The Skeletal Effects of Inhaled Glucocorticoids

Risk and management of osteoporosis due to inhaled, epidural, intra-articular or topical glucocorticoids

Glucocorticoids (GCs) are widely used by several specialties for the treatment of a variety of diseases and conditions. The unfavorable effect of oral GCs on bone health is well-documented. The ensuing from their use glucocorticoid-induced osteoporosis (GIOP) is the most common cause of medication-induced osteoporosis and fractures. It is uncertain, however, if, and in what extent, GCs administered by other routes affect the skeleton. In the present review, we quote current evidence on the effect of inhaled GCs, epidural and intra-articular steroid injections, and topical GCs on bone outcomes. Although evidence is limited and weak, it seems that a small proportion of the administered GCs may be absorbed, enter the systemic circulation, and adversely affect the skeleton. Potent GCs, higher doses, and longer treatment duration seem to infer the greater risk for bone loss and fractures. There are scarce data, and only for inhaled GCs, regarding the efficacy of antiosteoporotic medications in patients receiving GCs through routes other than oral. Further studies are needed to clarify the relationship between GC administration through these routes and bone outcomes and to help establishing guidelines for the optimal management of such patients.

Treating the Side Effects of Exogenous Glucocorticoids; Can We Separate the Good From the Bad?

It is estimated that 2% to 3% of the population are currently prescribed systemic or topical glucocorticoid treatment. The potent anti-inflammatory action of glucocorticoids to deliver therapeutic benefit is not in doubt. However, the side effects associated with their use, including central weight gain, hypertension, insulin resistance, type 2 diabetes (T2D), and osteoporosis, often collectively termed iatrogenic Cushing's syndrome, are associated with a significant health and economic burden. The precise cellular mechanisms underpinning the differential action of glucocorticoids to drive the desirable and undesirable effects are still not completely understood. Faced with the unmet clinical need to limit glucocorticoid-induced adverse effects alongside ensuring the preservation of anti-inflammatory actions, several strategies have been pursued. The coprescription of existing licensed drugs to treat incident adverse effects can be effective, but data examining the prevention of adverse effects are limited. Novel selective glucocorticoid receptor agonists and selective glucocorticoid receptor modulators have been designed that aim to specifically and selectively activate anti-inflammatory responses based upon their interaction with the glucocorticoid receptor. Several of these compounds are currently in clinical trials to evaluate their efficacy. More recently, strategies exploiting tissue-specific glucocorticoid metabolism through the isoforms of 11β-hydroxysteroid dehydrogenase has shown early potential, although data from clinical trials are limited. The aim of any treatment is to maximize benefit while minimizing risk, and within this review we define the adverse effect profile associated with glucocorticoid use and evaluate current and developing strategies that aim to limit side effects but preserve desirable therapeutic efficacy.

Inhaled corticosteroids and risk of osteoporosis in late-middle-aged subjects: a multicenter European cohort study

BACKGROUND

Inhaled corticosteroids have been widely used for the regular treatment of asthma and chronic obstructive pulmonary diseases (COPD) over the past few decades. To date, studies investigating the effects of inhaled corticosteroids (ICS) on bone in populations including asthma and COPD patients, show conflicting results. The skeletal effects of ICS remain poorly understood. We assessed the association between ICS exposure and self-reported osteoporosis diagnosis in a European cohort study.

METHODS

The analysis was carried out by using clinical and questionnaire data available for subjects participating in the ECRHS III (European Community Respiratory Health Survey) with age >55 years.

RESULTS

Among the 3004 enrolled subjects, 245 were ICS users with an exposure ≥12 months. Osteoporosis was reported by 16 subjects in the ICS group (6.5%) and by 167 in the not exposed group (6.1%). The adjusted risk of osteoporosis in ICS users (≥12 months) was not greater in exposed subjects when compared with the unexposed ones (OR=1.02, 95CI%: 0.51, 2.03). The same result was observed even when considering in the analysis a longer exposure to the ICS use (≥36.5 months, the median ICS exposure for all subjects). History of COPD, use of oral corticosteroids, Body Mass Index, smoking and physical activity did not show any evidence of an association with osteoporosis.

