Relation of the stress hyperglycaemia ratio to residual risk in anticoagulated patients with atrial fibrillation: A report from the prospective Murcia AF Project III cohort

Abstract

INTRODUCTION: Atrial fibrillation (AF) carries residual thromboembolic and cardiovascular risk despite oral anticoagulation (OAC). The stress hyperglycaemia ratio (SHR), derived from admission glucose and glycated haemoglobin (HbA1c), integrates information on both acute glycaemic fluctuations and chronic glycaemic burden. SHR has been associated with adverse outcomes in high-risk populations, but its utility in stratifying residual risk in anticoagulated AF patients remains uncertain. This study evaluated SHR as a marker of thromboembolic and cardiovascular risk in this setting. METHODS: This prospective cohort study included consecutive AF outpatients initiating OAC between January 2016 and November 2021. SHR was calculated, and patients were stratified into low and high SHR groups. Primary outcomes were thromboembolic events (i.e. composite of ischaemic stroke [IS], transient ischaemic attack [TIA] or systemic embolism) and major adverse cardiovascular events (MACEs), comprising myocardial infarction, IS, TIA or cardiovascular death. Secondary outcomes included cardiovascular and all-cause death. Associations were assessed using restricted cubic splines and multivariable Cox models. RESULTS: A total of 1479 patients (53.1% female; median age 76 years [interquartile range 69-82]; follow-up 1.87 years) were included. During follow-up, 80 thromboembolic events (5.4%) and 107 MACE (7.2%) occurred. Incidence rates were higher in the low SHR group compared with the high SHR group for both thromboembolic events (4.26 vs 2.50 per 100 person-years) and MACE (5.64 vs 3.34 per 100 person-years). SHR was significantly associated with both thromboembolic risk (p-overall = 0.005; non-linear p = 0.015) and MACE (p-overall <0.001; linear p = 0.053). In multivariable Cox models, low SHR was independently associated with increased risk of thromboembolic events (adjusted hazard ratio [aHR] 1.73; 95% confidence interval [CI] 1.08-2.76; p = 0.022) and MACE (aHR 1.58; 95% CI 1.06-2.37; p = 0.025), compared with the high SHR group. No significant associations were observed for secondary outcomes. CONCLUSION: In anticoagulated AF patients, low SHR was independently associated with higher residual thromboembolic and cardiovascular risk.