Role of ApoE gene polymorphism and nonconventional biochemical risk factors among very young individuals (aged less than 35 years) presenting with acute myocardial infarction.

Background: Incidence rate of acute myocardial infarction (MI) has increased in younger population over the years. The young patients have a different risk profile, presentation, and prognosis than the elderly. Hence, it is essential to understand the risk factors in young patients for proper treatment.

Methods: Apolipoprotein E (ApoE) polymorphism and biochemicals such as total cholesterol, serum triglycerides, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), apolipoprotein A1 (ApoA1), apolipoprotein B (ApoB), lipoprotein(a), insulin, interleukin-6, homocysteine, fibrinogen, and highly sensitive C-reactive protein were investigated in very young MI (yMI patients; age ≤ 35 years; n = 125), in old MI (oMI patients; age >35 and < 80 years; n = 111), and healthy controls (age ≤35 years; n = 103).

Results: HDL-C was significantly lower in yMI patients than in controls (p = 2.63E-04) and oMI patients (p = 1.29E-05). ApoA1 was also lowest in yMI patients, but significant only in comparison to controls (p = 2.62E.04). The yMI group had the highest ratios of total cholesterol:HDL-C (p = 0.027 in yMI patients versus controls and p = 0.018 in yMI patients versus oMI patients), LDL-C:HDL-C (p = 0.002 in yMI patients versus controls and p = 0.005 in yMI patients versus oMI patients), and ApoB:ApoA1 (p = 8.75E-05 in yMI patients versus controls and p > 0.05 in yMI patients versus oMI patients). No significant pattern of ApoE polymorphisms was observed.

Conclusion: The lower level of HDL-C and ApoA1 and higher ratios of total cholesterol:HDL-C, LDL-C:HDL-C, and ApoB:ApoA1 are risk factors for MI in young patients.