[Mortality of SMON patients in relation to their disabilities]

The relationship between mortality and disability, was studied in SMON patients, who had participated in the questionnaire survey in 1980, by following them for 10 years through municipal resident registration information offices. Eighty deaths were observed among 409 subjects during the follow-up period. The effect of each disability on the mortality of SMON was estimated by applying the Cox proportional hazard model. The presence of severe gait disturbance and low levels of activities of daily living (ADL) were associated with significantly higher risk of death after adjustment for age and sex. The relative risk of visual disturbance was not significant after adjusting for age, sex and other kinds of disability. Those who complained of continuous dysesthesia at the time of the initial survey showed better prognosis than those without such dysesthesia. Among subjects who died during the follow-up period, those who had reported low levels of ADL at the time of the initial survey had a greater proportion of deaths attributable to heart failure and pneumonia than those who had reported high levels of ADL.