflunomide, sulfasalazine, individually), immunosuppressants (azathioprine, mycophenolate mofetil/mycophenolate sodium [MMF], cyclophosphamide, cyclosporine, individually and collectively), tumor necrosis factor inhibitor (TNFi) biologics (adalimumab, certolizumab, etanercept, golimumab, infliximab, collectively), non-TNFi biologics or targeted synthetic disease-modifying antirheumatic drugs (tsDMARDs) (rituximab separately from abatacept, anakinra, secukinumab, tocilizumab, tofacitinib and ustekinumab collectively), and glucocorticoids. Severe COVID-19 outcomes were hospitalizations for COVID-19, ICU admissions, and deaths within 60 days of a positive test. Exposure score-overlap weighting was used to balance baseline characteristics of participants with IIA use compared with nonuse of that IIA. Logistic regression measured the association between IIA use and severe COVID-19 outcomes. RESULTS: From 147,301 participants, we identified 515 antimalarial, 573 methotrexate, 72 leflunomide, 180 sulfasalazine, 468 immunosuppressant, 378 TNFi biologic, 49 rituximab, 144 other non-TNFi biologic or tsDMARD, and 1348 glucocorticoid prescriptions. Risk of hospitalizations for COVID-19 was significantly greater for MMF (odds ratio [95% CI]): 2.82 [1.81-4.40], all immunosuppressants: 2.08 [1.51-2.87], and glucocorticoids: 1.63 [1.36-1.96], relative to nonuse. Similar outcomes were seen for ICU admission and MMF: 2.52 [1.34-4.74], immunosuppressants: 2.88 [1.73-4.78], and glucocorticoids: 1.86 [1.37-2.54]. Only glucocorticoids use was associated with a significant increase in 60-day mortality: 1.58 [1.21-2.06]. No other IIAs displayed statistically significant associations with severe COVID-19 outcomes. CONCLUSION: Current use of MMF and glucocorticoids were associated with an increased risk of severe COVID-19 outcomes compared with nonuse. These results emphasize the variety of circumstances of patients taking IIAs.

Risk of Multiple Sclerosis Among Users of Antitumor Necrosis Factor α in 4 Canadian Provinces: A Population-Based Study.

BACKGROUND AND OBJECTIVES: Antitumor necrosis factor α (TNFα) agents are a class of biologic drugs used for the treatment of several immune-mediated conditions. An increased risk of multiple sclerosis (MS) with their use has been suggested, but studies have been limited. Relevant population-based epidemiologic data linking anti-TNFα to MS are scarce. The objective was to compare the risk of MS in anti-TNFα users with nonusers among patients with rheumatic disease (RD) or inflammatory bowel disease (IBD). METHODS: A nested case-control study was conducted. Population-based health care-linked databases from 4 Canadian provinces were used. All patients with RD or IBD residing within a participating province between January 2000 and March 2018 were identified by validated case definitions. Any anti-TNFα dispensation in the 2 years before the index date (MS onset) was identified. Incident onset MS cases were ascertained using a validated algorithm. Up to 5 controls were matched to each MS case based on birth year ±3 years, disease duration, and health authority (based on region of residence). Conditional logistic regressions were used to calculate the incidence rate ratio (IRR) after adjusting for potential confounders. A meta-analysis was conducted to provide pooled estimates across provinces using random-effects models. RESULTS: Among 296,918 patients with RD patients, 462 MS cases (80.1% female, mean [SD] age, 47.4 [14.6] years) were matched with 2,296 controls (59.5% female, mean [SD] age, 47.4 [14.5] years). Exposure to anti-TNFα occurred in 18 MS cases and 42 controls. After adjusting for matching variables, sex, and the Charlson Comorbidity Index, the pooled IRR was 2.05 (95% CI, 1.13-3.72). Among 84,458 patients with IBD, 190 MS cases (69.5% female, mean [SD] age, 44.3 [12.3] years) were matched with 943 controls (54.1% female, mean [SD] age, 44.2 [12.2] years). Exposure to anti-TNFα occurred in 23 MS cases and 98 controls. The pooled adjusted IRR was 1.35 (95% CI, 0.70-2.59). DISCUSSION: The use of anti-TNFα was associated with an increased risk of MS compared with nonusers, especially among patients with RD. These findings could help clinicians and patients with RD to make more informed treatment decisions. Further studies are needed to validate these results for patients with IBD.

