Relationship between Discordance of Low-Density Lipoprotein and Non-High-Density Lipoprotein Cholesterol and Risk Stratification in Acute Myocardial Infarction

ABSTRACT

Abstract Background: Sizeable proportion of patients have discordant low-density lipoprotein cholesterol (LDL-C) and non-high density lipoprotein cholesterol (NHDL-C). It has been shown that discordance of LDL-C and NHDL-C either underestimates or overestimates coronary risk. Objectıve We assessed whether this discordance has an impact on GRACE and TIMI risk scores in patients with acute myocardial infarction (AMI). Methods: We retrospectively evaluated the data of 198 consecutive patients with AMI. Fasting serum lipid profiles were recorded, GRACE and TIMI scores were calculated. Patients were divided into 3 groups according to LDL-C and NHDL-C percentiles Discordant group LDL-C<NHDL-C (n=38), concordant group LDL-C=NHDL-C (n=112) and discordant group LDL-C>NHDL-C (n=48). GRACE and TIMI scores, mortality and cardiovascular events (heart failure, non-fatal myocardial infarction and angina) at sixth month were compared between these three groups. Differences between these groups were analyzed with One-way ANOVA or Kruskal-Wallis rank test, and with chi-square for percentages. Also, post hoc LSD or Conover-Iman's non-parametric multiple comparison test were used. A p value <0.05 was accepted as statistically significant. Results: TIMI risk score didn't differ between discordant or concordant groups. Mean GRACE (death) and GRACE (death and MI) scores were higher in group with LDL-C<NHDL-C than with LDL-C=NHDL-C and LDL-C>NHDL-C (p=0.029 and 0.008, respectively). Cardiovascular events and mortality at sixth month were not different among groups (p=0.473 and p=0.176, respectively). Conclusion: GRACE score was higher in discordant group with LDL-C<NHDL-C, but there is no difference regarding TIMI scores between discordant and concordant groups in AMI patients.