Increased incidence of fractures in recipients of hematopoietic stem-cell transplantation

Increased risk of hip and major osteoporotic fractures in 8463 patients who have undergone stem cell transplantation, a Swedish population-based study

In this retrospective cohort study of adult stem cell transplanted patients (n = 8463), a significant increased risk of both MOF and hip fractures was seen compared with the Swedish population and occurred in mean more than 2 years after stem cell transplantation.

PURPOSE

To explore the risk for osteoporotic fracture in patients who have undergone hematopoietic stem cell transplantation (HSCT) compared with the Swedish population.

METHODS

The risk of osteoporotic fractures was determined in a retrospective population cohort study of adult (≥ 18 years) Swedish patients (n = 8463), who were transplanted with HSCT 1997-2016 and compared with all adults living in Sweden during the same period.

RESULTS

In the total study group (n = 8463), 90 hip fractures (1.1% both in males and females) and 361 major osteoporotic fractures (MOF) (3.2% in men and 6.0% in women) were identified. In the total study population, the ratio of observed and expected number of hip fracture for women was 1.99 (95% CI 1.39-2.75) and for men 2.54 (95% CI 1.91-3.31). The corresponding ratio for MOF in women was 1.36 (CI 1.18-1.56) and for men 1.61 (CI 1.37-1.88). From 2005 onwards, when differentiation in the registry between allo- and auto-HSCT was possible, the observed number of hip fracture and MOF in allo-HSCT (n = 1865) were significantly increased (observed/expected hip fracture 5.24 (95% CI 3.28-7.93) and observed/expected MOF 2.08 (95% CI 1.63-2.62)). Fractures occurred in mean 2.7 (hip) and 2.5 (MOF) years after allo-HSCT. Graft-versus-host disease (GVHD) was not associated with an increased risk of fracture.

CONCLUSION

Patients who underwent HSCT had an increased risk of both hip and major osteoporotic fracture compared with the Swedish population and occurred in 4.3% of patients. GVHD was not statistically significantly associated with fracture risk.

Bone Density and Trabecular Bone Score Decline Rapidly in the First Year After Bone Marrow Transplantation with a Marked Increase in 10-Year Fracture Risk

As outcomes from allogeneic bone marrow transplantation (BMT) have improved, prevention of long-term complications, such as fragility fractures, has gained importance. We aimed to assess areal bone mineral density (aBMD) and trabecular bone score (TBS) changes post BMT, and determine their relationship with fracture prevalence. Patients who attended the Royal Melbourne Hospital (RMH) BMT clinic between 2005-2021 were included. Patient characteristics and dual-energy X-ray absorptiometry (DXA) values were collected from the electronic medical record and a survey. TBS iNsight™ was used to calculate TBS for DXA scans performed from 2019 onwards. 337 patients with sequential DXAs were eligible for inclusion. Patients were primarily male (60%) and mean age ± SD was 45.7 ± 13.4 years. The annualised decline in aBMD was greater at the femoral neck (0.066g/cm2 (0.0038-0.17)) and total hip (0.094g/cm2 (0.013-0.19)), compared to the lumbar spine (0.049g/cm2 (- 0.0032-0.16)), p < 0.0001. TBS declined independently of aBMD T-scores at all sites. Eighteen patients (5.3%) sustained 19 fractures over 3884 person-years of follow-up post-transplant (median follow-up 11 years (8.2-15)). This 5.3% fracture prevalence over the median 11-year follow-up period is higher than what would be predicted with FRAX® estimates. Twenty-two patients (6.5%) received antiresorptive therapy, and 9 of 18 (50%) who fractured received or were on antiresorptive therapy. In BMT patients, aBMD and TBS decline rapidly and independently in the first year post BMT. However, FRAX® fracture probability estimates incorporating these values significantly underestimate fracture rates, and antiresorptive treatment rates remain relatively low.

Loading dose vitamin D3 improves vitamin D insufficiency in adults undergoing hematopoietic stem cell transplantation: A randomized controlled trial

Allogeneic hematopoietic stem cell transplant (aHSCT) patients are well known to be at high risk of vitamin D (vit D) deficiency. This study assessed whether a loading dose (100,000 IU) of vitamin D3 pre-aHSCT could effectively achieve and maintain sufficient post-transplant vit D levels (serum total 25 hydroxy vitamin D (25(OH)D) ≥ 75nmol/L). Dual-energy X-ray absorptiometry (DXA) was also conducted for bone health evaluation. 74 patients were enrolled and randomly assigned, in a 1:1 ratio, either to the high vit D group (single loading dose (100,000 IU) plus 2,000 IU vit D3 daily) or the control group (2,000 IU vit D3 daily). Vit D levels were measured at three time points (baseline, day 30 and day 100 post-aHSCT). At baseline, fewer than 50% patients had a sufficient 25(OH)D (control: 42.9%; high vit D: 43.6%). The proportion of patients with sufficient 25(OH)D (nmol/L) was increased at day 30 and day 100, with a trend of higher proportion in the high vit D group at day 30 (high vit D vs. control: 89.7% vs. 74.3%, p = 0.08). The increased 25(OH)D was significantly higher in the high vit D group at day 30 (high vit D vs. control: 29±25.2 vs. 14 ±21.9, p = 0.01). Insufficient vit D level before transplant (baseline) was an independent risk factor for vit D insufficiency (serum 25(OH)D < 75nmol/L) post-aHSCT (OR = 4.16, p = 0.03). DXA suggested significant bone loss for total hip in both groups, and in the femoral neck for the control group only. In conclusion, single loading dose vitamin D3 significantly increased total 25(OH)D levels at day 30 post-transplant, and the intervention was especially beneficial for patients with baseline vit D insufficiency. We acknowledge that the primary outcome at day 100 post-aHSCT indicating superiority of loading dose versus daily dose supplementation was not met.

The level of serum albumin is associated with renal prognosis and renal function decline in patients with chronic kidney disease

OBJECTIVE

The study's purpose is to explore the link of serum albumin on renal progression in patients with chronic kidney disease (CKD).

METHODS

This study was a secondary analysis of a prospective cohort study in which a total of 954 participants were non-selectively and consecutively collected from the research of CKD-ROUTE in Japan between November 2010 and December 2011. We evaluated the association between baseline ALB and renal prognosis (initiation of dialysis or 50% decline in eGFR from baseline) and renal function decline (annual eGFR decline) using the Cox proportional-hazards and linear regression models, respectively. We performed a number of sensitivity analyses to ensure the validity of the results. In addition, we performed subgroup analyses.

