INVESTIGATION OF HEATSTROKE IN THE JONAN DISTRICT OF TOKYO

Abstract

The purpose of this investigation was to clarify the characteristics of heatstroke in the Jonan district of Tokyo. We retrospectively evaluated the age, gender, comorbidity, situation at the time of onset, and prognosis of 16 severe heatstroke patients at Showa University Hospital and compared these characteristics with Heatstroke STUDY2010. The period of this study was from June 2009 to September 2011. The M: F gender ratio was 9: 7, and the mean of age was 73.8 years. The situation at the onset was normal daily life in almost all cases. The details of these cases are normal indoor life (73%), walking (20%), rest room (7%). The comorbidites were sequela of the central nervous system (100%), rhabdomyolysis using continuous hemodiafiltration (6%), disseminated intravascular coagulation[DIC] (44%), and liver damage(38%). Regarding the prognosis, the mortality rate was 6% (only one case). Although the summer of 2010 was the hottest in Japanese surveillance history, the difference between the years from 2009 to 2011 was not apparent as far as we looked over the difference between cases at Showa University Hospital. The reason why the proportion of DIC was apparently high at Showa University Hospital is speculated to be that the mean of age at Showa University Hospital is higher than Heatstroke STUDY2010. On the other hand, the mortality rate at Showa University Hospital is lower than Heatstroke STUDY2010. We believe this is because all cases at Showa University Hospital were admitted to the intensive care unit and treated with critical care. In conclusion, the most effective strategy for heatstroke in the Jonan district is to prevent classical heatstroke of elderly people. The provision of services for elderly people is, therefore, necessary to improve heatstroke morbidity in the Jonan district.