Osteoporosis in steroid-dependent asthma

Exploring and explaining low participation in physical activity among children and young people with asthma: a review

Background

Asthma is the most common chronic illness among children and accounts for 1 in 5 of all child GP consultations. This paper reviews and discusses recent literature outlining the growing problem of physical inactivity among young people with asthma and explores the psychosocial dimensions that may explain inactivity levels and potentially relevant interventions and strategies, and the principles that should underpin them.

Methods

A narrative review based on an extensive and documented search of search of CinAHL, Embase, Medline, PsycINFO and the Cochrane Library.

Results & Discussion

Children and young people with asthma are generally less active than their non-asthmatic peers. Reduced participation may be influenced by organisational policies, family illness beliefs and behaviours, health care advice, and inaccurate symptom perception and attribution. Schools can be reluctant to encourage children to take part in physical education or normal play activity due to misunderstanding and a lack of clear corporate guidance. Families may accept a child's low level of activity if it is perceived that breathlessness or the need to take extra inhalers is harmful. Many young people themselves appear to accept sub-optimal control of symptoms and frequently misinterpret healthy shortness of breath on exercising with the symptoms of an impending asthma attack.

Conclusion

A multi-faceted approach is needed to translate the rhetoric of increasing activity levels in young people to the reality of improved fitness. Physical activity leading to improved fitness should become part of a goal orientated management strategy by schools, families, health care professionals and individuals. Exercise induced asthma should be regarded as a marker of poor control and a need to increase fitness rather as an excuse for inactivity. Individuals' perceptual accuracy deserves further research attention.

Melatonin

Melatonin is a ubiquitous molecule and widely distributed in nature, with functional activity occurring in unicellular organisms, plants, fungi and animals. In most vertebrates, including humans, melatonin is synthesized primarily in the pineal gland and is regulated by the environmental light/dark cycle via the suprachiasmatic nucleus. Pinealocytes function as 'neuroendocrine transducers' to secrete melatonin during the dark phase of the light/dark cycle and, consequently, melatonin is often called the 'hormone of darkness'. Melatonin is principally secreted at night and is centrally involved in sleep regulation, as well as in a number of other cyclical bodily activities. Melatonin is exclusively involved in signaling the 'time of day' and 'time of year' (hence considered to help both clock and calendar functions) to all tissues and is thus considered to be the body's chronological pacemaker or 'Zeitgeber'. Synthesis of melatonin also occurs in other areas of the body, including the retina, the gastrointestinal tract, skin, bone marrow and in lymphocytes, from which it may influence other physiological functions through paracrine signaling. Melatonin has also been extracted from the seeds and leaves of a number of plants and its concentration in some of this material is several orders of magnitude higher than its night-time plasma value in humans. Melatonin participates in diverse physiological functions. In addition to its timekeeping functions, melatonin is an effective antioxidant which scavenges free radicals and up-regulates several antioxidant enzymes. It also has a strong antiapoptotic signaling function, an effect which it exerts even during ischemia. Melatonin's cytoprotective properties have practical implications in the treatment of neurodegenerative diseases. Melatonin also has immune-enhancing and oncostatic properties. Its 'chronobiotic' properties have been shown to have value in treating various circadian rhythm sleep disorders, such as jet lag or shift-work sleep disorder. Melatonin acting as an 'internal sleep facilitator' promotes sleep, and melatonin's sleep-facilitating properties have been found to be useful for treating insomnia symptoms in elderly and depressive patients. A recently introduced melatonin analog, agomelatine, is also efficient for the treatment of major depressive disorder and bipolar affective disorder. Melatonin's role as a 'photoperiodic molecule' in seasonal reproduction has been established in photoperiodic species, although its regulatory influence in humans remains under investigation. Taken together, this evidence implicates melatonin in a broad range of effects with a significant regulatory influence over many of the body's physiological functions.

