Pamidronate and osteoporosis prevention in liver transplant recipients

Increased Imminent Fracture Risk in Liver Transplant Recipients Despite Bisphosphonate Therapy

BACKGROUND

Bone loss is significant after orthotopic liver transplant (OLT) and is associated with increased fracture risk and decreased quality of life. In post-transplant fracture prevention, the cornerstone of therapeutic management is bisphosphonates.

METHODS

We conducted a retrospective study in a cohort of 155 OLT recipients who received a bisphosphonate prescription at hospital discharge between 2012 and 2016 to investigate post-OLT fragility fracture incidence and predictive risk factors.

RESULTS

Before OLT, 14 patients presented a T score < -2.5 SD, and 23 patients (14.8%) had a history of fracture. During follow-up, the cumulative incidence of fractures on bisphosphonates (99.4% risedronate/alendronate) was 9.7% at 12 months and 13.1% at 24 months. The median time to first fragility fracture was 10 months (IQR, 3-22 months) and thus within the first 2 years of follow-up. Predictive factors of fragility fractures in multivariate Cox regression analyses included age 60 years or older (hazard ratio [HR], 2.61; 95% CI, 1.14-6.01; P = .02), post-transplant diabetes mellitus (HR, 3.82; 95% CI, 1.55-9.44; P = .004), and cholestatic disease (HR, 5.93; 95% CI, 2.30-15.26; P = .0002). Additionally, the female sex was associated with a strong trend toward increased fracture risk in univariate analysis (HR, 2.27; 95% CI, 1.00-5.15; P = .05), as well as a post-transplant absolute decrease in bone mineral density at the femoral neck and total hip (P = .08).

CONCLUSIONS

This real-world study reports a high incidence of fractures post-OLT despite bisphosphonate therapy. Age 60 years or older, post-transplant diabetes mellitus, cholestatic disease, female sex, and femoral neck and/or total hip bone mineral density loss contribute to increased imminent fracture risk in liver transplant recipients.

Main factors influencing long-term outcomes of liver transplantation in 2022

Liver transplant (LT) outcomes have markedly improved in the recent decades, even if long-term morbidity and mortality are still considerable. Most of late deaths are independent from graft function and different comorbidities, including complications of metabolic syndrome and de novo neoplasms, seem to play a key role in determining long-term outcomes in LT recipients. This review discusses the main factors associated with late mortality and suggests possible strategies to improve long-term management and follow-up after liver transplantation. In particular, the reduction of drug toxicity, the use of tools to identify high-risk patients, and setting up a multidisciplinary team also for long-term management of LT recipients may further improve survival after liver transplantation.

Bisphosphonate therapy after liver transplant improves bone mineral density and reduces fracture rates: an updated systematic review and meta-analysis

To investigate the efficacy of bisphosphonates and compare oral and IV formulations on bone mineral density (BMD) and fracture incidence in post-orthotopic liver transplant (OLT) patients. Electronic databases were searched, and six RCTs and three cohort studies were included out of 711 articles. Main outcomes included post-OLT BMD changes, fracture incidence, and treatment adverse reactions. Pairwise meta-analysis was conducted for binary and continuous outcomes, while pooled fracture incidence utilized single-arm meta-analysis. Post-OLT fracture incidence was reported in nine studies (n = 591). Total fracture incidence was 6.6% (CI: 3.4-12.4%) in bisphosphonate group and 19.1% (CI: 14.3-25.1%) in calcium and vitamin D group. Total fractures were significantly lower in patients on bisphosphonate, compared to calcium and vitamin D (n = 591; OR = 0.037; CI: 0.18-0.77; P = 0.008). Overall fractures were significantly lower in the oral group (n = 263; OR = 0.26; CI: 0.08-0.85; P = 0.02) but not in the IV group (n = 328; OR = 0.45; CI: 0.16-1.26; P = 0.129). Both oral and IV bisphosphonates are effective in reducing fracture incidence post-OLT compared to calcium and vitamin D. Oral formulations may also have an advantage over IV in reducing bone loss and fracture incidence post-OLT.

