Prevention and treatment strategies for glucocorticoid-induced osteoporotic fractures

Glucocorticoids are the most common cause of drug-related osteoporosis. We reviewed current evidence on risk factors for glucocorticoid-induced osteoporosis (GIOP) and prevention and treatment of GIOP-related fractures. Guidelines for GIOP management published since 2000 were also reviewed. Significant bone loss and increased fracture risk is seen with daily prednisone doses as low as 5 mg. Alternate-day glucocorticoid therapy can lead to similar bone loss. No conclusive evidence exists for a safe minimum dose or duration of glucocorticoid exposure. Physicians should consider risk factors for involutional osteoporosis such as older age, postmenopausal status, and baseline bone density measurements as they assess patients for prevention or treatment of GIOP. Bisphosphonates were reported to reduce GIOP-related vertebral fractures, but inconclusive data exist for hip fractures associated with glucocorticoid use. Hormone replacement therapy and parathyroid hormone analogs are effective in preserving bone density in GIOP. The risk of osteoporosis and fractures should be routinely assessed in patients receiving glucocorticoid therapy. Effective prevention and treatment options are available and can result in meaningful reduction of GIOP-related morbidity and mortality. Current guidelines for GIOP management recommend bisphosphonates, especially alendronate and risedronate, as first-line agents for GIOP, and these guidelines propose the preventive use of bisphosphonates early in the course of glucocorticoid therapy in high-risk patient subgroups.     

Basics and management of glucocorticoid-induced osteoporosis

Glucocorticoids interfere with bone metabolism at different levels. Therefore, glucocorticoid-induced osteoporosis (GIO) is the most frequent form of secondary osteoporosis and up to 50 percent of patients on chronic glucocorticoid therapy suffer fractures. This is also because GIO is still under-diagnosed and not adequately treated. Besides, the fracture risk is higher in GIO than in primary osteoporosis even in the presence of equal bone mass density. The risk of osteoporotic fractures increases with dose and duration of glucocorticoid therapy, although the loss of bone mass is more prominent within the first three to twelve months after initiation of treatment. Besides glucocorticoid treatment, other factors, such as e.g. the underlying disease, substantially influence the fracture risk. Therefore, a diagnostic screening is mandatory in each case and should include the patient's history, physical examination, laboratory studies, evaluation of the bone-mass density by dual X-ray absorptiometry and imaging of the spine. Education of the patients and pharmacological prevention are very important, antiresorptive therapy has to be started earlier than in primary osteoporosis and osteoanabolic agents have also been proven to be effective.     

Grundlagen und Management der glukokortikoidinduzierten Osteoporose

Glucocorticoids interfere with bone metabolism at different levels. Therefore, glucocorticoid-induced osteoporosis (GIO) is the most frequent form of secondary osteoporosis and up to 50 percent of patients on chronic glucocorticoid therapy suffer fractures. This is also because GIO is still under-diagnosed and not adequately treated. Besides, the fracture risk is higher in GIO than in primary osteoporosis even in the presence of equal bone mass density. The risk of osteoporotic fractures increases with dose and duration of glucocorticoid therapy, although the loss of bone mass is more prominent within the first three to twelve months after initiation of treatment. Besides glucocorticoid treatment, other factors, such as e.g. the underlying disease, substantially influence the fracture risk. Therefore, a diagnostic screening is mandatory in each case and should include the patient’s history, physical examination, laboratory studies, evaluation of the bone-mass density by dual X-ray absorptiometry and imaging of the spine. Education of the patients and pharmacological prevention are very important, antiresorptive therapy has to be started earlier than in primary osteoporosis and osteoanabolic agents have also been proven to be effective.     

