Studies On The Associations Of Metal Exposure With The Risk And Prognosis Of Hypertension

Part?Environmental exposure to metals and the risk of hypertensionObjective:The study was conducted to assess the associations of environmental exposure to metals with the odds of hypertension as well as blood pressure?BP?levels using urine samples in a Chinese general population.Methods:The present exploratotory study of 823 eligible participants was conducted with a cross-sectional design.Urine sample was used as biomarkers to reflect the levels of environmental exposure to 20 metals.Multivariable regression models were applied to assess the potential association.Multi-metal models were utilized to investigate the impacts of co-exposure to various metals.Results:Based on the results from various models,positive trends for increased odds of hypertension with increasing quartiles of vanadium,iron,zinc and selenium were suggested.Compared with those in the lowest quartiles,participants in the highest quartiles of vanadium,iron,zinc and selenium had a 4.4-fold,4.9-fold,4.2-fold and2.5-fold increased odds of having hypertension,respectively.High urinary mercury level was found to increase the levels of diastolic blood pressure?DBP?.Individuals in the highest group of Hg were found to have a 4.3 mmHg higher level of DBP.Conclusions:Our findings suggest that environmental exposure to vanadium,iron,zinc,selenium and mercury may increase the risk of hypertension or elevate the levels of BP.Part?Studies on the associations of metal exposure,genetic polymorphisms and their interactions with the risk of hypertensionObjective:The study was conducted to investigate the associations between genetic polymorphisms and the risk of hypertension,and the modification effects between genetic polymorphisms and metal exposure on the risk of hypertension.Methods:The present study of 497 cases and 497 controls was conducted with a case-control design.The associations between genetic polymorphism of 36 SNPs in 9genes and the risk of hypertension were studied using logistic models.The interactions between genetic polymorphisms and the exposure to cadmium and mercury were inverstigated on both the additive scale and the multiplicative scale.Results:Among the 36 SNPs in 9 genes,significant associations of rs1008140 in eNOS and the haplotype in CAT with the risk of hypertension were found.Multiplicative interactions between rs2566508 and rs2566511 in eNOS and cadmium exposure for hypertension were observed,while additive associations between rs1008140 and rs3918196 in eNOS and cadmium exposure for hypertension were suggested.Multiplicative interactions between mercury exposure and the 5 SNPs,rs2566508 and rs2566511 in eNOS,rs10488736 and rs17881846 in CAT,and rs1610216in MT2A,were significant for the risk of hypertension.The interaction between mercury exposure and rs10488736 in CAT remained significant after adjustment for multiple testing(P_FDR=0.048).Conclusions:Associations between cadmium and mercury exposure and the risk of hypertension may be modified by genetic variants in eNOS,CAT and MT2A.Part?Associations of co-exposure to heavy metals with renal function in a hypertensive populationObjectives:The study was conducted to explore the associations of metal exposure with renal function in participants with essential hypertension.Methods:The present study of 934 participants with essential hypertension was conducted with a cross-sectional design.We measured the levels of chromium,cadmium,thallium and uranium in urine and calculated the estimated glomerular filtration rate?eGFR?for renal function.Multivariable linear regression models adjusted for potential confounders were applied.Results:After adjusting for potential confounders and other metals,doubling of urinary chromium or uranium levels decreased eGFR by 2.90 mL/min per 1.73 m²?P<0.001?and 1.87 mL/min per 1.73 m²?P=0.004?,respectively.Co-exposure to chromium and uranium was found to decrease eGFR greatly,particularly in women.Compared with those in the low exposure group,women with high exposure to chromium and uranium had a 11.36 mL/min per 1.73 m²?P<0.010?adjusted decline in eGFR.Higher urinary thallium levels were positively related to elevated eGFR in men.The adjusted increase in eGFR with doubling of thallium levels was 3.12 mL/min per1.73 m²?P=0.002?.Conclusions:Environmental exposure to chromium and uranium may contribute to a decline in eGFR in individuals with hypertension.The associations of exposure to heavy metals with eGFR may be sex-different.