Lesley C. McFarlane

Effects of repeated once daily dosing of three intranasal corticosteroids on basal and dynamic measures of hypothalamic-pituitary-adrenal–axis activity

BACKGROUND Intranasal corticosteroids are regarded as the first-line treatment for allergic rhinitis, but few studies have directly compared their systemic effects. OBJECTIVE We sought to compare the hypothalamic-pituitary-adrenal (HPA)-axis suppression with three intranasal corticosteroids in terms of basal and dynamic adrenocortical activity. METHODS Sixteen healthy volunteers (mean age, 30.7 years) were studied in a single-blind, randomized, four-way crossover study comparing placebo with 200 microg/day fluticasone propionate (FP), 220 microg/day triamcinolone acetonide (TAA), and 336 microg/day beclomethasone dipropionate (BDP). After 4 days of treatment, an overnight urine collection was taken for cortisol and creatinine excretion starting at 10 PM (14 hours after the fourth dose), and blood was taken for serum cortisol at 8 AM (24 hours after the fourth dose) and after stimulation with adrenocorticotrophic hormone (ACTH) (0.5 microg). RESULTS For overnight urinary cortisol excretion compared with placebo (20.8 nmol), there was a significant (p < 0.05) degree of suppression with FP (11.8 nmol) but not with TAA (16.0 nmol) or BDP (16.5 nmol). In terms of fold difference (95% CI for difference) from placebo, this amounted to 1.75-fold (1.01 to 3.03) for FP (43% suppression), 1.30-fold (0.75 to 2.25) for TAA (23% suppression), and 1.26-fold (0.73 to 2.18) for BDP (21% suppression). There was also a trend towards suppression of overnight urinary cortisol/creatinine excretion, but this was not statistically significant (placebo, 5.2 nmol/mmol; TAA, 5.0 nmol/mmol; BDP, 4.3 nmol/mmol; and FP, 4.3 nmol/mmol). Values for serum cortisol before and after ACTH stimulation showed no significant suppression. CONCLUSION Suppression of overnight urinary cortisol occurred with intranasal FP (43%), TAA (23%), and BDP (21%), although this was only statistically significant with FP. None of the drugs were associated with blunting of the response to ACTH stimulation. Further studies are indicated to establish whether the systemic effects of inhaled and intranasal corticosteroids are additive.

Effects of intranasal corticosteroids on adrenal, bone, and blood markers of systemic activity in allergic rhinitis

BACKGROUND Intranasal corticosteroids are regarded as the first-line treatment for allergic rhinitis, but few studies have directly compared their systemic effects. OBJECTIVE The purpose of this study was to compare the systemic bioactivity of aqueous formulations of intranasal budesonide, mometasone furoate (MF), and triamcinolone acetonide (TAA) in terms of adrenal, bone, and white blood cell markers. METHODS Twenty patients with allergic rhinitis, mean age (SE) 35.7 (3.5) years were studied in a single-blind, randomized, 4-way crossover design, with treatments separated by 7-day washout periods, comparing placebo with budesonide 200 micro(g) once daily, MF 200 micro(g) once daily, and TAA 220 micro(g) once daily. After 5 days of treatment at steady-state, serial blood and urine samples were taken for 24 hours. Collective and fractionated measurements (daytime, overnight, and 8 AM) were done on plasma cortisol and urine cortisol/creatinine excretion. Plasma osteocalcin and blood eosinophil counts were measured at 8 AM. RESULTS There was no significant difference between placebo and the active treatments with any of the markers of adrenal suppression. Mean values (SE) for 24-hour area under the curve plasma cortisol (nmol/L.hr) were placebo, 6312.9 (564.4); budesonide, 5908.8 (496.8); MF, 6374.1 (509.9); and TAA, 6239.2 (552.0). Twenty-four hour urinary cortisol/creatinine ratio (nanomoles per millimoles) showed placebo, 9.2 (0.5); budesonide, 8.5 (0.5); MF, 8.6 (0.4); and TAA, 8.6 (0.4). The diurnal circadian rhythm was unaffected, and there were only occasional patients with abnormally low cortisol values. There was also no suppression in terms of osteocalcin (placebo, 1.27 nmolL; budesonide, 1.22 nmol/L; MF, 1.33 nmol/L; and TAA, 1.24 nmol/L) and blood eosinophil count (placebo, 0.29 x 10(9)/L; budesonide, 0.27 x 10(9)/L; MF, 0.25 x 10(9)/L; and TAA, 0.24 x 10(9)/L). CONCLUSION Neither budesonide, MF, nor TAA produced significant systemic suppression of adrenal, bone, or white blood cell markers at the doses studied. This reflects the good safety profile of these aqueous intranasal formulations when taken at clinically recommended doses.

