Cardiovascular diseases in Chinese, Malays, and Indians in Singapore. II. Differences in risk factor levels.

STUDY OBJECTIVE--The aim of the study was to examine cardiovascular risk factors to see how these might explain differences in cardiovascular disease mortality among Chinese, Malays, and Indians in the Republic of Singapore. DESIGN--The study was a population based cross sectional survey. Stratified systematic sampling of census districts, reticulated units, and houses was used. The proportions of Malay and Indian households were increased to improve statistical efficiency, since about 75% of the population is Chinese. SETTING--Subjects were recruited from all parts of the Republic of Singapore. SUBJECTS--2143 subjects aged 18 to 69 years were recruited (representing 60.3% of persons approached). There were no differences in response rate between the sexes and ethnic groups. MEASUREMENTS AND MAIN RESULTS--Data on cardiovascular risk factors were collected by questionnaire. Measurements were made of blood pressure, serum cholesterol, low and high density lipoprotein cholesterol, fasting triglycerides and plasma glucose. In males the age adjusted cigarette smoking rate was higher in Malays (53.3%) than in Chinese (37.4%) or Indians (44.5%). In both sexes, Malays had higher age adjusted mean systolic blood pressure: males 124.6 mm Hg v 121.2 mm Hg (Chinese) and 121.2 mm Hg (Indians); females 122.8 mm Hg v 117.3 mm Hg (Chinese) and 118.4 mm Hg (Indians). Serum cholesterol, low density lipoprotein cholesterol and triglyceride showed no ethnic differences. Mean high density lipoprotein cholesterol in males (age adjusted) was lower in Indians (0.69 mmol/litre) than in Chinese (0.87 mmol/litre) and Malays (0.82 mmol/litre); in females the mean value of 0.95 mmol/litre in Indians was lower than in Chinese (1.05 mmol/litre) and Malays (1.03 mmol/litre). Rank prevalence of diabetes for males was Indians (highest), Malays and then Chinese; for females it was Malays, Indians, Chinese. CONCLUSIONS--The higher mortality from ischaemic heart disease found in Indians in Singapore cannot be explained by the major risk factors of cigarette smoking, blood pressure and serum cholesterol; lower high density lipoprotein cholesterol and higher rates of diabetes may be part of the explanation. The higher systolic blood pressures in Malays may explain their higher hypertensive disease mortality.     

Smoking,blood pressure and serum cholesterol-effects on 20-year mortality

BACKGROUND: To study the impact of smoking and blood pressure conditional on serum total cholesterol levels, we investigated the 20-year mortality risk associated with high systolic blood pressure (> or =140 mmHg) and smoking, at low (<5.2 mmol/Liter), medium (5.2-6.49mmol/Liter), and high (> or =6.5 mmol/Liter) serum total cholesterol levels. METHODS: The study population comprised a cohort of 50,000 men and women age 30-54 years, examined between 1974 and 1980, in five Dutch towns. The duration of follow-up averaged 20 years. Age-adjusted relative risks (RRs) for mortality from coronary heart disease (CHD), cardiovascular diseases (CVD) and all causes were estimated, for six risk profiles (based on levels of total cholesterol, systolic blood pressure and smoking), using Cox proportional hazards analysis. RESULTS: Given a low cholesterol level, smoking had a larger impact than elevated blood pressure on CHD, CVD and all-cause mortality. The combination of elevated blood pressure and smoking among persons with low cholesterol was associated with RRs of 3.0 for CHD, 6.0 for CVD and 4.1 for all-cause mortality in men, and 2.3, 3.6 and 2.6, respectively, in women. Among persons with high cholesterol, the combination of high blood pressure and smoking was associated with RRs of 9.7 for CHD, 13.9 for CVD and 5.7 for all-cause mortality in men, and 15.9, 9.3 and 4.3, respectively, in women. For each risk profile, the absolute number of CHD, CVD and total deaths was larger in men than in women. CONCLUSIONS: The results demonstrate the potential power of a multifactorial approach to risk factor reduction in the prevention of cardiovascular diseases and all-cause mortality.     

Incidence of hypertension and non-insulin dependent diabetes mellitus and associated risk factors in a rapidly developing Caribbean community: the St James survey, Trinidad.

