[Study of appropriate surveillance of health appraisal for communities]

A study to determine the appropriate surveillance of health appraisal for communities was made using individual data for deaths in 1992-1996 in Maniwa County (population 51,000), individual data of medical examinations from 1995 to 1997 in Maniwa and other county (population 24,000), rate for people receiving medical examinations from 1983 to 1996 in Maniwa County and life table data for Japanese males in 1995. The results obtained were as follows: (1) The total YPLL (Years of Potential Life Lost) rate was reversely correlated with the proportion of people who had a medical examination as compared to the total population, with a time lag of about 6 years (P < 0.05). It can be concluded that past health appraisal may influence future indicators of death with a time lag of about 6 years. (2) In the case of calculation of Years of Potential Life Lost rate (YPLL rate = sum of ¿target age - (death age + 0.5) between n1 and n2 ages¿/population), if the target age is close to the n2, the number of deaths close to the n2 have a possibility of very small evaluation to influence of number of these near to n1. Therefore a target age must be set up some years above n2. (3) There is a peak point (about 90 years) among 0 and 99 years old for the YPLL rate in life tables for Japanese males in 1995 using the target age of 100. On the other hand, using a target age of 120 there was a linear increasing from about 75 age with no peak. Then, if YPLL rate with a target age of 100 is used, there may be big different values among n2 before peak age and after peak age. (4) To perform appropriate surveillance of health appraisal for communities (population size: 1000-2000), two indicators must be used. One is a simple rate for number of death peoples of some diseases to total population or of peoples who have an abnormal indicator on some medical examinations to total number of peoples who have a medical examination, in which case that person's age is not be considered. The other is Age-Adjusted YPLL or YPHL (Years of Potential Health Lost) rate not using a data of standard population that have been showed next equation. A target age should be set at 120, as a maximum age of human life rather than 80 or 100. Age - Adjusted T(n1 - n2) YPLL rate(by Inoue) [formula: see text] T: A target age (value of 120 is appropriate), n1: youngest individual age, n2: oldest age, i; individual age between n1 and n2, pi: population (in the case of YPHL rate, it shows a number of peoples receiving medical examination) at age of i, Qi: number of death on some disease (number of peoples who have an abnormal indicator on some item of medical examination) at age of i.