Impacts Of Temperature On Cardiovascular Diseases In Beijing Under Climate Change

Addressing climate change is one of the greatest global challenges in the 21st century.Climate change has increased the surface temperature and the frequency and intensity of extreme weather events,which will pose potential threats to the survival and health of residents.Beijing is facing multiple challenges such as coping with climate change,urbanization,and aging population,but few studies that systematically consider the health effects of climate change,urbanization,and aging population.Therefore,it is necessary to research the impact of temperature in Beijing on the health of cardiovascular diseases under the climate change.Firstly,this study used the data on meteorological factors,air pollutants,and daily cardiovascular mortality in Beijing from 2006 to 2011.With the generalized additive model and the distributed lag nonlinear model,the exposure response relationship between temperature and cardiovascular mortality in different populations were established.Subsequencely,this study discussed the health effects of temperature on different population groups with different gender,age,and educational attainment in urban and suburban areas,and explored the modification effect of the urbanization level(different heights of buildings in urban areas)on the temperature-health effects.In addition,the attributable risks of cardiovascular mortality in different populations caused by temperature were analyzed,then estimated the influence of urban heat island(UHI)effect on the attributable risks of cardiovascular mortality in urban areas.Using the geographic information system(GIS),the exposure level of the population in different seasons was evaluated,and the population-weighted temperature was calculated.Finally,five scenarios were designed to predict the future additional deaths from temperature-related cardiovascular diseases,and explored the independent and comprehensive effects of climate change,population changes,urbanization level and aging population on the prediction of future death from temperature-related cardiovascular diseases.The main conclusions as follows:(1)The impacts of daily average temperature on cardiovascular mortality in Beijing differed in space and population.The overall cumulative exposure response curve between daily average temperature and cardiovascular mortality in the urban and suburban areas of Beijing showed a"U"shaped at lag 0-14,and the minimum mortality temperature(MMT)in the urban area(23?)was higher than that in the suburbs(21?).The excess risk(ER)for cardiovascular mortality of daily average temperature changed by 1?was higher in suburban areas than in urban areas,and the ER of heat effects(>MMT)of different people was higher than the ER of cold effects(<MMT)in urban and suburban areas.In suburban areas,the adverse effects of temperature(both heat and cold)were more significant for females than those for males.However,in urban areas,the effects were inconsistent for both genders.For the populations living in either urban or suburban areas,people aged?65 years and illiterate subjects suffered from greater risks of both heat and cold effects than their counterparts.(2)The attributable risks of daily average temperature in Beijing for cardiovascular mortality were related to the cold-heat effects and population characteristics,and the death burden of cold effects were dominated.The attributable risks of daily average temperature in Beijing for cardiovascular mortality of different populations showed that the attribute fractions(AFs)caused by temperature for cardiovascular mortality were higher in males than in females,and the AFs in people aged?65 years were significantly higher than in people aged<65years,and the AFs of populations with primary education and above were slightly higher than that of the illiterate population.The attributable risks of daily average temperature for cardiovascular mortality showed that the AFs for the cold effects were16.75%(95%CI:11.27,21.54),which was higher than the heat effects by 2.97%(95%CI:2.20,3.68).The AFs caused by moderate cold(2.5^th of temperature?MMT)were 15.57%(95%CI:10.36,20.22).(3)Beijing's urbanization had varying degrees of modification on the impacts of daily average temperature-cardiovascular mortality relationship.The city center in Beijing had the highest temperature,and most of the city's population lived in areas with higher temperatures.The daily average temperature changed by 1?,the ER of heat and cold effects decreased with the height of buildings rise.Residents living with a high level of urbanization had a lower health risks of temperature-related cardiovascular mortality.Due to the urban heat island effect,the AFs of heat effects for urban resident's cardiovascular mortality increased by 0.48%,while the AFs of cold effects decreased by 0.57%.The decrease of cold effects AFs offset the increase of heat effects AFs.The urban heat island effect had a protective effect on the attributable risks for cardiovascular mortality in urban areas caused by temperature.(4)Under different climate change,factors such as urbanization level and aging population would have a certain impact on future additional deaths from temperature-related cardiovascular mortality.Considering climate change only,future additional deaths from temperature-related cardiovascular diseases would increase with the temperature rise.Considering climate change and population change,future additional deaths from temperature-related cardiovascular diseases were consistent with the corresponding population change under the corresponding climate change scenarios.Compared with the same level of urbanization,increasing the level of urbanization could make the mortality risks from temperature-related cardiovascular diseases decrease by 1.0%?12.5%in the future.Compared with the same level of aging,intensified aging population could make the mortality risks from temperature-related cardiovascular diseases increase by21.6%?277.9%in the future.On the basis of considering climate and population change,only considering intensified aging population could make the mortality risks from temperature-related cardiovascular diseases increase by 48.8%?325.9%in the future,and considering the integrated effects of increasing the level of urbanization and intensified aging population could make the mortality risks from temperature-related cardiovascular diseases increase by 44.1%?256.6%in the future,which were slightly lower than the increase that only considered the intensified aging population.In conclusion,the intensified aging population was the biggest disadvantage in tackling climate change,which would obviously magnify the mortality risks of temperature-related cardiovascular diseases in the future.Although the advancement of urbanization would alleviate the adverse effects of the intensified aging population,the mitigation effects would be limited.Therefore,multi-sectoral joint work and research mechanisms such as meteorology and medical health need to be established in Beijing,and policies related to mitigate climate change and reduce baseline mortality rate(especially the elderly)should be formulated.In addition,relevant departments should improve the medical health care level and optimize the allocation of social resources.Only in this way will climate change be better tackled and the health of residents be better protected.