Glucocorticoid- and Transplantation-Induced Osteoporosis

Glucocorticoid-induced osteoporosis is the most common cause of secondary osteoporosis; nonetheless, it remains an undertreated condition. Transplantation-induced osteoporosis encompasses a broad range of unique pathogenetic features with distinct characteristics dependent on the transplanted organ. Understanding the pathogenesis of bone loss is key to recommending osteoporosis therapy in these patients. This review summarizes recent advances and addresses current issues in these fields.

Cystic fibrosis bone disease treatment: Current knowledge and future directions

Bone disease is a frequent complication in adolescents and adults with cystic fibrosis (CF). Early detection and monitoring of bone mineral density and multidisciplinary preventive care are necessary from childhood through adolescence to minimize CF-related bone disease (CFBD) in adult CF patients. Approaches to optimizing bone health include ensuring adequate nutrition, particularly intake of calcium and vitamins D and K, addressing other secondary causes of low bone density such as hypogonadism, encouraging weight bearing exercise, and avoiding bone toxic medications. Of the currently available anti-resorptive or anabolic osteoporosis medications, only bisphosphonates have been studied in individuals with CF. Future studies are needed to better understand the optimal approach for managing CFBD.

Bone Health in Patients With Liver Diseases

Osteoporosis is the most common bone disease in chronic liver disease (CLD) resulting in frequent fractures and leading to significant morbidity in this population. In addition to patients with cirrhosis and chronic cholestasis, patients with CLD from other etiologies may be affected in the absence of cirrhosis. The mechanism of osteoporosis in CLD varies according to etiology, but in cirrhosis and cholestatic liver disease it is driven primarily by decreased bone formation, which differs from the increased bone resorption seen in postmenopausal osteoporosis. Direct toxic effects from iron and alcohol play a role in hemochromatosis and alcoholic liver disease, respectively. Chronic inflammation also has been proposed to mediate bone disease in viral hepatitis and nonalcoholic fatty liver disease. Treatment trials specific to osteoporosis in CLD are small, confined to primary biliary cholangitis and post-transplant patients, and have not consistently demonstrated a benefit in this population. As it stands, prevention of osteoporosis in CLD relies on the mitigation of risk factors such as smoking and alcohol use, treatment of underlying hypogonadism, and encouraging a healthy diet and weight-bearing exercise. The primary medical intervention for the treatment of osteoporosis in CLD remains bisphosphonates though a benefit in terms of fracture reduction has never been shown. This review outlines what is known regarding the pathogenesis of bone disease in CLD and summarizes current and emerging therapies.

Bone disease following solid organ transplantation: A narrative review and recommendations for management from The European Calcified Tissue Society

INTRODUCTION

Solid organ transplantation is an established therapy for end-stage organ failure. Both pre-transplantation bone disease and immunosuppressive regimens result in rapid bone loss and increased fracture rates.

METHODS

The European Calcified Tissue Society (ECTS) formed a working group to perform a systematic review of existing literature on the consequences of end-stage kidney, liver, heart, and lung disease on bone health. Moreover, we assessed the characteristics of post-transplant bone disease and the skeletal effects of immunosuppressive agents and aimed to provide recommendations for the prevention and treatment of transplantation-related osteoporosis.

RESULTS

Characteristics of bone disease may differ depending on the organ that fails, but patients awaiting solid organ transplantation frequently depict a wide spectrum of bone and mineral abnormalities. Common features are a decreased bone mass and impaired bone strength with consequent high fracture risk, all of which are aggravated in the early post-transplantation period.

CONCLUSION

Both the underlying disease leading to end-stage organ failure and the immunosuppression regimens implemented after successful organ transplantation have detrimental effects on bone mass, quality and strength. Given existing ample data confirming the high frequency of bone disease in patients awaiting solid organ transplantation, we recommend that all transplant candidates should be assessed for osteoporosis and fracture risk and, if indicated, treated before and after transplantation. Since bone loss in the early post-transplantation period occurs in virtually all solid organ recipients and is associated with glucocorticoid administration, the goal should be to use the lowest possible dose and to taper and withdraw glucocorticoids as early as possible.

Low bone density and fractures before and after pediatric lung transplantation

INTRODUCTION

Children undergoing lung transplant are at risk for low bone mineral density (BMD) and fractures. The effect of lung transplantation on bone health in pediatric patients is unknown.

MATERIALS AND METHODS

We performed a retrospective chart review of all patients ages 2-21 years who underwent lung transplantation at our hospital from January 2000 to January 2015.