Increased risk of venous thromboembolism in patients with granulomatosis with polyangiitis: A population-based study.

We assessed the risk and time trends of venous thromboembolism (VTE) including pulmonary embolism (PE) and deep venous thrombosis (DVT) in new granulomatosis with polyangiitis (GPA) cases compared to the general population. Using a population-level database from the entire province of British Columbia, Canada, we conducted a matched cohort study of all patients with incident GPA with up to ten age-, sex-, and entry time-matched individuals randomly selected from the general population. We compared incidence rates of VTE, PE, and DVT between the two groups, and calculated hazard ratios (HR), adjusting for relevant confounders. Among 549 individuals with incident GPA (57.6% female, mean age 55.4 years), the incidence rates for VTE, PE, and DVT were 7.22, 2.73, and 6.32 per 1,000 person-years, respectively; the corresponding rates were 1.36, 0.74, and 0.81 per 1,000 person-years among the 5,490 non-GPA individuals. Compared with the non-GPA cohort, the fully adjusted HRs among GPA patients were 2.90 (95% CI, 1.10-7.64), 4.70 (95% CI, 1.74-12.69), and 1.66 (95% CI, 0.52-5.27) for VTE, PE, and DVT, respectively. The risks of VTE, PE, and DVT were highest during the first year after GPA diagnosis with HR (95% CI) of 11.04 (1.37-88.72), 26.94 (4.56-159.24), and 2.68 (0.23-31.21), respectively. GPA patients are at significantly increased risk of PE, but not DVT. Monitoring for these complications is particularly warranted in this patient population, especially early after diagnosis.

COVID-19 Vaccination Uptake Among Individuals With Immune-mediated Inflammatory Diseases in Ontario, Canada, Between December 2020 and October 2021: A Population-based Analysis.

OBJECTIVE: We assessed coronavirus disease 2019 (COVID-19) vaccine uptake among individuals with immune-mediated inflammatory diseases (IMIDs) and the Ontario general population. METHODS: We studied all residents aged ≥ 16 years who were alive and enrolled in the Ontario Health Insurance Plan as of December 14, 2020, when vaccination commenced (n = 12,435,914). Individuals with rheumatoid arthritis (RA), ankylosing spondylitis (AS), psoriatic arthritis (PsA), psoriasis (PsO), and inflammatory bowel disease (IBD) were identified using established disease-specific case definitions applied to health administrative data. Vaccination status was extracted from the provincial COVaxON registry. Weekly cumulative proportions of first and second doses up until October 3, 2021, were expressed as the vaccinated percentage of each disease group, compared to the general Ontario population, and stratified by age. RESULTS: By October 3, 2021, the cumulative percentage with at least 1 dose was 82.1% for the general population, 88.9% for those with RA, 87.4% for AS, 90.6% for PsA, 87.3% for PsO, and 87.0% for IBD. There was also a higher total cumulative percentage with 2 doses among IMIDs (83.8-88.2%) vs the general population (77.9%). The difference was also evident when stratifying by age. Individuals with IMIDs in the youngest age group initially had earlier uptake than the general population but remain the lowest age group with 2 doses (70.6% in the general population vs. 73.7-79.2% across IMID groups). CONCLUSION: While implementation of COVID-19 vaccination programs has differed globally, these Canadian estimates are the first to reassuringly show higher COVID-19 vaccine uptake among individuals with IMIDs.

Immunosuppression and COVID-19 infection in British Columbia: Protocol for a linkage study of population-based administrative and self-reported survey data.