RESULTS

The included patients had a mean age of (66.86 ± 13.41) years, and 522 (69.23%) were male. The mean baseline ALB and eGFR were (3.89 ± 0.59) g/dL and (33.43 ± 17.97) ml/min/1.73 m². The annual decline in eGFR was 2.65 mL/min/1.73 m²/year. 218 (28.9%) individuals experienced renal prognosis during a median follow-up period of 36.0 months. The baseline ALB was inversely linked with renal prognosis (HR = 0.61, 95%CI: 0.45, 0.81) and renal function decline (β = -1.41, 95%CI: -2.11, -0.72) after controlling for covariates. The renal prognosis and ALB had a non-linear connection, with ALB's inflection point occurring at 4.3 g/dL. Effect sizes (HR) were 0.42 (0.32, 0.56) and 6.11 (0.98, 38.22) on the left and right sides of the inflection point, respectively. There was also a non-linear relationship between ALB and renal function decline, and the inflection point of ALB was 4.1 g/dL. The effect sizes(β) on the left and right sides of the inflection point were -2.79(-3.62, -1.96) and 0.02 (-1.97, 1.84), respectively.

CONCLUSION

This study shows a negative and non-linear association between ALB and renal function decline as well as renal prognosis in Japanese CKD patients. When ALB is lower than 4.1 g/dL, ALB decline was closely related to poor renal prognosis and renal function decline. From a therapeutic point of view, reducing the decline in ALB makes sense for delaying CKD progression.

Fracture risk and assessment in adults with cancer

Individuals with cancer face unique risk factors for osteoporosis and fractures. Clinicians must consider the additive effects of cancer-specific factors, including treatment-induced bone loss, and premorbid fracture risk, utilizing FRAX score and bone mineral densitometry when available. Pharmacologic therapy should be offered as per cancer-specific guidelines, when available, or local general osteoporosis guidelines informed by clinical judgment and patient preferences. Our objective was to review and summarize the epidemiologic burden of osteoporotic fracture risk and fracture risk assessment in adults with cancer, and recommended treatment thresholds for cancer treatment-induced bone loss, with specific focus on breast, prostate, thyroid, gynecological, multiple myeloma, and hematopoietic stem cell transplant. This narrative review was informed by PubMed searches to July 25, 2022, that combined terms for cancer, stem cell transplantation, fracture, bone mineral density (BMD), trabecular bone score, FRAX, Garvan nomogram or fracture risk calculator, QFracture, prediction, and risk factors. The literature informs that cancer can impact bone health in numerous ways, leading to both systemic and localized decreases in BMD. Many cancer treatments can have detrimental effects on bone health. In particular, hormone deprivation therapies for hormone-responsive cancers such as breast cancer and prostate cancer, and hematopoietic stem cell transplant for hematologic malignancies, adversely affect bone turnover, resulting in osteoporosis and fractures. Surgical treatments such as hysterectomy with bilateral salpingo-oophorectomy for gynecological cancers can also lead to deleterious effects on bone health. Radiation therapy is well documented to cause localized bone loss and fractures. Few studies have validated the use of fracture risk prediction tools in the cancer population. Guidelines on cancer-specific treatment thresholds are limited, and major knowledge gaps still exist in fracture risk and fracture risk assessment in patients with cancer. Despite the limitations of current knowledge on fracture risk assessment and treatment thresholds in patients with cancer, clinicians must consider the additive effects of bone damaging factors to which these patients are exposed and their premorbid fracture risk profile. Pharmacologic treatment should be offered as per cancer-specific guidelines when available, or per local general osteoporosis guidelines, in accordance with clinical judgment and patient preferences.

Endocrine sequelae of hematopoietic stem cell transplantation: Effects on mineral homeostasis and bone metabolism

Hematopoietic stem cell transplantation (HSCT) is an established therapeutic strategy for the treatment of malignant (leukemia and lymphoma) and non-malignant (thalassemia, anemia, and immunodeficiency) hematopoietic diseases. Thanks to the improvement in patient care and the development of more tolerable conditioning treatments, which has extended the applicability of therapy to the elderly, a growing number of patients have successfully benefited from HSCT therapy and, more importantly, HSCT transplant-related mortality has consistently reduced in recent years. However, concomitantly to long term patient survival, a growing incidence of late HSCT-related sequelae has been reported, being variably associated with negative effects on quality of life of patients and having a non-negligible impact on healthcare systems. The most predominantly observed HSCT-caused complications are chronic alterations of the endocrine system and metabolism, which endanger post-operative quality of life and increase morbidity and mortality of transplanted patients. Here, we specifically review the current knowledge on HSCT-derived side-effects on the perturbation of mineral metabolism; in particular, the homeostasis of calcium, focusing on current reports regarding osteoporosis and recurrent renal dysfunctions that have been observed in a percentage of HSC-transplanted patients. Possible secondary implications of conditioning treatments for HSCT on the physiology of the parathyroid glands and calcium homeostasis, alone or in association with HSCT-caused renal and bone defects, are critically discussed as well.

Association between hemoglobin and chronic kidney disease progression: a secondary analysis of a prospective cohort study in Japanese patients

OBJECTIVE

Anemia has been reported as a risk factor for chronic kidney disease (CKD) progression. However, there are still few studies examining the relationship between specific hemoglobin (Hb) levels and renal prognosis and renal function decline simultaneously. Meanwhile, the possible non-linear relationship between Hb and CKD progression also deserves further exploration. On that account, our primary goal is to explore the link of Hb on renal prognosis and renal function decline in patients with CKD.

METHODS

This study was a secondary analysis of a prospective cohort study, which consecutively and non-selectively collected 962 participants from the research of CKD-ROUTE in Japan from November 2010 to December 2011. We used the Cox proportional-hazards and linear regression models to evaluate the independent association between baseline Hb and renal prognosis (renal composite endpoint, initiation of dialysis during follow-up or 50% decline in eGFR from baseline) and renal function decline(annual eGFR decline), respectively. A multivariate Cox proportional hazards regression analysis with cubic spline functions model and smooth curve fitting (penalized spline method) were conducted to address Hb and CKD prognosis's non-linearity. At the same time, a generalized additive model (GAM) and smooth curve fitting (penalized spline method) was conducted to explore the exact shape of the curve between Hb and renal function decline. Additionally, we did a series of sensitivity analyses to ensure the robustness of the results. Moreover, we conducted subgroup analyses.

