A recent study adds a unique finding to the mystery of sudden infant death syndrome (SIDS). Results show that infants who died from SIDS had impaired hearing in their right ear.
The study compared 31 infants who died from SIDS with 31 infants who survived the first year of life. Their records were reviewed to compare their newborn hearing screening tests. The babies who died from SIDS had decreased signal-to-noise ratios at three frequencies: 2, 3 and 4 kHz.
The study appears in the journal Early Human Development. It was published online on July 5 before coming out in print.
According to the National Institute of Child Health and Human Development, SIDS is the sudden, unexplained death of an infant younger than one year old. It is the leading cause of death in children between one month and one year of age. Most SIDS deaths happen when babies are between 2 months and 4 months of age.
The cause of SIDS is unknown. Studies show that babies who sleep on their back have a lower risk of SIDS than babies who sleep on their stomach. In 2006 a study linked SIDS to a brainstem abnormality.
The nerve responsible for hearing is attached to the brainstem. The nerve also is involved with position sense and helps with balance. It is possible that this nerve may be damaged in children who die from SIDS.
There is no predictive test for SIDS. It is only identified after the child dies. The unique finding of the current study indicates that a hearing test may help identify infants who are at risk of SIDS.
A simple hearing test often is performed before a child leaves the hospital. Doctors and parents who know a child is at risk for SIDS could take steps to prevent it from occurring.
