arterial hypertension is the primary and most common risk factor for cardiovascular disease , stroke , end - stage renal disease , and peripheral vascular disease .
it has been identified as the leading cause of mortality and the third most common cause of disability - adjusted life - years worldwide .
it has been estimated that the worldwide prevalence of hypertension will increase from 26.4% in 2000 to 29.2% in 2025 .
identifying and characterizing modifiable risk factors of hypertension is of high importance for public health and clinical medicine .
the results of previous epidemiological studies have suggested that there is an association between greater risk of hypertension and lower physical activity , more marked adiposity , dyslipidemia , and a diet rich in saturated fatty acids .
correspondingly , lifestyle modification has been shown to lower arterial blood pressure ( bp ) and to reduce the risk of hypertension ; therefore , it maybe an essential component of early interventions in high - risk individuals . in 2010 , the american heart association defined seven factors ( smoking status , body mass index [ bmi ] , physical activity , healthy dietary score , total cholesterol , bp , and fasting blood glucose ) as metrics of cardiovascular health ( cvh ) .
subsequent studies have revealed that ideal cvh metrics have distinctly protective effects against stroke , cardiovascular disease , cancer , and overall mortality .
given that many of these studies involved the nonpopulation - based recruitment of participants , there was a risk of bias due to a referral - based selection artefact . additionally , the association between the risk of developing hypertension and cvh metrics was not explored .
moreover , as many of the studies were cross - sectional in nature , a change in the cvh metrics during follow - up and its influence on the incidence of hypertension could not be examined .
consequently , recent studies , such as the framingham heart study , have shown that assessment of the duration and grade of cvh metrics as a measure of cumulative exposure was more accurate than a cross - sectional analysis in examining the relationship between cvh metrics and diseases . in the framingham heart study ,
cumulative exposure to hyperlipidemia in young adulthood increased the subsequent risk of coronary heart disease .
the multi - ethnic study of atherosclerosis reported that cumulative exposure to elevated systolic bp ( sbp ) was correlated with an increase in the spot urine albumin - to - creatinine ratio among adults without diabetes .
as the relationship between the cvh metrics and the development of hypertension has not been explored , given that most previous studies were cross - sectional and not population - based and due to the fact that relevant information on the chinese population is scarce , we conducted this study to investigate the relationship between cumulative exposure to cvh metrics ( except for bp metrics ) and incident hypertension in a chinese population .
the kailuan study was a prospective cohort study conducted in the community of kailuan in the industrial city of tangshan ( china ) .
the study was approved by the ethics committees of kailuan general hospital and followed the guidelines outlined in the declaration of helsinki .
the kailuan study included employees and retirees of the kailuan group company , a large coal - mining company located in tangshan .
between june 2006 and october 2007 , a total of 101,510 individuals ( 81,110 men ) aged 18 to 98 years were recruited to participate in the study .
the present study included those individuals from the original study population who had not been diagnosed with hypertension at baseline examination and who underwent follow - up examinations in the years 2008 to 2009 , 2010 to 2011 , or 2012 to 2013 .
the study participants were re - examined every 2 years . at baseline and 2-year follow - up examinations , information about smoking , physical activity , and salt intake
never smoking was defined as the ideal health behavior ( with respect to smoking ) .
former smoking was identified as the intermediate health behavior , whereas current smoking was considered to be the poor health behavior . with respect to physical activity , ideal health behavior , intermediate health behavior , and poor health behavior
were defined as 80 , 1 to 79 , and 0  minutes of moderate or vigorous activity per week , respectively . since detailed information on diet ( eg , intake of fruits , vegetables , or meat ) was lacking , we used information on salt intake as a surrogate for information on diet in general .
as part of the standardized questionnaire , we asked how much salt participants used when they cooked .
 low  salt intake was defined as the ideal diet behavior , whereas medium and high salt intake were defined as the intermediate and poor diet behaviors , respectively .
bmi was calculated as body weight ( kg ) divided by the square of body height ( kg / m ) .
three readings of sbp and diastolic bp ( dbp ) were taken at 5-minute intervals after participants had rested in a chair for at least 5  minutes .
a 10-second 12-lead electrocardiography was used to measure their resting heart rate after they had rested in the supine position for 5  minutes .
high - density lipoprotein cholesterol ( hdl - c ) and low - density lipoprotein cholesterol ( ldl - c ) levels were determined using a direct test method ( interassay coefficient of variation < 10% ; mind bioengineering co. ltd . ,
( hs - crp)concentration was measured by high - sensitivity nephelometry assay ( cias latex crp - h , kanto chemical , tokyo , japan ) .
