UCSD Medical School
UCSD Medical School. Brandon Quester/inewsource

Researchers at UC San Diego School of Medicine released a study Thursday which found hearing loss and high blood sugar are associated with poor cognitive performance among middle-aged and older Latinos.

The study was published Thursday in the online issue of JAMA Otolaryngology-Head & Neck Surgery. In it, the researchers acknowledge a recent connection between hearing loss and Alzheimer’s disease while setting out to analyze the combined relationships between cardiovascular disease risk, hearing loss and cognition.

Latinos are at higher risk than other demographic groups for hearing loss and diabetes, the latter of which is also a risk factor for Alzheimer’s disease and related dementias.

As part of the Hispanic Community Health Study/Study of Latinos, more than 9,000 middle-aged and older Latinos — between the ages of 45 and 74 — underwent hearing examinations, extensive cardiovascular and diabetes testing and cognitive assessments.

Participants include Central Americans, Cubans, Dominicans, Mexicans, Puerto Ricans and South Americans residing in San Diego, Bronx, New York, Chicago and Miami.

Those who displayed hearing loss also included individuals with mild to severe levels of cognitive impairment.

“Initially, we thought that the relationships between hearing loss and cognition would be overshadowed by high cardiovascular disease risk, but this was not the case,” said first author Ariana M. Stickel, a postdoctoral scholar in the Department of Neurosciences at UCSD School of Medicine.

“This opens up promising avenues for interventions to reduce Alzheimer’s disease risk. Evidence suggests that hearing aid use may be protective against cognitive declines for individuals with hearing loss, yet we also see that fewer than 5% of Latinos with hearing loss report using hearing aids. This is something we can change to help prevent cognitive declines, but it is going to take awareness on the part of health care providers and their patients,” Stickel said.

The study also found that high cardiovascular disease risk is associated with poorer cognition.

“We were surprised to find that individuals with high blood sugar and otherwise average cardiovascular health are susceptible to poorer learning and memory, but only if they also had hearing loss,” said senior author Hector Gonzalez, professor in the Department of Neurosciences at UCSD School of Medicine and a member of the UCSD Shiley-Marcos Alzheimer’s Disease Research Center.

Impairments in learning and memory occur in the preclinical stages of Alzheimer’s. Gonzalez said the next step is to investigate what is happening within the brain.

According to a new report by the Lancet Commission, there would be an 8% reduction in dementia prevalence globally if hearing loss alone is eliminated.

“Both hearing loss and diabetes can be modified,” Stickel said. “Latinos are projected to have the highest increase in Alzheimer’s disease and related dementia cases in the U.S. by 2060. Connecting our findings to public health solutions that work for Latinos can help mitigate the impending public health crisis.”

— City News Service