Effect of inhaled corticosteroids on bronchial responsiveness in patients with "corticosteroid naive" mild asthma: a meta-analysis

BACKGROUND: Inhaled corticosteroids are the most efficacious anti-inflammatory drugs in asthma. International guidelines also advocate the early introduction of inhaled corticosteroids in corticosteroid naive patients. A study was undertaken to assess the effects of inhaled corticosteroids on bronchial hyperresponsiveness in patients with corticosteroid naive asthma by conventional meta-analysis. METHODS: A Medline search of papers published between January 1966 and June 1998 was performed and 11 papers were selected in which the patients had no history of treatment with inhaled or oral corticosteroids. Bronchial responsiveness to bronchoconstricting agents was considered as the main outcome parameter. Doubling doses (DD) of histamine or methacholine were calculated. RESULTS: The total effect size of inhaled corticosteroids (average daily dose 1000 microg) versus placebo in the 11 studies was +1.16 DD (95% confidence interval (CI) +0.76 to +1.57). When only the eight short term studies (2-8 weeks) were analysed the effect size of the bronchoconstricting agent was +0.91 DD (95% CI +0.65 to +1.16). No relationship was found between the dose of inhaled corticosteroid used and the effect on bronchial responsiveness. CONCLUSION: This meta-analysis in patients with corticosteroid naive asthma indicates that, on average, high doses of inhaled corticosteroids decrease bronchial hyperresponsiveness in 2-8 weeks. It remains unclear whether there is a dose-response relationship between inhaled corticosteroids and effect on bronchial hyperresponsiveness.     

Moderate dose inhaled corticosteroids plus salmeterol versus higher doses of inhaled corticosteroids in symptomatic asthma

BACKGROUND: There is uncertainty as to the dose of inhaled corticosteroids (ICS) at which to start concomitant long acting beta agonist (LABA) treatment in patients with asthma not adequately controlled by ICS alone. METHODS: A meta-analysis was carried out of randomised, double blind clinical trials that compared the efficacy of adding salmeterol to moderate doses of ICS (fluticasone propionate 200 mug/day or equivalent) with increasing the ICS dose by at least twofold in symptomatic adult patients with asthma. The main outcome measures were the number of subjects withdrawn from the study due to asthma and the number of subjects with at least one moderate or severe exacerbation. RESULTS: Twelve studies with a total of 4576 subjects met the inclusion criteria for the analyses. The number of subjects withdrawn due to asthma and with at least one moderate or severe exacerbation was higher in the high dose ICS group (odds ratios 1.58, 95% CI 1.12 to 2.24 and 1.35, 95% CI 1.10 to 1.66, respectively). For the secondary outcome variables (forced expiratory volume in 1 second, morning and evening peak expiratory flow, and daytime beta agonist use) there was significantly greater benefit in the salmeterol group. CONCLUSIONS: This meta-analysis shows that the addition of salmeterol to moderate doses of ICS (fluticasone 200 mug/day or equivalent) in patients with asthma symptomatic at that dose results in significantly greater clinical benefit than increasing the dose of ICS by twofold or more.     

Use of sequential quadrupling dose regimens to study efficacy of inhaled corticosteroids in asthma

