Occupational noise-induced hearing loss reports and tinnitus in Finland

Conclusion. In occupational noise-induced hearing loss (NIHL) reports, many tinnitus sufferers probably remain undetected and untreated at present. Attention should be focused on tinnitus, as well as threshold shifts resulting from NIHL. Objectives. Occupational NIHL is frequent among workers in industrialized countries and it is one of the greatest occupational health hazards. Hearing conservation programs have led to a reduction in the numbers of severe occupational NIHL. Our objectives were to analyze the severity of occupational NIHL reported in Finland, identify risk occupations, and investigate the occurrence of tinnitus among the reported cases. Materials and methods. We examined the records of 857 NIHL cases with an identifiable disability category of the total 858 NIHL cases reported in 2000. We sent tinnitus questionnaires to 366 of these NIHL cases. Results. The degree of speech-frequency hearing loss was generally low, and a mention of tinnitus was reported in only 34 cases (4.0%). However, 88.7% of the patients actually had unreported tinnitus.