In elderly men and women treated for osteoporosis a low creatinine clearance of <65 ml/min is a risk factor for falls and fractures

Degree of Albuminuria is Associated With Increased Risk of Fragility Fractures Independent of Estimated GFR

Introduction

Fragility fractures are common in persons with chronic kidney disease (CKD); however, the association between fragility fractures and albuminuria is not well-studied. The primary objective of this study is to determine the association of albuminuria with incident risk of fragility fractures. The secondary objective is to examine the risk of fragility fracture by estimated glomerular filtration rate (eGFR) and Kidney Disease Improving Global Outcomes (KDIGO) risk categories.

Methods

Community dwelling adults residing in Alberta, Canada who had at least 1 creatinine and albuminuria measurement between April 1, 2008 and March 31, 2019 participated in the study (N = 2.72 million). Incident fragility fractures were identified using Canadian Chronic Disease Surveillance Systems Osteoporosis Working Group algorithms. Albuminuria was categorized as none/mild (albumin-to-creatinine ratio [ACR] <30 mg/g, protein-to-creatinine ratio [PCR] <150 mg/g, trace/negative dipstick); moderate (ACR 30-300 mg/g, PCR 150-500 mg/g, 1+ dipstick) or severe (ACR >300 mg/g, PCR >500 mg/g, ≥2+ dipstick). Multivariable analysis controlled for 42 variables.

Results

Patients with severe albuminuria had an increased risk of hip fracture (odds ratio [OR] = 1.37; 95% confidence interval [CI] 1.28, 1.47]), vertebral fracture (OR = 1.31; 95% CI 1.21, 1.41) and any-type fracture (OR = 1.22; 95% CI 1.17, 1.28) compared with patients with none/mild albuminuria. Patients in the most severe KDIGO risk category had an increased risk of hip fracture (OR = 1.22; 95% CI 1.16, 1.29), vertebral fracture (OR = 1.18; 95% CI 1.09, 1.26) and any type of fracture (OR = 1.25; 95% CI 1.21, 1.30).

Conclusion

This study demonstrates the important role of albuminuria as a risk factor for fragility fractures in CKD and may help inform risk stratification and prevention strategies in this high-risk population category.

Angiotensin II receptor blockers and bone fracture in chronic kidney disease patients: the Fukuoka kidney disease Registry Study

BACKGROUND

Angiotensin II receptor blockers (ARBs) reportedly reduce the risk of developing bone fractures; however, this association remains unclear among patients with chronic kidney disease (CKD).

METHODS

This was a cross-sectional study of 3380 CKD patients enrolled in the Fukuoka Kidney disease Registry Study, a multicenter prospective observational cohort study of non-dialysis-dependent CKD patients. The patients were divided into two groups, those taking ARBs and those who were not. Logistic regression models were used to examine the association between ARBs and bone fracture.

RESULTS

Approximately 67.0% of the participants were on ARBs, and 6.3% had a history of bone fracture. The history of bone fracture was significantly lower in patients with prescribed ARB and remained significant even after multivariable adjustment (odds ratio, 0.68; 95% confidence interval, 0.51-0.93). Other antihypertensive drugs, such as thiazide diuretics, which were reportedly helpful in preventing fractures, did not alter the bone fracture history and did not change among ARB users and non-users.

CONCLUSIONS

The present study showed that administering ARB was significantly associated with a lower frequency of bone fracture history.

Predictive factors for achievement of treatment goals in patients with postmenopausal osteoporosis treated with denosumab

OBJECTIVES

To investigate efficacy of long-term treatment with denosumab and predictive factors for achievement of treatment goals in patients with postmenopausal osteoporosis (PMO).

METHODS

We enrolled 111 PMO patients who had T-scores ≤-2.5 either at the lumbar spine (L-) or femoral neck (FN-), who had never been treated for osteoporosis, and who could be followed for at least 3 years. We first evaluated changes in bone mineral density (BMD) for up to 7 years. We next defined the treatment goal as the achievement of a T-score >-2.5 at month 36 and performed multivariate analysis to identify predictive factors for achievement of the goal.

RESULTS

Lumbar spine- and femoral neck bone-mineral density increased yearly for 7 years. Among 87 patients with baseline L-T-scores ≤-2.5, better baseline L-T-scores predicted achievement of L-T-scores >-2.5 at month 36. The cut-off value for baseline L-T-score was -3.4. Among 76 patients with baseline FN-T-scores ≤-2.5, better baseline FN-T-scores predicted achievement of FN-T-scores >-2.5 at month 36. The cut-off value for baseline FN-T-scores was -2.8.

CONCLUSIONS

Long-term treatment with denosumab was effective in PMO patients. As better baseline T-score predicted achievement of T-scores >-2.5, early initiation of treatment will contribute to better outcome.

Bone Disease in Chronic Kidney Disease and Kidney Transplant

Chronic Kidney Disease-Mineral and Bone Disorder (CKD-MBD) comprises alterations in calcium, phosphorus, parathyroid hormone (PTH), Vitamin D, and fibroblast growth factor-23 (FGF-23) metabolism, abnormalities in bone turnover, mineralization, volume, linear growth or strength, and vascular calcification leading to an increase in bone fractures and vascular disease, which ultimately result in high morbidity and mortality. The bone component of CKD-MBD, referred to as renal osteodystrophy, starts early during the course of CKD as a result of the effects of progressive reduction in kidney function which modify the tight interaction between mineral, hormonal, and other biochemical mediators of cell function that ultimately lead to bone disease. In addition, other factors, such as osteoporosis not apparently dependent on the typical pathophysiologic abnormalities resulting from altered kidney function, may accompany the different varieties of renal osteodystrophy leading to an increment in the risk of bone fracture. After kidney transplantation, these bone alterations and others directly associated or not with changes in kidney function may persist, progress or transform into a different entity due to new pathogenetic mechanisms. With time, these alterations may improve or worsen depending to a large extent on the restoration of kidney function and correction of the metabolic abnormalities developed during the course of CKD. In this paper, we review the bone lesions that occur during both CKD progression and after kidney transplant and analyze the factors involved in their pathogenesis as a means to raise awareness of their complexity and interrelationship.

Is Adynamic Bone Always a Disease? Lessons from Patients with Chronic Kidney Disease

Renal osteodystrophy (ROD) is a common complication of end-stage kidney disease that often starts early with loss of kidney function, and it is considered an integral part in management of patients with chronic kidney disease (CKD). Adynamic bone (ADB) is characterized by suppressed bone formation, low cellularity, and thin osteoid seams. There is accumulating evidence supporting increasing prevalence of ADB, particularly in early CKD. Contemporarily, it is not very clear whether it represents a true disease, an adaptive mechanism to prevent bone resorption, or just a transitional stage. Several co-players are incriminated in its pathogenesis, such as age, diabetes mellitus, malnutrition, uremic milieu, and iatrogenic factors. In the present review, we will discuss the up-to-date knowledge of the ADB and focus on its impact on bone health, fracture risk, vascular calcification, and long-term survival. Moreover, we will emphasize the proper preventive and management strategies of ADB that are pivotal issues in managing patients with CKD. It is still unclear whether ADB is always a pathologic condition or whether it can represent an adaptive process to suppress bone resorption and further bone loss. In this article, we tried to discuss this hard topic based on the available limited information in patients with CKD. More studies are needed to be able to clearly address this frequent ROD finding.

