Association of Asthma with Serum IgE Levels and Skin-Test Reactivity to Allergens

TLDR

The study examined the link between self‑reported asthma or allergic rhinitis and serum IgE levels plus skin‑test reactivity in 2,657 participants from a general‑population cohort. Asthma prevalence correlates strongly with age‑ and sex‑standardized serum IgE, with a linear increase in odds per IgE unit, while allergic rhinitis is linked mainly to skin‑test reactivity independent of IgE, indicating that asthma is predominantly IgE‑mediated and blurring the allergic/nonallergic distinction.

Abstract

We investigated the association of self-reported asthma or allergic rhinitis with serum IgE levels and skin-test reactivity to allergens in 2657 subjects in a general-population study. Regardless of the subjects' status with respect to atopy or their age group, the prevalence of asthma was closely related to the serum IgE level standardized for age and sex (P less than 0.0001), and no asthma was present in the 177 subjects with the lowest IgE levels for their age and sex (greater than 1.46 SD below the mean). The log odds ratio increased linearly with the serum IgE level after we controlled for possible confounders and the degree of reactivity to skin tests. In contrast, allergic rhinitis appeared to be associated primarily with skin-test reactions to common aeroallergens, independently of the serum IgE level. We conclude that asthma is almost always associated with some type of IgE-related reaction and therefore has an allergic basis, although not all the allergic stimuli that cause asthma appear to have been included in the battery of common aeroallergens we used to assess atopic status. These findings challenge the concept that there are basic differences between so-called allergic ("extrinsic") and nonallergic ("intrinsic") forms of asthma.