Risk factors for permanent childhood hearing impairment.
22 January 2020
This study looked at whether there is a link between gestational length of a child (the length of time of pregnancy) and the likelihood of permanent hearing impairment. The authors looked at data from over 19,000 children from a study called the Millennium Cohort Study. They found that shorter gestational length did not increase the likelihood of childhood permanent hearing impairment. However, they found that children who had neonatal illness (illness in the immediate days after birth), if they were Bangladeshi or Pakistani in ethnicity, or if they were born to younger mothers.
Objective While several perinatal risk factors for permanent childhood hearing impairment (PCHI) are known, association with gestational length remains unclear. We hypothesised that shorter gestational length predicts higher PCHI risk.
Design 19 504 participants from the UK Millennium Cohort Study (born 2000–2002, prior to newborn screening).
Methods Multivariable discrete-time survival analysis to examine associations between parent-reported PCHI by age 11 years and gestational length, plus other prespecified factors.
Results PCHI affected 2.1 per 1000 children (95% CI 1.5 to 3.0) by age 11; however, gestational length did not predict PCHI risk (HR, 95% CI 1.00, 0.98 to 1.03 per day increase). Risk was increased in those with neonatal illness, with or without admission to neonatal care (6.33, 2.27 to 17.63 and 2.62, 1.15 to 5.97, respectively), of Bangladeshi or Pakistani ethnicity (2.78, 1.06 to 7.31) or born to younger mothers (0.92, 0.87 to 0.97 per year).
Conclusion Neonatal illness, rather than gestational length, predicts PCHI risk. Further research should explore associations with ethnicity.