Evaluation and Management of Primary Hyperparathyroidism: Summary Statement and Guidelines from the Fifth International Workshop

The last international guidelines on the evaluation and management of primary hyperparathyroidism (PHPT) were published in 2014. Research since that time has led to new insights into epidemiology, pathophysiology, diagnosis, measurements, genetics, outcomes, presentations, new imaging modalities, target and other organ systems, pregnancy, evaluation, and management. Advances in all these areas are demonstrated by the reference list in which the majority of listings were published after the last set of guidelines. It was thus, timely to convene an international group of over 50 experts to review these advances in our knowledge. Four Task Forces considered: 1. Epidemiology, Pathophysiology, and Genetics; 2. Classical and Nonclassical Features; 3. Surgical Aspects; and 4. Management. For Task Force 4 on the Management of PHPT, Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) methodology addressed surgical management of asymptomatic PHPT and non-surgical medical management of PHPT. The findings of this systematic review that applied GRADE methods to randomized trials are published as part of this series. Task Force 4 also reviewed a much larger body of new knowledge from observations studies that did not specifically fit the criteria of GRADE methodology. The full reports of these 4 Task Forces immediately follow this summary statement. Distilling the essence of all deliberations of all Task Force reports and Methodological reviews, we offer, in this summary statement, evidence-based recommendations and guidelines for the evaluation and management of PHPT. Different from the conclusions of the last workshop, these deliberations have led to revisions of renal guidelines and more evidence for the other recommendations. The accompanying papers present an in-depth discussion of topics summarized in this report. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Renal disease is a risk factor for complications and mortality after open reduction internal fixation of proximal humerus fractures

Background

Renal osteodystrophy predisposes renal disease patients to fracture. Proximal humerus fractures (PHFs) frequently undergo open reduction internal fixation (ORIF); however, the effect of renal disease on outcomes is unknown.

Methods

A retrospective review of the Nationwide Readmissions Database used International Classification of Diseases, 9th Revision, codes to identify patients who underwent ORIF for closed PHF from 2010 to 2014 with no renal disease, predialysis chronic renal disease (CRD), and end-stage renal disease (ESRD).

Results

A total of 85,433 patients were identified, including 5498 (6.4%) CRD and 636 (0.7%) ESRD. CRD and ESRD patients had increased age, comorbidities, and rates of Medicare insurance. After adjusting for differences, CRD and ESRD patients were at increased risk of any complication (odds ratio [OR] 2.48, 1.66), blood transfusion (OR 1.85, 3.31), respiratory complications (OR 1.14, 1.59), acute renal failure (OR 4.80, 1.67), systemic infection (OR 2.00, 3.14), surgical site infection (OR 1.52, 3.87), longer length of stay (7.1 and 12.9 days vs. 5.9 days), and higher cost ($21,669 and $35,413 vs. $20,394) during index hospitalization, as well as surgical site infection (OR 1.43, 3.03) and readmission (OR 1.61, 3.69) within 90 days of discharge, respectively, compared with no renal disease patients. During index hospitalization, CRD patients also had increased risk for periprosthetic fracture (OR 4.97) and cardiac complications (OR 1.47), whereas ESRD patients had increased risk of mortality (OR 5.79), wound complication (2.67), and deep vein thrombosis (OR 16.70).

Conclusion

These findings suggest renal patients are at increased risk for complications after PHF ORIF, highlighting the importance of close perioperative monitoring and appropriate patient selection in this population, including strong consideration of nonoperative management.

Influence of Renal Function on Pharmacokinetics, Pharmacodynamics, and Safety of a Single Dose of Romosozumab

We evaluated the pharmacokinetics, pharmacodynamics, and safety of a single subcutaneous dose of romosozumab 210 mg, a monoclonal antibody against sclerostin, in an open-label, parallel-group study in participants with severe (stage 4) renal impairment (RI; n = 8) or end-stage renal disease requiring hemodialysis (ESRD-RH; n = 8), or healthy participants with normal renal function (n = 8). Compared with the group with normal renal function, the mean romosozumab exposure was 31% and 43% higher as measured by C_max and AUC, respectively, in the severe RI group and similar to those in the ESRD-RH group. For all 3 groups, the maximum mean percent increase in procollagen type 1 N terminal propeptide (P1NP) and decrease in serum C-telopeptide (sCTX) levels from baseline were observed on day 15. Changes in P1NP and sCTX were of similar patterns in all 3 groups. The single dose of romosozumab 210 mg was well tolerated. Adverse events (AEs) were reported for 13 patients (7 patients with severe RI and 6 with ESRD-RH), with no deaths, AEs, or serious AEs leading to withdrawal. The incidence of subjects with postbaseline transient decreases in serum calcium (severe RI, n = 1; ESRD-RH, n = 5) and increases in intact parathyroid hormone (severe RI, n = 7; ESRD-RH, n = 7; healthy, n = 3) were greater in severe RI and ESRD-RH groups than in the healthy group. All reported events of hypocalcemia (severe RI, n = 1; ESRD-RH, n = 4) were asymptomatic. These results support the use of romosozumab without dose adjustment in patients with severe RI or ESRD-RH. This article is protected by copyright. All rights reserved.

Greater Carboxy-Methyl-Lysine Is Associated With Increased Fracture Risk in Type 2 Diabetes

Accumulation of advanced glycation end-products (AGE) in bone alters collagen structure and function. Fluorescent AGEs are associated with fractures but less is known regarding non-fluorescent AGEs. We examined associations of carboxy-methyl-lysine (CML), with incident clinical and prevalent vertebral fractures by type 2 diabetes (T2D) status, in the Health, Aging, and Body Composition cohort of older adults. Incident clinical fractures and baseline vertebral fractures were assessed. Cox regression was used to analyze the associations between serum CML and clinical fracture incidence, and logistic regression for vertebral fracture prevalence. At baseline, mean ± standard deviation (SD) age was 73.7 ± 2.8 and 73.6 ± 2.9 years in T2D (n = 712) and non-diabetes (n = 2332), respectively. Baseline CML levels were higher in T2D than non-diabetes (893 ± 332 versus 771 ± 270 ng/mL, p < 0.0001). In multivariate models, greater CML was associated with higher risk of incident clinical fracture in T2D (hazard ratio [HR] 1.49; 95% confidence interval [CI], 1.24-1.79 per 1-SD increase in log CML) but not in non-diabetes (HR 1.03; 95% CI, 0.94-1.13; p for interaction = 0.001). This association was independent of bone mineral density (BMD), glycated hemoglobin (hemoglobin A1c), weight, weight loss, smoking, cystatin-C, and medication use. CML was not significantly associated with the odds of prevalent vertebral fractures in either group. In conclusion, higher CML levels are associated with increased risk of incident clinical fractures in T2D, independent of BMD. These results implicate CML in the pathogenesis of bone fragility in diabetes. © 2021 American Society for Bone and Mineral Research (ASBMR).

Bone metabolism subgroups identified as hip fracture patients via clustering

PURPOSE

The aim of the study was to describe the bone metabolism status that underlies a hip fracture.

METHODS

Estimated glomerular filtration rate (e-GFR), calcium (Ca), phosphorus (P), total (ALP) and bone specific alkaline phosphatase (b-ALP), intact parathyroid hormone (i-PTH), 25-hydroxy-vitamin D (25OHD), total procollagen type I amino-terminal propeptide (PINP), and N-terminal peptide of collagen I (NTx), measured at admission in 272 hip fracture patients, were ex post analyzed by K-means clustering and principal component analysis and were evaluated by a clinician.

RESULTS

Four components, mainly consisting of b-ALP, PINP, ALP, and NTx; e-GFR and P; i-PTH and 25OHD; and Ca explained about 70% of the variability. A total of 184 patients clustered around a centroid (A) with low 25OHD (13.2 ng/ml), well-preserved kidney function (e-GFR=67.19 ml/min/1.73m²), normal Ca, P, i-PTH and bone markers, with the exception of slightly increased NTx (24.82nMBCE). Cluster B (n=70) had increased i-PTH (93.38 pg/ml), moderately decreased e-GFR, very low 25OHD (8.68 ng/dl), and high bone turnover (b-ALP 28.46 U/L, PINP 69.87 ng/ml, NTx 31.3nMBCE). Cluster C (n=17) also had hyperparathyroidism (80.35 pg/ml) and hypovitaminosis D (9.15 ng/ml), low e-GFR(48.89 ml/min/1.73m²), and notably high ALP (173 U/L) and bone markers (b-ALP 44.64 U/L, PINP 186.98 ng/ml, NTx 38.28nMBCE). According to the clinician, 62 cases clearly had secondary hyperparathyroidism.

CONCLUSIONS

Based on serum measurements, the dominant patterns of bone metabolism were normal bone turnover with high normal NTx, and secondary hyperparathyroidism related to chronic kidney disease and hypovitaminosis D. The bone formation markers, e-GFR, NTx, and P composed the most important factors.