RESULTS

The mean age of the included patients was 67.35 ± 13.56 years old, and 69.65% were male. The mean baseline Hb and estimated glomerular filtration rate (eGFR) was 12.06 ± 2.21 g/dL and 33.04 ± 18.01 ml/min per 1.73 m². The annual decline in eGFR was 2.09 mL/min/1.73 m²/year. During a median follow-up time of 33.5 months, 252(26.2%) people experienced renal composite endpoint. After adjusting covariates, the results showed that Hb was negatively associated with renal composite endpoint (HR = 0.836, 95%CI: 0.770, 0.907) and renal function decline (β = -0.436, 95%CI: -0.778, -0.093). There was also a non-linear relationship between Hb and renal composite endpoint, and the inflection point of Hb was 8.6 g/dL. The effect sizes(HR) on the left and right sides of the inflection point were 1.257 (0.841, 1.878) and 0.789 (0.715, 0.870), respectively. And the sensitive analysis demonstrated the robustness of the results. Subgroup analysis showed that Hb was more strongly associated with the renal composite endpoint in non-hypertensive, SBP < 140 mmHg, urine protein-to-creatinine ratio (UPCR) < 0.5 g/gCr, and diuretic use patients. In contrast, the weaker association was probed in hypertensive and non-diuretic use patients and the patients with SBP ≥ 140 mmHg, and UPCR ≥ 0.5 g/gCr.

CONCLUSION

This study demonstrates a negative and non-linear relationship between Hb and renal prognosis and renal function decline in Japanese CKD patients. Hb is strongly related to renal prognosis when Hb is above 8.6 g/dL.

Multidisciplinary Care of a Vertebral Fracture in a Patient with Hematopoietic Stem Cell Transplant: Safety Appropriateness in Interventional Pain Management and Rehabilitation Considerations

Bone loss leading to fragility fracture is a highly prevalent late effect in hematopoietic stem-cell transplant patients, who are affected 8–9 times more than the general population, particularly for vertebral compression fractures. Spinal interventions such as lumbar epidural steroid injections and vertebral augmentation may be helpful for providing pain relief and improved function, quality of life and return to ambulation. However, interventional procedures should be approached with caution in these patients. Our study found that there is a paucity of scientific studies addressing the risks of spinal injections in these patients and there is no absolute recommendation specific to spinal injections in patients receiving immunosuppressive agents or who have a history of solid organ or hematopoietic stem cell transplant. It is imperative to consider proper timing of the intervention to minimize risks while optimizing the benefits of the intervention combined with a well-defined post-transplant rehabilitation plan. Moreover, the decision to proceed with spinal interventions should be done case by case and with caution. Therefore, this article reports the case of a multidisciplinary treatment for a vertebral compression fracture in a patient with a hematopoietic stem-cell transplant, in particular discussing safety appropriateness in interventional pain management and rehabilitation considerations for this condition in this patient population.

Osteoporosis: Common Side Effect

For osteoporosis, standards of care are based on emerging evidence-based practice.&nbsp;Osteopenia, bone density that is lower than normal, is a less severe form of bone loss than osteoporosis.&nbsp;Osteoporosis is the most common metabolic bone disease, characterized by low mineral bone mass and microdeterioration of bone tissue.

Bone Health Outcomes at 1 Year after Hematopoietic Stem Cell Transplantation in a Heterogeneous Pediatric Population

Impaired bone mineral density (BMD) is a known complication of hematopoietic stem cell transplantation (HSCT) in adults and may lead to increased fracture risk. Less is known in children about the risks for impaired BMD and fragility (low trauma) fractures after HSCT. In this study, we evaluated the incidence of fragility fractures in a large diverse pediatric HSCT recipient population and identified risk factors for both fracture and impaired BMD. We reviewed the records of 237 patients age ≤21 years at the time of transplantation who underwent HSCT at our institution between January 2015 and March 2018. The primary endpoint was the incidence of fragility fractures, and the secondary endpoint was assessment of BMD on dual-energy X-ray absorptiometry (DXA). DXA studies were available for analysis in 79 of 206 patients who were alive at 1 year after HSCT, and the median height-for-age adjusted z-score for spine BMD was 0.15. Among the 237 patients in this study, 25 (10.5%) had evidence of at least 1 fragility fracture on imaging. In the patients with at least 1 fragility fracture, 18 (72%) sustained spine fractures. The median time to fracture was 5.9 months after HSCT. Mortality at 1 year was proportionally higher, although not statistically significantly so (P = .11) in patients who had at least 1 fragility fracture (24%; 6 of 25) compared with patients without a fragility fracture (12%; 25 of 212). Vitamin D status at 1 year post-HSCT was sufficient (>20 ng/mL) in 94% of the patients assessed (160 of 171). There was no difference in the incidence of fracture between vitamin D-sufficient patients and vitamin D-insufficient patients (P = 1.0). The incidence of fracture was significantly higher in patients with graft-versus-host disease (GVHD) compared with those without GVHD (15% vs 6%; P = .02). There was no significant difference in fracture occurrence between patients who received reduced-intensity conditioning and those who received myeloablative conditioning. The cumulative glucocorticoid dose was significantly associated with fracture in patients exposed to glucocorticoids for >3 months (P = .03). The incidence of fragility fractures, especially vertebral compression fractures, after pediatric HSCT is striking. Furthermore, there may have been additional, asymptomatic patients in our cohort with undetected, occult fractures. The high incidence of fragility fractures seen in this study advocates for establishing bone health screening protocols with attention to spinal imaging in pediatric patients undergoing HSCT.

Vitamin D Deficiency, Osteoporosis and Effect on Autoimmune Diseases and Hematopoiesis: A Review

Vitamin D (VD) is essential for bone homeostasis, but it is also involved in pleiotropic effects on various organs and tissues. In adults, VD deficiency can cause or exacerbate osteoporosis and induce osteomalacia. However, every tissue and cell in the body has a VD receptor, including the brain, heart, stomach, pancreas, skin, gonads, and immune cells, and a deficiency may modify the function of these organs. Thus, the wide-ranging actions of VD help to explain why a reduction in VD amount has been correlated with numerous chronic diseases. In fact, VD deficiency increases the risk of osteoporosis and several other diseases and complications characterized by impaired bone metabolisms, such as autoimmune diseases, inflammatory bowel diseases, allergy, endocrinological diseases, hematological malignancies, and bone marrow transplantation. This review aims to investigate the link between VD deficiency, osteoporosis, and its concomitant diseases. Further epidemiological and mechanistic studies are necessary in order to ascertain the real role of hypovitaminosis in causing the reported diseases; however, adequate vitamin supplementation and restoration of metabolic normality could be useful for better management of these pathologies.

