Many patients who undergo hematopoietic cell transplantation experience liver injury.
Dr McDonald and colleagues examined the association of serum bilirubin levels with nonrelapse mortality by day +200.
The research team tested the hypothesis that the duration of jaundice up to a given point in time provides more prognostic information than either the maximum bilirubin value or the value at that point in time.
The researchers studied a total of 1,419 consecutive patients transplanted from allogeneic donors.
Using Cox regression models with each bilirubin measure modeled as a time-dependent covariate, the research team recorded total serum bilirubin values up to day +100, death, or relapse.
In addition, they noted nonrelapse mortality by day +200 as an outcome measure.
The bilirubin value at a particular point in time provided the best fit to the model for mortality.
|Survival was related to the absence of multiorgan failure and to higher platelet counts|
The researchers found that, with bilirubin at a point in time modeled as an 8th-degree polynomial, an increase in bilirubin from 1 to 3 mg/dL is associated with a mortality hazard ratio of 6.42.
The research team noted that an increase from 4 to 6 mg/dL yields a hazard ratio of 2.05, and an increase from 10 to 12 mg/dL yields a hazard ratio of 1.17.
Among patients who were deeply jaundiced, survival was related to the absence of multiorgan failure and to higher platelet counts.
Dr McDonald concluded, "The value of total serum bilirubin at a particular point in time after transplant carries more informative prognostic information than does the maximum or average value up to that point in time."
"The increase in mortality for a given increase in bilirubin value is larger when the starting value is lower."