In order to clarify the characteristics of the severe Meniere's disease we analyzed various epidemiological factors, such as sex ratio, duration of illness, etc., in a series of 958 patients with a definite Meniere's disease. The data were obtained from the three Japan-wide surveys of Meniere's disease conducted by the Meniere's Disease Research Committee of Japan (1975-76) and the Vestibular Disorders Research Committee of Japan (1982-84 & 1990). All subjects were classified into two groups : severe and non-severe. The former contained patients with bilateral and unilateral disease. Those with unilateral severe disease had suffered from markedly disabling attacks of paroxysmal vertigo for more than 3 years.
1) There were 95 patients with bilateral disease, 238 with unilateral severe disease and 625 with non-severe vertigo. About 40% of the subjects had severe disease.
2) Over half of the patients with definite Meniere's disease were females. (bilateral disease 64% ; unilateral severe disease 52% ; non-severe disease 53%)
3) The average duration of illness in the severe group (bilateral, 7.1 years ; unilateral, 8.5 years) was longer than that in the non-severe group (3.3 years).
4) The incidence of otitis media in the past history was higher in the unilateral severe group than in non-severe group.
5) Changes in the atmospheric pressure and in the emotional state were more likely to trigger vertigo attacks in the severe group than in the non-severe group.