The role of bone-modifying agents in myeloma bone disease

Bone disease is common in patients with multiple myeloma (MM), which manifests as bone pain and skeletal-related events (SREs) such as pathological fractures and spinal cord compression. Myeloma bone disease (MBD) can adversely affect the quality of life of patients and have negative effects on morbidity and mortality. The pathogenesis of MBD is complex, and several factors are involved in the dysregulation of bone metabolism and uncoupling of bone remodeling, which result in net bone loss and devastating SREs. Broadly speaking, elevated osteoclast activity, suppressed osteoblast activity, and an aberrant marrow microenvironment play a role in MBD. Interaction of MM cells with the main bone cell osteocytes also promote further bone destruction. This review focuses on the role of bone-modifying agents in the prevention and treatment of MBD. The mainstay of MBD prevention are antiresorptive agents, bisphosphonates and denosumab. However, these agents do not play a direct role in bone formation and repair of existing MBD. Newer agents with anabolic effects such as anti-sclerostin antibodies, parathyroid hormone, anti-Dickkopf-1 antibodies, and others have shown potential in repair of MBD lesions. With the development of several new agents, the treatment landscape of MBD is likely to evolve in the coming years. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

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.

Risk Factors for Hematopoietic Stem Cell Transplantation-Associated Bone Loss

Hematopoietic stem cell transplantation (HSCT), including bone marrow transplantation, is the treatment of choice for many hematologic diseases, including hematologic malignancies and different types of anemia. The use of HSCT is increasing annually, mainly because advanced research that has been conducted in this area has exponentially expanded the indications for HSCT and significantly improved transplantation techniques and supportive care practices. Collectively, these improvements have led to an increase in the overall survival of HSCT patients. However, as post-HSCT survival is increasing, awareness of the potential late complications of HSCT is also growing. Unpredictable bone loss is one of the major post-HSCT complications that can cause significant morbidity and impair the quality of life of survivors. Although the exact mechanism of post-HSCT bone loss is not yet known, previous studies have suggested that numerous factors, including destructive preparative regimens (eg, high-dose chemotherapy, total body irradiation), treatment-related complications (eg, graft-versus-host disease), endocrine abnormalities (eg, diabetes mellitus, thyroid dysfunction, adrenal insufficiency), lack of physical activity, and the underlying disease itself are responsible for HSCT-associated bone loss. Sufficient data have been collected to suggest that post-HSCT bone loss can be prevented and treated using the same preventive and treatment modalities as used for the general population. Various guidelines have been formulated to help keep a check on HSCT recipients' deteriorating bone health.

Skeletal Stem Cells as the Developmental Origin of Cellular Niches for Hematopoietic Stem and Progenitor Cells

The skeletal system is a highly complex network of mesenchymal, hematopoietic, and vasculogenic stem cell lineages that coordinate the development and maintenance of defined microenvironments, so-called niches. Technological advancements in recent years have allowed for the dissection of crucial cell types as well as their autocrine and paracrine signals that regulate these niches during development, homeostasis, regeneration, and disease. Ingress of blood vessels and bone marrow hematopoiesis are initiated by skeletal stem cells (SSCs) and their more committed downstream lineage cell types that direct shape and form of skeletal elements. In this chapter, we focus on the role of SSCs as the developmental origin of niches for hematopoietic stem and progenitor cells. We discuss latest updates in the definition of SSCs, cellular processes establishing and maintaining niches, as well as alterations of stem cell microenvironments promoting malignancies. We conclude with an outlook on future studies that could take advantage of SSC-niche engineering as a basis for the development of new therapeutic tools to not only treat bone-related diseases but also maladies stemming from derailed niche dynamics altering hematopoietic output.

Spatio-Temporal Bone Remodeling after Hematopoietic Stem Cell Transplantation

The interaction of hematopoietic cells and the bone microenvironment to maintain bone homeostasis is increasingly appreciated. We hypothesized that the transfer of allogeneic T lymphocytes has extensive effects on bone biology and investigated trabecular and cortical bone structures, the osteoblast reconstitution, and the bone vasculature in experimental hematopoietic stem cell transplantations (HSCT). Allogeneic or syngeneic hematopoietic stem cells (HSC) and allogeneic T lymphocytes were isolated and transferred in a murine model. After 20, 40, and 60 days, bone structures were visualized using microCT and histology. Immune cells were monitored using flow cytometry and bone vessels, bone cells and immune cells were fluorescently stained and visualized. Remodeling of the bone substance, the bone vasculature and bone cell subsets were found to occur as early as day +20 after allogeneic HSCT (including allogeneic T lymphocytes) but not after syngeneic HSCT. We discovered that allogeneic HSCT (including allogeneic T lymphocytes) results in a transient increase of trabecular bone number and bone vessel density. This was paralleled by a cortical thinning as well as disruptive osteoblast lining and loss of B lymphocytes. In summary, our data demonstrate that the adoptive transfer of allogeneic HSCs and allogeneic T lymphocytes can induce profound structural and spatial changes of bone tissue homeostasis as well as bone marrow cell composition, underlining the importance of the adaptive immune system for maintaining a balanced bone biology.

Bone Health Management After Hematopoietic Cell Transplantation: An Expert Panel Opinion from the American Society for Transplantation and Cellular Therapy

Bone health disturbances commonly occur after hematopoietic cell transplantation (HCT) with loss of bone mineral density (BMD) and avascular necrosis (AVN) foremost among them. BMD loss is related to pretransplantation chemotherapy and radiation exposure and immunosuppressive therapy for graft-versus-host-disease (GVHD) and results from deficiencies in growth or gonadal hormones, disturbances in calcium and vitamin D homeostasis, as well as osteoblast and osteoclast dysfunction. Although the pathophysiology of AVN remains unclear, high-dose glucocorticoid exposure is the most frequent association. Various societal treatment guidelines for osteoporosis exist, but the focus is mainly on menopausal-associated osteoporosis. HCT survivors comprise a distinct population with unique comorbidities, making general approaches to bone health management inappropriate in some cases. To address a core set of 16 frequently asked questions (FAQs) relevant to bone health in HCT, the American Society of Transplant and Cellular Therapy Committee on Practice Guidelines convened a panel of experts in HCT, adult and pediatric endocrinology, orthopedics, and oral medicine. Owing to a lack of relevant prospective controlled clinical trials that specifically address bone health in HCT, the answers to the FAQs rely on evidence derived from retrospective HCT studies, results extrapolated from prospective studies in non-HCT settings, relevant societal guidelines, and expert panel opinion. Given the heterogenous comorbidities and needs of individual HCT recipients, answers to FAQs in this article should be considered general recommendations, with good medical practice and judgment ultimately dictating care of individual patients. Readers are referred to the Supplementary Material for answers to additional FAQs that did not make the core set.