OBJECTIVE: To compare the incidence rates of hypertension and non-insulin dependent diabetes mellitus in relation to ethnicity and other characteristics in a rapidly developing community. DESIGN: Prospective surveillance of a total community for five years. SUBJECTS: Cohort of 2491 men and women aged 35 to 69 years (79% response), of African, Indian and "other' (mainly Afro-European) descent. RESULTS: During surveillance, secular increases occurred in fasting blood glucose concentrations in both sexes and in body mass index (BMI) in men, with apparent secular reductions in systolic blood pressure in both sexes. Incidence rates of hypertension did not differ significantly with ethnicity, ranging between 33 and 41 per 1000 person-years in men and between 27 and 32 per 1000 person-years in women. In men, the incidence of diabetes (per 1000 person-years) in Indians (24) was significantly higher than in Africans (13) and others (11). In women, the diabetic incidence was similar to that for men in Indians (23) and Africans (14), but in others was twice that in men (21). In both sexes, weight gain was an important risk factor for hypertension, whereas risk of diabetes increased with BMI at baseline. The increased risk of diabetes in Indians among men was independent of baseline BMI and blood glucose. CONCLUSION: Apart from the increased risk of diabetes in Indians, ethnicity had no significant influence on incidence rates of hypertension and diabetes in Trinidad. Secular increases in blood glucose in both sexes and in BMI in men probably contributed to the concurrent increase in mortality from coronary heart disease in this community.     

Factors associated with paradoxical survival at higher blood pressures in the very old.

Paradoxically greater survival for persons aged 85 years and older with higher blood pressures has been reported in a Finnish population study (Br Med J 1988;296:887-9). In a previous report, the authors demonstrated improved 10-year survival with increasing diastolic blood pressure in men (but not in women) aged 75 years and older in the Rancho Bernardo Chronic Disease Study (Br Med J 1989;298:1356-7). However, few of the covariates which could potentially explain this effect were obtained at the visit used in that analysis. In an effort to confirm these reports of paradoxical survival and to explore possible reasons for them, the authors analyzed all-cause and cardiovascular mortality in 795 men and women aged 75-96 years (mean, 80.6), evaluated in 1984-1987 and followed prospectively for an average of 3 years after that comprehensive examination. Of 63 deaths, 48 (76%) were in men; 43 (68%) of all deaths were cardiovascular. Kaplan-Meier survival analyses showed a significant trend for improved survival with increasing diastolic pressure in men aged 80 years and older versus all-cause mortality (chi 2 p less than or equal to 0.01), and cardiovascular mortality (chi 2 p less than or equal to 0.00). These trends were not evident in men aged less than 80 years or in women in either age group. Results were not explained by differences in the use of antihypertensive medication, pulse pressure, history of hypertension, history of coronary heart disease, isolated systolic hypertension, interval change in diastolic pressure (over an average of 12 years), or by cholesterol, triglycerides, fasting plasma glucose, smoking, or body mass index. Thus, the paradoxical relation of improved all-cause and cardiovascular survival in men aged 80 years or older with higher diastolic pressure is not explained by a wide range of biologic and historical factors.     

Effects of isolated post-challenge hyperglycemia on mortality in American Indians: the Strong Heart Study

