Acute Effects of Metrological Factors on Cerebrovascular Diseases among Type2 Diabetes Patients: case crossover evidence from Beijing, China

Background: Acute effects of metrological factors on cerebrovascular diseases (CBVD) have become a growing public health concern. However, the impact of those factors on CBVD among type 2 diabetes (T2D) patients has not been well studied in the study area. The main aim of this study was to assess the acute effects of metrological factors including temperature, relative humidity and atmospheric pressure on incidence of CBVD among type 2 diabetes patients in Beijing, China. Methods: Data was obtained from 258 large general hospitals from the Beijing Public Health Information Center Cardiovascular Case Database and China. Meteorological Administration covering 16 districts in Beijing from 2014 to 2018. Time-stratified case crossover design with a distributed lag nonlinear model (DLNM) was used by considering 27 lag days on CBVD admissions. Results: Within five years (January 2014–December 2018), a total of 223,216 cases for cerebrovascular disease were collected after excluding nonlocal admissions, of which 9,541 (4.27%), 149,757 (67.09%), 7,444 (3.33%), 31,356 (14.05%), and 23,912 (10.71%) were hospitalized for hemorrhagic stroke, ischemic stroke, atherosclerosis, intracranial aneurysm, and apoplexy sequela, respectively. In short, male participants and elderly individuals (≥65 years) accounted for 57.6% and 61.7%, respectively. Generally, the cumulative exposure-response curve for temperature was almost inverted “V”-shaped, with a slight increase at concentrations of higher than 25°C. The cumulative exposure response curve for relative humidity was almost linear. The cumulative exposure-response curves for atmospheric pressure were V-shaped, which meant that both high and low concentrations of atmospheric pressure may increase the risk of cerebrovascular disease incidence among patients with T2D. Conclusions: The results of this study indicate that both an increase and a decrease in temperature and atmospheric pressure had a significant association with the occurrence of cerebrovascular disease among co morbid patients with diabetes. This study provides evidence of the short term effects of metrological factors on hospital admissions of CBVD among T2D patients. Keywords: Keywords: Admission; Beijing; Cerebrovascular disease; Distributed lag nonlinear model; Metrological factors, Type 2 diabetes