Premature Aging in Chronic Kidney Disease: The Outcome of Persistent Inflammation beyond the Bounds

Over the last hundred years, life expectancy in developed countries has increased because of healthier living habits and the treatment of chronic pathologies causing premature aging. Aging is an inexorable, time-dependent, multifactorial process characterized by a series of progressive and irreversible physiological changes associated with loss of functional, psychological, and social capabilities. Numerous factors, such as oxidative stress, inflammation, and cellular senescence, and an irreversible geriatric syndrome known as frailty, contribute to human body deterioration in aging. The speed of aging may differ between individuals depending on the presence or absence of multiple factors (genetic and/or environment) and the subsequent misbalance of homeostasis, together with the increase of frailty, which also plays a key role in developing chronic diseases. In addition, pathological circumstances have been reported to precipitate or accelerate the aging process. This review investigated the mechanisms involved in the developing pathologies, particularly chronic kidney disease, associated with aging.

Hip Fracture Risk in Elderly With Non-End-Stage Chronic Kidney Disease: A Fall Related Analysis

BACKGROUND

The aim of this study was to evaluate the risk of fracture as a consequence of trauma and its association with kidney function status in a cohort of elderly patients.

METHODS

This is an observational, cross-sectional study. We evaluated all fall-related trauma of patients ≥ 65 years in the emergency department (ED) between 2016 and 2018. According to CDK-EPI formula, we stratified the study population in different stages of chronic kidney disease (CKD) for glomerular filtrate rate (GFR) ≥ 15 and < 60, not on hemodialysis. The hip fracture rate was adjusted at multivariate analysis for age, sex, comorbid conditions, and CKD status.

RESULTS

We enrolled 5620 patients: 3482 patients had GFR ≥60, 1045 had GFR ≥45 and <60, 722 had GFR ≥30 and <45, and 371 had GFR ≥15 and <30. We recorded 636 (11.3%) hip fractures. After adjusting for significant covariates (age, sex, known osteoporosis, osteoporosis therapy, anemia, and dementia), patients with GFR ≥ 45 and <60 and GFR ≥30 and <45 exhibited an increased risk of femur fracture (odds ratio 2.01 [1.36-2.97] and 1.64 [1.08-2.48], respectively). Patients with GFR ≥15 and <30 had a higher risk of fracture, although not reaching statistical significance.

CONCLUSIONS

Our study confirms that patients with non-end stage CKD have an increased risk of femur fracture after a fall. Our data supports the hypothesis that this risk could be associated with increased bone fragility in CKD patients. Active osteoporosis therapy was found to be an effective preventive factor in our cohort.

The Influence of Dietary Interventions on Chronic Kidney Disease-Mineral and Bone Disorder (CKD-MBD)

Chronic kidney disease is a health problem whose prevalence is increasing worldwide. The kidney plays an important role in the metabolism of minerals and bone health and therefore, even at the early stages of CKD, disturbances in bone metabolism are observed. In the course of CKD, various bone turnover or mineralization disturbances can develop including adynamic hyperparathyroid, mixed renal bone disease, osteomalacia. The increased risk of fragility fractures is present at any age in these patients. Nutritional treatment of patients with advanced stages of CKD is aiming at prevention or correction of signs, symptoms of renal failure, avoidance of protein-energy wasting (PEW), delaying or prevention of the occurrence of mineral/bone disturbances, and delaying the start of dialysis. The results of studies suggest that progressive protein restriction is beneficial with the progression of renal insufficiency; however, other aspects of dietary management of CKD patients, including changes in sodium, phosphorus, and energy intake, as well as the source of protein and lipids (animal or plant origin) should also be considered carefully. Energy intake must cover patients' energy requirement, in order to enable correct metabolic adaptation in the course of protein-restricted regimens and prevent negative nitrogen balance and protein-energy wasting.

Differentiating the causes of adynamic bone in advanced chronic kidney disease informs osteoporosis treatment

Patients with chronic kidney disease (CKD) have an increased fracture risk because of impaired bone quality and quantity. Low bone mineral density predicts fracture risk in all CKD stages, including advanced CKD (CKD G4-5D). Pharmacological therapy improves bone mineral density and reduces fracture risk in moderate CKD. Its efficacy in advanced CKD remains to be determined, although pilot studies suggest a positive effect on bone mineral density. Currently, antiresorptive agents are the most commonly prescribed drugs for the prevention and therapy of osteoporosis. Their use in advanced CKD has been limited by the lack of large clinical trials and fear of causing kidney dysfunction and adynamic bone disease. In recent decades, adynamic bone disease has evolved as the most predominant form of renal osteodystrophy, commonly associated with poor outcomes, including premature mortality and progression of vascular calcification. Evolving evidence indicates that reduction of bone turnover by parathyroidectomy or pharmacological therapies, such as calcimimetics and antiresorptive agents, are not associated with premature mortality or accelerated vascular calcification in CKD. In contrast, chronic inflammation, oxidative stress, malnutrition, and diabetes can induce low bone turnover and associate with poor prognosis. Thus, the conditions causing suppression of bone turnover rather than the low bone turnover per se may account for the perceived association with outcomes. Anabolic treatment, in contrast, has been suggested to improve turnover and bone mass in patients with advanced CKD and low bone turnover; however, uncertainty about safety even exceeds that of antiresorptive agents. Here, we critically review the pathophysiological concept of adynamic bone disease and discuss the effect of low bone turnover on the safety and efficacy of anti-osteoporosis pharmacotherapy in advanced CKD.

Bone Fragility Fractures in CKD Patients

Chronic kidney diseases (CKD) are associated with mineral and bone diseases (MBD), including pain, bone loss, and fractures. Bone fragility related to CKD includes the risk factors observed in osteoporosis in addition to those related to CKD, resulting in a higher risk of mortality related to fractures. Unawareness of such complications led to a poor management of fractures and a lack of preventive approaches. The current guidelines of the Kidney Disease Improving Global Outcomes (KDIGO) recommend the assessment of bone mineral density if results will impact treatment decision. In addition to bone density, circulating biomarkers of mineral, serum bone turnover markers, and imaging techniques are currently available to evaluate the fracture risk. The purpose of this review is to provide an overview of the epidemiology and pathogenesis of CKD-associated bone loss. The contribution of the current tools and other techniques in development are discussed. We here propose a current view of how to better predict bone fragility and the therapeutic options in CKD.

Home-based exercise and bone mineral density in peritoneal dialysis patients: a randomized pilot study

BACKGROUND

The prevalence of osteopenia and osteoporosis is higher in patients with chronic kidney disease than that in the general population. Although physical exercise prevents bone loss in hemodialysis (HD) patients, previous studies have not focused on peritoneal dialysis (PD) patients. Therefore, we aimed to evaluate the effects of home-based exercise on bone mineral density (BMD) in patients with PD.

METHODS

Stable outpatients undergoing PD were randomly assigned to the intervention group (n = 26; male, 20; median age, 66 years) or usual-care group (n = 27; male, 21; median age, 64 years). Patients in the intervention group performed home-based exercises (resistance exercise, stretching, and aerobic exercise such as walking) for 6 months, whereas those in the usual-care group performed stretching and their usual physical activity. Based on dual X-ray absorptiometry, the primary outcomes were the BMD data of the lumbar spine and proximal femoral neck. Secondary outcomes included physical function and physical activity. Pre- and post-intervention values were compared.

RESULTS

There was no significant within-group change in the BMD of the lumbar spine, femoral neck, and hip after 6 months of the exercise program. The intervention group had significantly improved 30-s chair-stand test, 6-min walk test, and physical activity results.

CONCLUSIONS

Home-based exercises in patients with PD did not improve BMD at any of the sites evaluated. Improvement in physical function and physical activity may reduce the risk of falls in patients with PD.

TRIAL REGISTRATION

UMIN Clinical Trials Registry, UMIN000041678 . Registered September 4, 2020; retrospectively registered.

Denosumab Safety and Efficacy Among Participants in the FREEDOM Extension Study With Mild to Moderate Chronic Kidney Disease

CONTEXT

The effects of long-term exposure to denosumab in individuals with renal insufficiency are unknown.

OBJECTIVE

This post hoc analysis evaluates the long-term safety and efficacy of denosumab in individuals with mild-to-moderate chronic kidney disease (CKD) (stages 2 and 3) using data from the pivotal phase 3, double-blind, 3-year FREEDOM (NCT00089791) and open-label, 7-year extension (NCT00523341) studies.

