Impact Of Temperature Changes Between Neighboring Days And Apparent Temperature On Epilepsy Outpatient Visits In Hefei

Objective（1）To explore the association between the relevant indicators of temperature change and the number of outpatient visits to epilepsy clinics in Hefei city;（2）To quantify the effect of air temperature change related indicators on the number of outpatient visits for epilepsy;（3）To find the sensitive population of epilepsy patients after short-term ambient temperature exposure to provide a scientific basis for health care and outpatient medical decision-making.MethodsInformation on patients attending each of the three outpatient clinics（Jixi road outpatient clinic,Yangtze River Road outpatient clinic,and high tech Zone outpatient clinic）of the First Affiliated Hospital of Anhui Medical University was collected through the outpatient electronic medical record medical system from January 1,2015 to December 31,2020,and included duration,age,sex,diagnosis,and residential address.Daily meteorological data,including maximum temperature,minimum temperature,mean temperature,relative humidity,wind speed,sunshine hours,24-h rainfall,atmospheric pressure,were collected at the same time periods from the China Meteorological Bureau.Temperature changes between neighboring days（TCN）were defined as the difference between the average daily temperature minus the average daily temperature on the previous day.The apparent temperature（AT）was calculated from a specific formula.Air pollutant data such as concentrations of particulate matter(PM_2.5,PM₁₀),nitrogen dioxide（NO₂）,sulfur dioxide（SO₂）,carbon monoxide（CO）,and ozone（O₃）were acquired from ten fixed monitoring stations in Hefei city.After adjusting for the main meteorological variables and air pollutants,a Poisson generalized linear model（PGLM）combined with a distributed lag non-linear model（DLNM）was used to evaluate the effects of temperature changes between neighboring days,apparent temperature,and mean air temperature on the person time of epilepsy visits in Hefei.No effect of high apparent temperature and high mean ambient temperature on epilepsy patient visits was observed.Subgroup analyses were performed by sex and age.ResultsBetween 2015 and 2020,a total of 28,020 epilepsy outpatient visits were included in Hefei,Anhui Province,with 16,301 visits（58.2%）for males and 11,719 visits（41.8%）for females.（28.4%）,45-59 years（23.2%）,and≥60 years（7.0%）.This study found correlations and lags between adjacent daytime temperature changes,apparent temperature,mean ambient temperature,and epilepsy visits.Using no change in adjacent daytime temperature（0°C）as a reference,the single-day lagged effect of a 3.9°C（5th percentile）decrease in TCN lasted approximately 7 days,showing an increasing and then decreasing trend,with the largest effect occurring on the 6th day of the lag（RR=1.042,95%CI:1.014-1.071）;the single-day lagged effect of a 3°C（95th percentile）increase in TCN lasted approximately 8 days,showing an increasing and then decreasing trend,with the largest effect occurring on the 6th day of the lag（RR=0.961,95%CI:0.936-0.987）.The lagged effect lasted approximately 8 days and showed an increasing and then decreasing trend,with the largest effect occurring at lag day 5（RR=0.961,95%CI:0.936-0.987）,which was not observed at post-exposure day 11.Using the median apparent temperature（16.9°C）as a reference,the single-day lagged effect of low apparent temperature（5th percentile,-1.5°C）lasted for approximately 6 days,with the largest effect occurring on lag day 1（RR=1.055,95%CI:1.015-1.097）and then decreasing over time,with no such effect observed on post-exposure day 7.Using the median,mean ambient temperature（17.4°C）as a reference,the single-day lag effect of low mean ambient temperature（5th percentile,2.1°C）was similar to the single-day lag effect of apparent temperature,lasting approximately 6 days,with the largest effect occurring on lag day 1（RR=1.058,95%CI:1.018-1.100）,decreasing over time after that,and disappearing on post-exposure day 7 post-exposure and disappeared.No effect of high apparent temperature and high mean ambient temperature on epilepsy patient visits was observed.Subgroup analysis found that males and patients aged 15-29 years were sensitive individuals to temperature change.ConclusionsThis study provides new strong evidence that adjacent declining daytime temperature,low apparent temperature,and low average ambient temperature are associated with an increased risk of seizure visits,and that increasing adjacent daytime temperature is associated with a decreased risk of seizure visits.It was also found that men and people aged 15-29 years were more vulnerable to temperature change.