Ethnic variations in neutrophil count as predictors of prognosis following acute myocardial infarction

Abstract

AIMS: Elevated neutrophils are associated with a poor prognosis after acute myocardial infarction (AMI) but it is not known if ethnicity influences the association between neutrophil count and outcome. We aimed to describe the temporal dynamics of neutrophils after AMI, and assess the interaction between ethnicity, neutrophil count, and outcomes after AMI. METHODS: Consecutive patients presenting with AMI between 2016 and 2023 were divided into two groups according to their median neutrophil count. Ethnicity was dichotomised as white and other ethnic groups combined (referred to as 'ethnic minorities'). The primary outcome was in-hospital mortality, with a secondary outcome of 60-day mortality. RESULTS: In our study of 3062 AMI patients (76 % white, 24 % from ethnic minority groups), we found that neutrophil counts rose early post AMI, which coincided with a nadir of the other cell groups. We identified a relative baseline neutropenia in ethnic minority individuals, compared to white individuals (6.85 vs 8.42 × 10 CONCLUSIONS: We report ethnicity-specific leucocyte dynamics after AMI. Furthermore, neutrophil count is associated with a disproportionate risk in ethnic minority compared with white individuals. Understanding post-AMI inflammation and its interaction with ethnicity is essential in providing personalised prognostication and patient management.