CONCLUSIONS

Our study did not show any significant association between long- term ICS use and self-reported diagnosis of osteoporosis in subjects aged >55 years. To explore the real effect of ICS on bone status, further studies are needed, especially in the long-term ICS exposure.

Clinical assessment of balance and functional impairments in people with stable chronic obstructive pulmonary disease: a systematic review and meta-analysis

The objective of this study was to compare the balance and functional capacity between stable chronic obstructive pulmonary disease (COPD) patients versus healthy controls using clinical tests. A comprehensive search of PubMed/MEDLINE, the Cochrane Central Register of Controlled Trials (CENTRAL), Embase and Web of Science was conducted from inception to 21 January 2022. Studies reporting the association between COPD status and balance or functional capacity using clinical tests were included. Two independent reviewers examined the titles and abstracts, extracted the data using a standardised form, and assessed the risk of bias of the included articles. A total of 27 studies with 2420 individuals with stable COPD were included. Overall, the risk of bias in the included studies was low to moderate. The meta-analysis showed a higher history of falls in individuals with COPD (odds ratio 1.59, 95% CI 1.25-2.02). Furthermore, an overall effect in favour of the healthy controls was observed in the Timed Up and Go (mean difference: 2.61 s, 95% CI 1.79-3.43), Berg Balance Scale (mean difference: -6.57 points, 95% CI -8.31 to -4.83), static balance tests (standardised mean difference: -1.36, 95% CI -2.10 to -0.62) and the 6-min walk test (mean difference: -148.21 m, 95% CI -219.37 to -77.39). In conclusion, individuals with stable COPD have worse balance and functional capacity compared to healthy controls. These results may guide clinicians to elaborate on therapeutic strategies focused on screening of balance and functional impairments. This is in addition to generating rehabilitation guidelines aimed at reducing the risk of falling in people with COPD.

Clinical Effects of Rehabilitation on Balance in People With Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

Background

Patients with chronic obstructive pulmonary disease (COPD) have systemic damage secondary to the primary pulmonary impairment, expressed in impaired peripheral musculature and a deficit in postural control compared to healthy subjects. This study aimed to determine the effects of rehabilitation on balance in patients with COPD.

Methods

An exhaustive search was conducted in four databases (Pubmed, Cochrane Library, EMBASE, Web of Science). Articles with a population of COPD receiving rehabilitation (therapeutic exercise, pulmonary rehabilitation, or physical therapy modalities) in an outpatient setting were included. Two independent reviewers selected and assessed the study quality. The risk of bias was assessed with the Cochrane Risk of Bias Tool for Randomized Controlled Trials.

Results

A total of eight studies involving 284 patients were included in the qualitative synthesis. The meta-analysis showed an overall result in favor of balance training for the Berg Balance Scale (mean difference 3.91 points; 95% CI: 1.51 to 6.31; P = 0.001), Timed Up and Go test (mean difference −1.58 s; 95% CI: −2.63 to −0.53; P = 0.003) and Unipedal stance test (mean difference 3.56 s, 95% CI: 2.58 to 4.54; P).

Conclusion

This meta-analysis revealed that rehabilitation improve static and dynamic balance in patients with COPD.

Systematic Review Registration

PROSPERO ID: CRD42020218367.

Secondary Osteoporosis and Metabolic Bone Diseases

Fragility fracture is a worldwide problem and a main cause of disability and impaired quality of life. It is primarily caused by osteoporosis, characterized by impaired bone quantity and or quality. Proper diagnosis of osteoporosis is essential for prevention of fragility fractures. Osteoporosis can be primary in postmenopausal women because of estrogen deficiency. Secondary forms of osteoporosis are not uncommon in both men and women. Most systemic illnesses and organ dysfunction can lead to osteoporosis. The kidney plays a crucial role in maintaining physiological bone homeostasis by controlling minerals, electrolytes, acid-base, vitamin D and parathyroid function. Chronic kidney disease with its uremic milieu disturbs this balance, leading to renal osteodystrophy. Diabetes mellitus represents the most common secondary cause of osteoporosis. Thyroid and parathyroid disorders can dysregulate the osteoblast/osteoclast functions. Gastrointestinal disorders, malnutrition and malabsorption can result in mineral and vitamin D deficiencies and bone loss. Patients with chronic liver disease have a higher risk of fracture due to hepatic osteodystrophy. Proinflammatory cytokines in infectious, autoimmune, and hematological disorders can stimulate osteoclastogenesis, leading to osteoporosis. Moreover, drug-induced osteoporosis is not uncommon. In this review, we focus on causes, pathogenesis, and management of secondary osteoporosis.