RESULTS

51 patients were studied. At the time of transplant evaluation, BMD Z-score was -2.2 ± 1.4, and 59% of patients had low BMD. BMD Z-score declined in the first year after treatment and returned to near-baseline by the third post-transplant year. Fractures occurred in 9 patients (18%) before and 15 patients (29%) after transplant. Bisphosphonate use was associated with improvement in BMD Z-score and lower mortality risk.

CONCLUSIONS

Pediatric patients had a high prevalence of low BMD at the time of lung transplant evaluation. BMD Z-scores declined in the year after transplant and returned to the pre-transplant level by the third post-transplant year while remaining below normal levels. Fractures were common at sites associated with significant morbidity. These findings support efforts to optimize bone health before and after pediatric lung transplantation, and future studies are needed to evaluate the role of bisphosphonates in these patients.

Osteoporosis in chronic liver disease

Osteoporosis is a frequent complication in patients with chronic liver disease, especially in end-stages and in chronic cholestasis, in addition to non-alcoholic fatty liver disease, haemochromatosis and alcoholism. Mechanisms underlying osteoporosis are poorly understood, but osteoporosis mainly results from low bone formation. In this setting, sclerostin, a key regulator of the Wnt/β-catenin signalling pathway which regulates bone formation, in addition to the effects of the retained substances of cholestasis such as bilirubin and bile acids on osteoblastic cells, may influence the decreased bone formation in chronic cholestasis. Similarly, the damaging effects of iron and alcohol on osteoblastic cells may partially explain bone disease in haemochromatosis and alcoholism. A role for proinflammatory cytokines has been proposed in different conditions. Increased bone resorption may occur in cholestatic women with advanced disease. Low vitamin D, poor nutrition and hypogonadism, may be contributing factors to the full picture of bone disorders in chronic liver disease.

Diagnosis and Management of Cirrhosis-Related Osteoporosis

Management of cirrhosis complications has greatly improved, increasing survival and quality of life of the patients. Despite that, some of these complications are still overlooked and scarcely treated, particularly those that are not related to the liver. This is the case of osteoporosis, the only cirrhosis complication that is not solved after liver transplantation, because bone loss often increases after immunosuppressant therapy. In this review, the definitions of bone conditions in cirrhotic patients are analyzed, focusing on the more common ones and on those that have the largest impact on this population. Risk factors, physiopathology, diagnosis, screening strategies, and treatment of osteoporosis in cirrhotic patients are discussed, presenting the more striking data on this issue. Therapies used for particular conditions, such as primary biliary cirrhosis and liver transplantation, are also presented.

Metabolic consequences of modern immunosuppressive agents in solid organ transplantation

Among other factors, sophistication of immunosuppressive (IS) regimen accounts for the remarkable success attained in the short- and medium-term solid organ transplant (SOT) survival. The use of steroids, mycophenolate mofetil and calcineurin inhibitors (CNI) have led to annual renal graft survival rates exceeding 90% in the last six decades. On the other hand, attrition rates of the allograft beyond the first year have remained unchanged. In addition, there is a persistent high cardiovascular (CV) mortality rate among transplant recipients with functioning grafts. These shortcomings are in part due to the metabolic effects of steroids, CNI and sirolimus (SRL), all of which are implicated in hypertension, new onset diabetes after transplant (NODAT), and dyslipidemia. In a bid to reduce the required amount of harmful maintenance agents, T-cell-depleting antibodies are increasingly used for induction therapy. The downsides to their use are greater incidence of opportunistic viral infections and malignancy. On the other hand, inadequate immunosuppression causes recurrent rejection episodes and therefore early-onset chronic allograft dysfunction. In addition to the adverse metabolic effects of the steroid rescue needed in these settings, the generated proinflammatory milieu may promote accelerated atherosclerotic disorders, thus setting up a vicious cycle. The recent availability of newer agent, belatacept holds a promise in reducing the incidence of metabolic disorders and hopefully its long-term CV consequences. Although therapeutic drug monitoring as applied to CNI may be helpful, pharmacodynamic tools are needed to promote a customized selection of IS agents that offer the most benefit to an individual without jeopardizing the allograft survival.