Melatonin effect on bone metabolism in rats treated with methylprednisolone

The present study was undertaken to examine the effect of melatonin (25 microg/mL of drinking water, about 500 microg/day) on a 10-wk long treatment of male rats with methylprednisolone (5 mg/kg s.c., 5 days/wk). Bone densitometry and mechanical properties, calcemia, phosphatemia and serum bone alkaline phosphatase activity and C-telopeptide fragments of collagen type I (CTX) were measured. Both melatonin and methylprednisolone decreased significantly body weight (BW) and the combination of both treatments resulted in the lowest BW values found. Consequently, all results were analyzed with BW as a covariate. Densitometrically, methylprednisolone augmented bone mineral content (BMC), bone area (BA) and bone mineral density (BMD) in the entire skeleton, BMC in cortical bone, and BMC and BMD in trabecular bone. Melatonin increased BMC and BA in whole skeleton and BMC and BMD in trabecular bone. For BMC and BA of whole skeleton, BMC of cortical bone, and BMC and BMD of trabecular bone, the combination of glucocorticoids and melatonin resulted in the highest values observed. Femoral weight of rats receiving methylprednisolone or melatonin increased significantly and both treatments summated to achieve the greatest effect. In femoral biomechanical testing, methylprednisolone augmented ultimate load and work to failure significantly. Rats receiving the combined treatment of methylprednisolone and melatonin showed the highest values of work to failure. The circulating levels of CTX, an index of bone resorption, decreased after methylprednisolone or melatonin, both treatments summating to achieve the lowest CTX values found. Serum calcium increased after methylprednisolone and serum phosphorus decreased after treatment with methylprednisolone or melatonin while serum bone alkaline phosphatase levels remained unchanged. The results are compatible with the view that low doses of methylprednisolone or melatonin decrease bone resorption and have a bone-protecting effect.

Secondary osteoporosis: underlying disease and the risk for glucocorticoid-induced osteoporosis

BACKGROUND

Chronic diseases of many organ systems require long-term (>or=1 year) treatment with glucocorticoids. Owing to the catabolic activity of glucocorticoid therapy, osteoporosis is a potential complication.

OBJECTIVES

This review discusses glucocorticoid-induced bone loss and the factors, including underlying disease, that increase the risk for osteoporosis. Therapeutic options for the prevention and treatment of glucocorticoid-induced osteoporosis (GIO) also are reviewed.

METHODS

A review of the English-language literature was conducted using the MEDLINE database and proceedings from scientific meetings. Search terms including glucocorticoid-induced osteoporosis, bone loss, and fracture were used to refine the search, and preference was given to studies published after 1990.

RESULTS

Long-term glucocorticoid treatment causes bone loss that is most precipitous in the first 6 months. Patients treated with glucocorticoids have additional risk factors for bone loss and osteoporosis that are associated with their primary disease. Chronic diseases can cause changes in bone metabolism, leading to bone loss in addition to that induced by glucocorticoids alone. Bone loss can be minimized through proper nutrition, weight-bearing exercise, calcium and vitamin D supplementation, and, where indicated, bisphosphonate treatment. The American College of Rheumatology Ad Hoc Committee on Glucocorticoid-Induced Osteoporosis guidelines recommend bisphosphonates for minimizing bone loss and fracture risk in patients at risk for GIO. Risedronate is indicated for the prevention and treatment of GIO, and alendronate is indicated for its treatment. Both risedronate and alendronate increase bone mineral density in patients at risk for GIO. Risedronate significantly reduces the incidence of vertebral fractures after 1 year of treatment (P<0.05). The effectiveness and tolerability of the bisphosphonates have not been established in pregnant women or pediatric patients.

CONCLUSIONS

Men and women initiating long-term glucocorticoid treatment and those with GIO should be concomitantly treated with effective osteoporosis therapy to reduce fracture risk and counseled on preventive lifestyle changes.

