Purpose: This study examines the relation between lipoprotein (a) protein levels and other lipid parameters and coronary artery disease in white and black patients.
Patients and methods: Plasma lipoprotein (a) protein levels were measured prior to coronary angiography in a population of 127 white and 111 black patients. Each angiogram was given a total coronary artery disease score based on the number and severity of atherosclerotic coronary lesions.
Results: White and black patients exhibited no differences in total plasma cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides. Black patients had higher lipoprotein (a) protein levels than white patients (8.6 versus 4.0 mg/dL; p < 0.0001). The extent and severity of coronary artery disease was the same in white and black patients. White and black patients with coronary artery disease had higher lipoprotein (a) levels than patients without coronary lesions (4.37 versus 1.99 mg/dL, p = 0.027 for white; 9.23 versus 6.87 mg/dL, p = 0.072 for black). In both groups of patients, there was a weak but significant positive correlation between lipoprotein (a) protein levels and coronary artery disease score.
Conclusion: Lipoprotein (a) is higher in patients with coronary artery disease. Black patients have higher plasma lipoprotein (a) protein levels than white patients and a comparable degree of coronary artery disease. It follows that the cardiovascular pathogenicity of lipoprotein (a) is not significantly greater in black patients despite higher lipoprotein (a) levels.