The Effects Of Smoking Behavior And SGK Family Genes On The Onset Of Hypertension

Background and objectiveTobacco smoking is a risk factor for various chronic diseases,including cancer,cardiovascular disease,and stroke.In 2010,the prevalence of tobacco smoking was 28.1%in Chinese adult population,and 72.4%adult non-smokers were exposed to second-hand smoke(SHS).Furthermore,one million deaths were attributed to tobacco smoking in 2010 and China is suffering from the heavy burden of health toll and economic loss attributed to smoking.In 2003,World Health Organization launched the "Framework Convention on Tobacco Control",which offered a series of comprehensive tobacco control measures and gave the priority to monitoring tobacco epidemic.Acting as the demonstration city of tobacco control in china,Beijing has endeavored to tobacco control since 1995.After the Beijing 2008 Olympic Games,additional tobacco control measures were put into effect,including raising tobacco product tax,enlarging the space for health warning language on package,and no smoking in more public places.Additionally,Beijing launched the strictest tobacco control law named"Beijing tobacco smoking control ordinance",which forbids smoking in all indoor public places and workplaces.Therefore,we conducted the current survey to investigate the prevalence of active and passive tobacco smoking among Beijing residents in 2011,to evaluate previous tobacco control measures,and to provide basic information for future evaluation of the strictest law.Subjects and MethodsA stratified multistage cluster random sampling method was employed to select a representative sample of 20 242 participants aged 18-79 among Beijing residents.A standardized and validated questionnaire was administered by trained research staff to collect information about tobacco smoking.Ever smokers included persons who have consumed at least 100 cigarettes or 100 grams of tobacco during their lifetime.Current smokers were ever smokers who have smoked in 30 days prior to the survey.Passive smokers were non-smokers and former smokers who have been exposed to SHS for at least 15 minutes per day and at least one day per week.A comprehensive weight was calculated based on the 2010 Beijing Population Census data and the sampling scheme.The complex survey design and comprehensive weight were taken into account to the estimation of prevalence,number,and mean.ResultsThe mean age of 20 242 participants was 44.37 years,including 9 179 males and 11 063 females.The prevalence of ever smokers and current smokers was 33.13%and 30.18%,with an estimate of 4 994 815 current smokers aged 18-79 years in 2011.55.53%males were current smokers,and over 96%and 40%of current smokers smoked every day and over 20 cigarettes daily,respectively.By contrast,the prevalence of current smokers in females was 3.21%.The mean of cigarette smoked daily and age of smoking initiation was 14.35 cigarettes and 17.92 years for male,and 9.83 cigarettes and 24.97 years for female,respectively.41.73%of male and 45.41%of female current smokers intended to quit smoking.The prevalence of passive smokers was 44.74%among overall population,with an estimated number of 5 171 047 in 2011.Males were exposed to SHS mainly in workplace(32.46%)and restaurant(10.12%),while females were mainly at home(28.92%)and in workplace(17.76%).Among passive smokers,57.62%were exposed to SHS over five days per week and 36.48%were exposed every day.ConclusionTobacco smoking prevalence is still extremely high in Beijing.Nonsmokers do still suffer from SHS critically.Further urgent efforts for tobacco control are warranted in Beijing.Background and objectiveHigh blood pressure is a main public health challenge worldwide due to its high prevalence and subsequent cardiovascular disease.Previous studies showed the prevalence of hypertension has increased dramatically recent decades in China.In 2014,290 million hypertension cases were identified in Chinese adult population with a prevalence of 27.8%.Furthermore,tow million Chinese died due to hypertension in 2010,and urgent efforts are warranted for the control of hypertension.China is the biggest producer and consumer of tobacco,and 60 thousands and one million Chinese died due to tabacco smoking in 2005 and 2010,respectively.Tobacco smoking is a well-established risk factor of cardiovascular disease.However,the results on the association of tobacco smoking with hypertension from previous studies are still equivocal.Therefore,we conducted the current prospective cohort study to elucidate the association of tobacco smoking with incident hypertension in general Chinese adults.Subjects and MethodsParticipants for the current study were from four cohorts,the China Multicenter Collaborative Study of Cardiovascular Epidemiology(ChinaMUCA)1992-1994,the ChinaMUCA 1998,the International Collaborative Study of Cardiovascular Disease in Asia,and the Community Intervention of Metabolic Syndrome in China&Chinese Family Health Study.Finally,60 142 participants aged 16 to 88,who were free of hypertension at baseline,were included.A standardized questionnaire was used to collect information on tobacco smoking.During baseline examination and follow-up duration,three consecutive blood pressures(BP)were measured by well-trained staffs using validated sphygmomanometer following standard procedure,and the mean of the three readings was treated as the BP value.Incident hypertension was defined as a mean SBP ? 