Bone mineral density in prepubertal asthmatics receiving corticosteroid treatment

Evaluation of vitamin D deficiency and low bone mass in children with asthma in fars province: A case-control study

Background and Aims

Asthma is a chronic inflammatory pulmonary disease which affects 10%-20% of children and adolescents. Inhaled corticosteroids (ICS) is one of its most effective therapies. The effect of systemic corticosteroids on decreasing bone mineral density (BMD) was investigated and proved in children; however, the influence of ICSs on bone density has still remained unclear. This study evaluates the bone mineral density of children and adolescents with asthma in southern Iran and the associated factors, for example, amount of used inhaled steroid.

Method

This case-control study enrolled 41 children and adolescents (aged 8-18 years) with asthma and their age and gender-matched controls in 2019-2020. Serum Calcium, phosphate, vitamin D, and bone mineral density were measured. Their physical activity, sun exposure, and fracture history were evaluated subjectively.

Results

Lumbar BMD and BMD Z-score in patients showed no significant difference with controls (p = 0.23, p = 0.73). Also, it showed that there was no significant difference in biochemical studies, growth, and bone densitometry parameters between patients who used ICSs for less than 3 months/year corticosteroid therapy compared to those with equal or more than 3 months/year usage. Prevalence of vitamin D deficiency was 28% and 8% in the controls and patients, respectively (p = 0.005).

Conclusion

The present study showed that 9.46% of children and adolescents with asthma had low bone mass for chronological age, and it is not significantly higher than normal population. Dosage of inhaled steroid did not associate with osteoporosis in these patients. Prevalence of vitamin D deficiency in patients was lower than normal population, probably due to receiving vitamin D in their routine follow-ups.

Effect of long-term medium to high-dose inhaled budesonide on bone mineral density in children with asthma: a cross-sectional study

OBJECTIVE

The objective of this study was to examine the impact of long-term medium to high-dose inhaled budesonide on bone mineral density in children with asthma.

METHODS

We conducted a cross-sectional study in children aged 7-17 years with asthma, who received long-term (≥2 years), medium to high-dose inhaled budesonide (≥400μg/day in 6-11 years old; ≥800 μg/day in >11 years old). We measured bone mineral density (BMD) using dual-energy X-ray absorptiometry and compared it with reference Indian normative values.

RESULTS

Thirty-five children with moderate to severe asthma receiving long-term medium to high-dose inhaled budesonide, were included in the study. We found a significantly low lumbar-spine BMD in the study population compared to reference Indian values (p-value 0.002). Eight cases had short stature. Despite the adjustment for height-age in these short-stature cases, lumbar-spine BMD remained significantly low in the study population (p-value 0.020). No significant difference was found in 25-hydroxy vitamin D levels between subjects with "low BMD" and "BMD z-score > -2".

CONCLUSIONS

The findings of this study suggest that long-term medium to high-dose inhaled budesonide treatment in children with asthma is associated with decreased BMD. However, further investigation with a larger sample size is necessary to confirm this relationship.

Adrenal function in cystic fibrosis

Cystic fibrosis (CF) is not known to directly affect the adrenal gland, but commonly used CF therapies do impact the function of the hypothalamic-pituitary-adrenal (HPA) axis. By binding to the glucocorticoid receptor, medications such as inhaled and oral corticosteroids can enhance the systemic effects of cortisol and result in iatrogenic Cushing syndrome. Prolonged use suppresses the body's ability to make cortisol, resulting in iatrogenic adrenal insufficiency upon medication discontinuation. Chronic use of inhaled and oral corticosteroids can negatively affect bone health, growth, and glucose metabolism. This chapter provides practical guidelines regarding the screening, diagnosis, and treatment of iatrogenic adrenal insufficiency. As the guidelines are mainly derived from the asthma literature, this chapter also highlights the need for studies to evaluate the impact of CF therapies on adrenal function and other CF-endocrinopathies.

Inhaled Corticosteroids and Endocrine Effects in Childhood

Asthma is the most common chronic inflammatory disease of children, and inhaled corticosteroids (ICSs) are the most effective and commonly used treatment of persistent asthma. ICSs currently approved for and commonly used by children with asthma include beclomethasone dipropionate, budesonide, fluticasone propionate, mometasone furoate, ciclesonide, and triamcinolone acetonide. This article reviews 4 areas critical to understanding potential adverse endocrine outcomes of ICSs and placing them in proper perspective: (1) influence of drug/delivery device properties on systemic steroid burden; (2) adrenal insufficiency during ICS treatment; (3) growth effects of ICS and asthma itself; and (4) bone mineral accretion during ICS therapy.

Bone Mineral Density to Assess Pediatric Bone Health in Drug Development

BACKGROUND

Pediatric bone health is an important part of the safety assessment of inhaled corticosteroids and certain other drugs. Current regulatory guidance for assessment of bone health for intranasal and inhaled corticosteroid drugs is a single 1-year study of linear growth.

OBJECTIVE

The objective of this study was to assess whether a significant change in bone mineral density (BMD) could be observed during a 12-month period in pediatric patients being treated for asthma with an inhaled corticosteroid using a previously conducted study.

