Higher post-acute myocardial infarction plasma haptoglobin level is associated with poor long-term overall survival

To evaluate the association of post-acute myocardial infarction (AMI) plasma haptoglobin (Hp) levels with long-term overall survival in AMI patients.

Patients who were diagnosed of AMI were recruited and their Hp phenotypes and plasma levels were determined. According to previously reported cutoff point for Hp level (288.4ng/ml), patients were classified as higher Hp group (>288.4ng/ml) and lower Hp group (≤288.4ng/ml). The primary outcome was overall survival. This study recruited and followed a total of 117 patients for a median of 11.0 (3.2-17.6) years. Higher Hp group had 46 patients (39.3%) and lower Hp group had 71 patients (60.7%). Twelve patients had Hp 1-1 (10.3%), 50 with Hp 2-1 (42.7%), and 55 with Hp 2-2 (47.0%). The lower Hp group had significantly better overall survival (174.1 [51.6-212.5] vs. 106.5 [22.2-209.1], P=0.037). There was no significant difference in overall survival between the three phenotype groups (P=0.477). Multivariate regression analysis revealed that increased age (adjusted HR=1.06, 95% CI: 1.03-1.10, P<0.001) and higher Hp level (adjusted HR=1.65, 95%=1.02-2.67, P=0.040) were significantly associated with poor overall survival.

Higher post-AMI plasma Hp level was independently associated with poor overall survival in AMI patients. No significant difference in overall survival was noted between three Hp phenotype groups. Acute phase Hp level might reflect the severity of oxidative stress during inflammation process.