Declining bone mass in men with chronic pulmonary disease: contribution of glucocorticoid treatment, body mass index, and gonadal function

BACKGROUND: Men with chronic lung disease (CLD) are at risk for osteoporosis, but the relative contributions of their chronic pulmonary disease, glucocorticoid therapy, and other factors toward loss of bone has not been established. Understanding the relative importance of these factors would assist in selecting patients for bone densitometry screening and in policy decisions regarding Medicare reimbursement. OBJECTIVE: To identify patients with CLD who are most likely to benefit from bone densitometry screening based on clinical and biochemical measures. DESIGN: Cross-sectional medical survey. PATIENTS: Patients with CLD who were treated with either oral, inhaled, or no glucocorticoid therapy. A control group without lung disease was recruited from the same clinic population. MEASUREMENTS: Dual-energy X-ray absorptiometry was obtained for each group, and the association between bone mass and clinical variables, glucocorticoid use, gonadal hormones, and biochemical markers of bone metabolism was determined. RESULTS: Osteoporosis (a T score < -2.5 at the hip or spine) was five times as likely in patients with CLD as in control subjects. Although the prevalence of osteoporosis was higher (ninefold) after chronic glucocorticoid therapy, patients with CLD who had never been treated with glucocorticoids had a substantial (fourfold) risk of osteoporosis. Chronic inhaled glucocorticoid therapy offered no protection from bone loss compared to treatment with oral glucocorticoids. Of the clinical and biochemical measures that were obtained, bone mass was weakly correlated with body mass index (BMI), serum estradiol-17beta, and N-telopeptide, but not with testosterone, alkaline phosphatase, bone-specific alkaline phosphatase, or osteocalcin. CONCLUSION: Patients with CLD should be considered for bone densitometry screening regardless of glucocorticoid use. Those patients with a low BMI and/or decreased serum estradiol-17beta comprise a subgroup with increased risk for osteoporosis.     

Osteopenia

Under the current diagnostic criteria for primary osteoporosis, patients are diagnosed as having osteopenia if their bone density is between 70 and 80% of the average bone density of young adult women. Osteopenia is essentially a precursor for osteoporosis, and because prevention is the basis of osteoporosis treatment, halting the progression of osteopenia into osteoporosis is very important. In other words, the risk factors associated with osteoporosis in each patient must be assessed, and if rapid bone mass loss is expected or confirmed, drug therapy should then be actively administered.     

An update on glucocorticoid-induced osteoporosis

In general, bone loss from glucocorticoid treatment occurs rapidly within the first 6 months of therapy. Glucocorticoids alter bone metabolism by multiple pathways; however, the bone loss is greatest in areas rich in trabecular bone. Preventive measures should be initiated early. It is the author's opinion that all subjects initiating treatment with prednisone at 7.5 mg or greater require calcium supplementation (diet plus supplement) at a dose of 1500 mg and vitamin D at a dose of 400 to 800 IU/d. If the patient is going to remain on this dose of glucocorticoid for more than 4 weeks, an antiresorptive agent should be started (e.g., estrogen, bisphosphonate, raloxifene). If a patient has established osteoporosis and is either initiating glucocorticoid therapy or is chronically treated with prednisone at 5 mg d or greater in addition to calcium and vitamin D supplementation, a potent antiresorptive agent (bisphosphonate) should be started. A bone mineral density measurement of either the lumbar spine or the hip may be helpful is assessing an individual's risk of osteoporosis, may improve compliance with treatment, and can be used to monitor the efficacy of the prescribed therapy. There is no reason to withhold treatment for glucocorticoid-induced bone loss until a bone mass measurement is taken, however. In motivated patients, a weight-bearing and resistance exercise program should be prescribed to help retain muscle strength and prevent depression. If hypercalciuria develops with glucocorticoid use, either thiazide diuretics or sodium restriction may be helpful. In patients who continue to lose bone or experience fracture's despite antiresorptive therapy while on glucocorticoids, bone-building anabolic agents (e.g., hPTH 1-34 or PTH 1-84) may be available someday soon.     

Suggested guidelines for evaluation and treatment of glucocorticoid-induced osteoporosis for the Department of Veterans Affairs

BACKGROUND: Glucocorticoid-induced osteoporosis is an important disorder in the predominantly male US veteran population. Department of Veterans Affairs facilities vary considerably in evaluation and management of glucocorticoid-induced osteoporosis. METHODS: We suggest how evaluation and management can take place in medical centers with and without bone mineral density measurements by dual energy x-ray absorptiometry (DXA). The proposed guidelines can be applied to other health care systems. RESULTS: Use of DXA can help determine fracture risk for patients taking glucocorticoid therapy and for those starting therapy for at least 3 months. Patients with low bone mineral density should be treated with a bisphosponate as should all patients about to start prednisone treatment at a dose of 7.5 mg/d or more. In facilities without DXA, most patients should be treated with bisphosphonates, the cost of which is about $30 to $35 per month. In addition, the use of urinary calcium measurements is encouraged to determine which patients might benefit from augmented vitamin D and calcium supplementation. CONCLUSION: Attention to fracture risk assessment in patients undergoing glucocorticoid therapy and timely bisphosphonate treatment should lead to fewer fractures.     