PARTICIPANTS AND METHODS

Women age 60 to 90 years with a bone mineral density (BMD) T-score of less than -2.5 to greater than -4.0 at the total hip or lumbar spine were randomly assigned 1:1 to receive denosumab 60 mg subcutaneously every 6 months (long-term arm) or placebo (cross-over arm) in FREEDOM; eligible participants could enroll in the extension to receive denosumab 60 mg subcutaneously every 6 months. Change in estimated glomerular filtration rate (eGFR) from study baseline and annualized rates of fracture and adverse events (AEs) were the main outcome measures.

RESULTS

Most participants (1259/1969 [64%] long-term arm; 1173/1781 [66%] crossover arm) with baseline CKD stage 2 or 3 remained within the same CKD subgroup at study completion; less than 3% progressed to CKD stage 4. Participants in all eGFR subgroups showed similar, persistent BMD gains over time and a low incidence of fractures. The percentage of participants reporting serious AEs was similar among renal subgroups (normal, CKD stage 2, CKD stage 3a, CKD stage 3b) both for the long-term (54% vs 52% vs 57% vs 58%) and crossover (43% vs 42% vs 43% vs 68%) arms, except CKD stage 3b subgroup, crossover arm.

CONCLUSION

The safety and efficacy of denosumab did not differ among participants with mild to moderate CKD.

Executive summary of clinical practice guide on fracture risk in lifestyle diseases

Accumulating evidence has shown that patients with lifestyle diseases such as type 2 diabetes mellitus, chronic kidney disease, and chronic obstructive pulmonary disease are at increased risk of osteoporotic fracture. Fractures deteriorate quality of life, activities of daily living, and mortality as well as a lifestyle disease. Therefore, preventing fracture is an important issue for those patients. Although the mechanism of the lifestyle diseases-induced bone fragility is still unclear, not only bone mineral density (BMD) reduction but also bone quality deterioration are involved in it. Because fracture predictive ability of BMD and FRAX^® is limited, especially for patients with lifestyle diseases, the optimal management strategy should be established. Thus, when the intervention of the lifestyle diseases-induced bone fragility is initiated, the deterioration of bone quality should be taken into account. We here review the association between lifestyle diseases and fracture risk and proposed an algorism of starting anti-osteoporosis drugs for patients with lifestyle diseases.

Trabecular bone score in patients with chronic kidney disease

Patients with chronic kidney disease have high risk of osteoporotic fractures. Lower trabecular bone score (TBS) was associated with poorer kidney function and higher fracture risk when kidney function was normal. Addition of TBS to The Fracture Risk Assessment Tool with bone mineral density did not improve fracture risk prediction.

INTRODUCTION

We sought to determine whether trabecular bone score (TBS) either independently or adjusted for The Fracture Risk Assessment Tool (FRAX) could predict risk of major osteoporotic fractures (MOFs) in a large population-based sample of patients with all stages of chronic kidney disease (CKD).

METHODS

We used population-based administrative databases to identify patients above age 20 years who had dual-energy X-ray absorptiometry (DXA) scan and serum creatinine measured within 1 year, during the years 2005 to 2010. Patients were excluded if they were on dialysis or had a functioning renal transplant. We stratified patients by estimated glomerular filtration rate (eGFR). We collected femoral neck bone mineral density (BMD), lumbar spine TBS, incident major osteoporotic fractures (MOF) and hip fractures, and other clinical characteristics.

RESULTS

Among 8289 patients, there were 6224 (75.1%) with eGFR ≥ 60 mL/min/1.73 m², 1624 (19.6%) with eGFR 30-60 mL/min/1.73 m², and 441 (5.3%) with eGFR < 30 mL/min/1.73 m². There were 593 patients (7.2%) with MOFs and 163 (2.0%) with hip fractures. Lower TBS score was associated with increased risk of MOF and hip fractures across all eGFR strata in unadjusted Cox proportional hazards models but after adjusting for FRAX with BMD, lower TBS was only statistically significant for MOF prediction for eGFR ≥ 60 mL/min/1.73 m².

CONCLUSION

Lower TBS scores were associated with lower eGFR and increased fracture risk in patients with eGFR ≥ 60 mL/min/1.73 m². However, the addition of TBS to the FRAX score with BMD did not significantly improve fracture risk prediction in patients with CKD.

The risk of new fragility fractures in patients with chronic kidney disease and hip fracture-a population-based cohort study in the UK

Chronic kidney disease (CKD) is a risk factor for fractures. However, in hip fracture patients, CKD G3-G5 was associated with a higher mortality risk and not associated with a higher risk of subsequent non-hip fractures compared to eGFR > 60 ml/min. The higher mortality risk may, as competing risk, explain our findings.

INTRODUCTION

Chronic kidney disease (CKD) is a known risk factor for fragility fractures. Patients aged 50+ with a recent fragility fracture have an increased risk of subsequent fractures. Our aim was to evaluate the association between CKD stages G3-G5 versus estimated glomerular filtration rate (eGFR) > 60 ml/min and the risk of a new non-hip fracture or fragility fracture in patients with a first hip fracture.

METHODS

Population-based cohort study using the UK general practices in the Clinical Practice Research Datalink. Associations between CKD stage and first subsequent fracture were determined using Cox proportional hazard analyses to estimate hazard ratios (HRs). To explore the potential competing risk of mortality, cause-specific (cs) HRs for mortality were estimated.

RESULTS

CKD G3-G5 was associated with a lower risk of any subsequent non-hip fracture (HR: 0.90, 95%CI: 0.83-0.97), but not with the risk of subsequent major non-hip fragility fracture. CKD G3-G5 was associated with a higher mortality risk (cs-HR: 1.05, 95%CI: 1.01-1.09). Mortality risk was 1.5- to 3-fold higher in patients with CKD G4 (cs-HR: 1.50, 95%CI: 1.38-1.62) and G5 (cs-HR: 2.93, 95%CI: 2.48-3.46) compared to eGFR > 60 ml/min.

CONCLUSIONS

The risk of a subsequent major non-hip fragility fractures following hip fracture was not increased in patients with CKD G3-G5 compared to eGFR > 60 ml/min. Mortality risk was higher in both hip fracture and non-hip fracture patients with CKD G4 and G5. The higher mortality risk may, as competing risk, explain our main finding of no increased or even decreased subsequent fracture risk after a hip fracture in patients with CKD G3-G5.

The association between chronic kidney disease, falls, and fractures: a systematic review and meta-analysis

Patients with chronic kidney disease (CKD) are more likely to experience falls and fractures due to renal osteodystrophy and the high prevalence of risk factors for falls. However, it is not well established how great the risk is for falls and fractures for the different stages of CKD compared to the general population. The objective of this systematic review and meta-analysis was to assess whether, and in which degree, CKD was associated with falls and fractures in adults. A systematic search in PubMed, Embase, CINAHL, and The Cochrane Library was performed on 7 September 2018. All retrospective, cross-sectional, and longitudinal studies of adults (18 years of older) that studied the association between CKD, fractures, and falls were included. Additional studies were identified by cross-referencing. A total of 39 publications were included, of which two publications assessed three types of outcome and four publications assessed two types of outcome. Ten studies focused on accidental falling; seventeen studies focused on hip, femur, and pelvis fractures; seven studies focused on vertebral fractures; and thirteen studies focused on any type of fracture without further specification. Generally, the risk of fractures increased when kidney function worsened, with the highest risks in the patients with stage 5 CKD or dialysis. This effect was most pronounced for hip fractures and any type of fractures. Furthermore, results on the association between CKD and accidental falling were contradictory. Compared to the general population, fractures are highly prevalent in patients with CKD. Besides more awareness of timely fracture risk assessment, there also should be more focus on fall prevention.

Bone Health in Glomerular Kidney Disease

PURPOSE OF REVIEW

To summarize the literature regarding alterations in bone health in patients with glomerular kidney disease and highlight areas in need of additional investigation.

