Osteoporosis screening in an outpatient liver transplant clinic: impact of primary immunosuppression

Effects of alendronate on bone mineral density and bone metabolic markers in patients with liver transplantation

INTRODUCTION

The purpose of this study was to evaluate the effects of alendronate (ALN) on bone mineral density (BMD) and bone turnover markers in patients with orthotopic liver transplantation (OLT).

METHODS

In the prospective, controlled, open study with 24 months of follow-up, 98 patients with OLT were randomised to receive ALN 70 mg weekly or no ALN; calcium (Ca) 1,000 mg daily and 0.5 mcg calcitriol daily were provided to all patients. Lumbar spine (LS) and hip BMDs were measured at 6-month intervals by dual-energy X-ray absorptiometry (DEXA). Spinal radiographs were obtained to assess vertebral fractures. Additionally, bone turnover markers, serum parathyroid hormone (PTH) and biochemical parameters were determined every 3 months.

RESULTS

Compared with the control group, the ALN group showed significant increases in BMD of the LS (5.1+/-3.9% vs 0.4+/-4.2%, p<0.05 at 12 months, 8.9+/-5.7% vs 1.4+/-4.9%, p<0.05 at 24 months), femoral neck (4.3+/-3.8% vs -1.1+/-3.1%, p<0.05 at 12 months, 8.7+/-4.8% vs 0.6+/-4.5%, p<0.05 at 24 months) and total femur (3.6+/-3.8% vs -0.6+/-4.0%, p<0.05 at 12 months, 6.2+/-3.8% vs 0.3+/-4.6%, p<0.05 at 24 months). In the ALN group, osteocalcin and urinary deoxypyridinoline (DPD) decreased significantly at the sixth month, with no further change, by -35.6% and -63.0%, on average, respectively (p<0.05). In the control group, a significant increase in biochemical markers of bone turnover was observed in comparison to baseline values (p<0.05). PTH increased within reference levels without a difference between groups. Two nonvertebral fractures (4.2%) and nine vertebral fractures (18.8%) in the control group and three vertebral fractures (6.8%) in the ALN group occurred during the follow-up. The weekly ALN was well tolerated, and no severe side effects occurred.

CONCLUSION

This is the first randomised study including a control group to demonstrate that weekly ALN was able to significantly increase BMD in patients with OLT when compared with Ca and calcitriol alone. However, ALN did not appear to offer protection against fractures.

Alendronate in combination with calcium and vitamin D prevents bone loss after orthotopic liver transplantation: a prospective single-center study

Bone loss is a common complication in patients before and after liver transplantation (LT). The aim of this study was to investigate the efficacy of prophylactic treatment with bisphosphonates after LT in preventing progressive bone loss in LT patients. We included 136 patients with end-stage liver diseases awaiting LT. Bone mineral density (BMD) (by dual X-ray absorptiometry) and markers of bone metabolism were determined before, and 4, 12, 24, 36, and 48 months after LT. All patients received vitamin D and calcium supplementation before and after LT, those with osteopenia or osteoporosis prior to LT were additionally treated with alendronate following LT. Decreased BMD was seen in a high percentage of patients undergoing LT (osteopenia 48.5%, osteoporosis 23.5%). Reduced BMD before LT was not related to gender, underlying liver disease, or Child-Turcotte-Pugh classification. Body mass index (BMI) prior to LT, however, correlated significantly with the fracture risk. Alendronate prevented the ubiquitously observed bone loss after LT in patients with osteoporosis and osteopenia and, in addition, led to an increase in BMD in patients with osteoporosis within 24 months after LT. In conclusion, our study suggests that alendronate is efficacious in preventing the natural course of bone loss associated with LT.

Older age and liver transplantation: a review

Patients older than 60 are undergoing transplantation with increasing frequency. Reports from several transplant centers document that overall short-term patient survival rates in seniors undergoing liver transplantation are comparable to survival rates of younger adults. However, specific subgroups of older patients may not fare as well. Seniors with far-advanced end-stage liver disease are high-risk for liver transplantation and have poor survival rates. In addition, seniors older than 65 have worse outcomes than those who are 60 to 65, and studies have shown increased mortality with increasing age as a continuous variable. On the other hand, the majority of seniors who survive liver transplantation have full or only minimally limited functional status. Preoperative evaluation of older patients for transplantation requires careful screening to exclude cardiopulmonary disease, malignancy, and other diseases of the aged. Paradoxically, seniors may benefit from a senescent immune system, which results in decreased requirements for immunosuppressive drugs, and possibly a lower rate of acute allograft rejection. Despite good overall short-term survival in the elderly, long-term survival may be worse because of an increased rate of long-term complications, such as malignancy and heart disease. In conclusion, although advanced age is a negative risk factor, advanced age alone should not exclude a patient from liver transplantation; however, it mandates thorough pretransplant evaluation and careful long-term follow-up with attention to usual health maintenance issues in the elderly.