New York, Sep 20 (IANS): The rate of hearing loss increases significantly after age 90 even though the use of a hearing aid remains underused by this group, say researchers, including one of Indian-origin.

"There is urgency to increase hearing aid use among the older population because untreated hearing loss is associated with higher risks for social isolation, depression, dementia, inability to work, reduced physical activity, and falls," said Anil K. Lalwani of the Columbia University College of Physicians and Surgeons in New York and his colleagues.

In the study published online in the journal JAMA Otolaryngology-Head & Neck Surgery, the researchers examined if the rate of age-related hearing loss is constant in the older old - 80 years and older.

Presbycusis, or age-related hearing loss (ARHL), affects approximately two-thirds of adults older than 70 years and four-fifths of adults older than 85.

The majority of research in ARHL, however, groups participants older than 70 years into a single category, thus obscuring changes in the severity of hearing loss as individuals live to 80 years or older.

This study included 647 patients 80 to 106 years of age who had audiometric evaluations at an academic medical centre.

The degree of hearing loss was compared across the following age brackets -- 80 to 84 years, 85 to 89 years, 90 to 94 years, and 95 years and older.

The researchers found that changes in hearing among age brackets were higher during the 10th decade of life than the 9th decade at all frequencies for all the patients.

Correspondingly, the annual rate of low-frequency hearing loss was faster during the 10th decade.

Despite the universal presence of hearing loss in this sample, 382 patients (59 percent) used hearing aids, the findings showed.