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Person OC, Puga ME, da Silva EM, et al. Zinc supplementation for tinnitus. Cochrane Database Syst Rev. 2016;11:CD009832doi: 10.1002/14651858.CD009832.pub2.
Person, O. C., Puga, M. E., da Silva, E. M., & Torloni, M. R. (2016). Zinc supplementation for tinnitus. The Cochrane database of systematic reviews, 11CD009832. https://doi.org/10.1002/14651858.CD009832.pub2
Person, Osmar C, et al. "Zinc supplementation for tinnitus." The Cochrane database of systematic reviews vol. 11 (2016): CD009832. doi: https://doi.org/10.1002/14651858.CD009832.pub2
Person OC, Puga ME, da Silva EM, Torloni MR. Zinc supplementation for tinnitus. Cochrane Database Syst Rev. 2016 Nov 23;11:CD009832. doi: 10.1002/14651858.CD009832.pub2. PMID: 27879981; PMCID: PMC6464312.
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Cochrane Database Syst Rev. 2016 Nov 23;11:CD009832. doi: 10.1002/14651858.CD009832.pub2.

Zinc supplementation for tinnitus.

The Cochrane database of systematic reviews

Osmar C Person, Maria Es Puga, Edina Mk da Silva, Maria R Torloni

Affiliations

  1. Medicina, Medical School, Universidade Federal de São Paulo, Rua Pedro de Toledo, 598, São Paulo, São Paulo, Brazil, 04039-001.

PMID: 27879981 PMCID: PMC6464312 DOI: 10.1002/14651858.CD009832.pub2

Abstract

BACKGROUND: Tinnitus is the perception of sound without external acoustic stimuli. Patients with severe tinnitus may have physical and psychological complaints and their tinnitus can cause deterioration in their quality of life. At present no specific therapy for tinnitus has been found to be satisfactory in all patients. In recent decades, a number of reports have suggested that oral zinc supplementation may be effective in the management of tinnitus. Since zinc has a role in cochlear physiology and in the synapses of the auditory system, there is a plausible mechanism of action for this treatment.

OBJECTIVES: To evaluate the effectiveness and safety of oral zinc supplementation in the management of patients with tinnitus.

SEARCH METHODS: The Cochrane ENT Information Specialist searched the ENT Trials Register; Central Register of Controlled Trials (CENTRAL 2016, Issue 6); PubMed; EMBASE; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 14 July 2016.

SELECTION CRITERIA: Randomised controlled trials comparing zinc supplementation versus placebo in adults (18 years and over) with tinnitus.

DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures recommended by Cochrane. Our primary outcome measures were improvement in tinnitus severity and disability, measured by a validated tinnitus-specific questionnaire, and adverse effects. Secondary outcomes were quality of life, change in socioeconomic impact associated with work, change in anxiety and depression disorders, change in psychoacoustic parameters, change in tinnitus loudness, change in overall severity of tinnitus and change in thresholds on pure tone audiometry. We used GRADE to assess the quality of the evidence for each outcome; this is indicated in italics.

