Abstract: AIM: To evaluate the effect of the causes of death of advanced schistosomiasis
patients on the life span of population in an area where schistosomiasis had been under control
by applying the indicators of potential years of life lost (PYLL) and rate of PYLL(PYLLR).
METHODS: Using the formula of calculation of PYLL and PYLLR,the causes of death of 487 patients
of advanced schistosomiasis in 3 previously endemic townships of Shanghai suburb . RESULTS: Of
487 cases who died between 1955 and 1995, the PYLLR of all causes of death was 256.3‰. The main causes of death were hepatic fail re ( 100.3‰) , liver carcinoma (43.4‰) and cancer of other organs (24.8‰). In the 1960s, the PYLLR of advanced schistosomiasis comlicated with hepatic failure and upper digestive tract hemorrhage was 222.2‰ and 34.5‰, the PYLLR of the complications of schistosomal liver cirrhosis, hepatic failure and hemorrhage accounted for 67.5% of the total PYLLR, being apparently higher in the non-splenectomy group than in the splenctomty group . After the schistosomiasis was under control, both PYLL and PYLLR decreased linearly. As compared with the 1960s, the PYLLR of all causes of death and the causes of death of the complications of schistosomal liver cirrhosis in the 1990s has declined by 62.9% and 83.2% , respectively, the PYLLR of upper digestive tract hemorrhage was found only 0.3‰ in the last 5 years. CONCLUSION: PYLL and PYLLR analysis could be used to quantify the effect of complications of advanced schistosomiasis and other causes of death on the life span of population.

Key words: Potential years of life lost（PYLL）, rate of PYLL, advanced schistosomiasis