PT - JOURNAL ARTICLE AU - Esther Wittermans AU - Philip A. van der Zee AU - Hongchao Qi AU - Ewoudt M.W. van de Garde AU - Claudine A. Blum AU - Mirjam Christ-Crain AU - Diederik Gommers AU - Jan C. Grutters AU - G. Paul Voorn AU - Willem Jan W. Bos AU - Henrik Endeman TI - Community-acquired pneumonia subgroups and differential response to corticosteroids: a secondary analysis of controlled studies AID - 10.1183/23120541.00489-2021 DP - 2022 Jan 01 TA - ERJ Open Research PG - 00489-2021 VI - 8 IP - 1 4099 - http://openres.ersjournals.com/content/8/1/00489-2021.short 4100 - http://openres.ersjournals.com/content/8/1/00489-2021.full SO - erjor2022 Jan 01; 8 AB - Background Latent class analysis (LCA) has identified subgroups with meaningful treatment implications in acute respiratory distress syndrome. We performed a secondary analysis of three studies to assess whether LCA can identify clinically distinct subgroups in community-acquired pneumonia (CAP) and whether the treatment effect of adjunctive corticosteroids differs between subgroups.Methods LCA was performed on baseline clinical and biomarker data from the Ovidius trial (n=304) and the Steroids in Pneumonia (STEP) trial (n=727), both randomised controlled trials investigating adjunctive corticosteroid treatment in CAP, and the observational TripleP cohort (n=201). Analyses were conducted independently in two cohorts (Ovidius–TripleP combined and the STEP trial). In both cohorts, differences in clinical outcomes and response to adjunctive corticosteroid treatment were examined between subgroups identified through LCA.Results A two-class model fitted both cohorts best. Class 2 patients had more signs of systemic inflammation compared to class 1. In both cohorts, length of stay was longer and in-hospital mortality rate was higher in class 2. In the Ovidius trial, corticosteroids reduced the median length of stay in class 2 (6.5 versus 9.5 days) but not in class 1 (p-value for interaction=0.02). In the STEP trial, there was no significant interaction for length of stay. We found no significant interaction between class assignment and adjunctive corticosteroid treatment for secondary outcomes.Conclusions In two independent cohorts, LCA identified two classes of CAP patients with different clinical characteristics and outcomes. Given the different response to adjunctive corticosteroids in the Ovidius trial, LCA might provide a useful basis to improve patient selection for future trials.Latent class analysis of baseline clinical and biomarker data identified two distinct classes of patients with community-acquired pneumonia in two cohorts. In one cohort, the response to adjunctive corticosteroid treatment differed between classes. https://bit.ly/3ClR92L