MAIN RESULTS: We included three trials involving a total of 209 participants. The studies were at moderate to high risk of bias. All included studies had differences in participant selection criteria, length of follow-up and outcome measurement, precluding a meta-analysis. The participants were all adults over 18 years with subjective tinnitus, but one study conducted in 2013 (n = 109) included only elderly patients. Improvement in tinnitus severity and disabilityOnly the study in elderly patients used a validated instrument (Tinnitus Handicap Questionnaire) for this primary outcome. The authors of this cross-over study did not report the results of the two phases separately and found no significant differences in the proportion of patients reporting tinnitus improvement at four months of follow-up: 5% (5/93) versus 2% (2/94) in the zinc and placebo groups, respectively (risk ratio (RR) 2.53, 95% confidence interval (CI) 0.50 to 12.70; very low-quality evidence).None of the included studies reported any significant adverse effects. Secondary outcomesFor the secondary outcome change in tinnitus loudness, one study reported no significant difference between the zinc and placebo groups after eight weeks: mean difference in tinnitus loudness -9.71 dB (95% CI -25.53 to 6.11; very low-quality evidence). Another study also measured tinnitus loudness but used a 0- to 100-point scale. The authors of this second study reported no significant difference between the zinc and placebo groups after four months: mean difference in tinnitus loudness rating scores 0.50 (95% CI -5.08 to 6.08; very low-quality evidence).Two studies used unvalidated instruments to assess tinnitus severity. One (with 50 participants) reported the severity of tinnitus using a non-validated scale (0 to 7 points) and found no significant difference in subjective tinnitus scores between the zinc and placebo groups at the end of eight weeks of follow-up (mean difference (MD) -1.41, 95% CI -2.97 to 0.15; very low-quality evidence). A third trial (n = 50) also evaluated the improvement of tinnitus using a non-validated instrument (a 0 to 10 scale: 10 = severe and unbearable tinnitus). In this study, after eight weeks there was no difference in the proportion of patients with improvement in their tinnitus, 8.7% (2/23) treated with zinc versus 8% (2/25) of those who received a placebo (RR 1.09, 95% CI 0.17 to 7.10, very low-quality evidence).None of the included studies reported any of our other secondary outcomes (quality of life, change in socioeconomic impact associated with work, change in anxiety and depression disorders, change in psychoacoustic parameters or change in thresholds on pure tone audiometry).

AUTHORS' CONCLUSIONS: We found no evidence that the use of oral zinc supplementation improves symptoms in adults with tinnitus.