METHODS

The publicly available information from the Childhood Asthma Management Program (CAMP) study was used to assess whether a statistically significant difference in BMD could be detected over a 1-year period. Patients who were at Tanner stage ≥2 were excluded from analysis as is stated in the present FDA Guidance on growth studies with inhaled corticosteroids, and children with any use of oral corticosteroids were also excluded. A comparison in BMD change over time (bone mineral accretion [BMA]) between baseline and 12 months of follow-up was made for the placebo and inhaled budesonide groups using multiple regression analysis to account for age, race, and gender as covariates.

RESULTS

From the original 1041 patients in the CAMP study, 74 patients met the criteria for evaluation, with 42 patients receiving budesonide and 32 placebo patients. Children randomized to budesonide had a lower mean BMA than those receiving placebo (0.021 ± 0.023 [SD] g/cm²/y vs 0.036 ± 0.025 [SD] g/cm²/y).

CONCLUSION

In a select pediatric patient population, a significant change in BMA can be observed over 12 months on an inhaled corticosteroid. Based on this post hoc analysis, measurement of BMA as an assessment of pediatric bone health may be considered for certain drugs, especially when there is a potential signal of bone toxicity from animal or human data. The clinical relevance of this finding is presently unknown, and more data on the relationship between changes in BMA and clinical pediatric bone health outcomes are needed.

The use of inhaled corticosteroids in pediatric asthma: update

Despite the availability of several formulations of inhaled corticosteroids (ICS) and delivery devices for treatment of childhood asthma and despite the development of evidence-based guidelines, childhood asthma control remains suboptimal. Improving uptake of asthma management plans, both by families and practitioners, is needed. Adherence to daily ICS therapy is a key determinant of asthma control and this mandates that asthma education follow a repetitive pattern and involve literal explanation and physical demonstration of the optimal use of inhaler devices. The potential adverse effects of ICS need to be weighed against the benefit of these drugs to control persistent asthma especially that its safety profile is markedly better than oral glucocorticoids. This article reviews the key mechanisms of inhaled corticosteroid action; recommendations on dosage and therapeutic regimens; potential optimization of effectiveness by addressing inhaler technique and adherence to therapy; and updated knowledge on the real magnitude of adverse events.

Bone mineral density and fracture risk with long-term use of inhaled corticosteroids in patients with asthma: systematic review and meta-analysis

OBJECTIVES

We aimed to assess the association between long-term use of inhaled corticosteroids (ICS) and bone adverse effects in patients with asthma.

DESIGN

Systematic review and meta-analysis of fracture risk and changes in bone mineral density with long-term ICS use in asthma.

METHODS

We initially searched MEDLINE and EMBASE in July 2013, and performed an updated PubMed search in December 2014. We selected randomised controlled trials (RCTs) and controlled observational studies of any ICS (duration at least 12 months) compared to non-ICS use in patients with asthma. We conducted meta-analysis of ORs for fractures, and mean differences in bone mineral density. Heterogeneity was assessed using the I(2) statistic.

RESULTS

We included 18 studies (7 RCTs and 11 observational studies) in the systematic review. Meta-analysis of observational studies did not demonstrate any significant association between ICS and fractures in children (pooled OR 1.02, 95% CI 0.94 to 1.10, two studies), or adults (pooled OR 1.09, 95% CI 0.45 to 2.62, four studies). Three RCTs and three observational studies in children reported on bone mineral density at the lumbar spine, and our meta-analysis did not show significant reductions with ICS use. Three RCTs and four observational studies in adults reported on ICS use and bone mineral density at the lumbar spine and femur, with no significant reductions found in the meta-analysis compared to control.

CONCLUSIONS

ICS use for ≥12 months in adults or children with asthma was not significantly associated with harmful effects on fractures or bone mineral density.

Inhaled corticosteroids in children: effects on bone mineral density and growth

Potent, topically active corticosteroids with minimum systemic activity have fewer adverse effects than do systemic corticosteroids, and can control both asthma and allergic rhinitis when given in recommended doses. However, study findings show that children with asthma receiving budesonide and beclometasone dipropionate have decreased linear growth, and that children who receive long-term inhaled corticosteroid therapy for asthma have height deficits 1-2 years after treatment initiation that persist into adulthood. The effects of inhaled corticosteroids on growth seem to be dependent on both dose and duration; the degree of systemic effects is dependent on pharmacokinetic properties (ie, absorption, distribution, and elimination), whereas the effective dose delivered is dependent on the delivery system and potency of the molecule. The effects of corticosteroids on bone mineral density in children seem to be more amenable to intervention; long-term therapy with inhaled corticosteroid therapy is safer than frequent bursts of oral corticosteroids on bone mineral accretion in this regard. Importantly, adequate nutrition (particularly sufficient intake of calcium and vitamin D) should prevent or blunt the effects of corticosteroids on bone mineral density. The potential adverse effects of inhaled corticosteroids need to be weighed against the large and well established benefit of these drugs to control persistent asthma. To minimise any adverse effects, treatment with inhaled corticosteroids should always aim to reach the lowest effective dose that gives the patient good asthma control.

