부산대학교 도서관

Background Immunoglobulin E (IgE) is the treatment target of omalizumab, a monoclonal antibody indicated in the treatment of severe allergic asthma. Long-term variability of serum total IgE (sIgE.sub.tot) in asthmatics remains poorly documented. Methods In this prospective study, sIgE.sub.tot levels were measured over 1 year at 7 time points in 41 severe asthmatics treated with high-dose of inhaled corticosteroids and long-acting [beta].sub.2 agonists. 33 patients were atopic based on at least one positive RAST to common aeroallergens. Patients were divided into three groups according to their baseline sIgE.sub.tot level: low (< 76 IU/mL; n = 10), intermediate (76-700 IU/mL; n = 20) or high (> 700 IU/mL; n = 11). Patients also completed the six-item Juniper Asthma Control Questionnaire (ACQ.sub.6). The sIgE.sub.tot variability and factors predictive for this variability were studied, as well as ACQ.sub.6 outcomes. Results The variation in sIgE.sub.tot level was mostly the consequence of between patient-variability, which represented 96%, 71% and 96% of the total variability in the low, intermediate and high sIgE.sub.tot subgroups, respectively. The residual within-patient variability was therefore limited. In 10/41 patients, sIgE.sub.tot levels increased or decreased, for at least one visit, beyond the predefined range of the subgroups to which they were assigned (< 76 IU/mL; 76-700 IU/mL; > 700 IU/mL). There was a significant but weak correlation between sIgE.sub.tot and ACQ.sub.6 score over all time points (r = 0.15, p = 0.02), but sIgE.sub.tot failed to associate with severe exacerbation. sIgE.sub.tot decreased by 3% with any additional year of age for the whole group (p = 0.01) and increased by 5% per one unit of allergen exposure score in atopic patients (p = 0.002). Conclusion In severe asthmatics, limited within-patient variability of sIgE.sub.tot levels was observed over 1 year as opposed to marked between-subject variability. sIgE.sub.tot decreases with age. Variation in sIgE.sub.tot weakly associates with asthma control but not with exacerbation. Keywords: Asthma, IgE, Variability
Author(s): Renaud Louis[sup.1] , Charles Pilette[sup.2] , Olivier Michel[sup.3] , Alain Michils[sup.4] , Guy Brusselle[sup.5] , Antoine Poskin[sup.6] , Jan Van Schoor[sup.6] , Kris Denhaerynck[sup.7,8] , Stefaan Vancayzeele[sup.6] , Ivo [...]