Crowson, Cynthia S.

ObjectiveRheumatoid arthritis (RA) is postulated to originate at mucosal surfaces, particularly the airway mucosa. To investigate this hypothesis, we determined the association between RA and asthma, passive smoke exposure, and age at start of smoking.MethodsFor this case–control study, we identified 1,023 cases of RA (175 incident) within a single‐center biobank population, using a rules‐based algorithm that combined self‐report with 2 diagnostic codes. Exposures were self‐reported on biobank questionnaires. Logistic regression models were used to calculate the association of exposures with RA, adjusting for potential confounders. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were calculated.ResultsAfter adjustment for allergies, urban environment, and passive smoke exposure, asthma was found to be associated with RA in the full cohort (OR 1.28 [95% CI 1.04–1.58; P = 0.02]) but not the incident RA cohort (OR 1.17 [95% CI 0.66–2.06; P = 0.60]). History of allergic disease was associated with RA in both the full cohort (OR 1.30 [95% CI 1.12–1.51; P < 0.001]) and the incident RA cohort (OR 1.61 [95% CI 1.11–2.33; P = 0.01]), especially food allergy, which was significantly associated with RA in the full cohort (OR 1.38 [95% CI 1.08–1.75; P = 0.01]) and showed a trend toward significance in the incident RA cohort (OR 1.83 [95% CI 0.97–3.45; P = 0.06]). Passive smoke exposure at home or work was not associated with RA. Finally, age at start of smoking was not associated with increased odds of developing RA in either the full cohort (OR 1.03 [95% CI 1.00–1.06; P = 0.03]) or the incident RA cohort (OR 1.00 [95% CI 0.92–1.08; P = 0.98]).ConclusionAsthma and allergies may be associated with increased risk of RA. Passive smoke exposure and early age at start of smoking do not appear to influence risk of RA.

Abstract Erdheim-Chester disease (ECD) is a rare histiocytosis of the “L” (Langerhans) group with multisystem involvement that can affect the large and medium-sized arteries mimicking vasculitis. Aortic involvement is common but the frequency and outcome of aortic branch vessel abnormalities are less well described. Patients with ECD were retrospectively identified. Images containing information of arterial involvement within 6 months of diagnosis were considered baseline and compared to last follow-up studies. Two physicians independently reviewed the studies to evaluate for presence of abnormalities attributable to ECD. Age and sex-adjusted logistic regression models were used to examine associations between patient characteristics and vessel involvement at baseline. Among a cohort of 64 patients with ECD, 63 had baseline imaging of vascular structures. ECD involvement of at least 1 segment of the aorta was observed in 56%. Abnormalities were also observed in aortic arch branches (26%), visceral branch arteries (40%), iliofemoral arteries (31%), coronary (5%), and pulmonary (3%) arteries. Perinephric fibrosis was strongly associated with the identification of abnormalities in the thoracic aorta (OR 4.92 [1.54, 15.75]; P = .007), abdominal aorta (OR 7.57 [2.28, 25.07]; P = .001) and visceral branch arteries (OR 6.05 [1.52, 24.03]; P = .01) but not pelvic/lower extremity arteries. Complete normalization of arterial abnormalities at follow-up was only observed in 9% or less of arterial segments involved at baseline. Aortic and aortic branch vessel abnormalities are frequently observed in patients with ECD and are often asymptomatic. Partial and/or complete resolution of arterial findings is uncommon.

ObjectiveTo identify longitudinal predictors of discordance between patients with rheumatoid arthritis (RA) and their health care providers, where patient global assessment of disease activity is substantially higher than provider global assessment.MethodsThis retrospective case–control study included 102 cases with positive discordance (i.e., ≥25 mm between patient and provider global assessments) and 102 controls without discordance who were matched for age, sex, RA duration, and Clinical Disease Activity Index (CDAI) score. Data were collected at the baseline visit (date of diagnosis or earliest available visit), the index visit (participation in a previous cross‐sectional study), and at up to 11 additional visits before the index visit. Data included patient characteristics, disease activity measures, Disease Activity Score in 28 joints (3‐variable) using the C‐reactive protein level (DAS28‐CRP), and medications. Data were analyzed by using linear and logistic regression models with smoothing splines for nonlinear trends.ResultsOverall, the mean age was 63 years, 75% of patients were female, and the mean RA duration was 10 years. Compared with controls, cases had higher rates of discordant visits during the 4 years before the index visit, and they had a higher CDAI score and DAS28‐CRP earlier in the disease course. Cases more frequently had antinuclear antibodies, nonerosive disease, prior depression, or prior use of antidepressants or fibromyalgia medications. Disease‐modifying medication use was not different between cases and controls.ConclusionThe findings inform new hypotheses about the relationships of disease activity and antinuclear antibodies to the later occurrence of positive discordance among patients with RA.

