Utility of single versus multiple breath washout in adult asthma.

Nitrogen multiple breath washout (N2 MBW) is a sensitive method to identify peripheral airway involvement in asthma, but is a time-consuming test. The N2 vital capacity single breath (VC SBW) test offers greater time efficiency, but concordance with N2 MBW is poorly understood. The prevalence of peripheral airway abnormality was determined by N2 MBW and N2 SBW tests in 194 asthmatic subjects aged 18-1 years. N2 MBW data were related to findings in 400 healthy controls, aged 17-71 years, while N2 SBW data were compared to findings in 224 healthy controls, aged 15-65 years, to derive equipment-specific reference values. Amongst asthmatic subjects, relationships between N2 SBW and N2 MBW outcomes were studied. N2 SBW relationship with clinical history, spirometry, blood eosinophils and fraction exhaled nitric oxide (FENO) data was also explored. The prevalence of peripheral airway involvement (i.e. abnormal ventilation distribution) determined by N2 SBW-derived phase III slope (N2 SIII ) was 24·7%, compared to 44% determined by N2 MBW-derived lung clearance index (LCI) (P<0·001). Predictors of abnormal N2 SIII were older age, smoking history and lower FEV1. N2 SBW offers lower sensitivity than N2 MBW to detect small airway dysfunction in adult asthma, but may be a marker of more severe disease.

Clinical characteristics of adult asthma associated with small airway dysfunction.

Suboptimal asthma control is common despite modern asthma therapy. The degree of peripheral airway involvement remains unclear and poor medication delivery to these regions might be a contributing reason for this failure in obtaining adequate symptom control. A cohort of 196 adults (median (range) age 44 (18-61) years, 109 females, 54 ex-smokers, six current smokers) with physician-diagnosed asthma were recruited from primary care. Subjects were characterized clinically by interviews, questionnaires, skin prick tests (SPT) and blood eosinophil counts. Lung function was assessed by spirometry, impulse oscillometry (IOS) and nitrogen multiple breath washout (N2 MBW). IOS assessed peripheral airway resistance (FDR, frequency dependence of resistance). N2 MBW assessed global ventilation inhomogeneity (LCI, lung clearance index), specific indices of peripheral airway function (Scond × VT and Sacin × VT; VT, tidal volume), and inter-regional inhomogeneity (specific ventilation ratio). Never-smoking healthy cohorts of 158 and 400 adult subjects provided local reference values for IOS and N2 MBW variables, respectively. Peripheral airway dysfunction was detected in 31% (FDR or specific ventilation ratio) to 47% (Scond x VT) of subjects. Risk factors for peripheral airway dysfunction were identified. Among subjects with low FEV1 and either positive smoking history and/or blood eosinophilia (>4.0%), 63% had abnormality across all peripheral airway outcomes, whilst only one subject was completely normal. Abnormal peripheral airway function was present in a large proportion of adult asthmatics at baseline. Reduced FEV1, a positive smoking history, and/or blood eosinophilia identified "a small airway asthma subtype" that might benefit from peripheral airway targeted therapy.

Clinical effects of purified air administered to the breathing zone in allergic asthma: A double-blind randomized cross-over trial.

BACKGROUND: Exposure to inhaled allergens is a pathogenetic factor in allergic asthma. However, most studies that previously looked at air cleaning devices have shown little or no effect on patients with perennial allergic asthma. AIMS AND OBJECTIVES: We examined a novel treatment using temperature regulated laminar airflow with a very low particle concentration directed to the breathing zone of teenagers and young adults with mild to moderate allergic asthma during night sleep. We hypothesised that the decreased allergen exposure during the night would have an effect on bronchial inflammation and quality of life. METHOD: Twenty-two patients (mean 18.8 years) were randomized to start with active or placebo treatment for 10 weeks. All patients received both active and placebo treatment with unfiltered air, with a 2-week wash-out period in between treatments. Maintenance treatment with inhaled corticosteroids was unaltered during the trial period. Health related quality of life (miniAQLQ) was the primary effectiveness measure. Exhaled nitric oxide (FeNO) and spirometry were also investigated. RESULTS: Active treatment resulted in an improved miniAQLQ compared to placebo (mean score 0.54, p<0.05, n=20). An effect on bronchial inflammation was also detected with significantly lower FeNO values during the active treatment period (mean -6.95 ppb, p<0.05, n=22). Both effects were evident after 5 weeks. The change in lung function was not statistically significant. CONCLUSION: Clean air, administered directly to the breathing zone during sleep, can have a positive effect on bronchial inflammation and quality of life in patients with perennial allergic asthma.