Effects of Hormone Replacement Therapy on Bone Mass After Allogeneic Hematopoietic Stem Cell Transplantation

CONTEXT AND OBJECTIVES

This study aimed to assess the effects of hormone replacement therapy (HRT) on bone mineral density (BMD) in young women who underwent allogeneic hematopoietic stem cell transplantation (HSCT).

PARTICIPANTS AND METHODS

This retrospective cohort included 234 female patients with premature ovarian insufficiency (POI) who underwent allogeneic HSCT between April 2009 and April 2016 at Seoul St. Mary's Hospital in Seoul, Korea. Inclusion criteria included adult patients who were age 40 years or younger at the time of transplantation and were followed for at least 3 years after HSCT.

RESULTS

At the first and second years after HRT, there was a significant increase in the BMD of the lumbar spine of the HRT group (n = 170) compared to that of the non-HRT group (n = 64) (P = .033 and P = .047, respectively). The BMD of the lumbar spine significantly increased from baseline by 4.16 ± 4.39% and 5.42 ± 5.86% after 1 and 2 years of HRT, respectively (P = .037 and P = .021). The BMD of the femoral neck and total hip also showed a significant percentage increase from baseline after 2 years of HRT. These changes were significant even in the presence of graft-versus-host disease or steroid exposure. For HRT that was initiated within 12 months after HSCT, the increase in BMD in the lumbar spine was greatest after 2 years of HRT.

CONCLUSIONS

These results support that early and active hormonal therapy might be beneficial for BMD in female HSCT recipients with POI.

Long-term Follow-up of Hematopoietic Stem Cell Transplant Survivors: A Focus on Screening, Monitoring, and Therapeutics

Annually, ~50,000 patients undergo hematopoietic stem cell transplantation (HCT) worldwide with almost 22,000 of these patients receiving HCT in the United States. HCT is a curative option for a wide range of hematologic malignancies, and advances in transplantation medicine have resulted in an increase in HCT survivors. It is anticipated that the number of HCT survivors will more than double from 242,000 in 2020 to ~500,000 in 2030. Survivors of HCT are at an increased risk of developing late complications due to exposure to chemotherapy and/or radiation in the pre-, peri-, and post-HCT phases and these cumulative exposures have the potential to damage normal tissue. This tissue damage leads to the early onset of chronic health conditions resulting in premature mortality in HCT survivors, who have a 15-year cumulative incidence of severe or life-threatening chronic health conditions exceeding 40%. Due to the significant burden of morbidity in HCT survivors and the delay in the development of long-term complications, this delicate patient population requires life-long monitoring due to the risk for neuropsychological, cardiac, pulmonary, renal, hepatic, ocular, skeletal, cardiac, endocrine, fertility, and sexual health complications, as well as secondary neoplasms. This review will focus on recent advances in screening, monitoring, and therapeutics for late-occurring or long-term complications in HCT survivors.

Investigation and Management of Bone Mineral Density Following Hematopoietic Cell Transplantation: A Survey of Current Practice by the Transplant Complications Working Party of the European Society for Blood and Marrow Transplantation

Reduced bone mineral density (BMD) is a well-recognized complication of hematopoietic cell transplantation (HCT), with significant drops in BMD occurring within the first 12 months after HCT. Guidance on identifying and managing this complication is available in several published guidelines. In this study, we investigated current practices in the investigation and management of low BMD in centers registered with the European Society for Blood and Marrow Transplantation (EBMT). A questionnaire about bone health was sent to all registered centers, and responses were received from 99 centers in 25 countries (52%) currently registered with the EBMT. Our data highlight considerable heterogeneity in practices across European centers in relation to investigations, management, and use of guidelines. Our data demonstrate the need for better dissemination and implementation of existing guidelines and also for the development of multidisciplinary guidelines with input from all relevant stakeholders.

Risk Factors and Management of Osteoporosis Post-Transplant

Bone and mineral disorders are common after organ transplantation. Osteoporosis post transplantation is associated with increased morbidity and mortality. Pathogenesis of bone disorders in this particular sub set of the population is complicated by multiple co-existing factors like preexisting bone disease, Vitamin D deficiency and parathyroid dysfunction. Risk factors include post-transplant immobilization, steroid usage, diabetes mellitus, low body mass index, older age, female sex, smoking, alcohol consumption and a sedentary lifestyle. Immunosuppressive medications post-transplant have a negative impact on outcomes, and further aggravate osteoporotic risk. Management is complex and challenging due to the sub-optimal sensitivity and specificity of non-invasive diagnostic tests, and the underutilization of bone biopsy. In this review, we summarize the prevalence, pathophysiology, diagnostic tests and management of osteoporosis in solid organ and hematopoietic stem cell transplant recipients.

Bone turnover markers as an aid to monitor osteoporosis following allogeneic hematopoietic stem cell transplantation

Bone turnover markers (BTMs) are useful parameters for assessing fracture risk and unlike bone mineral density (BMD), can be measured at any institution. However, BTM values have not been established in patients post-allogeneic hematopoietic stem cell transplantation (allo-HSCT). We investigated the practicality of BTMs in patients who underwent allo-HSCT by measuring levels of the serum bone resorption marker, tartrate-resistant acid phosphatase-5b (TRACP-5b), and the bone formation marker, bone-specific alkaline phosphatase (BAP), together with BMD, 1 month before and 6 months after allo-HSCT. Patients were classified into either the alendronate group (n = 14) if alendronate treatment (35 mg orally per week) was administered before allo-HSCT or within 1 month after allo-HSCT, or the control group (n = 16), in which patients did not receive alendronate treatment. Despite the high frequency of corticosteroids users in the alendronate group (71.4 vs. 18.9%; p < 0.01), the mean percentage changes in BMD at the lumbar spine (- 2.9 vs. - 3.1%; p = 0.44) and femoral neck (- 3.2 vs. - 4.1%; p = 1.00), TRACP-5b levels (- 4.8 vs. 9.9%; p = 0.45), and BAP levels (6.9 vs. 1.0%; p = 0.85) during 6 months did not differ significantly between the alendronate and control groups. Additionally, the percentage changes in BMD at the lumbar spine were negatively associated with the TRACP-5b levels 6 months after allo-HSCT (p = 0.03, r = 0.40). Our results indicate the possible effectiveness of alendronate treatment in allo-HSCT patients. BTM levels could be useful to monitor the BMD changes.