INTRODUCTION: Cases of the novel coronavirus disease (COVID-19) continue to spread around the world even one year after the declaration of a global pandemic. Those with weakened immune systems, due to immunosuppressive medications or disease, may be at higher risk of COVID-19. This includes individuals with autoimmune diseases, cancer, transplants, and dialysis patients. Assessing the risk and outcomes of COVID-19 in this population has been challenging. While administrative databases provide data with minimal selection and recall bias, clinical and behavioral data is lacking. To address this, we are collecting self-reported survey data from a randomly selected subsample with and without COVID-19, which will be linked to administrative health data, to better quantify the risk of COVID-19 infection associated with immunosuppression. METHODS AND ANALYSIS: Using administrative and laboratory data from British Columbia (BC), Canada, we established a population-based case-control study of all individuals who tested positive for SARS-CoV-2. Each case was matched to 40 randomly selected individuals from two control groups: individuals who tested negative for SARS-CoV-2 (i.e., negative controls) and untested individuals from the general population (i.e., untested controls). We will contact 1000 individuals from each group to complete a survey co-designed with patient partners. A conditional logistic regression model will adjust for potential confounders and effect modifiers. We will examine the odds of COVID-19 infection according to immunosuppressive medication or disease type. To adjust for relevant confounders and effect modifiers not available in administrative data, the survey will include questions on behavioural variables that influence probability of being tested, acquiring COVID-19, and experiencing severe outcomes. ETHICS AND DISSEMINATION: This study has received approval from the University of British Columbia Clinical Research Ethics Board [H20-01914]. Findings will be disseminated through scientific conferences, open access peer-reviewed journals, COVID-19 research repositories and dissemination channels used by our patient partners.

Has the excess risk of acute myocardial infarction in rheumatoid arthritis relative to the general population declined? A population study of trends over time.

OBJECTIVE: To evaluate secular trend in ten-year risk of incident acute myocardial infarction (AMI) in incident rheumatoid arthritis (RA) relative to the general population. METHODS: We conducted a retrospective study of population-based incident RA cohorts with RA incidence from 1997 to 2004 in British Columbia, Canada, with matched general population comparators, using administrative health data. RA and their matched cohorts were divided according to the year of RA incidence, defined according to the first RA visit of the case definition. Incident AMI was defined as the first event occurring within 10 years from RA incidence. Secular trend was assessed using delayed-entry Cox models with an interaction term between the year of RA onset and indicator of RA vs. general population. Linear, quadratic and spline functions of year of RA onset were compared to assess possibility of nonlinear trends. The model with the lowest AIC was selected to interpret the results. Sensitivity analyses were conducted to account for potential effect of unmeasured (e.g. smoking) or partially measured (e.g. obesity) confounders in administrative data, on the interaction term. RESULTS: Overall, 23,237 RA and 46,474 general population controls experienced 1,133 and 1,606 incident AMIs, respectively. A linear Cox model was selected as the model best fitting the AMI events. Overall, RA patients were found to have a 21% higher risk of AMI than the matched general population controls [1.21 (1.10, 1.32); p < 0.001]. A significant linear decline in risk of AMI was observed in RA patients [0.94 (95% CI 0.91, 0.97) p = <0.0001], and in the general population [0.93 (0.91, 0.95); p = <0.0001]. The change in AMI risk over time did not differ in RA compared to the general population [p-value of interaction term=0.49]. Our results remained similar after adjusting for the potential effect of confounders on the interaction term, and no difference in the change in risk of AMI over time was observed between RA and the general population. CONCLUSION: Our findings suggest a decline in 10-year risk of AMI in RA, and in the general population. The decline in the risk of AMI over time did not differ between RA and the general population, such that the excess risk of AMI in RA relative to the general population, has remained the same.

Heart disease and the risk of allopurinol-associated severe cutaneous adverse reactions: a general population-based cohort study.

BACKGROUND: Allopurinol is commonly prescribed for gout, and its clinical use may expand with ongoing trials assessing its potential cardiorenal benefits. Because heart disease has been suggested to be a risk factor for allopurinol-associated severe cutaneous adverse reactions, we sought to confirm this association in a Canadian general population cohort. METHODS: We used population data from British Columbia, Canada, to identify all incident allopurinol users between 1997 and 2015. We examined the association between heart disease (ischemic heart disease and heart failure) and the risk of hospital admission for severe cutaneous adverse reactions, adjusting for known and purported risk factors. We also evaluated the joint effects of combined clinical and demographic risk factors. RESULTS: Among 130 325 allopurinol initiators, 109 hospital admissions occurred for allopurinol-associated severe cutaneous adverse reactions. The multivariable relative risk among those with heart disease was 1.55 (95% confidence interval 1.01-2.37). Patients with heart disease and chronic kidney disease who were started on an allopurinol dosage of greater than 100 mg/d had an 11-fold higher risk. Allopurinol initiation at a lower dosage among patients with heart disease and chronic kidney disease resulted in a fivefold reduction in risk. Older women with heart disease from regions with large Asian populations had a 23-fold higher risk of allopurinol-associated severe cutaneous adverse reactions than younger men without heart disease from other regions. INTERPRETATION: Heart disease is independently associated with risk of allopurinol-associated severe cutaneous adverse reactions, similar to chronic kidney disease, and low-dosage allopurinol initiation may substantially mitigate this risk. Risk factors for these rare but serious reactions should be considered when initiating allopurinol.