Glucocorticoid-induced osteoporosis: an update on effects and management

Glucocorticoids remain a cornerstone of guideline-based management of persistent asthma and allergic diseases. Glucocorticoid-induced osteoporosis (GIO) is the most common iatrogenic cause of secondary osteoporosis and an issue of concern for physicians treating patients with inhaled or oral glucocorticoids either continuously or intermittently. Patients with GIO experience fragility fractures at better dual-energy x-ray absorptiometry T-scores than those with postmenopausal or age-related osteoporosis. This might be explained, at least in part, by the effects of glucocorticoids not only on osteoclasts but also on osteoblasts and osteocytes. Effective options to detect and manage GIO exist, and a management algorithm has been published by the American College of Rheumatology to provide treatment guidance for clinicians. This review will summarize GIO epidemiology and pathophysiology and assess the role of inhaled and oral glucocorticoids in asthmatic adults and children, with particular emphasis on the effect of such therapies on bone health. Lastly, we will review the American College of Rheumatology GIO guidelines and discuss diagnostic and therapeutic strategies to mitigate the risk of GIO and fragility fractures.

Ultrasound velocity through the tibia is not affected by prolonged inhaled steroid therapy in children

AIM

To evaluate in a prospective, cross-sectional cohort study the impact of inhaled corticosteroids (ICS) on bone speed of sound (SOS) in asthmatic children.

METHODS

Children with mild-to-moderate asthma from a pulmonary clinic were assessed over a 2-month period. We recorded clinical and demographic data related to asthma severity, its treatment, participation in sports and dairy intake. Tibial SOS was measured using the Sunlight Omnisense 7000S quantitative ultrasound bone sonometer.

RESULTS

Eighty-five mild-to-moderate asthmatic children were studied. Age range was 1.4-17 years (71.7% boys). Average disease duration was approximately 5 years, and the average cumulative duration of ICS therapy was approximately 1.5 years. Average SOS Z-score was slightly negative and varied between -3.5 and +1.9 SD. In univariate analysis, SOS Z-score was negatively correlated with asthma duration (R(2) = 5.7%, p = 0.028) and ICS duration (R(2) = 4.9%, p = 0.042). In backward stepwise multiple regression, where SOS Z-score was the dependent variable, the only variables that remained significant in the final analysis were gender (p = 0.015), asthma duration (p = 0.003) and BMI (p = 0.048) (R(2) for the model 17.52% p = 0.01).

CONCLUSION

Prolonged inhaled steroid therapy appears to have no deleterious effect upon SOS in children with mild-to-moderate persistent asthma.

Effect of long-term corticosteroid use on bone mineral density in children: a prospective longitudinal assessment in the childhood Asthma Management Program (CAMP) study

OBJECTIVE

Systemic corticosteroids are known to induce osteoporosis and increase the risk for fractures in adults and children. Inhaled corticosteroids have been shown to increase the risk for osteoporosis and fractures in adults at risk; however, long-term prospective studies of children to assess risks of multiple short courses of oral corticosteroids and chronic inhaled corticosteroids have not been performed. Thus, we assessed the effects of multiple short courses of oral corticosteroids and long-term inhaled corticosteroids on bone mineral accretion over a period of years.

METHODS

This was a cohort follow-up study for a median of 7 years of children who had mild-to-moderate asthma and initially were randomly assigned into the Childhood Asthma Management Program trial. Serial dual-energy radiograph absorptiometry scans of the lumbar spine for bone mineral density were performed for all patients. Annual bone mineral accretion was calculated for 531 boys and 346 girls who had asthma and were aged 5 to 12 years at baseline (84% of the initial cohort).

RESULTS

Oral corticosteroid bursts produced a dosage-dependent reduction in bone mineral accretion (0.052, 0.049, and 0.046 g/cm(2) per year) and an increase in risk for osteopenia (10%, 14%, and 21%) for 0, 1 to 4, and >or=5 courses, respectively, in boys but not girls. Cumulative inhaled corticosteroid use was associated with a small decrease in bone mineral accretion in boys but not girls but no increased risk for osteopenia.

CONCLUSIONS

Multiple oral corticosteroid bursts over a period of years can produce a dosage-dependent reduction in bone mineral accretion and increased risk for osteopenia in children with asthma. Inhaled corticosteroid use has the potential for reducing bone mineral accretion in male children progressing through puberty, but this risk is likely to be outweighed by the ability to reduce the amount of oral corticosteroids used in these children.

Determinants of skeletal age deviation in a cross-sectional study

OBJECTIVE

Skeletal age deviation (SAD) is associated with bone mass and fracture risk in children, but factors determining this are unknown. The aim of this population-based cross-sectional study was to describe the factors associated with SAD.

METHODS

A convenience sample of 640 male and female children aged 7-17 yr was studied. All were assessed for body composition (dual-energy x-ray absorptiometry), diet, strength, dexterity, habitual physical activity, sunlight exposure, smoking, and medication use. Skeletal age was assigned using the Tanner-Whitehouse-2 method.