ObjectiveTo describe the prevalence, clinical presentation, and management of rheumatic immune‐related adverse effects (Rh‐irAEs) from immune checkpoint inhibitor (ICI) therapy.MethodsFrom a database of all patients who received any ICI at the Mayo Clinic Rochester, Minnesota campus between January 1, 2011 and March 1, 2018, we retrospectively identified those with Rh‐irAEs, using diagnostic codes, search terms, and manual chart review.ResultsOf the 1,293 patients who received any ICI, Rh‐irAEs were clinically diagnosed in 43. Eighteen patients with Rh‐irAEs who received ICI therapy elsewhere were also analyzed. Clinical syndromes included inflammatory arthritis (n = 34 [prevalence 2%]), myopathy (n = 10), and other rheumatic syndromes (n = 17). Inflammatory arthritis was most commonly polyarticular, and glucocorticoid treatment was required in 26 patients (76%). The mean ± SD duration of treatment was 18 ± 18 weeks. Five patients (15%) also received disease‐modifying antirheumatic drugs, and ICI therapy had to be discontinued in 3 patients (9%). Myopathy was treated with glucocorticoids in all cases (mean ± SD treatment duration 15 ± 17 weeks) and led to 2 deaths and permanent ICI discontinuation in 9 patients (90%). Other syndromes included connective tissue diseases, vasculitis, polymyalgia rheumatica–like syndrome, and flare of preexisting rheumatic disease. Most (71%) were treated with immunosuppression, with 12% requiring ICI discontinuation.ConclusionThis study represents the largest cohort of patients with Rh‐irAEs reported to date. Most patients received long courses of immunosuppressive treatment, although discontinuation of ICI therapy was required in only a minority.

Abstract Background Antinuclear antibody (ANA)5 testing is routinely performed during evaluation of patients with a suspected connective tissue disease (CTD), yet the question of which method is most appropriate remains controversial. The purpose of this study was to evaluate the clinical utility of ANA testing by an enzyme immunoassay (EIA), an immunofluorescence assay (IFA), and a multiplex immunoassay (MIA) in a routine laboratory population. Methods Samples (n = 1000) were collected from specimens submitted for ANA testing by EIA (Bio-Rad). All samples were subsequently analyzed by IFA (Zeus) and MIA (Bio-Rad). The sample cohort was weighted to represent the routine testing population. Diagnostic information was obtained by chart review. Results For the diagnosis of a CTD, ROC curve analysis demonstrated no significant differences between IFA (area under the curve 0.81) and EIA (0.84) (P = 0.25), with overlay of a single point for the MIA. When normalized to a specificity of approximately 90%, the sensitivities of the MIA, EIA, and IFA were 67%, 67%, and 56%, respectively. By varying the clinical cutoff, the IFA could achieve the highest sensitivity of 94%; however, the corresponding specificity was only 43%. In contrast, a strongly positive EIA had a specificity of 97%, although, at this cutoff, the sensitivity was only 40%. Conclusions Although the overall diagnostic performance of the IFA, EIA, and MIA were not statistically different, the clinical sensitivity and specificity varied dramatically based on the positive/negative cutoff. Knowledge about the performance characteristics of each method will significantly aid in the interpretation of ANA testing.

Abstract Background True population-based clinical and outcomes data are lacking for anti-neutrophil cytoplasmic autoantibody (ANCA)-associated glomerulonephritis (AAGN). Therefore we aimed to estimate the incidence, prevalence and mortality of AAGN, as well as the relationship between the grade of chronic renal damage at presentation and renal and non-renal outcomes. Methods Patients with AAGN were identified among a population-based incident cohort of 57 Olmsted County residents diagnosed with ANCA-associated vasculitis (AAV) in 1996–2015. Incidence rates were age and sex adjusted to the 2010 US white population. Age- and sex-adjusted prevalence was calculated for 1 January 2015. Survival rates were compared with expected rates in the Minnesota population. Chronic renal damage was assessed by chronicity score (CS) on biopsies performed at diagnosis. Results Thirty-four (60%) patients had AAGN. Of these, 65% had microscopic polyangiitis (MPA) and 74% were myeloperoxidase (MPO)-ANCA positive. The annual incidence of AAGN was 2.0/100 000 population [95% confidence interval (CI) 1.3–2.7] and the overall prevalence was 35/100 000 (95% CI 24–47). Mortality for AAGN was increased (P &lt; 0.001), whereas mortality for AAV without glomerulonephritis did not differ from the general population. Minimal to mild CS predicted recovery of renal function at 1 year; clinical diagnosis (granulomatosis with polyangiitis versus MPA) and ANCA specificity (proteinase 3 versus MPO) did not. This observation was replicated in an independent cohort of 38 newly diagnosed AAGN patients seen at our centre over the 1999–2014 period. Conclusions The annual incidence and prevalence of AAGN in Minnesota are 2.0/100 000 and 35/100 000, respectively. Mortality is worse compared with AAV patients without glomerulonephritis. More advanced renal damage at diagnosis predicts less renal recovery.

