Assessment of Prognosis with the Total Illness Burden Index for Prostate Cancer
Aiding Clinicians in Treatment Choice
Published in: Cancer, v. 109, no. 9, May 1, 2007, p. 1777-1783
Posted on RAND.org on December 31, 2006
BACKGROUND: Among the most pressing challenges that face physicians who care for men with prostate cancer is evaluating the patient's potential for benefiting from treatment. Because prostate cancer often follows an indolent course, the presence and severity of comorbidities may influence the decision to treat the patient aggressively. The authors adapted the Total Illness Burden Index (TIBI) for use in decision-making among men with prostate cancer at the time of the visit. METHODS: An observational study was performed of 2894 participants in the Cancer of the Prostate Strategic Urologic Research Endeavor, a national disease registry of men with prostate cancer, to examine how well the adapted TIBI for prostate cancer (TIBI-CaP) predicted mortality over the subsequent 3.5 years and health-related quality of life over the subsequent 6 months. RESULTS: The men who had the highest global TIBI-CaP scores were 13 times more likely to die of causes other than prostate cancer over a 3.5-year period than the men who had the lowest scores (hazard ratio, 13.1, 95% confidence interval, 6.3-27.4) after controlling for age, education, income, and race/ethnicity. Patients who had the highest TIBI-CaP scores had 44% mortality compared with 4.9% mortality for patients who had the lowest scores. Demographic variables explained 16% of the variance in future physical function; TIBI-CaP scores explained an additional 19% of the variance. CONCLUSIONS: The TIBI-CaP, a patient-reported measure of comorbidity, identified patients at high risk for nonprostate cancer mortality. It predicted both mortality and future quality of life. The TIBI-CaP may aid physicians and patients in making appropriate treatment decisions.