Acute glucose dysmetabolism in the early phase of ST-elevation myocardial infarction: the age response

In elderly patients with AMI, hyperglycaemia is associated with increased mortality. Recently it has been observed that insulin resistance, as assessed by the HOMA index, proved an independent predictor of in-hospital mortality. The interaction between age and glucose metabolism response in the acute phase of patients with STEMI without previously known diabetes has not yet been explored. We aimed to assess this relationship in 346 consecutive patients with STEMI admitted to our ICCU after primary PCI. When compared with the other age subgroups, the very oldest patients (aged > 79 years) showed the lowest LVEF (p=0.011), the highest incidence of 2- and 3-vessel coronary artery disease (p=0.002), and, finally, the highest mortality (p=0.037). Advancing age was associated with increased values of fibrinogen (p=0.022) and ESR (p=0.001), as well as of NT-pro-BNP (p<0.001). The very oldest patients (aged > 79 years) exhibited the highest values of glycaemia and peak glycaemia, while the incidence of insulin resistance (as inferred by HOMA index) remained unchanged across the age subgroups. This glycaemic pattern was confirmed after exclusion of patients with HbA(1c) > 6.5%, that is patients with a poor glycaemic control in the previous 2-3 months. In the acute phase of STEMI acute glucose metabolism is affected by age, since older patients showed the highest glucose levels and the poorest glycaemic control during ICCU stay despite the lack of differences in insulin resistance incidence.