Potential Impact And Applicability Of The 2017AHA/ACC Hypertension Guidelines On The Chinese Population

BackgroundIn November 2017,the American heart association/American college of cardiology(AHA/ACC)released new hypertension guidelines,which changed the diagnostic criteria from the previous systolic blood pressure(SBP)/diastolic plood pressure(DBP)of 140/90 mm Hg down to 130/80 mm Hg.Objective1.To qualitatively analyze the cognition and dimensions of Chinese medical workers on the potential impact of the 2017AHA/ACC guidelines.To clarify the magnitude of its local influences,so as to provide clues for subsequent quantitative analyses.2.To quantitatively analyze prevalence of hypertension in people aged 40 years and older in China under the 2017 AHA/ACC guidelines and identify key regions in China for hypertension prevention and control;To explore the individual and regional variables contributing to the geographic differences in the prevalence of hypertension and new diagnoses under the 2018 Chinese hypertension guidelines(hereafter referred to as the Chinese hypertension guidelines)and the 2017 AHA/ACC guidelines,as well as applicable regions for the 2017 AHA/ACC guidelines.3.To quantitatively explore the relationship of cardiovascular disease(CVD)risk with SBP,DBP and blood pressure level under the 2017 AHA/ACC guidelines in different age groups,and on this basis evaluate the applicability of the 2017 AHA/ACC guidelines for the prevention of CVD amongst the middle-aged and the elderly populations.Methods1.Classic Grounded Theory: 31 people who worked in fields related to hypertension prevention,control,diagnosis,and treatment were selected by the purposive sampling for interviews.Subsequently,the contents of the interviews were open coded and selected coded based on the classic grounded theory,so as to understand the impact dimensions of 2017AHA/ACC guidelines and to evaluate its applicability.2.Big data analysis: data from the 2015 “National Screening and Intervention of the Population Susceptible to Stroke” database was used.The national project collected blood pressure and related information on 271764 subjects over across 31 provinces,municipalities,and autonomous regions in China through a two-stage cluster sampling method,after individuals with missing critical variables were excluded,a total of 237142 subjects were included in the study.Hypertension prevalence was estimated by stratified weighting with a complex sampling design.Alternatively,the geographic distribution of hypertension in province level was visually displayed through the Arc Map,the extent to which individual(demographic factors and lifestyle factors)and regional variables contributed to spatial differences in the prevalence of hypertension under different criteria was measure and explain by a multilevel logistic regression model.The median odds ratio(MOR)was used in the dual-level null model to assess spatial differences in prevalence of hypertension and new diagnoses at the provincial level under different criteria and MOR >1 indicates that there are geographical differences,and then the null model was subsequently supplemented with individual variables and regional variables to assess the explanatory power of various independent variables on the geographic variation through the proportion of change in variance(PCV)at the provincial level,the larger the PCV,the greater the influence of the variables on the geographical differences in hypertension.3.Cross-sectional study: Data was collected from the annual project of “Screening and Intervention of the Population Susceptible to Stroke” in Hubei Province in 2019,which collected blood pressure and related information on 17562 subjects aged 40 years and over from 9 communities in 5 cities within the province using a randomized cluster sampling method,after individuals with missing critical variables were excluded,a total of 16567 individuals were eventually included in this part of the analysis.The continuous changes of the CVD risk with the SBP and the DBP levels among the middle-aged(40-59 years)and the elderly(≥60 years)populations were first evaluated separately using a restricted cubic spline(RCS)model.During the analysis,SBP = 130 mm Hg and DBP = 80 mm Hg were adopted as the reference points to assess their preventive values for CVD among the two age groups,and the preventive effect of these two cut-off points for CVD events was assess.Subsequently,the preventive effect of stage 1 hypertension(SBP 130-139 mm Hg/DBP 80-89 mm Hg)in the 2017 AHA/ACC guidelines on the CVD was evaluated using a rare events logistic regression model,thereby clarifying the applicability of the American guidelines in the middle-aged and the elderly populations in China.Results1.Cognition and dimensions of Chinese medical workers on the potential impact of the down-regulation