Perceived Versus Actual Aeroallergen Sensitization in Urban Children

This study analyzed the correlations between perceived and actual sensitization to indoor and outdoor allergens.

Participants included 253 children in an urban general and subspecialty pediatric clinic setting. They were 13.5 years old on average and identified as White (43.99%), Black (15.4%), 24.1% Latino (24.1%), Asian (7.5%), or Multiracial (8.3%). Most children had a family history of atopy (75.7%), and about half had a history of allergic rhinitis (50.2%) and asthma (46.6%).

Participants completed a questionnaire along with their parent and gave a peripheral blood sample. Specific immunoglobulin E (sIgE) levels were measured for ten aeroallergens. Statistical analyses included student’s t test, Fisher exact, Cohen’s κ tests, multivariable logistic regression models, and adjusted odds ratios.

Perceived sensitization was seen in 63.6%, while 80.2% were in fact sensitized based on blood test (sIgE ≥ 0.35 kU_A/L). Concordance between perceived and actual sensitization was fair (κ = 0.21–0.4) for 7 out of 10 allergens tested. This agreement was moderate for cat (κ = 0.42) and slight for mouse and cockroach. For cat, the odds of actual sensitization in a person who perceived cat allergy was 6 times that of a child who did not perceive cat allergy (adjusted odds ratio, 5.82). For mouse and cockroach, perceived allergy (8.3 and 10.3% respectively) and actual sensitization (17 and 36.8% respectively) varied significantly. In children with no perceived sensitization to any allergen, actual sensitization was as high as 30.4%, and found more commonly with indoor aeroallergens.

Individual aeroallergen sensitization in urban children is more likely to occur in children who perceive an allergy. After adjusting for confounders, cat and dust allergy had the strongest agreement between perceived and actual sensitization. Children who do not have perceived allergy may still have sensitization.

The authors’ thorough analyses including adjustments for confounding variables, and sensitization threshold foster confidence in these results. For most common allergens, there is a discordance between perceived and actual sensitization. The important implication is that individuals may undertake expensive or unnecessary avoidance measures or, conversely, maintain exposure to an allergen trigger without realizing the impact on health because of misperception of allergic triggers. The results support performing tests judiciously when clinically appropriate to do so based on the history. Further studies like this one should be performed with inclusion of allergic symptoms in addition to sensitization.