Prevalence of hearing loss among 18-year-old Swedish men during the period 1971-1995.
OBJECTIVE
To study the hearing of 18-year-old men by using screening audiograms obtained at military conscription.


METHODS
The study group comprised 301,873 Swedish men belonging to six age cohorts born from 1953 to 1977 who had been screened at age 18 years from 1971 to 1995. The prevalence of mild to moderate hearing loss was investigated.


RESULTS
Of the entire study group, 13.1% had elevation of one or more pure tone thresholds. In most cases, 11.9%, the elevation was situated in the high-frequency region. High-frequency hearing loss was more common in the left ear (7.5%) than in the right ear (6.2%). The prevalence of hearing loss decreased during the period 1971 to 1981 from 15.7% to 8.3%. During the last part of the study period, 1986 to 1995, the prevalence increased from 9.8% to 16.3%. The increase included mild to moderate degrees of hearing loss with thresholds below 35 dB HL. The prevalence of threshold elevations was highest in sparsely populated areas of Sweden and lowest in large, metropolitan areas of Sweden from 1971 to 1986. During the last part of the study period the geographical differences decreased or disappeared.


CONCLUSIONS
The total prevalence of hearing loss was in accordance with other reports. The frequency 6 kHz was most affected by threshold elevations. The prevalence of hearing loss decreased in the first part of the study period, and increased at the end of the study period. Hearing loss was most commonly seen in rural areas.
Muhr
Per
P
Department of Clinical Neuroscience, Karolinska Institute and Department of Audiology, Karolinska University Hospital, Stockholm, Sweden. per.muhr@mil.se
Rasmussen
Finn
F
Rosenhall
Ulf
U
D000293:Adolescent; D001299:Audiometry; D015331:Cohort Studies; D034381:Hearing Loss / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008403:Mass Screening; D008887:Military Medicine; D015995:Prevalence; D012042:Registries; D012424:Rural Population; D014505:Urban Population