Glucocorticoid-induced osteoporosis

Therapeutic use of glucocorticoids can lead to many well-known adverse events. Of all potential serious side effects, glucocorticoid-induced osteoporosis (GIOP) is one of the most devastating complications of protracted glucocorticoid therapy in rheumatoid arthritis. GIOP is the most common form of drug-induced osteoporosis. Although much has been written about the association of glucocorticoids with bone disease among patients with chronic inflammatory conditions, many issues remain unsettled. This article focuses on areas of continued controversies, including the epidemiology and pathogenesis of GIOP, specification of a "safe" dose, methods for diagnosis of GIOP, and an evidence-based approach for GIOP prevention.

Effects of methylprednisolone on bone formation and resorption in rats

Excessive glucocorticoids induce osteoporosis. However, there is some controversy regarding the mechanism of action, and even the endpoint result. The present study was carried out to obtain further insight into the action of glucocorticoids on bone formation and resorption in rats. Growing rats were injected subcutaneously with methylprednisolone (mPSL) at doses of 0, 2.5, 5, 10 or 20 mg/kg per day for 4 weeks. Bone mineral density (BMD), enchondral and periosteal bone formation, collagen synthetic activities of osteoblasts, numbers of osteoblasts and osteoclasts, and serum markers to assess bone turnover were determined. Administration of mPSL dose-dependently increased the BMD in the tibial metaphysis, while it dose-dependently decreased the BMD in the diaphysis. Both enchondral and periosteal bone formation were decreased in a dose-dependent fashion. The incorporation and secretion of (3)H-proline by osteoblasts were both decreased in trabecular and cortical bones. The number of osteoclasts, together with the number of osteoblasts, in the tibial metaphysis was drastically decreased. Serum alkaline phosphatase and osteocalcin were decreased at higher doses. These results support the recent notion that glucocorticoids inhibit both bone formation and resorption. In addition, BMD as an endpoint result might differ from site to site in bone due to a different balance between bone formation and resorption.

Dual energy X-ray absorptiometry outcomes in male COPD patients after treatment with different glucocorticoid regimens

STUDY OBJECTIVES

To compare bone mineral density (BMD) outcomes of patients who received continuous oral systemic glucocorticoids (GCs) with BMD outcomes of patients who received multiple GC courses, oral or IV.

DESIGN

Cross-sectional study.

PARTICIPANTS

Eighty-six white men with COPD selected from the outpatient clinic for pulmonary diseases.

INTERVENTION

Data analysis from medical records, bone densitometry, and pulmonary function tests of consecutive selected patients. Inclusion period into the study was exactly 1 year.

MEASUREMENTS AND RESULTS

Ten patients received oral prednisolone daily (group 1). Eleven patients were treated for several exacerbations with multiple systemic prednisolone courses, up to a period of 2 weeks per course, with a cumulative dose of > or = 1,000 mg (group 2). Likewise, 28 patients were treated with multiple systemic prednisolone courses, but with a cumulative dose < 1,000 mg (group 3). Thirty-seven patients were never treated with systemic prednisolone, and partly with inhaled corticosteroids (ICS) [group 4]. All groups were balanced for age and pack-years of smoking. In group 2, body mass index (BMI) and FEV(1) were lowest and hyperinflation was highest. The cumulative systemic prednisolone dose was highest in group 1, irrespective of the additional ICS treatments. Dual energy x-ray absorptiometry scanning of the lumbar spine, total hip, and femoral neck regions revealed a T score < or = 2.5 SD in 27 patients (31%), 31 patients (36%), and 34 patients (40%), respectively. BMD outcomes at any site were lower in patients receiving multiple systemic prednisolone courses > 1,000 mg, cumulatively (group 2), compared to the other groups, and these values were (mean +/- 1 SD) 0.759 +/- 0.238 g/cm(2), 0.683 +/- 0.115 g/cm(2), and 0.686 +/- 0.125 g/cm(2), respectively (p < 0.0001). Multivariate regression analysis revealed a correlation between the cumulative dose of prednisolone in group 2 and BMD of the lumbar spine (adjusted r = 0.48; p < 0.01). At the total hip and femoral neck regions, only a correlation between BMI and BMD was observed (adjusted r = 0.65 and 0.58, respectively; p < 0.0001 for both sites).