RECENT FINDINGS

There is mounting evidence that children and adults with glomerular conditions, with or without compromised kidney function, comprise a distinct subgroup of patients with unique risk factors for altered bone health. Patients with glomerular kidney disease are exposed to both disease-related and treatment-related factors that affect bone structure and function. In addition to chronic kidney disease-related risk factors for impaired bone health, high rates of exposure to osteotoxic medications, varying degrees of systemic inflammation, and altered vitamin D metabolism may contribute to compromised bone health in individuals with glomerular disease. Further study is needed to better understand these risk factors and the complex interaction between the immune system and bone cells in glomerular disease.

Living Arrangements, Offspring Migration, and Health of Older Adults in Rural China: Revelation From Biomarkers and Propensity Score Analysis

Objective: We examine the combined effects of living arrangements and outmigration of adult children on rural older adults' health profiles, measured by biomarker data from the China Health and Retirement Longitudinal Study 2011. Method: We employ biomarker data and propensity score analysis which allows us to effectively deal with selection issues that are commonly observed in the literature. Results: We show complex health implications of living arrangements and offspring migration. Living in a traditional multigenerational household has limited health benefits to older adults. However, older parents of migrants who live in a multigenerational household have better fitness in blood pressure. Their advantage over parents of migrants in other living arrangements suggests added benefits of the presence of grandchildren. Discussion: This study bridges the living arrangement and migration literature on health by showing that health effects of adult children's migration on older adults are contingent upon their living arrangements.

Falls and Fall-Related Injuries Among US Adults Aged 65 or Older With Chronic Kidney Disease

Introduction

Falls are among the leading causes of injury and death among adults aged 65 or older. People with chronic kidney disease (CKD) are at increased risk of falling and of having a serious injury from falls. However, information is limited about risk factors for falls and fall-related injuries among people with CKD.

Methods

We performed a secondary analysis of 157,753 adults (6.1% with CKD) aged 65 or older surveyed in the 2014 Behavioral Risk Factor Surveillance System.

Results

People with CKD were at increased risk of falls (odds ratio [OR] = 1.81; 95% confidence interval [CI], 1.63–2.01) and fall-related injuries (OR = 1.50; 95% CI, 1.27–1.78) even after adjusting for differences in demographic characteristics, health conditions, and lifestyle factors (P < .05 for all). Among people with CKD, women, people diagnosed with diabetes, diabetes duration, and arthritis were all significant predictors of falls and fall-related injuries (P < .05 for all). Lifestyle factors, such as engaging in recent exercise (adjusted odds ratio [AOR] = 0.68; 95% CI, 0.56–0.81) and limited physical function (assessed as difficulty in climbing stairs) (AOR = 2.84; 95% CI, 2.30–3.44), were most closely associated with falls and fall-related injuries.

Conclusion

Adults aged 65 or older with CKD were at increased risk of falling and of suffering an injury as a result of a fall compared with adults in the same age range without CKD. Potentially modifiable factors such as physical function and recent exercise were most closely related to reduced risk for falls and fall-related injuries and may be an appropriate target for fall prevention and rehabilitation programs in people with CKD.

Osteoporosis, bone mineral density and CKD-MBD complex (I): Diagnostic considerations

Osteoporosis (OP) and chronic kidney disease (CKD) independently influence bone and cardiovascular health. A considerable number of patients with CKD, especially those with stages 3a to 5D, have a significantly reduced bone mineral density leading to a high risk of fracture and a significant increase in associated morbidity and mortality. Independently of classic OP related to age and/or gender, the mechanical properties of bone are also affected by inherent risk factors for CKD ("uraemic OP"). In the first part of this review, we will analyse the general concepts regarding bone mineral density, OP and fractures, which have been largely undervalued until now by nephrologists due to the lack of evidence and diagnostic difficulties in the context of CKD. It has now been proven that a reduced bone mineral density is highly predictive of fracture risk in CKD patients, although it does not allow a distinction to be made between the causes which generate it (hyperparathyroidism, adynamic bone disease and/or senile osteoporosis, etc.). Therefore, in the second part, we will analyse the therapeutic indications in different CKD stages. In any case, the individual assessment of factors which represent a higher or lower risk of fracture, the quantification of this risk (i.e. using tools such as FRAX^®) and the potential indications for densitometry in patients with CKD could represent an important first step pending new clinical guidelines based on randomised studies which do not exclude CKD patients, all the while avoiding therapeutic nihilism in an area of growing importance.

Hip fracture incidence and mortality in chronic kidney disease: the GLOMMS-II record linkage cohort study

BACKGROUND

Individuals on renal replacement therapy (RRT) have increased fracture risk, but risk in less advanced chronic kidney disease (CKD) is unclear.

OBJECTIVE

To investigate CKD associations with hip fracture incidence and mortality.

DESIGN

Record linkage cohort study Grampian Laboratory Outcomes Mortality and Morbidity Study II.

SETTING

Single health region in Scotland.

PARTICIPANTS

All individuals (≥15 years) with sustained CKD stages 3-5 and those on RRT, and a 20% random sample of those with normal renal function, in the resident population in 2003.

OUTCOME MEASURES

Outcomes were (1) incident hip fracture measured with (A) admissions or (B) deaths, with at least 5.5 years follow-up and (2) post-hip fracture mortality. Unadjusted and adjusted, incident rate ratios (IRRs) and mortality rate ratios were calculated using Poisson regression.

RESULTS

Of 39 630 individuals identified in 2003 (41% males, mean age 63.3 years), 19 537 had CKD stages 3-5, 345 were on RRT and 19 748 had normal estimated glomerular filtration rate (eGFR). Hip fracture incidence, measured by admissions, was increased in CKD stages 3-5 (compared with normal eGFR), both overall (adjusted IRR 1.49 (95% CI 1.24 to 1.79)) and for individual CKD stages 3a, 3b and 4. Hip fracture incidence, measured using deaths, was increased in those with CKD stages 3b and 4. Post-hip fracture mortality was only increased in CKD stage 4. There was only a small number of individuals and events for CKD stage 5, resulting in insufficient statistical power.

CONCLUSION

Hip fracture incidence was higher in CKD stages 3-5 compared with normal eGFR. Post-hip fracture mortality was only increased in CKD stage 4. Reducing hip fracture incidence in CKD through regular fall and fracture risk review should reduce overall deaths after hip fracture in the population.

Skeletal manifestations of renal disease in childhood

PURPOSE OF REVIEW

This review summarizes recent findings on musculoskeletal health in three chronic renal conditions of childhood: chronic kidney disease stages 2-5D, nephrotic syndrome, and urolithiasis. Findings with important clinical implications warranting further investigation are highlighted.

RECENT FINDINGS

Recent cohort studies have demonstrated a high burden of fracture and progressive deficits of cortical bone in children with chronic kidney disease. Lower cortical density is associated with incident fracture and may be an important therapeutic target. Parathyroid hormone and calcium are independent correlates of cortical density, and modifiable factors for fracture include parathyroid hormone and phosphate binder use. Children with nephrotic syndrome, even with normal renal function, have evidence of abnormal bone metabolism and structure, and vitamin D deficiency may be an important modifiable risk factor in this population. Urolithiasis has been associated with reduced bone mineral density and is increasingly common in children and adolescents. Population-based data found a significantly increased risk of fracture in adolescent males and young women.

SUMMARY

Recent findings substantiate concern regarding the particular vulnerability of the growing skeleton to chronic renal disease. Studies are needed to determine how to optimize assessment and management of bone health in children with these conditions, particularly in terms of calcium and vitamin D requirements, with the goal of improving childhood bone accrual for lifelong fracture prevention.

Association between the age-related decline in renal function and lumbar spine bone mineral density in healthy Chinese postmenopausal women

OBJECTIVES

The relationship between the decline of renal function and bone mineral density (BMD) in healthy populations is not well-researched. The aim of this study was to investigate the association between the age-related decline in renal function and lumbar spine BMD (LBMD) in a community-based cross-sectional study of 390 healthy postmenopausal women (mean age 62.97 ± 8.79 years) from Shenyang, China.

METHODS

Dual-energy x-ray absorptiometry was used to measure LBMD. Estimated glomerular filtration rate (eGFR) was calculated using a modified Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation for Asians and the CKD-EPI serum creatinine-cystatin c equation. Pearson's correlation analysis and binary logistic regression were used to evaluate associations.