PURPOSE: To assess the effects of isolated post-challenge hyperglycemia (IPH) on risk of cardiovascular disease (CVD), cancer, and all-cause mortality in American Indians using longitudinal data from the Strong Heart Study. METHODS: Of 4549 American Indian women and men aged 45 to 74 years participating in the Strong Heart Study, 4304 had fasting blood measurements or oral glucose tolerance test (OGTT) data to ascertain diabetes status. At baseline and follow-up, a personal interview was conducted, and physical examinations and laboratory tests were performed. Fasting blood samples were drawn for measurement of glucose, fibrinogen, insulin, lipids, lipoproteins, creatinine, and hemoglobin A1c (HbA1c). A 75-g OGTT was performed. Five diabetes categories were defined: (i) known diabetes, (ii) newly diagnosed diabetes (fasting glucose > or =126 mg/dL and no history of diabetes or diabetes medication; ADA-new diabetes), (iii) IPH, (iv) impaired fasting glucose (> or =110 - <126 mg/dL; IFG), and (v) normal fasting glucose (<110 mg/dL; NFG). Surveillance was initiated to determine CVD, cancer, and all-cause mortality over 9 years. RESULTS: IPH had a worse CVD risk factor profile than NFG, but IPH was associated with a better CVD risk factor profile than known diabetes or ADA-new diabetes. At follow-up, individuals with IFG had no increased risk for CVD or all-cause mortality, whereas those with ADA-new or known diabetes had significantly increased risk (RR = 1.70 and 1.40 for ADA-new diabetes, and RR = 2.87 and 2.19 for known diabetes, respectively). Those with IPH had nonsignificant elevations in risk for CVD (RR = 1.54) and all-cause (RR = 1.27) mortality. Cancer mortality was not increased in those with IFG, IPH, ADA-new diabetes, or known diabetes compared to those with NFG. CONCLUSIONS: Among American Indians 45 to 74 years of age, IPH is associated with nonsignificant elevations in total and CVD mortality. The magnitude of mortality risk associated with IPH is intermediate between diabetes and IFG. Because those with IPH are at high risk for diabetes, American Indians with IPH should be targeted for diabetes prevention.     

Forty-Year Mortality From Cardiovascular Diseases and All Causes of Death in the US Railroad Cohort of the Seven Countries Study

Forty-year mortality and its association with entry risk factor levels is reported in men employed in the US Railroad industry within the Seven Countries Study of Cardiovascular Diseases. Cardiovascular risk factors were measured in 2571 men aged 40-59 at entry examination in 1957-1959 and after 5 years. Mortality data were collected during 40 years of follow-up (overall mortality of 83.4%). The main causes of death were coronary heart disease (CHD, 32.9% of all causes using strict criteria), atherosclerotic cardiovascular diseases (including coronary, stroke and peripheral artery diseases, (ACVD), 53.2% of all causes) and cancer (25.1% of all causes). Multivariate analysis showed that age, systolic blood pressure, serum cholesterol and cigarette consumption were strongly and significantly associated with all-cause mortality, coronary mortality and cardiovascular mortality. Multivariate relative risks per 5 years of age were 1.31 for all-causes, 1.32 for CHD and 1.36 for ACVD; per 20 mmHg systolic blood pressure were 1.12, 1.23 and 1.26, respectively; per 1 mmol/l of serum cholesterol were 1.06, 1.18 and 1.14, respectively; and per 10 cigarettes smoked per day were 1.14, 1.12 and 1.13, respectively. During a 40-year period classical cardiovascular risk factors were highly predictive of coronary, cardiovascular and all-cause mortality in a US working population.     

The predictive role of blood glucose for mortality in subjects with cardiovascular disease

Using the Framingham Heart Study data (United States, 1948-1978), the authors examined the association of blood glucose with 2-year all-cause, cardiovascular, and noncardiovascular mortality in subjects with documented cardiovascular disease. After adjustment for systolic blood pressure, cholesterol, body mass index, cigarette smoking, and use of antihypertensive agents, they found that glucose was a strong, independent predictor of mortality. However, the relations for men and women were qualitatively different. For men, adjusted mortality risk increased very rapidly through the normal range (from 4.12% at 3.89 mmol/liter (70 mg/dl) to 12.26% at 5.55 mmol/liter (100 mg/dl)) and was flat at 12.26% thereafter. For women, risk was flat at 3.65% through the normal range and then increased rapidly, reaching 8.34% at 6.99 mmol/liter (126 mg/d), but increased much more slowly thereafter. Exactly analogous relations held for cardiovascular mortality. For men and women combined, noncardiovascular mortality increased from 1.82% at 3.89 mmol/liter to 2.06% at 5.55 mmol/liter to 2.29% at 6.99 mmol/liter (p for trend = 0.009). These findings suggest that although 5.55 mmol/liter (normal) may be a useful mortality risk division (albeit with different implications for the two sexes), 6.99 mmol/liter (diabetic) is not, especially for men.     