Downregulation of CXCR6 and CXCR3 in lymphocytes from birch-allergic patients.

Preferential expression of chemokine receptors on Th1 or Th2 T-helper cells has mostly been studied in cell lines generated in vitro or in animal models; however, results are less well characterized in humans. We determined T-cell responses through chemokine receptor expression on lymphocytes, and cytokine secretion in plasma from birch-allergic and healthy subjects. The expression of CCR2, CCR3, CCR4, CCR5, CCR7, CXCR3, CXCR4, CXCR6, IL-12 and IL-18R receptors was studied on CD4(+) and CD8(+) cells from birch-allergic (n = 14) and healthy (n = 14) subjects by flow cytometry. The concentration of IL-4, IL-5, IL-10, IL-12, IFN-gamma and TNF-alpha cytokines was measured in plasma from the same individuals using a cytometric bead array human cytokines kit. The similar expression of CCR4 in T cells from atopic and healthy individuals argues against the use of the receptor as an in vivo marker of Th2 immune responses. Reduced percentages of CD4(+) cells expressing IL-18R, CXCR6 and CXCR3 were found in the same group of samples. TNF-alpha, IFN-gamma, IL-10, IL-5, IL-4 and IL-12 cytokines were elevated in samples from allergic individuals. Reduced expression of Th1-associated chemokine receptors together with higher levels of Th1, Th2 and anti-inflammatory cytokines in samples from allergic patients indicate that immune responses in peripheral blood in atopic diseases are complex and cannot be simplified to the Th1/Th2 paradigm. Not only the clinical picture of atopic diseases but also the clinical state at different time points of the disease might influence the results of studies including immunological markers associated with Th1- or Th2-type immune responses.

Comparable morning versus evening administration of once-daily mometasone furoate dry powder inhaler.

BACKGROUND: The control of daytime and nighttime symptoms is an important measure of effectiveness of asthma therapy, especially, when administered once-daily. OBJECTIVE: To evaluate the efficacy of evening and morning administrations of mometasone furoate administered via a dry powder inhaler (MF-DPI) 400 microg once-daily (QD) to show equivalence. METHODS: Open-label, randomized, parallel-group study in adult patients with mild to moderate asthma with a > or = 3-month history of ICS use. Patients received MF-DPI 400 microg QD either in the morning (AM) or evening (PM) for 12 weeks. The primary measure was the change in asthma symptoms from baseline to week 12. Secondary outcomes included response to treatment, adherence, inhaler device evaluation, use of rescue medication, urinary cortisol levels, and differential white blood cell count. RESULTS: A total of 1537 patients were randomized; the efficacy population comprised 543 and 479 patients in the MF-DPI QD morning and evening groups, respectively. Mean improvements from baseline in daytime symptom scores at week 12 with morning and evening administration of MF-DPI 400 microg were -0.11+/-0.59 and -0.12+/-0.68, respectively (95% CI, -0.095 to 0.061) and the corresponding improvements in nighttime symptom scores were -0.08+/-0.59 and -0.07+/-0.50, respectively (95% CI, -0.067 to 0.068). Use of rescue medication was the same in both groups (1 puff/day). MF-DPI QD was well tolerated regardless of time of administration. CONCLUSIONS: This open-label study did not identify differences between morning and evening dosing of MF-DPI 400 microg QD. A better effect of evening dosing compared to morning dosing found in previous double-blind placebo-controlled studies could not be confirmed.

Impaired maturation of monocyte-derived dendritic cells from birch allergic individuals in association with birch-specific immune responses.

