Dietary Supplement Comprised of β-Carotene, Vitamin C, Vitamin E, and Magnesium: Failure to Prevent Music-Induced Temporary Threshold Shift

Abstract

This study examined potential prevention of music-induced temporary threshold shift (TTS) in normal-hearing participants. A dietary supplement composed of β-carotene, vitamins C and E, and magnesium was assessed using a randomized, placebo-controlled, double-blind study design. Dosing began 3 days prior to the music exposure with the final dose consumed approximately 30-min pre-exposure. Post-exposure TTS was measured, with no significant difference as a function of treatment. Distortion product otoacoustic emission amplitudes were suppressed after music exposure in both groups, with no significant difference as a function of treatment. Tinnitus was more likely to be reported by the treatment group, but there were no group differences in perceived loudness or bothersomeness. Taken together, this supplement had no effect on noise-induced changes in hearing. Recommendations for future clinical trials are discussed.

Effects of Recreational Noise on Threshold and Suprathreshold Measures of Auditory Function

“…These differences replicate those reported for several other cohorts of normal hearing young adults, with men having slightly poorer hearing at a small number of frequencies across cohorts. [46][47][48] The relationship between threshold at 4,000 Hz and noise exposure score (L Aeq8760 ) was evaluated for men (Figs. 3A, 3B) and women (Figs.…”

Otoprotectants: From Research to Clinical Application

“…A complete discussion of the drug development pathway for ebselen can be found in the review by Lynch et al 30 Taken together, the preliminary data are promising, and additional research will be important in determining not only the repeatability and reliability of the observed protection against TTS in humans but also the specific patient populations who have the potential to benefit. Whether the current observations of protection against the moderate TTS induced in this clinical trial paradigm (i.e., ranging from 0 to 20 dB TTS 15 minutes postexposure, with largely complete recovery typically observed within 3 hours 29,31,32 ) will extend to protection against larger acoustic traumas remains to be determined, and PTS is also a question of interest for future studies. These latter studies are a challenge for all agents of interest, as these studies are much more difficult to design and complete for a variety of reasons (outlined in the "Research Needs" section).…”

“…In NCT00808470, an experimental tablet-based dosing paradigm did not reduce or prevent TTS or noise-induced tinnitus. 32 In the other, earlier study completed in a partnership with members of the Karolinska Institute (see "Disclosure" section), potential prevention of TTS in soldiers completing weapons training was assessed, but no reliable TTS occurred in either the placebo or treatment group, which consumed an experimental capsule-based treatment. 42 Several studies have assessed potential prevention of DIHL in human patients, with little or no evidence of benefit in most studies.…”

“…In these kinds of field studies, smaller-than-expected changes in hearing may be a consequence of the improved use of HPDs while participating in the clinical trial. However, even in controlled laboratory studies during which a calibrated sound exposure is delivered directly, clinical trial participants have on average had smaller changes in hearing 29,32 than participants in preliminary studies tested as part of the development of the clinical trial methodology. 31 Another approach that is less likely to be confounded by variable HPD use, but which perhaps has increased real-world relevance, is the recruitment of participants who attended real-world music events where HPD use is not mandatory.…”

Do dietary factors significantly influence tinnitus?

“…25,26 Randomised, double-blinded, placebocontrolled trials also failed to show any effects on the use of antioxidant agents for tinnitus management (eg vitamins C and E, β-carotene, α-lipoic acid). 27,28 Nonetheless, after medications (45%) and hearing aids (9%), dietary supplements (8%) are one of the most widely discussed interventions in tinnitus management with physicians, as shown by a cross-sectional analysis of the representative 2007 National Health Interview Survey. 29 As a result of the clear research data, the American Academy of Otolaryngology -Head and Neck Surgery Foundation contains the following evidence-based statement in its clinical practice guideline: 'Clinicians should not recommend Ginkgo biloba, melatonin, zinc, or other dietary supplements for treating patients with persistent, bothersome tinnitus'.…”