Homocysteine, folate, vitamin B12, and cardiovascular risk in Indians, Malays, and Chinese in Singapore

OBJECTIVE: To examine the hypothesis that the higher rates of coronary heart disease (CHD) in Indians (South Asians) compared with Malays and Chinese is partly attributable to differences in blood concentrations of homocysteine, and related blood concentrations of folate and vitamin B12. DESIGN: Cross sectional study of the general population. SETTING: Singapore. PARTICIPANTS: Random sample of 726 fasting subjects aged 30 to 69 years. MAIN RESULTS: Mean plasma total homocysteine concentrations did not show significant ethnic differences; values were Indians (men 16.2 and women 11.5 mumol/l), Malays (men 15.0 and women 12.5 mumol/l), and Chinese (men 15.3 and women 12.2 mumol/l). Similarly, the proportions with high plasma homocysteine (> 14.0 mumol/l) showed no important ethnic differences being, Indians (men 60.0 and women 21.9%), Malays (men 53.9 and women 37.8%), and Chinese (men 56.6 and women 30.6%). Mean plasma folate concentrations were lower in Indians (men 8.7 and women 10.9 nmol/l) and Malays (men 8.5 and women 10.8 nmol/l), than Chinese (men 9.7 and women 13.8 nmol/l). Similarly, the proportions with low plasma folate (< 6.8 nmol/l) were higher in Indians (men 44.9 and women 36.6%) and Malays (men 45.3 and women 24.5%) than Chinese (men 31.4 and women 12.6%). Mean plasma vitamin B12 concentrations were lowest in Indians (men 352.5 and women 350.7 pmol/l), then Chinese (men 371.1 and women 373.7 pmol/l), and then Malays (men 430.5 and women 486.0 pmol/l). CONCLUSION: While there were ethnic differences for plasma folate and vitamin B12 (in particular lower levels in Indians), there was no evidence that homocysteine plays any part in the differential ethnic risk from CHD in Singapore and in particular the increased susceptibility of Indians to the disease.     

Cardiovascular Health Metrics and All-cause and Cardiovascular Disease Mortality Among Middle-aged Men in Korea: The Seoul Male Cohort Study

Objectives

This study estimated the association of cardiovascular health behaviors with the risk of all-cause and cardiovascular disease (CVD) mortality in middle-aged men in Korea.

Methods

In total, 12 538 men aged 40 to 59 years were enrolled in 1993 and followed up through 2011. Cardiovascular health metrics defined the following lifestyle behaviors proposed by the American Heart Association: smoking, physical activity, body mass index, diet habit score, total cholesterol, blood pressure, and fasting blood glucose. The cardiovascular health metrics score was calculated as a single categorical variable, by assigning 1 point to each ideal healthy behavior. A Cox proportional hazards regression model was used to estimate the hazard ratio of cardiovascular health behavior. Population attributable risks (PARs) were calculated from the significant cardiovascular health metrics.

Results

There were 1054 total and 171 CVD deaths over 230 690 person-years of follow-up. The prevalence of meeting all 7 cardiovascular health metrics was 0.67%. Current smoking, elevated blood pressure, and high fasting blood glucose were significantly associated with all-cause and CVD mortality. The adjusted PARs for the 3 significant metrics combined were 35.2% (95% confidence interval [CI], 21.7 to 47.4) and 52.8% (95% CI, 22.0 to 74.0) for all-cause and CVD mortality, respectively. The adjusted hazard ratios of the groups with a 6-7 vs. 0-2 cardiovascular health metrics score were 0.42 (95% CI, 0.31 to 0.59) for all-cause mortality and 0.10 (95% CI, 0.03 to 0.29) for CVD mortality.

Conclusions

Among cardiovascular health behaviors, not smoking, normal blood pressure, and recommended fasting blood glucose levels were associated with reduced risks of all-cause and CVD mortality. Meeting a greater number of cardiovascular health metrics was associated with a lower risk of all-cause and CVD mortality.     

