Abstract 3518: High Remnant Lipoprotein Levels Adversely Affect Short- and Long-term Outcomes for Patients with Acute Myocardial Infarction and Type 2 Diabetes Mellitus
Diabetes mellitus (DM) adversely affects prognosis in patients with acute myocardial infarction (AMI). Evidence shows that lipids-lowering therapy rather than glycemic control reduces macrovascular events in these patients, but it remains unclear which lipoprotein fractions contribute to negative effects. We previously showed that high levels of remnant lipoprotein, a triglyceride-rich lipoprotein, were an independent risk of future coronary events in patients with chronic coronary artery disease and DM. This study examined the hypothesis that remnant lipoproteinemia may adversely affect short- and long-term prognosis in patients with AMI and DM.
Methods and Results: A prospective study was performed in 268 consecutive patients with Type 2 DM who were enrolled on day 5 after AMI. Fasting serum levels of remnant lipoproteins (remnant-like lipoprotein particles cholesterol; RLP-C) on day 5 after AMI were measured by an immunoseparation method. Adverse events, a composite of cardiac death, nonfatal MI, or recurrent unstable myocardial ischemia leading to unplanned revascularization therapy, were assessed during follow-up periods of 30 days and 1 year after AMI. Events rates were higher in patients with than without higher RLP-C levels (≥ 5.5 mg/dL, 50th percentile of the distribution) during both short- and long-term follow-up periods (30 days post-MI, 8.2% [11/134 patients] vs. 2.2% [3/134 patients], p <0.05; 1 year post-MI, 15%  vs. 7.5% , p <0.05). In multivariate Cox hazard analyses, higher RLP-C levels were a significant predictor of adverse events during 30 days and 1 year independently of enrollment levels of glucose, LDL-C, and non-HDL-C (hazard ratios 2.1 and 1.7, 95% CI 1.8 – 3.9 and 1.3 – 4.0, respectively, both p<0.01). RLP-C levels were significantly correlated with C-reactive protein levels and intimal thickening of carotid artery at enrollment (r =0.30 and 0.39, respectively, both p<0.01).
Conclusions: High remnant lipoprotein levels adversely affect short- and long-term outcomes in patients with AMI and Type 2 DM. The pro-inflammatory and pro-atherothrombogenic effects of remnant lipoprotein may contribute to coronary plaques instability in patients with AMI and Type 2 DM.