Bone disease in patients with primary sclerosing cholangitis: prevalence, severity and prediction of progression

Osteopenia is a common complication in some chronic cholestatic liver diseases. Our aims were to determine the prevalence and severity of bone disease in patients with primary sclerosing cholangitis; and identify risk factors to predict the presence and progression of osteopenia.

Eighty-one patients involved in a randomized trial of ursodeoxycholic acid were analyzed. Bone mineral density of the lumbar spine was determined at entry and at annual intervals.

Bone mineral density of the lumber spine in primary sclerosing cholangitis patients was significantly lower than expected when compared to normal values adjusted for age, sex and ethnic group at entry (p<0.005), and after 1 year (p<0.05), 2 years (p<0.05), 4 years (p<0.005) and 5 years of follow-up (p<0.005). Seven patients (8.6%) had bone mineral density of the lumber spine below the fracture threshold at entry. These patients were significantly older, had a longer duration of inflammatory bowel disease and more advanced primary sclerosing cholangitis. The rate of bone loss in primary sclerosing cholangitis patients and expected in normal controls was 0.01+/-0.02 g x cm(-2) x year(-1) and 0.003+/-0.003 g x cm(-2) x year(-1), respectively (p = NS), and was similar in patients receiving placebo and ursodeoxycholic acid. Age was the only variable inversely related with baseline bone mineral density of the lumber spine (p<0.0001). None of the variables predicted progression of the bone disease.

Severe osteoporosis occurs in few patients with primary sclerosing cholangitis, but it should be suspected in patients with longer duration of inflammatory bowel disease and more advanced liver disease. Its presence, severity and progression cannot be accurately evaluated by routine clinical, biochemical, or histological variables. Ursodeoxycholic acid does not affect the rate of bone loss in primary sclerosing cholangitis.