Relation Of ACE Gene, CRP And Traditional Risk Factors With Cardio-cerebrovascular Diseases In Mongolian People

Objective:1. To investigate the association between traditional risk factors and hypertension among Mongolian population;2. To investigate the risk factors of cardio-cerebrovascular diseases among Mongolian population;3. To investigate the effects of C-reactive protein (CRP), ACE gene polymorphism and traditional risk factors on incidence of cardio-cerebrovascular diseases among Mongolian population.Subjects and methods:1. Baseline investigation: We conducted a cross-sectional study between 2002 and 2003 in Inner Mongolia, study participants aged 20 years and older were recruited from 32 villages in two adjacent townships located in Kezuohou Banner (county) and Naiman Banner.Data on demographic information, lifestyle risk factors, family history of hypertension and personal medical history were obtained using a standard questionnaire administered by trained staff,and body hight, weight, waist circumference,hip circumference and three times of blood pressures were measured for all participants. Fasting plasma glucose (FPG), triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), CRP, and ACE gene polymorphism were detected for all participants.2. Follow-up investigation: Follow-up investigations had been conducted for the subjects involved in baseline study for eight years. The study outcome was defined as incidence of the cardio-cerebrovascular events (including stroke and coronary heart disease incidence and death) in duration from baseline to final follow up.3. Statistical analysis: The Epidata3.0 Software was used to build database. SAS 9.1 and SPSS17.0 Software were used for statistical analysis, using P=0.05 as test level. Logistic analysis and decision tree methods were used to analyze the relations of C-reactive protein, ACE gene polymorphism and traditional risk factors and their interaction with prevalence of hypertension and incidence of cardio-cerebrovascular diseases among Mongolian population.Results1.A total of 2589 subjects aged 20-84 years old, 1064 males and 1525 females with average age of 46.51 years old( 20-84 years), were included in the study. There were 968 hypertensives and 1621 normotensives with prevalence of 37.39%。Multivariate logistic regression analysis showed that gender (female), old age, family history of hypertension, amount of smoking, volume of alcohol drinking, BMI, FPG and TG were associated with prevalence of hypertension, the ORs were 0.785、2.517,4.557,0.773,1.203,1.227,2.105,1.225 and 1.681,respectively. Log-linear model analysis showed that interaction between amount of smoking and years of smoking on hypertension was significant.2. Sigle factor analysis showed that ACE gene polymorphism related to levels of blood pressure(BP), the levels of systolic(131.02±25.90mmHg) and diastolic (85.26±13.20 mmHg)BP were significantly higher in the subjects with genotype ID than that in those with genotype DD(129.62±24.31; 84.60±12.79 mmHg), and higher in the subjects with genotype DD than that in those with genotype II(128.55±23.17; 83.76±12.23 mmHG)(p<0.05). The level of CRP related to prevalence of hypertension and prevalence of hypertension increased with elevated CRP, prevalence of hypertension in subjects with CRP<3.95, 3.95-11.38 and≥11.39mg/l was 29.7%, 32.5% and 46.9%, respectively.The level of CRP was higher in the subjects with genotype ID (10.26±10.14 mg/l)than that in those with genotype DD(9.32±9.48 mg/l) and genotype II(p<0.05).The results in decision tree analysis showed that age, family history of hypertension, WHR, drinking alcohol, years of smoking, BMI, CRP, TC and amount of alcohol drinking have great effects on systolic BP, and age, TG, family history of hypertension, BMI, WHR, volume of drinking alcohol, years of drinking, years of smoking, TC and CRP have great effects on diastolic BP. Interaction between old age and family history of hypertension on systolic BP was significant, and interaction between old age, overweight and volume of drinking on diastolic BP was significant.3. 2589 subjects were followed up for 18543.71 person-years, 146 cardio-cerebrovascular events occurred during period from baseline to final follow up, accumulation morbidity and incidence density for cardio-cerebrovascular events were 5.64% and 787.33/100,000 person-year, respectively. Incidence density for cardio-cerebrovascular events was 321.38/100,000 person-year in normotensives and 1607.25/100,000 person-year in hypertensives, respectively.The population with high risks for ischemic stroke was as follow according to the results of decision tree analysis:(1)the population with both high systolic and diastolic BP plus more than 5 years of drinking plus aged 60 years or more;(2)the population with both high systolic and diastolic BP plus less than 5 years of drinking plus aged 60 years or more;(3)the population with isolated high systolic BP plus aged 60 years or more.The population with high risk for hemorrhagic stroke was as follow according to the results of decision tree analysis:(1)the population with both high systolic and diastolic BP or isolated high systolic BP plus FPG>7.1mmol/l plus genotype II of ACE gene;(2)the population with both high systolic and diastolic BP isolated high systolic BP plus FPG>7.1mmol/l plus genotype ID of ACE gene;( 3 ) the population with normal BP and WHR plus heavy alcohol drinking(250ml/day).The population with high risk for coronary heart disease was as follow according to the results of decision tree analysis:Conclusions:The traditional risk factors including old age, family history of hypertension, heavy alcohol drinking,overweight and obesity,high FPG and high blood lipids were still important risk factors for hypertension; genotype ID of ACE gene related to elevated BP, and elevated CRP related to increased prevalence of hypertension; hypertension was most important risk factor of cardio-cerebrovascular diseases; the relationship between ACE gene and CRP and cardio-cerebrovascular diseases remained to be studied in future.