Early Onset of Presbyacusis in Persons with Down Syndrome
Dr. Buchanan was the first to discover that individuals with Down syndrome have an early onset of presbyacusis (hearing loss due to aging), which is consistent with premature aging observed in persons with Down syndrome. We all lose some of our high frequency (high pitch) hearing as we age, but this occurs at a much earlier age in people with Down syndrome. Individuals with Down syndrome appear to develop presbyacusis approximately 20-30 years earlier than other individuals with intellectual disabilities, and about 30-40 years earlier than persons in the general population. Dr. Buchanan’s research further showed that by age 40 years, persons with Down syndrome have a substantial hearing disability and should be considered for hearing aids to improve their speech understanding/auditory discrimination ability. In the general population, age-related hearing loss does not begin to affect significantly speech understanding abilities until about 60-70 years of age. Since Dr. Buchanan’s initial discovery, others have verified these findings. The research findings further suggest that before Alzheimer disease or cognitive decline is diagnosed in a person with Down syndrome, hearing loss due to aging should be ruled out. During the early stages of an age-related hearing loss, most individuals are able to hear voices and vowel sounds with relative ease (because of good low frequency hearing), but they may have problems understanding speech because of difficulty hearing the high frequency consonant sounds. That is, the person can hear speech, but has difficulty understanding it. This frequently leads to misinterpretation of what is said, and the individual may respond inappropriately, consequently appearing to be senile or to have emotional challenges (Buchanan, 1990; Buchanan, Harding, and Mierzwa Hudner). To read a historical summary article on this research discovery, please click here.