RESULTS

The eGFR-ASIA and eGFR-Scys were positively correlated with LBMD (r = 0.120 and r = 0.108, respectively). After adjustments for numerous potential confounders, the odds ratio for participants with LBMD decline in eGFR-ASIA quartile 3 group and 4 group were 2.45 (95% confidence interval [CI] 1.12-5.38, P < 0.05) and 3.89 (95% CI 1.55-9.76, P < 0.01), respectively, with P = 0.003 for the trend in eGFR-ASIA compared with the lowest quartile 1 group of eGFR-ASIA, where the odds ratio of eGFR-Scys for the quartile of 3 and 4 groups were 2.47 (95% CI 1.09-5.62, P < 0.05) and 2.63 (95% CI 1.10-6.29, P < 0.05), respectively, with P = 0.016 for the trend in eGFR-Scys compared with the lowest quartile 1 group of eGFR-Scys.

CONCLUSIONS

The renal function decline was independently associated with decreased LBMD, and it was possible that the age-related decline in kidney function was an independent risk factor for decreased LBMD in healthy Chinese postmenopausal women.

Management of Osteoporosis in Chronic Kidney Disease

Chronic kidney disease (CKD) patients with coexisting osteoporosis are becoming common. Many of the therapeutic agents used to treat osteoporosis are known to be affected by the renal function. It is generally thought that osteoporosis in G1 to G3 CKD patients can be treated as in non-CKD patients with osteoporosis. In stage 4 or more advanced CKD patients and CKD patients on dialysis with osteoporosis, however, bisphosphonates must be used with caution, bearing in mind the potential development of such disorders as adynamic bone disease. The use of vitamin D preparations in low doses is relatively safe. In postmenopausal women, raloxifene must be administered with caution. When using denosumab, the serum calcium concentrations should be monitored carefully to prevent the development of hypocalcemia, and active vitamin D preparations should be administered concomitantly. The present article provides an overview of the management of osteoporosis in CKD patients.

Changing bone patterns with progression of chronic kidney disease

It is commonly held that osteitis fibrosa and mixed uremic osteodystrophy are the predominant forms of renal osteodystrophy in patients with chronic kidney disease. Osteitis fibrosa is a high-turnover bone disease resulting mainly from secondary hyperparathyroidism, and mixed uremic osteodystrophy is in addition characterized by a mineralization defect most often attributed to vitamin D deficiency. However, there is ancient and more recent evidence that in early chronic kidney disease stages adynamic bone disease characterized by low bone turnover occurs first, at least in a significant proportion of patients. This could be due to the initial predominance of bone turnover-inhibitory conditions such as resistance to the action of parathyroid hormone (PTH), reduced calcitriol levels, sex hormone deficiency, diabetes, and, last but not least, uremic toxins leading to repression of osteocyte Wnt/β-catenin signaling and increased expression of Wnt antagonists such as sclerostin, Dickkopf-1, and sFRP4. The development of high-turnover bone disease would occur only later on, when serum PTH levels are able to overcome peripheral PTH resistance and the other inhibitory factors of bone formation. Whether FGF23 and Klotho play a direct role in the transition from low- to high-turnover bone disease or participate only indirectly via regulating PTH secretion remains to be seen.

Safety and effectiveness of daily teriparatide for osteoporosis in patients with severe stages of chronic kidney disease: post hoc analysis of a postmarketing observational study

Teriparatide (recombinant 1-34 N-terminal sequence of human parathyroid hormone) for the treatment of osteoporosis should be prescribed with caution in patients with severe stages of chronic kidney disease (CKD). However, in clinical settings, physicians and surgeons who treat such patients have few available options. We sought to further explore the safety and effectiveness of teriparatide for the treatment of osteoporosis in Japanese patients with severe stages of CKD. This was a post hoc analysis of a postmarketing surveillance study that included patients with osteoporosis at high risk of fracture and stage 4 or 5 CKD. Patients received subcutaneous teriparatide 20 μg daily for up to 24 months. Safety profiles were assessed by physician-reported adverse drug reactions (ADRs). Effectiveness was assessed by measuring bone formation (via procollagen type 1 N-terminal propeptide [P1NP]), bone mineral density (BMD), and the incidence of clinical vertebral or nonvertebral fragility fractures. A total of 33 patients with severe stages of CKD (stage 4, n=30; stage 5, n=3) were included. All patients were female, and 81.8% had a history of previous fracture. No serious ADRs were recorded; a total of 4 ADRs were recorded for 4 of 33 patients. Increases in BMD and P1NP levels were observed both overall and in most individual patients. New fractures occurred in 1 patient with stage 5 CKD, but not in patients with stage 4 CKD. In this post hoc analysis conducted in Japan, teriparatide appeared to be effective for the treatment of osteoporosis in elderly female patients with severe stages of CKD, and no new safety concerns were observed.

Trabecular Bone Score and Incident Fragility Fracture Risk in Adults with Reduced Kidney Function

BACKGROUND AND OBJECTIVES

Trabecular bone score is a gray-level textural measure obtained from dual energy x-ray absorptiometry lumbar spine images that provides information independent of areal bone mineral density. The association between trabecular bone score and incident fractures in adults with reduced kidney function and whether this association differs from that of adults with normal kidney function are unknown.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We included 1426 participants ages ≥40 years old (mean age of 67 years) in the community-based Canadian Multicentre Osteoporosis Study. We stratified participants at cohort entry (2005-2008) by eGFR (eGFR<60 ml/min per 1.73 m2 [n=199; 72.4% stage 3a, 25.1% stage 3b, and 2.5% stage 4] versus ≥60 ml/min per 1.73 m2 [n=1227]). Trabecular bone score was obtained from lumbar spine (L1-L4) dual energy x-ray absorptiometry images, with a lower trabecular bone score representing worse bone structure. Over an average of 4.7 years follow-up (maximum follow-up of 5 years), we documented incident fragility (low-trauma) fracture events (excluding craniofacial, foot, and hand sites). We used a modified Kaplan-Meier estimator to determine the 5-year probability of fracture. Cox proportional hazard regression per SD lower trabecular bone score expressed the gradient of fracture risk.

RESULTS

Individuals with an eGFR<60 ml/min per 1.73 m2 who had a trabecular bone score value below the median (<1.277) had a significantly higher 5-year fracture probability than those above the median (18.1% versus 6.2%; P=0.01). The association between trabecular bone score and fracture was independent of bone mineral density and other clinical risk factors in adults with reduced and normal kidney function (adjusted hazard ratio per SD lower trabecular bone score: eGFR<60 ml/min per 1.73 m2: adjusted hazard ratio, 1.62; 95% confidence interval, 1.04 to 2.51; eGFR≥60 ml/min per 1.73 m2: adjusted hazard ratio, 1.44; 95% confidence interval, 1.13 to 1.83).

CONCLUSIONS

Lower lumbar spine trabecular bone score is independently associated with a higher fracture risk in adults with reduced kidney function. Additional study is needed to examine the association between trabecular bone score and fractures in individuals with diagnosed CKD-mineral and bone disorder.

Hip Fracture in Patients With Non-Dialysis-Requiring Chronic Kidney Disease

Patients with end-stage renal disease (ESRD) are at a high risk for hip fracture. Little is known about the risk for, and consequences of, hip fracture among patients with non-dialysis-requiring chronic kidney disease (CKD). We examined the incidence of hip fracture, in-hospital mortality, length of stay, and costs among patients with ESRD, non-dialysis-requiring CKD, and normal or near normal kidney function. Using the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample, a nationally representative database, we identified hospitalizations for hip fracture in 2010. We incorporated data from the United States Renal Data System (USRDS) and the US census to calculate population-specific rates. Age-standardized incidence of hip fracture was highest among patients with ESRD (3.89/1000 person-years), followed by non-dialysis-requiring CKD (1.81/1000 persons) and patients with normal or near normal kidney function (1.18/1000 persons). In-hospital mo rtality (odds ratio [OR] = 1.69, 95% confidence interval [CI] 1.46 to 1.96), lengths of stay (median [10th, 90th percentiles] 5 [3 to 11] versus 5 [3 to 10] days) and costs (median $14,807 versus $13,314) were significantly higher in patients with non-dialysis-requiring CKD relative to patients with normal or near normal kidney function. In summary, non-dialysis-requiring CKD is associated with higher age-standardized rates of hip fracture and post-hip fracture mortality and higher resource utilization. © 2016 American Society for Bone and Mineral Research.

