Effects of diurnal temperature range on Intracerebral hemorrhage among middle-aged and elderly people in Central China

Abstract Objective This study aimed to evaluate the effect of diurnal temperature range (DTR) on the number of admissions for intracerebral hemorrhage (ICH) in middle-aged and elderly population. Methods We collected DTR and the diurnal hospital admission data of patients with ICH over 45 years old, as well as mixed factors such as meteorology and air pollutants in Hunan Province during 2019 as a representative area of central China and analyzed with a distributed lag nonlinear model. Results In total, there were 54 690 ICH admissions in Hunan Province with 30.76% in middle-aged and 69.24% in the elderly. After controlling for other confounding factors, this study found that there was a non-linear relationship between DTR and the number of ICH hospital admissions in middle-aged and elderly groups. In spring, low DTR(middle-aged < 3℃, elderly < 4℃) with continuous low temperature will increase the risk of ICH admissions in both middle-aged and elderly groups ,while high DTR only increase the middle-aged admission risk; Low DTR with continuous high temperature will increase the risk of ICH admissions only in the middle-aged during summer; Autumnal high DTR also caused high risk in both groups; Low DTR(< 3℃) with continuous low temperature or high DTR will increase the risk only in elderly groups in winter. In the elderly groups, the effect of DTR occurs within 5 days, but occurs after 11 days in the middle-aged group. Conclusion High DTR may increase the risk of ICH admissions in middle-aged and elderly groups in central China, and elderly group is more sensitive to the impact of DTR. The risk effect of DTR on ICH was significantly different in different seasons between different groups. It is recommended that DTR values should be reported and highlighted in weather forecasting services, with specific interventions targeting sensitive populations.