of the diagnosis criteria for hypertension: “impact on the population”and “applicability to the population” are main aspects that China should consider for the down-regulation of the diagnosis criteria.The study found that three perspectives of “impact on the population”,namely “healthcare burden”,“early recognition and prevention”,and“population psychological impact”,the frequency of occurrence in the interview is 114,29,and 22 respectively.In addition,“applicability to the population” should incorporate three aspects,including “current status of hypertension”,“authoritativeness of guideline recommendations”,and “specificity of the Chinese population”,the frequency of occurrence in the interview is 114,29,and 22 respectively.2.Status of hypertension under different criteria and the new diagnoses: A total of113090 and 182412 screened subjects were diagnosed with hypertension according to the local and the 2017 AHA/ACC guidelines respectively,69322 of which were new diagnoses.The weighted prevalence was 37.08%(95%CI: 35.45%-38.71%)and 58.52%(95%CI:56.90%-60.14%)respectively for the middle-aged and the elderly populations,and the weighted prevalence of new diagnoses was 21.44%(95%CI: 20.17%-22.71%).3.Geographical distribution of hypertension and the explanatory power of individual and regional variables on its geographic variation: No matter which diagnosis criteria was adopted,regions with high prevalence of hypertension among the middle-aged and the elderly populations included the Bohai Rim area and the southern coastal areas.According to the local diagnosis criteria and the 2017 AHA/ACC guidelines,MOR was 1.82(95%CI:1.49-2.11)and 1.41(95%CI: 1.26-1.53)in the null multiple-level model,respectively.Regardless of the guidelines,smoking,alcohol consumption,overweight and obesity,and lack of physical activity were risk factors for hypertension,these lifestyle factors explained17.3%(PCV = 17.3%)and 30.0%(PCV = 30.0%)of the regional variation under the current Chinese guidelines and 2017 AHA/ACC guidelines,respectively.4.Geographical distribution of new diagnoses and the explanatory power of individual and regional variables on its geographic variation: The distribution of new diagnoses showed a clear gradient from north to south,with affected areas mainly concentrated in northern China.In the null model,MOR was 1.29(95%CI: 1.21-1.36).Among regional factors,the average annual temperature difference was the influencing factor of the regional variation,which could explain 11.6% of the regional variation(PCV = 11.6%).People in areas with larger annual temperature differences had a greater risk of new diagnosed,compared with the people lived in average annual temperature difference in the Q1 interval,those lived in an average annual temperature difference of Q2 and Q3 had a higher risk,the OR of which was 1.25(95%CI: 1.21-1.36)and 1.27(95%CI: 1.15-1.39)respectively.5.The relationship of CVD risk with blood pressure in different age groups: Among the middle-aged population,SBP = 140 mm Hg and DBP = 90 mm Hg indicated higher risks of CVD compared to the reference,OR was 1.19(95%CI: 1.03-1.37),1.21(95%CI:1.03-1.41)respectively,similar results were observed among elderly,OR was 1.13(95%CI: 1.05-1.22),1.40(95%CI: 1.26-1.56)respectively.Among the middle-aged population,under the2017 AHA/ACC guidelines,only stage 2 hypertension increased the risk of CVD with an OR of 1.36(95%CI: 1.13-1.64),in contrast,there was no correlation between stage 1hypertension and CVD,the OR of which was 1.10(95%CI: 0.94-1.28).In the elderly,both stage 1 and stage 2 hypertension under the 2017 AHA/ACC guidelines increased the risk of CVD the full-model,OR of which was 1.14(95%CI: 1.01-1.28)and 1.16(95%CI: 1.02-1.31),respectively.Conclusion1.The dimension with greatest concern by the Chinese medical workers is the impact of healthcare burden.2.If the 2017 AHA/ACC guidelines are implemented,the prevalence of hypertension in China will rise sharply.3.lifestyle factors can largely explain regional variation in the prevalence of hypertension,the intervention of individual behaviors is of great value for hypertension control in the provinces with high prevalence of hypertension,including the Bohai Rim and the southern coastal areas.4.The difference in annual average temperature,a regional factor,can somewhat explain the regional variation of the prevalence of new diagnoses,in areas with large annual average temperature differences,people have a higher risk.Therefor 2017 AHA/ACC guidelines are beneficial for early prevention of hypertension in areas with substantial annual temperature differences,such as northern China.5.The 2017 AHA/ACC guidelines are more applicable to the elderly population and the use of stricter criteria to monitor and control blood pressure in the elderly may help reduce the incidence of CVD.