CONCLUSIONS

Despite a far lower cumulative GC dose in comparison with patients treated with systemic corticosteroids continuously, after adjusting for BMI and lung function, osteoporosis of the lumbar spine was most frequent in patients receiving > 1,000 mg of prednisolone cumulatively, administered in multiple courses for the treatment of exacerbations of COPD.

Therapeutic significance of distal airway inflammation in asthma

Inflammation in asthma is not merely confined to the large central airways but also extends to the small peripheral airways. Distal lung inflammation can be observed even in patients with asthma with mild disease and normal spirometric readings. Subjects with asymptomatic asthma can exhibit significant increases in peripheral airway resistance, likely the result of distal lung inflammation. As determined from measurements of eosinophilic and other cellular infiltrates, the inflammatory response in the distal lung can exceed that in the large airways. Nocturnal asthma, a natural model of cyclic asthma worsening, is associated with an increase in nighttime distal lung inflammation, as evidenced by the accumulation of alveolar tissue eosinophils. Distal lung disease appears to increase the risk of recurrent asthma exacerbation, whereas disease-related anatomic changes in the small airways of the distal lung are prominent in fatal asthma. The clinical significance of distal lung disease makes this region an important therapeutic target. Chlorofluorocarbon (CFC)-based preparations of inhaled corticosteroids used to treat airway inflammation produce aerosols of relatively large particle size (approximately 4 microm); such aerosols have poor access to the distal lung. New formulations of inhaled corticosteroids that use hydrofluoroalkane (HFA) propellants can have smaller particle sizes (approximately 1 microm). Extrafine HFA aerosols have better access to the distal lung, with less oropharyngeal deposition. Imaging studies suggest that anti-inflammatory medication delivered as an extrafine aerosol produces beneficial changes in distal lung function. In one study, an HFA formulation of an inhaled corticosteroid reduced air trapping to a greater degree than a CFC formulation of the same corticosteroid. By extending the delivery of anti-inflammatory medication to the distal lung, the new HFA-based corticosteroids have the potential to treat asthma more effectively and at reduced steroid doses.

Effects of asthma and asthma therapies on bone mineral density

With improvements in techniques for measuring bone mass, interest and concern have increased about the effects of asthma therapies, particularly corticosteroids, on bone mineral density. Whether asthma itself causes bone loss remains unclear. Studies evaluating the effect of asthma therapies on bone mineral density are often difficult to interpret because of methodologic problems. These studies show that oral corticosteroids are associated with a reduction in bone mineral density and an increased risk of fracture. Studies evaluating the effects of inhaled corticosteroids on bone mineral density provide conflicting data, but there is increasing evidence that inhaled corticosteroids may have an adverse effect on bone. However, the benefits of inhaled corticosteroids in the treatment of asthma remain far greater than the risks. The data for the effects of other asthma therapies on bone mineral density are limited.

Side effects of corticosteroid therapy

BACKGROUND

Corticosteroids have been used for the treatment of inflammatory bowel disease since the late 1940s. Upwards of 80% of patients may respond acutely to treatment with these medications, although 20% or more may be refractory and others become dependent on corticosteroid use to suppress disease activity. Side effects in the acute situation are relatively minor, although significant side effects (e.g., psychosis) have been encountered; the long-term use of corticosteroids is more problematic. This creates a milieu for the potential for serious and irreversible problems. These side effects are discussed in detail. The side effects from corticosteroids emulate from exogenous hypercortisolism, which is similar to the clinical syndrome of Cushing's disease.

STUDY

PubMed search for years 1966-2000, author's personal manuscript/abstract files, and citations of known references.

CONCLUSION

Short-term corticosteroid use is associated with generally mild side effects, including cutaneous effects, electrolyte abnormalities, hypertension, hyperglycemia, pancreatitis, hematologic, immunologic, and neuropsychologic effects, although occasionally, clinically significant side effects may occur. Long-term corticosteroid use may be associated with more serious sequel, including osteoporosis, aseptic joint necrosis, adrenal insufficiency, gastrointestinal, hepatic, and ophthalmologic effects, hyperlipidemia, growth suppression, and possible congenital malformations.

