Effects of non-pharmacological interventions on insomnia in patients with tinnitus: a systematic review & meta-analysis.

Introduction Tinnitus is the perception of sound (ringing or buzzing) in the absence of external/electrical stimulation. It affects about 10% of people in the United Kingdom, with rates of comorbid sleep problems ranging from 50 to 77%. Our aim was to systematically review the literature relating to the effectiveness of cognitive behavioural therapy (CBT) interventions on insomnia in patients with tinnitus. Methods A systematic literature search of seven scientific databases (Cochrane Library/CENTRAL, PROSPERO, HTA/DARE, Medline, CINAHL, Web of science, ClinicalTrials.gov) was performed, covering literature published up to August 2018. Database searching was supplemented with internet searching and forward/backward citation tracking from systematic reviews and included studies. Studies were considered eligible for inclusion if they involved: adult patients (living at home or in a care setting) with tinnitus; CBT interventions for tinnitus and/or insomnia; any comparator (i.e. usual care, alternative intervention); randomised controlled trials or quasi-randomised controlled trials that reported sleep outcomes. The primary outcome was a mean difference in sleep. The quality of the included studies was assessed according to the Cochrane Risk of Bias assessment tool. Two reviewers independently reviewed title/abstracts initially and then full-text papers, before proceeding with data extractions. Any discrepancies were resolved through discussion, or where required a third reviewer. Results Four studies (427 participants) were included in the meta-analysis. The majority of the interventions were internet-based and targeted tinnitus distress with insomnia reported as a secondary outcome. Sleep management and/or guidance was an additional optional module in three studies. Results demonstrated a significant reduction in insomnia as measured by the insomnia severity index [-3.28; 95% CI=-4.51,-2.05; I2=0%]), which equates to a moderate effect size (0.05). Risk of bias was considered low in all categories except blinding (participants and personnel and/or outcome assessment), which was not always possible due to study design. Conclusion This systematic review and meta-analysis showed that CBT-based interventions can improve insomnia in people diagnosed with tinnitus. Further research into interventions specifically targeting sleep problems would be advantageous, especially exploring which components of CBT are the most effective for alleviating sleep problems in patients with tinnitus