ABSTRACT
The incidence of coronary heart disease [CHD] is increasing in Egypt. There is a need for identification of some risk factors that could predict the occurrence of myocardial infarction [MI] in susceptible persons such as those with hypercholesterolemia. This case control study was done to define whether increased serum lipoprotein [a] [Lp [a]] is a risk factor for developing MI and its relation to common hypercholesterolemia. Lp [a] was estimated in a group of middle aged men [n = 17] with a past history of MI within the past two years and another age matched group of men [n = 18] with no history of CHD. Both groups were showing the criteria of having common hypercholesterolemia [low density lipoprotein [LDL] cholesterol between 135-277 mg/dl, triglycerides < 337 mg/d1 and with no family history of hypercholesterolemia and/or CHD]. The Lp [a] levels also measured in a group of healthy middle aged medical staff with no history of CHD and with normal LDL cholesterol [< 135 md/d1]. The Lp [a] serum levels were significantly higher in the group with MI [geometric mean 0.62 [95% confidence interval 0.35 to 1.14] vs 0.28 [0.2 to 0.41] g/L, p = 0.02], but there were no significant differences in other variables. Logistic regression analysis showed that Lp [a] was the only significant predictor of MI [p 0.02]. The odds ratio of MI, adjusted for age, smoking, blood presure, and apolipoprotein B, for an Lp [a] of > 0.57 g/L was 16.4, 95% confidence interval 2.2 to 125.4 [p = 0.001]. It was concluded that Lp [a] is an independent and satisfying index for risk of developing MI and could be used as a laboratory tool for identifying persons prone to suffer from the disease