Keys to long-term care of the liver transplant recipient

Improvements in overall survival early after liver transplantation result in a growing number of patients with the potential for long-term survival. Data available on long-term survival, to date, reflect the situation of patients who received their liver transplant during a very different health-care era. Translating these data into the current medical era of liver transplantation is an important task, as a better understanding of aspects associated with morbidity and mortality is fundamental in improving the long-term outcome of liver transplant recipients. Malignancy screening, optimal treatment of recurrent disease and adequate management of metabolic disease are crucial contributions to advance patient care. In this Review, data specific to the liver transplant recipient will be evaluated and, in the absence of sufficient evidence at this time, recommendations and guidelines for the general population on management of long-term concerns will be assessed for their applicability after liver transplantation. In addition, other preventive strategies relating to pregnancy, contraception and vaccination are reviewed in detail.

Osteoporosis after transplantation

Transplantation is an established therapy for end-stage diseases of kidney, lung, liver, and heart among others. Osteoporosis and fragility fractures are serious complications of organ transplantation, particularly in the first post-transplant year. Many factors contribute to the pathogenesis of osteoporosis following organ transplantation. This review addresses the mechanisms of bone loss that occurs both in the early and late post-transplant periods, including the contribution of the immunosuppressive agents as well as the specific features to bone loss after kidney, lung, liver, cardiac, and bone marrow transplantation. Prevention and treatment for osteoporosis in the transplant recipient are also discussed.

Post-transplantation osteoporosis

Transplantation is an established therapy for many hematologic disorders as well as for end-stage diseases of the kidney, lung, liver, heart among others. Osteoporosis and a high incidence of fragility fractures have emerged as a complication of organ transplantation. Many factors contribute to the pathogenesis of osteoporosis following organ transplantation. In addition, most patients have some form of bone disease prior to transplantation, which is usually related to adverse effects of end-stage organ failure on the skeleton. This chapter reviews the mechanisms of bone loss that occur both in the early and late post-transplant periods including the contribution of immunosuppressive agents as well as the specific features of bone loss after kidney, lung, liver, cardiac and bone marrow transplantation. Prevention and treatment for osteoporosis in the transplant recipient will also be addressed.

Effects of intravenous pamidronate on renal function, bone mineral metabolism and bone mass in patients with severe osteoporosis

INTRODUCTION

To analyze the effects of intravenous pamidronate (APD) on bone remodelling, bone mineral density (BMD), fractures and bone mineral metabolism parameters, and the rate of adverse events, with special attention to renal function, in patients with osteoporosis with intolerance and/or any contraindication to oral bisphosphonates.

METHODS

We analyzed prospectively 17 osteoporotic patients (age, 66.8 +/- 9.4 years): 65% women, 82% with prevalent vertebral fractures. All patients received APD therapy (30 mg intravenously every 3 months) and were followed up for 1 year. We analyzed serum amino-terminal propeptide of type I procollagen and urinary N-terminal cross-linked telopeptide of type I collagen (as markers of bone turnover), serum calcium, phosphate, parathormone, 25OH-vitamin D, creatinine, and the creatinine clearance: at baseline, 1 week after starting APD treatment, and thereafter for every 3 months (before infusion) during 1 year. We also analyzed lumbar and femoral BMD at baseline and after 1 year, the incidence of new fractures, and the treatment-related adverse events.

RESULTS

One week after starting APD treatment, a significant decrease of N-terminal cross-linked telopeptide of type I collagen (32%) (P < 0.05) and an increase of parathormone values (72%) (P < 0.01) were observed, without significant differences found thereafter. No significant differences were observed in BMD evolution and in the other parameters analyzed throughout the study, nor in impairment of renal function. Sixty-four percent of patients suffered new skeletal fractures, 41% of patients showed flu-like syndrome after APD infusion, and 1 patient was withdrawn from treatment because of adverse events.

CONCLUSION

Patients with severe osteoporosis receiving APD infusions had a high rate of fractures without significant changes in bone mass or in bone markers; nevertheless, such a therapeutic regimen showed a good renal safety profile, suggesting that APD at this dosage is safe but ineffective for treating severe osteoporosis.