Abnormal Bone Tissue Organization and Osteocyte Lacunocanalicular Network in Early-Onset Osteoporosis Due to SGMS2 Mutations

Pathological variants in SGMS2, encoding sphingomyelin synthase 2 (SMS2), result in a rare autosomal dominant skeletal disorder with cranial doughnut lesions. The disease manifests as early-onset osteoporosis or a more severe skeletal dysplasia with low bone mineral density, frequent fractures, long-bone deformities, and multiple sclerotic cranial lesions. The exact underlying molecular features and skeletal consequences, however, remain elusive. This study investigated bone tissue characteristics in two adult males with a heterozygous SGMS2 mutation p.Arg50* and significant bone fragility. Transiliac bone biopsy samples from both (patient 1: 61 years; patient 2: 29 years) were analyzed by bone histomorphometry, confocal laser scanning microscopy, and quantitative backscattered electron imaging (qBEI). Bone histomorphometry portrayed largely normal values for structural and turnover parameters, but in both patient 1 and patient 2, respectively, osteoid thickness (-1.80 SD, -1.37 SD) and mineralizing surface (-1.03 SD, -2.73 SD) were reduced and osteoid surface increased (+9.03 SD, +0.98 SD), leading to elevated mineralization lag time (+8.16 SD, +4.10 SD). qBEI showed low and heterogeneous matrix mineralization (CaPeak -2.41 SD, -3.72 SD; CaWidth +7.47 SD, +4.41 SD) with a chaotic arrangement of collagenous fibrils under polarized light. Last, osteocyte lacunae appeared abnormally large and round in shape and the canalicular network severely disturbed with short-spanned canaliculi lacking any orderliness or continuity. Taken together, these data underline a central role for functional SMS2 in bone matrix organization and mineralization, lacunocanalicular network, and in maintaining skeletal strength and integrity. These data bring new knowledge on changes in bone histology resulting from abnormal sphingomyelin metabolism and aid en route to better understanding of sphingolipid-related skeletal disorders. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Mechanical loading alleviated the inhibition of β2-adrenergic receptor agonist terbutaline on bone regeneration

The long-term use of adrenergic medication in treating various conditions, such as asthma, increases the chances of bone fracture. Dynamic mechanical loading at a specific time is a method for improving bone quality and promoting healing. Therefore, we hypothesized that precisely controlling the mechanical environment can contribute to the alleviation of the negative effects of chronic treatment with the common asthma drug terbutaline, which is a β2-adrenergic receptor agonist that facilitates bone homeostasis and defect repair through its anabolic effect on osteogenic cells. Our in vitro results showed that terbutaline can directly inhibit osteogenesis by impairing osteogenic differentiation and mineralization. Chronic treatment in vivo was simulated by administering terbutaline to C57BL/6J mice for 4 weeks before bone defect surgery and mechanical loading. We utilized a stabilized tibial defect model, which allowed the application of anabolic mechanical loading. During homeostasis, chronic terbutaline treatment reduced the bone formation rate, the fracture toughness of long bones, and the concentrations of bone formation markers in the sera. During defect repair, terbutaline decreased the bone volume, type H vessel, and total blood vessel volume. Terbutaline treatment reduced the number of osteogenic cells. Periostin, which was secreted mainly by Prrx1+ osteoprogenitors and F4/80+ macrophages, was inhibited by treating the bone defect with terbutaline. Interestingly, controlled mechanical loading facilitated the recovery of bone volume and periostin expression and the number of osteogenic cells within the defect. In conclusion, mechanical loading can rescue negative effects on new bone accrual and repair induced by chronic terbutaline treatment.

The skeletal consequences of epidural steroid injections: a literature review

This literature review summarized studies that evaluated the effects of epidural steroid injections (ESIs) on skeletal health. While evidence is limited, studies suggest that ESIs may cause bone loss. Better understanding of these skeletal consequences will help foster strategies to prevent bone loss in the growing population of patients receiving ESIs.

