Serum lipids and their correlates in Chinese urban and rural populations of Beijing and Guangzhou. PRC-USA Cardiovascular and Cardiopulmonary Epidemiology Research Group

Exploring the Genetic Association between Obesity and Serum Lipid Levels Using Bivariate Methods

It is crucial to understand the genetic mechanisms and biological pathways underlying the relationship between obesity and serum lipid levels. Structural equation models (SEMs) were constructed to calculate heritability for body mass index (BMI), total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and the genetic connections between BMI and the four classes of lipids using 1197 pairs of twins from the Chinese National Twin Registry (CNTR). Bivariate genomewide association studies (GWAS) were performed to identify genetic variants associated with BMI and lipids using the records of 457 individuals, and the results were further validated in 289 individuals. The genetic background affecting BMI may differ by gender, and the heritability of males and females was 71% (95% CI [.66, .75]) and 39% (95% CI [.15, .71]) respectively. BMI was positively correlated with TC, TG and LDL-C in phenotypic and genetic correlation, while negatively correlated with HDL-C. There were gender differences in the correlation between BMI and lipids. Bivariate GWAS analysis and validation stage found 7 genes (LOC105378740, LINC02506, CSMD1, MELK, FAM81A, ERAL1 and MIR144) that were possibly related to BMI and lipid levels. The significant biological pathways were the regulation of cholesterol reverse transport and the regulation of high-density lipoprotein particle clearance (p < .001). BMI and blood lipid levels were affected by genetic factors, and they were genetically correlated. There might be gender differences in their genetic correlation. Bivariate GWAS analysis found MIR144 gene and its related biological pathways may influence obesity and lipid levels.

SYTL3-SLC22A3 Single-Nucleotide Polymorphisms and Gene-Gene/Environment Interactions on the Risk of Hyperlipidemia

The current study aims to further delineate the associations between the synaptotagmin-like 3 (SYTL3) and solute carrier family 22 member 3 (SLC22A3) single-nucleotide polymorphisms (SNPs) and their haplotypes and gene–gene (G × G)/environment (G × E) interactions on the risk of hyperlipidemia (HLP) in the Maonan and Han ethnic groups. Genotype distribution among the SYTL3–SLC22A3 SNPs in 2,829 individual patients bearing no relationship to each other (Han, 1,436; Maonan, 1,393) was analyzed utilizing next-generation sequencing techniques. The genotype frequencies of the rs6455600, rs2129209, and rs446809 SNPs were varied between the two ethnic groups (P < 0.05–0.001). Various SNPs were correlated with serum levels of triglyceride (TG; rs446809), total cholesterol (TC; rs6455600, rs2129209, and rs539298), and low-density lipoprotein cholesterol (LDL-C; rs446809) among the Han population, whereas various SNPs were also correlated with TC (rs6455600 and rs539298), TG (rs446809), and LDL-C (rs446809) levels in the Maonan ethnic group (P < 0.008–0.001). One part of haplotypes resulted in worsened HLP-related morbidity in the Han (SYTL3 A-C-A-A; SLC22A3 A-A and A-G; and SYTL3–SLC22A3 A-C-A-A-A-A and A-C-A-A-A-G) and Maonan (SYTL3 A-C-A-A; SLC22A3 A-A and A-G; and SYTL3–SLC22A3 A-C-A-A-A-A, G-T-C-A-A-A, and G-T-C-A-C-A) ethnic groups, whereas another part of haplotypes lowered HLP-related health risks in the Han (SLC22A3 C-A and C-G and SYTL3–SLC22A3 A-C-A-A-C-A, A-C-A-A-C-G, and G-T-C-A-C-A) and Maonan (SLC22A3 C-G and SYTL3–SLC22A3 A-C-A-A-C-G) ethnic groups. We discovered that the SYTL3–SLC22A3 SNPs and their haplotypes were associated with serum lipid levels and the risk of HLP in our studied populations.

Triglyceride to high-density lipoprotein cholesterol ratio and risk of atherosclerotic cardiovascular disease in a Chinese population

BACKGROUND AND AIMS

Triglyceride (TG) to high-density lipoprotein cholesterol (HDL-C) ratio may play a role in predicting cardiovascular events. We aimed to prospectively explore the association between the TG/HDL-C ratio and atherosclerotic cardiovascular disease (ASCVD), ischemic stroke, as well as coronary heart disease (CHD) in a Chinese population.

