Aims  To assess the prognostic impact of HbA1cand blood glucose level in patients with acute ST segment elevation myocardial infarction and without diabetes. The relationship between HbA1cand acute hyperglycemia was also explored.

Methods and results We evaluated 4793 ST-segment elevation myocardial infarction patients with baseline HbA1cand three glucose measurements in the first 24 h. First, patients were stratified into quintiles by HbA1cand mean/admission glucose level. A total of 373 deaths (7.8%) occurred at 7 days, and 486 deaths (10.1%) occurred at 30 days. There were no significant differences in 7- and 30-day mortality, and major adverse cardiovascular event rates across HbA1cquintiles (< 5.3%, 5.3 to < 5.6%,5.6 to < 5.9%, 5.9 to < 6.5%, and ≥6.5%; P for trend > 0.05). The risks of mortality and major adverse cardiovascular events were significantly increased in patients with higher glucose quintiles and lower quintile compared with the middle quintile after multivariable adjustment (P < 0.001). Patients were then reclassified into four groups according to mean/admission glucose and HbA1clevels. The group wit elevated glucose and non-elevated HbA1cwas associated with the highest mortality and major adverse cardiovascular event risk (P < 0.001).

Conclusions  Unlike acute hyperglycemia, an elevated HbA1clevel was not a risk factor for short-term outcomes in ST-segment elevation myocardial infarction patients without diabetes. Patients with acute hyperglycemia and non-elevated HbA1cwere associated with the worst prognosis. That suggests chronic glycemic control/HbA1clevel may help to recognize stress-induced hyperglycemia and identify high risk patients.