Clinical spectrum and therapeutics in Canadian patients with anti-melanoma differentiation-associated gene 5 (MDA5)-positive dermatomyositis: a case-based review.

The objective of the study was to determine the clinical features and treatment course in Canadian patients with dermatomyositis (DM) associated with the anti-melanoma differentiation-associated gene 5 antibody (MDA5). A retrospective chart review of consecutive patients with anti-MDA5 antibody DM from two Canadian tertiary care centre between 2014 and 2018 was done. Twenty-one consecutive cases of anti-MDA5-positive DM were identified. Median age at diagnosis was 52 years, 71% Asians, predominantly Chinese, and 29% Caucasians. In this case series, all patients had either typical DM rash, or vasculopathy and ulceration unique to anti-MDA5-positive DM. 38% of the patients had rapid progressive (RP)-interstitial lung disease (RP-ILD), 33% had chronic ILD and 29% had asymptomatic ILD. Anti-Ro52 positivity was more prevalent in RP-ILD. Mortality was high in the RP-ILD group, with five deaths in eight patients. Lung transplant was life-saving intervention for three of the RP-ILD patients who survived. A review of the literature in treating RP-ILD associated with anti-MDA5 is presented. Although evidence is limited to small case series, cyclophosphamide (CYC) for refractory skin lesions, and CYC or mycophenolate mofetil plus a calcineurin inhibitor or rituximab (RTX) for RP-ILD appear efficacious. This is the largest North American case series of anti-MDA5-positive DM patients to date. There is a wide spectrum of clinical presentation of this entity. Survival is poor in those with RP-ILD; early aggressive immunosuppression and timely lung transplant were life-saving in our patients with RP-ILD.

Risk of Incident Chronic Obstructive Pulmonary Disease in Rheumatoid Arthritis: A Population-Based Cohort Study.

OBJECTIVE: Studies have demonstrated a link between chronic obstructive pulmonary disease (COPD) and inflammation, raising the question whether chronic inflammatory conditions, such as rheumatoid arthritis (RA), predispose to COPD. Our objective was to evaluate the risk of incident COPD hospitalization in RA compared to the general population. METHODS: We studied a population-based incident RA cohort with matched general population controls, using administrative health data. All incident RA cases in British Columbia who first met RA definition between January 1996 and December 2006 were selected using previously published criteria. General population controls were randomly selected, matched 1:1 to RA cases on birth year, sex, and index year. COPD outcome was defined as hospitalization with a primary COPD code. Incidence rates, 95% confidence intervals (95% CIs), and incidence rate ratios (IRRs) were calculated for RA and controls. Multivariable Cox proportional hazards models estimated the risk of COPD in RA compared to the general population after adjusting for potential confounders. Sensitivity analyses were performed to test the robustness of the results to the possible confounding effect of smoking, unavailable in administrative data, and to COPD outcome definitions. RESULTS: The cohorts included 24,625 RA individuals and 25,396 controls. The incidence of COPD hospitalization was greater in RA than controls (IRR 1.58, 95% CI 1.34-1.87). After adjusting for potential confounders, RA cases had a 47% greater risk of COPD hospitalization than controls. The increased risk remained significant after modeling for smoking and with varying COPD definitions. CONCLUSION: In our population-based cohort, individuals with RA had a 47% greater risk of COPD hospitalization compared to the general population.

All-Cause and Cause-Specific Mortality in Patients With Granulomatosis With Polyangiitis: A Population-Based Study.

