Abstract

Objectives.: To compare the cow's milk protein allergy (CMPA) prevalence in 2 cohorts of children from different socioeconomic strata. Methods.: Prospective birth cohort that included patients from 2 hospitals providing care for a low- and high income population, respectively. Healthy newborns ≥34 gestational weeks were recruited and followed up to 12 months by a monthly telephone survey. If ≥2 predefined symptoms/signs suggestive of CMPA were detected, the patient was evaluated by a gastroenterologist. Diagnosis was confirmed by exclusion diet followed by open oral food challenge. Results.: Overall the prevalence of CMPA was 5.2%, with a 6 times higher prevalence in the high income cohort (9.2%) compared with the low income group (1.5%; RR 6,2; 95%CI 1.8-20.7; p = 0.0005). All the cases were non-IgE mediated with predominantly gastrointestinal symptoms. High income cohort did have higher frequency of C-section, mother's previous chronic disease, mother's history of atopy/food allergy, older age and higher educational level of parents. Parent smoking and presence of pets at home were more frequent in the low income cohort.Multiple logistic regression showed the high income cohort did have older age and higher educational level of both parents. Conclusion.: In these cohorts the prevalence of CMPA was higher than reported previously in other developing countries and significantly higher in the high income group. Our findings were associated with sociodemographic characteristics of the parents.