all biochemical variables were assessed at the central laboratory of kailuan general hospital using a hitachi autoanalyzer ( hitachi 747 ; hitachi , tokyo , japan ) . according to the definitions presented by the american heart association ,
bmi was classified as ideal ( < 25  kg / m ) , intermediate ( 2529.9  kg / m ) , or poor ( 30  kg / m ) .
bp was categorized as ideal ( sbp < 120  mm hg and dbp < 80  mm hg and untreated ) , intermediate ( 120  mm hg    sbp    139  mm hg , 80  mm hg    dbp    89  mm hg , or treated to sbp / dbp < 120/80  mm hg ) , or poor ( sbp 140  mm hg , dbp 90  mm hg , or treated to sbp / dbp > 120/80  mm hg ) .
fasting blood glucose was classified as ideal ( < 5.6  mmol / l and untreated ) , intermediate ( 5.66.9  mmol / l or treated to < 5.6 
total cholesterol status was rated as ideal ( < 200  mg / dl and untreated ) , intermediate ( 200239  mg / dl or treated to < 200  mg / dl ) , or poor ( 240  mg / dl or treated to 200  mg / dl ) . to examine cumulative exposure of 6 cvh metrics ( except the bp metric ) , we created a dichotomized variable for each component of the health metrics :  ideal  was coded as 2 ,  intermediate  was coded as 1 , and 
the total ideal cvh score of each individual was the sum score of the 6 ideal cvh metrics , ranging from 0 to 12 .
the cumulative cvh ( cumcvh ) score was defined as the summed cvh score for each examination ( baseline or follow - up ) multiplied by the time between the 2 consecutive visits in years : cvh1    time12    cvh2    time23    cvh3    time34 , where cvh1 , cvh2 , and cvh3 indicate cvh at examinations # 1 ( baseline ) , # 2 , and # 3 , respectively , and time12 , time23 , and time34 indicate the participant - specific time interval between the consecutive examinations # 1 to # 3 in years .
cumcvh was categorized as < 44 points , 44 to 48 points , 49 to 54 points , 55 to 59 points , and 60 points .
information on demographic and clinical characteristics ( age , sex , alcohol consumption , personal monthly income , level of education , and history of diseases ) was collected via questionnaires . according to their age at baseline
, study participants were classified into 3 categories : < 40 years , 40 to 59 years , and 60 years .
previous history of diseases , including myocardial infarction , stroke , and cancer , was assessed as self - reported . the use of antihypertensive , cholesterol - lowering , and glucose - lowering medications within the past 2 weeks before the baseline interview was also investigated .
 incident hypertension was diagnosed in study participants with an sbp of less than 140  mm hg ; a dbp less than 90  mm hg ; no history of hypertension and no use of antihypertensive drugs at examinations # 1 through # 3 who had an sbp of at least 140  mm hg ; a dbp of at least 90  mm hg ; and/or use of antihypertensive drugs at examination # 4 performed from 2012 to 2013 .
statistical analyses were performed using commercially available software ( sas 9.3 ; sas institute ; cary , nc ) .
continuous variables were described as the mean    standard deviation ( sd ) and were compared by analysis of variance ( anova ) or the kruskal 
categorical variables were described as percentages and were compared using the chi - square test .
a logistic regression model was used to estimate the risk of hypertension associated with cumcvh metrics .
model 3 further adjusted for hs - crp , ua concentration , resting heart rate , parental history of hypertension at baseline , and medication usage before the fourth follow - up examination . because 11 hospitals were responsible for laboratory tests in this study , we used a random - effects model for each hospital to account for potential measurement bias .
the interactions between cumcvh and both sex and age on the risk of hypertension were analyzed using multivariate logistic regression .
all statistical tests were 2-sided , and the significance level was set at p  <  0.05 .
of the 101,510 individuals who participated in the baseline examination , 86,496 were excluded due to a diagnosis of hypertension before the examination in the period from 2012 to 2013 ( 61,144 participants , with 44,653 having a diagnosis of hypertension before the period from 2006 to 2007 , 11,607 developing hypertension between 2007 and 2009 , and 4884 developing hypertension between 2009 and 2011 ) ; a missed follow - up examination during the re - examination period of 2008 to 2009 , 2010 to 2011 , or 2012 to 2013 ( 22,699 participants ) ; or incomplete cvh metrics data ( 2653 participants ) .
the remaining 15,014 participants ( 33.5% women ) were included in the present study ( fig .