Clinical Question: What is the best approach to managing glucocorticoid‐induced osteoporosis?

Glucocorticoid-induced osteoporosis is common, and the resulting fractures cause significant morbidity and mortality. Rapid bone loss and increased fracture risk occur soon after the initiation of glucocorticoid therapy and are dose dependent. The increase in fracture risk is partly independent of bone mineral density, probably as a result of changes in bone material properties and increased risk of falling. Fracture risk can be assessed using the FRAX algorithm, although risk may be underestimated in patients taking higher doses of glucocorticoids. Because of the rapidity of bone loss and increase in fracture risk after the start of glucocorticoid therapy, primary prevention should be advised in high-risk individuals, for example older women and men, individuals with a previous fracture history and those with low bone mineral density. Bisphosphonates are the front-line choice for the prevention of fracture in the majority of glucocorticoid-treated patients, with teriparatide as a second-line option. Calcium and vitamin D supplements should be co-prescribed unless there is evidence of an adequate dietary calcium intake and vitamin D status.     

Role of estrogens in the management of postmenopausal bone loss

It is well known that estrogen deficiency is the major determinant of bone loss in postmenopausal women. Estrogen is important to the bone remodeling process through direct and indirect actions on bone cells. The largest clinical experience exists with estrogen therapy, demonstrating its successful prevention of osteoporosis as well as its positive influence on oral bone health, vasomotor and urogenital symptoms, and cardiovascular risk factors, which may not occur with other nonestrogen-based treatments. Compliance with HRT, however, is typically poor because of the potential side effects and possible increased risk of breast or endometrial cancer. Nevertheless, there is now evidence that lower doses of estrogens in elderly women may prevent bone loss while minimizing the side effects seen with higher doses of estrogen. Additionally, when adequate calcium, vitamin D, and exercise are used in combination with estrogen-based treatments, more positive increases occur in bone density. The benefits and risks of HRT must be assessed on a case-by-case basis, and the decision to use HRT is a matter for each patient in consultation with her physician. Estrogen-based therapy remains the treatment of choice for the prevention of osteoporosis in most postmenopausal women, and there may be a role for estrogen to play in the prevention of corticosteroid osteoporosis. Combination therapies using estrogen should probably be reserved for patients who continue to fracture on single therapy or should be used in patients who present initially with severe osteoporosis.     

Glucocorticoid-induced osteoporosis

Glucocorticoid-induced osteoporosis is the most frequent cause of secondary osteoporosis. Glucocorticoids cause a rapid bone loss in the first few months of use, but the most important effect of the drug is suppression of bone formation. The administration of oral glucocorticoid is associated with an increased risk of fractures at the spine and hip. The risk is related to the dose, but even small doses can increase the risk. Patients on glucocorticoid therapy lose more trabecular than cortical bone and the fractures are more frequent at the spine than at the hip. Calcium, vitamin D and activated forms of vitamin D can prevent bone loss and antiresorptive agents are effective for prevention and treatment of bone loss and to decrease fracture risk. Despite the known effects of glucocorticoids on bone, only a few patients are advised to take preventive measures and treat glucocorticoid-induced osteoporosis.     

