Endocrine Abstracts

Introduction

Osteoporosis is a common disease characterised by a decrease in bone mass attributed to an imbalance between bone formation and resorption. Oral bisphosphonates have proven efficacy in increasing bone mineral density (BMD) and fracture reduction. Prior to the introduction of i.v. Ibandronate, patients who were unable to tolerate oral bisphosphonate were treated with i.v. Pamidronate (APD).

Aim

To assess BMD before and after intermittent IV Pamidronate and to determine the rate of fracture while on treatment.

Methods

A retrospective audit of 88 patients, (16 male and 72 female, age ranging from 21 to 88 years) with osteoporosis commencing i.v. APD between Dec 1999 and Oct 2005. 37.5% and 21.5% of patients were on oral steroid prior to and during treatment respectively. Patients were treated with 30-60 mg of APD i.v. every three-month. The main outcome measure was BMD shown by DEXA bone scan.

Results

The mean age, mean length of treatment and mean total APD dose were 69.8±11.1 years, 27.5±14.6 months and 566±310 mg respectively. Mean baseline Tscore at lumbar (L) 2–4 spine and femoral neck were −3.19±1.10 and −2.47±0.91, respectively. From baseline to after APD treatment, there was a significant increase in L2–4 BMD (0.828±0.144 vs 0.864±0.140 g/cm², P<0.001, mean increase +4.4%), in femoral neck BMD (0.688±0.111 vs 0.706±0.110 g/cm², P<0.001, mean increase +2.6%), The fracture incidence for vertebra and non-vertebra before iv APD were 27%&34% respectively and % of patients with fracture over the treatment period for vertebra and non-vertebra were 2.47%&3.96% per year respectively. Mild side effects occurred in eight patients.

Conclusion

Intravenous Pamidronate increases BMD and well tolerated by patients who cannot have oral bisphosphonates.