Cardiorespiratory fitness, all-cause mortality, and risk of cardiovascular disease in Trinidadian men--the St James survey

BACKGROUND: This study examined whether cardiorespiratory fitness is a risk factor for cardiovascular disease, myocardial infarction, and all-cause mortality in a low- to middle-income Trinidadian community of African, South Asian Indian, and European origin. Those of Indian descent have a distinctively high rate of myocardial infarction. METHODS: The St James Study is a prospective total community survey located in Port-of-Spain, Trinidad, West Indies. A random sample of 626 men aged 35-69 years, without angina of effort, previous myocardial infarction, partial or complete atrio-ventricular conduction defect, complete heart block, or exercise-induced asthma, was used for the assessment of cardiorespiratory fitness by cycle ergometry. Surveillance for morbidity and mortality was maintained for an average of 7.3 years. RESULTS: When the subjects were grouped into those with an age- and fat-free mass-adjusted peak oxygen uptake above and below the mean of 60.4 mmol/min (1.34 l/min), the hazard ratios (below/above) (95% confidence interval) for all-cause mortality, cardiovascular disease incidence, and incidence of myocardial infarction, after allowance for conventional cardiovascular risk factors, were 2.08 (1.23-3.52), 2.13 (1.22-3.69), and 2.36 (0.84-6.67), respectively. For those unable to achieve a level of work requiring an oxygen uptake of 67 mmol/min (1.5 l/min) during progressive exercise, the respective hazard ratios were 3.49 (1.57-7.76), 2.29 (1.21-4.33), and 5.45 (1.22-24.34). Indian ethnicity remained a predictor of myocardial infarction after allowance for cardiorespiratory performance. CONCLUSION: Low cardiorespiratory fitness is a risk factor for cardiovascular disease morbidity and mortality in the low- to middle-income developing community of Trinidad.     

Central obesity, insulin resistance, syndrome X, lipoprotein(a), and cardiovascular risk in Indians, Malays, and Chinese in Singapore.

STUDY OBJECTIVE: To examine the hypothesis that the higher rates of coronary heart disease (CHD) in Indians (South Asians) compared with Malays and Chinese is at least partly explained by central obesity, insulin resistance, and syndrome X (including possible components). DESIGN: Cross sectional study of the general population. SETTING: Singapore. PARTICIPANTS: Random sample of 961 men and women (Indians, Malays, and Chinese) aged 30 to 69 years. MAIN RESULTS: Fasting serum insulin concentration was correlated directly and strongly with body mass index (BMI), waist-hip ratio (WHR), and abdominal diameter. The fasting insulin concentration was correlated inversely with HDL cholesterol and directly with the fasting triglyceride concentration, blood pressures, plasminogen activator inhibitor 1 (PAI-1), and tissue plasminogen activator (tPA), but it was not correlated with LDL cholesterol, apolipoproteins B and A1, lipoprotein(a), (Lp(a)), fibrinogen, factor VIIc, or prothrombin fragment (F)1 + 2. This indicates that the former but not the latter are part of syndrome X. While Malays had the highest BMI, Indians had a higher WHR (men 0.93 and women 0.84) than Malays (men 0.91 and women 0.82) and Chinese (men 0.91 and women 0.82). In addition, Indians had higher fasting insulin values and more glucose intolerance than Malays and Chinese. Indians had lower HDL cholesterol, and higher PAI-1, tPA, and Lp(a), but not higher LDL cholesterol, fasting triglyceride, blood pressures, fibrinogen, factor VIIc, or prothrombin F1 + 2. CONCLUSIONS: Indians are more prone than Malays or Chinese to central obesity with insulin resistance and glucose intolerance and there are no apparent environmental reasons for this in Singapore. As a consequence, Indians develop some but not all of the features of syndrome X. They also have higher Lp(a) values. All this puts Indians at increased risk of atherosclerosis and thrombosis and must be at least part of the explanation for their higher rates of CHD.     

Geographical variations in blood pressure in British men and women

Geographical variations in blood pressure have been studied using an automatic sphygmomanometer in 2596 men and women aged 25-29, 40-44 and 55-59 living in nine British towns. In males aged 40-59, systolic blood pressure showed a range in age-adjusted town means of 9.0 mmHg (p less than 0.05); in females the difference of 8.6 mmHg was not significant (p = 0.14). Mean arterial pressure (MAP) and diastolic at age 40-59 were significantly different between towns for both sexes. Differences at age 25-29 were of a similar magnitude, and the mean town blood pressures at 25-29 correlated highly with those at 40-59 [systolic; males r = 0.74 (p less than 0.05), females r = 0.65 (p = 0.059)]. The ranking of town blood pressures in an earlier study was reflected in the present study, but stronger associations were observed with cardiovascular mortality. It is concluded that geographical blood pressure variations in Britain are established by age 25-29 years.     