RESULTS

Subjects with a SAD greater than the 75th percentile had significantly higher height, weight, and Tanner stage compared with all other subjects. Bone-free lean mass, fat mass, and grip strength were positively associated with SAD. In multivariate analysis, ever smoking and use of inhaled corticosteroids were negatively associated with SAD, whereas milk drinking was positively associated with SAD. There was no significant association between sunlight exposure, television watching, light, or strenuous exercise and SAD.

CONCLUSIONS

The results of this study should be regarded as hypothesis generating but are biologically plausible and suggest that body composition, strength, diet, ever smoking, and inhaled corticosteroid use may be determinants of bone maturity relative to age and thus affect fracture risk in children. However, more studies are necessary to explore other determinants of SAD such as genetic and perinatal factors and whether SAD influences peak bone mass.

[Inhaled corticosteroid therapy and bone metabolism in asthmatic children]

OBJECTIVE

To explore the association between inhaled corticosteroids (ICS) therapy and bone metabolism.

PATIENTS AND METHODS

The sample was composed of 151 children, aged between 1 and 17 years. There were 71 asthmatics treated with ICS for at least 6 months (group 1), 44 asthmatics treated occasionally with ICS during exacerbations (group 2), and 36 healthy children (group 3). Bone mineral density (BMD) and markers of bone formation and resorption were measured. These measures, as well as other related factors, were compared among groups. Regression models for osteopenia and BMD were used with the group as the independent variable adjusted by factors with differences between groups. A two-tailed level of p < 0.05 was used in all tests.

RESULTS

No differences in BMD were found between groups 1 and 2 but significant differences were found between groups 1 and 3 (p = 0.003). No differences were found in markers of bone formation and resorption among the groups. No association was found between BMD and the type, daily dose or accumulated dose of ICS. Group 1 showed an osteopenia odds ratio relative to group 3 of 2.94 (95 % CI: 1.49-5.78) and an average reduction of BMD of 0.50 (95 % CI: 0.32-0.68) was found from group 3 to 2 and from group 2 to 1. In group 1, markers of bone resorption significantly increased in asthmatics with osteopenia compared with those without osteopenia.

CONCLUSIONS

ICS treatment in asthmatic children seems to affect BMD. Markers of bone formation and resorption are unaffected. Osteopenia in these children could also be related to other factors that increase bone resorption.

Pediatric dual-energy X-ray absorptiometry: technique, interpretation, and clinical applications

This article reviews the dual-energy x-ray absorptiometry (DXA) technique, its interpretation, and clinical applications with emphasis on the considerations unique to pediatrics. Specifically, the use of DXA in children requires the radiologist to be a "clinical pathologist," monitoring the technical aspects of the DXA acquisition, a "statistician" knowledgeable in the concepts of Z-scores and least significant changes, and a "bone specialist," aware of the DXA findings in a large number of clinical diseases, providing the referring clinician with a meaningful context for the numeric result obtained with DXA.

Pediatric DXA: clinical applications

Normal bone mineral accrual requires adequate dietary intake of calcium, vitamin D and other nutrients; hepatic and renal activation of vitamin D; normal hormone levels (thyroid, parathyroid, reproductive and growth hormones); and neuromuscular functioning with sufficient stress upon the skeleton to induce bone deposition. The presence of genetic or acquired diseases and the therapies that are used to treat them can also impact bone health. Since the introduction of clinical DXA in pediatrics in the early 1990s, there has been considerable investigation into the causes of low bone mineral density (BMD) in children. Pediatricians have also become aware of the role adequate bone mass accrual in childhood has in preventing osteoporotic fractures in late adulthood. Additionally, the availability of medications to improve BMD has increased with the development of bisphosphonates. These factors have led to the increased utilization of DXA in pediatrics. This review summarizes much of the previous research regarding BMD in children and is meant to assist radiologists and clinicians with DXA utilization and interpretation.

Clinical safety of inhaled corticosteroids for asthma in children: an update of long-term trials

Inhaled corticosteroids are established as the mainstay of maintenance therapy for chronic asthma. However, there remains some debate regarding the safety of long-term use of these agents, particularly in children. This concern mainly stems from the findings of short-term studies assessing the effects of inhaled corticosteroids on lower leg growth rate or the hypothalamic-pituitary-adrenal axis. However, the clinical relevance of these findings to long-term treatment is unknown and significant uncertainty exists regarding the predictive value of changes in cortisol levels and clinically relevant changes in growth or bone mineral density. To assess the safety of long-term use of inhaled corticosteroids in children with asthma, a systematic review of the literature was performed focusing on randomised, controlled studies of >or=12 months' duration, to obtain data with maximum relevance to clinical practice. Specific searches were conducted to identify studies examining each of the following three areas: growth, bone mineral density and cortisol levels. Fourteen studies met the inclusion criteria for statural growth, four for bone mineral density, and ten for cortisol levels. There was some evidence of a small decrease in statural growth during the initial period of inhaled corticosteroid therapy. This effect was more marked at daily doses of >200 microg and did not apply to all treatment regimens. Studies examining final attained adult height found no difference between patients treated with inhaled corticosteroids and those receiving nonsteroidal therapy. None of the studies investigating effects on bone mineral density found any adverse effects of inhaled corticosteroid therapy. Finally, recommended doses of inhaled corticosteroids generally had little or no effect on plasma- or urinary-cortisol levels versus nonsteroidal therapy. In conclusion, this literature review supports the theory that recommended doses of inhaled corticosteroids can be administered to children for the long-term management of asthma with minimal risk of clinically relevant adverse effects on growth, bone density or cortisol levels.

