Impact of glycemic gap on 30-day adverse outcomes in patients with acute ST-segment elevation myocardial infarction

Abstract

Background and aims: Stress-induced hyperglycemia (SIH) generally occurs in critical illness. Recently, glycemic gap (GAP) has been considered to be a superior indicator of SIH. However, data on the association between GAP and prognosis in ST-segment elevation myocardial infarction (STEMI) is limited. This observational study aimed to estimate the prognostic value of GAP_mean, defined as the difference between mean blood glucose level (MGL) within 24 h after admission and A1c-derived average glucose (ADAG), in patients with acute STEMI.

Methods: A total of 4952 patients with acute STEMI were included in the final analysis, and they were divided into four groups according to GAP_mean quartiles and diabetes mellitus (DM). The primary outcomes were all-cause mortality and major adverse cardiovascular events (MACEs). Cox proportional hazards regression analysis and net reclassification improvement (NRI) analysis were performed.

Results: At 30 days of follow-up, 324 (6.5%) deaths and 569 (11.5%) MACEs occurred. With the elevation of GAP_mean, the incidence of all-cause mortality (4.0%, 5.6%, 6.5%, and 10.1%) and MACEs (7.3%, 9.6%, 11.4%, and 17.7%) significantly increased. Receiver operating characteristic curve analysis demonstrated that GAP_mean was superior to admission blood glucose (ABG) and GAP_adm (defined as the difference between ABG and ADAG) to detect adverse outcomes. Multivariate Cox regression analysis revealed that elevated GAP_mean was independently associated with all-cause death and MACEs. With the first quartile as a reference, the hazards ratios (HRs) for all-cause death in the second, third, and fourth quartiles were 1.49 (95% CI 1.02-2.18), 1.58 (95% CI 1.09-2.30), and 2.11 (95% CI 1.48-3.02), respectively, and the HRs for MACEs were 1.40 (95% CI 1.05-1.86), 1.60 (95% CI 1.21-2.11), and 2.17 (95% CI 1.66-2.83), respectively, which were independent of DM status. Continuous NRI analysis revealed that GAP_mean significantly improved risk stratification for all-cause mortality and MACEs by 21.6% and 19.8%, respectively.

Conclusions: The glycemic gap between MGL within 24 h after admission and ADAG was independently associated with 30-day all-cause mortality and MACEs in patients with acute STEMI, which was not affected by DM status. Further, the glycemic gap provided incremental accuracy in the risk stratification of STEMI.

Keywords: All-cause mortality; Glycemic gap; Major adverse cardiovascular events; ST-segment elevation myocardial infarction; Stress-induced hyperglycemia.