Predictors of cardiovascular events and mortality in the Systolic Hypertension in the Elderly Program pilot project

Do the established cardiovascular risk factors for younger persons remain important predictors of cardiovascular disease events and mortality in those who are older? The authors examined this question in the Systolic Hypertension in the Elderly Program pilot project which prospectively followed 551 men and women 60 years of age and older with pretreatment systolic blood pressure greater than or equal to 160 mmHg and diastolic blood pressure less than 90 mmHg who were enrolled between May 1981 and July 1982. Mean age was 72 years, 37% were men, 82% were white, and 24% had attended college. The vital status of all 551 participants was known at the end of follow-up, an average of 34 months after entry; there were 39 deaths from all causes, 66 first cardiovascular events, 18 strokes, and 20 episodes of myocardial infarction/sudden death. Univariate Cox proportional hazard analysis revealed that age was a predictor (p less than 0.05) of all-cause mortality, first cardiovascular event, and stroke. Less than college education was a predictor of all-cause mortality and first cardiovascular event, smoking was a predictor of first cardiovascular event and myocardial infarction/sudden death, cholesterol was a predictor of first cardiovascular event, and lower body mass index was a predictor of increased all-cause mortality. After adjustment for covariables, age, lower education, lower body mass index, and baseline electrocardiographic abnormalities were significant predictors of all-cause mortality, and age, lower education, history of cardiovascular event, and smoking remained significant predictors of first cardiovascular event. Sex was not a risk factor, and the ability to examine hypertension as a risk factor was impaired by the fact that the entire cohort had systolic hypertension at baseline, and most were treated. These findings, combined with prior evidence, suggest that smoking, low education level, and perhaps serum cholesterol are risk factors for cardiovascular disease in the elderly. Although the excess risk conveyed by these factors is large, its reversibility needs to be demonstrated by intervention studies.     

Tea consumption. relationship to cholesterol, blood pressure, and coronary and total mortality.

BACKGROUND AND METHODS. The relation of tea to cholesterol, systolic blood pressure, and mortality from coronary heart disease and all causes was studied in 9,856 men and 10,233 women without history of cardiovascular disease or diabetes. All men and women 35-49 years of age from the county of Oppland (Norway) were invited to participate; the attendance rate was 90%. RESULTS. Mean serum cholesterol decreased with increasing tea consumption, the linear trend coefficient corresponded to a difference of 0.24 mmol/liter (9.3 mg/dl) in men and 0.15 mmol/liter (5.8 mg/dl) in women between drinkers of less than one cup and those of five or more cups/day, when other risk factors were taken into account. Systolic blood pressure was inversely related to tea with a difference between the same two tea groups of 2.1 mm in men and 3.5 mm in women. Altogether 396 men and 237 women died from all causes, and of these 141 and 18, respectively, died from coronary heart disease during the 12-year follow-up period. The mortality rate was higher (not statistically significant) among persons drinking no tea or less than one cup compared with persons drinking one or more cups/day. This applies to men and women and to coronary heart disease and all-cause mortality. For men, the relative risk (one or more versus less than one cup) for coronary death from Cox regression was 0.64 (95% CI:0.38, 1.07).     

Obesity, Hypertension, Hypercholesterolemia and Diabetes Mellitus in Women Aged 20-69, Living in a Highland Community of Crete

Risk factors for coronary heart disease were studied in a femalepopulation aged 20 to 69 years living in a highland communityof Crete. 375 women participated in the study. Mean value oftotal cholesterol was 6.23 mmol/l, of HDL-cholesterol 1.41 mmol/l,of serum triglycerides 1.58 mmol/l, of serum glucose 5.36 mmol/l,of systolic blood pressure 130.64 mmHg and of diastolic bloodpressure 78.07 mmHg. 46% of the study population had a bodymass index higher than 27. Upon multiple regression analysis,the body mass index correlated positively and independentlyof age with serum lipid level and the systolic and diastolicblood pressure. The results of this study agree with data fromother studies suggesting an increase in frequency of coronaryheart disease risk factors in Crete over the past 20 years.     