OBJECTIVE: To investigate all-cause and cause-specific mortality in patients with newly diagnosed granulomatosis with polyangiitis (GPA) between 2 calendar time periods, 1997-2004 and 2005-2012. METHODS: Using an administrative health database, we compared all patients with incident GPA with non-GPA controls matched for sex, age, and time of entry into the study. The study cohorts were divided into 2 subgroups based on the year of diagnosis ("early cohort [1997-2004] and "late cohort" [2005-2012]). The outcome was death (all-cause, cardiovascular disease [CVD]-related cancer-related, renal disease-related, and infection-related) during the follow-up period. Hazard ratios (HR) were estimated using Cox proportional hazards models, first adjusted for age, sex, and time of entry and then adjusted for selected covariates based on a purposeful selection algorithm. RESULTS: Three hundred seventy patients with GPA and 3,700 non-GPA controls were included in this study, contributing 1,624.8 and 1,8671.3 person-years of follow-up, respectively. Sixty-eight deaths occurred in the GPA cohort, and 310 deaths occurred in the non-GPA cohort. Overall, the age-, sex-, and entry time-adjusted all-cause mortality HR in the GPA cohort was 3.12 (95% confidence interval CI 2.35-4.14). There was excess mortality due to CVD-related causes, but not cancer, in the GPA cohort. Reports of death due to infection or renal disease was not permitted, because the numbers of death were insufficient (<6 deaths for each outcome). All-cause mortality significantly improved between the early cohort and late cohort time periods (HR 5.61 and 2.33, respectively; P for interaction = 0.017). CONCLUSION: This population-based study showed increased all-cause and CVD-related mortality risks in patients with GPA. There was significant improvement in the all-cause mortality risk over time, but the risk remained increased compared with that in the general population.

Cardiovascular Disease Prevention in Rheumatoid Arthritis: Compliance with Diabetes Screening Guidelines.

OBJECTIVE: To evaluate compliance with diabetes screening guidelines for cardiovascular disease (CVD) prevention in rheumatoid arthritis (RA) compared to the general population. METHODS: We conducted the first longitudinal study of a population-based RA cohort including all prevalent RA cases in British Columbia between 1996 and 2006 and followed until 2010, with matched general population comparators. Using administrative data, we measured compliance with general population guidelines [i.e., testing plasma glucose (PG) at least once every 3 years after age 45] after excluding individuals with previous diabetes. Followup was divided into 3-year eligibility periods. Compliance was measured as the proportion of periods with ≥ 1 PG test performed. OR (95% CI) of compliance in RA (vs general population) was calculated using generalized estimating equation models, adjusting for age and sex. Mean compliance rate per patient was also calculated and compared using the Mann-Whitney U test. RESULTS: Analysis included 22,624 individuals with RA, contributing 48,724 three-year eligibility periods; and 22,579 people in a general population group, contributing 51,081 three-year eligibility periods. PG was measured in 72.3% (SD 37%) of the eligible time periods in the RA sample and in 70.4% (SD 38%) for the general population (OR 1.05, 95% CI 1.02-1.09, p < 0.0001). RA individuals met recommended screening guidelines in 71.4% of their eligible periods, compared to 70.6% (p < 0.001). Screening improved over time in RA relative to the general population. Family physicians ordered nearly all the PG tests. CONCLUSION: Compliance with general population guidelines for diabetes screening in RA was suboptimal, with little difference relative to the general population, despite a higher risk of CVD and diabetes.

Asthma is not associated with the need for surgery in Crohn's disease when controlling for smoking status: a population-based cohort study.

PURPOSE: Growing evidence suggests asthma and Crohn's disease commonly cooccur. However, the impact of asthma on the prognosis of Crohn's disease is unknown. The aim of our study was to assess the effect of asthma on the need for intestinal resection in patients with Crohn's disease while adjusting for smoking status, imputed from a smaller, secondary data set. PATIENTS AND METHODS: Using health administrative data from a universally funded healthcare plan in Alberta, Canada, we conducted a cohort study to assess the effect of asthma on the need for surgery in patients with Crohn's disease diagnosed between 2002 and 2008 (N=2,113). Validated algorithms were used to identify incident cases of Crohn's disease, cooccurring asthma, and intestinal resection. The association between asthma and intestinal resection was estimated using multivariable Cox proportional hazards regression. Smoking status was imputed using a novel method using martingale residuals, derived from a data set of 485 patients enrolled in the Alberta Inflammatory Bowel Disease Consortium (2007 to 2014) who completed environmental questionnaires. All analyses were adjusted for age, sex, rural/urban status, and mean neighborhood income quintile. RESULTS: Asthma did not increase the risk of surgery in the health administrative data when not adjusting for smoking status (HR 1.03, 95% CI 0.81 to 1.29). The association remained nonsignificant after imputing smoking status in the health administrative data (HR 1.03, 95% CI 0.81 to 1.29). CONCLUSION: Although asthma is associated with an increased risk of Crohn's disease, co-occurring asthma is not associated with the risk of surgery in these patients. This null association persisted after adjusting for smoking status. This study described a novel method to adjust for confounding (smoking status) in time-to-event analyses, even when the confounding variable is unmeasured in health administrative data.

