Sputum eosinophilia and maximal airway narrowing in Dermatophagoides pteronyssinus allergic rhinitis patients: only rhinitis or rhinitis plus mild asthma?

The complex link between severity of asthma and rhinitis in mite allergic patients

AIM

The aim of the study was to evaluate the link between the severity of upper and lower airways diseases in mite allergic patients with respiratory allergy.

PATIENTS AND METHOD

A multicentre, observational, cross-sectional study was carried out in 556 consecutively enrolled mite allergic patients with rhinitis and asthma comorbidity attending a specialist unit. Severity assessment of rhinitis and asthma was evaluated in accordance with ARIA and GINA guidelines.

RESULTS

Reliable data were available for 518 patients. The distribution of rhinitis severity was: 15.6% mild intermittent rhinitis, 4.4% moderate-severe intermittent rhinitis, 30.3% mild persistent rhinitis and 49.6% moderate persistent rhinitis. The distribution of asthma severity was: 41.3% mild intermittent asthma, 14.3% mild persistent asthma, 19.1% moderate persistent asthma and 25.3% severe persistent asthma. In patients with moderate-severe persistent rhinitis (49.5%) a significant trend (p = 0.005) was found pointing to an increased link with asthma severity.

CONCLUSION

A link between respective severities of rhinitis and asthma was found in only half of mite allergic patients with rhinitis and asthma.

Comparison of deltaFVC between patients with allergic rhinitis with airway hypersensitivity and patients with mild asthma

BACKGROUND

In asthmatic individuals, airway sensitivity and maximal airway response are increased. Airway sensitivity is usually evaluated by measuring the provocation concentration of inhaled methacholine or histamine that causes a decrease in forced expiratory volume in 1 second of 20% (PC20). The percentage decrease in forced vital capacity at the PC20 (deltaFVC) has been proposed as a surrogate marker for maximal airway response. Individuals with allergic rhinitis and no clinical evidence of asthma frequently exhibit airway hypersensitivity.

OBJECTIVE

To compare the deltaFVC between patients with allergic rhinitis and mild asthmatic patients with a similar degree of airway hypersensitivity.

METHODS

A retrospective analysis of methacholine challenge test data from 72 children with allergic rhinitis and airway hypersensitivity (methacholine PC20 < 16 mg/mL) (rhinitis group) and from 72 children with mild atopic asthma matched to the rhinitis group regarding the methacholine PC20 (asthma group). The deltaFVC was calculated on the concentration-response curve to methacholine.

RESULTS

The mean +/- SD deltaFVC was significantly lower in the rhinitis group (15.0% +/- 3.6%) vs the asthma group (17.4% +/- 5.3%) (P = .002). There was no significant correlation between the deltaFVC and PC20 in the rhinitis (r = -0.101; P = .41) and asthma (r = -0.023; P = .85) groups when 2 patients with PC20 less than 1 mg/mL were excluded from each group.

CONCLUSIONS

Patients with allergic rhinitis and airway hypersensitivity had a significantly lower deltaFVC than methacholine PC20-matched mild asthmatic patients, suggesting that the level of maximal airway response in patients with allergic rhinitis is lower than that in mild asthmatic patients with a similar degree of airway hypersensitivity.

The connection between allergic rhinitis and bronchial asthma

PURPOSE OF REVIEW

The relationship between allergic rhinitis and asthma has intrigued practicing physicians since the turn of the century. Investigations during the past two decades have led to an increased understanding of this relationship.

RECENT FINDINGS

A growing body of evidence clearly demonstrates that patients with allergic rhinitis, in the absence of asthma, have distinct abnormalities of lower airway function, including alterations in physiology, histology and biochemistry. In addition, epidemiologic surveys have consistently shown allergic rhinitis as an independent risk factor for developing asthma, and that preexisting abnormalities in lung function may predispose to lower airway disease development. Clinical trials show that specific allergen immunotherapy for children and adults with seasonal allergic rhinitis reduces the risk of developing asthma. In patients with established asthma and concomitant allergic rhinitis, several medications have significant effects upon the upper and lower airways, including intranasal corticosteroids, oral antihistamines, and leukotriene receptor antagonists.

SUMMARY

Our understanding of the natural history of allergic rhinitis could lead to improvements in early intervention, potentially preventing the progression of allergic rhinitis to asthma. Aggressive treatment of rhinitis in patients with concomitant asthma may enhance asthma outcomes and quality of life for all patients with these chronic diseases.

Sputum eosinophil counts and eosinophil cationic protein levels in cough-variant asthma and in classic asthma, and their relationships to airway hypersensitivity or maximal airway response to methacholine

BACKGROUND

The aims of this study were to compare the degree of airway inflammation in cough-variant asthma (CVA) with that in classic asthma (CA), and to examine the relationship between airway inflammation and airway hypersensitivity or maximal airway response to methacholine in both conditions.

METHODS

Sputum was induced in 41 CVA patients, in 41 methacholine PC(20)-matched CA patients, and in 20 healthy children. The sputum samples were analyzed for total and differential cell counts, and for eosinophilic cationic protein (ECP). A high-dose methacholine challenge test was performed in CVA and CA patients to determine PC(20) and maximal airway response.

RESULTS

Sputum eosinophil percentages and ECP levels were significantly elevated in CVA and CA vs the control, but no significant differences were found between the two asthma groups. In the two asthma groups, neither sputum parameters correlated significantly with methacholine PC(20). However, the absence of a maximal response plateau or its higher level, when present, was associated with increased eosinophil percentages and ECP levels in the CVA group.

CONCLUSIONS

The degree of eosinophilic inflammation may not be causally related to differences in presented asthma manifestations. The identification of a maximal response plateau and the level of this plateau in patients with CVA may provide information pertinent to airway eosinophilic inflammation.

Can a self-management programme delivered by a community pharmacist improve asthma control? A randomised trial

BACKGROUND

No randomised studies have addressed whether self-management for asthma can be successfully delivered by community pharmacists. Most randomised trials of asthma self-management have recruited participants from secondary care; there is uncertainty regarding its effectiveness in primary care. A randomised controlled study was undertaken to determine whether a community pharmacist could improve asthma control using self-management advice for individuals recruited during attendance at a community pharmacy.

METHODS

Twenty four adults attending a community pharmacy in Tower Hamlets, east London for routine asthma medication were randomised into two groups: the intervention group received self-management advice from the pharmacist with weekly telephone follow up for 3 months and the control group received no input from the pharmacist. Participants self-completed the North of England asthma symptom scale at baseline and 3 months later.

RESULTS

The groups were well matched at baseline for demographic characteristics and mean (SD) symptom scores (26.3 (4.8) and 27.8 (3.7) in the intervention and control groups, respectively). Symptom scores improved in the intervention group and marginally worsened in the control group to 20.3 (4.2) and 28.1 (3.5), respectively (p<0.001; difference adjusted for baseline scores=7.0 (95% CI 4.4 to 9.5).

CONCLUSIONS

A self-management programme delivered by a community pharmacist can improve asthma control in individuals recruited at a community pharmacy. Further studies should attempt to confirm these findings using larger samples and a wider range of outcome measures.