A Study On The Effect Of Sulfur Dioxide On The Risk Of Hypertension In The Jinchang Cohort

Objective:To investigate the effects of short-term and long-term exposure to sulfur dioxide（SO₂）on the number of outpatient and emergency departments（O＆ED）visits for hypertension and the risk of hypertension in a cohort,respectively,and to examine whether there is an association between occupational exposure to SO₂ and hypertension,so as to provide some evidence to clarify the association between SO₂ and hypertension.Method:Based on the Jinchang cohort platform,the data on the outpatient and emergency department（O＆ED）visits for hypertension from a workers’hospital between 2012 and 2016 in Jinchang City and the baseline and follow-up,including epidemiological survey and health examination information of the Jinchang cohort,were collected,as well as the environmental pollutant monitoring data(including SO₂,NO₂,PM₁₀)and meteorological observation data（including daily average temperature,relative humidity,wind speed）in the same study period were also collected.First,using a semi-parametric generalized additive model based on time series and controlling possible confounding factors to explore the relationship between short-term atmospheric SO₂ exposure and the number of O＆ED visits for hypertension.Then the stratified analysis by gender,age,and season were conducted.Secondly,the individual SO₂ exposure level during follow-up was estimated based on the home address of the cohort population,and the Cox risk proportional regression model was used to analyze the impact of long-term SO₂ exposure on the risk of hypertension after controlling for related confounding factors.A stratified analysis by gender,age,smoking,drinking,and occupation were conducted.Third,according to the new hypertension patients in Jinchang cohort,a random sample control group and a occupational matched control group were selected to conduct a 1:1 individual matched case-control study in a prospective cohort.Then a conditional Logistic regression model was used to explore the relationship between occupational SO₂ exposure and hypertension and possible dose response relationship.Results:（1）there was a significant association between short-term exposure to SO₂and the number of O＆ED visits for hypertension,and a lag effect was found.In the single lag model,the effect of SO₂ on the O＆ED visits for hypertension was statistically significant at lag 2 days（lag2）,lag 6 days（lag6）,and lag 7 days（lag7）,and when a10μg/m~3 increase in the daily average concentration of SO₂ at lag6 days,the number of O＆ED visits will increase by 0.916%（95%CI:0.642%～1.192%）.In the cumulative lag model,the effect of SO₂ on the O＆ED visits for hypertension was statistically significant at lag 06 days（lag06）and lag 07 days（lag07）,when a 10μg/m~3 increase in the daily average concentration of SO₂ at lag07 days,the number of O＆ED visits will increase 0.785%（95%CI:0.322%～1.249%）.The effect of SO₂ on the O＆ED visits in each subgroup were statistically significant.Among them,it has a greater impact on the O＆ED visits for hypertension among men and people over 65 years old.The SO₂ in the non-heating season has a significant effect on the O＆ED visits for hypertension.In the single-lag model,the ER at lag 6 days（lag6）,ER was 1.639%（95%CI:1.908%～2.183%）;In the cumulative lag model,the ER at lag 07 days（lag07）,was4.226%（95%CI:2.996%～5.471%）.（2）The results of a prospective cohort study show that long-term exposure to SO₂will increase the risk of hypertension.After adjusting for demographic characteristics,lifestyle and disease history,for every 10μg/m~3increase in SO₂ concentration during 2years exposure,the risk of hypertension in Jinchang cohort was 1.611（95%CI:1.419～1.830）.For every 10μg/m~3 increase in SO₂ concentration during 3 years exposure,the HR for the risk of hypertension was 2.128（95%CI:1.832～2.472）.The results of stratified analysis showed that long-term exposure to SO₂ in men,smokers,alcoholic drinkers,and workers affect the risk of hypertension more significantly than the control population.At the same time,high SO₂ exposure（above 60-70μg/m~3）has a more obvious risk of hypertension than low exposure（less than 40μg/m~3）.（3）A case-control study showed that occupational SO₂ exposure may be a risk factor for hypertension.In the case-control study with randomized control group,the OR for the SO₂ effect on hypertension was 1.932（95%CI:1.435～2.601）.In the case-control study with an occupational matched control group,the OR for the SO₂ effect on hypertension was 1.887（95%CI:1.349-2.640）.And there was a dose-response relationship,the exposure time and the risk of hypertension was found both in two match ways of case-control study,that is,the longer the occupational exposure period,the higher the risk of disease.Conclusion:（1）Short-term exposure to environmental SO₂ would increase the of O＆ED visits for hypertension,and there was a lag effect.The O＆ED visits for hypertension among men and elderly patients were more susceptible to the influence of SO₂.（2）Long-term exposure to SO₂ would increase the risk of hypertension.The results of the study suggest that as the exposure time increased,the risk of hypertension might increase.And men,drinking,and workers might have a higher risk of developing hypertension.High-concentration SO₂ exposure has a higher risk of hypertension than low-concentration SO₂ exposure.（3）Occupational exposure to SO₂ might be a risk factor for the onset of hypertension,and there was a dose-response relationship.（4）Controlling the concentration of SO₂ in the environment and strengthening the effective protection of the general population and occupational population were significant for reducing the risk of hypertension in the population.