METHODS AND RESULTS

This prospective cohort study included 9368 participants from four Chinese populations in the People's Republic of China-United States of America (PRC-USA) Collaborative Study of Cardiovascular and Cardiopulmonary Epidemiology. Over a follow-up period of 20 years, 624 cases of ASCVD events including 458 ischemic stroke events and 166 CHD events were recorded. The relationship between the TG/HDL-C ratio and the endpoints was evaluated through multivariate Cox proportional hazard models adjusted for potential confounding variables, including age, sex, urban or rural residence, northern or southern China, occupational type, education, physical exercise, smoking status, drinking status, body mass index, hypertension, high low-density lipoprotein cholesterol, diabetes, and antihypertensive medication use at baseline. With the lowest TG/HDL-C tertile as the reference, the middle and highest tertiles had the hazard ratios (HRs) and 95% confidence intervals (CIs) of 1.13 (0.91, 1.40), 1.36 (1.10, 1.67) respectively for ASCVD (p for trend = 0.0028), and 1.19 (0.93, 1.54),1.47 (1.15, 1.87) respectively for ischemic stroke (p for trend = 0.0016). However, no significant association was found for CHD events.

CONCLUSION

TG/HDL-C ratio was positively associated with the risk of ASCVD and ischemic stroke events in the Chinese population.

Prevalence, awareness, treatment, and control of dyslipidemia among adults in Beijing, China

AIM

The present study aimed to determine the up-to-date prevalence, awareness, treatment, and control of dyslipidemia, and their distribution and related influencing factors in adults in Beijing, China.

METHOD

A cross-sectional study was conducted in 2008, using a four-stratified cluster sampling. Data from a questionnaire, physical examination, and blood sampling were obtained from 5761 adults aged 18-79 years.

RESULTS

The prevalence of high TC, high LDL-C, low HDL-C and TG was 12.2%, 17.9%, 12.0% and 15.1%, respectively. The prevalence of dyslipidemia was 35.4% (42.9% in men and 30.1% in women), and was similar in rural (35.3%) and urban (35.8%) areas. Dyslipidemia was associated with male gender, age, a family history of dyslipidemia, education at college or above, current smoker, overweight and obesity, intermediate and high waist circumference, hypertension and diabetes. Among all participants with dyslipidemia, 22.2% were aware of the diagnosis, 10.2% were receiving treatment, and 3.8% had dyslipidemia controlled. The proportion of those aware of their condition and those who were treated increased with age in both sexes. Of those aware of their dyslipidemia, 46.1% were on treatment, 51.0% had modified their lifestyle, and 24.5% were not receiving treatment or modifying their lifestyle.

CONCLUSIONS

The major type of dyslipidemia in Beijing is high LDL-C rather than high TG. The prevalence of dyslipidemia is similarly high in rural and urban areas, with low awareness, treatment and control. A comprehensive strategy toward the prevention, screening, treatment, and control of dyslipidemia is needed to slow the epidemic of cardiovascular disease.

Dyslipidemia in northeastern China

Dyslipidemia, is a major risk factor for premature coronary artery disease. Our aim was to estimate the prevalence of dyslipidemia (blood lipid abnormalities) and other risk factors associated with coronary artery diseases among an adult population in northeastern China. Throughout the months of September and October of 2007,a population-based cross-sectional study was conducted and a total of 3,815 individuals were included. Total cholesterol (TC), high-density cholesterol (HDL-C), low-density cholesterol (LDL-C), and triglycerides (TG) were measured. A binary logistic regression analysis was conducted to determine risk factors associated with dyslipidemia. The prevalence of hypercholesterolemia, high LDL-C, low HDL-C, and hypertriglyceridemia were 17.3%, 27.8%, 11.66% and 29.85%, respectively. The prevalence of hypertension, central obesity, alcoholic liver disease (ALD), non-ALD, diabetes and metabolic syndrome was higher in serum lipid abnormality groups than in the non-dyslipidemia group (p < 0.001). In a binary logistic regression, hyperlipidemia was positively correlated with age, male, hypertension, high body mass index, etc. There were negative correlations with being female and the level of education a subject had attained. Dyslipidemia is a major risk factor for premature coronary artery diseases and an important public health issue in the northeastern part of China. Dyslipidemia is more frequent than expected based on previous studies. To control dyslipidemia, routine evaluations in clinics and community centers are needed, as well as effective public health education.

Cigarette smoking status and smoking cessation counseling of Chinese physicians in Wuhan, Hubei province

Among the 347 physicians surveyed, 58% of the male physicians and 18.8% of the female physicians were current cigarette smokers; 54.4% of the male and 70.4% of the female physicians often or always provided smoking cessation counseling for patients; 37.5% of the physicians thought that for a Chinese smoker, cigarette smoking served as a social lubricant; 31.5% thought it a habit; 21.7% thought it a stress reliever; and 9.2% thought it a social status symbol. The following 5 variables were significantly associated with physicians' smoking cessation counseling frequency: their smoking status, perceived success in their past counseling, perceived influence, perceived exemplary role, and perceived responsibility. To increase physicians' smoking cessation counseling, the Chinese Ministry of Health would need to discourage physicians to smoke and appeal to their sense of responsibility to help patients quit smoking.

