Biomedical subjects

Walter Vincken

Publications and source records attributed to Walter Vincken.

23 records · Page 2Linked to original sources

PubMed2003

Fenoterol delivery by Respimat soft mist inhaler versus CFC metered dose inhaler: cumulative dose-response study in asthma patients.

OBJECTIVES: Respimat (RMT) soft mist inhaler (SMI) is a novel, propellant-free alternative to chlorofluorocarbon metered-dose inhalers (CFC-MDIs). The aim of this study was to evaluate the safety and establish the equipotent dose of fenoterol delivered by RMT SMI vs. a conventional MDI. DESIGN: Double-blind, randomized, crossover, comparative study between fenoterol inhaled via RMT (either 50 microg/actuation, RMT50; or 100 microg/actuation. RMT100) and MDI (100 microg/actuation; MDI100). PATIENTS AND INTERVENTIONS: A total of 41 asthma patients received cumulative doses of fenoterol 600 microg (RMT50) or 1200 microg (RMT100 and MDI100) on 3 test days. MEASUREMENTS AND RESULTS: The bronchodilator response (forced expiratory volume in 1 second [FEV1]) was considered therapeutically equivalent (i.e., noninferior) if the 95% confidence intervals for the difference in their mean changes from baseline were within limits of +/- 0.15L. Systemic exposure was evaluated from plasma fenoterol levels. Adverse events (AEs) were recorded. RMT50 and RMT100 produced noninferior bronchodilatation to MDI100 from 30minutes after the first dose. RMT50 showed equivalent safety and tolerability to MDI100, whereas RMT100 produced a higher incidence of AEs, a significantly greater plasma potassium reduction and a significant increase in pulse rate. Fenoterol plasma levels were twice as high with RMT100 as with RMT50 or MDI100. CONCLUSIONS; The nominal dose of fenoterol administered via RMT SMI can be at least halved to achieve equivalent efficacy, safety, and tolerability to a MDI.

Administration, Inhalation↗

PubMed2003

Associations between bronchial hyperresponsiveness and immune cell parameters in patients with chronic fatigue syndrome.

STUDY OBJECTIVE: To examine whether bronchial hyperresponsiveness (BHR) in patients with chronic fatigue syndrome (CFS) is caused by immune system abnormalities. DESIGN: Prospective comparative study. SETTING: A university-based outpatient clinic (Vrije Universiteit; Brussels, Belgium). PARTICIPANTS: One hundred thirty-seven CFS patients and 27 healthy volunteers. MEASUREMENTS: Pulmonary function testing, histamine bronchoprovocation test, immunophenotyping, and ribonuclease (RNase) latent determination. RESULTS: Seventy-three of 137 patients presented with BHR, of whom 64 had normal results of the histamine bronchoprovocation test. No significant differences were found in age or sex characteristics between the groups. There were no differences in the RNase L ratio, total lung capacity, or FEV(1)/FVC ratio between CFS patients with or without BHR. The group of patients in whom BHR was present (BHR+) differs most significantly from the control group with eight differences in the immunophenotype profile in the cell count analysis and seven differences in the percentage distribution profile. The group of patients in whom no BHR was detected (BHR-) only differed from the control subjects in CD25+ count and in the percentage of CD25+ cells. We observed a significant increase in cytotoxic T-cell count and in the percentage of BHR+ patients compared to BHR- patients, which is consistent with the significant reduction in percentage naïve T cells. CONCLUSIONS: These results refute any association between the cleaving of 80 kd RNase L and BHR. Immunophenotyping of our sample confirmed earlier reports on (chronic) immune activation in patients with CFS, compared to healthy control subjects. BHR+ CFS patients have more evidence of immune activation compared to BHR- patients. Inflammation and the consequent IgE-mediated activation of mast cells and eosinophils, as seen in asthma patients, is unlikely to be responsible for the presence of BHR in patients with CFS.

Adult↗

PubMed2002

Nonreversible conductive airway ventilation heterogeneity in mild asthma.

A multiple-breath washout technique was used to assess residual ventilation heterogeneity in the conductive and acinar lung zones of asthmatic patients after maximal beta(2)-agonist reversibility. Reversibility was assessed in 13 patients on two separate visits corresponding to a different baseline condition in terms of forced expiratory volume in 1 s [FEV(1); average FEV(1) over 2 visits: 92 +/- 21% of predicted (SE)]. On the visit corresponding to each patient's best baseline, 400 micro g salbutamol led to normal acinar ventilation heterogeneity, normal FEV(1), and normal peak expiratory flow; i.e., none was significantly different from that obtained in 13 matched controls. By contrast, conductive ventilation heterogeneity and forced expiratory flow after exhalation of 75% forced vital capacity remained significantly different from controls (P < or = 0.005 on both indexes). In addition, the degree of postdilation conductive ventilation heterogeneity was similar to what was previously obtained in asthmatic individuals with a 19% lower baseline FEV(1) and twofold larger acinar ventilation heterogeneity (Verbanck S, Schuermans D, Noppen M, Van Muylem A, Paiva M, and Vincken W. Am J Respir Crit Care Med 159: 1545-1550, 1999). We conclude that, even in the mildest forms of asthma, the most consistent pattern of non-beta(2)-agonist-reversible ventilatory heterogeneity is in the conductive lung zone, most probably in the small conductive airways.

Adrenergic beta-Agonists↗

PubMedDate not supplied

Systemic corticosteroid therapy for acute asthma exacerbations.

Acute exacerbations of asthma may represent reactions to airway irritants or failures of chronic treatment. The costs to both the patient and society are high. Exacerbations often are frightening episodes that can cause significant morbidity and sometimes death. The emergency department (ED) visits and hospitalizations often required lead to significant health care expenses. Thus, preventing and optimizing management of acute exacerbations is critical. Corticosteroids are a cornerstone of asthma therapy. They have been shown to lower admission rates and reduce risk of relapse. This article provides an overview of the role of corticosteroids (including betamethasone, dexamethasone, methylprednisolone, and prednisolone) in the management of acute asthma exacerbations, with an aim toward effective decision making about the choice of therapy.

Administration, Oral↗

PubMedDate not supplied

Objective assessment of lower airway involvement in chronic rhinosinusitis.

BACKGROUND: When associated with lower airway involvement, the morbidity and the cost of chronic rhinosinusitis (CRS) can increase. The aim of this prospective study was to assess the clinical and radiological characteristics of the upper airways in CRS patients scheduled for functional endoscopic sinus surgery and to correlate these findings with the functional changes of the lower airways. METHODS: Twenty-five adult patients with CRS were subjected to clinical and endoscopic assessments, computed tomography scan, and allergic assessments using validated scoring systems. Lower airways were assessed by clinical history, pulmonary function test, histamine bronchial provocation test, and chest x rays. RESULTS: Sixty percent of CRS patients were shown to have associated lower airway involvement, i.e., 24% had asthma and 36% had small airway disease (SAD). Nasal congestion and nasal polyps were the most common clinical findings in both of these subgroups of patients. In addition, there was a negative correlation between computed tomography scan findings of the sinuses and the obstructive parameters on pulmonary function test in SAD but not in the asthma subgroup. CONCLUSION: These results showed that different kinds of lower airway involvement frequently could be associated with CRS. Some are manifest such as asthma and some are hidden such as SAD and histamine bronchial hyperresponsiveness.

Adult↗