Validation and generalizability of the predictive model of ischemic cardiovascular diseases in Chinese / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the applicability of developed prediction models of ischemic cardiovascular diseases (ICVD) in Chinese to other Chinese populations.</p><p><b>METHOD</b>We used the independent prospective cohort established in early 1990's from China Multi-Center Collaborative Study of Cardiovascular Epidemiology (MUCA), as the validation cohort, to test the hypothesis. The area under ROC curve (AUC) based on the application of the Cox optimal model and the simplified model to the validation cohort were calculated and to test the ability of the prediction models to discriminate events from nonevents. Applicability was evaluated by comparing the mean probability estimates in each decile of probability in the validation cohort with the observed incidence with the Hosmer-Lemeshow test.</p><p><b>RESULTS</b>The validation cohort enrolled a total of 17 329 men and women aged 35 to 59 years baseline 1992 - 1994. In this paper, we used data from the remaining 15 100 participants after excluding 2229 subjects for at missing value of risk factors. During 11-year follow up of the cohort, there were 347 ICVD events (206 for men and 141 for women), including 83 coronary heart disease events (56 men and 27 women) and 268 ischemic strokes (154 men and 114 women). ROC curves for men and women showed good and almost identical discrimination for optimal model (the AUCs (95% CI) were 0.796 (0.762 - 0.829) for men and 0.791 (0.755 - 0.828) for women), simplified model (the AUCs (95% CI) were 0.792 (0.758 - 0.825) for men and 0.783 (0.746 - 0.821) for women) and score system (the AUCs (95% CI) were 0.791 (0.757 - 0.825) for men and 0.779 (0.741 - 0.817) for women) in the validation cohort. The predicted 10-year risk of ICVD by optimal models and observed incidence of ICVD in the validation cohort in each decile were compared. Hosmer-Lemeshow chi2 was 3.7 for men (P = 0.879) and 27.7 for women (P < 0.001). Whereas the largest difference between the observed rate and the predicted rate was only 1%.</p><p><b>CONCLUSIONS</b>The prediction models for estimating 10-year risk of ICVD had satisfied predictive capability when they were applied to the validation cohort and are applicable to other Chinese populations.</p>

Cut offs and risk stratification of dyslipidemia in Chinese adults / 中华心血管病杂志

<p><b>OBJECTIVE</b>To establish cut offs and risk stratification of dyslipidemia in Chinese adults.</p><p><b>METHODS</b>Data from 2 widely cited studies: the PRC-US Collaborative Study of Cardiovascular and Cardiopulmonary Epidemiology and the China Multi-Provincial Cardiovascular Cohort Study, with a total of 40 719 Chinese adults, age 35 to 64 at baseline, about half men and half women, followed up for a total of 345 140.5 person years, were used to analyze the relationship between dyslipidemia and ischemic cardiovascular diseases (ICVD, including coronary heart events and ischemic stroke events) using a common data analysis protocol co-developed by the scientists from the 2 studies. The relative risk was estimated with the Cox proportional hazard model adjusting for other conventional cardiovascular risk factors. The 10-year absolute risk of ICVD for a 50 years-old person at different risk factor combinations was used to develop the risk stratification.</p><p><b>RESULTS</b>(1) There was a continuous linear relationship between baseline TC (or LDL-C) and ICVD risk without a threshold; (2) The incidence (absolute risk) of ICVD was similar for LDL-C < 3.37 mmol/L (130 mg/dl) and for TC < 5.18 mmol/L (200 mg/dl); and similar for LDL-C < 4.14 mmol/L (160 mg/dl) and for TC < 6.22 mmol/L (240 mg/dl); (3) The absolute ICVD risk for TC > or = 6.22 mmol/L (240 mg/dl) was slightly less but close to that for grade 1 hypertension; (4) ICVD risk increased as HDL-C decreased; (5) No significant association was found between baseline TG and subsequent ICVD; (6) At any TC level, the absolute ICVD risk for those having only hypertension was higher than that for those having 3 other risk factors.</p><p><b>CONCLUSION</b>The cut offs for diagnosis of dyslipidemia in Chinese adults can refer to those used in relevant international guidelines: TC < 5.18 mmol/L (200 mg/dl) [or LDL-C < 3.37 mmol/L (130 mg/dl)] as normal, TC 5.18 - 6.19 mmol/L (200 - 239 mg/dl) [or LDL-C 3.37 - 4.12 mmol/L (130 - 159 mg/dl)] as borderline high, and TC > or = 6.22 mmol/L (240 mg/dl) [or LDL-C > or = 4.14 mmol/L (160 mg/dl)] as high; HDL-C < 1.04 mmol/L (40 mg/dl) as low, 1.04 - 1.53 mmol/L (40 - 59 mg/dl) as normal and > or = 1.55 mmol/L (60 mg/dl) as optimal. In risk stratification scheme, hypertension plays a role that equals to that of any other 3 risk factors.</p>

