The Impact Of Ambient Temperature And Air Pollutants On The Years Of Life Lost Among Residents In Lanzhou City

Objective 1.To describe the trend of air pollutants concentration in Lanzhou City from 2014 to 2017;2.To analyze the association between the years of life lost?YLL?and the daily average temperature or air pollutant concentration for non-accidental causes,respiratory diseases and cardiovascular diseases.Methods The YLL was used as the health burden indicator,and the distribution lag nonlinear model?DLNM?was used to comprehensively assess the impact of temperature and air pollution on the population.1.The daily meteorology data?2014-2017?were obtained from Lanzhou meteorological monitoring station,while the daily air pollutant data were collected from the Lanzhou Environmental Monitoring Center.The simultaneous,daily death data were collected from the Centers for disease control and prevention of Lanzhou,which covered the four districts of the main city from 2014 to 2017?Chengguan District,Qilihe District,Anning District,Xigu District?.2.DLNM was applied to explore the association of YLL and the temperature and atmospheric pollutant concentration for non-accidental total death,respiratory diseases,cardiovascular diseases.Results1.As seasonal trends of all the air pollutants were observed in 2014-2017,which showed higher level in winter but lower level in summer,while O₃ had an opposite trend;2.The daily deaths of non-accidental causes,respiratory diseases and cardiovascular diseases in Lanzhou City from 2014 to 2017 were higher in the spring and winter,particularly in January and December;3.Significant associations were found among all meteorological factors and air pollutants?P<0.05?,except between daily average temperature and relative humidity,as well as between daily average relative temperature and CO?P>0.05?;4.Nonlinear relationship was found between daily average temperature and the YLL.Higher temperature was found to affect the YLL in the lag 3 days,and it has a large effect at lag 4-7 days,but the effect gradually disappears after 7 days.Lower temperature induced a harmful effect on the YLL after lag 7,which increased with the number of lag days and could last to 30 days;5.The YLL of non-accidental total death attributed to high temperature was slightly higher than that from respiratory disease and cardiovascular disease.Rising from 19.7°C to 28.4°C,the YLL from non-accidental death reached the maximum in lag 0⁴ days for each IQR increase of the daily average temperature?YLL:60.18,95%CI:0.11,120.25?,which was significantly higher for male death?highest YLL at lag 7,YYL:61.90,95%CI:13.78,110.02?than that of the female.The death of 65+group reached the maximum at lag 0⁷ days?YYL:69.96,95%CI:40.65,99.28?,and was significantly greater than the group younger than 65 years old.The cold temperature effect,dropping from 2.5°C to-6.1°C,induced great YLL from non-accidental death and reached the maximum at lag 0³0 days for each decline of 1IQR?YLL:191.58,95%CI:71.46,311.70?,which was substantially greater in women and 65+population;6.Significant effects of PM_2.5,SO₂,CO and O₃ were found on the deaths from respiratory diseases.?1?Along with the increase of PM₁₀0 and NO₂,the change of YLL was not statistically significant.?2?In addition,after 15 days of accumulation,each10?g/m³ increase of PM_2.5.5 increased 2.00 years of YLL among the 65+population with respiratory diseases?95%CI:0.38,3.62?.?3?SO₂ had an impact on YLL from non-accidental and respiratory diseases deaths,which SO₂ mainly had impacts on the male and the group younger than 65 years with respiratory diseases.The YLL of non-accidental deaths?24.36 years,95%CI:1.02,47.70?and respiratory diseases by?11.19 years,95%CI:3.12,19.27?reached the highest after 15 days'accumulation.The YLL of 0-65 years old population?YLL:7.41 years,95%CI:0.37,14.45?reached maximum at lag 15 days.?4?CO had an impact on YLL from respiratory diseases deaths,which CO mainly had impacts on the male and 65+population with respiratory diseases.For each 1 mg/m³ increase of CO,the YLL from respiratory disease increased by 11.00 years?95%CI:0.23,21.77?at lag 7,and reached the maximum at lag 15?13.28 years,95%CI:0.80,25.77?.At lag 15,YLL from male death showed the highest at lag 15?YLL:13.28 years,95%CI:0.80,25.77?.In different age groups,the YLL from 65+year death reached 7.57 years?95%CI:0.14,14.99?at the lag 15.?5?O₃ had an impact on YLL from 65+population with respiratory diseases deaths,which had an impact on YLL from non-accidental and cardiovascular diseases deaths.At lag 7,there was significant increase of YLL from cardiovascular disease death of for every 10?g/m³ increase in O₃,which increased by3.27 years?95%CI:0.77,5.77?,there was significant increase in population from the group of 65+years with non-accidental deaths and respiratory disease populations.The YLL from non-accidental deaths increased by 2.47 years?95%CI:0.30,4.64?at lag 7,while the YLL from respiratory disease increased by 1.26 years?95%CI:0.18,2.35?at lag 15.Conclusions1.Low temperature may have more obvious impacts on YLL of non-accidental deaths compared with higher temperature;2.The SO₂ have more obvious impacts on YLL of non-accidental deaths and CO may lead to more serious death burden for people with respiratory diseases;3.Men are more susceptible to high temperature,SO₂ and CO,while women are more susceptible to low temperature;4.The 65+people are more susceptible to high temperature,PM_2.5,CO and O₃,while the group younger than 65 years may be more susceptible to SO₂.