A Study On Epidemiology Of DaYao Sudden Unexplained Death

[Obejective] To seek some possible clues of the causes and give an elementary etiological hypothesis, based on describing the epidemiological distribution and clinical characteristics of Yunnan DaYao sudden unexplained death (YSUD) in detail.[Methods] A surveillance system was developed to collect the information of new and old YSUD cases, in order to analyze the distribution of time, regional and population and clinical characteristics. The study of Cardiac enzyme was conducted to compare the difference between the case village and the control village. The study of pedigree was conducted for the further genetic analysis. [Results](1) Distribution and clinical characteristicsThere were 49 cases in 8 villages of DayaoYunnan province from 1995 to 2007.①Regional distribution: YSUD often happened in some villages in north-center of the province, and most of clustering cases occurred in altitude of 2100～2300m.②Time distribution: Increasing tendency appeared in recent years, and most of cases emerged in July and August.③Population distribution: Young minority people, especially female,were susceptible population.④Clinical characteristics: Typical characters were rapid-onset and sudden death, 39 percent cases died in one hour. The prodrome occurred in few patients, but in acute period some patients felt dizzy, chest tightness, flustered, malaise, and so on.(2) The study of Cardiac enzymeThe Cardiac enzyme was abnormal in the case village and some control villages during the epidemic time and the non-epidemic time, which implied that there were risk factors to the hearts.(3)The study of pedigreeThe 29 YSUDs of the Ajizhu villiage distributed in 6 families. Out of the 6 families the no. 5 families had the most YUSD patients, that is to say, there were 12 YUSDs of the 43 family members. Besides, there were consanguineous marriage in the villiage. There were not enough evidence for existing etiological hypotheses, such as heart diseases and biologic toxic mushroom poisoning. However, according to the disease pattern, we provide a reasonable hypothese for further study.[Conclusions]①The household and village clustering of YSUD did exist.②There was severe heart damage in the YSUD region.③The pedigree of the Ajizhuo villiage was not the typical way.