PURPOSE

Approximately nine million epidural steroid injections (ESIs) are administered annually in the United States to treat radicular back pain. ESIs often provide pain relief and functional improvement. While the overall incidence of adverse events resulting from ESIs is low, their effects on the skeleton are poorly understood. This is an important consideration given the profound skeletal impact of other forms of glucocorticoids.

METHODS

Ovid MEDLINE and PubMed search results since 2010, including older, frequently referenced publications were reviewed.

RESULTS

Systemic absorption of glucocorticoids occurs after ESI, which can cause hyperglycemia and endogenous cortisol suppression. The majority of studies investigating the skeletal effects of ESIs are retrospective. Several have found a relationship between low areal bone mineral density (BMD) by dual-energy x-ray absorptiometry and ESI exposure, but this finding is not uniform. Recently a dose-response relationship between ESI exposure and low spine volumetric BMD by computed tomography has been reported. Few studies have investigated the relationship between ESI exposure and fracture risk. Results of these studies are conflicting, and most have not been adequately powered to detect fracture outcomes.

CONCLUSIONS

While evidence is limited, studies suggest that ESIs may cause bone loss, particularly those investigating volumetric BMD. Larger doses appear to confer greater risk. Further prospective studies are needed to investigate the relationship between ESI and fracture risk. Better understanding of the skeletal consequences of ESIs will help foster strategies to prevent bone loss in the growing population of patients receiving this treatment.

[Osteoporosis in pneumological diseases : Joint guideline of the Austrian Society for Bone and Mineral Research (ÖGKM) and the Austrian Society for Pneumology (ÖGP)]

Chronic inflammation induces proinflammatory cytokine cascades. In addition to systemic inflammation, hypoxemia, hypercapnia, a catabolic metabolism, gonadal or thyroid dysfunction, musculoskeletal dysfunction and inactivity as well as vitamin D deficiency contribute to an increased risk of fragility fractures. Iatrogenic causes of osteoporosis are long-term use of inhaled or systemic glucocorticoids (GC). Inhalative GC application in asthma is often indicated in childhood and adolescence, but interstitial lung diseases such as chronic organizing pneumonia, COPD, sarcoid or rheumatic diseases with lung involvement are also treated with inhalative or oral GC. In patients with cystic fibrosis, malabsorption in the context of pancreatic insufficiency, hypogonadism and chronic inflammation with increased bone resorption lead to a decrease in bone structure. After lung transplantation, immunosuppression with GC is a risk factor.The underlying pneumological diseases lead to a change in the trabecular and cortical bone microarchitecture and to a reduction in osteological formation and resorption markers. Hypercapnia, acidosis and vitamin D deficiency can accelerate this process and thus increase the individual risk of osteoporotic fragility fractures.A bone mineral density measurement with a T‑Score < -2.5 is a threshold value for the diagnosis of osteoporosis; in contrast the vast majority of all osteoporotic fractures occur with a T‑Score > -2.5. A history of low-trauma fracture indicates osteological therapy.All antiresorptive or anabolic drugs approved in Austria for the treatment of osteoporosis are also indicated for pneumological patients with an increased fragility fracture risk of bone fractures in accordance with the national reimbursement criteria.

Practical Guidance for Prevention and Management of Glucocorticoid-Induced Osteoporosis for the Allergist/Immunologist

Osteoporosis is a silent disorder with dire consequences, and glucocorticoid use remains the most common iatrogenic cause illustrated by the fact that 30% to 50% of subjects on such long-term therapy experience fractures (Oimomi M, Nakamichi T, Ohara T, Sakai M, Igaki N, Hata F, et al. Fructose-related glycation. Diabetes Res Clin Pract 1989;7:137-9; Reid IR. Glucocorticoid osteoporosis--mechanisms and management. Eur J Endocrinol 1997;137:209-17). By directly affecting bone quality while actively used, glucocorticoids increase the risk of fracture that is independent of a subject's bone density status at the time (Weinstein RS. True strength. J Bone Miner Res 2000;15:621-5). A large number of subjects seen in an allergy and immunology clinic have asthma, chronic rhinosinusitis, or other chronic inflammatory diseases, necessitating the use of these medications and placing them at higher risk for this disease. Data on the effects of both oral and inhaled glucocorticoids on fracture risk are presented. This review concretizes the importance of osteoporosis, its pathophysiology, and provides practical guidelines to prevent and treat it. Management recommendations are tailored to 2 different age groups. The first group consists of children, adolescents, and adults 40 years or younger with a focus on attaining peak bone mass. The second group consists of adults 40 years or older where the use of imaging modalities and Fracture Risk Assessment Tool scores helps triage subjects into fracture risk categories. Those at moderate to high risk require bone-sparing medications. Universal preventive measures for both groups are reviewed. Complicated and severe cases may need additional expertise by an endocrinologist or rheumatologist.