Quality of care for cardiovascular disease prevention in rheumatoid arthritis: compliance with hyperlipidemia screening guidelines.

Objective: To evaluate compliance with hyperlipidaemia screening guidelines for cardiovascular disease prevention in RA compared with the general population. Methods: We conducted a longitudinal study of a population-based RA cohort including all prevalent cases in British Columbia between 1996 and 2006, followed up until 2010, with matched general population controls. Using administrative data, we measured compliance with general population guidelines (testing lipids every 5 years for women ⩾50 and men ⩾40), after excluding individuals with previous diabetes, coronary artery disease or hyperlipidaemia. Compliance was measured as the proportion of 5-year eligibility periods with one or more lipid test. Compliance rates in RA and controls were compared by Chi-square test. Odds ratio (95% CI) of compliance in RA (vs controls) was estimated using generalized estimating equation models, adjusting for age and sex. Mean compliance rate per patient was also calculated and compared using Mann-Whitney U test. Results: Analyses included 5587 RA individuals and 5613 controls, contributing 6993 and 7208 5-year eligibility periods, respectively. Lipids were measured in 56.6 and 59.5% of eligibility periods in RA and controls, respectively [adjusted odds ratio (95% CI): 0.97 (0.90, 1.06)]. Screening improved over time in RA relative to the general population, but remained suboptimal even after 2003, at 65.8%. Mean (s.d.) compliance rate per patient was 56.6 (47.2)% for RA and 59.5 (46.6)% for controls. Family physicians ordered almost all the lipid tests. Conclusion: Compliance with general population guidelines for hyperlipidaemia screening in RA was poor and did not differ from the general population, despite a higher risk of cardiovascular diseases.

IL-6 expression is correlated with increased T-cell proliferation and survival in the arterial wall in giant cell arteritis.

Giant cell arteritis (GCA) is the most common vasculitis in adults affecting large and medium-sized arteries. IL-6 and T cell accumulation within the arterial wall contribute to the pathogenesis of GCA, and blockade of IL-6 activity is efficacious in its treatment. We examined the relationship between levels of IL-6 expression and immunological processes that control the expansion of T cells in GCA-positive temporal artery biopsies. CD4 T cells accumulated in clusters within the media and deep intima of all GCA lesions. There was a significant positive correlation between the expression of IL-6 mRNA and increased frequency of proliferating CD4 T cells. The expansion of T cells can be inhibited by T regs but IL-6 expression was not correlated with differences in T reg accumulation. Increased IL-6 levels were also significantly correlated with lower frequencies of CD4 T cells undergoing apoptotic cell death. In conclusion, IL-6 may contribute to the accumulation of CD4 T cells in GCA by supporting their proliferation and survival within the arterial wall through mechanisms that are independent of effects on local T reg expansion.

Filling the gaps in SARDs research: collection and linkage of administrative health data and self-reported survey data for a general population-based cohort of individuals with and without diagnoses of systemic autoimmune rheumatic disease (SARDs) from British Columbia, Canada.

