Subjective tinnitus is a phantom sound heard only by the affected person and may be a symptom of various diseases. Tinnitus diagnosis and monitoring is based on subjective audiometric and psychometric methods. This review aimed to synthesize evidence for tinnitus presence or its severity. We searched several electronic databases, citation searches of the included primary studies through Web of Science, and further hand searches. At least two authors performed all systematic review steps. Sixty-two records were included and were categorized according the biological variable. Evidence for possible tinnitus biomarkers come from oxidative stress, interleukins, steroids and neurotransmitters categories. We found conflicting evidence for full blood count, vitamins, lipid profile, neurotrophic factors, or inorganic ions. There was no evidence for an association between tinnitus and the remaining categories. The current review evidences that larger studies, with stricter exclusion criteria and powerful harmonized methodological design are needed. Protocol published on PROSPERO (CRD42017070998).

Consumption of high amounts of caffeine has been historically associated with tinnitus worsening. However, recent studies demonstrated that this seems not to be true, and caffeine may even improve tinnitus distress.

To analyze tinnitus features according to caffeine consumption levels.

Case-control study.

Tinnitus patients were compared with patients without tinnitus concerning caffeine consumption. Tinnitus characteristics were correlated to the amount of caffeine consumption among the tinnitus patients.

One hundred and forty two patients with and 140 patients without tinnitus were enrolled. Patients without tinnitus consumed more caffeine than patients with tinnitus (300mL/day versus 100mL/day, P=0.0001). Among the patients with tinnitus, no differences concerning age, gender, tinnitus laterality, periodicity, quality, type of onset, tinnitus matching, hearing loss, THI scores and VAS (volume) according to the amount of caffeine consumed have been found. selleck inhibitor Concerning VAS (distress), the subgroup that consumed less than 150mL of caffeine daily had greater scores (6 versus 5, P=0.048).

Data from this study are on line with more recent studies that were not able to demonstrate any kind of association between high consume of caffeine and tinnitus distress. Moreover, this study was not able to point any possible tinnitus subtype affected by high amounts of caffeine consumption. The higher VAS distress score in the low caffeine consumption subgroup may represent a protective effect of caffeine, which is also on line with other studies.

High amounts of caffeine consumption is not associated with tinnitus and with no tinnitus subgroup, according to tinnitus characteristics. An eventual protective effect of caffeine should be evaluated in further prospective studies.

High amounts of caffeine consumption is not associated with tinnitus and with no tinnitus subgroup, according to tinnitus characteristics. An eventual protective effect of caffeine should be evaluated in further prospective studies.Tinnitus and pain share similarities in their anatomy, pathophysiology, clinical picture and treatments. Based on what is known in the pain field, a heuristic model can be proposed for the pathophysiolgy of tinnitus. This heuristic pathophysiological model suggests that pain and tinnitus are the consequence of an imbalance between two pain/tinnitus evoking pathways, i.e., a lateral sensory pathway and a medial affective pathway, both of which are not balanced anymore by a pain/noise inhibitory pathway. Mechanistically, based on the Bayesian brain concept, it can be explained by a switch occuring under influence of the rostral to dorsal anterior cingulate cortex of its prior predictions, i.e., a reference resetting, in which the pain/tinnitus state is considered as the new reference state. This reference resetting is confirmed by the nucleus accumbens as part of the reward system and maintained by connectivity changes between the nucleus accumbens and the pregenual anterior cingulate cortex. As a consequence it can be suggested to treat pain/tinnitus via reconditioning, either surgically or non-surgically. The model can also be used to develop objective measures for tinnitus and pain via supervised machine learning.The current study examines two different protocols of repetitive transcranial magnetic stimulation (rTMS) targeting three key hubs of cortical tinnitus networks. Patients chose whether they preferred to undergo rTMS treatment for 10 or 20 sessions and were randomized to the different rTMS protocols thereafter. Ninety patients were enrolled in the study with a total dropout rate of 10%. Both rTMS protocols were well tolerated by the patients without any serious adverse events. Overall treatment effects were small both for 2 weeks and 4 weeks of treatment. There was no significant interaction effect between measurement time point and treatment group for neither of the outcome measures nor any differences regarding the applied treatment regimens. The effects of this study contradict former observations suggesting multisite rTMS protocols as promising neuromodulatory strategies. This lack of effect could not be enhanced by increasing the number of treatment sessions in our study.In this study we analyzed psychometric data of 107 individuals who suffer from chronic subjective tinnitus. In particular, we elucidated the relationship between tinnitus-related distress, psychological comorbidities, age, and hearing, and the performance in cognitive concentration and interference tests. Previous research has provided first evidence that individuals with tinnitus may have deficits in cognitive tasks. The present study aimed at extending former research by investigating the relationship between tinnitus distress and cognition. Statistical analyses comprised correlation and regression approaches. We observed a significant relationship between tinnitus distress (tinnitus score, TQ), age and hearing loss and the performance in tests on selective and sustained attention (d2 test) and cognitive interference (Stroop test). Tinnitus distress was identified as the most important predictor of cognitive performance (additionally age for cognitive interference). For other psychometric variables (perceived stress, PSQ; self-efficacy, optimism and pessimism, SWOP) and hearing loss we could not find any meaningful relationship with cognitive performance.