Study on the baseline physical activity and the risk of ischemic cardiovascular diseases / 中华流行病学杂志

<p><b>OBJECTIVE</b>To examine the associations between physical activity measures [metabolic equivalents of energy expenditure (MET) per hour per day] and ischemic cardiovascular diseases (ICVD) in Chinese population.</p><p><b>METHODS</b>A survey on cardiovascular risk factors was conducted in different areas of China in fall 1998. People aged 35 to 59 but without a history of coronary heart and stroke at baseline were prospectively followed and 11 849 subjects whose information were complete at the end of second follow-up were valid. Cox regression was used to estimate the hazard ratios (HRs) for incident ischemic cardiovascular diseases and the different measures of physical activity.</p><p><b>RESULTS</b>During a mean follow-up period of 5.9 years, 84 incident ischemic cardiovascular events were ascertained. We examined the HRs of ischemic cardiovascular events for a 1-unit change in METs value, which were included in the models as continuous variable. There were negative association of METs values found with ischemic cardiovascular events in total, urban, rural, male and female subjects, and statistical significance in the urban (HRs = 0.22, 95% CI: 0.05-0.95) but the association was weakened after adjustment for demographic factors. When further adjustment for other intermediate factors, the significance in the urban was again attenuated. When the urban males and females, rural males and females were divided into 3 groups according to their respective tertiles and the combination of different population groups, the factors of male/female and urban/ rural were equally distributed in different groups, and no more adjustment in the Cox model. The multivariate - adjusted (age and education attainment) HRs associated with the tertiles, from lowest to highest, were: 1, 1.03 and 0.65 (P(trend) = 0.170) for the total, 1, 0.72 and 0.64 for the urban, 1, 1.49 and 0.72 for the rural, 1, 1.05 and 0.59 for men, 1, 0.90 and 0.84 for women.</p><p><b>CONCLUSION</b>The totality of our findings pointed to METs per hour per day seemed to be weakly associated with a reduction in ischemic cardiovascular events incidence among urban middle-aged adults.</p>

A cohort study on parental history of hypertension and the risk of cardiovascular disease in Chinese population / 中华心血管病杂志

<p><b>OBJECTIVE</b>To assess the relationship between parental history of hypertension and the incidence of cardiovascular disease in Chinese populations.</p><p><b>METHODS</b>A total of 15 131 individuals (7015 men and 8116 women, aged from 35 to 59 years) in China were enrolled and followed up from 1992 to 2005. The information on the parental history of hypertension of the participants was collected. The individuals were divided into three groups according to their parental history of hypertension: those without parental history of hypertension (group 1), those with one parent history of hypertension (group 2) and those with both parents history of hypertension (group 3). The hazard ratio and its 95% confidence interval were calculated using the Cox proportional hazard model.</p><p><b>RESULTS</b>There were 448 cardiovascular events (including 82 cardiac events and 370 stroke events and 4 with both cardiac and stroke events) during the 163 858 person-years of observation. After adjusting for age, smoking and drinking, the hazard ratio for cardiovascular disease for group 1, group 2 and group 3 were 1.00, 1.34 (1.01 - 1.78), 2.58 (1.62 - 4.11) in men respectively and 1.00, 1.77 (1.27 - 2.45), 2.55 (1.44 - 4.54) in women respectively. After further adjusting for serum total cholesterol (TC), high density lipid cholesterol (HDL-C), fasting glucose, body mass index (BMI) and systolic blood pressure (SBP) in the model, the hazard ratio for cardiovascular disease for those three groups were 1.00, 1.01 (0.76 - 1.35), 1.72 (1.07 - 2.75) in men respectively and 1.00, 1.31 (0.94 - 1.84), 1.76 (0.98 - 3.15) in women respectively.</p><p><b>CONCLUSION</b>The individuals with parental history of hypertension have a higher risk of cardiovascular disease, especially for those with both parents history of hypertension.</p>

The current status on the prevalence, awareness, treatment and control of diabetes mellitus in several Chinese subpopulations / 中华流行病学杂志