BACKGROUND: Inhaled corticosteroids are widely used to treat asthma. There is a need to be able to compare different inhaled corticosteroids and different doses of an inhaled corticosteroid to determine potency and dose equivalence, but measuring efficacy in a dose related manner is difficult because of their slow onset of action. There is uncertainty about the role of sequential dosing regimens and the best end point for such studies. We have explored the use of sequential quadrupling dose regimens and a range of end points to assess the response to budesonide in subjects with asthma. METHODS: 21 subjects with mild asthma, aged 18-65, took part in a randomised three way crossover study comparing two sequential and one non-sequential regimen, separated by at least 3 weeks. The sequential regimens consisted of increasing doses of inhaled budesonide (100, 400 1600 microg/day) with each dose being given for 1 or 2 weeks; the non-sequential regimen consisted of 1600 microg/day for 2 weeks with end points measured after 1 and 2 weeks. The end points studied included the provocative dose of adenosine monophosphate causing a 20% fall in forced expiratory volume in 1 second (PD20AMP), lung function, symptoms, and bronchodilator use. RESULTS: There was a dose related increase in PD20AMP with both sequential dose regimens. The increase in PD20AMP ranged from 1.49 doubling doses (DD) following the lowest dose (100 microg/day) to 3.1 DD following the highest dose (1600 microg/day) in the 1 week sequential regimen and from 1.98 to 4.03 DD in the 2 week sequential regimen; standard deviations (SD) for the changes in PD20AMP ranged from 1.3 to 2.6 DD. Changes in forced expiratory volume in 1 second (FEV1) and morning peak expiratory flow rate (PEFR) were dose related but small and more variable (maximum change in FEV1=148 ml, SD 228 ml), while changes in evening PEFR, symptoms, and bronchodilator use were small and not dose related. Change in PD20AMP after budesonide 1600 microg did not differ significantly between regimens. CONCLUSION: Combining PD20AMP measurements with a sequential regimen of three quadrupling doses of an inhaled corticosteroid given for 1 or 2 weeks provides clear dose-response curves for comparative studies. PD20AMP is a more sensitive end point for this purpose than FEV1, PEFR, symptoms, or relief inhaler use.     

Use of inhaled corticosteroids and risk of fractures.

Treatment with systemic corticosteroids is known to increase the risk of fractures but little is known of the fracture risks associated with inhaled corticosteroids. A retrospective cohort study was conducted using a large UK primary care database (the General Practice Research Database [GPRD]). Inhaled corticosteroid users aged 18 years or older were compared with matched control patients and to a group of noncorticosteroid bronchodilator users. Patients with concomitant use of systemic corticosteroids were excluded. The study comprised 170,818 inhaled corticosteroid users, 108,786 bronchodilator users, and 170,818 control patients. The average age was 45.1 years in the inhaled corticosteroid, 49.3 years in the bronchodilator, and 45.2 years in the control groups. In the inhaled corticosteroid cohort, 54.5% were female. The relative rates (RRs) of nonvertebral, hip, and vertebral fractures during inhaled corticosteroid treatment compared with control were 1.15 (95% CI, 1.10-1.20), 1.22 (95% CI, 1.04-1.43), and 1.51 (95% CI, 1.22-1.85), respectively. No differences were found between the inhaled corticosteroid and bronchodilator groups (nonvertebral fracture RR = 1.00; 95% CI, 0.94-1.06). The rates of nonvertebral fractures among users of budesonide (RR = 0.95; 95% CI, 0.85-1.07) and fluticasone propionate (RR = 1.03; 95% CI, 0.71-1.49) were similar to the rate determined for users of beclomethasone dipropionate. We conclude that users of inhaled corticosteroids have an increased risk of fracture, particularly at the hip and spine. However, this excess risk may be related more to the underlying respiratory disease than to inhaled corticosteroid.     

哮喘患者感知控制力对糖皮质激素吸入治疗依从性的影响

目的探讨哮喘患者感知控制力对吸入糖皮质激素治疗依从性的影响,为提高患者糖皮质激素治疗依从性提供参考。方法采用方便抽样方法,选取哮喘患者,采用一般资料问卷、哮喘感知控制力问卷(PCAQ)、支气管哮喘用药依从性量表(MARS-A)进行调查。结果 118例患者的感知控制力总分为33.04±4.57;39.83%的患者吸入糖皮质激素治疗依从性好,60.17%的患者吸入糖皮质激素治疗依从性差;ICS治疗依从性与心理控制源、自我效能感呈正相关(r=0.678、0.653,均P0.01),与习得无助感呈负相关(r=-0.636,P0.01);文化程度、家族史、自我效能感、心理控制源和习得无助感是ICS治疗依从性的影响因素(均P0.01)。结论哮喘患者感知控制力水平低可影响糖皮质激素治疗依从性,提高哮喘患者感知控制力水平,恢复其对生活和疾病的控制,可以更好地提高哮喘患者ICS治疗的依从性。     

