Risk factors and etiology of childhood hearing loss: a cohort review of 296 subjects.

Background: The association between the Joint Committee on Infant Hearing (JCIH) risk factors and etiology of hearing loss (HL) is not studied well in children.Objectives: To clarify the etiologic causes and evaluate the JCIH risk characteristics of children with HL.Methods: A retrospective study of 296 children with HL born between 2009.01 and 2013.12 in Stokholm. Demographic data, family and medical histories, audiologic results, imaging findings, and genetic results were ascertained and analyzed.Results: In 221 with bilateral hearing loss (BHL), family history and neonatal risk indicators were the most common risks (59 each), followed by syndrome related risks. In 75 with unilateral hearing loss (UHL), craniofacial anomaly was the most common risk, followed by family history. Etiology was established in 93 with BHL, in which syndromic HL accounted for 37.2%, chromosomal aberrations for 21.3%, and environmental causes for 19.1%. Etiology was established in 35 with UHL, in which ear malformation accounted for the most (74.3%), followed by environmental causes (14.3%).Conclusions and significance: Childhood HL can be attributed to a variety of causes with an etiology identifiable in 42.5% of BHL and 46.7% of UHL. BHL and UHL have different patterns of JCIH risk exposure and etiology.