Deterioration of hematopoietic autophagy is linked to osteoporosis

Hematopoietic disorders are known to increase the risk of complications such as osteoporosis. However, a direct link between hematopoietic cellular disorders and osteoporosis has been elusive. Here, we demonstrate that the deterioration of hematopoietic autophagy is coupled with osteoporosis in humans. With a conditional mouse model in which autophagy in the hematopoietic system is disrupted by deletion of the Atg7 gene, we show that incapacitating hematopoietic autophagy causes bone loss and perturbs osteocyte homeostasis. Induction of osteoporosis, either by ovariectomy, which blocks estrogen secretion, or by injection of ferric ammonium citrate to induce iron overload, causes dysfunction in the hematopoietic stem and progenitor cells (HSPCs) similar to that found in autophagy‐defective mice. Transcriptomic analysis of HSPCs suggests promotion of iron activity and inhibition of osteocyte differentiation and calcium metabolism by hematopoietic autophagy defect, while proteomic profiling of bone tissue proteins indicates disturbance of the extracellular matrix pathway that includes collagen family members. Finally, screening for expression of selected genes and an immunohistological assay identifies severe impairments in H vessels in the bone tissue, which results in disconnection of osteocytes from hematopoietic cells in the autophagy‐defective mice. We therefore propose that hematopoietic autophagy is required for the integrity of H vessels that bridge blood and bone cells and that its deterioration leads to osteoporosis.

Relapse- and Immunosuppression-Free Survival after Hematopoietic Stem Cell Transplantation: How Can We Assess Treatment Success for Complex Time-to-Event Endpoints?

In most clinical oncology trials, time-to-first-event analyses are used for efficacy assessment, which often do not capture the entire disease process. Instead, the focus may be on more complex time-to-event endpoints, such as the course of disease after the first event or endpoints occurring after randomization. We propose "relapse- and immunosuppression-free survival" (RIFS) as an innovative and clinically relevant outcome measure for assessing treatment success after hematopoietic stem cell transplant (SCT). To capture the time-dynamic relationship of multiple episodes of immunosuppressive therapy during follow-up, relapse, and nonrelapse mortality, a multistate model was developed. The statistical complexity is that the probability of RIFS is nonmonotonic over time; thus, standard time-to-first-event methodology is inappropriate for formal treatment comparisons. Instead, a generalization of the Kaplan-Meier method was used for probability estimation, and simulation-based resampling was suggested as a strategy for statistical inference. We reanalyzed data from a recently published phase III trial in 201 leukemia patients after SCT. The study evaluated long-term treatment success of standard graft-versus-host disease prophylaxis plus a pretransplant antihuman T-lymphocyte immunoglobulin compared with standard prophylaxis alone. Results suggested that treatment increased the long-term probability of RIFS by approximately 30% during the entire follow-up period, which complements the original findings. This article highlights the importance of complex endpoints in oncology, which provide deeper insight into the treatment and disease process over time. Multistate models combined with resampling are highlighted as a promising tool to evaluate treatment success beyond standard endpoints. An example code is provided in the Supplementary Materials.

Long-Term Endocrine and Metabolic Consequences of Cancer Treatment: A Systematic Review

The number of patients surviving ≥5 years after initial cancer diagnosis has significantly increased during the last decades due to considerable improvements in the treatment of many cancer entities. A negative consequence of this is that the emergence of long-term sequelae and endocrine disorders account for a high proportion of these. These late effects can occur decades after cancer treatment and affect up to 50% of childhood cancer survivors. Multiple predisposing factors for endocrine late effects have been identified, including radiation, sex, and age at the time of diagnosis. A systematic literature search has been conducted using the PubMed database to offer a detailed overview of the spectrum of late endocrine disorders following oncological treatment. Most data are based on late effects of treatment in former childhood cancer patients for whom specific guidelines and recommendations already exist, whereas current knowledge concerning late effects in adult-onset cancer survivors is much less clear. Endocrine sequelae of cancer therapy include functional alterations in hypothalamic-pituitary, thyroid, parathyroid, adrenal, and gonadal regulation as well as bone and metabolic complications. Surgery, radiotherapy, chemotherapy, and immunotherapy all contribute to these sequelae. Following irradiation, endocrine organs such as the thyroid are also at risk for subsequent malignancies. Although diagnosis and management of functional and neoplastic long-term consequences of cancer therapy are comparable to other causes of endocrine disorders, cancer survivors need individually structured follow-up care in specialized surveillance centers to improve care for this rapidly growing group of patients.

Predictors of impaired bone health in long-term survivors after allogeneic stem cell transplantation

Survival after allogeneic stem cell transplantation (allo-HSCT) has improved, but so have long-term sequelae. We studied risk factors for fractures and impaired bone health in allo-HSCT patients in the Basel HSCT registry from 01/2003 to 12/2014 using cox proportional models adjusted for age, gender and Karnofsky Index. Our primary endpoint was the incidence of fractures. Out of 652 patients, 32 (5.0%) had a new fracture after transplantation (yearly incidence rate of 1.6%, 95% Confidence Interval [95%CI] 1.1-2.3%) and 325 (49.8%) had low bone mineral density (yearly incidence rate of 13.1%, 95%CI 11.6-14.8%), including 36.0% with osteopenia and 13.8% with osteoporosis. We found vitamin D deficiency during follow-up (Hazard Ratio [HR] 1.25, 95%CI 1.11-1.41, p < 0.001), hyperthyroidism before transplantation (HR 4.85, 95%CI 1.05-22.54, p = 0.044), cumulative years of immunosuppressant exposure (HR 1.23, 95%CI 1.07-1.41, p = 0.004 for steroidal and HR 1.09, 95%CI 1.01-1.18, p = 0.025 for non-steroidal drugs) and graft-versus-host disease (acute HR 1.24, 95%CI 1.11-1.40, p < 0.001; chronic HR 2.82, 95%CI 1.12-7.13, p = 0.028) to be significantly associated with fractures. Patients undergoing HSCT are at increased risk of fractures, which is associated with various disease and treatment-specific factors. Early identification of patients at risk may help to improve preventive measures.

Mandibular radiomorphometric assessment of bone mineral density in survivors of pediatric hematopoietic stem-cell transplantation

OBJECTIVE

Hematopoietic stem-cell transplantation (HSCT) childhood survivors of hematologic malignancies are prone to develop late osteopenia and osteoporosis. The purpose of this retrospective study was to quantitatively and qualitatively assess bone mineral density (BMD) in HSCT childhood survivors and to compare the effectiveness of both qualitative and quantitative assessment methods.