Treatment of osteoporosis after liver transplantation with ibandronate

Osteoporosis is a major side-effect after liver transplantation (LTX). Therefore, the objective of the study was to evaluate the efficacy of ibandronate to reduce fractures after LTX. Seventy-four patients after LTX were included in the study and measurements of bone mineral density (BMD) of lumbar spine and proximal femur using dual energy X-ray absorptiometry (DEXA) were performed prior to and 3, 6, 12 and 24 months after surgery. The study group (IBA) consisted of 34 patients who received calcium (1 g/day), vitamin D3 (800-1000 IE/day) and ibandronate 2 mg every 3 months intravenously for 1 year. The control group consisted of 40 patients (CON) who received calcium and vitamin D3 at the same dosages. Prevalence of new fractures was predefined as primary endpoint. Changes of BMD and biochemical markers of bone metabolism were also investigated. In all patients, we found a reduction of BMD in the first few months after LTX. In the lumbar spine and the proximal femur the maximum reduction occurred 3 and 6 months post-LTX. One and 2 years after transplantation, the group receiving ibandronate demonstrated a better recovery from loss of BMD and a significantly lower prevalence of fractures (IBA 2 vs. CON 10 P < 0.04, chi(2)). Ibandronate with calcium and vitamin D3 reduces the BMD-loss after LTX and decreases the rate of bone fractures significantly.

Effect of bisphosphonates on bone mineral density in liver transplant patients: a meta-analysis and systematic review of randomized controlled trials

SUMMARY

Bone mineral density (BMD) loss after liver transplantation (LT) results in considerable morbidity with the increased risk of fractures. Data on the efficacy of bisphosphonate use in post LT patients is scarce. This meta-analysis aims to summarize the results from published randomized controlled trials (RCTs) on the topic of interest. Electronic databases were searched to identify relevant publications. A total of 157 articles were identified and reviewed. Individual authors were contacted from relevant RCTs to obtain individual patient data where necessary to uniformly quantify BMD values post LT pre- and post LT. A total of six RCTs were used for final data extraction. (i) Lumbar Spine: In 364 patients (six studies, 182 in intervention and control groups each), bisphosphonate therapy improved BMD by 0.03 g/cm(2) (95% C.I. 0.01-0.05 g/cm(2); P = 0.02) at 12 months post LT. (ii) Femoral neck: In 268 patients (four studies, 130 bisphosphonate, 138 control), bisphosphonate use did not result in a statistically significant change in BMD at the end of 1 year. None of the studies noted serious adverse effects related to bisphosphonate administration. Data on incident fractures could not be pooled because of heterogeneity. Bisphosphonate therapy during the first year in LT recipients appears to reduce accelerated bone loss and improve bone mineral density at the lumbar spine.

Approach to the patient with transplantation-related bone loss

Transplantation is an established therapy for end-stage diseases of the kidney, endocrine pancreas, heart, liver, lung, intestines and for many hematological disorders. Current immunosuppressive regimens with glucocorticoids and calcineurin inhibitors produce excellent patient and graft survival rates. This has resulted in both increases in transplant numbers and an increased recognition of previously neglected long-term complications of transplantation such as fractures and osteoporosis. Both pretransplantation bone disease and immunosuppressive therapy result in rapid bone loss and increased fracture rates. Patients are particularly at risk early after transplantation. The bone health of candidates for organ transplantation should be assessed with bone densitometry of the hip and spine. Spinal x-rays should be performed to diagnose prevalent fractures. Any secondary causes of osteoporosis should be identified and treated. Vitamin D deficiency should be corrected with vitamin D doses selected to achieve a serum 25-hydroxyvitamin D concentration of at least 20 ng/ml. All patients should receive calcium. Patients with kidney failure should be evaluated and treated for chronic kidney disease-mineral and bone disorder, including renal osteodystrophy. Secondary hyperparathyroidism, in particular, should be treated. Treatment is indicated in the immediate posttransplantation period irrespective of bone mineral density because further rapid bone loss will occur in the first several months after transplantation. Long-term organ transplant recipients should also have bone mass measurement and treatment of osteoporosis. Oral and iv bisphosphonates are the most promising approach for the management of transplantation osteoporosis. Active vitamin D metabolites may have additional benefits in reducing hyperparathyroidism, particularly after kidney transplantation.