Objective To determine rates and primary discharge diagnoses of hospitalisation in a cohort of patients with incident primary Sjögren’s syndrome (pSS) compared with the general population. Methods This was a retrospective population-based cohort study focused on Olmsted County, Minnesota. The pSS cohort consisted of patients with incident pSS in the 1976–2015 period and was compared with a cohort of individuals without pSS matched 3:1 for age, sex and calendar year, randomly selected from the same population. Hospitalisations in 1995–2016 were examined. Discharge diagnoses were categorised using the Clinical Classifications Software for International Classification of Diseases, 9th revision, Clinical Modification. Results A total of 385 hospitalisations occurred in the 160 patients with pSS during 1592 person-years of follow-up. Among 466 comparators, there were 899 hospitalisations during 4660 person-years of follow-up, resulting in a significantly higher rate of hospitalisations in patients with pSS (rate ratio (RR): 1.25, 95% CI: 1.11 to 1.41). Rates of hospitalisation were increased among patients with pSS for endocrine, nutritional and metabolic diseases and immunity disorders (RR 1.82, 95% CI 1.08 to 2.98), diseases of the musculoskeletal system and connective tissue (RR 1.49, 95% CI 1.05 to 2.05) and for injuries and poisoning (RR 1.46, 95% CI 1.01 to 2.06). While not significantly increased overall, hospitalisations for diseases of the circulatory system were significantly increased in patients with pSS aged ≥75 years (RR 1.54, 95% CI 1.11 to 2.11). Conclusions Patients with pSS experienced higher rates of hospitalisation than the general population. Hospitalisations for endocrine/metabolic disorders, diseases of the circulatory system, diseases of the musculoskeletal system and connective tissue disorders, and injuries were more common among patients with pSS than comparators.

ObjectiveInflammatory back pain (IBP) is often an early manifestation of spondyloarthritis (SpA), but the prognosis of patients with incident IBP is unknown. This study was undertaken to investigate long‐term outcomes in patients with IBP, and predictors of progression to SpA, in a population‐based cohort.MethodsWe conducted a retrospective, longitudinal study using the Rochester Epidemiology Project, a longstanding population‐based cohort of residents of Olmsted County, MN. Patients ages 16–35 years with clinical visits for back pain from 1999 to 2003 were identified, and we screened these patients for the presence of new‐onset IBP and performed medical record reviews to collect data on clinical, laboratory, and imaging features of SpA. Outcomes in these patients were followed up until July 2016. We used survival analysis for competing risks to examine progression to either SpA, a non‐SpA diagnosis, or resolution of back pain. Recursive partitioning was used to identify predictors of progression to SpA.ResultsAmong 5,304 patients with back pain, we identified 124 patients with new‐onset IBP. After a median follow‐up of 13.2 years, IBP had progressed to SpA in 39 patients, 15 patients developed a non‐SpA diagnosis, and 58 patients had resolution of IBP. At 10 years, the probability of having SpA was 30%, while the probability of resolution of IBP was 43%. The most important predictors for progression to SpA were uveitis, male sex, and family history of SpA.ConclusionIn a minority of patients, new‐onset IBP progresses to SpA, while IBP resolves in many. That IBP often resolves may explain the difference between the prevalence of IBP (3–6%) and the prevalence of SpA (0.4–1.3%).

ObjectiveTo compare patients with large‐vessel giant cell arteritis (LV‐GCA) characterized by wall thickening, stenosis, and/or occlusion of subclavian arteries to those with subclavian dilatation.MethodsFor the purposes of the present retrospective study, 2 different subsets of LV‐GCA were identified and compared from an established cohort of patients with radiographic evidence of subclavian artery vasculitis secondary to GCA: LV‐GCA with wall thickening, stenosis, and/or occlusion of subclavian arteries (Group 1), and LV‐GCA with dilatation of subclavian arteries without wall thickening or stenotic changes (Group 2).ResultsThe study included 109 patients in Group 1 and 11 in Group 2. Large‐vessel involvement secondary to GCA was diagnosed significantly later in patients from Group 2 compared to those from Group 1 (median 15.3 versus 0.0 months; P = 0.010). Compared to patients from Group 1, those from Group 2 were more frequently male (17% versus 45%; P = 0.027), ever smokers (42% versus 73%; P = 0.048), and more frequently had a history of coronary artery disease (11% versus 36%; P = 0.018). At LV‐GCA diagnosis, 10 of the 11 patients (91%) from Group 2 had aortic dilatation compared to 13 of 109 patients (12%) from Group 1 (P < 0.001). During the followup period, the prevalence of aortic aneurysm was significantly higher in patients from Group 2 compared with those from Group 1 (64% versus 7% at 5 years; P < 0.001).ConclusionTwo different subsets of LV‐GCA were identified. Given the strong association between subclavian artery dilatation and aortic aneurysm, such patients should be evaluated and monitored carefully for aortic dilatation.