METHODS

DESIGN BMD assessment using panoramic radiographs of childhood HSCT survivors aged 3.69-18.88 years using two radiomorphometric indexes. Case-control double-blinded comparison of panoramic radiographic images from childhood HSCT survivors and age- and sex-matched healthy controls. Quantitative assessment was performed by measuring the cortical bone width bilaterally at the mental foramen level. Qualitative assessment was performed using the mandibular cortical index bilaterally on all panoramic images.

RESULTS

Radiographs were taken 6.59-83.95 months after bone marrow transplantation [median±SD=25.92±24.9 months]. Fifty-two panoramic radiographic images were analyzed: 21 from HSCT survivors and 31 from healthy controls aged 3.69-25.1 years [mean±SD=11.89±5.28 years]. The mandibular cortical bone width was 17% smaller in childhood HSCT survivors than in healthy controls (case group: 2.420, control group: 3.307; p=0.00617). Qualitative analysis revealed an increased frequency of severe mandibular cortical erosion in childhood HSCT survivors, although no significant difference was observed (case group: 1.540, control group: 1.490; p=0.32). The interobserver agreement was 85% (Kappa index).

CONCLUSIONS

HSCT childhood survivors exhibit quantitative and qualitative mandibular bone impairments. Further studies are needed to establish an association between mandibular cortical bone impairment and osteoporosis.

Bone management in hematologic stem cell transplant recipients

Autologous and allogeneic hematopoietic stem cell transplantation (HSCT) is the treatment of choice for patients with some malignant and non-malignant hematological diseases. Advances in transplantation techniques and supportive care measures have substantially increased the number of long-term HSCT survivors. This has led to an increasing patient population suffering from the late effects of HSCT, of which, bone loss and its consequent fragility fractures lead to substantial morbidity. Altered bone health, with consequent fragility fractures, and chronic graft-versus-host disease (GVHD) are factors affecting long-term quality of life after HSCT. Hypogonadism, HSCT preparative regimens, nutritional factors, and glucocorticoids all contribute to accelerated bone loss and increased fracture risk. Management strategies should include bone mineral density examination, evaluation of clinical risk factors, and general dietary and physical activity measures. Evidence has accumulated permitting recommendations for more attentiveness to evaluation and monitoring of bone health, with appropriate application of osteoporosis pharmacotherapies to patients at increased risk of bone loss and fracture.

Fracture risk prediction using FRAX in patients following hematopoietic stem cell transplantation

We aimed to study the utility of the FRAX tool in predicting fractures in patient's receiving a hematopoietic stem cell transplantation (HSCT). Our results indicate that the FRAX tool has modest fracture predictive ability in patients greater than 50 years of age at the time of HSCT.

PURPOSE

Identifying patients at high risk of osteoporotic fractures following HSCT is challenging. We aimed to evaluate the utility of the FRAX tool at the time of HSCT in predicting fractures following transplant.

METHODS

We conducted a retrospective chart review of adults (> 18 years) who underwent HSCT at MD Anderson Cancer Center from January 1, 2001, to December 31, 2010, and were followed until December 31, 2013, to identify osteoporotic fractures. Multivariate Cox regression models were built using FRAX score thresholds of low risk < 10%, medium risk 10 to 20%, and high risk > 20% probability of osteoporotic fracture.

RESULTS

We identified 5170 patients who had undergone HSCT, 10% of whom developed an osteoporotic fracture during a median follow-up of 3.2 years. In patients > 65 years of age, those with medium risk (hazard ratio (HR) 2.38, 95% confidence interval (CI) 1.27-4.47) and high risk (HR 3.41, 95% CI 1.73-6.75) had a greater probability of developing an osteoporotic fracture compared to those at low risk. Similar trends were seen in patients 50 to 65 years of age.

CONCLUSIONS

In patients greater than 50 years, the FRAX tool has modest predictive ability and could be used to aid in preventive treatment decision-making at the time of transplant.

Risk of osteoporosis and pathologic fractures in cancer patients who underwent hematopoietic stem cell transplantation: a nationwide retrospective cohort study

Background

Long-term data on post-hematopoietic stem cell transplantation (HSCT) osteoporosis and fracture are limited. This study evaluated the long-term risk of osteoporosis and fracture in cancer patients who underwent HSCT.

Results

The incidence density rate of osteoporosis was 12.5 per 1000 person-years in the HSCT group, which was significantly higher than that in the non-HSCT group (5.65 per 1000 person-years) after adjustment for associated factors and consideration of competing risk factors (adjusted subhazard ratio, 1.48; 95% confidence interval, 1.06–2.07). The incidence density rate of fracture was 4.89 per 1000 person-years in the HSCT group, and the risk of fracture was 1.40 times higher in the HSCT group than in the non-HSCT group (95% confidence interval, 0.83–2.40). The vertebra was the most common site of fracture after HSCT (68.4%). The risk of osteoporosis and fracture significantly increased in post-HSCT patients with both hematological malignancies and solid tumors. Both autologous and allogeneic HSCTs increased the risk of osteoporosis, whereas only autologous HSCT recipients had an increased risk of fracture.

Materials and Methods

This nationwide retrospective cohort study analyzed data from Taiwan's National Health Insurance Research Database. We identified an HSCT group comprising 1040 cancer patients who underwent HSCT during 2000–2008 and a non-HSCT group comprising 4160 propensity score-matched cancer patients who did not undergo HSCT. All patients were followed up until the occurrence of osteoporosis; fracture; December 31, 2011; or withdrawal from the insurance program.

Conclusions

HSCT recipients have an increased risk of osteoporosis.

Insights into cell-free therapeutic approach: Role of stem cell "soup-ernatant"

Current advances in medicine have revolutionized the field of regenerative medicine dramatically with newly evolved therapies for repair or replacement of degenerating or injured tissues. Stem cells (SCs) can be harvested from different sources for clinical therapeutics, which include fetal tissues, umbilical cord blood, embryos, and adult tissues. SCs can be isolated and differentiated into desired lineages for tissue regeneration and cell replacement therapy. However, several loopholes need to be addressed properly before this can be extended for large-scale therapeutic application. These include a careful approach for patient safety during SC treatments and tolerance of recipients. SC treatments are associated with a number of risk factors and require successful integration and survival of transplanted cells in the desired microenvironment with concurrent tissue regeneration. Recent studies have focused on developing alternatives that can replace the cell-based therapy using paracrine factors. The development of stem "cell free" therapies can be devoted mainly to the use of soluble factors (secretome), extracellular vesicles, and mitochondrial transfer. The present review emphasizes on the paradigms related to the use of SC-based therapeutics and the potential applications of a cell-free approach as an alternative to cell-based therapy in the area of regenerative medicine.