Hyponatremia: incidence, risk factors, and consequences in the elderly in a home-based primary care program

Aims: To determine the incidence, risk factors, etiology, and associations of hyponatremia in community-dwelling elderly with geriatric morbidity and mortality. Materials: Elderly participants of a single center home-based primary care program were included. Method: Retrospective chart review was conducted on demographic and clinical variables, comorbid diseases, frailty by Fried criteria and biochemical tests over a 1-year period. Primary outcome measure was a composite of falls, fractures due to falls, and hospitalization witnessed within the first year of enrollment into the program. Secondary outcome was all-cause mortality. Results: The study population (n = 608) had a mean age of 84.3 ± 9.3 years and was largely female (77.1%) and African-American (89.5%). Mean follow-up was 41.5 months. Frailty was seen in 44.4%. Incidence of all-cause mortality was 26.9%. Initial hyponatremia occurred in 8.71% (n = 53), and persistent hyponatremia (> 6 months of low serum sodium) in 4.1% (n = 25) of the study population. The major causes of hyponatremia included multiple potential causes, idiopathic syndrome of inappropriate anti-diuretic hormone (SIADH) and medications (thiazides and selective serotonin reuptake inhibitor (SSRI)). Primary outcome was independently associated with frailty (Odds ratio (OR) of 2.33) and persistent but not initial hyponatremia (OR 3.52). Secondary outcome was independently associated with age > 75 years (OR 2.88) and Afro-American race (OR 2.09) only but not to frailty or hyponatremia. Conclusions: Hyponatremia is common in home-bound elderly patients and its persistence independently contributes to falls, fractures, and hospitalization but not mortality. Our study highlights a new association of hyponatremia with frailty and underscores the need to study time-dependent association of hyponatremia with epidemiological outcomes.

Bone Density Is Directly Associated With Glomerular Filtration and Metabolic Acidosis but Do Not Predict Fragility Fractures in Men With Moderate Chronic Kidney Disease

Hyperparathyroidism, vitamin D deficiency, increased fibroblast growth factor-23 (FGF-23), and metabolic acidosis promote bone fragility in chronic kidney disease (CKD). Although useful in predicting fracture risk in the general population, the role of dual-energy X-ray absorptiometry (DXA) in CKD remains uncertain. This cross-sectional study included 51 men aged 50-75 yr with moderate CKD. The stage 4 CKD patients had higher levels of parathyroid hormone (p<0.001), FGF-23 (p=0.029), and lowest 25-hydroxyvitamin D (p=0.016), bicarbonate (p<0.001), total femur (p=0.003), and femoral neck (p=0.011) T-scores compared with stage 3 CKD patients. Total femur and femoral neck T-scores were directly correlated with serum bicarbonate (p=0.003, r=0.447 and p=0.005, r=0.427, respectively) and estimated glomerular filtration rate (p=0.024, r=0.325 and p=0.003, r=0.313, respectively) but were not significantly associated with parathyroid hormone, 25-hydroxyvitamin D, or FGF-23. Only 3.9% of the participants had osteoporosis on DXA scan, whereas 31.4% reported a low-impact fracture. Our data point to a pivotal role of metabolic acidosis for bone impairment and to the inadequacy of DXA to evaluate bone fragility in CKD patients.

Compromised vertebral structural and mechanical properties associated with progressive kidney disease and the effects of traditional pharmacological interventions

BACKGROUND/AIMS

Patients with chronic kidney disease mineral and bone disorder (CKD-MBD) have a significantly higher vertebral and non-vertebral fracture risk than the general population. Several preclinical models have documented altered skeletal properties in long bones, but few data exist for vertebral bone. The goal of this study was to examine the effects of progressive CKD on vertebral bone structure and mechanics and to determine the effects of treatment with either bisphosphonates or anti-sclerostin antibody in groups of animals with high or low PTH.

METHODS

Animals with progressive kidney disease were left untreated, treated with calcium to lower PTH, zoledronic acid to lower remodeling without affecting PTH, anti-sclerostin antibody, or anti-sclerostin antibody plus calcium. Non-diseased, untreated littermates served as controls. Vertebral bone morphology (trabecular and cortical) and mechanical properties (structural and material-level) were assessed at 35 weeks of age by microCT and mechanical testing, respectively.

RESULTS

CKD with high PTH resulted in 6-fold higher bone formation rate, significant reductions in the amount of trabecular and cortical bone, and compromised whole bone mechanical properties in the vertebra compared to normal animals. Treatments that reduced bone remodeling were effective in normalizing vertebral structure and mechanical properties only if the treatment reduced serum PTH. Similarly, treatment with anti-sclerostin antibody was effective in enhancing bone mass and mechanical properties but only if combined with PTH-suppressive treatment.

CONCLUSIONS

CKD significantly altered both cortical and trabecular bone properties in the vertebra resulting in compromised mechanical properties and these changes can be normalized by interventions that involve reductions in PTH levels.

Fracture Burden and Risk Factors in Childhood CKD: Results from the CKiD Cohort Study

Childhood chronic kidney disease (CHD) poses multiple threats to bone accrual; however, the associated fracture risk is not well characterized. This prospective cohort study included 537 CKD in Children (CKiD) participants. Fracture histories were obtained at baseline, at years 1, 3, and 5 through November 1, 2009, and annually thereafter. We used Cox regression analysis of first incident fracture to evaluate potential correlates of fracture risk. At enrollment, median age was 11 years, and 16% of patients reported a prior fracture. Over a median of 3.9 years, 43 males and 24 females sustained incident fractures, corresponding to 395 (95% confidence interval [95% CI], 293-533) and 323 (95% CI, 216-481) fractures per 10,000 person-years, respectively. These rates were 2- to 3-fold higher than published general population rates. The only gender difference in fracture risk was a 2.6-fold higher risk in males aged ≥15 years (570/10,000 person-years, adjusted P=0.04). In multivariable analysis, advanced pubertal stage, greater height Z-score, difficulty walking, and higher average log-transformed parathyroid hormone level were independently associated with greater fracture risk (all P≤0.04). Phosphate binder treatment (predominantly calcium-based) was associated with lower fracture risk (hazard ratio, 0.37; 95% CI, 0.15-0.91; P=0.03). Participation in more than one team sport was associated with higher risk (hazard ratio, 4.87; 95% CI, 2.21-10.75; P<0.001). In conclusion, children with CKD have a high burden of fracture. Regarding modifiable factors, higher average parathyroid hormone level was associated with greater risk of fracture, whereas phosphate binder use was protective in this cohort.

How to predict and treat increased fracture risk in chronic kidney disease

Men and women with chronic kidney disease (CKD) are at an increased risk of fracture, and this risk increases as kidney function deteriorates. Fractures are associated with morbidity, mortality and economic costs. Despite this, there is a paucity of data regarding how to evaluate risk for fractures in CKD and how to treat high-risk patients. Evidence suggests that bone mineral density (BMD) as assessed by dual-energy X-ray absorptiometry (DXA) is associated with fractures and can also predict future fractures in predialysis (stages 1-3) patients with CKD. In the absence of considerable abnormalities in markers of mineral metabolism, treatment with antiresorptive agents in men and women with early CKD at high fracture risk may be appropriate. Of note, recent data suggest that low BMD as measured by DXA can also predict fractures in patients with more advanced CKD (stages 4, 5 and 5D). However, treatment in patients with advanced CKD requires bone biopsy, the gold standard to assess bone turnover, prior to treatment. Further research, focusing on noninvasive methods to assess fracture risk and bone turnover, together with randomized controlled trials of treatments to reduce fractures in patients at all stages of CKD, is required.