140mmHg,and/or DBP ? 90mmHg,and/or use of antihypertensive medication in the previous 2 weeks at follow-up examination among participants who were normotensive at baseline examination.COX proportional hazard regression model was used to examine the association between tobacco smoking and incident hypertension and to calculate Hazard Ratio(HR)and 95%Confidence Interval(95%CI).ResultsOverall,the mean age of 60 142 participants was 48.4 years.Among them,23 484 were males with a mean age of 49.1 years and 36 658 were females with a mean age of 47.9 years.The proportion of nonsmokers,former smokers,and current smokers was 35.3%,7.8%and 56.9%among males,respectively.And those were 97.5%,0.3%and 2.3%among females,respectively.After a follow-up of 7.7 years on average and 463660.8 person-years totally,14 629 incident hypertensions(6 242 males and 8 387 females,respectively)were identified.Compared with never smokers,the multivariate-adjusted HR and 95%CI for former and current smokers were 1.11(1.01,1.22)and 1.09(1.03,1.15)for males and 0.53(0.37,0.77)and 0.92(0.80,1.04)for females,respectively.A linear dose-response association was observed between number of cigarette smoked daily and pack-years smoked lifetime and incident hypertension in males(Ptrend=0.025 and Ptrend?0.020,respectively),while no evidence was found in females.Subgroup and sensitivity analyses revealed similar results.ConclusionTobacco smoking is the risk factor for incident hypertension with a dose-response manner in Chinese adult males,but not for females due to the limited sample size.More urgent tobacco control measures are highly demanded to reduce tobacco consumption and promote smoking cessation,and then to cure the epidemic of hypertension.Background and objectiveChina's aging population,increased urbanization,and Westernization have contributed to the emergence of hypertension and related cardiovascular diseases as major public health challenge.As a complex trait,blood pressure(BP)is influenced by environmental and genetic factors and their interactions.Previous heritability studies have shown that roughly 31%-68%of interindividual variation in BP is determined by genetic background.The serum and glucocorticoid regulated kinases(SGK)family genes play a pivotal role in determining sodium balance,blood volume,and BP level through its regulation of Na+ transport in kidney.However,few studies have tested the association between SGK family genes and BP and documented inconsistent findings.In current study,both single-marker and gene-based analyses were employed to examine the associations of common variants in SGK family genes with longitudinal BP changes and incident hypertension in Han Chinese.Subjects and MethodsOur study recruited 1 768 participants from the Genetic Epidemiology Network of Salt Sensitivity(GenSalt)study and GenSalt follow-up study.A standardized questionnaire was employed by trained staffs to collect information of family structure,sociodemographic characteristics,medical history,and lifestyle factors from participants.The same BP measuring procedure was employed in baseline and two follow-up visits.Three consecutive BP readings were obtained on each day of 3-day examination.The mean of nine BP readings was calculated at each of three visits.The additive associations of 101 tag-SNPs,from SGK family genes,with longitudinal BP phenotypes were tested by Mixed-model.Also,gene-based analyses were conducted by the truncated product method(TPM)and the Gene-based Association Test that uses Extended Simes procedure(GATES).Bonferroni correction was used to adjust multiple testing.ResultsThe mean age of 1 768 participants was 38.97 years,with 924 males.After an average 7.23-year follow-up,the mean systolic BP(SBP)and diastolic BP(DBP)increased by 12.17 mmHg and 8.42 mmHg,respectively.And 512(32.10%)participants free of hypertension at baseline developed hypertension.Three novel SNPs in the SGK1 gene were predictive of the longitudinal BP phenotypes.The major allele of SGK1 rs1763498 conferred 2.86-fold increased risks of hypertension development(P=1.0×10-4).In addition,the major allele of SGK1 rs229133 was significantly associated with 0.43 mmHg larger annual increases in SBP(P=4.2×10-4),while the major allele of SGK1 rs6924468 was significantly associated with 0.23 mmHg smaller annual increases in DBP(P=4.2×10-4).Gene-based analyses revealed an association of the SGK1 gene with risk of hypertension development(P=7.4×10-3 for TPM;P?7.0×10-3 for GATES).No evidence for the SGK2 and SGK3 genes was found.ConclusionIn conclusion,novel SNPs in the SGK1 gene were associated with SBP longitudinal changes(rs229133),DBP longitudinal changes(rs6924468),and incident hypertension(rsl763498)in single-marker analyses,respectively.Also,gene-based findings also supported an association between SGK1 gene and incident hypertension.The findings contribute important information towards better understanding the genomic mechanisms and biological pathways underlying BP regulation.Future studies are still needed to replicate our findings.Furthermore,functional studies will be important for identifying the causal variants driving the observed SGK1 gene signals.