Variability in total serum IgE over 1 year in severe asthmatics

Abstract

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 tot ) in asthmatics remains poorly documented. Methods In this prospective study, sIgE 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 β 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 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 6 ). The sIgE tot variability and factors predictive for this variability were studied, as well as ACQ 6 outcomes. Results The variation in sIgE 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 tot subgroups, respectively. The residual within-patient variability was therefore limited. In 10/41 patients, sIgE 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 tot and ACQ 6 score over all time points (r = 0.15, p = 0.02), but sIgE tot failed to associate with severe exacerbation. sIgE 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 tot levels was observed over 1 year as opposed to marked between-subject variability. sIgE tot decreases with age. Variation in sIgE tot weakly associates with asthma control but not with exacerbation.

Replication study of susceptibility variants associated with allergic rhinitis and allergy in Han Chinese

“…This outcome may result from a link between innate immunity and IgE-mediated adaptive immune responses in asthma. The variation of serum total IgE also showed have an association with asthma control [35], which might also increase the risk of AR. Besides, our findings also reinforced the notion that there was a shared genetic etiology of allergic and autoimmune disease, with discovered susceptibility loci for allergy, many of which were previously associated with autoimmune disease [12].…”

Prediction of clinical response to omalizumab in moderate-to-severe asthma patients using the change in total serum IgE level

“…In a prospective study including 41 severe asthmatics, serum IgE levels were measured over 1 year at 7 time points, and the results showed that there was limited within-patient variability of IgE levels (25). This finding suggests that measurement of total IgE is a stable method to determine management.…”

Seasonal variation in total and pollen‐specific immunoglobulin E levels in the European Community Respiratory Health Survey

“…One study of 17 patients with allergic rhinitis/asthma found significantly higher total IgE level during the grass pollen season 4 but another study of 47 patients with severe asthma showed little seasonal variation. 8 Perhaps, the negative result for total IgE is unsurprising as total IgE likely reflects reactivity to all allergens, each with different seasonal patterns. The higher level seen in summer months in the single centre in USA (Portland) may reflect other regional pollen seasons that were not considered in this study, for example, ragweed.…”