White blood cell count and risk for all-cause, cardiovascular, and cancer mortality in a cohort of Koreans

The authors conducted a 10-year prospective cohort study of mortality in relation to white blood cell counts of 437,454 Koreans, aged 40-95 years, who received health insurance from the National Health Insurance Corporation and were medically evaluated in 1993 or 1995, with white blood cell measurement. The main outcome measures were mortality from all causes, all cancers, and all atherosclerotic cardiovascular diseases (ASCVD). Hazard ratios and 95% confidence intervals were calculated using Cox proportional hazards models with adjustment for age and potential confounders. During follow-up, 48,757 deaths occurred, with 15,507 deaths from cancer and 11,676 from ASCVD. For men and women, white blood cell count was associated with all-cause mortality and ASCVD mortality but not with cancer mortality. In healthy nonsmokers, a graded association between a higher white blood cell count and a higher risk of ASCVD was observed in men (highest vs. lowest quintile: hazard ratio = 2.10, 95% confidence interval: 1.50, 2.94) and in women (hazard ratio = 1.35, 95% confidence interval: 1.17, 1.56). In healthy smokers, a graded association between a higher white blood cell count and a higher risk of ASCVD was also observed in men (highest vs. lowest quintile: hazard ratio = 1.46, 95% confidence interval: 1.25, 1.72). These findings indicate that the white blood cell count is an independent risk factor for all-cause mortality and for ASCVD mortality.     

Migration, blood pressure pattern, and hypertension: the Yi Migrant Study.

Rural-urban migration provides an ideal opportunity to examine the effects of environment and genes on blood pressure. The effect of migration on the Yi people of China was studied. The Yi people live in a remote mountain area in southwestern China. In 1989, blood pressure was measured in 14,505 persons (8,241 Yi farmers, 2,575 urban Yi migrants, and 3,689 Han urban residents) aged 15-89 years. Different patterns were seen for men and women. Among the men, Yi farmers had the lowest mean blood pressure, the least rise in blood pressure with age (systolic blood pressure, 0.13 mmHg/year; diastolic blood pressure, 0.23 mmHg/year), and the lowest prevalence of hypertension (0.66%). In contrast, both Yi migrant men and Han men had higher levels of mean blood pressure, rise in blood pressure with age (Yi migrants: systolic pressure, 0.33 mmHg/year; diastolic pressure, 0.33 mmHg/year; Han: systolic pressure, 0.36 mmHg/year; diastolic pressure, 0.23 mmHg/year), and prevalence of hypertension (Yi migrants, 4.25%; Han, 4.91%). Among the women, however, mean systolic pressure was higher in Yi farmers than in Yi migrants or in Han. Diastolic pressure was similar among the three groups. However, the Yi farmer women's age-related rise in blood pressure (systolic pressure, 0.06 mmHg/year; diastolic pressure, 0.14 mmHg/year) and their prevalence of hypertension (0.33%) were lower than those in the other two groups. Yi migrant women had an intermediate rise in blood pressure with age (systolic pressure, 0.37 mmHg/year; diastolic pressure, 0.23 mmHg/year) and prevalence of hypertension (2.40%). Han women had the greatest rise in blood pressure with age (systolic pressure, 0.56 mmHg/year; diastolic pressure, 0.36 mmHg/year) and the highest prevalence of hypertension (4.76%). For both men and women, the above differences were only partially explained by age, body mass index, heart rate, smoking, and alcohol use. This study, using standardized methods, demonstrates an important effect of migration on rise in blood pressure with age and on the prevalence of hypertension.     

Coronary heart disease risk factors in sub-Saharan Africa: studies in Tanzanian adolescents.

