Hypercholesterolemia and atherosclerosis in primary biliary cirrhosis: what is the risk?

Abstract

Hypercholesterolemia is commonly associated with primary biliary cirrhosis. In the general population, elevated serum cholesterol is associated with an increased risk of atherosclerosis. The relative risk has been poorly defined in primary biliary cirrhosis patients with hyperlipidemia. In addition, the hyperlipidemic state seen with primary biliary cirrhosis has not been well studied. We prospectively observed 312 patients with primary biliary cirrhosis for a median of 7.4 yr. During this period, 128 patients died. The incidence of atherosclerotic death in patients with primary biliary cirrhosis was not statistically different when compared with an age-matched and sex-matched U.S. control population. A similar group of 50 consecutive PBC patients had detailed serum lipid profiles. Findings included progressive increases in total cholesterol and low-density lipoprotein cholesterol with an increasing histological stage or severity of disease. High-density lipoprotein cholesterol was elevated in all stages, with the highest levels in histological stage 2 and 3 disease. Triglycerides were normal or slightly elevated in all stages. Apoprotein A-I was elevated in all but histological stage 4 disease. Our study suggests the hyperlipidemia associated with primary biliary cirrhosis does not place these patients at risk for atherosclerotic death. In light of the limitations imposed by our relatively small sample size, however, additional patients should be studied. Furthermore, an examination of the pathophysiological mechanisms leading to hypercholesterolemia should be the topic of further study.