PP1407 - Investigating the Role of Diet and Nutrition in the Etiology of Tinnitus

Tinnitus occurs when an individual perceives sound (e.g., ringing, buzzing, hissing) without an external source. Aging and noise exposure are well-known risk-factors for chronic tinnitus, but they are not perfectly predictive; not all people who experience tinnitus are older nor do they have noise-induced hearing loss. Prior research indicates that patients of all ages with chronic tinnitus tend to have Vitamin B12 and folate deficiencies, as well as nitrate abundances. This study aims to evaluate if diet and vitamin supplement intake is related to young adults experiencing chronic tinnitus and start a conversation surrounding the value of audiological risk profiling.  


Summary:

The purpose of the current study is to investigate if diet and vitamin supplement intake is related to a young adult experiencing chronic tinnitus. Prior research indicates that patients of all ages with chronic tinnitus tend to have Vitamin B12 and folate deficiencies, as well as nitrate abundances. B-12 and folate deficiencies are linked to demyelination, degeneration of the axons, and resulting nerve death. Demyelination of auditory nerve fibers and the sequential distortion of the resting state of spontaneous nerve fibers is a pathophysiology of tinnitus. Additionally, associations have been found between high urinary levels of nitrate and hearing loss. Successful completion of the present project will help identify nutritive patterns in the diets of individuals who experience chronic tinnitus. 

The Diet History Questionnaire III (DHQIII) is a food frequency questionnaire created by the National Institutes of Health (NIH) based on dietary recall data from the National Health and Nutrition Examination Surveys (NHANES). The DHQIII survey was sent to young adults aged 18-35 years identified as having chronic tinnitus (CT) or no tinnitus (NT). CT was defined as self-reported tinnitus perception (i.e., ringing in ears/head) for over 1 year. NT was defined as no report of tinnitus. The study’s participants were first recruited for an ongoing NIH R21 study in the lab investigating genetic susceptibility to tinnitus in young adults. 24 participants with CT (NFemales = 14) and 24 matched controls (NFemales = 14) participated in the present study. Subjects were controlled for age, sex, and noise exposure background (NEB). Individuals with hearing loss, evidenced by a pure tone average of greater than 25 dB, and/or active middle ear dysfunction, evidenced by otoscopy or tympanometry, and other documented otologic pathologies were excluded. Both CT and NT subjects took the same survey.  

We evaluated the relationships between nutrient intake and tinnitus experience through a multivariate regression analysis. The independent categorical variable was tinnitus status, or whether the participant had chronic tinnitus or not. The dependent ratio variable(s) were the nutrients that the DHQIII study was measuring. A two-sample t test was run to assess differences between the mean intakes of nutrients and vitamins between the CT and NT groups. There was a significant relationship (p < .05) between a person having chronic tinnitus and consuming cured meat protein (0.021), thus increasing their nitrate levels. Without molecular study, causality cannot be inferred, but there is a suggestive association between cured meat protein/nitrate intake and tinnitus. The relationship between chronic tinnitus (CT) and Vitamin B12 intake approached significance (p=.051), as there was a trend that those with lower levels of B12 also had chronic tinnitus. The power of the statistical analysis is determined in large part by the number of subjects who have participated in the study. Prior to February 2023, I plan to recruit at least 10-15 more subjects to strengthen our results. As a student clinician, studying risk profiling for tinnitus is a way that I can assess prevention for audiological pathologies, and help encourage prophylactic measures in our field.