Effect of Serum Total Cholesterol on Hemorrhagic Complications following Thrombolytic Therapy for Acute Myocardial Infarction

Abstract

Despite the well-known and widely publicized adverse effects of hypercholesterolemia on the cardiovascular system, cholesterol is a vital component of cellular membranes, maintaining vascular integrity and normal platelet activatability. To test the hypothesis that a low serum total cholesterol concentration increases bleeding risk following thrombolytic therapy, a comparison of in-hospital hemorrhagic events was made between 132 patients with myocardial infarction divided into three distinct groups. Group 1 patients (n = 44) had an admitting serum total cholesterol of less than 200 mg/dl, while group 2 (n = 57) and group 3 (n = 31) patients had cholesterol levels of 200-249 and greater than or equal to 250 mg/dl, respectively. There were no significant differences between groups in either minor hemorrhagic events (p = 0.85), major hemorrhagic events (p = 0.73) or transfusion requirements (p = 0.45). In addition, the primary sites of bleeding did not differ. Over the 2-year study period, a total of four intracerebral events were identified. As with minor and other major hemorrhagic events, an association with serum total cholesterol and intracerebral hemorrhage was not observed (p = 0.29). However, advanced age (greater than 65 years; p = 0.04) and a total dose of recombinant tissue-type plasminogen activator in excess of 1.5 mg/kg body weight (p less than 0.001) were identified by multivariate analysis as risk factors for intracerebral hemorrhage. Thus, although cholesterol is vital for maintaining vascular integrity and normal hemostasis, relatively low serum levels are not a risk factor for hemorrhagic complications following thrombolytic therapy.