Effectiveness of the GRACE risk score according to troponin elevation in patients admitted with non-ST elevation acute coronary syndrome: a post-hoc analysis of the UKGRIS cluster RCT

Abstract

Abstract Background In the United Kingdom GRACE Risk Score (UKGRIS) phase 3 parallel group cluster randomised controlled trial, the Global Registry of Acute Coronary Events (GRACE) risk score (GRS) did not improve adherence to guideline recommended management or reduce cardiovascular events at 12 months in patients admitted with suspected non ST elevation acute coronary syndrome (NSTEACS) compared with standard care.(1) Troponin elevation in the context of NSTEACS is associated with high risk of adverse clinical events, including myocardial infarction, heart failure and death,(2) and in this population the GRS may impact on outcomes. Purpose To investigate the effectiveness of the GRS compared with standard care according to troponin elevation in patients admitted with NSTEACS. Methods Post-hoc analysis of primary and secondary outcome measures according to troponin elevation on admission of the UKGRIS trial across 42 sites in England. Patients aged ≥18 years admitted with suspected NSTEACS and a minimum follow-up of 24 months were eligible. Primary outcome measures were use of guideline recommended management and time to the composite of cardiovascular death, non-fatal myocardial infarction, new onset heart failure hospital admission, and readmission for cardiovascular event. Secondary measures included the duration of hospital stay, EQ-5D-5L (five domain, five level version of the EuroQoL index), and the composite endpoint components. Results A total of 3050 patients were randomised in UKGRIS, of whom 2602 had troponin elevation. The effect of GRS compared with standard care on the uptake of guideline recommended care was greater for participants with troponin elevation (odds ratio 1.34, 95% CI 0.84 to 2.13) compared to those without (0.88, 0.52 to 1.47) (Table 1). There was an interaction between troponin elevation and effect of GRS versus standard care on guideline uptake (relative odds ratio 1.52, 95% CI 1.16 to 2.00, P < 0.01). The time to the first composite event was not improved by the GRS among participants with (hazard ratio 0.86, 95% CI 0.67 to 1.12) or without troponin elevation (1.19, 0.80 to 1.77) (Figure 1), with no interaction (relative hazards ratio 0.73, 95% CI 0.51 to 1.03, P = 0.07), and none of the individual components of the composite outcome had a significant interaction between randomisation to GRACE and troponin elevation. Baseline adjusted EQ-5D-5L utility at 12 months and duration of hospital stay at 24 months were not statistically significantly different for the two trial arms among participants with or without troponin elevation. Conclusions For suspected NSTEACS, the effect of the GRS compared with standard care on uptake of recommended processes was greater in those with elevated troponin than in those without. However, this did not translate to a reduction in the composite primary outcomes or secondary outcomes at 24 months.