Associations Between PM2.5 Exposure Duration And Physical Activity Intensity On The Health Of Hypertension In Urban Residents Of Beijing

Regular physical activity can lower the blood pressure of patients with hypertension,but people increase their physical exercise while also increasing their exposure to air pollution,thereby increasing the health risks to the human body.The study evaluated the combined effects of PM2.5 exposure duration and physical activity intensity on systolic blood pressure(SBP)and diastolic blood pressure(DBP)of hypertension.Total 2613 patients(≥18-year-olds)at baseline who attended surveys from China Health and Nutrition Survey(2011–2015)in Beijing were selected,as well as the PM2.5 data collected in the same period.The Mixed Linear Effects Model and mixed analysis of variance(MANOVA)were used to explore the multiple effects of PM2.5 exposure duration and PA intensity on SBP and DBP,respectively.The correlation results indicated PM2.5 exposure duration(>15day)occurred more significant correlations with DBP,and longer PM2.5 exposures duration(>60day)with SBP.The linear mixed effects model showed the important random terms of gender,PA levels and BMI classification for both SBP and DBP.It also indicated the significant fixed effect from age for both SBP and DBP,and the significant fixed effects from PM2.5 and weight,as well as the interactive in DBP.The random effects of PA levels put effects on different weight people for SBP and on different age people for DBP,while the person of SBP exposed to PM2.5 environments may tend to be affected by BMI classification.The random effect of BMI classification may influence the SBP through the weight first.The model main effects showed PA and the interaction with gender could put significant effects on BP,especially no gender difference in middle PA level for SBP and in low PA level for DBP.The gender effects and the PA level effects were also improved by the MANOVA results.We concluded that the more PM2.5 exposure duration may lead to more significant correlation with higher BP values.The age is the main factor for the BP health.The variables of gender,PA levels and BMI classification could induce the different effects on the health.PA can improve BP health through the imposed actions on age and weight,etc.For SBP of people who exposed to PM2.5 environments,it may tend to be affected by BMI classification,and which also may influence the DBP through the weight adjusting first,and then caused hypertension.The gender difference of BP may be affected by PA showing the higher PA level and the more gender difference.