Sung JJ, K. Lam CW. Steroid-induced osteonecrosis in severe acute respiratory syndrome: a retrospective analysis of biochemical markers of bone metabolism and corticosteroid therapy

Aim

We investigated the effect of massive doses of corticosteroid therapy on bone metabolism using specific biochemical markers of bone metabolism, and the prevalence of osteonecrosis in severe acute respiratory syndrome (SARS) patients at a university teaching hospital in Hong Kong.

Methods

Seventy-one patients with a clinical diagnosis of SARS were studied according to the modified World Health Organization case definition of SARS who were involved in the SARS epidemic between 10 March and 20 June 2003. The clinical diagnosis was confirmed by serological test and/ or molecular analysis. Biochemical markers of bone metabolism were analysed retrospectively using serial clotted blood samples collected from each patient during the course of hospital admission to discharge and subsequent follow-up at out-patient clinic using the arbitrary time periods: (i) Day <10; (ii) Day 28-44; (iii) Day 51-84; and (iv) Day >90 after the onset of fever. Magnetic resonance imaging of the knee and hip joints were performed post-admission to evaluate the prevalence of osteonecrosis amongst these SARS patients. Various risk factors for the development of osteonecrosis were assessed using receiver operating characteristics curve comparison with appropriate test statistics and Spearman’s coefficients of rank correlation with biochemical bone markers.

Results

Biochemical markers of bone metabolism showed significant bone resorption as evidenced by a marked increase in serum C-terminal telopeptide concentration (CTx) from Day 28-44 after the onset of fever. With tapering down of corticosteroid dosage, CTx started to return to previous baseline level from Day 51 onwards, while other bone formation markers, serum osteocalcin and bone- specific alkaline phosphatase concentrations (OC and BALP, respectively), started to increase. The latter effect was even more marked after Day >90. Seven patients developed radiological evidence of osteonecrosis. The prevalence of osteonecrosis in this cohort was 9.9%. A total corticosteroid dosage of >1900mg hydrocortisone, >2000 mg methylprednisolone, >13 340 mg hydrocortisone-equivalent corticosteroid therapy, and >18 days on corticosteroid therapy were found to be significant risk factors for the subsequent development of osteonecrosis. There were also significant positive correlations amongst various biochemical bone markers in this patient cohort.

Conclusion

Both bone resorption and formation markers were unable to predict the subsequent development of osteonecrosis. The use of high dose of hydrocortisone or methylprednisolone for an extended duration was shown to be a significant risk factor for osteonecrosis. Its prevalence in this cohort is comparable to those reported in the literature for SARS patients with high-dose corticosteroid therapy. The Day 28–44 increase in the serum CTx coincided with the timing of corticosteroid use. The Day >51 increase in serum OC and BALP coincided with the timing of corticosteroid withdrawal.

Secondary osteoporosis

Secondary osteoporosis occurs as a consequence of various lifestyle factors (eg, eating disorders, smoking, alcoholism), disease processes (eg, endocrinopathies, gastrointestinal tract disease, hepatobiliary disease), and treatment regimens that comprise corticosteroids or chemotherapeutic agents. Some of the disease entities underlying secondary osteoporosis may be clinically silent and identified only during evaluation for documented osteoporosis. The pathogenesis of osteoporosis in these settings is typically multifactorial. The loss of bone may be direct or indirect but ultimately is related to altered osteoblast or osteoclast function. Causes of secondary osteoporosis should especially be investigated in men at all ages and in premenopausal women with atraumatic fractures. In addition, patients with known risk factors should be evaluated. Early recognition and intervention are essential to prevent further loss of bone mass and to prevent fragility fractures.

Inhaled corticosteroids, bone mineral density and fracture in older people

The efficacy of inhaled corticosteroids in the treatment of asthma has been firmly established in a variety of settings. The majority of asthma management plans now recommend the use of inhaled corticosteroids at an early stage. This means that most patients with asthma will be prescribed an inhaled corticosteroid at some point in time and many patients with asthma will use these drugs for several years. Inhaled corticosteroids are also used in the treatment of other conditions, particularly chronic obstructive pulmonary disease (COPD). Since inhaled corticosteroids are absorbed into the systemic circulation, they can have systemic adverse effects, such as suppression of the hypothalamic-pituitary-adrenal axis and increasing the risk of bruising. However, perhaps the greatest concern for patients is whether the regular use of inhaled corticosteroids has an adverse impact on the bone mineral density and increases the risk of fracture. There is now accumulating evidence from epidemiological studies that the use of inhaled corticosteroids is inversely related to bone mineral density in a dose-dependent fashion. However, data from two clinical trials of moderately high doses of inhaled corticosteroids in patients with COPD have produced conflicting results and while the larger study of triamcinolone found a significant impact of this drug on bone mineral density, a smaller study of budesonide found no effect. Epidemiological research into the relationship between inhaled corticosteroids and fracture is at an early stage. To date, only three studies in this area have been reported, all of which have used different approaches to try to minimise the impact of bias and confounding. There is a lack of consistency between the final estimates of the impact of inhaled corticosteroids on fracture risk. However, taken together these data suggest that the short to medium term use of inhaled corticosteroids is associated with a small adverse effect on bone. Doctors and patients need to be aware of this risk and balance it against the known beneficial effects of inhaled corticosteroids.