Distinct lipid/lipoprotein profiles and hormonal responsiveness in nine ethnic groups of postmenopausal Asian women: the Pan-Asia Menopause (PAM) study

BACKGROUND

Lipid/lipoprotein profiles, among other factors, are associated with risk of cardiovascular disease. Because cardiovascular disease varies in Asian countries, we hypothesized that lipid profiles differ in ethnic groups of postmenopausal Asian women. To add to the limited body of information currently available, we also investigated the effects of estrogen/progestin therapy on lipid/lipoprotein profiles in postmenopausal Asian women.

METHODS

The Pan-Asia Menopause (PAM) study was a prospective, randomized, double-blind clinical trial evaluating 1028 postmenopausal women at 22 investigational centers in 11 Asian countries/territories. Subjects were randomly assigned to one of three doses of continuous combined conjugated estrogens (CE)/medroxyprogesterone acetate (MPA): CE/MPA (in mg/day) = 0.625/2.5, 0.45/1.5 or 0.3/1.5. The treatment period, following baseline evaluations, consisted of six continuous 28-day cycles. Analysis of lipid profiles was a secondary objective of the PAM study. Total cholesterol, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), very low density cholesterol (VLDC-C), triglycerides and lipoprotein(a) were analyzed at a central laboratory by state-of-the-art methods.

RESULTS

Mean concentrations of total cholesterol, LDL-C, VLDL-C and triglycerides differed significantly among the nine ethnic groups of postmenopausal women. This difference was independent of body mass index and age, two factors that also influenced lipid/lipoprotein profiles. Mean HDL-C concentrations also differed, but this difference was influenced by body mass index in a weak interaction. All three doses of CE/MPA significantly lowered total cholesterol. Treatment with the high and middle doses significantly lowered LDL-C, and increased HDL-C, VLDL-C and triglycerides. The high dose produced a significant decrease in lipoprotein(a).

CONCLUSIONS

The different lipid/lipoprotein profiles in the nine ethnic groups of postmenopausal Asian women evaluated here suggest a relationship to differences in the prevalence of cardiovascular disease reported for different regions in Asia. However, the reported prevalence data on cardiovascular disease morbidity and mortality in the regions corresponding to the nine ethnic groups are insufficient to allow qualitative comparisons with the lipid profiles shown in our study. The lipid/lipoprotein changes in response to estrogen/progestin therapy observed here are consistent with those reported for Western women.

Prevalence and risk factors of overweight and obesity in China

OBJECTIVE

To examine the prevalence and risk factors of overweight and obesity in China.

RESEARCH METHODS AND PROCEDURES

A cross-sectional survey was conducted in a nationally representative sample of 15,540 Chinese adults in 2000-2001. Body weight, height, and waist circumference were measured by trained observers. Overweight and obesity were defined according to the World Health Organization classification. Central obesity was defined according to guidelines of the International Diabetes Federation.

RESULTS

Mean BMI and waist circumference were 23.1 kg/m2 and 79.6 cm, respectively, for men and 23.5 kg/m2 and 77.2 cm, respectively, for women. The prevalences of overweight and obesity were 24.1% and 2.8% in men and 26.1% and 5.0% in women, respectively. The prevalence of central obesity was 16.1% in men and 37.6% in women. The prevalences of overweight, obesity, and central obesity were higher among residents in northern China compared with their counterparts in southern China and among those in urban areas compared with those in rural areas. Lifestyle factors were the most important risk factors to explain the differences in overweight and central obesity between northern and southern residents. Among women, lifestyle and diet were the most important risk factors to explain the differences between urban and rural residents, whereas socioeconomic status, lifestyle, and diet were all important among men.

DISCUSSION

Our study indicates that overweight and obesity have become important public health problems in China. Environmental risk factors may be the main reason for regional differences in the prevalence of overweight and obesity in China.

Plasma lipid, lipoprotein and apolipoprotein levels in a random population sample of 2875 Hong Kong Chinese adults and their implications (NCEP ATP-III, 2001 guidelines) on cardiovascular risk assessment

The age- and sex-related levels of plasma lipids, lipoproteins and apolipoproteins in a random population sample of 2875 Hong Kong Chinese Adults (1397 men and 1478 women aged 25-74) and their implications on cardiovascular risk assessment are reported. Total cholesterol, low-density lipoprotein (LDL)-cholesterol and triglycerides increased with age in both sexes. Postmenopausal women had the worst profiles. They also showed higher triglyceride and non-high density lipoprotein (non-HDL)-cholesterol and had higher percentage of values greater than the desirable limits, compared with men of the same age groups. Overall 39% of men and 29% of women had non-HDL cholesterol of 4.2 mmol/L or greater. Apolipoproteins A-I and B followed the same trends as HDL-cholesterol and LDL-cholesterol, respectively. Apolipoprotein E (apo E) allele frequencies were: epsilon2 8.7, epsilon3 80.4 and epsilon4 10.9% with the genotype having a significant effect on plasma apo E concentration (p < 0.001). Carriers of the epsilon2 allele had higher apo E values than those homozygous for E3. Lipoprotein(a) levels were higher in women than men (geometric mean 152 versus 102 mg/L, p < 0.05) and in women with FSH above versus below 40 IU/L (185 versus 136 mg/L, p < 0.05). With respect to the NCEP ATP-III 2001 guidelines, the prevalence of hyperlipidemia in the Hong Kong population approached those in high CHD prevalence Caucasian communities. Local management guidelines and community-wide programs to reduce fat intake, increase regular moderate exercise and reduce the prevalence of overweight and obesity are urgently required, and hormone replacement therapy for postmenopausal women might be warranted.

