ABSTRACT
Objective To observe the mortality and its changes on liver cancer in the past 30 years as well as to describe the spatial distribution of liver cancer deaths between 2005 and 2010 in Lingbi,Anhui province.Methods Using the mortality data from 1973-1975 and from 2005 to 2010 in Lingbi to compare with the relative national and historical data,to observe the trend of rapid increase on liver cancer mortality in Lingbi.Using the Poisson model,BYM model and hotspot detection method,standardized mortality ratio (SMR),relative risk(RR) value of liver cancer deaths of each village were calculated and the clustering of high liver cancer deaths was identified.Results Through an increase of 223.7％ on the SMR of liver cancer in the past 30 years,the standardized mortality of liver cancer in Lingbi had an increase of 74.1 percent than the national level in 2005-2010 but it was 22.7％ lower than the country level in 1973-1975.The SMR and RR values and their P values were higher in the villages which were located along the Kuisui River.Data from the clustering analysis showed that there had been significantly positive autocorrelation at the altitude of 5300 meters,and a very obvious hot spot of liver cancer deaths existing along the Kuisui River,especially at the bifurcation of the old Sui River and new Sui River was observed.Conclusion There was an alarming increase of liver cancer mortality in the past 30 years in Lingbi.The high mortality area mainly covered the villages along the Kuisui River,suggesting that there were common risk factors for hepatocellular carcinoma in the population at risk.
ABSTRACT
<p><b>OBJECTIVE</b>To explore the association between mortality rate of hepatic carcinoma and the distance from Suihe River in Lingbi county, Suzhou, Anhui province.</p><p><b>METHODS</b>Using the disease mapping and spatial statistical analysis techniques,we described the spatial distributions of the mortality rate of hepatic carcinoma from 2005 to 2010 in Lingbi county. Taking the distance between villages and polluted rivers as proxy variable of environmental exposure, mortality rate of hepatic carcinoma in each village as dependant variable, and using the Glimmix model and Bayesian spatial model (BYM) to undertake the univariate and multivariate analysis, we investigatived the association between mortality rate of hepatic carcinoma and the water pollution of Suihe River in Lingbi county.</p><p><b>RESULTS</b>Obvious clustering of high mortality rate of hepatic carcinoma along the polluted river was observed in Lingbi county. Results of Glimmix model showed that whether spatial autocorrelation was considered or not, closer to the polluted river has higher mortality rate of hepatic carcinoma. Results of univariate analysis of the BYM model showed that, compared with the villages far from the polluted river more than 12 km (the mortality rate of hepatic carcinoma was 33.12/100 000(1068/3 224 562) ), the RR values of the hepatic carcinoma mortality was 1.38(95%CI:1.06-1.82) for the villages apart from the polluted river within 6 km (the mortality rate of hepatic carcinoma was 42.48/100 000(777/1 829 064)), and 1.13 (95%CI:0.92-1.39) for villages apart from the river between 6 and 12 km (the mortality rate of hepatic carcinoma was 35.65/100 000(651/1 825 848)). In the BYM model multivariate analysis, adding the volume of fertilizer and pesticides used per cultivated area, GDP per capita to do multivariate analysis were, the relation between mortality rate of hepatic carcinoma and distance from polluted rivers remains unchanged.</p><p><b>CONCLUSION</b>The mortality rate of hepatic carcinoma was associated with the exposure to the polluted river in Lingbi county. The polluted river may increase the hepatic carcinoma mortality of nearby residents.</p>