Bone mineral density in subjects with mild asthma randomised to treatment with inhaled corticosteroids or non-corticosteroid treatment for two years

BACKGROUND: Inhaled corticosteroids are clearly beneficial for patients with asthma of moderate severity, but the risks and benefits of using them in patients with milder asthma are less clear. We have compared the change in bone mineral density over 2 years in adults with mild asthma randomised to receive an inhaled corticosteroid or non-corticosteroid treatment. METHODS: Subjects with mild asthma (mean forced expiratory volume in one second (FEV(1)) 86% predicted, mean age 35 years, taking beta agonists only) were randomised to receive inhaled budesonide, inhaled beclomethasone dipropionate, or non-corticosteroid treatment for 2 years in a prospective randomised open study in 19 centres in France, New Zealand, Spain, and the UK. The corticosteroid dose was adjusted according to a written self-management plan. The main outcome measure-change in bone mineral density after 6, 12, and 24 months-was measured "blind". Secondary outcomes included lung function, the relation between change in bone density and inhaled steroid dose and change in biochemical markers of bone metabolism. RESULTS: Of 374 subjects randomised, 239 (64%) completed the study and were included in the analysis. The median daily doses of inhaled budesonide (n=87) and beclomethasone (n=74) were 389 microg and 499 microg, respectively. Subjects treated with an inhaled corticosteroid had better asthma control than those in the reference group (n=78). Change in bone mineral density did not differ between the three groups over the 2 years, nor did it correlate with changes in markers of bone metabolism. The mean change in bone mineral density over 2 years in the budesonide, beclomethasone dipropionate, and reference groups was 0.1%, -0.4%, and 0.4% for the lumbar spine and -0.9%, -0.9%, and -0.4% for neck of the femur. Mean daily dose of inhaled steroid was related to reduction in bone mineral density at the lumbar spine but not at the femoral neck. CONCLUSION: In subjects with mild asthma an inhaled corticosteroid provided better asthma control than alternative non-corticosteroid treatment with no difference in change in bone mineral density over 2 years. The relation between dose of inhaled corticosteroid and change in bone density at the lumbar spine may be due to a direct effect of inhaled corticosteroids on bone. Since inhaled steroid dose is also related inversely to lung function, an effect of asthma severity on bone density was also possible.     

Effects of inhaled tumour necrosis factor alpha in subjects with mild asthma

BACKGROUND: Inhaled tumour necrosis factor alpha (TNF alpha) has previously been shown to induce airway neutrophilia and increased airway reactivity in normal subjects. It was hypothesised that a similar challenge would increase airway reactivity in those with mild asthma, but that the inflammatory profile may differ. METHODS: Ten mild asthmatic subjects were recruited on the basis of clinical asthma and either a sensitivity to methacholine within the range defined for asthma or a 20% improvement in forced expiratory volume (FEV(1)) after 200 micro g salbutamol. Subjects inhaled either vehicle control or 60 ng recombinant human (rh)TNF alpha and were studied at baseline, 6, 24, and 48 hours later. Variables included spirometric parameters, methacholine provocative concentration causing a 20% fall in FEV(1) (PC(20)), induced sputum differential cell count, relative sputum level of mRNA of interleukins (IL)-4, IL-5, IL-9, IL-14, IL-15 and TNF alpha, and the exhaled gaseous markers of inflammation, nitric oxide and carbon monoxide. RESULTS: PC(20) showed an increase in sensitivity after TNF alpha compared with control (p<0.01). The mean percentage of neutrophils increased at 24-48 hours (24 hour control: 1.1 (95% CI 0.4 to 2.7) v 9.2 (95% CI 3.5 to 14.9), p<0.05), and there was also a rise in eosinophils (p=0.05). Relative levels of sputum mRNA suggested a rise in expression of TNF alpha, IL-14, and IL-15, but no change in IL-4 and IL-5. Spirometric parameters and exhaled gases showed no significant change. CONCLUSION: The increase in airway responsiveness and sputum inflammatory cell influx in response to rhTNF alpha indicates that TNF alpha may contribute to the airway inflammation that characterises asthma.     