Effects of Systemic Glucocorticoid Use on Fracture Risk: A Population-Based Study

BACKGROUND

Long-term glucocorticoid use increases fracture risk by reducing bone mass. This study evaluated the relationship between hip and vertebral fractures and the total amount of systematic glucocorticoid use.

METHODS

We randomly selected 1,896,159 people aged 20 to 100 years who participated in the National Health Checkup program in 2006. The amount of glucocorticoids prescribed was calculated based on the defined daily dose (DDD). The total DDD was obtained by adding oral and parenteral glucocorticoids for 6 months from the index date. Subjects were categorized into four groups according to total glucocorticoid DDDs: non-users (DDDs=0), low users (0&lt; DDDs ≤45), intermediate users (45&lt; DDDs ≤90), and high users (90&lt; DDDs). We followed them for 2 years. A multivariate Cox proportional hazard model was used to evaluate the effects of the total amount of glucocorticoid use on hip and vertebral fractures.

RESULTS

Higher glucocorticoid use was associated with a higher risk of vertebral fracture. Relative to non-users, the vertebral fracture risk was 1.39 times higher in the low-user group, 1.94 times higher in the intermediate-user group, and 2.43 times higher in the highuser group. The risk of hip fracture was 1.72 times higher in intermediate users and 3.28 times higher in high users than in non-users.

CONCLUSION

As the amount of glucocorticoid use for 6 months increased, the risk of hip and vertebral fractures became higher. In order to prevent fractures, it is necessary for doctors to evaluate the total amount of glucocorticoid prescribed to the patient and to provide appropriate treatment.

Updates in epidemiology, pathophysiology and management strategies of glucocorticoid-induced osteoporosis

INTRODUCTION

Endogenous or exogenous (corticosteroid-induced) glucocorticoids (GCs) excess represents, together with diabetes, the most common cause of secondary osteoporosis.

AREAS COVERED

We present a comprehensive overview about the pathophysiology, clinical management and treatment of GCs induced osteoporosis (GIOP). According to PRISMA guidelines, a literature search identifying articles about bone and GCs was done.

EXPERT OPINION

Despite the progress over the years and the increase in therapeutic options, there still are controversial issues about the management of GIOP. These mainly include the failure of BMD or FRAX to completely account for the rapid increase in fracture risk of most GC-treated patients, the understanding about the independent contribution on bone fragility of the underlying disease requiring GCs therapy, and the necessity of clearer information about the anti-fracture efficacy and long term-safety of most therapeutic options. Moreover, there are no specific indications for the management of bone fragility in endogenous hypercortisolism. Notwithstanding the above limitations there is a general consensus to recommend an assessment of fracture risk in all individuals >40 years committed to receive (or continuing) high dose (>7.5 mg of prednisone equivalent) GCs for ≥3 months and in all patients with fragility fracture history.

Intestinal Ca2+ absorption revisited: A molecular and clinical approach

Ca2+ has an important role in the maintenance of the skeleton and is involved in the main physiological processes. Its homeostasis is controlled by the intestine, kidney, bone and parathyroid glands. The intestinal Ca2+ absorption occurs mainly via the paracellular and the transcellular pathways. The proteins involved in both ways are regulated by calcitriol and other hormones as well as dietary factors. Fibroblast growth factor 23 (FGF-23) is a strong antagonist of vitamin D action. Part of the intestinal Ca2+ movement seems to be vitamin D independent. Intestinal Ca2+ absorption changes according to different physiological conditions. It is promoted under high Ca2+ demands such as growth, pregnancy, lactation, dietary Ca2+ deficiency and high physical activity. In contrast, the intestinal Ca2+ transport decreases with aging. Oxidative stress inhibits the intestinal Ca2+ absorption whereas the antioxidants counteract the effects of prooxidants leading to the normalization of this physiological process. Several pathologies such as celiac disease, inflammatory bowel diseases, Turner syndrome and others occur with inhibition of intestinal Ca2+ absorption, some hypercalciurias show Ca2+ hyperabsorption, most of these alterations are related to the vitamin D endocrine system. Further research work should be accomplished in order not only to know more molecular details but also to detect possible therapeutic targets to ameliorate or avoid the consequences of altered intestinal Ca2+ absorption.