Optimal activation of T lymphocytes requires a costimulatory signal provided by the interaction of molecules on the surface of T cells with their ligands expressed on dendritic cells (DC). We investigated whether DC differentiated from monocytes from healthy and birch allergic asthmatic individuals and further maturated by stimulation with cat and birch allergens and LPS differ in their phenotypic receptor expression. Similar expression of DC surface markers, including HLA-DR, CD80, CD86, CD83, CD1a and CD11c, was detected in monocyte-derived DC from allergic and healthy individuals. Cells from healthy donors stimulated either antigen showed a similar activation of the CD80 and double CD80/CD86 costimulatory molecules when compared with non-stimulated cells. In the case of cells from allergic individuals, birch allergen was unable to produce the same increased expression of CD80 alone or in combination with CD80/CD86, in comparison with cells stimulated with cat and LPS. Levels of IL-6, IL-8, IL-10, MCP-1/MCAF and MIP-1beta were similar in the supernatant of non-stimulated DC from both groups of subjects. By contrast, the spontaneous secretion of IL-12p70 and TNF-alpha was higher in the supernatant of DC from healthy subjects when compared with that from allergic individuals. Stimulation with birch and LPS resulted in an increased secretion of IL-12p70 in samples from healthy when compared with that in allergic individuals. The results suggest an impaired specific maturation of DC from birch allergic individuals in association with birch-specific immune responses. Lower secretion of IL-12p70 from birch-stimulated DC from allergic individuals suggests that not only maturation, but also the specific Th1 function of these cells seems to be affected in those individuals.

Formoterol as needed with or without budesonide in patients with intermittent asthma and raised NO levels in exhaled air: A SOMA study.

Patients with mild intermittent asthma sometimes show signs of inflammation, and guidelines suggesting bronchodilator therapy alone as needed may be questioned. The current study compared as-needed use of a rapid-acting beta2-agonist with as-needed use of a beta2-agonist and corticosteroid combination as the only medication in asthma patients with intermittent symptoms. A total of 92 nonsmoking asthma patients (of 187 screened) using only an inhaled beta2-agonist as needed (28 males, 64 females; mean age 37 yrs; mean forced expiratory volume in one second (FEV1) 101% predicted, mean reversibility 6.5% pred and fractional exhaled nitric oxide (FeNO) > or =20 parts per billion (ppb)) were randomised to treatment with formoterol (Oxis Turbuhaler) 4.5 microg as needed (n = 47) or budesonide/formoterol (Symbicort Turbuhaler) 160/4.5 microg as needed (n = 45) in a double-blind, parallel-group 24-week study. The primary variable of efficacy was change in FeNO. Baseline FeNO was 60 ppb and 59 ppb in the budesonide/formoterol and formoterol groups, respectively. Mean reductions in FeNO in the budesonide/formoterol and formoterol groups were 18.2 ppb and 2.8 ppb, respectively (95% confidence interval (CI) 7.5-23.5 ppb). The reduction in the budesonide/formoterol group occurred during the first 4 weeks of treatment and remained at this low level. Mean FEV1 increased by 1.8% pred normal value in the budesonide/formoterol group and decreased by 0.9% pred normal value in the formoterol group (95% CI -4.7- -0.7). In the budesonide/formoterol group, use of > or =4 inhalations x day(-1) of study medication was seen on 21 treatment days compared with 74 in the formoterol group. In conclusion, as-needed use of an inhaled corticosteroid together with a rapid-acting bronchodilator may be more beneficial than a beta2-agonist alone in patients with intermittent asthma and signs of airway inflammation. The long-term benefits are unknown.

Urinary inflammatory mediators and inhalation of hypertonic saline in children.

BACKGROUND: The inflammatory mechanisms of hypertonic saline-induced bronchoconstriction are not well understood. METHODS: Seventeen asthmatics with (n=11) and without bronchial hyperresponsiveness (BHR) (n=6) and 18 randomly selected nonatopic nonasthmatic controls without BHR were evaluated by urine samples collected before and 1 h after hypertonic saline provocation test. Histamine, 11beta-PGF2alpha, and LTE4 were analysed by enzyme immunoassay (EIA) and eosinophil protein X (EPX) by radioimmunoassay (RIA). RESULTS: The levels of leukotriene E4 (LTE4) increased significantly after the challenge tests, both in the asthmatics (median: 354 pg/mg pre-challenge vs. 628 pg/mg post-challenge; P=0.05) and in the controls (median: 294 pg/mg pre-challenge vs. 460 pg/mg post-challenge; P <0.01). The levels of histamine also increased significantly in the latter (median: 299 micromol/mg pre-challenge vs. 569 micromol/mg post-challenge; P=0.03). However, the levels of 11beta-PGF2alpha and EPX did not change significantly after the challenge tests either in the asthmatics or in the controls. CONCLUSIONS: The inhalation of hypertonic saline increased urinary excretion of LTE4 both in the asthmatics and in the controls. The slight increase of leukotrienes was enough to induce airway obstruction in some of the asthmatics, because of the hyperresponsiveness in their airways.

