Combined effect of lipoprotein(a) and C-reactive protein on future cardiovascular outcomes after acute myocardial infarction

Background Both lipoprotein(a) (Lp[a]) and C-reactive protein (CRP) have been reported as risk factors of cardiovascular events in patients with coronary artery disease. Purpose The aim of the present study is to evaluate the impact of combined Lp(a) and CRP levels for future cardiovascular events in acute myocardial infarction (AMI) patients. Methods We retrospectively investigated 2,425 consecutive patients with AMI who underwent percutaneous coronary intervention in our institution from January 2004 to December 2017. We finally enrolled 1,152 patients for whom Lp(a) and CRP were available and who were discharged alive. Patients were assigned to 4 groups according to their median Lp(a) and CRP levels (15 mg/100ml and 0.30 mg/dL, respectively). The primary endpoints were major adverse cardiac or cerebrovascular events (MACCEs), including cardiovascular death, MI and stroke between 30 days to 3 years after AMI. Results During median follow-up period of 2.5 years, 78 cases of MACCEs (6.7%) were identified. The rates of MACCE significantly differed among the groups (log-rank test, p=0.0007) and patients in both high Lp(a) and CRP group had clearly higher incidence of MACCE compared with other group patients. After adjustment for established risk factors, high Lp(a) with high CRP level was significantly associated with MACCE (hazard risk 2.58, 95% confidence interval 1.32-5.04, p=0.006, both low Lp(a) and CRP group as reference). Conclusions The presence of both high Lp(a) and CRP level conferred a synergistic adverse effect on the risk for recurrence cardiovascular events in following AMI.