Serum triglycerides as a risk factor for cardiovascular diseases in the Asia-Pacific region

BACKGROUND

The importance of serum triglyceride levels as a risk factor for cardiovascular diseases is uncertain.

METHODS AND RESULTS

We performed an individual participant data meta-analysis of prospective studies conducted in the Asia-Pacific region. Cox models were applied to the combined data from 26 studies to estimate the overall and region-, sex-, and age-specific hazard ratios for major cardiovascular diseases by fifths of triglyceride values. During 796,671 person-years of follow-up among 96,224 individuals, 670 and 667 deaths as a result of coronary heart disease (CHD) and stroke, respectively, were recorded. After adjustment for major cardiovascular risk factors, participants grouped in the highest fifth of triglyceride levels had a 70% (95% CI, 47 to 96) greater risk of CHD death, an 80% (95% CI, 49 to 119) higher risk of fatal or nonfatal CHD, and a 50% (95% CI, 29% to 76%) increased risk of fatal or nonfatal stroke compared with those belonging to the lowest fifth. The association between triglycerides and CHD death was similar across subgroups defined by ethnicity, age, and sex.

CONCLUSIONS

Serum triglycerides are an important and independent predictor of CHD and stroke risk in the Asia-Pacific region. These results may have clinical implications for cardiovascular risk prediction and the use of lipid-lowering therapy.

Serum Total and Lipoprotein Cholesterol Levels and Awareness, Treatment, and Control of Hypercholesterolemia in China

BACKGROUND

Cardiovascular disease has become the leading cause of death in China. We examined the levels of serum total and lipoprotein cholesterol and status of awareness, treatment, and control of hypercholesterolemia in China.

METHODS AND RESULTS

A cross-sectional survey in a nationally representative sample of 15,540 Chinese adults 35 to 74 years of age was conducted during 2000 to 2001. Serum cholesterol was measured by use of standard methods, and information on treatment of hyperlipidemia was obtained by use of a standard questionnaire. Age-standardized mean levels of total, HDL, and LDL cholesterol and triglycerides were 186.1, 51.7, 109.5, and 128.1 mg/dL, respectively. Of the Chinese population 35 to 74 years of age, 23.8% (112,500000 persons) had borderline high total cholesterol (200 to 239 mg/dL), and 9.0% (42,540000 persons) had high total cholesterol (> or =240 mg/dL). The population estimates for borderline high (130 to 159 mg/dL), high (160 to 189 mg/dL), and very high (> or =190 mg/dL) LDL cholesterol were 17.0% (80,122000 persons), 5.1% (24,329000 persons), and 2.7% (12,822000 persons), respectively. In addition, 19.2%, or 90 803 000 persons, had a low HDL cholesterol (<40 mg/dL). Among those who had a total cholesterol > or =200 mg/dL or who were on cholesterol-lowering medications, the proportion of men and women who were aware, treated, and controlled was only 8.8% and 7.5%, 3.5% and 3.4%, and 1.9% and 1.5%, respectively.

CONCLUSIONS

The prevalence of hypercholesterolemia was relatively high and the percentage of adults with controlled blood cholesterol was low in China. Prevention and treatment of hypercholesterolemia should be an important component of a national strategy to reduce the substantial and increasing burden of cardiovascular disease in China.

Differences in cardiovascular disease risk factors between Japanese in Japan and Japanese-Americans in Hawaii: the INTERLIPID study