Seasonal differences of peak expiratory flow rate variability and mediators of allergic inflammation in non-atopic adolescents.

Variations in peak expiratory flow (PEF) and serum eosinophil mediators were studied in healthy adolescents. Twenty-five boys and 31 girls, 11-16 years of age (mean age 14.3 years), were selected and investigated during the birch pollen season of 1995; 45 were also investigated during the autumn of the same year. The PEF was measured twice daily and eosinophil mediators in serum and in urine were measured by radioimmunoassay (RIA) once during the birch pollen season and once in autumn. The type values of the daily PEF variation, expressed in amplitude percentage mean, were 6.4 and 3.9%, mean values were 7.35 and 6.74%, and the 95th percentiles were 18 and 14%, during the birch pollen season and autumn, respectively. The 95th percentiles were 41 and 38 microg/l for serum eosinophil cationic protein (s-ECP), 74 and 62 microg/l for serum eosinophil protein X (s-EPX), 987 and 569 microg/l for serum myeloperoxidase (s-MPO), and 165 and 104 microg/mmol for urinary eosinophil protein X/urinary creatinine (u-EPX/u-creatinine), during the birch pollen season and autumn, respectively. The levels of the eosinophil mediators decreased significantly from May (n = 56) to November (n = 45), for s-ECP from a median value of 14 microg/l to 7 microg/l (p= 0.001), for s-EPX from a median value of 28 microg/l to 20 microg/l (p= 0.001), and for the neutrophil mediator, s-MPO, from a median value of 440 g/l to 292 g/l (p< 0.001). The PEF variability decreased significantly (p= 0.037), from spring (n = 55; median 8%, 95% confidence interval [CI] 7.8-10.19) to autumn (n = 44; median 6%, 95% CI 6.1-8.9). A significant correlation was found between the levels of s-ECP and s-EPX (rs = 0.7, p< 0.001), between s-ECP and s-MPO (rs = 0.6, p< 0.001), between s-EPX and s-MPO (rs = 0.4, p< 0.005), and between s-EPX and u-EPX/u-creatinine (rs = 0.6, p< 0.0001), in the birch pollen season (n = 56) and in the autumn (n = 45). There was a positive correlation found in PEF variability between the two seasons (n = 43; rs = 0.5, p= 0.0006). No other correlation was found between PEF variability and any other parameters. The difference in the levels of eosinophil mediators between seasons in non-atopic, healthy children is unexplained. Normal limits for mediators were higher and PEF variability was almost the same as has been reported in adults. When using normal values, seasonal influences should be considered.

Improved asthma control with budesonide/formoterol in a single inhaler, compared with budesonide alone.

Budesonide/formoterol in a single inhaler was compared with budesonide alone, and with concurrent administration of budesonide and formoterol from separate inhalers, in patients with asthma, not controlled with inhaled glucocorticosteroids alone. In this 12-week, double-blind, randomized, double-dummy study, 362 adult asthmatics (forced expiratory volume in one second 73.8% of predicted, inhaled glucocorticosteroid dose 960 microg x day(-1)) received single inhaler budesonide/formoterol (Symbicort Turbuhaler) 160/4.5 microg, two inhalations b.i.d., or corresponding treatment with budesonide, or budesonide plus formoterol via separate inhalers. There was a greater increase in morning peak expiratory flow (PEF) with single-inhaler (35.7 L x min(-1)) and separate-inhaler (32.0 L x min(-1)) budesonide and formoterol, compared with budesonide alone (0.2 L x min(-1); p<0.001, both comparisons); the effect was apparent after 1 day (p<0.001 versus budesonide, both comparisons). Similarly, evening PEF, use of rescue medication, total asthma symptom scores and percentage of symptom-free days improved more with both single inhaler and separate inhaler therapy than with budesonide alone, as did asthma control days (approximately 15% more, p<0.001 versus budesonide, both comparisons, with a marked increase in the first week). All treatments were well tolerated and the adverse event profile was similar in all three treatment groups. It is concluded that single inhaler therapy with budesonide and formoterol is a clinically effective and well-tolerated treatment for patients with asthma that is not fully controlled by inhaled glucocorticosteroids alone.