Effects of low dose fluticasone/salmeterol combination on surrogate inflammatory markers in moderate persistent asthma

Background: Noninvasive surrogate markers provide valuable information on the asthmatic inflammatory process. We wished to examine the effects of low dose fluticasone/salmeterol combination on different commonly used inflammatory markers in moderate persistent asthma.

Concomitant inhaled corticosteroid resensitises cardiac β2-adrenoceptors in the presence of long-acting β2-agonist therapy

AbstractObjective: The aim of the present study was to evaluate the effects of concomitant inhaled corticosteroid therapy on the sensitivity of cardiac β2-adrenoceptors in patients receiving regular long-acting β2-agonists. Methods: Twelve healthy subjects (6 female), mean age 29 years, were randomised in a double-blind cross-over study to receive either inhaled placebo or inhaled budesonide 1.2 mg twice daily, each for 7 days, with a minimum of 7 days washout period between the two treatments. Patients also received concomitant treatment with inhaled eformoterol 24 μg twice daily during each of the 2 treatment periods. The patients attended the laboratory during both treatment periods at 0730 hours, when a dose-response curve for systemic β2-adrenoceptor responses to inhaled salbutamol (0.8–3.2 mg) was constructed before and after completing 7 days of each treatment. Early morning (0800 hours) plasma cortisol was also evaluated as a marker of systemic glucocorticoid activity. Results: There was a significant fall in 0800 hours plasma cortisol induced by budesonide comparing pre- and post- values (407 vs 322 nmol · l−1, but not with placebo. There were no differences in the response to salbutamol prior to treatment when comparing eformoterol with placebo versus eformoterol with budesonide. Comparing before and after within-treatment heart rate response, there was a significant reduction in peak salbutamol response with eformoterol and placebo, which was partially reversed by eformoterol and budesonide. For between-treatment comparisons after eformoterol treatment, the heart rate was significantly higher in the presence of budesonide in comparison with placebo for peak salbutamol response (change from baseline), i.e. 24.2 vs 34.7 beats · min−1. There was, however, no significant difference in the peak delta potassium response to salbutamol after eformoterol treatment when comparing budesonide with placebo (−0.39 vs −0.48 mmol · l−1). Conclusion: Concomitant therapy with inhaled budesonide resensitised the cardiac β2-adrenoceptor response to salbutamol in subjects who were receiving regular twice-daily eformoterol. This may be of clinical relevance in terms of the propensity for systemic β2-mediated adverse effects with repeated puffs of salbutamol, which might conceivably occur in the setting of acute asthma.

Effects of high-dose inhaled fluticasone propionate on the hypothalamic-pituitary- adrenal axis in asthmatic patients with severely impaired lung function

BACKGROUND The effects of high-dose fluticasone propionate therapy on dynamic cortisol stimulation in severe asthma are unknown. OBJECTIVE To evaluate the human corticotropin-releasing factor (hCRF)-stimulated plasma cortisol response to fluticasone propionate therapy in severe asthmatic patients with impaired airway caliber (forced expiratory volume in 1 second [FEV1] < 60% of predicted) and in control subjects. METHODS Ten severe asthmatic patients (mean FEV1, 47% of predicted) and 10 controls (mean FEV1, 104% of predicted) received fluticasone propionate, 2,000 microg/d, via a 750-mL primed spacer for 2 weeks. Plasma cortisol levels before and after hCRF stimulation and overnight 10-hour urinary cortisol excretion corrected for creatinine concentration (OUCC) were measured at baseline after washout and 12 hours after the last dose of fluticasone propionate. RESULTS Baseline values before fluticasone propionate use were not significantly different in asthmatic patients vs controls for plasma cortisol before and after hCRF stimulation and OUCC. Comparing values at baseline vs after fluticasone propionate use, there was no significant suppression of plasma cortisol levels before (378.2 vs 357.4 nmol/L) or after (510.5 vs 507.9 nmol/L) hCRF stimulation or OUCC (8.2 vs 7.5 nmoL/mmoL) in asthmatic patients. In controls, all outcomes were significantly suppressed comparing values before vs after fluticasone propionate therapy: plasma cortisol levels before (423.5 vs 200.2 nmol/L; P = .002) and after (503.5 vs 291.1 nmol/L; P = .001) hCRF stimulation and OUCC (6.5 vs 2.4 nmol/mmol; P = .002). CONCLUSION Patients with severe persistent asthma and impaired airway caliber seem to be protected from developing systemic adverse effects with high-dose fluticasone propionate therapy, as evaluated by basal and dynamic measures of hypothalamic-pituitary-adrenal axis activity.