References

  1. Trends Neurosci. 1999 Feb;22(2):74-80 - PubMed
  2. Laryngoscope. 1999 Aug;109(8):1202-11 - PubMed
  3. J Comp Neurol. 1999 Oct 11;413(1):101-12 - PubMed
  4. J Acoust Soc Am. 1998 Oct;104(4):2314-25 - PubMed
  5. J Am Acad Audiol. 2000 Mar;11(3):115-24 - PubMed
  6. J Nutr. 2000 May;130(5S Suppl):1471S-83S - PubMed
  7. Hear Res. 2001 Feb;152(1-2):43-54 - PubMed
  8. Hear Res. 2001 Aug;158(1-2):95-101 - PubMed
  9. Brain. 2002 Mar;125(Pt 3):524-37 - PubMed
  10. Int J Epidemiol. 2002 Feb;31(1):140-9 - PubMed
  11. Auris Nasus Larynx. 2003 Feb;30 Suppl:S25-8 - PubMed
  12. Otol Neurotol. 2003 Jan;24(1):86-9 - PubMed
  13. Int J Audiol. 2003 Jan;42(1):4-9 - PubMed
  14. J Neurosci. 2003 May 1;23(9):3944-52 - PubMed
  15. Hear Res. 2003 Jun;180(1-2):28-38 - PubMed
  16. Brain. 2003 Oct;126(Pt 10):2235-45 - PubMed
  17. J Neurochem. 1992 Jul;59(1):93-8 - PubMed
  18. Trends Neurosci. 2004 Nov;27(11):676-82 - PubMed
  19. J Neurosci. 2005 Jan 19;25(3):699-705 - PubMed
  20. PLoS Med. 2005 Jun;2(6):e153 - PubMed
  21. Psychosom Med. 2005 Sep-Oct;67(5):833-8 - PubMed
  22. J Speech Lang Hear Res. 2005 Oct;48(5):1204-35 - PubMed
  23. Eur J Neurosci. 2006 Jun;23(11):3124-38 - PubMed
  24. Hear Res. 2006 Nov;221(1-2):59-64 - PubMed
  25. Hear Res. 2006 Dec;222(1-2):1-15 - PubMed
  26. Arch Otolaryngol Head Neck Surg. 2006 Dec;132(12):1323-30 - PubMed
  27. Prog Brain Res. 2007;166:227-33 - PubMed
  28. Int Tinnitus J. 2008;14(1):69-72 - PubMed
  29. Trends Amplif. 2008 Sep;12(3):170-87 - PubMed
  30. Ann Otol Rhinol Laryngol. 1991 Aug;100(8):647-9 - PubMed
  31. Brain. 2009 Feb;132(Pt 2):524-36 - PubMed
  32. Hear Res. 2009 Jul;253(1-2):15-31 - PubMed
  33. J Clin Neurol. 2009 Mar;5(1):11-9 - PubMed
  34. Noise Health. 2009 Jul-Sep;11(44):156-60 - PubMed
  35. J Speech Hear Res. 1991 Feb;34(1):197-201 - PubMed
  36. Cochrane Database Syst Rev. 2010 Mar 17;(3):CD007330 - PubMed
  37. Brain Res. 2010 Jun 25;1342:24-32 - PubMed
  38. Neuron. 2010 Jun 24;66(6):819-26 - PubMed
  39. J Neurosci. 2010 Jul 14;30(28):9578-87 - PubMed
  40. Int J Otolaryngol. 2010;2010:265861 - PubMed
  41. Ear Hear. 1990 Dec;11(6):434-45 - PubMed
  42. Cochrane Database Syst Rev. 2010 Sep 08;(9):CD005233 - PubMed
  43. J Neurosci. 2010 Nov 10;30(45):14972-9 - PubMed
  44. Neurosci Biobehav Rev. 2011 Apr;35(5):1089-109 - PubMed
  45. Eval Health Prof. 2011 Dec;34(4):413-20 - PubMed
  46. Nature. 2011 Feb 3;470(7332):101-4 - PubMed
  47. Proc Natl Acad Sci U S A. 2011 May 3;108(18):7601-6 - PubMed
  48. Laryngoscope. 2011 Jul;121(7):1555-64 - PubMed
  49. J Eval Clin Pract. 2011 Aug;17(4):684-92 - PubMed
  50. Neurosci Res. 1990 Aug;8(4):221-54 - PubMed
  51. J Neurosci. 2011 Sep 21;31(38):13452-7 - PubMed
  52. BMC Health Serv Res. 2011 Nov 04;11:302 - PubMed
  53. Ugeskr Laeger. 1990 Aug 27;152(35):2473-5 - PubMed
  54. Hear Res. 2012 Jan;283(1-2):98-106 - PubMed
  55. Ear Hear. 2012 Mar-Apr;33(2):153-76 - PubMed
  56. Restor Neurol Neurosci. 2012;30(2):137-59 - PubMed
  57. Hear Res. 2013 Jan;295:79-86 - PubMed
  58. Front Syst Neurosci. 2012 May 08;6:31 - PubMed
  59. Lancet. 2012 May 26;379(9830):1951-9 - PubMed
  60. Cochrane Database Syst Rev. 2012 Nov 14;11:CD006371 - PubMed
  61. Otol Neurotol. 2013 Aug;34(6):1146-54 - PubMed
  62. Cochrane Database Syst Rev. 2014 Jan 31;(1):CD010151 - PubMed
  63. Br J Clin Psychol. 1988 Sep;27 ( Pt 3):213-22 - PubMed
  64. Behav Neurosci. 1988 Dec;102(6):811-22 - PubMed
  65. Am J Otol. 1986 Nov;7(6):476-7 - PubMed
  66. Arch Otorhinolaryngol. 1987;244(3):190-3 - PubMed
  67. Am J Otol. 1985 Jan;6(1):116-7 - PubMed
  68. Arch Otolaryngol Head Neck Surg. 1996 Feb;122(2):143-8 - PubMed
  69. Nihon Jibiinkoka Gakkai Kaiho. 1997 Sep;100(9):915-9 - PubMed
  70. Proc Natl Acad Sci U S A. 1998 Aug 18;95(17):10340-3 - PubMed
  71. Hear Res. 1998 Nov;125(1-2):98-108 - PubMed

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