Despite increase in serum total cholesterol, high smoking rate, and frequency of adverse blood pressure levels in Japan, coronary heart disease (CHD) incidence and mortality apparently remain substantially lower at all ages in Japan than in the US and other Western societies. To better understand these differences, we compared CHD biomedical risk factors and dietary variables in Japanese living in Japan and 3rd and 4th generation Japanese emigrants living a primarily Western lifestyle in Hawaii, in an ancillary study of the INTERMAP. Men and women aged 40-59 years were examined by common standardized methods-four samples in Japan (574 men, 571 women) and a Japanese-American sample in Hawaii (136 men, 131 women). Average systolic (SBP) and diastolic (DBP) blood pressures were significantly higher in men in Japan than in Hawaii; there were no significant differences in women. The treatment rate of hypertension was much lower in Japan than Hawaii. Smoking prevalence was higher, markedly so for men, in Japan than Hawaii. Body mass index, serum total and low-density lipoprotein cholesterol, HbA1c, and fibrinogen were significantly lower in Japan than in Hawaii; high-density lipoprotein cholesterol was higher in Japan. Total fat, saturated fatty acid intake, and Keys dietary lipid score were lower in Japan than in Hawaii. Polyunsaturated/saturated fatty acid ratio and omega-3 fatty acid intake were higher in Japan than in Hawaii. In conclusion, levels of several, especially lipid, CHD risk factors were generally lower in Japanese in Japan than in Japanese in Hawaii. These differences were smaller for women than men between Japan and Hawaii. They may partly explain lower CHD incidence and mortality in Japan than Western industrialized countries.

Lipids and coronary heart disease in Asia

In Western countries, it has been shown that coronary heart disease (CHD) is related to high serum total cholesterol (TC) levels. In less developed continents such as Asia and Africa, serum lipid levels are low and CHD incidence is much lower as compared with Western countries. With growing urbanization and industrialization in Asia, it has been shown that there is a concomitant rise in the level of serum TC and with it a rise in CHD. In all the Asian countries, serum TC levels are also higher in the urban compared with the rural population. Singapore, the only Asian country which is 100% urbanized since 1980, showed a rise of serum TC similar to that seen in the US and UK from the 1950s to the 1980s followed thereafter by a fall. This is reflected in the trend (rise followed by a fall) of CHD morbidity and mortality as well. In spite of a declining trend in serum TC level, CHD morbidity and mortality are still high in Singapore and comparable to the Western countries. The rest of the Asian countries show a different pattern from Singapore. In general, there is still a rising trend in serum TC level and in CHD mortality in most Asian countries. However, Japan is considered an exception in having a decreasing CHD mortality in spite of an increasing trend in serum TC. This may be attributed to a better control of other CHD risk factors such as hypertension and smoking. The rising trend in serum TC level remains a cause for concern, as this will emerge as a major problem for CHD morbidity and mortality in the future.

Prevalence and correlates of alcohol use: a population-based study in Hong Kong

OBJECTIVE

To estimate the prevalence and pattern of alcohol use and to analyse the socio-demographic and biological correlates of alcohol drinking in Hong Kong Chinese.

DESIGN

A population-based cross-sectional study conducted from December 1994 to October 1996.

SETTING AND PARTICIPANTS

2900 randomly selected subjects age 25-74 years who participated in the Cardiovascular Risk Factor Prevalence Study in Hong Kong.

RESULTS

Alcohol consumers comprised 55.4% (95% CI: 52.8-58.0) of men and 19.4% (95% CI: 17.4-21.4) of women. The median weekly ethanol consumed by male and female drinkers were 9.6 g and 3.6 g, respectively. Beer was the main source of alcohol; 61.5% of drinkers consumed beer as their main drink. In stepwise multiple regression among drinkers, male sex, smoking, high density lipoprotein cholesterol, primary or below education, diastolic blood pressure and separated or widowed marital status were associated positively with weekly ethanol consumption.

CONCLUSION

In this representative sample of Hong Kong adults, the majority were either non-drinkers or very light drinkers, which can be used as a benchmark to measure changes in drinking pattern in the future. The putative protective effect of alcohol on heart disease could be due to the higher level of HDL in moderate drinkers.

Ethnic variation and in vivo effects of the -93t-->g promoter variant in the lipoprotein lipase gene

Recently, a (t-->g) transition at nucleotide -93 in the lipoprotein lipase (LPL) gene promoter has been observed in Caucasians. Here, we have compared the frequency of the -93g carriers in three distinct populations (Caucasians, South African Blacks, and Chinese). The carrier frequency in the Caucasian population was 1.7% (4/232), which was in contrast to the South African Black population, which had a frequency for this allele of 76.4% (123/161) of the individuals tested. This transition was not observed in the Chinese population under study. Near complete linkage disequilibrium between the -93g and the previously described D9N mutation was observed in the Caucasian population but not in South African Blacks. To further assess the ancestral origins of these DNA changes, DNA haplotyping using a CA repeat 5' to these substitutions was performed. The -93t allele was associated with only a few specific dinucleotide repeat sizes. In contrast, the -93g allele occurred on chromosomes with many different repeat lengths. The broad distribution of repeats on -93g carrying chromosomes, their high frequency in the South African Black population, and the conservation of the -93g allele among different species may suggest that the -93g allele is the ancestral allele on which a transition to t and the D9N mutations arose. The very high frequency of the -93g allele distinct from the N9 allele in a cohort of Black South Africans allowed us to specifically assess the phenotypic effects of the -93g allele on lipids. Individuals homozygous for the g allele at -93 showed mildly decreased triglycerides compared with individuals homozygous for the t allele (1.14 +/- 0.66 mmol/L versus 0.82 +/- 0.3; P = .04). Thus, the -93g allele in this cohort is associated with low plasma triglyceride levels.

