Persistent eosinopenia is associated with in-hospital mortality among older patients: unexpected prognostic value of a revisited biomarker

Abstract

Introduction Infection is one of the major causes of mortality and morbidity in older adults. Available biomarkers are not associated with prognosis in older patients. This study aimed to analyze the value of eosinopenia (eosinophil count< 100/mm3) as a prognosis marker among older patients with suspected or confirmed bacterial infection. Methods A retrospective study was performed from 1 January to 31 December 2018 among patients in a geriatrics ward suffering from a bacterial infection treated with antibiotics. Biomarker data including the eosinophil count, neutrophil count and C-reactive protein (CRP) were collected within 4 days after patient diagnosis. Persistent eosinopenia was defined as a consistent eosinophil count< 100/mm3 between Day 2 and Day 4. The association of biomarkers with 30-day hospital mortality in a multivariate analysis was assessed and their predictive ability using the area under the ROC curve (AUC) was compared. Results Our study included 197 patients with a mean age of 90 ± 6 years. A total of 36 patients (18%) died during their stay in hospital. The patients who died were more likely to have persistent eosinopenia in comparison to survivors (78% versus 34%, p < 0.001). In the multivariate analysis, persistent eosinopenia was associated with in-hospital mortality with an adjusted HR of 8.90 (95%CI 3.46–22.9). The AUC for eosinophil count, CRP and neutrophil count between Day 2 and Day 4 were 0.7650, 0.7130, and 0.698, respectively. Conclusion Persistent eosinopenia within 4 days of diagnosis of bacterial infection appeared to be a predictor of in-hospital mortality in older patients.

Association between low eosinophil count and acute bacterial infection, a prospective study in hospitalized older adults

“…This result correlates with a prospective study (96 patients, mean age (SD): 64 [21] years old)), in which patients suffering from bacterial infection with eosinophil count < 0.01 G/L had a faster eosinophil normalization than CRP [19]. More recently, a retrospective study including 197 patients of an age closer to that ouf our study (mean age (SD): 89.6 (5.7)), found that persistent eosinophil count < 0.1 G/L between day 2 and day 4, was associated with in-hospital mortality (HR: 8.9 [3.46-22.9]) [30]. However, eosinophil count < 0.04 G/L combined with WBC > 10 G/L has been studied in an internal medicine ward on 138 patients aged of 71.8 (29.9) y/o, and had high specificity (100%) with a sensitivity of 64% [17].This result was not confirmed in our study, probably because WBC > 10 G/L and a CRP > 20 mg were inclusion criteria and included patients were older (88.8 (5.6) y/o compared to 71.8 y/o).…”

Evaluation of Eosinopenia as a SIRS Biomarker in Critically Ill Horses

“…In human medicine, eosinopenia is considered a reliable prognostic marker in acute ischemic stroke [ 46 ], coronavirus [ 47 ], urticaria [ 48 ], non-cardiac vascular surgery [ 49 ] and acute myocardial infarction [ 50 ]. There is also an association between persistent eosinopenia and high mortality in aged hospitalized patients [ 51 ]. However, despite the extensive bibliography that exists in human medicine, to the authors’ knowledge, there are no studies on eosinopenia as a prognostic marker in horses.…”

Investigating the role of obstructive pulmonary diseases and eosinophil count at admission on all-cause mortality in SARS-CoV-2 patients

“…Since the beginning of the SARS-CoV‑2 pandemic, several studies recognized the potential role of eosinophil count in disease prognosis, mostly associating eosinopenia with poor outcomes [ 25 – 28 ]. Additionally, eosinopenia has also been associated with poor outcomes in patients with bacterial infections [ 29 , 30 ].…”