Creutzfeldt-Jakob disease and cadaveric dura mater grafts in Japan: an updated analysis of incubation time.

The incubation time for 76 patients with cadaveric dura mater-transmitted Creutzfeldt-Jakob disease reported in Japan by November 2001 was analyzed to clarify its distributional feature and the risk factors which affect the earlier onset of the disease. Cluster analysis indicated that cases could be divided into 3 clusters with respect to the incubation time, i.e., short (1.4-6.2 years), medium (7.0-11.9 years) and long (12.9-17.6 years). The incubation time in females was significantly shorter than those in males. Patients who were transplanted dura mater for facial spasms had a significantly shorter incubation time than those who received transplantation for other diseases including meningioma, aneurysm, or acoustic schwannoma. These results suggest that some host factors may have an influence on the incubation time of the disease.