Occupation and the risk of bothersome tinnitus: results from a prospective cohort study (HUNT)

OBJECTIVES: Estimates of occupation-specific tinnitus prevalence may help identify high-risk occupations where interventions are warranted. The authors studied the effect of occupation on prevalence of bothersome tinnitus and estimated the attributable fraction due to occupation. The authors also studied how much of the effect remained after adjusting for noise exposure, education income, hearing thresholds and other risk factors. DESIGN: A prospective cohort study. SETTING: A health survey of the Nord-Trøndelag county of Norway. PARTICIPANTS: A sample of the general adult population (n=49 948). PRIMARY OUTCOME MEASURE: The primary outcome measure is bothersome tinnitus. RESULTS: Occupation had a marked effect on tinnitus prevalence. The effect of occupation on tinnitus was reduced in men by controlling for self-reported occupational noise exposure and in women by controlling for education and income. Adding hearing loss as a predictor increased the effect of occupation somewhat. In men, age-adjusted prevalence ratios of tinnitus ranged from 1.5 (workshop mechanics) to 2.1 (crane and hoist operators) in the 10 occupations with highest tinnitus prevalence. In women, the most important contribution to the tinnitus prevalence was from the large group of occupationally inactive persons, with a prevalence ratio of 1.5. CONCLUSION: This study found a moderate association between occupation and bothersome tinnitus.