<p><b>OBJECTIVE</b>To determine the prevalence of impaired fasting glucose (IFG), diabetes mellitus(DM), rates of awareness, treatment and control of DM in 14 Chinese subpopulations and the trends of development in recent years.</p><p><b>METHODS</b>We collected data on history regarding DM and fasting serum glucose in 14 Chinese subpopulations aged 35 to 59 in 1998, under cluster sampling. In 4 out of the 14 subpopulation samples, a similar survey using same methods in 1993 - 1994 was carried out. IFG and DM were diagnosed according to the WHO criteria.</p><p><b>RESULTS</b>The age-standardized prevalence rates of IFG and DM were from 0.5% to 15.6% (mean: 4.8%) and from 0.2% to 10.6% (mean: 4.3%) for the whole 14 subpopulations in 1998 which were not different between men and women, but higher in urban than in rural (P < 0.01), but increased with age (P < 0.01). The rates of awareness,treatment and control of DM were from 0% to 46.2% (mean: 33.3%), from 0% to 46.2% (mean: 27.2%), and from 0% to 15.4% (mean: 9.7%), which were significantly higher in women than in men (P < 0.01), higher in urban than in rural (P = 0.031), and higher in older participants (P < 0.05), but not much different in the levels of education. The rate of treatment in patients with awareness of DM and the rate of control in patients with treated DM were 81.6% and 35.6% respectively, which were not different between men and women, urban and rural or among different age groups. The mean prevalence of DM increased from 3.8% in 1993 - 1994 to 4.6% in 1998 (P = 0.037). The rates of awareness, treatment and control of DM had an increasing trends but with no significant differences between years 1993 - 1994 and 1998.</p><p><b>CONCLUSION</b>The prevalence of DM in 14 Chinese subpopulations exhibited no differences between men and women, but showing significant differences among areas and an increasing trend in the recent years. The rates of awareness, treatment, and control were still relatively low. To improve the efficacy of screening program and treatment seemed to be the two key issues in prevention and control of DM in China.</p>

The development and Assessment on the general quality of life intrument for Chinese people / 中华流行病学杂志

<p><b>OBJECTIVE</b>To develop a general quality of life (QOL) instrument for Chinese in accordance with the Chinese culture and to assess its reliability, validity and sensitivity.</p><p><b>METHODS</b>A 35-item QOL questionnaire(QOL-35) was developed with reference to the World Health Organization QOL questionnaire(WHO-100) and the 36-item medical outcomes study on short-form health status(SF-36). Thirty five items were divided into six domains (general, physical, independent, psychological, social, environment) and one item on QOL transition. The reliability of QOL-35 was assessed by a test-retest survey among 127 adults with an interval of 24-72 hours. The internal consistency and validity were evaluated by a survey on 135 adults from outpatients or general population, using QOL-35, WHO-100 and SF-36. The adaptability was assessed by application to 1356 community-based samples in Beijing.</p><p><b>RESULTS</b>(1)Test-retest reliability of QOL-35: weighted Kappa indexes for items were from 0.86 to 1.00. Intraclass correlation coefficients were from 0.68 to 0.94 for domains, and 0.94 for total score. (2) On internal consistency: Cronbach's Alphas were 0.93, 0.97 and 0.89 for QO1-35, WHO-100 and SF-36. (3)On construct validity. The accumulated proportions of variances of the preceding seven factors were 66.5%, 50.3% and 65.3% for QOL-35, WHO-100 and SF-36. (4) On criterion validity. Spearman correlation coefficients of total QOL score of QOL-35 with those of WHO-100 and SF-36 were 0.805 and 0.745. (5)The rates of chronic diseases were 53.1%, 33.1%, 26.4% and 25.1% from first to fourth quantile of the total QOL scores of QOL-35(P<0.05). (6)Cronbach's Alpha was from 0.68 to 0.93 in 135 subjects, and from 0.71 to 0.91 in 1356 individuals of natural population.</p><p><b>CONCLUSION</b>The QOL-35 instrument satisfied test-retest reliability and was highly correlated with WHO-100 and SF-36, having fewer items but better construction validity, better internal consistency, and better discrimination ability. We suggested that QOL-35 be used as a replicable tool to assess quality of life in the Chinese general population.</p>

Dietary treatment and success rate of control in hypercholesterolemia patients treated with lipid lowering drugs: a multi-center study of current status on clinical control of hypercholesterolemia in China / 中华心血管病杂志