Distribution and correlates of lipids and lipoproteins in elderly Japanese-American men. The Honolulu Heart Program

Adverse lipid and lipoprotein levels are clearly linked with increased risk of cardiovascular disease in middle age, but evidence in elderly and minority populations is less certain. In this study the distribution and correlates of lipids and lipoproteins were evaluated cross-sectionally in 3044 elderly (71 to 93 years) Japanese-American men from the Honolulu Heart Program who were recently reexamined (1991 to 1993). Mean +/- SD lipid concentrations were 189 +/- 33 mg/dL for total cholesterol, 51 +/- 13 mg/dL for HDL cholesterol, 109 +/- 31 mg/dL for LDL cholesterol, and 147 +/- 89 mg/dL for triglycerides. Prevalence of dyslipidemic patterns was relatively infrequent (total cholesterol > or = 240 mg/dL: 6.7%; HDL cholesterol < 35 mg/dL, 6.4%; LDL cholesterol > or = 160 mg/dL: 5.5%; triglycerides > or = 200 mg/dL. 18.7%), while prevalence of desirable total (< 200 mg/dL) and HDL cholesterol (> or = 60 mg/dL) concentrations was more common (62.7% and 23.7%, respectively). Mean levels of total cholesterol, LDL cholesterol, and triglyceride decreased significantly with increasing age (P < .001), while mean HDL cholesterol level increased slightly (P < .05). After univariate analyses of potential correlates, multiple linear regression models were used to identify variables independently associated with each of the lipids. After adjustment for other variables, levels of fibrinogen and hematocrit were positively associated and insulin, white blood cell count, and use of diabetic medication were negatively associated with total cholesterol. Correlates for LDL cholesterol were similar but also included vital capacity (positive relation) and alcohol (negative relation). Heart rate, physical activity, alcohol, and hematocrit were positively associated with HDL cholesterol; body mass index, subscapular skinfold thickness, glucose, fibrinogen, white blood cell count, and hypertension were negatively associated. Factors associated with triglycerides tended to be similar, yet the direction of relations was reversed. Age-adjusted total cholesterol levels were significantly lower in men who had coronary surgery, thromboembolic stroke, and hemorrhagic stroke but were higher in those with peripheral vascular disease. Lower HDL cholesterol levels were found in men with prevalent angina, angioplasty, definite myocardial infarction, thromboembolic stroke, and peripheral vascular disease. LDL cholesterol and triglycerides showed fewer significant relations with these conditions. Findings indicate that elderly Japanese-American men have a favorable lipid profile, except for elevated triglyceride levels, relative to levels in other populations of older Americans and that a number of cardiovascular risk factors and diseases are strongly associated with lipids in elderly men. These analyses also identify several modifiable factors that may favorably influence lipid and lipoprotein levels in the elderly.

Plasma lipid profiles and epidemiology of atherosclerotic diseases in Taiwan--a unique experience

Rapid economic growth in Taiwan is accompanied by changing lifestyles, and the mortality pattern has switched from predominantly infectious diseases to chronic diseases. Age-adjusted mortality from heart disease has increased slowly but steadily. However, mortality from heart disease in Taiwan remains low compared with many other countries. Mortality from the cerebrovascular diseases has decreased gradually. Current age- and sex-specific values of blood cholesterol low density lipoprotein cholesterol (LDL-C) and triglyceride (TG) are, in general, higher than values in mainland China, but lower than those in the NHANES III and PROCAM studies. From 1950 to 1987, percent dietary fat increased from 16% to 36% in Taiwan. However, a high polyunsaturated fat/saturated fat (P/S) ratio (1.3) maintained during this period may in part explain the favorable blood lipid status and low mortality from heart disease. Data from prospective studies are scarce. In case-control studies carried out in Chinese, significantly higher values of TG, CHOL LDL-C, but lower high density lipoprotein cholesterol (HDL-C) levels have often been found in coronary artery disease (CAD) patients than in controls. The percent differences in TG and HDL-C values (20%) were much greater than those of CHOL and LDL-C (3%). A few studies have identified the TG level as an independent risk factor for stroke and CAD in Taiwan, where a moderate to high fat diet with an advantageous P/S ratio is consumed.

