Predisposing factors for acute otitis media in infancy

SummaryBackgroundFactors predisposing to acute otitis media (AOM) are not thoroughly understood.ObjectivesIn this study we prospectively investigated incidence rates and risk factors of AOM in a systematic sample of infants in a well-defined population.Design and subjectsFollowing interview soon after delivery in a representative sample of 1049 mother–infant pairs, information was collected 1, 3, 6, 9 and 12 months after birth. Episodes of AOM were recorded as by parental reports of diagnosis made by a physician. AOM frequency was further analyzed against 21 social, maternal, paternal, prenatal, perinatal and infantile factors.ResultsSuccessful 12-month follow-up was achieved for 926/1049 infants (88.3%), of whom 265 (28.6%) were reported with episodes of AOM; 153 with a single, 55 with two, and 57 with three to six episodes (16.5%, 5.94%, and 6.16% respectively). Factors founded by multivariate analysis to predispose to AOM included presence of siblings (P < 0.001), out-of-home daycare (P < 0.001), ill health in pregnancy (P < 0.01), and suboptimal breastfeeding (P < 0.01). Multiple (3 or more) episodes were related to presence of siblings (P < 0.0001), out-of-home daycare (P < 0.001), ill health in pregnancy (P < 0.001), and low parental education (P < 0.001). 28 infants were hospitalized (10.6% of infants with AOM, 3.02% of the total cohort). Hospitalization was related to young maternal age (P < 0.05).ConclusionsOur findings confirm the high morbidity of AOM during infancy and point to several infant- and family-related predisposing factors, some of which are liable to intervention.