(Source: National Institute of Health)
Adults who are HIV-positive are more likely to experience hearing loss than adults who do not have HIV, according to research published online December 26 in JAMA-Otolaryngology-Head & Neck Surgery. Researchers report that adults with HIV were more likely to experience difficulty hearing both high and low tones, regardless of the severity of HIV disease progression or the use of and adherence to HIV medications. Funded by the National Institutes of Health (NIH), the new findings expand upon earlier research that has suggested an increased risk of hearing loss in adults with HIV.
Other studies have found that children who were exposed to HIV in the womb are at increased risk of hearing loss by age 16. In addition, earlier studies in adults have linked hearing loss at both high and low frequencies with diabetes, suggesting a possible connection with hearing loss and chronic, systemic diseases.
Peter Torre, a hearing scientist who specializes in epidemiology at San Diego State University, was the lead author of the current study and the earlier NIH-supported study on children. Collaborators on the new study include colleagues from the NIH’s National Institute on Deafness and Other Communication Disorders (NIDCD), the lead funder of the study, as well as from Johns Hopkins University and Georgetown University.
The researchers recruited HIV-positive and HIV-negative participants from two long-standing, HIV cohort studies in the U.S. funded by other NIH institutes: middle-aged men (mean age 57.1 years) from the Baltimore-Washington, D.C., site of the Multicenter AIDS Cohort Study (MACS), which began in 1984, and middle-aged women (mean age 47.7 years) from the Washington, D.C., site of the Women’s Interagency HIV Study (WIHS), which began in 1994. A total of 397 adults—262 men, of whom 117 were HIV-positive, and 134 women, of whom 105 were HIV-positive—participated in the study.
Each participant had a standard clinical hearing test at a university-based audiology clinic to determine whether participants could hear a variety of tones ranging from 250 to 8000 hertz at different volume thresholds. Participants also completed a hearing-related questionnaire developed from the NIDCD-funded adult Hearing Supplement to the 2007 National Health Interview Survey. Researchers collected data on participants’ history of taking and adherence to HIV treatments to determine if the medications contributed to the hearing loss; they also measured participants’ white blood cell count and viral load (the amount of HIV in the blood) to determine the severity of disease progression.
The HIV-positive men and women had trouble hearing both the low tones and the high tones, the researchers report. On average, their threshold for hearing the tones was about 10 decibels higher than the HIV-negative men and women.
Although experiencing hearing loss at higher frequencies is common among middle-aged adults in general, men and women with HIV in the study also experienced a decrease in their ability to hear lower frequencies, regardless of the use of HIV medications or the severity of disease progression. These results are similar to findings from other studies, which showed an association between other chronic diseases, including diabetes, with hearing loss at both high and low frequencies. The inability to hear at lower frequencies can impact a person’s ability to distinguish vowel sounds and some consonant sounds, making communication and word recognition difficult. Hearing loss can compromise the social, emotional, educational, and vocational aspects of a person’s life.
“Given the pattern of hearing loss among middle-aged, HIV-positive men and women, and adults with diabetes, it appears that chronic conditions like HIV and diabetes in and of themselves have a systemic effect that impacts hearing loss,” said Howard Hoffman, an NIDCD epidemiologist and a co-author of the study. “The underlying mechanisms of that hearing loss are not clearly understood, and we plan to look at that relationship in future studies.”
This study was funded by the NIDCD and the National Institute of Allergy and Infectious Diseases (NIAID) through cooperative agreements U01-A1-035042-18 (MACS) and U01-A1-03499-17 (WIHS). Support of the Baltimore-Washington, D.C., MACS site was provided by the NIAID, with supplemental funding from the National Cancer Institute (U01-A1-35042). Support of the Metropolitan Washington, D.C., WIHS site was provided by the NIAID (U01-A1-34994) and by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (U01-HD-32632).