<p><b>OBJECTIVE</b>To assess the current status in dietary treatment of hypercholesterolemia and its effects on control of this disease in China.</p><p><b>METHODS</b>Twenty five Tertiary-A hospitals from 12 provinces in China were selected, in which 2136 patients were recruited who had had hypercholesterolemia and had been receiving lipid lowering treatment for at least 2 months. Serum lipids level was determined for each patient at the time of enrollment, and using a simplified food frequency method carried out dietary intake survey. Patients who take meat of less than 75 g per day and eggs of less than 5 per week, and fried foods of less than 5 times per week, and butter cakes and pastry of less than 5 times per week were considered as having their diet controlled.</p><p><b>RESULTS</b>Among 1746 responded patients, 68.3% reported having controlled diet. Among those reported "controlled", 75% had a diet meeting the requirements suggested by the Chinese Recommendations on Prevention and Treatment of Hypercholesterolemia (CRPTH). The percentage of patients having their serum total cholesterol under control in diet controlled group, according to the CRPTH, was significantly higher than that in diet uncontrolled group (28.8% vs 13.6%, P < 0.01). After adjustment for drug treatment and other covariates, the diet controlled group showed a significantly higher rate in control of hypercholesterolemia than the diet uncontrolled group (OR = 2.7, 95% CI: 1.4 approximately 5.2).</p><p><b>CONCLUSION</b>Diet control significantly improves the status in control of hypercholesterolemia and thus should be reinforced in routine clinical practice.</p>

The cut-off point of waist circumference for identifying metabolic syndrome in Chinese adults / 中华心血管病杂志

<p><b>OBJECTIVE</b>Metabolic syndrome has attracted more attention from scientists of related areas due to its association with increased risk of cardiovascular disease and diabetes. The clinical identification criteria for metabolic syndrome issued by ATP III of NECP indicate the enlarged waist as the first component using the cut-offs derived from Caucasians. The purpose of this study is to investigate the appropriate cut-offs of waist circumference for Chinese adults as a component of metabolic syndrome.</p><p><b>METHODS</b>Database of 13732 Chinese adults with 35 - 59 years from the risk factor survey in 1998 (the 9(th) Five Year National Project on trends and prediction of cardiovascular disease) was used to analyze the ORs of clustering of risk components by different strata of waist circumference. The sensitivity, specificity and distance in ROC curve by different cut-offs of waist circumference for identifying two or more risk components of metabolic syndrome were estimated to find the cut-off point for men and women with the shortest distance in ROC curve.</p><p><b>RESULTS</b>The ORs of clustering of risk components increased significantly with the size of waist circumference. The waist circumference (>/= 85 cm for men, >/= 80 cm for women) corresponded to the shortest distance in ROC curve, namely, at these cut-offs, the rates of false positive and false negative for identifying clustering of two or more risk components were the minimum.</p><p><b>CONCLUSIONS</b>If a person had three or more of the following components, metabolic syndrome could be defined: waist circumference >/= 85 cm in men or >/= 80 cm in women, SBP >/= 130 mm Hg or DBP >/= 85 mm Hg, TG >/= 1.69 mmol/L, HDL-C < 1.03 mmol/L and fasting blood glucose >/= 6.1 mmol/L. The prevalence of metabolic syndrome was 19.3% and 13.9% in middle-aged men and women respectively. In these patients the combination of enlarged waist, high blood pressure and high TG was the most frequent. This recommendation need further confirmed in representative sample of Chinese population.</p>

A cohort study on the relationship between nutrients intake and the incidence of hypertension in middle-aged Chinese / 中华心血管病杂志

<p><b>OBJECTIVE</b>To explore the relationship between nutrient intake and the incidence of hypertension in middle-aged Chinese.</p><p><b>METHODS</b>A prospective study was conducted in 653 men and women of Beijing and Guanzhou, aged 35-59 years. The subjects had no hypertension or other cardiovascular diseases at baseline risk factor and dietary survey carried out in 1983-1984. The baseline information of nutrient intake was collected by using a 24-hour recall method on three consecutive days. The incidence of hypertension was determined through the follow-up survey in 1993-1994. The subjects were categorized into three groups according to tritiles of each baseline nutrient intake and the relative risk for hypertension incidence in each group was calculated by using the logistic regression model with the group of lowest risk as the referent.</p><p><b>RESULTS</b>During the period of 1983-1984 to 1993-1994, 170 among 653 subjects had developed hypertension; 92 were men and 78 were women. After adjustment for other risk factors, the relative risk of hypertension for different protein intake groups was 1.0, 0.87 (95% CI 0.54-1.40) and 0.52 (95% CI 0.32-0.87), respectively, and the p value for trend analysis was 0.011; the relative risk of hypertension for different sodium intake groups was 1.0, 1.12 (95% CI 0.66-1.88) and 1.85 (95% CI 1.09-3.14), respectively, and the p value for trend analysis was 0.015. There was no significant relationship between the other nutrient intake and hypertension incidence.</p><p><b>CONCLUSION</b>Among middle-aged Chinese, protein and sodium may be two of the most important dietary factors affecting the incidence of hypertension. Increasing protein intake and reducing sodium intake might be helpful for the prevention of hypertension.</p>

