A Trial of Magnesium Dependent Tinnitus

Study Overview
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Brief Summary
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The purpose of this study was to examine any potential benefit in lessening the severity of tinnitus (ringing or booming sensation in one or both ears) in subjects supplemented with magnesium (532 mg daily).

Detailed Description
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Descriptions of tinnitus date back to the time of ancient Egypt, yet science has failed to unravel the mysterious underlying mechanisms that produce these subjective auditory perceptions of sound. These perceptions may be manifestations of damage resulting from noise exposure, ototoxicity, or other abnormal conditions of the auditory system. However, many individuals have idiopathic tinnitus for which no specific cause can be determined. Although often presenting in conjunction with hearing loss, the magnitude of hearing loss does not necessarily correspond with the severity of tinnitus. In addition, some individuals reporting tinnitus experience concomitant hyperacusis. This relationship suggests these processes may be linked by underlying imbalances at the level of the hair cell. The possible influence of magnesium (Mg) and its antagonist, calcium, has been discussed in the literature as a contributing factor in the mitigation of noise-induced hearing loss, ototoxicity, and the hyperexcitability of the auditory system. Permanent and temporary changes in auditory function have been linked to nutritional deficiencies of magnesium. Mg deficiency has resulted in increased susceptibility to noise-induced hearing loss, ototoxicity, and hyperexcitability of the auditory system. The recommended daily allowance (RDA) for Mg in adults is 4.5 mg/kg; however, all age groups of Americans fall short of the RDA for Mg by 100 mg daily. This lack of appropriate magnesium intake may have negative consequences. For example, the putative Mg mechanism within the auditory system involves a metabolic cellular cascade of events. Specifically, Mg deficiency leads to increased permeability of the calcium channel in the hair cells with a consequent over-influx of calcium, an increased release of glutamate via exocytosis, and overstimulation of N-methyl-D-aspartate receptors on the auditory nerve fibers. Recent studies of both noise-induced hearing loss and idiopathic sensorineural hearing loss have suggested that Mg supplementation may lessen the severity of tinnitus in patients. Mg improved hearing recovery and lessened tinnitus in patients with idiopathic sudden hearing loss. More recently, a well-controlled study that Mg was a relatively safe and convenient adjunct to corticosteroid treatment for enhancing the improvements of hearing in acute-onset sensorineural hearing loss at a dose of 4 g. The protective effect of Mg in noise-induced hearing loss has been previously reported. Despite these encouraging findings, no controlled study has examined the effect of Mg supplementation for subjects with moderate to severe tinnitus. In this study subjects made 4 visits to the clinic over about 2 months. At the first visit, subjects had a hearing test. Prior to beginning each round of supplements, subjects were asked to rate the severity of their tinnitus on a 1-10 scale, and to complete the Tinnitus Handicap Inventory (THI) questionnaire. Subjects were then randomized to 1 of 2 groups. One group began with 532 mg of Mg for 25 days, the other group began with a placebo supplement for 25 days. At visit 2, the subjects had a hearing test, rated their tinnitus, and completed the THI questionnaire as well as the Treatment Period Survey. Subjects did not take any supplement for 2 weeks, then returned for visit 3. At Visit 3, the subjects had a hearing test, rated their tinnitus, and completed the THI questionnaire they then took the opposite supplement (placebo or Mg) for 25 days. At Visit 4, the subjects had a hearing test, rated their tinnitus, and completed the THI questionnaire as well as the Treatment Period Survey.

Official Title
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A Phase III Trial of Magnesium Dependent Tinnitus

Conditions
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Tinnitus

Intervention / Treatment
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* Dietary Supplement: Magnesium
* Other: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Normal Kidney function (last checked within 6 months). Serum creatinine levels 1.5 mg/dL or below for females, 2.0 mg/dL for males. An audiogram within the past 6 months Mayo Clinic patients who live in Phoenix area Exclusion criteria: Any participant with decreased kidney function within past 6 months, over 1.5 mg/dL for females and over 2.0 mg/dL for males. Current treatment with Lithium Tinnitus rating with 0, 1, or 2 on the 0-10 Tinnitus scale

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Magnesium first, then placebo<br>Magnesium 532 mg daily for 25 days followed by 2 weeks of washout followed by 25 days of placebo. | Dietary Supplement: Magnesium<br>* Magnesium 532 mg a day<br>Other: Placebo<br>* matching form/dosage<br>|
| Placebo Comparator: Placebo first, then magnesium<br>Placebo daily for 25 days followed by 2 weeks of washout followed by magnesium 532 mg daily for 25 days. | Dietary Supplement: Magnesium<br>* Magnesium 532 mg a day<br>Other: Placebo<br>* matching form/dosage<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Tinnitus Distress Rating | This is a single-item patient-reported distress rating on a 0-10 scale, with 0=no tinnitus to 10=worst possible tinnitus. | Pre-treatment, Post-treatment, up to four weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Comparison of Average Tinnitus Handicap Inventory (THI) Across All Subjects | The Tinnitus Handicap Inventory measures the extent that tinnitus interferes with daily activities and sleep.The questionnaire consists of 25 questions, the score can range from 0 (slight problem) to 100 (catastrophic). The score can be converted to a categorical variable as follows: 0-16=Slight; 18-36=Mild; 38-56=Moderate; 58-76=Severe; 78-100=Catastrophic. | Pre-treatment, Post-treatment, up to four weeks | 
| Comparison of Average Tinnitus Handicap Inventory (THI) Across All Men | The Tinnitus Handicap Inventory measures the extent that tinnitus interferes with daily activities and sleep.The questionnaire consists of 25 questions, the score can range from 0 (slight problem) to 100 (catastrophic). The score can be converted to a categorical variable as follows: 0-16=Slight; 18-36=Mild; 38-56=Moderate; 58-76=Severe; 78-100=Catastrophic. | Pre-treatment, Post-treatment, up to four weeks | 
| Comparison of Average Tinnitus Handicap Inventory (THI) Across All Women | The Tinnitus Handicap Inventory measures the extent that tinnitus interferes with daily activities and sleep.The questionnaire consists of 25 questions, the score can range from 0 (slight problem) to 100 (catastrophic). The score can be converted to a categorical variable as follows: 0-16=Slight; 18-36=Mild; 38-56=Moderate; 58-76=Severe; 78-100=Catastrophic. | Pre-treatment, Post-treatment, up to four weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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hearing, magnesium