Haptoglobin Polymorphism Predicts 30-Day Mortality and Heart Failure in Patients With Diabetes and Acute Myocardial Infarction

Technion - Israel Institute of Technology, H̱efa, Haifa, Israel
Diabetes (Impact Factor: 8.1). 10/2005; 54(9):2802-6. DOI: 10.2337/diabetes.54.9.2802
Source: PubMed


Patients with diabetes presenting with acute myocardial infarction (AMI) have an increased rate of death and heart failure. Patients with diabetes homozygous for the haptoglobin (Hp) 1 allele (Hp 1-1) develop fewer vascular complications. We tested the hypothesis that Hp type is related to the outcome of patients with diabetes presenting with AMI. We prospectively assessed the relationship between Hp type and 30-day mortality and heart failure in 1,437 patients with AMI (506 with diabetes). Multivariate logistic regression identified a significant interaction between Hp type and diabetes status on these outcome measures. Hp type was not related to outcome among patients without diabetes. In contrast, Hp 1-1 was associated with a strong protective effect with regard to the primary end point of death (OR 0.14, P = 0.015) and for death and heart failure (OR 0.35; 95% CI 0.15-0.86, P = 0.018) among patients with diabetes. Finally, among patients with diabetes, Hp 1-1 was associated with smaller infarct size. This study demonstrates that in patients with diabetes and AMI, the Hp type is an important determinant of clinical outcome and infarct size.

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Available from: Simcha Meisel, Nov 29, 2015
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    • "More recent investigations employing native Hp:Hb ligand appeared to suggest poor or even lack of dependence on CD163 for IL-6 or IL-10 signalling pathways, depending on the type of polymorphic haptoglobin variant employed [17] [18]. Since the haptoglobin 2 allele is linked to a host of adverse clinical cardiovascular events, [19] [20] [21] [22] [23] it is important to understand Hp genotype-dependent disease mechanisms in CD163 + macrophages in greater detail, to guide informed interdictions in vulnerable individuals. Here we have examined IL-10 signalling pathways during scavenging of polymorphic Hp2-2:Hb versus Hp1-1:Hb complexes in CD163 + human monocyte-derived macrophages. "
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    • "One study [19] found that individuals with T2DM and the HP2-2 genotype had increased risk for CVD events. In addition, Suleiman et al. in 2005 [20] found that individuals with T2DM and the HP 1–1 phenotype had decreased 30-day mortality and heart failure after acute myocardial infarction compared to individuals with the HP 2–2 phenotype, again suggesting the HP 2-2 phenotype as the risk phenotype. This association was not seen in individuals without T2DM. "
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