Christensen et al developed a prognostic model for patients with primary biliary cirrhosis (PBC). The authors are from Hvidovre Hospital Copenhagen, King's College Hospital, Mount Sinai Medical School, Middlesex Hospital and the Danish Medical and Social Science Research Councils.
Patient selection: primary biliary cirrhosis
Parameters:
(1) serum total bilirubin in µmol/L
(2) age in years
(3) serum albumin in g/L
(4) cirrhosis
(5) central cholestasis
(6) therapy
points for bilirubin =
= LOG10(bilirubin)
points for age =
= EXP(((age in years) - 20) / 10)
Parameter
Finding
Points
cirrhosis
absent
0
present
1
central cholestasis
absent
0
present
1
therapy
azathioprine
0
placebo
1
prognostic index =
= (2.51 * (points for bilirubin)) + (0.0069 * (points for age)) - (0.05 * (serum albumin)) + (0.88 * (points for cirrhosis)) + (0.68 * (points for central cholestasis)) + (0.52 * (points for therapy))
Interpretation:
• In the study the prognostic index ranged from -1 to 8.
• The higher the score the worse the survival time in years. Survival was less than 1 year when the score was > 6.
