Objective We describe the demographics, clinical features, disease course, and survival of polyarteritis nodosa (PAN) through an international collaboration (GLOBAL‐PAN). Methods Patients with PAN were recruited between 1990 and 2020 from observational cohorts of nine countries across Europe, Japan, and North America. Eligibility was retrospectively defined using the European Medicines Agency classification algorithm. Patients with PAN related to hepatitis B virus (n = 12) and two monogenic diseases mimicking PAN, deficiency of adenosine deaminase 2 enzyme (n = 16) or familial Mediterranean fever (n = 11), were excluded. Data regarding organ involvement, relapse, disease‐related damage, and survival were analyzed. Results Three hundred fifty‐eight patients (female:male ratio 174:184), including those with systemic PAN (sPAN, n = 282) and cutaneous PAN (n = 76), were included. Twenty‐five were pediatric onset. Mean ± SD age at diagnosis was 44.3 ± 18.1 years. Constitutional symptoms (71.5%), cutaneous involvement (70.5%), musculoskeletal findings (69.1%), and neurologic features (48.0%) were common manifestations. Among patients with sPAN, gastrointestinal involvement and proteinuria over 400 mg/day were reported in 52.2% and 11.2%, respectively. During a median (interquartile range) 59.6 (99.5) months of follow‐up, relapse occurred in 48.5% of patients. One, 5‐ and 10‐year survival rates for sPAN were 97.1%, 94.0%, and 89.0%, respectively. Predictors of death for sPAN included age ≥65 years at diagnosis, serum creatinine at diagnosis >140 μmol/L, gastrointestinal manifestations, and central nervous system (CNS) involvement. Conclusion The spectrum of PAN remains a complex, multifaceted disease. Relapse is common. Age ≥65 years and serum creatinine >140 μmol/L at diagnosis, as well as gastrointestinal and CNS involvement, are independent predictors of death in sPAN. image
Associations between plasma metabolism-associated proteins and future development of giant cell arteritis: results from a prospective study
Abstract Objective The aim of this study was to investigate the relationship between biomarkers associated with metabolism and subsequent development of GCA. Method Participants in the population-based Malmö Diet Cancer Study (MDCS; N = 30 447) who were subsequently diagnosed with GCA were identified in a structured process. Matched GCA-free controls were selected from the study cohort. Baseline plasma samples were analysed using the antibody-based OLINK proteomics metabolism panel (92 metabolic proteins). Analyses were pre-designated as hypothesis-driven or hypothesis-generating. In the latter, principal component analysis was used to identify groups of proteins that explained the variance in the proteome. Results There were 95 cases with a confirmed incident diagnosis of GCA (median 12.0 years after inclusion). Among biomarkers with a priori hypotheses, adhesion G protein-coupled receptor E2 (ADGRE2) was positively associated [odds ratio (OR) per S.D. 1.67; 95% CI 1.08–2.57], and fructose-1,6-bisphosphatase 1 (FBP1) was negatively associated (OR per S.D. 0.59; 95% CI 0.35–0.99) with GCA. In particular, ADGRE2 levels were associated with subsequent GCA in the subset sampled <8.5 years before diagnosis. For meteorin-like protein (Metrnl), the highest impact on the risk of GCA was observed in those patients sampled closest to diagnosis, with a decreasing trend with longer time to GCA (P = 0.03). In the hypothesis-generating analyses, elevated levels of receptor tyrosine-like orphan receptor 1 (ROR1) were associated with subsequent GCA. Conclusion Biomarkers identified years before clinical diagnosis indicated a protective role of gluconeogenesis (FBP1) and an association with macrophage activation (ADGRE2 and Metrnl) and proinflammatory signals (ROR1) for development of GCA.
Analyses of plasma inflammatory proteins reveal biomarkers predictive of subsequent development of giant cell arteritis: a prospective study
Abstract Objective To investigate the relation between biomarkers of inflammation and subsequent development of GCA. Method Participants in the population-based Malmö Diet Cancer Study (MDCS; N = 30 447), established 1991–96, who were subsequently diagnosed with GCA, were identified in a structured process. GCA-free controls, matched for sex, year of birth and year of screening were selected from the study cohort. Baseline plasma samples were analysed using the antibody-based OLINK proteomics inflammation panel (92 inflammatory proteins). Analyses were pre-designated as hypothesis-driven or hypothesis-generating. In the latter, principal component analysis was used to identify groups of proteins that explain the variance in the proteome. Within components selected based on eigenvalues, proteins with a factor loading of >0.50 were investigated. Results Ninety-four cases with a confirmed incident diagnosis of GCA (median 11.9 years after inclusion) were identified. Among biomarkers with a priori hypotheses, IFN-γ was positively associated with GCA [odds ratio (OR) per s.d. 1.52; 95% CI 1.00, 2.30]. Eight biomarkers in the hypothesis-generating analyses were significantly associated with development of GCA. Among these, higher levels of IFN-γ (OR 2.37; 95% CI 1.14, 4.92) and monocyte chemotactic protein 3 (MCP3) (OR 4.27; 95% CI 1.26, 14.53) were particularly associated with increased risk of GCA in the subset sampled <8.5 years before diagnosis. Several other proteins known to be important for T cell function were also associated with GCA in these analyses, e.g. CXCL9, IL-2, CD40 and CCL25. Conclusion Elevated IFN-γ levels were found years prior to diagnosis of GCA. T cell activation may precede the clinical onset of GCA.
Comment on: Negative associations for fasting blood glucose, cholesterol and triglyceride levels with the development of giant cell arteritis: reply
AbstractObjectivesTo investigate metabolic features that may predispose to GCA in a nested case–control study.MethodsIndividuals who developed GCA after inclusion in a population-based health survey (the Malmö Preventive Medicine Project; N = 33 346) were identified and validated through a structured review of medical records. Four controls for every validated case were selected from the database.ResultsA total of 76 cases with a confirmed incident diagnosis of GCA (61% female, 65% biopsy positive, mean age at diagnosis 70 years) were identified. The median time from screening to diagnosis was 20.7 years (range 3.0–32.1). Cases had significantly lower fasting blood glucose (FBG) at baseline screening compared with controls [mean 4.7 vs 5.1 mmol/l (S.d. overall 1.5), odds ratio (OR) 0.35 per mmol/l (95% CI 0.17, 0.71)] and the association remained significant when adjusted for smoking [OR 0.33 per mmol/l (95% CI 0.16, 0.68)]. Current smokers had a reduced risk of GCA [OR 0.35 (95% CI 0.18, 0.70)]. Both cholesterol [mean 5.6 vs 6.0 mmol/l (S.d. overall 1.0)] and triglyceride levels [median 1.0 vs 1.2 mmol/l (S.d. overall 0.8)] were lower among the cases at baseline screening, with significant negative associations with subsequent GCA in crude and smoking-adjusted models [OR 0.62 per mmol/l (95% CI 0.43, 0.90) for cholesterol; 0.46 per mmol/l (95% CI 0.27, 0.81) for triglycerides].ConclusionDevelopment of GCA was associated with lower FBG and lower cholesterol and triglyceride levels at baseline, all adjusted for current smoking, suggesting that metabolic features predispose to GCA.