Trends in prevalence, awareness, treatment and control of hypertension in middle-aged Chinese population / 中华流行病学杂志

<p><b>OBJECTIVE</b>To analyze the trends in prevalence, awareness, treatment, control of hypertension among middle-aged Chinese.</p><p><b>METHODS</b>The study comprised two cross-sectional surveys including urban and rural residents, manual workers, farmers and fishermen in different southern and northern parts of China. There were 13 populations under research with comparable data. 18 746 (in 1992 - 1994) and 13 504 (in 1998) participants, aged 35 through 59 years, equal number of men and women, were examined in each of the surveys, on blood pressure measurement, in 1992 - 1994 and in 1998. Hypertension was defined as systolic pressure >/= 140 mm Hg, and/or diastolic pressure >/= 90 mm Hg, and/or reported treatment with antihypertensive medications. Awareness and treatment on hypertension were assessed with standardized questions. Hypertension control was defined as measured blood pressure of less than 140/90 mm Hg. Awareness, treatment and control of hypertension were standardized according to the WHO world standard population.</p><p><b>RESULTS</b>In 1998, 24.0% of participants had hypertension, an increase of 2.3% from 1992 - 1994. Prevalence of hypertension was higher in urban area (25.4%), increasing with age, and higher in men among the younger groups and lower in women among the older groups. Overall, in 1998, 42.6% were aware of their hypertensive status (increase of 5.3%), 31.3% were treated (increase of 3.8%), and the rate under control was 6.0% (increase of 2.6%). The rates of awareness, treatment and control, which tended to increase with age except those aged above 55 years, which were higher in urban areas and women compared with rural areas and men. For people with treated hypertension, the rates of those under control were ranged from 12.7% in 1992 - 1994, to 19.9% in 1998.</p><p><b>CONCLUSION</b>Prevalence of hypertension was increasing in China, while the rates of control, although improving, continued to be low. This implied that effective public measures needed to be developed to enhance the awareness and rates of treatment.</p>

A study on the association between tea consumption and stroke / 中华流行病学杂志

<p><b>OBJECTIVE</b>The aim of the study was to investigate the association between tea consumption and stroke.</p><p><b>METHODS</b>A cross sectional study was conducted in autumn, 1998. The subjects were from 12 provinces in China. 15 groups of populations were selected by cluster randomized sampling and each group had about 1000 persons, aged from 35 to 60 years old. 14 212 subjects had complete data for analysis. Data regarding tea drinking would include drinking status, dose and type of teas. Logistic regression was used to analyze the association between tea consumption and stroke.</p><p><b>RESULTS</b>There was a strong inverse correlation between tea drinking and stroke after adjusting other risk factors of stroke (P < 0.05). The odds ratio (OR) of stroke was 0.60 [95% confidence interval (CI): 0.42 - 0.85] for subjects who drank tea compared to those who did not. Increased amount of tea consumption per month was associated with decreased stroke prevalence. The association for tea consumption over 150 gram per month and stroke was statistically significant (P < 0.05) with an OR value of 0.56 (95% CI: 0.36 - 0.89). Analytical results indicated that the OR value was 0.24 (95% CI: 0.06 - 1.01) for black tea and other tea (P = 0.05). The OR value was 0.35 (95% CI: 0.18 - 0.72) for green tea (P < 0.01), and 0.75 (95% CI: 0.51 - 1.11) for jasmine tea (P > 0.05).</p><p><b>CONCLUSION</b>Tea drinking was independently associated with prevalence of stroke which might play a role in the prevention of the disease.</p>

