Influence of air temperature on the number of hospital admissions due to chronic obstructive pulmonary disease at Shijiazhuang region

Based on the medical records of chronic obstructive pulmonary disease (COPD) from January 1 to December 31 of 2013 and the meteorological observation and air pollution data in the same periods,the influence of air temperature on the number of hospital admissions due to chronic obstructive pulmonary disease at Shijiazhuang region was analyzed using the generalized additive model to control the confounding effect of time trend and air pollution.The results show that three indexes,i.e.,the variable temperature in 24 h (BT),3 d lagged minimum temperature (T_min3) and 5 d lagged diurnal temperature range (Tc5)influence the number of the COPD hospital admissions at different extends.When BT is larger than -4.4 ℃ and equal or less than -0.7 ℃,T_min3 is larger than-3.6 ℃,equal or less than 3.2 ℃ and larger than 20.5 ℃,and Tc5 is larger than 0.9 ℃ and equal or less than 8.6 ℃,the relative risk (RR) of the COPD hospital admissions is 1.0207 (95%CI (Confidence Interval): 1.0074-1.0342),1.0118 (95%CI:1.0015-1.0222) and 1.0069 (95%CI:1.0005-1.0133),respectively with every 1.0 ℃ increase in these three temperature indexes.The results provide guidance for the COPD meteorological forecasting services.