Skeletal involvement in adult patients with endogenous hypercortisolism

Overt endogenous glucocorticoid excess is a well-recognized cause of bone loss and osteoporotic fractures. Cortisol excess inhibits bone formation, increases bone resorption, impairs calcium absorption from the gut, and affects the secretion of several hormones (in particular gonadotropins and GH), cytokines, and growth factors, influencing bone metabolism. The glucocorticoid excess mainly affects trabecular bone, leading to vertebral fractures in up to 70% of patients. Osteoporotic fractures may be the presenting symptom of an otherwise silent glucocorticoid excess and can precede the diagnosis of hypercortisolism by up to 2 yr. The removal of glucocorticoid excess leads to a recovery of bone mass which is, however, often incomplete and delayed, although it reduces the risk of osteoporotic fractures. Bisphosphonate therapy has been suggested to be useful in maintaining bone mass in these patients. Subclinical hypercortisolism, a condition of impaired hypothalamic- adrenal-axis homeostasis without the classical signs and symptoms of glucocorticoid excess, is a recently defined entity, which has been shown to be associated to increased bone resorption, bone loss, and high prevalence of vertebral fractures regardless of gonadal status. However, data about the effect of this subtle glucocorticoid excess on bone are still scarce and conflicting. Moreover, it is not yet known whether removing the cause of subclinical hypercortisolism leads to a recovery of bone mass and reduces the risk of osteoporotic fractures. Finally, recent data suggest that subclinical hypercortisolism is a common and underrated finding in patients with established osteoporosis. In summary, it is crucial to evaluate the risk of osteoporosis and fractures in patients with glucocorticoid excess; on the other hand, it also seems advisable to screen for glucocorticoid excess patients with osteoporotic fractures without known secondary causes of osteoporosis.     

Glucocorticoid-induced osteoporosis: mechanisms for bone loss; evaluation of strategies for prevention

Osteoporosis is a common complication of chronic glucocorticoid therapy, especially in older patients who already are at risk of having a reduced bone mass. Glucocorticoids cause bone loss by altering the bone remodeling sequence: bone resorption by osteoclasts is increased, and bone formation by osteoblasts is decreased. Serum levels of osteocalcin, a protein made by osteoblasts, are decreased with glucocorticoid therapy, further evidence of decreased osteoblast function. Glucocorticoids decrease calcium absorption by the gastrointestinal tract and increase renal calcium excretion. Several recent studies suggest that low-dose glucocorticoid therapy is not associated with bone loss. Calcium supplementation with vitamin D is recommended. Several short-term studies have shown prevention of glucocorticoid-induced bone loss with bisphosphonates, calcitonin, and progesterone. Long-term clinical trials should be undertaken to determine strategies to prevent this type of osteoporosis.     

Clinical utility of bone mass measurements in adults:Consensus of an international panel

Low bone mass predicts future fracture risk as well as high cholesterol or high blood pressure can predict the risk of heart disease or stroke. Prevention of the first fracture should be a clinical goal. In patients without fractures, osteopenia and osteoporosis can be diagnosed based on the extent of reduction in bone mass below mean peak bone mass of young healthy individuals. As bone mass decreases, fracture risk increases exponentially. Clinical situations in which an assessment of bone mass and fracture risk affects therapeutic decisions include estrogen deficiency, vertebral abnormalities, radiographic osteopenia, asymptomatic primary hyperparathyroidism, and long-term corticosteroid therapy. Serial measurements can also be used to monitor the effects of osteoporosis treatments. The appropriate technique and skeletal site for bone mass measurements should be chosen based on the patient's circumstances and the precision of measurement. A clinical interpretation can enhance the value of computer generated bone mass measurement reports and improve decision making.     

Postmenopausale und kortikoidinduzierte Osteoporose

Prevention of osteoporosis and osteoporotic fractures consists of non-drug and drug therapy. Components of non-drug therapy include improvement of muscle strength and coordination, treatment of modifiable causes of falls, a diet rich in calcium and sufficient in calories, adequate supply of vitamin D and a careful approach towards drugs known to increase falls or osteoporosis. Assessment of clinical risk factors in combination with bone mineral density measurements can identify persons at high risk of fracture who benefit most from pharmacological treatment. Particular attention should be paid to patients with previous fragility fractures and long-term oral glucocorticoid therapy.     

