Socio-demographic, health, and tinnitus related variables affecting tinnitus severity.

OBJECTIVES: Tinnitus is a highly prevalent symptom with potential severe morbidity. Fortunately, only a small proportion of the population experience problems due to their tinnitus in such a degree that it adversely affects their quality of life (clinically significant tinnitus). It is not known why these individuals develop more burden from tinnitus. It seems likely that the severity of tinnitus can be influenced by different factors, such as socio-demographic or tinnitus characteristics or additional health complaints. It remains unclear from the current literature as to what are the main independent variables that have a bearing on tinnitus severity. This study addresses this problem by investigating variables previously described in the literature as well as additional variables. The aim of this study is to identify socio-demographic, health, and tinnitus variables that independently relate to tinnitus severity the most.

DESIGN: This is a retrospective cohort study performed at the Tinnitus Care Group of the University Medical Center, Utrecht, in 309 consecutively seen chronic tinnitus patients. At this care group, patients are examined according to a structured diagnostic protocol, including history-taking by an otorhinolaryngologist and audiologist, physical examination, and audiometry. Based on results from previous research and theoretical considerations, a subset of data acquired through this diagnostic protocol were selected and used in this study. Univariate and multivariate correlations with tinnitus severity were investigated for 28 socio-demographic, health, and tinnitus variables. Tinnitus severity was measured with the Tinnitus Questionnaire (TQ) and the Tinnitus Handicap Inventory (THI).

RESULTS: Eighteen variables related univariately with the TQ and 16 variables related univariately with the THI. Among these, 14 variables related univariately with both the TQ and the THI. Multivariate analyses showed three variables with an independent significant effect on both the TQ and the THI: percentage of tinnitus awareness during the day, self-reported depression and/or anxiety, and loudness on a Visual Analogue Scale. Three additional variables contributed independently significantly to the explained variance in either the TQ or the THI: level of education, somatic complaints, and tinnitus variability in loudness and/or pitch on a Visual Analogue Scale. These variables were among the first not to reach significance on the other questionnaire.

CONCLUSIONS: Tinnitus severity is shown to be strongly related to percentage of tinnitus awareness during the day, self-reported depression and/or anxiety, subjectively experienced loudness, level of education, existence of additional somatic complaints, and subjectively experienced variability in loudness and/or pitch. Further research is needed to investigate the causal relationship between these variables and tinnitus severity. This knowledge may contribute to a better recognition, follow-up, and/or counseling of more vulnerable patients.