Self-reported food allergy in the elderly - Lifetime prevalence and clinical features in older adults seeking allergy care in Brazil.

BACKGROUND

Food allergy (FA) is a growing concern worldwide. However, most epidemiological studies focus on childhood or young adults, so that FA in the elderly remains poorly characterised. This study aimed to investigate the lifetime prevalence of self-reported FA among older Brazilians seeking allergy care, and possible associations with sociodemographic and clinical characteristics.

METHODS

Cross-sectional study using a self-reported questionnaire (developed, standardised and validated in Portuguese) applied to a non-probabilistic sample of elderly people (≥60 years) living in Brazil and recruited by their attending physicians in public or private care units. Multivariable regression models were applied to estimate the association of sociodemographic or clinical characteristics with self-reported FA.

RESULTS

We included 632 individuals (69.8% female; average age: 70.2 years) from all 5 Regions of Brazil. The prevalence of self-reported FA was 18.8% (95%CI = 16.0%-22.1%), based on the affirmative answer to the question: "have you ever had an allergic reaction to any food?". A total of 9.0% (7.0%-11.5%) reported having had a medical diagnosis of FA, while 5.5% (4,0%-7,6%) reported having had an immediate reaction (<2 h) and 2 or more episodes with the same food. The foods most frequently associated were shellfish, milk and fresh fruits. The most frequent clinical manifestations were urticaria and gastrointestinal symptoms. In multivariable analysis, we found an association between FA and female sex, as well as personal and family history of allergy.

CONCLUSIONS

The lifetime prevalence of self-reported FA among elderly individuals recruited in allergy/immunology clinical settings in Brazil was high, being more common in women and in those with personal or family history of allergy.