Factors affecting postoperative activities of daily living in patients with osteoporotic vertebral collapse with neurological deficits

Surgical treatment of osteoporotic vertebral collapse (OVC) with neurological deficits presents significant clinical challenges because some patients have fragile bones and often have medical comorbidities, which affect the severity of osteoporosis. We hypothesized that clinical results of surgery in these patients depend on the extent of medical comorbidities that induce secondary osteoporosis. The aim of this study is to examine the effects of medical history and comorbidities on surgical outcomes for these patients, along with the factors that predict postoperative function in activities of daily living (ADL). We retrospectively reviewed data for 88 patients with OVC and neurological deficits who underwent surgery. We assessed clinical results regarding neurological deficits and function in ADL. The presence or absence of comorbidities responsible for secondary osteoporosis and treatments or medical events that affect bone metabolism were examined. We performed statistical analysis to examine prognostic factors for postoperative function in ADL. Of 88 patients, the distributions of comorbidities, treatment, and events in medical history were as follows: hypertension, 57 patients (64.8%); chronic kidney disease (CKD) stage 3 or 4, 32 (36.4%); diabetes mellitus, 16 (18.2%); liver dysfunction, 11 (12.5%); cardiovascular disease, 10 (11.4%); rheumatoid arthritis, 9 (10.2%); and glucocorticoid intake, 8 (9.1%). Twenty-five patients (28.4%) represented poor postoperative ADL (chair-bound or bed-bound), and 11 of 25 patients with poor postoperative ADL represented full neurological recovery. Multivariate analysis revealed decreased estimated glomerular filtration rate (odds ratio 0.96; 95% confidence interval 0.93-0.99; p = 0.005) and a high serum alkaline phosphatase (ALP) level (odds ratio 1.01; 95% CI 1.00-1.02; p = 0.01) were strong predictive factors for poor postoperative function in ADL. The majority of patients with poor postoperative function in ADL had advanced CKD with a disorder of bone metabolism as well as bone fragility.

Increased hip fracture and mortality in chronic kidney disease individuals: the importance of competing risks

BACKGROUND

Many studies have shown a correlation between chronic kidney disease (CKD) and fracture. However, increased mortality in CKD patients is a competing risk scenario not accounted for in previous studies. Our aim was to investigate the true impact of CKD on hip fracture after accounting for a competing risk with death.

METHODS

We conducted a population-based cohort study to determine the impact of CKD on hip fractures in individuals aged ≥50years old registered in the SIDIAP(Q) database (representative of 1.9 million people in Catalonia, Spain). Cox regression was used to estimate hazard ratio (HR) for death and hip fracture according to CKD status. A competing risk (Fine and Gray) model was fitted to estimate sub-HR for hip fracture in CKD or CKD-free patients accounting for differential mortality.

RESULTS

A total of 873,073 (32,934 (3.8%) CKD) patients were observed for 3 years. During follow-up, 4,823 (14.6%) CKD and 36,328 (4.3%) CKD-free participants died (HR, 1.83 [95% CI, 1.78-1.89]), whilst 522 (1.59%) and 6,292 (0.75%) sustained hip fractures, respectively. Adjusted Cox models showed a significantly increased risk of hip fractures for the CKD group (HR, 1.16 [1.06-1.27]), but this association was attenuated in competing risk models accounting for mortality (SHR, 1.14 [1.03-1.27]).

CONCLUSIONS

Both death and hip fracture rates are increased (by 83% and 16%, respectively) in CKD patients. However, the association between CKD and hip fractures is attenuated when an excess of mortality is taken into account. A competing risk with death must be considered in future analyses of association between CKD and any health outcomes.

Risk factors for fracture among current, persistent users of bisphosphonates

SUMMARY

Bisphosphonate therapy reduces fracture risk but does not eliminate fracture occurrence. We determined the fracture incidence and risk factors for fractures among 14,674 bisphosphonate users in a community setting. Bisphosphonate users remained at risk of fracture, and additional measures to prevent fractures in these patients would be beneficial.

INTRODUCTION

Bisphosphonate therapy reduces but does not eliminate fracture occurrence. The incidence of fracture and risk factors for fractures among persistent, current users of bisphosphonates in a community setting have not been well studied.

METHODS

We conducted a retrospective cohort study of 14,674 bisphosphonate users in a health maintenance organization. Patients were followed until a 3-month gap in therapy, creating a pool of highly compliant [mean medication possession ratio (MPR) of 94%] current users. We used Cox proportional hazards models to identify risk factors for fractures among these persistent, current users.

RESULTS

There were 867 fractures over the period of observation or 3.7 fractures per 100 users per year. Older patients who take multiple medications, have lower bone mineral density, have a history of prior fracture, and suffer from particular comorbidities (i.e., dementia, chronic kidney disease, and rheumatoid arthritis) are at higher risk of fracture while taking bisphosphonates.

CONCLUSION

Persistent, current bisphosphonate users remain at risk of fracture, and additional measures to prevent fractures in these patients would be of benefit.

Increased low-density lipoprotein cholesterol level is associated with non-vertebral fractures in postmenopausal women

Although a high serum low-density lipoprotein cholesterol (LDL-C) level is an established risk factor for atherosclerosis, it is unclear whether it is associated with osteoporosis. In this study, the associations between the serum LDL-C level and bone mineral density (BMD), bone metabolic markers, and the presence of prevalent vertebral or non-vertebral fractures were examined. A total of 211 healthy postmenopausal women (age range, 46-80 years) who visited a community health center were recruited consecutively. Their radiographic and biochemical characteristics were collected. Prevalent vertebral and non-vertebral fractures were found in 49 (23.2%) and 36 (17.1%) subjects, respectively. Simple regression analyses showed that the serum LDL-C level was not significantly correlated with lumbar or femoral BMD or serum levels of total amino-terminal propeptide of type I collagen (PINP) or carboxy-terminal telopeptide of type I collagen (CTX). Logistic regression analyses adjusted for age and BMI showed that the increased serum LDL-C level was selected as an index affecting the presence of prevalent non-vertebral fractures, but not vertebral fractures. This result was still significant after additional adjustments for years since menopause, physical activity, previous cardiovascular events, bone markers, BMD, serum Ca, P, Cr, 25(OH)D, grip strength, tandem gait test, and use of drugs for hyperlipidemia [odds ratio 1.76 (1.13-2.73), p=0.012]. These findings suggest that a high serum LDL-C level may be a risk factor for prevalent non-vertebral fragility fractures independent of bone turnover, bone mass, vitamin D insufficiency, or frail status in postmenopausal women, and that it may be detrimental to bone, as well as blood vessels.

Chronic kidney disease and the skeleton

Fractures across the stages of chronic kidney disease (CKD) could be due to osteoporosis, some form of renal osteodystrophy defined by specific quantitative histomorphometry or chronic kidney disease-mineral and bone disorder (CKD-MBD). CKD-MBD is a systemic disease that links disorders of mineral and bone metabolism due to CKD to either one or all of the following: abnormalities of calcium, phosphorus, parathyroid hormone or vitamin D metabolism; abnormalities in bone turnover, mineralization, volume, linear growth or strength; or vascular or other soft-tissue calcification. Osteoporosis, as defined by the National Institutes of Health, may coexist with renal osteodystrophy or CKD-MBD. Differentiation among these disorders is required to manage correctly the correct disorder to reduce the risk of fractures. While the World Health Organization (WHO) bone mineral density (BMD) criteria for osteoporosis can be used in patients with stages 1-3 CKD, the disorders of bone turnover become so aberrant by stages 4 and 5 CKD that neither the WHO criteria nor the occurrence of a fragility fracture can be used for the diagnosis of osteoporosis. The diagnosis of osteoporosis in stages 4 and 5 CKD is one of the exclusion-excluding either renal osteodystrophy or CKD-MBD as the cause of low BMD or fragility fractures. Differentiations among the disorders of renal osteodystrophy, CKD-MBD or osteoporosis are dependent on the measurement of specific biochemical markers, including serum parathyroid hormone (PTH) and/or quantitative bone histomorphometry. Management of fractures in stages 1-3 CKD does not differ in persons with or without CKD with osteoporosis assuming that there is no evidence for CKD-MBD, clinically suspected by elevated PTH, hyperphosphatemia or fibroblast growth factor 23 due to CKD. Treatment of fractures in persons with osteoporosis and stages 4 and 5 CKD is not evidence-based, with the exception of post-hoc analysis suggesting efficacy and safety of specific osteoporosis therapies (alendronate, risedronate and denosumab) in stage 4 CKD. This review also discusses how to diagnose and manage fragility fractures across the five stages of CKD.