Effects of high doses of inhaled corticosteroids on adrenal function in children with severe persistent asthma.

BACKGROUND--Childhood asthma generally responds well to inhaled corticosteroids within the dosage range recommended by the manufacturers, but it is sometimes necessary to use higher doses--that is, above 400 micrograms/day--a practice which has become more widespread recently. Whereas the lack of adrenal suppression in children given inhaled corticosteroids in normal doses is well documented, little is known about the effects of higher doses. METHODS--The effects on adrenal function of high dose (above 400 micrograms/day) inhaled corticosteroids were evaluated by measuring cortisol concentration in the morning and performing a short tetracosactrin test in 49 children taking budesonide (mean age 9.2 years (range 4 to 16 years) and 28 children taking beclomethasone dipropionate (10.2 years (5 to 13 years)). Twenty three non-asthmatic children (8.9 years (4.9 to 13 years)) who were under investigation for short stature served as controls for the study. RESULTS--Compared with controls mean basal cortisol concentration was lower in children taking budesonide and beclomethasone dipropionate (control 401 (26.8) nmol/l, budesonide 284 (22) nmol/l, beclomethasone dipropionate 279 (23.2) nmol/l). Sixteen of the 49 children taking budesonide had subnormal basal cortisol concentrations compared with seven of the 28 taking beclomethasone dipropionate. Mean stimulated cortisol concentrations were lower in children taking inhaled corticosteroids than in controls, with no difference between those taking budesonide or beclomethasone dipropionate. CONCLUSIONS--Adrenal suppression occurs in some children who are given inhaled corticosteroids in doses greater than 400 micrograms/day. It may therefore be advisable to try alternative treatments before such doses are used.     

Effect of differing doses of inhaled budesonide on markers of airway inflammation in patients with mild asthma

BACKGROUND: It is desirable to prescribe the minimal effective dose of inhaled steroids to control asthma. To ensure that inflammation is suppressed whilst using the lowest possible dose, a sensitive and specific method for assessing airway inflammation is needed. METHODS: The usefulness of exhaled nitric oxide (NO), sputum eosinophils, and methacholine airway responsiveness (PC20) for monitoring airway inflammatory changes following four weeks of treatment with an inhaled corticosteroid (budesonide via Turbohaler) were compared. Mild stable steroid naive asthmatic subjects were randomised into two double blind, placebo controlled studies. The first was a parallel group study involving three groups receiving either 100 micrograms/day budesonide (n = 8), 400 micrograms/day budesonide (n = 7), or a matched placebo (n = 6). The second was a crossover study involving 10 subjects randomised to receive 1600 micrograms budesonide or placebo. The groups were matched with respect to age, PC20, baseline FEV1 (% predicted), exhaled NO, and sputum eosinophilia. RESULTS: There were significant improvements in FEV1 following 400 micrograms and 1600 micrograms budesonide (11.3% and 6.5%, respectively, p < 0.05). This was accompanied by significant reductions in eosinophil numbers in induced sputum (0.7 and 0.9 fold, p < 0.05). However, levels of exhaled NO were reduced following each budesonide dose while PC20 was improved only with 1600 micrograms budesonide. These results suggest that exhaled NO and PC20 may not reflect the control of airway inflammation as accurately as the number of eosinophils in sputum. There were dose dependent changes in exhaled NO, sputum eosinophils, and PC20 to inhaled budesonide but a plateau response of exhaled NO was found at a dose of 400 micrograms daily. CONCLUSION: Monitoring the number of eosinophils in induced sputum may be the most accurate guide to establish the minimum dose of inhaled steroids needed to control inflammation. This, however, requires further studies involving a larger number of patients.     