Adrenocortical activity with repeated administration of one-daily inhaled fluticasone propionate and budesonide in asthmatic adults

AbstractObjective: The aim of this study was to evaluate the steady-state effects of once-daily inhaled fluticasone propionate (FP) and budesonide (BUD) on adrenocortical activity in asthmatic patients. Methods: Ten asthmatic patients with a mean age of 31.2 years, a mean forced expiratory volume in 1 s (FEV1) of 91% predicted and a forced mid-expiratory flow (FEF25–75) of 62.3% predicted were studied in a single-blind randomised crossover design comparing placebo (PL), FP (375 μg per day and 750 μg per day) and BUD (400 μg per day and 800 μg per day) all given once daily for 4 days at each dose via a pressurised metered dose inhaler (pMDI) at 0800 hours. After 4 days of treatment, plasma cortisol was measured at 0800 hours (24 h after the last dose) and a 10-h overnight urine collection was taken, 14 h after the last dose (2200–0800 hours) for analysis of cortisol and creatinine excretion. Results: Plasma cortisol levels (nmol · l−1, as geometric mean) at 0800 hours demonstrated a significant difference between the highest doses of FP and BUD (424.1 vs 510.3 nmol · l−1, respectively) but not between the low doses (506.8 vs 514.9 nmol · l−1; PL 532.2 nmol · l−1). For the highest dose FP (750 μg) this equated to 20% suppression of 0800 hours plasma cortisol. Likewise, for overnight urinary cortisol output (nmol · 10 h−1, as geometric mean), there was a significant difference at the high doses of FP and BUD (25.5 vs 38.2 nmol · 10 h−1), but not at the low doses 31.3 vs 34.8 nmol · 10 h−1; PL 32.0 nmol · 10 h−1. For the overnight urinary cortisol/creatinine ratio (nmol · mmol−1, as geometric mean) there was a similar trend; 4.5 vs 6.1 nmol · mmol−1 for high dose and 5.6 vs 6.3 nmol · mmol−1 for low dose; PL 5.9 nmol · mmol−1. Conclusion: Repeated doses of FP 750 μg once daily caused greater adrenal suppression than BUD 800 μg once daily, when comparing effects on plasma cortisol levels at 0800 hours, 24 h after the last dose, as well as effects on overnight urinary cortisol output. Neither FP 375 μg once daily nor BUD 400 μg once daily produced detectable adrenal suppression.

Adrenal suppression with high doses of inhaled fluticasone propionate and triamcinolone acetonide in healthy volunteers.

AbstractStudy objective: This study was conducted to compare the adrenal suppression of inhaled fluticasone propionate and triamcinolone acetonide in healthy volunteers, both given via their respective pressurised metered dose inhaler (pMDI) devices at high doses within the manufacturers recommended dose range. Design: We used a single (investigator) blind, randomised, crossover design comparing a total daily dose of 1.625 mg fluticasone propionate delivered via a pMDI, 1.60 mg daily of triamcinolone acetonide delivered via a pMDI with integrated spacer, or placebo pMDI; each drug was given in two divided doses at 0800 hours and 2200 hours over a 24-h period. Each drug treatment was separated by a 1-week washout. Patients: Twelve normal subjects mean age 27.5 years were studied. Measurements: Blood samples were taken for 0800 hours plasma cortisol, i.e. 10 h following the second dose. Ten hour urine collections (2200 hours until 0800 hours) were taken for urinary cortisol and creatinine excretion. Results: For the 0800 hours plasma cortisol (geometric mean, nmol · l−1) compared with placebo (353) fluticasone propionate (138) produced significant (P<0.05) suppression (2.57-fold difference), whereas triamcinolone acetonide (263) did not (1.34-fold difference). Fluticasone propionate produced a 1.91-fold greater adrenal suppression than triamcinolone acetonide (95% CI 1.10 to 3.33). Individual subjects with abnormally low 0800 hours cortisol values <150 nmol · l−1 (<5.4 μg/dl) were n=4 for fluticasone propionate and n=0 for triamcinolone acetonide. Overnight urinary cortisol/creatinine ratio (geometric mean, nmol/mmol) did not show any difference between fluticasone propionate (1.48) and triamcinolone acetonide (1.60), with both producing significant suppression versus placebo (4.01): triamcinolone acetonide 2.50-fold difference (95% CI 1.45–4.24); fluticasone propionate 2.71-fold difference (95% CI 1.57–4.69). Conclusion: Fluticasone propionate 1.625 mg/day (pMDI) produced an approximately two-fold greater adrenal suppression of 0800 hours plasma cortisol than triamcinolone acetonide 1.60 mg per day (Oral Inhaler) when given twice daily, and one third of subjects with fluticasone had abnormally low 0800 hours cortisol values <150 nmol · l−1 (<5.4 μg · dl−1). There were no differences between the drugs for urinary cortisol excretion. Further dose-ranging studies are required at steady-state in asthmatic subjects in order to see whether differences occur at lower doses on the steep part of the dose–response curve for both plasma and urinary cortisol suppression.

