Cluster Analysis to Explore Clinical Subphenotypes of Eosinophilic Granulomatosis With Polyangiitis.

OBJECTIVE: Previous studies suggested that distinct phenotypes of eosinophilic granulomatosis with polyangiitis (EGPA; formerly known as Churg-Strauss syndrome) could be determined by the presence or absence of antineutrophil cytoplasmic antibodies (ANCA), reflecting predominant vasculitic or eosinophilic processes, respectively. This study explored whether ANCA-based clusters or other clusters can be identified in EGPA. METHODS: This study used standardized data of 15 European centers for patients with EGPA fulfilling widely accepted classification criteria. We used multiple correspondence analysis, hierarchical cluster analysis, and a decision tree model. The main model included 10 clinical variables (musculoskeletal [MSK], mucocutaneous, ophthalmological, ENT, cardiovascular, pulmonary, gastrointestinal, renal, central, or peripheral neurological involvement); a second model also included ANCA results. RESULTS: The analyses included 489 patients diagnosed between 1984 and 2015. ANCA were detected in 37.2% of patients, mostly perinuclear ANCA (85.4%) and/or antimyeloperoxidase (87%). Compared with ANCA-negative patients, those with ANCA had more renal (P < 0.001) and peripheral neurological involvement (P = 0.04), fewer cardiovascular signs (P < 0.001), and fewer biopsies with eosinophilic tissue infiltrates (P = 0.001). The cluster analyses generated 4 (model without ANCA) and 5 clusters (model with ANCA). Both models identified 3 identical clusters of 34, 39, and 40 patients according to the presence or absence of ENT, central nervous system, and ophthalmological involvement. Peripheral neurological and cardiovascular involvement were not predictive characteristics. CONCLUSION: Although reinforcing the known association of ANCA status with clinical manifestations, cluster analysis does not support a complete separation of EGPA in ANCA-positive and -negative subsets. Collectively, these data indicate that EGPA should be regarded as a phenotypic spectrum rather than a dichotomous disease.

[Criteria for evaluation of response to biologics in severe asthma - the Biologics Asthma Response Score (BARS)]. / Kriterien zur Evaluation des Ansprechens auf Biologika bei schwerem Asthma ­ der Biologics Asthma Response Score (BARS).

BACKGROUND: The introduction of monoclonal antibodies (biologics) has revolutionized the therapy of severe asthma. Even though there is a response in the majority of patients, the degree of response varies. To date criteria for assessment of response to biologics are not consistently defined. AIM: To define criteria for evaluation of response to biologics that are precise, simple and suitable for daily use in order to guide decision-making regarding continuation, switching or stopping of biological therapy. METHODS: 8 physicians with large experience in this indication, supported by a data-scientist, developed a consensus on criteria to evaluate response to biologics in patients with severe asthma. RESULT: We developed a combined score based on current literature, own experience and practicability. It uses the main criteria exacerbations, oral corticosteroid (OCS) therapy and asthma control (asthma control test, ACT). We defined thresholds for "good response", "response" and "insufficient response" rated with a score of "2", "1" and "0" respectively: annual exacerbations ("0 or reduction ≥ 75 %", reduction 50-74 %", "reductio  < 50 %"), daily OCS dose ("stopping or reduction ≥ 75 %", "reduction 50-74 %", "reduction < 50 %"), asthma control (ACT increase ≥ 6 or ≥ 3 with result ≥ 20", "ACT increase 3-5 with result < 20", "ACT increase < 3"). Additional individual criteria like lung function and comorbidities may be important for evaluation of response. We propose 3, 6 and 12 months timepoint for assessment of tolerability and response. Using the combined score, we developed a scheme to guide the decision whether switching the biologic should be considered. CONCLUSION: The Biologic Asthma Response Score (BARS) serves as objective and simple tool to evaluate response to biologic therapy using the three main criteria exacerbations, OCS use and asthma control. A validation of the score was initiated.

Criteria for evaluation of response to biologics in severe asthma - the Biologics Asthma Response Score (BARS).

BACKGROUND: The introduction of monoclonal antibodies (biologics) has revolutionized the therapy of severe asthma. Even though there is a response in the majority of patients, the degree of response varies. To date criteria for assessment of response to biologics are not consistently defined. AIM: To define criteria for evaluation of response to biologics that are precise, simple and suitable for daily use in order to guide decision-making regarding continuation, switching or stopping of biological therapy. METHODS: 8 physicians with large experience in this indication, supported by a data-scientist, developed a consensus on criteria to evaluate response to biologics in patients with severe asthma. RESULT: We developed a combined score based on current literature, own experience and practicability. It uses the main criteria exacerbations, oral corticosteroid (OCS) therapy and asthma control (asthma control test, ACT). We defined thresholds for "good response", "response" and "insufficient response" rated with a score of "2", "1" and "0" respectively: annual exacerbations ("0 or reduction ≥ 75 %", "reduction 50-74 %", "reductio < 50 %"), daily OCS dose ("stopping or reduction ≥ 75 %", "reduction 50-74 %", "reduction < 50 %"), asthma control ("ACT increase ≥ 6 or ≥ 3 with result ≥ 20", "ACT increase 3-5 with result < 20", "ACT increase < 3"). Additional individual criteria like lung function and comorbidities may be important for evaluation of response. We propose 3, 6 and 12 months timepoint for assessment of tolerability and response. Using the combined score, we developed a scheme to guide the decision whether switching the biologic should be considered. CONCLUSION: The Biologic Asthma Response Score (BARS) serves as objective and simple tool to evaluate response to biologic therapy using the three main criteria exacerbations, OCS use and asthma control. A validation of the score was initiated.