Apolipoprotein E polymorphism, a marker of disease severity in primary biliary cirrhosis?

Background/Aims: To determine whether the apolipoprotein E (apo-E) polymorphism is associated with the risk of primary biliary cirrhosis (PBC), the severity of the disease and its response to ursodeoxycholic acid (UDCA) therapy. Methods: The apo-E genotype was determined in 72 PBC patients. Genotype and allele distributions were compared with those found in the French general population. Laboratory parameters obtained before and after 1- and 4-year UDCA treatment were compared according to the apo-E allele carrier status. Results: Apo-E allele and genotype distributions were similar between PBC patients and the general population. At the time of diagnosis, the 4 allele carriers were younger (P<0.05), had higher bilirubin (P<0.05) and IgG (P<0.001) levels and a lower prothrombin index (P<0.01) than 2 (homozygous+heterozygous) or 3 homozygous allele carriers. After 4-year UDCA therapy, the decrease in serum alkaline phosphatase and in alanine and aspartate aminotransferase activities was lower in percentage in the 4 than in other allele carriers (P<0.01). Conclusions: Although apo-E polymorphism does not appear to confer susceptibility to PBC, it probably influences PBC progression and response to UDCA. The 4 allele may identify patients with high risk of severe disease and poor response to treatment.