Bone mineral density at diagnosis and following successful treatment of pediatric Cushing's disease

Bone mineral density (BMD) is frequently reduced in children and adolescents with Cushing's disease (CD), but there is little follow-up data after cure. BMD was determined by dual energy X-ray absorptiometry (DEXA) in two groups of patients with CD. Group 1 comprised 8 patients, 5 males and 3 females, aged 12.4 yr (8.2-16.8), assessed at diagnosis. Group 2 comprised 11 subjects, 6 males and 5 females, diagnosed at age 13.3 yr (6.4-17.4), cured by transsphenoidal surgery (TSS) (no.=7) or TSS + pituitary irradiation (no.=4). They had measurement of BMD, at mean age of 18.3 yr (11.1-28.5), i.e. 4.5 yr (0.8-11.4) after cure. Four patients, mean age 20.2 yr (17.6-22.4), had repeated DEXA'scans, 1-4 times, for up to 5.8 yr. After cure, GH deficiency was present in 9 patients and treated with hGH in 8. In Group 1, patients' L2-L4 volumetric (v)BMD Z-score was variable with a mean of -1.04 (-3.21-0.11). L2-L4 vBMD Z-score values correlated negatively with midnight cortisol (p < 0.05). In Group 2, mean L2-L4 vBMD was -0.38 (-1.0-0.13); and in 7/11, mean femoral neck (FN) areal (a)BMD Z-score was 0.14 (-1.62-2.46). FN aBMD Z-score was higher than L2-L4 aBMD Z-score (p < 0.05). In patients with repeated scans, mean change in L2-L4 vBMD Z-score was 0.20 (-0.15-0.45), and mean change in FN aBMD Z-score 0.03 (-0.53-0.38). These findings show variability of BMD at diagnosis and near normal BMD after cure of pediatric CD, suggesting that with appropriate replacement of pituitary hormone deficiency normal peak bone mass is achievable.

Effects of once-weekly oral alendronate on bone in children on glucocorticoid treatment

OBJECTIVES

To determine the effects of once-weekly oral alendronate on indices of bone size, density and resorption in children with chronic illness being treated with glucocorticoids.

METHODS

Twenty-two children with chronic illness treated with prednisone were randomized to receive 1 year's treatment with either once-weekly oral placebo or alendronate (1-2 mg/kg body weight) in a double-blind study. The main outcome measures were changes in lumbar spine and femoral shaft size and volumetric density (measured by dual energy X-ray absorptiometry) and N-telopeptide excretion (a marker of bone resorption).

RESULTS

Once-weekly alendronate was well tolerated, and there were no major adverse events. In both groups bone size and bone mineral content increased through growth. Volumetric bone density of the lumbar spine increased significantly in the alendronate group (P = 0.013), but not in the placebo group. There were no differences between the groups in growth in the cortical width of the femoral shaft, but the cross-sectional moment of inertia per unit length-a derived estimate of mechanical strength-increased significantly in the alendronate group (P = 0.014) but not in the placebo group. Urine N-telopeptide excretion was suppressed significantly in the alendronate group (P = 0.007) but not in the placebo group. Height velocity was positively correlated with changes in both lumbar spine area and the total width of the femoral shaft (P = 0.015, P = 0.026, respectively).

CONCLUSION

Once-weekly oral alendronate is well tolerated, suppresses bone resorption and may improve volumetric bone density at the lumbar spine and mechanical strength of the femoral shaft in children with chronic illness taking glucocorticoids. It does not affect bone growth. Larger controlled studies are needed to determine if these changes translate into reduced fracture incidence or greater peak bone mass. This study highlights the importance of differentiating between changes in bone size and changes in volumetric bone density in assessing bone in children, and also having control subjects in intervention studies.

Biochemical markers of bone metabolism and calciuria with inhaled budesonide therapy

We investigated the changes in renal excretion of calcium, sodium, and potassium in asthmatic children treated with inhaled budesonide, an inhaled glucocorticoid. Twenty-two asthmatic patients (7 female, 15 male, mean age 10.1+/-4.3 years) treated with 400-600 microg/day inhaled budesonide and 23 healthy children (6 female, 17 male, mean age 10.2+/-2.8 years) were enrolled in the study. The parameters recorded were serum sodium, potassium, calcium, phosphorus, alkaline phosphatase (ALP), type I collagen carboxyterminal telopeptide (ICTP), osteocalcin, intact parathyroid hormone (PTH) levels, first spot morning urine calcium/creatinine ratio, sodium/potassium ratio, and daily renal calcium excretion rate (UCa-ER). These parameters were measured in the control group and pre- and post-budesonide treatment in asthmatic children. Serum electrolytes, ALP, PTH, ICTP, and UCa-ER were in the normal ranges and were not significantly different between controls and asthmatic children. Serum levels of ICTP increased, while levels of osteocalcin decreased after budesonide therapy in the asthmatic group ( P=0.001, P=0.005). UCa-ER was decreased after budesonide therapy in asthmatics ( P=0.000). In conclusion, moderate doses of inhaled budesonide cause hypocalciuria and decreased bone turnover. These results may be attributed to a mechanism compensating for decreased absorption of calcium in the gut due to the topical effect of swallowed budesonide rather than the systemic effects of the drug. Increased bone metabolism and decreased turnover may have an important role in this compensatory mechanism.