Osteoporosis in Frail Patients: A Consensus Paper of the Belgian Bone Club

In this consensus paper, the Belgian Bone Club aims to provide a state of the art on the epidemiology, diagnosis, and management of osteoporosis in frail individuals, including patients with anorexia nervosa, patients on dialysis, cancer patients, persons with sarcopenia, and the oldest old. All these conditions may indeed induce bone loss that is superimposed on physiological bone loss and often remains under-recognized and under-treated. This is of particular concern because of the major burden of osteoporotic fractures in terms of morbidity, mortality, and economic cost. Therefore, there is an urgent need to appreciate bone loss associated with these conditions, as this may improve diagnosis and management of bone loss and fracture risk in clinical practice.

Prevention and treatment of bone loss and fractures in patients undergoing a hematopoietic stem cell transplant: a systematic review and meta-analysis

The most effective method to prevent and treat bone loss following hematopoietic stem cell transplantation (HSCT) remains uncertain. We conducted a comprehensive search in four electronic databases until August 2015. We retrieved articles describing patients with bone loss or fractures who received HSCT. Controlled trials, with a follow-up period of at least 12 months, were included. Twelve studies (19 publications) met our inclusion criteria. A total of 643 participants underwent HSCT (85.7% allogeneic HSCT). There was a statistically significant lower mean bone mineral density (g/cm²) percentage change of the lumbar spine (mean difference (MD) 7.8, 95% confidence interval (CI) 5.6-10.0) and femoral neck (MD 6.7, 95% CI 5.6-7.9) in the bisphosphonate therapy group compared with the control group with no bisphosphonate therapy at 12 months. In a subgroup analysis, seven different comparison groups were evaluated. The rate of fractures or X-ray findings of subclinical vertebral fractures was similar between groups. Bisphosphonates are promising in the prevention and treatment of bone loss following HSCT. Additional research is required to determine whether they reduce long-term fracture risk.

Ibandronate for the prevention of bone loss after allogeneic stem cell transplantation for hematologic malignancies: a randomized-controlled trial

The purpose of this study was to evaluate the effects of ibandronate on bone loss following allogeneic stem cell transplantation (allo-SCT). A single-centered, open-label prospective randomized-controlled study following allo-SCT. The treatment group received 3 mg of intravenous ibandronate quarterly starting within 45 days of allo-SCT. All patients received daily calcium and vitamin D supplements. We compared the changes in bone mineral density (BMD) in the lumbar spine, femoral neck and total hip at 6 and 12 months following allo-SCT between the control and treatment groups. We also assessed relationships between bone loss and cumulative glucocorticoid dose, cumulative tacrolimus dose and acute and chronic graft-versus-host disease (GVHD) by linear regression. In all, 78 patients were enrolled. The treatment group had significantly less BMD loss in the lumbar spine at 6 months (mean percent change 0.06±4.03 (treatment group) versus -2.61±4.2 (control group)) and 12 months (mean percent change 1.27±5.29 (treatment group) versus -1.81±4.49 (control group)) than the control group (P=0.03). Both groups lost more BMD in the femoral neck and total hip than in the lumbar spine at 6 and 12 months. The changes in BMD in the femoral neck and total hip did not differ significantly between groups. Both glucocorticoids and tacrolimus reduced BMD in the lumbar spine, but ibandronate prevented this loss. Ibandronate may reduce bone loss in the lumbar spine in patients who undergo allo-SCT, particularly those who have received high doses of glucocorticoids and/or tacrolimus.

Characterization and Risk Factor Analysis of Osteoporosis in a Large Cohort of Patients with Chronic Graft-versus-Host Disease

The National Institutes of Health Chronic Graft-versus-Host Disease (cGVHD) Consensus Project Ancillary and Supportive Care Guidelines recommend annual assessment of bone mineral density (BMD) to monitor bone health. The study of osteoporosis in patients with cGVHD has been limited to small numbers of patients, and the guidelines are based on experience with other chronic diseases and expert opinion. We hypothesized that the prevalence of osteoporosis is high in a cohort of 258 patients with moderate to severe cGVHD because of prolonged exposure to risk factors for osteoporosis after allogeneic hematopoietic stem cell transplantation. We defined osteoporosis using BMD criteria (T-score ≤-2.5) at 3 anatomic sites-the femoral neck (FN), lumbar spine (LS), and total hip (TH)-and characterized risk factors through univariate and multivariate analyses. We found that low body weight (FN, P < .0001; LS, P = .0002; TH, P < .0001), malnutrition (FN, P = .0002; LS, P = .03; TH, P = .0076), higher platelet count (FN, P = .0065; TH, P = .0025), higher average National Institutes of Health organ score (FN, P = .038), higher prednisone dose (LS, P = .032), lower complement component 3 (LS, P = .0073), and physical inactivity (FN, P = .01) were associated with osteoporosis in at least 1 site. T-scores were significantly lower in the FN compared with the LS or TH (P < .0001 for both). The prevalence of osteoporosis and osteopenia was high (17% and 60%, respectively), supporting current recommendations for frequent monitoring of BMD. The association of higher platelet count in patients with cGVHD and osteoporosis has not been reported previously and represents a new area of interest in the study of osteoporosis after allogeneic hematopoietic stem cell transplantation.

Factors influencing the late phase of recovery after bone mineral density loss in allogeneic stem cell transplantation survivors

Accelerated bone mineral density loss (BMDL) occurs early after allogeneic stem cell transplantation (SCT) and is related to factors such as steroids and chronic GvHD. In order to understand the natural history of BMDL of SCT in the longer term, we evaluated a longitudinal cohort of 148 survivors with a median follow-up of 12 years (range 3-22 years). All women received hormone replacement therapy, and routine calcium/vitamin D supplementation was recommended but ∼50% of patients still had suboptimal vitamin D levels and bisphosphonates were rarely utilized. BMD significantly improved from 5 to 20+ years but the femoral neck and forearm remained vulnerable sites. Younger age, higher pretransplant body mass index (BMI) and increment in BMI post transplant were significantly associated with increased BMD and protected against osteopenia/osteoporosis. These findings support consideration of BMD loss in SCT survivors in two phases, an early phase of BMD loss (3-5 years) followed by a later phase of BMD recovery, with different protective and aggravating factors. Treatment- and transplant-related factors (such as steroids, immunosuppressives, chronic GvHD, vitamin D) are known to impact the early phase of BMD loss but age and BMI are more influential in the late phase of BMD recovery.