Frequency of consumption of selected indicator foods and serum cholesterol. GISSI-EFRIM investigators. Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto--Epidemiologia dei Fattori di Rischio dell'Infarto Miocardico

The relationship between frequency of consumption of eleven indicator foods (milk, meat, liver, carrots, green vegetables, fruit, eggs, ham, fish, cheese and alcohol) and serum cholesterol was investigated in the comparison group of a case-control study of acute myocardial infarction conducted in Italy. Data were collected on 792 subjects from various Italian regions, admitted to hospital for acute conditions unrelated to any known or potential risk factor for myocardial infarction or to long-term modifications in diet. No statistically or epidemiologically meaningful relationship emerged between serum cholesterol level and frequency of consumption of any of these foods. Cholesterol levels rose according to increasing consumption tertiles for most of the indicator foods considered. Higher values for the higher tertile of consumption were observed for meat, ham and eggs, but also for fruit, carrots and green vegetables. However, correlation coefficients between frequency of consumption of various food items and serum cholesterol level were uniformly low for all food items considered, ranging between -0.09 (for milk) and 0.19 (for ham). Although a more comprehensive diet history may lead to different indications, the present data are not suggestive of any major influence of long-term frequency of consumption of a few selected indicator foods on serum cholesterol levels.

A population-based epidemiological study on cardiovascular risk factors in Kin-Chen, Kinmen

We conducted a population survey of cardiovascular risk factors in Kin-Chen, Kinmen (Quemoy), an island under military control for 40 years and the focal point of confrontation between mainland China and Taiwan. During the period 1992-1994, all residents > or = 30 years of age in Kin-Chen, the largest township in Kinmen, were invited to participate. The response rate was 60.3% (3826/6346). The prevalence of hypertension (> or = 160/95 mmHg and/or under treatment) was 25.2% in men and 17.6% in women. The rate for smoking was 41.5% in men and 2.9% in women. The prevalence of diabetes was 6.7% in men and 6.4% in women. Mean values for systolic blood pressure, diastolic blood pressure, total cholesterol, triglyceride, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol were 135.3 mmHg, 85.5 mmHg, 5.3 mmol/l, 1.1 mmol/l, 3.5 mmol/l and 1.4 mmol/l in men; and 128.0 mmHg, 79.5 mmHg, 5.2 mmol/l, 1.0 mmol/l, 3.3 mmol/l and 1.5 mmol/l in women, respectively. The unexpectedly high prevalence of hypertension in Kin-Chen male may reflect the effect of more than 40 years of military control and discipline. The high serum cholesterol level in Kin-Chen relative to mainland China and the low triglyceride level relative to Taiwan and Beijing, suggest further study of the contributions of diet and other psychosocial or environmental factors.

Prevalence of coronary heart disease and cardiovascular risk factors in middle aged males in a defined population in central Sri Lanka

In a cross-sectional survey, we estimated the prevalence of coronary heart disease in a sample of 975 middle-aged males (35-59 years), from a defined population in the Central province of Sri Lanka using the London School of Hygiene cardiovascular questionnaire and a 12-lead electrocardiogram. The estimated prevalence rates were: (a) Definitive evidence of ischemic heart disease (positive symptoms and ECG changes of ischemia), 16/1000 (95% C.L., 9-27). (b) Evidence of coronary heart disease based on history alone 54/1000 (95% C.L., 40-71). (c) Estimate based on ECG changes of ischemia without symptoms 32/1000 (95% C.L., 21-46). Median values for major risk factors were: systolic blood pressure 120 mmHg, diastolic blood pressure 88 mmHg, serum cholesterol 4.99 mmol/l, high density lipoproteins 0.99 mmol/l and body-mass index 20.4 kg/m2. About half (57.9%) the subjects were current smokers, 17% had actual hypertension (systolic blood pressure > 159 mmHg and/or diastolic blood pressure > 94 mmHg and/or been treated for hypertension), 12.6% had hypercholesterolemia (serum cholesterol levels > 6.5 mmol/l), 18.4% had a body-mass index > 24 kg/m2 and 5.8% were diabetic. Hypercholesterolemia (> 6.5 mmol/l), a higher body-mass index (> 24 kg/m2) and diabetes were more prevalent among subjects living in an urban rather than a rural environment.

Stroke incidence and mortality in rural and urban Shanghai from 1984 through 1991. Findings from a community-based registry

BACKGROUND

Mortality from stroke has declined in many countries. This decline may result from a fall in incidence of stroke or a decrease in case fatality from stroke. The present study was conducted to investigate the temporal trends of incidence rate, mortality rate, and case fatality of stroke in an urban and rural Chinese population.

METHODS

A community-based registry study was established in 1983 in defined rural and urban areas of Shanghai with a population aged 35 to 74 years of approximately 86,000 subjects, adhering to the methods and definitions of the World Health Organization MONICA protocol. All stroke events occurring in the population aged 35 to 74 years in these areas were registered by a special three-level case-registration system.

