Modifiable lifestyle-related risk factors for tinnitus in the general population: An overview of smoking, alcohol, body mass index and caffeine intake

Introduction: Tinnitus is a symptom and not a disease in its own right. A number of medical conditions are known to increase the risk of developing tinnitus. Most known risk factors are otological or neurological, but general health and lifestyle can also precipitate the condition. Understanding these modifiable risk factors can help to identify vulnerable groups and can inform preventive actions to reduce likelihood of developing tinnitus. Smoking, alcohol consumption, body mass index (BMI) and caffeine intake are all lifestyle risk factors hypothesized to be related to tinnitus. Nonetheless, research findings in support of those relationships are somewhat mixed. Methods: A systematic review was conducted to identify all relevant studies on the specific risk factors. Findings were summarized using a narrative synthesis and meta-analysis, where possible. Results: Overall 384 studies were included, mostly using cross-sectional designs. Findings indicated significantly increased risk of tinnitus among current (based on 26 studies) and ever smokers (based on 16 studies) and among obese people (based on seven studies), but no effect of alcohol consumption (based on 11 studies). With respect to caffeine intake or coffee drinking, only three studies examined this risk factor and so we were unable to draw conclusions. Conclusion: Our results contribute to quantifying the relationship between tinnitus and specific lifestyle-related risk factors, and we highlight some of the gaps and inconsistencies across published studies.