J Urol. 2009 Nov;182(5):2257-64. Epub 2009 Sep 16.
zoledronic acid to prevent osteoporosis in a veteran population with
multiple risk factors for bone loss on androgen deprivation therapy.
Bhoopalam N, Campbell SC, Moritz T, Broderick WR, Iyer P, Arcenas AG, Van Veldhuizen PJ, Friedman N, Reda D, Warren S, Garewal H.
Edward Hines, Jr Veterans Affairs Hospital, Hines, Illinois 60141, USA.
Androgen deprivation therapy for prostate cancer is associated with
osteoporosis and increased fracture risk. Previous studies of
zoledronic acid demonstrated bone loss prevention in patients
initiating androgen deprivation therapy. There are limited data on
patients on prolonged androgen deprivation therapy or in Veterans
Affairs patients with multiple risk factors for osteoporosis.
We randomized 93 patients with M0 prostate cancer in this placebo
controlled trial in the Veterans Affairs health care system. Preplanned
strata included 50 patients on androgen deprivation therapy for less
than 1 year (stratum 1) and 43 on androgen deprivation therapy for
greater than 1 year (stratum 2). In each stratum patients were
randomized to 4 mg zoledronic acid intravenously every 3 months for 4
treatments or intravenous placebo. The primary end point was the
percent change in bone mineral density at the lumbar spine at 12
months. RESULTS: Age, race, body mass index and osteoporosis risk
factors were similar for the 2 treatments. Most patients were former
smokers, had moderate alcohol intake, were not on calcium/vitamin D
supplements and were relatively sedentary at baseline. In stratum 1
spine bone mineral density increased 5.95% in the zoledronic acid arm
and decreased 3.23% in the placebo arm (p = 0.0044). In stratum 2 spine
bone mineral density increased 6.08% in the zoledronic acid arm and
only increased 1.57% in the placebo arm (p = 0.0005). Treatment was
well tolerated with minimal impact on renal function.
Zoledronic acid improved bone mineral density in patients with M0
prostate cancer on androgen deprivation therapy for 1 year or less, or
greater than 1 year. This finding indicates that bisphosphonate therapy
remains effective when initiated later in the course of androgen
deprivation therapy and is efficacious in Veterans Affairs patients
with multiple risk factors for osteoporosis.