Hearing loss a red flag for Parkinson’s disease

Hearing loss appears to raise the risk of later development of Parkinson’s disease (PD), and this risk may be attenuated by hearing aid use, according to a study.

Researchers used electronic health record data from the US Department of Veterans Affairs. They included 3,596,365 individuals (mean age 67 years, 96 percent) who had an audiogram in the analysis.

Of the participants, 750,010 (20.8 percent) had normal hearing (<20 dB), 1,080,651 (30.0 percent) had mild hearing loss (20 to <35 dB), 1,039,785 (28.9 percent) had moderate hearing loss (35 to <50 dB), 568,296 (15.8 percent) had moderate-to-severe hearing loss (50 to <65 dB), and 157,623 (4.3 percent) had severe-to-profound hearing loss (65-120 dB). Baseline characteristics were balanced across groups.

Over a mean follow-up of 7.6 years, the incidence rate of PD ranged from 3.69 to 11.6 per 10,000 person-years, with rates increasing as the severity of hearing loss increased. At 10 years, the number of additional cases of PD was 6.1 in the mild hearing loss group, 15.8 in the moderate hearing loss group, 16.2 in the moderate-to-severe hearing loss group, and 12.1 in the severe-to-profound hearing loss group in comparison with those who had normal hearing.

When combined with established prodromal conditions, hearing loss was associated with 5.7 additional cases of PD at 10 years compared with either condition alone. However, prompt hearing aid use was associated with a reduction in incident cases of PD by 21.6 cases at 10 years.

The findings highlight the potential of widespread screening for hearing loss and appropriate use of hearing aids in reducing the incidence of PD.