Biomarkers in WNT1 and PLS3 Osteoporosis: Altered Concentrations of DKK1 and FGF23

Recent advancements in genetic research have uncovered new forms of monogenic osteoporosis, expanding our understanding of the molecular pathways regulating bone health. Despite active research, knowledge on the pathomechanisms, disease-specific biomarkers, and optimal treatment in these disorders is still limited. Mutations in WNT1, encoding a WNT/β-catenin pathway ligand WNT1, and PLS3, encoding X chromosomally inherited plastin 3 (PLS3), both result in early-onset osteoporosis with prevalent fractures and disrupted bone metabolism. However, despite marked skeletal pathology, conventional bone markers are usually normal in both diseases. Our study aimed to identify novel bone markers in PLS3 and WNT1 osteoporosis that could offer diagnostic potential and shed light on the mechanisms behind these skeletal pathologies. We measured several parameters of bone metabolism, including serum dickkopf-1 (DKK1), sclerostin, and intact and C-terminal fibroblast growth factor 23 (FGF23) concentrations in 17 WNT1 and 14 PLS3 mutation-positive subjects. Findings were compared with 34 healthy mutation-negative subjects from the same families. Results confirmed normal concentrations of conventional metabolic bone markers in both groups. DKK1 concentrations were significantly elevated in PLS3 mutation-positive subjects compared with WNT1 mutation-positive subjects (p < .001) or the mutation-negative subjects (p = .002). Similar differences were not seen in WNT1 subjects. Sclerostin concentrations did not differ between any groups. Both intact and C-terminal FGF23 were significantly elevated in WNT1 mutation-positive subjects (p = .039 and p = .027, respectively) and normal in PLS3 subjects. Our results indicate a link between PLS3 and DKK1 and WNT1 and FGF23 in bone metabolism. The normal sclerostin and DKK1 levels in patients with impaired WNT signaling suggest another parallel regulatory mechanism. These findings provide novel information on the molecular networks in bone. Extended studies are needed to investigate whether these biomarkers offer diagnostic value or potential as treatment targets in osteoporosis. © 2020 American Society for Bone and Mineral Research.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

Long-term use of inhaled glucocorticoids in patients with stable chronic obstructive pulmonary disease and risk of bone fractures: a narrative review of the literature

Patients with chronic obstructive pulmonary disease (COPD) demonstrate a greater osteoporosis prevalence than the general population. This osteoporosis risk may be enhanced by treatment with inhaled corticosteroids (ICSs), which are recommended for COPD management when combined with long-acting bronchodilators, but may also be associated with reduced bone mineral density (BMD). We conducted a narrative literature review reporting results of randomized controlled trials (RCTs) of an ICS versus placebo over a treatment period of at least 12 months, with the aim of providing further insight into the link between bone fractures and ICS therapy. As of 16 October 2017, we identified 17 RCTs for inclusion. The ICSs studied were budesonide (six studies), fluticasone propionate (five studies), mometasone furoate (three studies), beclomethasone dipropionate, triamcinolone acetonide, and fluticasone furoate (one each). We found no difference in the number of bone fractures among patients receiving ICSs versus placebo across the six identified RCTs reporting fracture data. BMD data were available for subsets of patients in few studies, and baseline BMD data were rare; where these data were given, they were reported for treatment groups without stratification for factors known to affect BMD. Risk factors for reduced BMD and fractures, such as smoking and physical activity, were also often not reported. Furthermore, a standardized definition of the term "fracture" was not employed across these studies. The exact relationship between long-term ICS use and bone fracture incidence in patients with stable COPD remains unclear in light of our review. We have, however, identified several limiting factors in existing studies that may form the basis of future RCTs designed specifically to explore this relationship.