1 ) . selection of kailuan study participants . compared with the excluded subjects , the individuals included in the present study were significantly younger ( 43.7    11.1 vs 50.5    13.4 years ; p  <  0.001 ) , had a higher level of education ( 30.9% vs 24.0% ; p  <  0.001 ) , and had a lower bmi , sbp , dbp , fasting blood glucose , total cholesterol , hs - crp concentration , ua concentration , and resting heart rate ( table 1 ) .
comparison of demographic and other characteristics of participants and nonparticipants . after comparing the baseline characteristics ( data obtained in 2006 ) across the 5 groups of study participants
, it was revealed that the higher cumcvh score was significantly ( p  <  0.001 ) associated with older age , the female sex , a higher level of education , a higher income , lower alcohol consumption , a lower resting heart rate , lower ua concentration , and lower hs - crp concentration ( table 2 ) .
characteristics of study participants after stratification by cumulative cardiovascular health factor index . in a multivariate regression analysis , with cumcvh score as the dependent variable and the aforementioned variables that were significantly associated with cumcvh score in the univariate analysis as the independent variables , it was found that cumcvh score was significantly correlated with older age ( p  <  0.001 ) , the female sex ( p  <  0.001 ) , level of education ( p  <  0.001 ) , and level of hs - crp concentration ( p  <  0.001 ) the incidence of new - onset hypertension ranged from 16.76% in the lowest cumcvh category to 11.52% in the highest cumcvh category ( table 3 ) .
compared with participants in the lowest cumcvh category ( < 44 points ) , after adjusting for age , sex , education level , income level , hs - crp concentration , ua concentration , resting heart rate , parental history of hypertension at baseline , and medication usage before the third follow - up examination , participants in the highest cumcvh category ( 60 points ) had a significantly reduced risk of hypertension ( adjusted or 0.60 , 95% ci 0.500.71 ) .
for every increase in cumcvh score category , the risk of hypertension decreased by approximately 2% ( or 0.98 , 95% ci 0.970.98 ) .
significant inverse associations were found in 2 age groups ( p  <  0.001 ) , both for men ( p - trend < 0.001 ) and for women ( p - trend
there were significant interactions between cumcvh score and both age ( p - interaction < 0.001 ) and sex ( p - interaction  =  0.013 ) .
associations between incident arterial hypertension and other factors ( multivariate analysis ; odds ratios , and 95% confidence intervals ) in the study participants after stratification by cumulative cardiovascular health factor index . to examine the influence of individual cvh metrics on the association between cumcvh score and incident hypertension , a sensitivity analysis was performed after excluding each of the 6 metrics from the total cumcvh score 1 at a time .
odds ratios and 95% confident intervals associated with hypertension risk in relation to a 1-score increase in cumulative exposure to cardiovascular health ( cvh ) factors , after removing each one of the 6 cvh metrics separately . for the models adjusted for age , sex , education level , income level , alcohol consumption , high - sensitivity c - reactive protein concentration , uric acid concentration , resting heart rate , parental history of hypertension at baseline examination , and medication usage before the third follow - up examination .
because follow - up time might influence cumcvh score ( eg , participants might have a higher cumcvh score at 4-year follow - up than those at 3-year follow - up ) , we used a time - weighted cumcvh ( calculated as [ cvh1    time12  +  cvh2    time23  +  cvh3    time34]/[time12  +  time23  +  time34 ] ) model to examine the robustness of our findings .
the results revealed that higher time - weighted cumcvh score was significantly associated with a lower risk of incident hypertension ( table 4 ) .
associations between incident arterial hypertension and other factors ( multivariate analysis , odds ratios , and 95% confidence intervals ) in the study participants after stratification by time - weighted cumulative cardiovascular health factor index .
in this prospective kailuan study , a higher cumcvh score significantly reduced the risk of incident hypertension .
this association remained significant when the total study population was stratified by sex and age , and after adjusting for potentially confounding factors , such as education level , income level , alcohol consumption , parental history of hypertension at baseline , and medication usage before the third follow - up examination .
these findings suggest that optimal cvh status is helpful to reduce the risk of incident hypertension .
the framingham heart study investigators were among the first to develop a hypertension risk prediction model that included age , sex , sbp , dbp , bmi , cigarette smoking , and parental history of hypertension .
results of a meta - analysis of 13 prospective cohort studies showed an inverse dose - response association between level of recreational physical activity and risk of hypertension .
the strong heart study found that increasing abdominal obesity and an abnormal lipid profile were major predictors of arterial hypertension development in adults who initially had optimal bp .
in addition , dietary fat was an important modifiable risk factor of hypertension in previous studies .
a limitation of the studies mentioned above was that the behavioral factors were measured at a single time point without taking into account their change in cvh metrics over time .
they neglected any behavioral factors and indexes , including cvh metric changes due to environmental change and aging .
given the variability in the behavioral factors , we investigated the association between cumulative exposure to behavioral factors ( ideal cvh metrics ) and hypertension prospectively .
