Early coronary revascularization among stable patients with non-ST-segment elevation acute coronary syndromes: the role of diabetes and age

Abstract Background Diabetes mellitus affects 10-30% patients hospitalized with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) and two-fold higher mortality risk compared to non-diabetics. Despite higher post-PCI complications in diabetic patients, guidelines advise early invasive NSTE-ACS treatment for all, based expert opinion, and limited evidence. Purpose To investigate the impact of an early coronary revascularization (<24 hours) compared with initial conservative strategy on clinical outcomes in diabetic patients with NSTE-ACS who are in stable condition at hospital admission. Methods The ISACS-TC database was queried for a sample of diabetic and nondiabetic patients with diagnosis of NSTE-ACS. Patients with cardiac arrest, hemodynamic instability, and serious ventricular arrhythmias were excluded. The characteristics between groups were adjusted using logistic regression and inverse probability of treatment weighting models. Primary outcome measure was all cause 30-day mortality. Risk ratios (RRs) and odds ratios (ORs) with their 95% CIs were employed. Results Of the 7,589 NSTE-ACS patients identified, 2,343 were diabetics. The data show a notable reduction in mortality for the elderly undergoing early revascularization compared to those receiving an initial conservative strategy both in the diabetic (3.3% versus 6.7%; RR: 0.48; 95% CI: 0.28-0.80) and nondiabetic patients (2.7% versus 4.7%: RR: 0.57; 95% CI: 0.36-0.90). In multivariate analyses, diabetes was a strong independent predictor of mortality in the elderly (OR: 1.43; 95% CI: 1.03-1.99), but not in the younger patients OR: 1.04; 95% CI: 0.53-2.06). Conclusions Early coronary revascularization does not lead to any survival advantage within 30 days from admission in young NSTE-ACS patients who present to hospital in stable conditions with and without diabetes. An early invasive management strategy may be best reserved for the elderly. Factors beyond revascularization are of considerable importance for outcome in elderly diabetic subjects with NSTE-ACS.