THE ECONOMIC BURDEN OF METASTATIC AND PROSTATE SPECIFIC ANTIGEN PROGRESSION IN PATIENTS WITH PROSTATE CANCER: FINDINGS FROM A RETROSPECTIVE ANALYSIS OF HEALTH PLAN DATA

Abstract

We evaluated the economic burden of metastatic and prostate specific antigen (PSA) progression in patients with prostate cancer (CaP) using a cancer registry linked administrative database. A retrospective cohort evaluation of 2056 patients with CaP was done at Henry Ford Health System from 1995 to 2000. Records were examined for metastatic progression via International Classification of Disease-9-CM codes for metastasis and for PSA progression using accepted definitions based on initial therapy type. Health care resource charges 6 months and 1 year before and after progression were compared using pairwise t tests. A generalized linear model determined the effect of progression on charges and compared initial care, continuing care and terminal care charges in the progressed and nonprogressed groups, while controlling for baseline covariates (stage and age). Patients with CaP had a mean age of 68 years, were mostly white (52%), had localized (88%) and moderately differentiated (66%) tumors, and a median baseline PSA of 7.0 ng/ml. Of patients 8.9% had metastatic progression at a mean followup of 3.6 years, while 16.1% had PSA progression at 4.5 years. After controlling for baseline covariates metastatic progression resulted in significant increases in charges (US dollars 92523 vs US dollars 58036, p < 0.0001). PSA progressed patients incurred significantly higher charges than nonprogressed patients (US dollars 69321 vs US dollars 58351, p = 0.0039), controlling for followup time, baseline stage, grade and treatment. In CaP cases metastatic and PSA progression pose a significant economic burden irrespective of baseline stage, grade and treatment. Treatments that slows or prevents meta-static and PSA progression could offset this cost.