Mast cells in mastocytosis and allergy - Important player in metabolic and immunological homeostasis

The role of mast cell (MC) activity in pathophysiology is complex and challenging and its clinical effects are difficult to predict. Apart from the known role of MCs in basic immunological processes and allergy, underlined is their importance in bone mineralization and in regulation of autoimmune reactions. Mast cell mediators, especially those released from mast cells in degranulation, but also those released constitutively, are important both in metabolic and immunological processes. Mastocytosis is a heterogeneous group of disorders characterized by accumulation of MC in one or more organs. There are scientific data indicating that mastocytosis patients are at increased risk of osteoporosis in the systemic form of the disease and children with cutaneous mastocytosis have a higher rate of hypogammaglobulinemia. Moreover, the origin of osteoporosis in patients with allergy is no longer considered as linked to steroid therapy only, but to the mast cell mediators' activity as well. There are indications that osteoporosis symptoms in this group of patients may develop independently of the cumulative steroids' dose. Thus, the influence of mast cells on metabolic and immunologic processes in allergic patients should be investigated. The assessment of mast cell activity and burden in mastocytosis may be used to guide clinical management of patients with allergy.

Glucocorticoid-Induced Osteoporosis: Management Challenges in Older Patients

Glucocorticoid-induced osteoporosis remains the most common type of secondary osteoporosis, mostly due to use of oral glucocorticoids rather than due to endogenous overproduction of cortisol. Partly because glucocorticoids are prescribed by a wide variety of clinicians for many different inflammatory disorders, only a minority of older individuals have adequate and timely assessment of their enhanced fracture risk, and fewer are offered treatment. Assessment should include bone density, the FRAX calculation, and, in many cases, images of the spine. Glucocorticoids decrease osteoblast function and increase apoptosis of osteoblasts and osteocytes, leading to increased fracture risk soon after starting glucocorticoids. Guidelines provide evidence-based recommendations for evaluation and treatment, but there are differences in extant guidelines, and methods to improve adherence to the guidelines have mostly failed. A strong case can be made to use anabolic drugs first in high-risk patients based on pathophysiology and head-to-head clinical trials.

Abnormal microarchitecture and stiffness in postmenopausal women using chronic inhaled glucocorticoids

Postmenopausal (PM) women using inhaled glucocorticoids (IGCs) had substantial abnormalities in volumetric BMD (vBMD), microarchitecture, and stiffness using high resolution peripheral computed tomography (HRpQCT) compared to age- and race-matched controls. Abnormalities were most severe at the radius. These preliminary results suggest that there may be major, heretofore unrecognized, skeletal deficits in PM women using IGCs.

INTRODUCTION

While oral glucocorticoids are well recognized to have destructive skeletal effects, less is known about the effects of IGCs. The detrimental skeletal effects of IGCs may be greatest in PM women, in whom they compound negative effects of estrogen loss and aging. The goal of this study was to evaluate microarchitecture and stiffness in PM women using chronic IGCs.

METHODS

This case-control study compared PM women using IGCs for ≥ 6 months (n = 20) and controls matched for age and race/ethnicity (n = 60). Skeletal parameters assessed included areal BMD (aBMD) by DXA, trabecular and cortical vBMD and microarchitecture by HRpQCT of the radius and tibia, and whole bone stiffness by finite element analysis.

RESULTS

By DXA, mean values in both groups were in the osteopenic range; hip aBMD was lower in IGC users (P < 0.04). By HRpQCT, IGC users had lower total, cortical, and trabecular vBMD at both radius and tibia (all P < 0.05). IGC users had lower cortical thickness, lower trabecular number, greater trabecular separation and heterogeneity at the radius (all P < 0.03), and greater heterogeneity at the tibia (P < 0.04). Whole bone stiffness was lower in IGC users at radius (P < 0.03) and tended to be lower at the tibia (P = 0.09).

CONCLUSIONS

PM women using IGCs had substantial abnormalities in vBMD, microarchitecture, and stiffness compared to controls. These abnormalities were most severe at the radius. These preliminary results suggest that there may be major, heretofore unrecognized, skeletal deficits in PM women using IGCs.

