Identification of neutrophil phenotype categories in geriatric hip fracture patients aids in personalized medicine

Thomas M P Nijdam; Bernard N Jukema; Emma J de Fraiture; Roy Spijkerman; Henk Jan Schuijt; Marcia Spoelder; Coen C W G Bongers; Maria T E Hopman; Leo Koenderman; Falco Hietbrink; Detlef van der Velde

doi:10.1097/OI9.0000000000000291

Identification of neutrophil phenotype categories in geriatric hip fracture patients aids in personalized medicine

OTA Int. 2023 Dec 22;6(5 Suppl):e291. doi: 10.1097/OI9.0000000000000291. eCollection 2023 Dec.

Authors

Affiliations

¹ St. Antonius Ziekenhuis Utrecht, Department of Trauma Surgery, Utrecht, the Netherlands.
² Department of Respiratory Medicine, University Medical Center Utrecht, Utrecht, the Netherlands.
³ Center for Translational Immunology, University Medical Center Utrecht, Utrecht, the Netherlands.
⁴ University Medical Center Utrecht, Department of Trauma Surgery, Utrecht, the Netherlands.
⁵ Department of Physiology, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, the Netherlands.

Abstract

Objectives: The number of geriatric hip fracture patients is high and expected to rise in the coming years, and many are frail and at risk for adverse outcomes. Early identification of high-risk patients is crucial to balance treatment and optimize outcome, but remains challenging. Previous research in patients with multitrauma suggested that neutrophil phenotype analysis could aid in early identification of high-risk patients. This pilot study investigated the feasibility and clinical value of neutrophil phenotype analysis in geriatric patients with a hip fracture.

Methods: A prospective study was conducted in a regional teaching hospital in the Netherlands. At the emergency department, blood samples were collected from geriatric patients with a hip fracture and analyzed using automated flow cytometry. Flow cytometry data were processed using an automated clustering algorithm. Neutrophil activation data were compared with a healthy control cohort. Neutrophil phenotype categories were assessed based on two-dimensional visual assessment of CD16/CD62L expression.

Results: Blood samples from 45 geriatric patients with a hip fracture were included. Neutrophils showed an increased activation profile and decreased responsiveness to formyl peptides when compared to healthy controls. The neutrophil phenotype of all patients was categorized. The incidence of severe adverse outcome was significantly different between the different categories (P = 0.0331). Moreover, patients with neutrophil phenotype category 0 developed no severe adverse outcomes.

Conclusions: Using point-of-care fully automated flow cytometry to analyze the neutrophil compartment in geriatric hip fracture patients is feasible and holds clinical value in determining patients at risk for adverse outcome. This study is a first step toward immuno-based precision medicine for identifying geriatric hip fracture patients that are deemed fit for surgery.

Keywords: flow cytometry; geriatric; hip fracture; inflammatory; neutrophil; trauma.