A study on the epidemiology of tinnitus in the United Kingdom

Date of ISAC Approval: 
01/08/2018
Lay Summary: 
Tinnitus is a common symptom with variable manifestations. Patients suffering from tinnitus experience the symptom as a perception of sound in the absence of an external source. It may be described as ringing, buzzing, clicking or roaring; it can be persistent, bothersome, and may substantially affect the quality of life. The cause of suffering is not clearly understood nor does an effective medical therapy exist. A study with CPRD data showed that there are around 5 cases per 10,000 persons per year with a new diagnosis of severe tinnitus. An economic evaluation of tinnitus associated costs estimated an annual healthcare burden of £750 million for the NHS. More research is required to gain a deeper understanding of the disease and a better characterization of affected patients. With this study we will focus on tinnitus patients recorded by general practitioners in the CPRD to provide further information on demography, lifestyle factors and comorbidities in tinnitus patients compared to persons without tinnitus.
Technical Summary: 
We will conduct a cohort analysis to determine incidence rates of first-time diagnosed tinnitus in the CPRD population between 2000 and 2016. We will then study various characteristics of tinnitus cases and compare them to a sample of tinnitus-free patients using a case-control design. For this purpose we will identify a matched control group of patients without tinnitus. We will assess demographic data, lifestyle factors, as well as associated comorbidities in tinnitus cases and controls and evaluate whether these factors are associated with tinnitus, by performing conditional logistic regression analysis.
Health Outcomes to be Measured: 
To assess the incidence rates of tinnitus in adult patients between 2000 and 2016 stratified by age, gender, and year of diagnosis. To describe patient characteristics and the prevalence of comorbidities which have been associated with tinnitus in the literature prior to the onset of the disease, and to compare it to a matched comparison group of control patients without tinnitus.
Collaborators: 

Dr Susan S Jick - Chief Investigator - BCDSP - Boston Collaborative Drug Surveillance Program
Christoph Meier - Collaborator - University of Basel
Daniel Bodmer - Collaborator - University of Basel
Daphne Reinau - Collaborator - University of Basel
Nadja Alexandra Stohler - Corresponding Applicant - University of Basel