Study On The Risk Factors Of Cardiovascular And Cerebrovascular Disease And The Applicability Of Framingham Score Prediction In Mongolian Population

Introduction and Purpose1.To descript the charictristics of distribution of baseline cardiovascular risk factors among Mongolian population.2. To assess the relationship between diabetes or impaired fasting glucose and risk of cardiovascular events including stroke or coronary heart disease in the Mongolian population.3. Different hypertension subtypes probably have different prognostic implications as well as different effects on the future cardiovascular diseases, there have been no reports about the effects of hypertension subtypes on cardiovascular events among Mongolian people.4.To examine the association between interleukin-6(IL-6), von Willebrand factor(vWF), homocysteine (Hcy),endothelin-1(ET-1), intracellular adhesion molecule1(ICAM-1) and E-selectin and cardiovascular disease incidence by using nested case control study, based on prospective cohort of Mongolian population.5. The Framingham general cardiovascular disease (CVD) risk score (FGCRS) is a useful tool to identify individuals with a high risk for global CVD, however, there have been no report relating to the applicability of FGCRS for predicting CVD events among Mongolian population. This study aimed to validate the FGCRS in an Mongolian population, China.Subjects and Methods:1.2589Mongolian aged20years or over were selected as the participants, demographic characteristics and cardiovascular risk factors were collected, and the charictristics of distribution of baseline cardiovascular risk factors were descripted among Mongolian population.2.All participants were followed up to find cardiovascular events including new stroke and coronary heart disease. We analyzed the association of baseline fasting plasma glucose (FPG) and diabetes with cardiovascular events including stroke and coronary heart disease incidence. Cox proportional hazards models were used to calculate hazard ratios (95%confidence intervals).3. According to the baseline blood pressure levels, the subjects were divided into those with normal blood pressure, prehypertension, isolated systolic hypertension(ISH), isolated diastolic hypertension (IDH), and combined systolic and diastolic hypertension(SDH). Cox proportional hazards models were used to evaluate the association between hypertension subtypes and risk of cardiovascular diseases and calculate hazard ratios (HR)and95%confidence interval(95%CI).4. Based on a10-year follow-up prospective cohort study, we conducted a nested case control study on the participants. The new incident cardiovascular diseases including stroke and coronary heart disease were served as cases, and healthy persons whose age, gender, and residence site were matched to those of cases were served as controls, IL-6, vWF, Hcy, ET-1, ICAM-1and E-selectin at baseline were examined in the cases and control. According to tertiles of IL-6, vWF, Hcy, ET-1, ICAM-1and E-selectin, the participants were divided into three categories, and the participants with the highest tertile of the biomarkers were defined as increased biomarkers, and the others were defined as normal biomarkers. Logistic analysis were used to explore the relationship between the biomarkers increased and cardiovascular disease incidence, and calculate the odds ratio (OR) and95%CI.5.Based on cohort study of2589Mongolian participants, according to the Framingham formulation, a10-year risk of CVD was estimated for every participant. The performance of the FGCRS on predicting CVD was evaluated using Hosmer-Lemeshow test and C statistic in Mongolians. Attributable risk proportion were calculated to estimate the effectiveness of the FGCRS prediction.Results:1. The baseline characteristics of the participants.Average systolic blood pressure (SBP) and diastolic blood pressure (DBP)were129.8mmHg and84.5mmHg, respetively, for the Mongolian population; prevalence of hypertension was37.4%, and prevalence of hypertension was significantly higher for males (45.6%)than that for females (31.7%), P<0.01; prevalence of overweight (28>BMI≥24) and obesity (BMI≥28) were20.14%and6.69%, respectively, for males and females, prevalence of overweight (16.8vs.22.5%) and