Initial starting dose of inhaled corticosteroids in adults with asthma: a systematic review

BACKGROUND: Asthma guidelines vary in their recommendations for the initial dose of inhaled corticosteroid (ICS) in asthma. A systematic review of the literature was conducted to establish the optimal starting dose of ICS for asthma in adults. METHODS: Randomised controlled trials comparing two doses of the same ICS in adults with asthma and no concomitant inhaled or oral corticosteroid were assessed. Included trials were analysed according to the following ICS dose comparisons: high (> or =800 microg/day beclomethasone (BDP)) versus moderate (400<800 microg/day BDP) (n = 7); moderate versus low (<400 microg/day BDP) (n = 6); step down versus constant dose (n = 4). RESULTS: Fourteen publications describing 13 trials were included in the review. Studies (n = 4) that compared a step down approach with a constant moderate/low dose of ICS found no difference in lung function, symptoms, or rescue medications between the two treatment approaches (p>0.05). There was no difference in the change in morning peak flow after treatment with high compared with moderate dose ICS. When compared with low dose ICS, moderate dose ICS significantly improved morning peak flow (change from baseline WMD 11.14 l/min, 95% CI 1.34 to 20.93) and nocturnal symptoms (SMD -0.29, 95% CI -0.53 to -0.06). CONCLUSIONS: For patients with asthma who require ICS, starting with a moderate dose is equivalent to starting with a high dose and stepping down. The small non-significant benefits of starting with a high ICS dose are not of sufficient clinical benefit to warrant its use. Initial moderate ICS doses appear to be more effective than an initial low ICS dose.     

Cross sectional investigation of the effects of inhaled corticosteroids on bone density and bone metabolism in patients with asthma

BACKGROUND: Bone mineral density has been reduced in patients with asthma taking inhaled corticosteroids in some cross sectional studies and this could be important if treatment is continued for several decades. The possibility of confounding by age, menopausal status, physical activity and, especially, past oral steroid use has not been excluded in most studies. The present study was designed to assess the magnitude of any reduction in bone mineral density in relation to inhaled steroid use after adjusting for these factors. METHODS: Bone mineral density (BMD), vertebral fractures, and markers of bone metabolism (serum osteocalcin, procollagen peptide I, bone-specific alkaline phosphatase, and urinary deoxypyridinoline cross links) were measured in 81 patients with asthma age 20-40 years; 34 patients (19 men) who had never had inhaled or systemic steroids and 47 (19 men) who had taken inhaled steroids for at least five years with limited exposure to systemic steroids in the past. Data relating to past medication use, physical activity, smoking, and other confounding factors were collected by questionnaire. The relation between inhaled steroid dose and duration and BMD was assessed by linear regression analysis, accounting for potential confounders including weight, exercise, and oral steroid use. RESULTS: The 47 patients taking an inhaled steroid had a mean current dose of 620 micrograms/day (range 100-3000 micrograms), a mean duration of use of 7.8 years, and had had a mean of 0.85 courses of prednisolone in the past. There was no significant difference in mean BMD values between those who were and those who were not on inhaled steroids in men or women. However, on multivariate analysis, cumulative inhaled steroid dose was associated with a reduction in posterior-anterior (P-A) and lateral lumbar spine bone mineral density in women, equivalent to a 0.11 standard deviation reduction in bone density per 1000 micrograms/day inhaled steroid per year after adjustment for potential confounding factors (95% CI for P-A spine 0.01 to 0.22; for lateral spine 0.02 to 0.21). Previous oral steroid use was not an important confounding factor in these patients. Inhaled steroid use was not related to BMD at the wrist or hip in women or at any skeletal site in men. Women taking an inhaled steroid had lower levels of serum osteocalcin than those not taking them, although this was not dose related. Inhaled steroid use was not associated with differences in other markers of bone metabolism in men or women or with the presence of vertebral fractures. CONCLUSIONS: Although an effect of confounding factors cannot be excluded entirely in a cross sectional study, our findings are in keeping with an effect of inhaled steroid therapy in reducing bone density in the spine in women and provide an estimate of the magnitude of this effect.