Effect of high-dose fluticasone propionate on bone density and metabolism in children with asthma

Significant concern remains over the long-term side effects of inhaled steroids. This cross-sectional study evaluates the effect of high-dose inhaled fluticasone propionate (FP) on biochemical markers of bone metabolism and bone density in children with asthma. Children with chronic asthma using FP >/= 1,000 mcg daily for at least 6 months, and healthy controls, were entered in the study. No children had taken oral prednisolone within the previous month. Fasting morning serum was analyzed for bone formation markers, and spot urine for bone resorption markers. Dual-energy X-ray absorptiometry (DEXA) results were reviewed in a subgroup of patients. Forty-nine children with asthma and 32 controls were recruited. The mean FP dose was 771.2 +/- 253.35 mcg/m2/day. Unpaired t-test analysis revealed no significant difference in biochemical markers studied. In subjects with asthma; 13 of 37 (35.1%) had lumbar spine density more than one standard deviation below the mean (P = 0.001). This fell to 6/37 (16.2%) with bone age correction (NS). In conclusion, no significant reduction in bone metabolism or bone age-corrected bone mineral density was observed in children with asthma on prolonged high doses of inhaled FP.

Safety of the newer inhaled corticosteroids in childhood asthma

Inhaled corticosteroids (ICS) remain a vital part of the management of persistent asthma, but concerns have been raised about their potential adverse effects in children. This review examines the safety data on three new ICS - fluticasone propionate, mometasone, and extrafine beclomethasone in hydrofluoroalkane (HFA-134a) propellant (QVAR The use of tradenames is for product identification purposes only and does not imply endorsement. formulation) in relation to the older corticosteroids. Topical adverse effects such as thrush and dysphonia are rare, but dental erosion is a possibility with powder forms of ICS because of their low pH. Thus, it is important to stress mouth rinsing after administration and maintaining good dental hygiene to minimize this risk. Biochemical adrenal suppression can be readily demonstrated, particularly with high doses of all ICS. The clinical relevance of this was uncertain in the past, but there have now been >50 reported cases of acute adrenal crises in children receiving ICS, most of whom were on fluticasone propionate. In order to minimize the risk of symptomatic adrenal suppression, it is important to back-titrate the ICS dose and alert families of children receiving high-dose ICS of this potential adverse effect. A pediatric endocrine opinion should be sought if adrenal suppression is suspected. The older ICS cause temporary slowing of growth velocity, but the limited data available do not show any significant compromise of final adult height. The effect on growth of fluticasone propionate may not be as great as with the older ICS, but the studies have been short term and only used low doses of fluticasone propionate. There have been case reports of growth suppression in children receiving high doses of fluticasone propionate. The limited studies performed on the effect of ICS on bone mineral density in children did not show any adverse effects, but there may be an increased risk of fractures. Hydrofluoroalkane beclomethasone (QVAR) is essentially the same drug as chlorofluorocarbon beclomethasone, but with double the lung deposition owing to the smaller particle size. Thus, it could be expected that any adverse effects seen with chlorofluorocarbon beclomethasone would be the same with hydrofluoroalkane beclomethasone. However, some of the published data, particularly in adults, suggest that hydrofluoroalkane beclomethasone may be less systemically active than chlorofluorocarbon beclomethasone, even at equipotent doses. As yet, there are no long-term data on mometasone, but initial studies in adults suggest there may be less suppression of the hypothalamic-pituitary-adrenal axis, although further studies are required, particularly in children.ICS will remain a cornerstone in the management of persistent pediatric asthma, provided that the diagnosis of asthma is secure. It is very important to use ICS appropriately and to ensure the lowest possible doses are used to achieve symptom control, thus minimizing the risk of serious adverse effects.

Inhaled corticosteroids effects on bone in asthmatic and COPD patients: a quantitative systematic review

