Ambient Daily Average Temperature And Daily Citizen Mortality In Shenyang,1992-2000

Objective1. To describe the relationship between short - time daily average temperature and daily mortalities caused by all death, respiratory and cardiovascular disease, injury and tumor from 1992 to 2000 among residents in Shenyang city and analyze effect of the change of daily temperature on mortality.2. To estimate the lag time of daily temperature on mortality.3. To determine the vulnerable age groups of daily temperature change.MethodFit mortalities caused by all death, respiratory and cardiovascular disease, injury and tumor were estimated using generalized additive model ( GAM) controlling for long time trend, humidity and air pressure smoothed by local regression (Loess) , day of week and season then inducing daily average temperature and its lag times into the model. Based on the chart between adjusted mortality and daily temperature, the relationship between disease specific mortality and daily average temperature was quantitatively analyzed by log - line model and so as the relationship between daily average temperature and daily mortalities of five age groups caused by all death, respiratory, cardiovascular diseases.Result1. Similar with other studies, a significant graphically "V" shape relationship between mortality caused by all death, respiratory, cardiovascular diseases and ambient temperature was found. The relationship between tumor, injury disease mortality and temperature is not significant.2. The estimation of inflexion of daily average temperature effect on mortality is between 22 ~25 C for all death, cardiovascular and respiratory death. Thetemperature change of 1 C apart from the inflexion could increase 0.7 ~ 2. 2% mortality. The result is similar with the estimation of 0. 4 ~ 3. 0% mortality change from other studies.3. The mortality caused by all death, cardiovascular, respiratory disease decreases with the increasing of temperature as a whole, especially for respiratory diseases. Increasing trend of injury mortality with the temperature increasing was found but without significance.4. A inverse "S" shape relationship between mortality caused by all death, respiratory, cardiovascular disease and ambient temperature was found among elder groups, which is different from that in total people.5. No significant effect of age on relationship between temperature and mortality was found.6. For deferent age groups, the lag time of daily average temperature effect is increased along with age increasing. And the lag time of temperature effect is longer for respiratory disease death than that for cardiovascular death among all age groups except for age group of less than 15. But the trend is not significant for total people.ConclusionThe relationship between short - time daily average temperature and daily mortalities was found based on the dataset analyzed. But the effect is not monotone increasing or decreasing. A "V" shape relationship between temperature changes and mortality was observed for all death, respiratory and cardiovascular disease. The relationship between tumor, injury disease mortality and temperature is not significant. The range of daily average temperature corresponding the lowest mortality of population studied is between 20 ~ 24 C and the range of it corresponding the highest mortality is between - 8 ~ - 15 C for the elders. No significant effect of age on relationship between temperature and mortality was found. The lag time of temperature effect is longer for respiratory disease death than that for cardiovascular death among all age groups.