南充市自发性脑出血发病与气温的相关性及滞后效应

Correlation and lag effects between spontaneous intracerebral hemorrhage and ambient temperature in Nanchong city

目的分析南充市自发性脑出血(sICH)发病与气温的相关性及滞后关系。方法收集南充市全市范围内二级以上医院2014年1月至2018年12月收治的sICH患者病例资料及同期气温数据,利用Spearman等级相关法确定最佳温度指标,将其组建分布滞后非线性模型,评估其与sICH日发病风险的暴露-剂量反应关系,分层分析各温度节点在性别及年龄组别的滞后-剂量反应关系。结果共收集sICH患者资料13952例。Spearman相关性分析揭示sICH日发病人数与日均气温呈非线性负相关(r=-0.324,P<0.05)。分布滞后非线性模型分析结果表明极低温和低温当天sICH的相对危险度为1.68(1.35~2.08)及1.47(1.24~1.72),危害效应最大,其随着滞后天数增加而减弱,极低温滞后1~2 d,低温持续滞后1~10 d。低龄组(18~60岁)在极低温、低温下滞后2 d,高龄组(>60岁)在极低温下滞后10 d,低温下滞后24 d。不同性别组在极低温、低温下滞后效应趋势一致,随滞后天数增加风险下降。结论低温增加sICH发病风险,早期呈明显急性影响,且具有滞后效应,老年人对低温反应更加滞后。

Objective To analyze the correlation and lag relationship between spontaneous intracerebral hemorrhage(sICH)and temperature in Nanchong City.Methods The data of clinical information at grade-C secondary or above hospitals and air temperature were collected retrospectively from January 2014 to December 2018 in Nanchong city.Spearman rank correlation method was used to determine the optimal temperature index,and a distribution lag non-linear model was established to evaluate the exposure response relationship between the temperature and the daily risk of sICH,and analyze the lag response relationship of temperature nodes in gender and age groups.Results A total of 13952 patients with sICH were collected.Spearman correlation analysis revealed that the daily incidence of sICH was negatively correlated with daily average temperature(r=-0.324,P<0.05).The results of the distributed lag nonlinear model analysis showed that the relative risks of sICH on the day of extremely low temperature and low temperature was 1.68(1.35-2.08)and 1.47(1.24-1.72),and the hazard effect was the largest,which weakened with the increase of lag days.The extremely low temperature lags for 1-2 d,and low temperature lags 1-10 d.The harmful effects in the younger group(18-60 years old)at extremely low temperature and low temperature lag for 2 d,while the harmful effects in the elderly group(>60 years old)at extremely low temperature and low temperature lag to 10 d and 24 d,respectively.The lag effect trend of different gender groups in extremely low temperature and low temperature was consistent,and the risk decreased with the increase of lag days.Conclusion Low temperature increases the risk of sICH.It has obvious acute effect in the early stage and has lag effect.The elderly people’s response to hypothermia is more delayed.