Spatial clustering analysis of Budd-Chiari syndrome in Heze City of Shandong Province / 中国地方病学杂志

ABSTRACT

Objective To investigate the spatial distribution and clustering areas of Budd-Chiari syndrome in Heze City,Shandong Province,and to provide epidemiological information for further exploring the etiology and related risk factors of the disease.Methods Detailed residential addresses of 342 cases of patients (residents of Heze City) with diaphragm type Budd-Chiari syndrome diagnosed between 1995 and 2004 in Heze Municipal Hospital,Heze Shan County Central Hospital,Affiliated Hospital of Xuzhou Medical College,Shandong Provincial Hospital and Beijing Xuanwu Hospital were collected.Geographic information system (GIS) was used as a platform for data management and display.The nearest neighbor index,Ripley's K(d) function,Ripley's L(d) function and the nearest neighbor clustering method were applied to detect the spatial characters of Budd-Chiari syndrome in Heze City,Shandong Province.Crimestat 3.0 was used for spatial analysis.Results The nearest neighbor distance analysis showed that the nearest neighbor index was 0.6767 (Z =-11.4387,P ＜ 0.01).That was an aggregation at the first-order spatial scale.Within the study area,the first clustering radius of Budd-Chiari syndrome was 6.66 km,and the first clustering strength was 5.40; the average radius of the strongest clustering area was 126.61 km,and the clustering strength was 12.52,while the biggest clustering radius was larger than 222 km.After corrected by population,the gathering strength was slightly higher than that before the correction.Ten first-order hot spots were formed,and 95％ confidence interval aggregation number was 7,which meant the results were statistically significant(P ＜ 0.05),main clustering areas are in Mudan District,Shan County and Juancheng.One secondorder hot spot was gathered based on the first-order hot spot.Conclusions Spatial distribution of Budd-Chiari syndrome in Heze City,Shandong Province has showed spatial aggregation and heterogeneity.This study has a great epidemiological significance for further exploring the cause of Budd-Chiari syndrome.