Deleterious effect of oral corticosteroids on bone has been well documented, whereas this remains debated for inhaled ones (ICS). Our objectives were to analyze the effects of ICS on bone mineral density, fracture risk and bone markers. We performed an exhaustive systematic research of all controlled trials potentially containing pertinent data, peer-reviewed by a dedicated WHO expert group, and comprehensive meta-analyses of the data. Inclusion criteria were ICS, and BMD/markers/fractures in asthma/chronic obstructive pulmonary diseases (COPD) and healthy patients. Analyses were performed in a conservative fashion using professional dedicated softwares and stratified by outcome, study design and ICS type. Results were expressed as standardized mean difference/effect size (ES), relative risk (RR) or odds ratio (OR), depending on study design and outcome units. Publication bias was investigated. Twenty-three trials were reviewed; 11 papers fit the inclusion criteria and were assessed for the main analysis. Quality scores for the randomized controlled trials (RCTs) were 80%, 71% for the prospective cohort studies, and 78% for the retrospective cohort and cross-sectional studies. We globally assessed ICS effects on BMD and found deleterious effects: ES=0.61 ( p=0.001) for healthy subjects, and ES=0.27 ( p<0.001) for asthma/COPD patients. For these patients, this effect was 0.21 ( p<0.01) at the lumbar spine, and 0.26 ( p<0.001) at the hip or femoral neck. A single study evaluated the impact of ICS on hip fracture and reported an increased OR of 1.6 (1.24; 2.03). Lumbar fracture rate differences did not reach the level of statistical significance: 1.87 (0.5; 6.94). Osteocalcin and PICP were decreased and ICTP, pyridinoline and deoxypyridinoline levels were not significantly affected. Budesonide (BUD) appeared to be the ICS inducing the less deleterious effects on bone, followed by beclomethasone dipropionate (BDP) and triamcinolone (TRI). Publication bias investigation provided non-significant results. In our meta-analyses, BUD at a mean daily dose (SD) of 686 microg (158 microg), BDP at 703 microg (123 microg) and TRI at 1,000 microg (282 microg) were found to affect bone mineral density and markers in patients suffering from the two major respiratory diseases. These findings could have practical implication in the long-term management of asthmatic and COPD patients.

In vivo rat assay: bone remodeling and steroid effects on juvenile bone by pQCT quantification in 7 days

Anesthetized Sprague-Dawley weanling rats were scanned for bone mineral density (BMD) values after 7 days of treatment to determine whether resorption/growth at the proximal tibia can be quantified by peripheral quantitative computed tomography scanning techniques. Because the weanling rat is in a rapid growth stage, all groups showed significant increases in change from baseline values of BMD. Bisphosphonate treatment produced significant dose-related changes in BMD with average increases of 195 and 241% (10 and 20 microg/kg) vs. 86% in control rats. We further characterized this model to determine effects of steroids on growing bone. Graded doses of glucocorticoid (3.5, 7.0, 10.5, 14.0, 28.0, and 42.0 mg x kg(-1) x wk(-1)) caused no significant differences in trabecular BMD in 7 days between control and treated rats. Significant decreases in growth (weights) and increases in cortical bone area were observed, indicating that this model may be useful in comparing effects of nonsteroid, anti-inflammatory alternatives on juvenile bone. Although the relevance of this model to adult disease remains to be elucidated, it also provides a tool for mechanistic evaluation of therapeutic modalities or efficacy assessment for dose selection for longerterm models.

Four-year gain in bone mineral in girls with and without past forearm fractures: a DXA study. Dual energy X-ray absorptiometry

We have previously shown that girls with a recent distal forearm fracture have weaker skeletons than girls who have never fractured. This could be a transient or persistent phenomenon. The present study was undertaken to determine whether the bone mineral content (BMC) of girls with previous distal forearm fractures remains lower 4 years postfracture or if catch-up gain has occurred. We report baseline and follow-up dual energy X-ray absorptiometry (DXA) results for 163 girls: 81 girls from the original control group who remained free of fracture (group 1) and 82 girls from the original group with distal forearm fractures (group 2). In data adjusted for bone area, height, weight, and pubertal status, group 2 girls had 3.5-8.5% less BMC at the total body, lumbar spine, ultradistal radius, and hip trochanter than group 1 at baseline, and 2.4-5.7% less BMC at these sites at follow-up. Even girls from group 2 who did not experience another fracture after baseline (n = 58) did not display greater BMC at follow-up compared with baseline values at any site, indicating that the decreased BMC at the time of fracture had persisted. In group 2, the relative gain in BMC after adjusting for the initial BMC and current bone area, height, weight, and pubertal stage was less than or similar to, but not greater than that of group 1 (ratio [95% CI]: total body, 0.985 [0.972-0.998]; lumbar spine, 0.961 [0.935-0.987]; ultradistal radius, 0.968 [0.939-0.998]; hip trochanter, 0.955 [0.923-0.988]; femoral neck, 0.981 [0.956-1.007]; and 33% radius 0.999 [0.977-1.021]). These findings indicate that girls with distal forearm fractures do not improve their gain of BMC. We conclude that girls who have sustained a distal forearm fracture maintain their lower BMC at most sites for at least 4 years.

Safety of inhaled corticosteroids in children with asthma

Inhaled corticosteroids (ICS) have become the mainstay of therapy in chronic childhood asthma. Despite the long history and the documented efficacy of these drugs in controlling asthma, concerns still abound regarding the safety of these drugs in children, most specifically related to the potential for adrenal suppression and growth retardation. Recently published studies suggest that adrenal function remains intact when low and moderate doses of these drugs are used. Long-term studies of growth in children suggest that despite an initial decrease in growth velocity, ultimate adult height is not affected significantly by the use of ICS. Other complications of glucocorticoids are not usually seen with low and moderate doses. With proper monitoring and follow-up observation, asthma control can be achieved with these drugs in a safe and effective manner.