     

Lung function decline in asthma: association with inhaled corticosteroids, smoking and sex

BACKGROUND: Inhaled corticosteroids (ICS) provide short term benefits in asthma but the long term effects are still unknown. METHODS: 281 patients diagnosed with moderate to severe asthma in 1963-75 were re-examined in 1991-9. Information was collected on forced expiratory volume in 1 second (FEV(1)), bronchial hyperresponsiveness, atopy, smoking, use and dosage of oral and ICS. Patients were included in the analyses if they had at least three FEV(1) measurements during two consecutive years after the age of 30 and used ICS during follow up. RESULTS: Analyses were performed on 122 patients. During a median follow up period of 23 years, 71 men and 51 women had on average 37 and 40 individual FEV(1) measurements, respectively. Linear mixed effect models showed that men had a mean annual decline in FEV(1) of 20.6 ml/year less after ICS initiation than before (p = 0.011), and in women the decline in FEV(1) was 3.2 ml/year less (p = 0.73). In individuals with <5 pack years of smoking the decline in FEV(1) was 36.8 ml/year less after ICS institution in men (p = 0.0097) and 0.8 ml/year less in women (p = 0.94), the difference between the sexes being significant (p = 0.045). These effects were not observed in those with > or =5 pack years smoking. A higher daily dose of ICS was associated with a smaller decline in FEV(1) in men (p = 0.006), an effect not observed in women. CONCLUSION: Treatment with ICS in adult patients with moderate to severe asthma was associated with a reduction in the decline in FEV(1) over a 23 year follow up period in men who had smoked <5 pack years. This effect was dose dependent and was not present in women or in men with > or =5 pack years of smoking at follow up. The lack of effect of ICS on the decline in FEV(1) in women needs further study.     

Use of inhaled corticosteroids during the first trimester of pregnancy and the risk of congenital malformations among women with asthma

AIM: To investigate whether the maternal use of different doses of inhaled corticosteroids (ICSs) during the first trimester of pregnancy for the treatment of asthma increases the risk of congenital malformations in the offspring. METHODS: From the linkage of three administrative Canadian databases, a cohort of 4561 pregnancies from women with asthma who delivered between 1990 and 2000 was reconstructed. A two-stage sampling cohort design was used to acquire additional data from the woman's medical chart. Cases of congenital malformation were identified from the medical services database or the hospital database. Using refill patterns of medications, the average daily dose of ICSs used during the first trimester was calculated and categorised as follows: 0, 1-500, 500-1000 and >1000 microg/day in beclomethasone-chlorofluorocarbon equivalent. A Generalized Estimation Equation model was used to estimate the adjusted odds ratio of congenital malformation as a function of ICS daily dose. All analyses were performed for all malformations and major malformations separately. RESULTS: Within the cohort 418 babies were identified with a congenital malformation (9.2%), 278 of which had a major malformation. About 40% of women used ICSs during the first trimester, but only 5.3% of women used >500 microg/day. The adjusted odds ratio (95% CI) for all malformations associated with the use of ICSs during the first trimester was: 0.77 (0.53 to 1.13) for 1-500, 0.41 (0.19 to 0.92) for 501-1000 and 1.00 (0.42 to 2.36) for >1000 microg/day. The corresponding figures for major malformations were 0.90 (0.64 to 1.24), 0.56 (0.22 to 1.43) and 1.67 (0.56 to 5.03). CONCLUSION: This study adds evidence to the safety of ICSs for the treatment of asthma during pregnancy, with regard to the likelihood of congenital malformation.