[Time series analysis on the effect of ambient fine particulate matters and temperature interactions on schizophrenia admission in Tongling City of Anhui Province, 2014-2017].

Objective: To explore the effect of ambient fine particulate matters (PM(2.5)) and temperature interaction on schizophrenia admission. Methods: All admission data were retrieved from the Psychiatric Hospital and Municipal Hospital of TongLing from January 1, 2014 to December 31, 2017. Daily air pollution and meteorological data were collected from the Tongling Environmental Protection Agency and Meteorological Bureau, respectively. A distributed lag non-linear model combined with the generalized additive model were applied to explore the effects of PM(2.5), multi-pollutants, and the interaction between temperature and PM(2.5) on schizophrenia admission. The stratification of temperature was divided by three criteria. The low temperature layer was defined as P(95) or >P(90) or >P(80) was defined as the high temperature layer. Results: From 2014 to 2017, 6 642 patients were admitted for schizophrenia in Tongling, and the median of PM(2.5) and temperature were 47.0 µg/m(3) and 17.5 ℃, respectively. The median concentration of PM(2.5) (P(50)) was taken as a reference. When the exposure concentration of PM(2.5) was P(90), the lagged effect appeared in the first day with RR=1.03 (95%CI: 1.00-1.07) and reached the maximum in the fifth day with RR=1.16 (95%CI: 1.13-1.19). In the multi-pollutant models, it was found that the simultaneous inclusion of PM(2.5) and NO(2) had higher risk of schizophrenia admission, with the RR=1.18 (95%CI: 1.15-1.22), P<0.001. The risk of schizophrenia admission caused by PM(2.5) exposure at high temperature was greatest under the three temperature stratification standards, which were 12.1% (8.5%-15.7%), 9.7% (6.9%-12.6%) and 17.1% (11.6%-22.8%), all P values <0.001. Conclusion: With the increase of PM(2.5) concentration, the risk of schizophrenia admission is increased, and the risk effect of PM(2.5) is stronger at high temperature.