The Heritability of Otitis Media: A Twin and Triplet Study

Abstract

CONTEXT: Anatomical, physiological, and epidemiological data indicate that there may be a significant genetic component to prolonged time with and recurrent episodes of otitis media in children. OBJECTIVE: To determine the genetic component of time with and episodes of middle ear effusion and acute otitis media (AOM) during the first 2 years of life. DESIGN: Prospective twin and triplet cohort study with enrollment from 1982 through 1995. SETTING: Otitis Media Research Center in the ear, nose, and throat clinic of Children's Hospital of Pittsburgh, Pittsburgh, Pa. PATIENTS: A total of 168 healthy same-sex twin and 7 triplet sets were recruited within the first 2 months of life; zygosity results were available for 140 sets; 138 (99%) of these were followed up for 1 year and 126 (90%) for 2 years. MAIN OUTCOME MEASURES: Proportion of time with middle ear effusion, episodes of middle ear effusion, and episodes of AOM by zygosity status. RESULTS: At the 2-year end point, the estimate of heritability of time with middle ear effusion was 0.73 (P<.001). The estimates of discordance for 3 or more episodes of middle ear effusion were 0.04 for monozygotic twins and 0.37 for dizygotic twins (P = .01). The estimate of discordance of an episode of AOM in monozygotic twins was 0.04 compared with 0.49 in dizygotic twins (P = .005). CONCLUSIONS: Our study suggests there is a strong genetic component to the amount of time with middle ear effusion and episodes of middle ear effusion and AOM in children.