the results remained unchanged when the population was stratified by sex and age , both of which were associated with other risk factors , such as smoking . in addition , the relationship between cumcvh exposure and incident hypertension decreased in statistical strength , but persisted when 1 of the 6 cvh metrics was removed from the total cumcvh score .
it suggested that each of the cvh metrics was influential in reducing the risk of incident hypertension .
furthermore , each of these individual risk factors appeared to be associated with similar hypertension risk , as the correlation between cumcvh exposure and incident hypertension was attenuated to a comparable extent after their individual removal from the model ( fig .
these findings also imply that preventative efforts to reduce the development of arterial hypertension that encompass strategies promoting a more holistic approach to optimal vascular health ( eg , smoking cessation , weight loss , increased physical activity , and low - fat diet ) may yield greater benefits than would be expected by targeting individual health behaviors independently .
the association between higher cumcvh score and lower incidence of hypertension in the follow - up examinations aligns with and may be caused by the known relationships among a low degree of physical activity , a high bmi , smoking , and increased bp .
since we did not include factors , such as socioeconomic background , in the statistical analysis in our study , we could not assess their influence on the relationship between cvh and the incidence of arterial hypertension .
based on previous studies on social inequalities and health and mortality , however , there may be little doubt that individuals with lower socioeconomic status , including a lower level of education , have a lower cvh score , and , therefore , a higher risk of having arterial hypertension at follow - up .
future studies may address the question regarding whether socioeconomic factors had a direct influence on the development of hypertension or whether there was an indirect influence of lifestyle factors , such as diet and amount of physical activity .
first , we used self - reported information on salt intake as a surrogate of diet information without measuring the natriuresis for 24  hours . for a subgroup of the study population , however , we compared the self - reported assessment of salt intake with the measurement of 24-hour natriuresis and found a significant correlation ( r  =  0.78 ) .
this finding may indicate that the self - reported data on salt intake provided some information about salt intake .
second , all participants came from the city of tangshan and were employees or family members or employees of the kailuan group company ; consequently , the study population was not representative of the total chinese population . therefore , the findings of our study can not be generalized to other chinese populations with a different lifestyle and a different average education level .
the strengths of our study included the sample size and the prospective examination of the participants .
third , we included in the study only individuals who were free of arterial hypertension at 3 baseline examinations over a period of 6 years .
that is , individuals who were free of arterial hypertension at the first baseline examination , but developed arterial hypertension by the second or third baseline examination were excluded from the study . as an alternative to the selected study design , we could have included these individuals as incident hypertensive patients in the study .
nevertheless , given that bp measurement performed at a single examination or at two examinations could yield a false - negative diagnosis of arterial hypertension , we chose the design involving 3 negative measurements as baseline for our longitudinal investigation .
this research decision may only have strengthened the quality of our study design because it prevented the inclusion of patients , who were inaccurately determined to be normotensive , but who actually had arterial hypertension , into our study population . in conclusion , a healthy lifestyle as indicated by cumcvh score was related to a reduced risk of having arterial hypertension .
 abstractideal cardiovascular health ( cvh ) has been defined by the american heart association as the absence of disease and presence of 7 key health factors . 
 since it is unknown whether cumulative exposure to cvh reduces the risk of developing arterial hypertension , we prospectively examined the potential association between cumulative cvh ( cumcvh ) score ( except for blood pressure metrics ) and incident hypertension.of the 101,510 participants with an age range of 18 to 98 years in this longitudinal community - based kailuan study , our cohort included those 15,014 participants without hypertension at baseline and who had follow - up examinations 2 , 4 , and 6 years later . 
 cumcvh was calculated as the summed cvh score for each examination multiplied by the time between the 2 examinations ( points    year ) . 
 based on the cumcvh score , the study population was stratified into groups of < 44 points , 44 to 48 points , 49 to 54 points , 55 to 59 points , and 60 points.incidence of hypertension ranged from 16.76% in the lowest cumcvh category to 11.52% in the highest cumcvh category . after adjusting for age , sex , education level , income level , high - sensitivity c - reactive protein concentration , uric acid concentration , resting heart rate , parental history of hypertension at baseline , and medication usage before the third follow - up examination 
 , participants in the highest cumcvh category had a significantly reduced risk of incident hypertension compared with those in the lowest cumcvh category ( adjusted odds ratio 0.60 , 95% confidence interval 0.500.71 ) . 
 for every increase in category based on the cumcvh score , the risk of hypertension decreased by approximately 2% ( odds ratio 0.98 , 95% confidence interval 0.970.98 ) . 
 the effect was consistent across sex and age groups.a higher cumcvh score is associated with a lower risk of incident hypertension . 
Introduction
Methods
Results
Discussion