The impact of pamidronate on inpatient and outpatient services among metastatic breast cancer patients.

Our goal was to evaluate the impact of pamidronate therapy on medical resource utilization for treatment of bone metastases among patients with breast cancer. In this 12-center retrospective study, inpatient and outpatient resource utilization was abstracted from the medical charts of 295 patients with breast cancer who were diagnosed with bone metastases between July 1996 and April 1999. Data were abstracted from the time of bone metastasis diagnosis (baseline) to the present. The analysis compared non-pamidronate patients against pamidronate patients, who were stratified on the basis of whether their pamidronate therapy had been initiated within 3 months (early pamidronate group) or more than 3 months (late pamidronate group) after diagnosis. Resource utilization was compared among groups using multivariate regression analyses. A total of 101 early pamidronate, 72 late pamidronate, and 122 non-pamidronate patients were included in the analysis. The results showed that the early pamidronate group was roughly one-half as likely to have unplanned office visits attributable to bone metastases as the late pamidronate and non-pamidronate groups. The groups had a similar likelihood of ever being hospitalized for bone-related conditions; however, among those hospitalized, there were roughly one-half as many bone-related hospitalizations in the late pamidronate group as in the non-pamidronate group. Also, the mean length of stay was approximately 50% shorter in both pamidronate groups than in the non-pamidronate group. We conclude that pamidronate therapy may be associated with less medical resource utilization, particularly among patients hospitalized for bone-related conditions.