Lagged effect of ambient temperature on hospitalization for cardiovascular diseases in Wuwei, suburbs Northwest China

Studies on the effect of ambient temperature on the number of hospitalizations for cardiovascular diseases in rural Northwest China are rare, and there is a gap in related studies in Wuwei, a less developed city located in Northwest China. We collected hospitalization data from patients with cardiovascular diseases from the new Rural Cooperative Medical Insurance Scheme in Wuwei and meteorological data from the Gansu Provincial Meteorological Bureau and investigated the effect of ambient temperature on the number of hospitalizations for cardiovascular diseases in rural Wuwei, by means of distributed lag nonlinear models (DLNMs). A total of 53,642 patients with cardiovascular diseases were included from 1 January 2011, to 31 December 2015. The damaging effect of low temperature gradually increased with increasing lag time, and the damaging effect of high temperature reached its maximum on the same day (lag0); the heat effect caused more damage than the cold effect; and for both low and high temperatures, the relative risk (RR) was greater among female and elderly patients than among male and adult patients. This study may provide a theoretical basis for relevant departments to formulate meteorological policies to protect the health of susceptible people.