Acute neurohormonal responses to hypoxaemia in man.

We have studied the integrated neuroendocrine and haemodynamic effects of acute hypoxaemia in ten healthy volunteers studied on two separate occasions. After reaching a resting haemodynamic state, subjects breathed either room air or a nitrogen/oxygen mixture which rendered arterial oxygen saturation between 75% and 80%. Measurements of pulmonary and systemic haemodynamics were made and blood samples taken at baseline and after 30 min breathing air or the hypoxic gas. Blood was assayed for plasma sodium and potassium, renin-angiotensin-aldosterone system activity, natriuretic peptides, cortisol and catecholamines. Hypoxaemia significantly increased heart rate, cardiac output and mean pulmonary artery pressure (Ppa), but not mean arterial pressure compared with normoxaemia. Although plasma renin activity, angiotensin II and cortisol were unaffected by hypoxaemia, plasma aldosterone fell significantly in comparison with normoxaemia. This was associated with an increase in plasma atrial natriuretic peptide (ANP) but not b-type natriuretic peptide (BNP) during hypoxaemia whilst no changes were observed during normoxaemia. The increase in plasma ANP correlated positively with the increase inPpa. During hypoxaemia there is therefore dissociation of the renin-angiotensin-aldosterone system where plasma aldosterone decreased, despite there being no effects on plasma renin activity and angiotensin II or on plasma cortisol. This dissociation may be due to increased levels of ANP but not BNP having specific inhibitory effects on aldosterone biosynthesis. ANP increased in proportion to the degree of pulmonary vasoconstriction induced by hypoxaemia which may indicate a counter-regulatory role.

Respirable dose delivery of fluticasone propionate from a small valved holding chamber, a compact breath actuated integrated vortex device and a metered dose inhaler

AIMS To compare the respirable dose delivery of the hydrofluroalkane fluticasone propionate (HFA-FP) via an optimally prepared Aerochamber Plus spacer (AP), via a Synchro-Breathe (SB) device, and pMDI Evohaler (EH). METHODS Seventeen mild to moderate asthmatics completed the study using a randomized, double-blind, double-dummy, three way crossover design. Single doses of placebo or HFA-FP 2.0 mg were administered via the EH, AP, and SB devices. The overnight urinary cortisol : creatinine ratio (OUCC) was measured at baseline and after each dose. RESULTS Significant suppression of OUCC occurred from baseline with AP and SB but not EH devices (geometric mean fold suppression, 95% CI): AP: 3.18 (2.29, 4.36), P < 0.001; SB: 1.79 (1.31, 2.40), P = 0.001; EH: 1.12 (0.69, 1.44), p = 0.37 (equating to 68%, 45% and 9% falls, respectively). Significant differences in OUCC between devices were as follows: (geometric mean fold difference, 95% CI): AP vs. EH. 2.83 (2.09, 3.82), P < 0.001; AP vs. SB: 1.78 fold (1.21, 2.60), P = 0.003; SB vs. EH: 1.59 (1.09, 2.31), P = 0.013 (equating to 65%, 44% and 37% differences, respectively). CONCLUSIONS The use of an optimally prepared AP spacer and breath actuated SB device, when compared with pMDI, significantly increased the respirable dose of HFA-FP.

Differential anti-inflammatory effects of large and small particle size inhaled corticosteroids in asthma.

Background:  Extra‐fine particle formulations of hydrofluoroalkane‐134a beclometasone dipropionate (HFA‐BDP) exhibit clinical effects comparable with conventional particle formulations of chlorofluorocarbon beclometasone dipropionate (CFC‐BDP) at half the dose. There is little data comparing their effects on inflammation. We have evaluated the effects of HFA‐BDP and CFC‐BDP on pulmonary and systemic markers of asthmatic inflammation.