Factors influencing the survival period in Japanese patients with sporadic Creutzfeldt–Jakob disease

Abstract

Although Japanese cases of sporadic Creutzfeldt–Jakob disease (sCJD) generally involve longer survival periods compared to those from other countries, details regarding the factors influencing survival are unclear. To determine the influence of certain factors on survival, we retrospectively assessed 51 Japanese MM1-type sCJD patients with respect to background, clinical course, and disease management. No significant differences were found between men and women, tracheotomy and nontracheotomy patients, or patients treated in public and other types of hospitals. Although the survival period of tube-fed patients was significantly longer than that of patients who were not tube fed, survival of patients fed via a nasal tube did not differ significantly from that of gastrostomy-fed patients. The proportion of tube-fed patients was 68.6% (35/51). Disease duration was not significantly associated with age or year of onset. However, it was associated with time from onset to first recognition of myoclonus, first recognition of periodic sharp-wave complexes on electroencephalogram, and progression to the akinetic mutism state. Mechanical ventilation was not performed for any patient. Because the total disease duration increased in cases with a slowly progressive clinical course as a natural outcome, we concluded that the most crucial factor contributing to the prolonged survival of Japanese sCJD patients was tube feeding once the akinetic mutism state had been reached.