Alcohol consumption and incidence of ischemic stroke in male Chinese / 中华流行病学杂志

<p><b>OBJECTIVE</b>To assess the relationship between incidence of ischemic stroke and alcohol consumption.</p><p><b>METHODS</b>The information on alcohol consumption and other cardiovascular risk factors such as SBP, DBP, TC was collected among 10 populations in northern and southern parts of China according to the international standardized methods. A total number of 30 560 men and women aged 35 - 59 were enrolled and followed up for an average of 15.2 years. Complete data on 12,352 men was analyzed.</p><p><b>RESULTS</b>The risk on ischemic stroke incidence showed a graded association. Compared with nondrinkers, the relative risks of incidence of ischemic stroke for those who drank alcohol less then 15 gram per day, 15-30 gram per day, 30-60 gram per day, above 60 gram per day were 0.86 (95% confidence interval 0.57-1.27), 1.20 (0.87-1.65), 1.26 (0.86-1.84) and 1.96 (1.30-2.93), respectively.</p><p><b>CONCLUSION</b>Our study revealed that in male Chinese, heavy alcohol intake significantly increased the risk while mild alcohol drinking did not increase the risk of ischemic stroke.</p>

Relation of body mass index and waist circumference with clustering of other risk factors for cardiovascular disease / 中华预防医学杂志

<p><b>OBJECTIVE</b>To assess the relationship of body mass index (BMI) and waist circumference (WC) with clustering of other risk factors for cardiovascular disease (CVD).</p><p><b>METHODS</b>A total of 30 561 participants aged 35 - 59 from different parts of China were surveyed for risk factors of CVD in two independent cross-sectional studies carried out in 1992 - 1994 and 1998. Data were pooled to analyze clustering rate of risk factors for CVD and relative risk of their clustering at varied levels of BMI and WC. Clustering of other risk factors for CVD was defined as any participant who had any two or more risk factors, such as high blood pressure, high serum total cholesterol, low HDL-C, high fasting plasma glucose. Clustering rate of other risk factors for CVD at different levels of BMI and WC was estimated.</p><p><b>RESULTS</b>Clustering rate of other risk factors for CVD significantly increased with rising of BMI and WC. In most of varied BMI groups, clustering rate of other risk factor increased with rise of WC in both men and women (P value for trend < 0.05), and in most of varied WC groups, clustering rate of other risk factor significantly increased with rise of BMI (P value for trend < 0.05). Clustering rate of other risk factors for CVD adjusted for age was 11.1% and 10.4% with BMI < 24.0 kg/m(2) and WC < 85/80 cm, 24.0% and 17.0% with BMI of 24 - 27.9 kg/m(2) and WC < 85/80 cm, 34.3% and 24.0% with BMI of 24 - 27.9 kg/m(2) and WC of 85 - 95.9/80 - 89.9 cm, 40.8% and 29.6% with BMI of 24 - 27.9 kg/m(2) and WC >/= 95/90 cm, 44.2% and 29.9% with BMI >/= 28 kg/m(2) and WC of 85 - 95.9/80 - 89.9 cm, and 54.7% and 35.4% with BMI >/= 28 kg/m(2) and WC >/= 95/90 cm, for men and women, respectively.</p><p><b>CONCLUSIONS</b>BMI and WC were independently and positively associated with clustering rate of other risk factors for CVD. It is very important for health to keep both BMI and WC in normal level.</p>

Mean level of blood pressure and rate of hypertension among people with different levels of body mass index and waist circumference / 中华流行病学杂志

<p><b>OBJECTIVE</b>To assess the relationship between body mass index (BMI), waist circumference (WC) and blood pressure (BP) including hypertension.</p><p><b>METHODS</b>A total of 30 003 participants aged 35 - 59 from different parts of China were surveyed for cardiovascular disease risk factors in two independent cross-sectional studies that were carried out in 1992 - 1994 and in 1998. Data were pooled to analyze the levels of BP and rates of hypertension with different levels of BMI and WC.</p><p><b>RESULTS</b>The level of BP and rate of hypertension were significantly increasing with rising of WC among the majority of BMI groups (P value for trend < 0.05) and significantly increasing with rising of BMI in all WC groups (P value for trend < 0.05). The age adjusted hypertension rate with BMI < 24.0 kg/m(2) and WC < 85/80 cm (men/women), BMI < 24.0 kg/m(2) and WC >or= 85/80 cm (M/W), BMI 24.0 - 27.9 kg/m(2) and WC < 85/80 cm (M/W), BMI 24.0 - 27.9 kg/m(2) and WC >or= 85/80 cm (M/W), BMI >or= 28 kg/m(2) and WC >or= 85/80 cm (M/W) were 16.5%, 29.8%, 29.6%, 39.2% and 57.5% for men and 14.1%, 20.6%, 24.7%, 30.3% and 43.3% for women, respectively.</p><p><b>CONCLUSION</b>Independent influence of BMI or WC on BP was noticed. Keeping BMI and WC at normal level might effectively prevent the occurrence of hypertension.</p>