PURPOSE: Systemic autoimmune rheumatic diseases (SARDs) are a group of debilitating autoimmune diseases, including systemic lupus erythematosus and related disorders. Assessing the healthcare and economic burden of SARDs has been challenging: while administrative databases can be used to determine healthcare utilisation and costs with minimal selection and recall bias, other health, sociodemographic and economic data have typically been sourced from highly selected, clinic-based cohorts. To address these gaps, we are collecting self-reported survey data from a general population-based cohort of individuals with and without SARDs and linking it to their longitudinal administrative health data. PARTICIPANTS: Using administrative data from the province of British Columbia (BC), Canada, we established a population-based cohort of all BC adults receiving care for SARDs during 1996-2010 (n=20 729) and non-SARD individuals randomly selected from the general population. BC Ministry of Health granted us contact information for 12 000 SARD and non-SARD individuals, who were recruited to complete the surveys by mail or online. FINDINGS TO DATE: Four hundred individuals were initially invited to participate, with 135 (34%) consenting and 127 (94%) submitting the first survey (72% completed online). Sixty-three (49.6%) reported ≥1 SARD diagnosis. The non-SARDs group (n=64) was 92% female with mean age 57.0±11.6 years. The SARDs group (n=63) was 94% female with mean age 56.5±13.1 years. Forty-eight per cent of those with SARDs were current-or-former smokers (mean 10.6±16.2 pack-years), and 33% were overweight or obese (mean body mass index of 24.4±5.3). FUTURE PLANS: Health and productivity data collected from the surveys will be linked to participants' administrative health data from the years 1990-2013, allowing us to determine the healthcare and lost productivity costs of SARDs, and assess the impact of patient-reported variables on utilisation, costs, disability and clinical outcomes. Findings will be disseminated through scientific conferences and peer-reviewed journals.

Mortality in ANCA-associated vasculitis: ameta-analysis of observational studies.

OBJECTIVE: To determine the magnitude of all-cause mortality risk in patients with antineutrophil cytoplasmic antibodies-associated vasculitis (AAV) compared with the general population through a meta-analysis of observational studies. METHODS: We searched Medline and Embase databases from their inception to April 2015. Observational studies that met the following criteria were assessed by two researchers: (1) clearly defined AAV identified by either the American College of Rheumatology 1990 classification criteria or the 2012 Chapel Hill Consensus Conference disease definitions, and (2) reported standardised mortality ratios (SMR) and 95% CI. We calculated weighted-pooled summary estimates of SMRs (meta-SMRs) for all-cause mortality using random-effects model, tested for publication bias and heterogeneity. RESULTS: Ten studies met the inclusion criteria, comprising 3338 patients with AAV enrolled from 1966 to 2009, and a total of 1091 observed deaths. Overall, we found a 2.7-fold increased risk of death in patients with AAV when compared with the general population (meta-SMR: 2.71 (95% CI 2.26 to 3.24)). Analysis on studies that included only granulomatosis with polyangiitis cases also indicated a similar mortality risk (meta-SMR: 2.63 (95% CI 2.02 to 3.43)). There was no significant publication bias or small-study effect. Subgroup analyses showed that mortality risks were higher in older cohorts, with a trend towards improvement over time (ie, those with their midpoint of enrolment periods that were between 1980-1993 and 1994-1999, vs 2000-2005). CONCLUSION: Published data indicate there is a 2.7-fold increase in mortality among patients with AAV compared with the general population.

Asthma Is Associated With Subsequent Development of Inflammatory Bowel Disease: A Population-based Case-Control Study.

BACKGROUND & AIMS: Asthma and the inflammatory bowel diseases (IBD) each arise through complex interactions between genetic and environmental factors, and share many environmental risk factors. We examined the association between asthma and Crohn's disease or ulcerative colitis. METHODS: We performed a population-based case-control study using health administrative data from the province of Alberta, Canada. The odds of a diagnosis of asthma preceding the diagnosis of either Crohn's disease (N = 3087) or ulcerative colitis (N = 2377) were compared with the odds of diagnosis of asthma among persons without IBD (N = 402,800) using logistic regression. Effect measure modification by age at diagnosis of IBD (16 years or less, 17-40 years, or older than 40 years) was tested using a likelihood ratio test. RESULTS: A diagnosis of asthma was associated with increased odds of incident Crohn's disease (adjusted odds ratio [OR], 1.45; 95% confidence interval [CI], 1.31-1.60). No effect measure modification was observed for age at diagnosis for Crohn's disease (P = .42). However, we observed effect measure modification by age at diagnosis for ulcerative colitis (P = .0103), with an adjusted OR of 1.49 (95% CI, 1.08-2.07) among individuals diagnosed at an age of 16 years or less (OR) and an adjusted OR of 1.57 (95% CI, 1.31-1.89) among individuals diagnosed at an age older than 40 years. However, there was no association between asthma and ulcerative colitis among individuals diagnosed between ages 17 and 40 (adjusted OR, 1.05; 95% CI, 0.86-1.26). CONCLUSIONS: In a population-based case-control study, we associated asthma with Crohn's disease, and with early and late-onset ulcerative colitis.