最低气温对兰州市呼吸系统疾病就诊人次的影响研究

Effects of minimum temperature on respiratory diseasesin Lanzhou

通过2013年1月1日~2017年7月31日兰州市呼吸系统疾病逐日就诊资料和气象资料,采用分布滞后非线性模型(DLNM)方法,分析0~30d滞后影响,研究极端低温对不同年龄(<15岁、16~45岁、46~60岁、>60岁)和性别人群呼吸系统疾病就诊人次的影响.结果发现:日均最低温度对相对危险度(RR)的最大RR变化范围为0.89~1.41,变化趋势整体呈现出V字型,在低温附近,温度越低,RR越高;滞后0~4d,极端低温代表的冷效应影响最为显著;滞后5~19d,在日均最低温度0°C附近,出现新的峰值,冷效应对RR的贡献有所下降,热效应对RR的贡献完全消失;滞后20~30d,日均最低温度为-10°C时,出现RR最小值,0°C温度点附近维持RR峰值;滞后22d时,滞后影响完全消失.在极端低温条件下,呼吸系统疾病对低龄人群表现出长期滞后性和高发性,对高龄人群表现出短期滞后性.男性比女性患病的滞后效应更长,患病风险更大.

In the current study,we evaluated the effect of extreme low temperature on respiratory diseases in Lanzhou from January 1,2013 to July 31,2017 using a distributed lag non-linear model(DLNM)based on the daily data of meteorology and hospital visitsfor respiratory diseases.Age(≤15years,16-45years,46-60years,≥60years)and gender(male and female)modification were also performed.Results indicatedthe greatestlag effect of average daily minimum temperature(Tmin)on relative risks(RRs)for respiratory diseases.The maximum RR value ranged from 0.89 to 1.41 and the response-effect curvewas V-shaped.At lag of 0~4d,the cold effect represented by extreme low temperature was the most significant.Atlag of 5~19d,a new peak appeared near Tmin at 0°C,and the cold effect started to decrease,while the heat effect disappeared completely.At lag of 20~30d,the minimum RR value appeared when Tmin was-10°C and the peak value was near the temperature point of 0°C.Lag effect completely disappearedat 22d.Under extreme low temperatures,respiratory diseases showed long-term hysteresis and higherrisksforthe younger ages,while short-term hysteresis and lowerriskforthe older ages.As to the gender,males showed a longer lag effect than females.