Postmenopausal and steroid-induced osteoporosis guideline-orientated prevention and treatment

Prevention of osteoporosis and osteoporotic fractures consists of non-drug and drug therapy. Components of non-drug therapy include improvement of muscle strength and coordination, treatment of modifiable causes of falls, a diet rich in calcium and sufficient in calories, adequate supply of vitamin D and a careful approach towards drugs known to increase falls or osteoporosis. Assessment of clinical risk factors in combination with bone mineral density measurements can identify persons at high risk of fracture who benefit most from pharmacological treatment. Particular attention should be paid to patients with previous fragility fractures and long-term oral glucocorticoid therapy.     

Skeletal morbidity in inflammatory bowel disease

Patients with Crohn's disease are at increased risk of developing disturbances in bone and mineral metabolism because of several factors, including the cytokine-mediated nature of the inflammatory bowel disease, the intestinal malabsorption resulting from disease activity or from extensive intestinal resection and the use of glucucorticoids to control disease activity. Inability to achieve peak bone mass when the disease starts in childhood, malnutrition, immobilization, low BMI, smoking and hypogonadism may also play a contributing role in the pathogenesis of bone loss. The relationship between long-term use of glucocorticoids for any disease indication and increased risk for osteoporosis and fractures is well established. However, the relationship between Crohn's disease and ulcerative colitis and bone loss remains controversial. Depending on the population studied the prevalence of osteoporosis has thus been variably reported to range from 12 to 42% in patients with inflammatory bowel disease (IBD). In IBD most studies demonstrate a negative correlation between bone mineral density (BMD) and glucocorticoid use, but not all authors agree on the relationship between long-term glucocorticoid use and continuing bone loss. Whereas prospective studies do suggest sustained bone loss at both trabecular and cortical sites in long-term glucocorticoid users with inflammatory bowel disease, a decrease in bone mass is also observed in patients with active Crohn's disease not using glucocorticoids, and bone loss is not universally observed in patients with Crohn's disease using orally or rectally administered glucocorticoids. Data on vertebral fractures are scarce and there is no agreement about the risk of non-vertebral fractures in patients with Crohn's disease, although it has been suggested that non-vertebral fracture risk may be increased by up to 60% in patients with IBD. A recent publication reports an increased risk of hip fractures in Crohn's disease related to current and cumulative corticosteroid use and use of opiates, although these fractures could not be related to the severity of osteoporosis. The issue of the magnitude of the problem of osteoporosis has become particularly relevant in Crohn's disease, since the ability of therapeutic interventions to beneficially influence skeletal morbidity has been clearly established in patients with osteoporosis, whether post-menopausal women, men or glucocorticoid users. The main question that arises is whether all patients with Crohn's disease should be treated with bone protective agents on the assumption that they all have the potential to develop osteoporosis or whether the use of these agents should be restricted to patients clearly at risk of osteoporosis and fractures, providing these can be identified. We recommend, based on the available literature and our own experience, that all patients with Crohn's disease should be screened for osteoporosis by means of a bone mineral density measurement in addition to full correction of any potential calcium and vitamin D deficiency, to allow timely therapeutic intervention of the patient at risk while sparing the vast majority unnecessary medical treatment.     

Strategies for prevention and treatment of osteoporosis at the primary, secondary, and tertiary level in Leuven, Belgium

The first strategy to prevent osteoporosis is to detect patients at risk for osteoporosis in time before fracture occurs. The known risk factors for osteoporosis can be divided according to modifiable or not modifiable, and according to vertebral or proximal femur fracture site. The importance of accumulation of several risk factor for the incidence of fragility fractures in the population is stressed. Preventive and curative therapy for osteoporosis is possible in all phases of life. Even a recent fracture should be treated, it is never too late to prevent further fractures. Strategies are proposed for the building up period of the skeleton in the adolescence (primary prevention) , for the period when accelerated bone loss starts, as in the perimenopause, during immobilisation and corticosteroid use (secondary prevention) ;and finally at the time of bone loss or fracture (tertiary prevention) . For each of these periods, general and specific therapies are listed. An algorithm for "case finding" and consequent management in clinical practice are discussed as a problem-solving and clinical reasoning exercise. A plea is made for an individualised intervention because preventive and curative treatment for osteoporosis is a long-term treatment and thus an important decision. This decision should be based on cost/benefit, pathophysiology of the case and bone active drugs. If available, it is advisable to share responsibility with an expert in the field, this will improve compliance and outcome.     

