Alendronate use in older patients with reduced renal function: challenges and opportunities in clinical practice.

In this retrospective cohort study, alendronate use among older osteoporosis patients (age>65 years) with reduced renal function (creatinine clearance<35ml/min) was not associated with significant deterioration in renal function from baseline nor increased incidence of osteoporotic fractures or acute kidney injury, compared with patients conservatively managed with only calcium/vitamin D supplementation. INTRODUCTION: Oral bisphosphonates are not recommended in patients with creatinine clearance (CrCl) <35ml/min, although this is not supported by post hoc analyses of pivotal oral bisphosphonate studies. As both osteoporosis and renal insufficiency are more prevalent with advancing age, it is important to determine the safety and efficacy of oral bisphosphonates among these patients. METHODS: Patients with CrCl <35ml/min on alendronate (group A, n=98), with CrCl <35ml/min conservatively managed (group B, n=96), and with CrCl ≥35ml/min on alendronate (group C, n=96) were followed up to 22 months. Primary outcomes were mean change in CrCl from baseline in group A compared with groups B and C, respectively. Secondary outcomes were the incidence of osteoporotic fractures and adverse events between groups. RESULTS: There was no significant change in CrCl from baseline when comparing group A (-1.53±6.83ml/min) with group B (0.59±5.17ml/min) (p=0.075), and group A with group C (-3.71±7.54ml/min) (p=0.163). There was no significant increase in incidences of osteoporotic fractures in group A compared with group B (adjusted relative risk (aRR) 2.02, 95% confidence interval (CI) 0.64-6.37) and group A compared with group C (aRR 1.15, 95% CI 0.46-2.89). There was no significant difference in incidences of acute kidney injury (AKI) in group A compared with group B (aRR 0.48, 95% CI 0.20-1.12). Although statistically non-significant, there was an increase in AKI incidence in group A compared with group C (RR 7.84, 95% CI 0.98-62.66). CONCLUSION: Among patients with CrCl <35ml/min, alendronate therapy was not associated with significant deterioration in renal function from baseline. Although not powered for secondary outcomes, there were no statistically significant differences in osteoporotic fracture or AKI incidence between the groups.

Factors leading to blood transfusion among Chinese patients undergoing total knee replacements: a retrospective study.

PURPOSE: To investigate the risk factors leading to blood transfusion among Chinese patients undergoing total knee replacement. METHODS: From July 2001 to June 2002, a total of 128 primary total knee replacements were performed in 83 Chinese patients (38 unilateral and 45 one-stage sequential bilateral). No pharmaceutical prophylaxis against deep vein thrombosis was used. The risk factors leading to allogenic blood transfusion were analysed. RESULTS: The important predictive factors for postoperative blood transfusion were preoperative haemoglobin level (p=0.005), intra-operative blood loss (p<0.001), and bilateral total knee replacements (p<0.001). CONCLUSION: To reduce the need of allogenic blood transfusion, we suggest administering erythropoietin or iron supplements to increase the haemoglobin level for patients undergoing total knee replacement. Routine use of intra-operative blood salvage can be considered for patients undergoing one-stage bilateral total knee replacement. Use of a postoperative blood salvage system is recommended for surgeries that may result in major intra-operative blood loss.