Tinnitus Profiling to Guide Personalized Therapeutic Decisions - Diagnosis Improved with Large-Scale, Longitudinal Data

Tinnitus is a condition characterized by the perception of auditory phantom perceptions without a corresponding external stimulus. Tinnitus can be debilitating despite usually being considered a benign condition, with current estimations that 1% of the population suffers from bothersome tinnitus. Factors such as loudness, laterality, type of perceived sound, loudness fluctuations throughout the day, and ability to concentrate vary between individuals. Additionally, comorbidities such as hyperacusis, detrimental sleep, anxiety, and depression are common complaints among the tinnitus population. Together, those variables highlight how heterogenous tinnitus is, as clinical cases are always composed of a unique mosaic of demographics, tinnitus characteristics, and psychopathological profile.
Researchers and clinicians are increasingly aware of the potential role of heterogeneity in the clinical manifestation of tinnitus. Heterogeneity could explain why only a subset of patients respond to certain clinical treatments available. It would be of great relevance to identify which markers are relevant for individualized interventions. The aim of this doctoral thesis was to advance the understanding of tinnitus heterogeneity towards this goal.
This thesis contains six chapters. In the introduction, a brief overview of tinnitus is given alongside some key concepts that are further articulated in the discussion section; in Chapter 1, I used crowdsensed data from thousands of online users with tinnitus to investigate whether demographics and tinnitus characteristics could predict the outcome of 26 tinnitus-related treatments. In Chapter 2, I investigated the role of personality traits on tinnitus habituation over time. In Chapter III, I researched how often total tinnitus remission takes place in a clinical sample and tried to identify predictors of remission. Additionally, I tried to identify additional predictors of tinnitus habituation, and to map how often comorbidities were experienced by the clinical population, and how often those patients sought tinnitus-related treatments. In chapter IV, I used ecological momentary assessment from users of a mobile app mapping everyday variables related to their tinnitus, like loudness, distress, and concentration to investigate whether those variables were solely state-dependent or whether those states carried over to the following day. This study used state-of-the-art methods to model how those variables interplay with one another at the individual level. Lastly, I discuss current challenges towards untangling tinnitus heterogeneity, and proposals are made to include a quantitative pathopsychological framework to integrate different levels of tinnitus heterogeneity.