Effect of intravenous hydration in patients receiving bisphosphonate therapy

Background Patients with advanced cancers are at high risk for bone metastases, which accelerate bone resorption and skeletal complications. Therefore, bisphosphonates, which are strong inhibitors of bone resorption, are widely used to prevent pathological fractures, pain and tumour-induced hypercalcaemia. Intravenous infusion of bisphosphonate is associated with dose- and infusion rate-dependent adverse renal effects. Objective The present study investigated the effect of hydration on bisphosphonate efficacy and safety. Settings The 600-bed CHOV Hospital (Neufchâteau, France) and the Université de Lorraine (Nancy, France). Methods Patients who received pamidronate or zoledronic acid treatments were identified: 50 patients [16 of whom were hydrated and 34 of whom were non-hydrated]. Data on serum calcium levels, creatinine clearance and clinical tolerance were collected. Main outcome measure The impact of hydration on these parameters was analysed between day 1 and day 7. Results Bisphosphonate normalized calcaemia and hydration did not induce further reduction of calcium levels. Patient kidneys were significantly preserved by hydration in both groups (median clearance: +6.2 %), whereas dehydrated patients had lower creatinine clearance (median clearance: −1.1 %). Hydration did not influence other clinical or biological parameters tested. Conclusion Hydration plays an important role in the treatment of hypercalcaemia by pamidronate and zoledronic acid: it enhances kidney protection (i.e., creatinine clearance).