RESULTS

From 1984 through 1991, 1391 stroke cases were identified. No significant change in the incidence rate of stroke was observed from 1984 through 1991 in men and women living in rural and urban areas. Age-standardized mortality rates (per 100,000 person years) of stroke declined significantly during this period, except for rural women. The annual changes and 95% confidence intervals of age-standardized mortality rates were: for rural men -4.6% (-5.4, -3.9), for rural women -0.6% (-1.6, 0.5), for urban men -2.5% (-3.5, -1.6), and for urban women -4.7% (-5.2, -4.2). A significant decrease in case fatality from stroke from 1984 through 1991 was found among men living in rural areas (from 62.4% to 46.0%) and among women living in urban areas (from 48.4% to 33.3%). Overall case fatality, however, showed a nonsignificant decline over time.

CONCLUSIONS

We observed a decline in stroke mortality rate in a rural and urban Chinese population. No significant changes in stroke incidence were found in this study, whereas case fatality appeared to have decreased, in particular among men living in rural areas and women living in urban areas.

Body mass, fat distribution and cardiovascular risk factors in a lean population of south China

The associations of body mass index and abdominal adiposity, represented by an elevated waist/hip circumference ratio, with cardiovascular risk factors were examined in men and women, aged 28-69 years, from urban and rural areas of Guangzhou, China. Mean body mass index ranged from 20.1 to 21.9 kg/m2 across the four sex- and area-groups. Mean waist/hip ratio was 0.84 in men and 0.80 in women. After accounting for age and body mass index, waist/hip ratio was associated negatively (p < 0.05) with fasting serum HDL cholesterol (both sexes), and positively with serum triglycerides (both sexes), total and LDL cholesterol (men only), uric acid (both sexes), glucose (women only), and mean systolic blood pressure (women only). Body mass index was associated in a similar direction with most of these risk factors. These data confirm that abdominal adiposity is independently associated with cardiovascular disease risk factors, even in a lean Asian population.

Familial hypercholesterolemia in China. Identification of mutations in the LDL-receptor gene that result in a receptor-negative phenotype

Familial hypercholesterolemia (FH), caused by many different mutations in the low-density lipoprotein (LDL)-receptor gene, invariably leads to severe premature coronary heart disease (CHD) in homozygous individuals. Heterozygous FH patients are less severely affected but are still at increased risk of CHD in most populations. Although FH homozygotes in China are affected similarly to those elsewhere, heterozygotes are not detected in the general population and obligate heterozygotes are often not hypercholesterolemic by Western standards. Mutations in the LDL-receptor genes of 10 homozygous FH patients from the Jiang-su province of China and their heterozygous parents were analyzed. These include one large and two minor deletions and eight point mutations: four are predicted to introduce a premature stop codon, five to result in a single amino acid substitution or deletion, and one to produce a protein with an abnormal cytoplasmic tail. Expression of the mutant LDL-receptor cDNAs in vitro confirmed that these mutations impaired LDL-receptor function and that several would cause a receptor-negative phenotype. Thus, the lack of clinical expression in obligate FH heterozygotes is not due to unusually "mild" mutations in the LDL-receptor gene, and other genetic or environmental factors must therefore be important in determining phenotypic expression.

Plasma lipoprotein and apolipoprotein levels in Taipei and Framingham

We compared the plasma lipoprotein cholesterol, triglyceride, apolipoprotein (apo) A-I, apoB, and lipoprotein(a) [Lp(a)] concentrations in a low coronary heart disease (CHD) risk population (n = 440) in Taipei with a high CHD risk population (n = 428) in Framingham matched for age, sex, and menopausal status. Taipei men had significantly lower low-density lipoprotein cholesterol (LDL-C) (-20 mg/dL, -14%, P < .01) and apoB (-7 mg/dL, -6%, P < .05) levels and significantly higher high-density lipoprotein cholesterol (HDL-C) levels (6 mg/dL, 13%, P < .01) than Framingham men. Taipei women had significantly lower LDL-C (-18 mg/dL, -15%, P < .01) and higher HDL-C (4 mg/dL, 7%, P < .01) levels than Framingham women. Median concentrations and distributions of Lp(a) by sex were similar in Taipei and Framingham. After adjusting for body mass index and smoking status, only differences in total cholesterol and LDL-C levels remained significantly different for both sexes between the two populations (P < .01). Gender differences for lipids within populations were similar. After adjusting for age, body mass index, and smoking status, women in both Taipei and Framingham had significantly lower mean triglyceride, LDL-C, and apoB levels and significantly higher HDL-C and apoA-I levels than men. Postmenopausal women in Taipei had significantly higher mean total cholesterol, LDL-C, HDL-C, apoA-I, apoB, and Lp(a) levels than premenopausal women (P < .05), whereas in Framingham postmenopausal women had significantly higher total cholesterol, triglyceride, LDL-C, and apoB levels than premenopausal women (P < .05). Our data are consistent with the concept that plasma lipoprotein cholesterol levels (especially LDL-C) but not apolipoprotein values explain some of the twofold difference in age-adjusted CHD mortality between these two populations.