STUDY OBJECTIVE--To assess the level of cardiovascular risk factors in young people in sub-Saharan Africa living in rural and urban settings. DESIGN--Cross sectional survey of the population aged 15 to 19 years. SETTING--Eight rural Tanzanian villages in three regions, and two districts in Dar es Salaam. PARTICIPANTS--664 males and 803 females in rural villages and 85 males and 121 females in the city. Response rates for total population were 74% to 94% in the rural areas and 60% in the city. MEASUREMENTS AND RESULTS--Measurements included blood pressure, body mass index, serum lipids, and blood glucose concentrations (fasting and two hours after 75 g glucose). Blood pressure was slightly but significantly higher in young women than in young men (115/67 mmHg versus 113/65 mmHg) and increased significantly with age. Only 0.4% subjects had blood pressure greater than 140 and/or 90 mmHg. There were no urban-rural differences. Body mass index was higher in females (mean (SD) 20.3 (2.8) kg/m2) than males (18.5 (2.1)). Overweight was found in only 0.6% at age 15 years but 5.4% at age 19 years. Serum cholesterol concentrations were low at 3.5 mmol/l in males and 3.7 mmol/l in females. Only 7% had values above 5.2 mmol/l. The highest concentrations were found in the city and in Kilimanjaro, the most prosperous rural region. Serum triglycerides were 1.0 (0.5) mmol/l in males and 1.1 (0.5) mmol/l in females, and were highest in the city dwellers. Diabetes was rare (0.28% males, 0.12% females) but impaired glucose tolerance was present in 4.7% and 4.1% respectively. Drinking alcohol was equally prevalent in males and females, reaching 30% at age 19 years. Only 0.4% of females smoked compared with 7.3% of males. Smoking was commoner in rural areas that in the city. CONCLUSIONS--Several risk factors for cardiovascular disease were found in Tanzanian adolescents, but levels were much lower than in studies reported from developed nations. The challenge is to maintain these low levels as the population becomes more urbanised and more affluent.     

Patterns of physical activity and relationship with risk markers for cardiovascular disease and diabetes in Indian,Pakistani, Bangladeshi and European adults in a UK population

BACKGROUND: Differences in level of physical activity between European, Indian, Pakistani and Bangladeshi populations living in the UK might contribute to differences in the prevalence of diabetes and cardiovascular disease risk markers that exist in these populations. METHODS: Type and level of physical activity (measured by a multidimensional index) and its relationship with selected cardiovascular disease and diabetes risk factors were assessed in a cross-sectional, population-based study of European, Indian, Pakistani and Bangladeshi men and women, aged 25-75, resident in Newcastle upon Tyne. RESULTS: Europeans were found to be more physically active than Indians, Pakistanis or Bangladeshis. On our physical activity index 52 per cent of European men did not meet current guidelines for participation in physical activity compared with 71 per cent of Indians, 88 per cent of Pakistanis and 87 per cent of Bangladeshis. Similar findings are reported for women. In particular, European men and women participated more frequently in moderate and vigorous sport and recreational activities. In general, level of physical activity was inversely correlated with body mass index (BMI), waist measurement, systolic blood pressure, and blood glucose and insulin in all ethnic groups, but did not correlate with high-density lipoprotein (HDL) cholesterol. CONCLUSIONS: South Asians in Newcastle report significantly lower levels of habitual physical activity than Europeans. This is likely to contribute to the higher levels of diabetes and cardiovascular risk in these populations. Measures to increase physical activity in these populations are urgently needed.     

Prevalence of Selected Intermediate Risk Factors for Non-communicable Diseases in an Apparently Healthy Indian Community in KwaZulu-Natal,South Africa

South Africa, burdened with the emerging chronic diseases, is home to one of the largest migrant Indian population, however, little data exists on the risk factors for non-communicable diseases in this population. The aim of this study was to determine the prevalence of yet undiagnosed selected intermediate risk factors for non-communicable diseases among the Indian population in KwaZulu-Natal. We randomly selected 250 apparently healthy Indians, aged 35–55 years, living in KwaDukuza to participate in this study. Clinical and anthropometric measurements were taken under prescribed clinical conditions using Asian cut-off points. Pearson correlations was used to detect associations between anthropometric and clinical risk markers. A large percentage of participants’ systolic blood pressure fell within the normal range. Diastolic blood pressure was >85 mmHg for 61 % of the participants and triglyceride levels were >1.69 mmol/L for 89 % of the participants’; 94 % of the women and 87 % of the men were classified as centrally obese. Raised fasting blood glucose was seen in 39 % of participants’. Waist circumference and body mass index showed statistically significant associations with all clinical risk markers except for diastolic blood pressure. Our findings suggest that the use of ethno specific strategies in the management of the disease profile of South African Indians, will enable the South African health system to respond more positively towards the current trend of increased metabolic and physiological risk factors in this community. Moreover, key modifiable behaviours such as increased physical activity and weight reduction may improve most of these metabolic abnormalities.