A mortality study of patients with Itai-itai disease.

A follow-up study was carried out from April 1967 to October 1982 on 117 patients with Itai-itai disease and 117 controls matched for age, sex, and residential area. The number of deaths during this period was significantly higher in the patients with Itai-itai disease (85, 72.6%) than in the controls (59, 50.4%). Comparison of the annual data from 1968 to 1982 showed that the number of deaths was significantly larger in the patient group. The mean survival time in years up to October 1982 was 76.4 in the patient group and 78.3 in the control group; the difference is statistically significant. These results show a long-lasting influence of Itai-itai disease on the prognosis of the patients.