High suPAR and Low Blood Eosinophil Count are Risk Factors for Hospital Readmission and Mortality in Patients with COPD
Received 4 September 2019
Accepted for publication 21 February 2020
Published 5 April 2020 Volume 2020:15 Pages 733—743
Checked for plagiarism Yes
Review by Single anonymous peer review
Peer reviewer comments 4
Editor who approved publication: Dr Richard Russell
Kjell E J Håkansson,1 Charlotte S Ulrik,1,2 Nina S Godtfredsen,1,2 Thomas Kallemose,3 Ove Andersen,2– 4 Jesper Eugen-Olsen,3 Kristoffer Marsaa,5 Line JH Rasmussen3,6
1Department of Respiratory Medicine, Copenhagen University Hospital Amager and Hvidovre, Hvidovre, Denmark; 2Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark; 3Clinical Research Centre, Copenhagen University Hospital Amager and Hvidovre, Hvidovre, Denmark; 4Emergency Department, Copenhagen University Hospital Amager and Hvidovre, Hvidovre, Denmark; 5Palliative Unit, Copenhagen University Hospital Herlev and Gentofte, Herlev, Denmark; 6Department of Psychology and Neuroscience, Duke University, Durham, NC, USA
Correspondence: Kjell E J Håkansson
Department of Respiratory Medicine, Copenhagen University Hospital Amager and Hvidovre, Kettegård Allé 30 2650, Hvidovre, Denmark
Tel +45 21438688
Introduction: The biomarker soluble urokinase plasminogen activator receptor (suPAR) has been associated with increased mortality in chronic obstructive pulmonary disease (COPD), while elevated blood eosinophils have been associated with better survival. We hypothesized that suPAR and blood eosinophil count are independent risk factors for readmission and mortality after an acute admission in patients with COPD.
Methods: This retrospective cohort study comprised 4022 patients with prevalent COPD acutely admitted to Hvidovre Hospital, Denmark. Irrespective of cause of admission, suPAR and blood eosinophils were measured, and patients were followed up to 365 days. Associations with 365-day respiratory readmission, all-cause readmission and all-cause mortality were investigated by Cox regression analyses adjusted for age, sex, Charlson score and C-reactive protein.
Results: suPAR was significantly elevated in patients who later experienced readmission or died. At 365 days, hazard ratios (HRs) for all-cause readmission and mortality reached 1.61 (95% CI 1.40– 1.85; p< 0.0001) and 3.40 (95% CI 2.64– 4.39; p< 0.0001), respectively, for COPD patients in the fourth suPAR quartile compared to patients in the first suPAR quartile. High blood eosinophils (> 300 cells/μL) were associated with lower risk of mortality (HR 0.49, 95% CI 0.39– 0.62; p< 0.0001) compared with patients with < 150 cells/μL. When stratifying patients by suPAR quartiles and blood eosinophil counts, the highest relative mortality rate was found in patients belonging to both the fourth suPAR quartile and the low blood eosinophil (< 150 cells/μL) group.
Conclusion: In this cohort of COPD patients acutely admitted to a hospital, elevated suPAR concentrations were associated with both higher risk of all-cause readmission and mortality, whereas higher blood eosinophil count was associated with lower risk of mortality.
Keywords: acute admission, biomarker, hospitalization, prognosis, retrospective cohort, inflammation