Pamidronate in the prevention of bone loss after liver transplantation: a randomized controlled trial

Rapid bone loss and high rates of fractures occur following liver transplantation. To analyze the effect of intravenous pamidronate on bone loss after liver transplantation. A randomized, double-blind, placebo-controlled study was performed. Seventy-nine patients were randomized to two groups of treatment: the pamidronate group (n = 38) was treated with 90 mg/IV of pamidronate within the first 2 weeks and at 3 months after transplantation; the placebo group (n = 41) received glucose infusions at the same time points. All patients received calcium and vitamin D. Bone mineral density (BMD) at the lumbar spine (L(2)-L(4)) and proximal femur using dual energy X-ray absorptiometry and also spinal X-rays were performed before, and at 6 and 12 months after liver transplantation. Biochemical and hormonal determinations were performed previous to transplantation, at 24 h before and after treatment, as well as at 6 and 12 months after liver transplantation. At 12 months after transplantation, there were significant differences in lumbar BMD changes (6 months: pamidronate 1.6% vs. placebo 0.8%, P = NS; 12 months: pamidronate 2.9% vs. placebo 1%, P < 0.05). Femoral neck BMD decreased in the pamidronate- and placebo groups during the first 6 months (6 months: pamidronate -3.1% vs. placebo -2.9%, P = NS; 12 months: pamidronate -3.2% vs. placebo -3.1%, P = NS). BMD at the trochanter remained stable in the pamidronate group, whilst a reduction was observed in the placebo group at 6 months (6 months: pamidronate -0.7% vs. placebo -3.7%, P < 0.05; 12 months: pamidronate -0.5% vs. placebo -1.2%, P = NS). Moreover, no significant differences in the incidence of fractures, serum parathyroid hormone and serum 25-hydroxyvitamin D values between both groups were found. Pamidronate did not increase the risk of serious adverse events. The results of this study show that 90 mg of intravenous pamidronate within the first 2 weeks and at 3 months following liver transplantation preserve lumbar bone mass during the first year, without significant adverse events. However, pamidronate does not reduce bone loss at the femoral neck and furthermore it does not reduce skeletal fractures.

Post-transplantation osteoporosis

Osteoporosis is prevalent in transplant recipients and is related to pre- and post-transplantation factors. Low bone density and fractures may antedate transplantation, related to traditional risk factors for osteoporosis, effects of chronic illness, and end-stage organ failure and its therapy, on the skeleton. Bone loss after transplantation is related to adverse effects of immunosuppressive drugs (glucocorticoids and calcineurin inhibitors) on bone remodeling. Newer immunosuppressive medications may permit lower doses of glucocorticoids and may be associated with decreased bone loss and fractures. Bisphosphonates are currently the most effective agents for the prevention and treatment of post-transplantation osteoporosis.

An update on glucocorticoid-induced osteoporosis

PURPOSE OF REVIEW

Glucocorticoids are widely used, often long term, and a major side effect is osteoporosis and increased risk of fracture. This review considers how common is the problem, the patients who are most at risk, our current understanding of mechanisms, and how to prevent and effectively treat glucocorticoid-induced osteoporosis. The actions currently being undertaken in clinical practice are reviewed.

RECENT FINDINGS

Glucocorticoid-induced osteoporosis is an increasing problem that occurs not only in those on high-dose therapy. Advances in our knowledge of the cellular and cytokine mechanisms of bone turnover and glucocorticoid mechanisms of action are leading to a better understanding of how glucocorticoids affect bone cells and novel ways of prevention. Although there are effective treatments to prevent and control glucocorticoid-induced osteoporosis as well as guidelines for their use, they are still not being applied in routine clinical practice.

SUMMARY

Glucocorticoid-induced osteoporosis is a significant problem. Although our understanding of effective prevention and treatment strategies is improving, there needs to be better implementation of these strategies.

Long-term care of the liver transplant recipient

As survival increases after liver transplantation, common issues that arise involve immunosuppression-related complications and primary health care. Proper emphasis on the prevention and treatment of post-liver transplant complications, such as diabetes mellitus, dyslipidemia, renal dysfunction, osteoporosis, and obesity, requires careful screening and long-term surveillance to minimize the progression of these complications. Active involvement by internists and subspecialists is necessary and a multidisciplinary approach should be undertaken. Liver transplantation should be viewed as a lifelong commitment by both patient and physician.