Features of asthma in the elderly

Asthma has been considered a rare disease in the elderly, but recent studies have shown that it is as common in the elderly as in the middle-aged population. Diagnosis of asthma is often overlooked in older patients, leading to undertreatment. Spirometry, determination of expiratory flow lability, and histamine challenge tests are tools that are as usefulfor the evaluation of elderly asthmatics as they areforyoungerpatients. Asthma is more severe in the elderly, especially in long-standing asthmatics. Treatment of asthma in the elderly should follow the same stepwise guidelines that are recommended for all age groups, though it will require more intense monitoring. An aggressive treatment approach to mild and moderate asthma in young people is the best hope of changing the future trends of asthma in the elderly.

Chronic glucocorticoid therapy-induced osteoporosis in patients with obstructive lung disease

Long-term glucocorticoid (GC) therapy has been instrumental in decreasing morbidity and mortality in a variety of chronic inflammatory diseases, including persistent asthma. Long-term GC therapy is also widely prescribed for COPD. One of the important and often unrecognized side effects of chronic GC therapy is secondary osteoporosis. The risk of GC-induced bone loss is roughly correlated with daily dose, duration, and total cumulative lifetime dose of GC treatment. Oral prednisone increases the risk of bone loss and fracture. High doses of inhaled GCs may also increase the risk of osteopenia/osteoporosis, but the risk appears to be less than that associated with oral GCs. Hormone replacement therapy, oral and parenteral bisphosphonates, supplemental calcium and vitamin D, calcitonin, and fluoride compounds have been used, experimentally, in the management of GC-induced bone loss. Asthma and COPD specialists are key prescribers of oral and inhaled steroids and are likely to encounter patients with significant bone loss. Despite known risk factors and the availability of reliable diagnostic tools to recognize bone loss, the opportunity to slow, reverse, and treat bone loss is often missed. We present a review of the current literature regarding the incidence, treatment, and prevention of osteopenia/osteoporosis secondary to chronic GC therapy in adult asthma and COPD patients. Guidelines are presented regarding the identification of patients at risk for developing GC-induced secondary bone loss, and therapeutic alternatives are discussed.

Bones and Crohn's: problems and solutions

Inflammatory bowel disease may manifest in various extra intestinal manifestations. Osteopenia and various arthropathies may be debilitating. These may be related to the disease itself, patient genetics, lifestyle, or disease treatment. Calcium and vitamin D malabsorption, vitamin K deficiency, malnutrition, corticosteroid and other immunosuppressive medications, smoking, lack of exercise and postmenopausal state may all play important roles. Treatment may be undertaken to correct nutrient deficiencies, inhibit bone resorption and increase bone formation.

Asthma and chronic obstructive airway diseases are associated with osteoporosis and fractures: a literature review

The objective was to assess the association between asthma and/or chronic obstructive airway diseases (COAD), and osteoporosis, and appraise treatments of osteoporosis in these patients. MEDLINE and Excerpta Medica were searched for original research with control groups which tested the above association. One cohort and nine cross-section studies of bone density in patients with asthma and/or COAD were retrieved. These demonstrated clinically important bone density reductions of up to 29% in subjects, dependent upon daily oral corticosteroids, by a variety of measurement techniques, at various bone sites. Bone density reduction has also been less consistently reported in the absence of oral corticosteroids, suggesting that other factors including high-dose inhaled corticosteroids may have a role. Fracture studies. Three studies in oral corticosteroid-dependent asthmatics demonstrated a vertebral fracture prevalence up to 56%, and annual vertebral fracture incidence of up to 42%. The strength of the available evidence is limited, but suggests that patients with asthma and/or COAD are at increased risk of osteoporosis. The evidence of the association between osteoporosis and inhaled corticosteroids is much more limited than for oral corticosteroids. Bisphosphonates are promising agents to maintain and/or promote bone mass in this patient group.