Design of a Clinical Decision Support System for Fracture Prediction Using Imbalanced Dataset

More than 1 billion people suffer from chronic respiratory diseases worldwide, accounting for more than 4 million deaths annually. Inhaled corticosteroid is a popular medication for treating chronic respiratory diseases. Its side effects include decreased bone mineral density and osteoporosis. The aims of this study are to investigate the association of inhaled corticosteroids and fracture and to design a clinical support system for fracture prediction. The data of patients aged 20 years and older, who had visited healthcare centers and been prescribed with inhaled corticosteroids within 2002-2010, were retrieved from the National Health Insurance Research Database (NHIRD). After excluding patients diagnosed with hip fracture or vertebrate fractures before using inhaled corticosteroid, a total of 11645 patients receiving inhaled corticosteroid therapy were included for this study. Among them, 1134 (9.7%) were diagnosed with hip fracture or vertebrate fracture. The statistical results showed that demographic information, chronic respiratory diseases and comorbidities, and corticosteroid-related variables (cumulative dose, mean exposed daily dose, follow-up duration, and exposed duration) were significantly different between fracture and nonfracture patients. The clinical decision support systems (CDSSs) were designed with integrated genetic algorithm (GA) and support vector machine (SVM) by training and validating the models with balanced training sets obtained by random and cluster-based undersampling methods and testing with the imbalanced NHIRD dataset. Two different objective functions were adopted for obtaining optimal models with best predictive performance. The predictive performance of the CDSSs exhibits a sensitivity of 69.84-77.00% and an AUC of 0.7495-0.7590. It was concluded that long-term use of inhaled corticosteroids may induce osteoporosis and exhibit higher incidence of hip or vertebrate fractures. The accumulated dose of ICS and OCS therapies should be continuously monitored, especially for patients with older age and women after menopause, to prevent from exceeding the maximum dosage.

Metabolic Disorders in Chronic Lung Diseases

Chronic lung diseases represent complex diseases with gradually increasing incidence, characterized by significant medical and financial burden for both patients and relatives. Their increasing incidence and complexity render a comprehensive, multidisciplinary, and personalized approach critically important. This approach includes the assessment of comorbid conditions including metabolic dysfunctions. Several lines of evidence show that metabolic comorbidities, including diabetes mellitus, dyslipidemia, osteoporosis, vitamin D deficiency, and thyroid dysfunction have a significant impact on symptoms, quality of life, management, economic burden, and disease mortality. Most recently, novel pathogenetic pathways and potential therapeutic targets have been identified through large-scale studies of metabolites, called metabolomics. This review article aims to summarize the current state of knowledge on the prevalence of metabolic comorbidities in chronic lung diseases, highlight their impact on disease clinical course, delineate mechanistic links, and report future perspectives on the role of metabolites as disease modifiers and therapeutic targets.

Long-term Use of Inhaled Corticosteroids in COPD and the Risk of Fracture

BACKGROUND

It is uncertain whether long-term use of inhaled corticosteroids (ICSs), widely used to treat COPD, increases the risk of fracture, particularly in women, in view of the postmenopausal risks. We assessed whether long-term ICS use in patients with COPD increases the risk of hip or upper extremity fractures, and examined sex-related differences.

METHODS

The Quebec health-care databases were used to form a cohort of patients with COPD over 1990 to 2005, followed until 2007 for the first hip or upper extremity fracture. In a nested case-control analysis, each case of fracture was matched with 20 control subjects on age, sex, and follow-up time. The adjusted rate ratio (RR) of fracture with ICS use, by duration and dose, was estimated using conditional logistic regression, with an interaction term to compare the risk in men and women.

RESULTS

In the cohort of 240,110 subjects, 19,396 sustained a fracture during a mean 5.3 years (rate, 15.2 per 1,000 per year). Any use of ICSs was not associated with an increased rate of fracture (RR, 1.00; 95% CI, 0.97-1.03). The fracture rate was increased with > 4 years of ICS use at daily doses ≥ 1,000 μg in fluticasone equivalents (RR, 1.10; 95% CI, 1.02-1.19). This risk increase did not differ between men and women.

CONCLUSIONS

Long-term ICS use at high doses is associated with a modest increase in the risk of hip and upper extremity fractures in patients with COPD. This dose-duration risk increase does not appear to be higher for women.