An evaluation on effectiveness of worksite-based intervention for cardiovascular disease during 1974 - 1998 in capital iron and steel company of Beijing / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the feasibility and effectiveness of worksite-based cardiovascular disease (CVD) prevention and control program in urban population of China.</p><p><b>METHODS</b>Worksite-based intervention program was implemented 110 000 employees at Capital Iron and Steel Company of Beijing (CISC) focusing on primary prevention for CVD and control of hypertension. Intervention components comprised of infrastructure setting-up, health education and health promotion, professional training, detection and management of hypertensive patients, and reasonably readjusting their diet structure focusing on salt intake reduction, reducing their overweight, quitting smoking, and restricting alcohol consumption in high-risk population. Changes in level of risk factors, incidence and mortality of stroke and coronary events and their trend were evaluated between the intervention group at CISC and eight simultaneously parallel reference groups in other provinces outside Beijing with population surveillance data.</p><p><b>RESULTS</b>Major risk factors for CVD, including blood pressure, body mass index and serum cholesterol level, decreased relatively in intervention population at CISC during 1974 to 1998, while those in majority of eight parallel reference groups at different provinces of China significantly increased at the same time. Systolic blood pressure (SBP) decreased by 0.8 mm Hg and 4 mm Hg in average for men and women, respectively, and their diastolic blood pressure (DBP) remained the same as baseline for both men and women at CISC, while SBP increased by (2 - 11) mm Hg and (6 - 8) mm Hg in average for men and women, respectively in reference groups, and DBP increased by (2 - 6) mm Hg in average for men in five of eight reference groups, and by (3 - 6) mm Hg for women in four of eight reference groups. Serum level of cholesterol decreased by 0.26 mmol/L in women and slightly increased for men at CISC, and increased by (0.35 - 0.97) mmol/L for men and (0.29 - 1.05) mmol/L for women in all reference groups. Prevalence of overweight increased by 58.7% for men and 11.3% for women at CISC and increased by one to 22 folds in eight reference groups. Awareness of health knowledge improved significantly with an average net reduction of SBP/DBP of (2.5/2.2) mm Hg in the enforced intervention group at CISC than that in general intervention groups. Incidence and mortality rates of stroke decreased by 54.7% and 74.3%, respectively in intervention group at CSIC, but those of coronary events slowly increased with fluctuation.</p><p><b>CONCLUSION</b>Worksite-based comprehensive intervention for CVD prevention and control was feasible and cost-effective in decreasing risk factors for CVD, incidence and mortality rate of stroke in population of urban areas of China.</p>

A forty-year study on hypertension / 中国医学科学院学报

Since 1959 the investigations on prevalence of hypertension and studies on the prevention and treatment of this disease have been carried out. The vascular mechanism of hypertension and the depressor effect of Chinese traditional herbs were also studied in Chinese Academy of Medical Sciences. The results revealed that: (1) The prevalence of hypertension in Chinese adults increased from 7.73% in 1979 to 11.26% in 1991, both much higher than that in 1959 (5.11%). The rate of awareness, treatment and control was only 26.3%, 12.1%, and 2.8% respectively. The risk factors of hypertension included overweight and alcohol drinking. High sodium, low potassium, low calcium, and low animal protein diet were also very important risk for elevation of blood pressure. Hypertension was the most important causal risk factor of coronary heart disease and stroke. (2) Hypertension diagnosis and staging criteria were established in 1959. Secondary hypertension was found to constitute 1.1% among community hypertensive patients. The new concept of aortitis was formed and found to be the most common cause of renal vascular hypertension. Patient education together with low dose compounds of antihypertensive drugs was implicated widely. Randomized clinical trials Syst-China, Post-stroke Antihypertensive Treatment Study, Chinese Acute Stroke Trial, and Chinese Cardiac Study 1 demonstrated benefits of treatment for hypertensive, stroke or acute myocardial infarction affordable by Chinese population at large. (3) A series of functional changes and abnormalities with evident hereditary characteristics were found in the processes of cellular Ca2+ transportation, utilization, metabolism and their modulation of the vascular smooth muscle in SHR, and SHRsp, which seem to be the principal cause of the increase in peripheral vascular resistance in hypertension. (4) Alkaloid of Rauwolfia verticilata and Ligustrazine had marked depressor effect. Flavones of Radix Pueraricae could reduce the cardiac and cerebral ischemic damage and symptoms in hypertensive patients.