obesity(5.2vs.7.7%) were lower for males than those for females, all P<0.05. Smoking rate was44.4%among the Mongolian population, the smoking rate (64.0%) was significantly higher for males than that (30.8%)for females, P<0.01; rate of alcohot drinking was33.5%, the drinking rate (64.0%) was significantly higher for males than that (11.7%) for females, P<0.01. The prevalence of high TC, high TG and high FPG were10.2%,17.5%and21.94%, respectively.2. The impact of impaires fasting plasma glucose on cardiovascular events in Mongolian population.After adjustment for age, smoking, drinking, SBP, SDP, BMI, CRP and dyslipidemia, the HR(95%CI) of cardiovascular events (stroke and coronary heart disease) were2.71(1.68,4.37) for diabetes, compared with nondiabetes; the HR(95%CI) of stroke were2.04(1.01,4.13) for diabetes, compared with nondiabetes, the HR(95%CI) of coronary heart disease were3.78(1.95,7.33) for diabetes, compared with nondiabetes.3. Association of hypertension subtypes with cardiovascular events among Mongolian people.After adjustment for age and gender, hazard ratios (95%confidence intervals) of cardiovascular diseases were1.75(0.92-3.33),2.11(0.95-4.70),2.14(1.01-4.56) and5.31(2.86-9.77) for pre-hypertension, ISH,IDH and SDH, respectively, compared with normal blood pressure. Furthermore, after adding other cardiovascular risk factors to adjustment, hazard ratios(95%confidence intervals) of cardiovascular diseases were1.78(0.92-4.60),2.06(0.92-4.60),2.16(1.01-4.63) and5.19(2.77-9.72) for pre-hypertension, ISH, IDH and SDH, respectively, compared to normal blood pressure.4. Nested case control study on association of imflammation biomarkers with cardiovascular diseases.Compared with Hcy<14.19umol/L, ICAM-1<409.87ng/ml, ET-1<0.75ng/L, E-seletin<18.13ng/ml (normal levels), no matter whether covariables were adjusted or not, the ORs of cardiovascular disease incidence for Hcy≥14.19umol/L, ICAM-1≥409.87ng/ml, ET-1≥0.75ng/L and E-seletin≥18.13ng/ml were not significnt. However, compared with vWF<13.86pg/1(normal level), the OR (95%CI) of cardiovascular disease incidence for vWF≥13.86pg/1was1.542(0.922,2.577) with a border statistically significance,after adjustement for multivariables, the OR (95%CI) of cardiovascular disease incidence for vWF≥13.86was2.369(1.25,4.493),the OR was statistically significant. Similarly, compared with IL-6<24.63pg/ml (normal level),the OR (95%CI) of cardiovascular disease incidence for IL-6≥24.63pg/ml was1.634(1.009,2.647), the OR was statistically significant.5. Utility of Framingham General Cardiovascular Disease Risk Score for predicting cardiovascular risk among Mongolian population.There were23,292person-years of follow-up, and200CVD events were observed. The predicted risk of CVD events (8.52%) was close to the observed risk of CVD events (7.72%,95%CI:6.73%-8.82%). The FGCRS had a good calibration (Hosmer-Lemeshow test:Χ2=9.22, P=0.324) and a good discrimination (C statistic:0.81,95%CI:0.78-0.84) in the Mongolian population. Participants were divided into four groups based on their predictive risk scores:0-4.9%(reference),5-9.9%,10-19.9%, and≥20%. Attributable risk proportion of CVD events for the participants with the predictive risk scores of5-9.9%,10-19.9%, and≥20%were61.39%,79.04%and83.66%, respectively.Conclusions:1.The prevalence of some cardiovascular risk factors such as hypertension, overweight/obesity,smoking, drinking, dyslipidemia as well as high FPG were higher among the Mongolian population.2.Diabetes was a independent risk factor of cardiovascular disease among Mongolian population, this study suggest that actively treating the subjects with diabetes and controling FPG should be an important strategy for cardiovascular disease prevention.3.IDH and SDH were significantly associated with the increased risk of cardiovascular diseases, this study suggests that that carefully monitoring and actively treating the subjects with IDH should be an important strategy for CVD prevention among Mongolian population.4. vWF and IL-6were independent risk factors of cardiovascular disease incidence.5.The observed risk of CVD events was close to the predicted risk of CVD events from FGCRS among the participants, the FGCRS can be used to predict CVD events among Mongolians in China.