Study: vitamin B12 and tinnitus

reference

Singh C, Kawatra R, Guppa J, Awasthi V, Dungana H. Therapeutic role of vitamin B12 In patients with chronic tinnitus: a pilot study. noise health . 2016; 18 (81): 93-97.

draft

double -blind, randomized, placebo -controlled prospective study

participant

The participants were men and women between the ages of 18 and 60 from north India, who have suffered from chronic subjective tinnitus with or without sensorinural hearing loss for more than 6 months. The average age was 38.37 years, the men-to-women ratio 2: 3 and the middle duration of the tinnitus 1.36 years. Tinnitus occurred in 27.5 % of the cases in both ears and in 72.5 % of the cases unilaterally (right ear 32.5 % and left ears 40 %). Participants were excluded if they had one of the following:

• objective (pulsating) tinnitus
• Congeneration anomaly that contributed to
• infection
• Psychiatric illness
• other otological problems than tinnitus
• acute acoustic trauma or chronic noise pollution
• Systemic diseases such as anemia, high blood pressure, diabetes mellitus and hypothyroidism
• Use of medication that is known that you have an effect on tinnitus, such as steroids, cyclendalates and vasodilators, within 4 weeks before the start of your studies
• History of an ear operation, tinnitus status after a head injury or an organic disease in the head and neck area

Intervention

forty patients who met the selection criteria were divided into 2 groups according to the random principle. Group A (n = 20) received 1 ml of intramuscular methylcobalamine (2,500 µg) once a week. Group B (n = 20) received 1 ml of intramuscular isotonic saline as a placebo once a week. Both the patient and the examiner were blinded to the given treatment.

study parameters evaluated

The primary results included re-tone audiometry, tinnitus matching (pitch and volume), vitamin B12 tests before and after treatment by chemiluminescence and a self-report using the tinnitus-index questionnaire. The patients were followed up for 1 month after the procedure and again subjected to all the evaluations mentioned above.

important knowledge

seventeen (42.5 %) of all patients suffering from tinnitus had a vitamin B12 deficiency, with values ​​over 250 pg/ml being considered normal. The prevalence of a vitamin B12 deficiency was 50 % in group A and 35 % in group B. In group A, patients with vitamin B12 deficiency after receiving vitamin B12 injections showed an improvement in the middle tinnitus-heavy index scores ( t = 2.64, p = 0.016 df = 18). Patients in Group A who did not have a vitamin B12 deficiency, as well as patients in group B who received placebo, showed no improvement in their severity index values. The visual analogue scale (VAS) showed that group A patients who had a vitamin B12 deficiency significantly improved with regard to the tinnitus volume after therapy ( t = 2,13, p = 0.04, df = 18). Group B patients showed no significant improvement. Vitamin B12 had no influence on pitch or volume.

Comment

On the basis of newer epidemiological data, up to 600 million adults of tinnitus are affected worldwide, with about 20 % of the cases being classified as serious and weak. from a different neuronal activity in the periphery.

This study tried to determine the therapeutic role of vitamin B12 in the treatment of tinnitus. Vitamin B12 deficiency causes neuropathy in the central nervous system due to hypomethylation. ³ The reduced methylation is based on an inhibition of the methionine synthase (a vitamin B12-dependent enzyme), which causes a lack of S-adenosyl methionine (seed) and thus impairment of the Methylation reactions in the myelin sheath lead. In addition, homocysteine ​​is a neurotoxin and a vascular toxin that is accumulated in vitamin B12 deficiency states, and a connection between the impairment of the homocysteine ​​metabolism in the cochlea and the resulting oxidative stress was found. Vitamin B12 deficiency contributes to tinnitus, in the demyelinization of neurons in the cochlea nerve, with the associated axonal degeneration and ultimately apoptotic neuronal death.

In addition, a vitamin B12 deficiency was associated with the destruction of the microvasculars of the Stria vascularis, which may lead to a decrease in the endocochlear potential, which in turn can lead to tinnitus. ^{5 1993 SHEMesh et al. that subsequent supplementation with vitamin B12 improved its condition. 6 Note that the prevalence of cobalamine deficiency in tinnitus patients in the study by Shemesh et al. Similar to the prevalence in this present study, which was carried out 23 years later.}

The restrictions in the present study is the sample size, which is why it is a pilot study. In addition, the patients came from north India, where vitamin B12 deficiency may be significantly more common compared to the general population in the United States.

It is not surprising that the authors came to the conclusion that Tinnitus could be the only symptom of a vitamin B12 deficiency. While methylcobalamine led to positive effects for tinnitus patients, it is unclear whether other forms of vitamin B12, such as cyanocobalamine, hydroxocobalamine or adenosylcobalamine, would offer similar advantages. Although the study demonstrated the effectiveness of injectable methylcobalamine, it also raises the question of whether high doses of oral, sublingual, transdermalem, intranasal or other administration for methylcobalamine would lead to similar results.

While the authors only suggest the implementation of a serum cobalamine test in patients with chronic tinnitus, it would be advisable to add a complete blood count with differential blood image as well as tests to folate, homocysteine ​​and methylmalone acid levels in serum and in the red blood cells. Vitamin B12 is a safe and promising option in the treatment of tinnitus; However, more studies would be welcomed with larger group sizes.