Predictive values of body mass index and waist circumference for risk factors of certain related diseases in Chinese adults--study on optimal cut-off points of body mass index and waist circumference in Chinese adults / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>For prevention of obesity in Chinese population, it is necessary to define the optimal range of healthy weight and the appropriate cut-off points of BMI and waist circumference for Chinese adults. The Working Group on Obesity in China under the support of International Life Sciences Institute Focal point in China organized a meta-analysis on the relation between BMI, waist circumference and risk factors of related chronic diseases (e.g., high diabetes, diabetes mellitus, and lipoprotein disorders).</p><p><b>METHODS</b>13 population studies in all met the criteria for enrollment, with data of 239,972 adults (20-70 year) surveyed in the 1990s. Data on waist circumference was available for 111,411 persons and data on serum lipids and glucose were available for more than 80,000. The study populations located in 21 provinces, municipalities and autonomous regions in mainland China as well as in Taiwan. Each enrolled study provided data according to a common protocol and uniform format. The Center for data management in Department of Epidemiology, Fu Wai Hospital was responsible for statistical analysis.</p><p><b>RESULTS AND CONCLUSION</b>The prevalence of hypertension, diabetes, dyslipidemia and clustering of risk factors all increased with increasing levels of BMI or waist circumference. BMI at 24 with best sensitivity and specificity for identification of the risk factors, was recommended as the cut-off point for overweight, BMI at 28 which may identify the risk factors with specificity around 90% was recommended as the cut-off point for obesity. Waist circumference beyond 85 cm for men and beyond 80 cm for women were recommended as the cut-off points for central obesity. Analysis of population attributable risk percent illustrated that reducing BMI to normal range (< 24) could prevent 45%-50% clustering of risk factors. Treatment of obese persons (BMI > or = 28) with drugs could prevent 15%-17% clustering of risk factors. The waist circumference controlled under 85 cm for men and under 80 cm for women, could prevent 47%-58% clustering of risk factors. According to these, a classification of overweight and obesity for Chinese adults is recommended.</p>

Effect of body mass index on all-cause mortality and incidence of cardiovascular diseases--report for meta-analysis of prospective studies open optimal cut-off points of body mass index in Chinese adults / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To verify the optimal cut-off points for overweight and obesity in Chinese adults based on the relationship of baseline body mass index (BMI) to all-cause mortality, and incidence of cardiovascular diseases from pooled data of Chinese cohorts.</p><p><b>METHODS</b>The prospective study data of existing cohort studies in China were collected, and the age-adjusted all-cause mortality stratified by BMI were estimated. The similar analysis was repeated after excluding deaths within the first three years of follow-up and after excluding smokers. The incidence of age-adjusted coronary heart disease (CHD) and stroke stratified by BMI were also analyzed. Multiple Cox regression coefficients of BMI for the incidence of CHD and stroke after controlling other risk factors were pooled utilizing the methods of weighting by inverse of variance to reveal whether BMI had independent effect and its strength on the incidence of CHD and stroke.</p><p><b>RESULTS</b>The data of 4 cohorts including 76,227 persons, with 745,346 person-years of follow-up were collected and analyzed. The age-adjusted all-cause mortality stratified by BMI showed a U-shaped curve, even after excluding deaths within the first three years of follow-up and excluding smokers. Age-adjusted all-cause mortality increased when BMI was lower than 18.5 and higher than 28. The incidence of CHD and stroke, especially ishemic stroke increased with increasing BMI, this was consistent with parallel increasing of risk factors. Cox regression analysis showed that BMI was an independent risk factor for both CHD and stroke. Each amount of 2 kg/m2 increase in baseline BMI might cause 15.4%, 6.1% and 18.8% increase in relative risk of CHD, total stroke and ischemic stroke. Reduction of BMI to under 24 might prevent the incidence of CHD by 11% and that of stroke by 15% for men, and 22% of both diseases for women.</p><p><b>CONCLUSION</b>BMI < or = 18.5, 24-27.9 and > or = 28 (kg/m2) is the appropriate cut-off points for underweight, overweight and obesity in Chinese adults.</p>