Background/aims: Primary biliary cirrhosis (PBC) is a chronic, cholestatic liver disease that progresses to liver cirrhosis. Patients who develop end-stage liver disease are candidates for
liver transplantation. Several studies have supported the view that ursodeoxycholic acid (UDCA) prolongs survival in PBC, but results have been challenged in other reports. Nevertheless, UDCA is currently recommended as standard therapy in PBC. The aims of this
study were to 1) evaluate the effect of UDCA on the clinical course in a Norwegian cohort of PBC patients and to 2) estimate cost-effectiveness of UDCA therapy in the perspective of
public health service.
Patients and methods: 180 Norwegian PBC patients (90% females; mean age 56.2 ± 8.9 years; Mayo risk score 4.38) were included in a five-year open-label study of UDCA therapy. The observed survival of the UDCA-treated patients was compared with survival predicted from the Mayo prognostic model for PBC and with survival (at four years) of the placebo group in a previous Canadian trial of UDCA in PBC (n = 111; 95% females; mean age 55.4 years; Mayo risk score 4.4). The frequencies of major events in the UDCA group were compared with those of the combined placebo groups in the Canadian trial and a previous study from the Mayo Clinic (n = 91; 87% females; Mayo risk score 5.2). The hospital costing model for Rikshospitalet University Hospital was applied to estimate average annual costs (2005 NOK) of major events. A spread sheet model was constructed for the calculations of costs. Cost-effectiveness was expressed as the ratio of incremental cost of UDCA therapy as compared with standard therapy, to the incremental gain in life expectancy during the four
years of study.
Results: The observed survival of the UDCA-treated patients was significantly higher than that of the control group (P < 0.001; log-rank test). Within the four-year perspective, the life expectancy was 3.92 years in patients on UDCA therapy and 3.54 years in those receiving standard treatment (discounted, 3.57 years and 3.22 years, respectively). The life expectancey of the UDCA-treated patients according to the Mayo prognostic model was 3.79 years (discounted 3.45 years). The net total discounted cost per patient of the UDCA strategy was NOK 73 000 as compared with NOK 302 000 of standard treatment. Thus, the incremental discounted cost of UDCA therapy as compared with standard therapy was minus NOK 229 000, and the incremental discounted gain in life expectancy was 0.35 years. One-way
sensitivity analysis revealed that even the upper bound cost estimate in the UDCA group (NOK 205 000) was slightly less that the lower bound estimate in the control group (NOK 210 000).
Conclusions: The results of this study indicate that UDCA therapy in PBC confers reduced morbidity, gain in life expectancy as well as cost savings comparedwith standard therapy and thus represents a dominant strategy.