Glucocorticoid-induced osteoporosis: recent findings

The clinical features, pathogenesis and management of bone involvement in Cushing's syndrome are briefly reviewed. Personal data on bone mineral density and markers of bone turnover in Cushing's syndrome and adrenal incidentalomas are also reported. As long ago as 1932, Harvey Cushing recognized osteoporosis as a serious consequence of endogenous hypercortisolism. The introduction of cortisone in the therapy of autoimmune, rheumatic, allergic or dermatologic disorders was followed by several reports of detrimental effects on bone of patients who had undergone prolonged glucocorticoid treatment. Due to the rarity of Cushing's syndrome, most of the studies in the literature on glucocorticoid-induced osteoporosis refer to exogenous over-exposure to cortisone and its synthetic derivatives. Only a small number of works concern endogenous hypercortisolism, even if the characteristics of bone damage seem qualitatively the same. Finally, very few data are reported on the hypothetical detrimental effect on bone in the condition of the silent hypercortisolism of adrenal incidentalomas. Glucocorticoid-induced osteoporosis in Cushing's syndrome often results in vertebral fractures, and bone loss is more evident in trabecular than in cortical bone. Notwithstanding some distinctive features in osteoporosis induced by endogenous and exogenous glucocorticoid excess, the common eventual picture is notable bone damage that involves mainly the trabecular bone. Prompt and effective therapy is mandatory to reduce the risk of fractures. The present options include calcium and vitamin D supplementation, estrogen replacement therapy, bisphosphonates, either oral or parenteral. A novel approach to the clinical problem of glucocorticoid-induced osteoporosis might, in the future, be based on studies on selective glucocorticoid receptor modulators, a new class of synthetic glucocorticoids that exhibit significant anti-inflammatory and immunosuppressive activities, with reduced side effects on bone.     

Drug Insight: choosing a drug treatment strategy for women with osteoporosis-an evidence--based clinical perspective

Many randomized controlled trials (RCTs) have investigated drug treatment for women at high risk of fracture, with a reduction in fracture risk as their end point. There has also been progress in identifying women at the highest risk of fractures. The most important clinical determinant contributing to the clinical decision of initiating and choosing drug therapy for fracture prevention is a woman's fracture risk, which, in RCTs, was determined by menopausal state, age, bone mineral density, fracture history, fall risks and glucocorticoid use. Women with secondary osteoporosis were excluded, except in studies of glucocorticoid use. A second determinant of drug therapy is the evidence for fracture prevention in terms of spectrum (vertebral, nonvertebral and/or hip fractures), size and speed of effect. In the absence of head-to-head RCTs with fracture risk as the end point, however, the efficacy of antifracture drugs cannot be directly compared. Other determinants include the potential extraskeletal benefits and safety concerns of the drug, patient preferences and reimbursement issues.     

Unusual mid‐shaft fractures during long‐term bisphosphonate therapy

Background Bisphosphonates are the most commonly prescribed medications for the treatment of osteoporosis. Although existing evidence supports a good safety profile, there is concern that chronic administration of these agents could result in severe suppression of bone turnover with increased risk of nonvertebral fractures. Objective The objective of this study was to report the clinical presentation, selected bone histomorphometry and X‐ray images of patients who developed mid‐shaft long bone fractures during bisphosphonate therapy, six of whom had bone biopsy for histomorphometery. Results Of the 13 patients who sustained atraumatic mid‐shaft fractures, 10 were on alendronate and three were on risedronate therapy before the fractures. In addition to bisphosphonates, three patients were on oestrogen and two on tamoxifen concomitantly. Four patients with glucocorticoid‐induced osteoporosis were on alendronate for 3–11 years along with glucocorticoid therapy. Bone histomorphometry showed severe suppression of bone turnover in five patients and low bone turnover in one patient. Conclusion Long‐term bisphosphonate therapy may increase the risk of unusual long bone mid‐shaft fractures. This is probably due to prolonged suppression of bone turnover, which could lead to accumulation of microdamage and development of hypermineralized bone. At present, the scope of this complication in the larger context of patients receiving bisphosphonate therapy remains unknown, but appears to be small.