Cardiovascular risk factors among black schoolchildren: comparisons among four Know Your Body studies

Baseline cardiovascular risk factor variables were obtained from 1,041 black District of Columbia children in Grades 4-6 as part of a Know Your Body evaluation project. Screening included height, weight, triceps skinfold measurements, systolic and diastolic blood pressures, step-test for fitness, serum cholesterol, high-density lipoprotein cholesterol and thiocyanate. Results were compared with those in three other Know Your Body studies, Bronx, New York, Westchester, New York, and Los Angeles, and indicated that District of Columbia black children are more likely to have high cholesterol levels and to fail the fitness test than black children in the other studies. In the District of Columbia, obese children had significantly higher total serum cholesterol, systolic, diastolic, and high-density lipoprotein levels, and were less fit than other District of Columbia children; almost three-fourths of all of the children had one or more risk factors. Socioeconomic status was negatively correlated with diastolic blood pressure, skinfold thickness, and cholesterol levels and was positively correlated with high-density lipoprotein cholesterol. Rates of obesity and diastolic blood pressure were consistent with Bronx and Westchester comparisons suggesting that socioeconomic status interacts with ethnicity to determine risk factor levels. The existence of children with multiple risk factors in all of the Know Your Body studies supports the need for early intervention.     

Blood pressure and its relationship to plasma lipids and lipoproteins in children: Cross-sectional data from the fels longitudinal study

Interrelationships of blood pressure and plasma lipid-lipoproteins were examined in cross-sectional data from 62 boys and 57 girls, aged 9 to 18 years. These white children, unselected on the basis of blood pressure or lipid-lipoproteins, are of middle socioeconomic class, live in southwestern Ohio, and are participants in the Fels Longitudinal Study. After covariance adjusting for age and measures of body size and ponderosity, girls in the lowest C-HDL quartile had higher mean systolic blood pressure than those in the top quartile (P = 0.003). Girls in the highest blood pressure quartile had high-density lipoprotein cholesterol (C-HDL) levels lower than those in the lowest blood pressure quartile although the difference was not statistically significant (P = 0.13). There was a significant negative partial correlation (r = ?0.31; P = 0.02) in girls between systolic blood pressure and C-HDL levels adjusted for age, fatness, and body size. There were no other consistent, significant relationships between lipid-lipoproteins and blood pressures observed. Associations between lipid-lipoproteins and blood pressure may have important health consequences, since both blood pressure and lipoprotein elevations contribute, synergistically, to coronary heart disease risk, and since both generally maintain their rank order over time from childhood.     

Prevalence of coronary heart disease risk factors in an urban black population: the Minnesota Heart Survey, 1985

A cross-sectional study of a sample of Minnesota black urban residents was conducted in 1985 to develop cardiovascular risk profiles. Participants were evaluated during a home interview (N = 1,254, 78% participation) and a survey center visit (N = 1,052, 65% participation). Black men had significantly higher mean systolic and diastolic blood pressure than Black women (129.7/80.9 vs 124.8/77.3, respectively). Age-specific values for systolic and diastolic blood pressure were greater in men than women for all age categories. Men were more likely to have uncontrolled hypertension or to be unaware of their hypertension than women in all age categories. Women had significantly higher mean total and high-density lipoprotein cholesterol values than men (202.1 and 56.1 mg/dl vs 193.2 and 48.7 mg/dl, respectively). Age-specific values for total and high-density lipoprotein cholesterol values were greater in women than men for all age categories except the 35-44 age group. Men were significantly more likely to be current cigarette smokers (43.3% vs 33.2%) and to have higher cigarette consumption per day (17 vs 14) than women. The major risk factors for cardiovascular disease (with the exception of smoking) were lower in the Minnesota study in 1985 than in the National Health and Nutrition Examination Survey in 1976-1980. These lower levels may also be a component in the decline of cardiovascular disease mortality rates among Blacks.     

Serum lipid levels in elementary and junior high school children and their relationship to relative weight

Serum lipid levels were measured in 2,626 schoolchildren ages 7 to 15 years in three elementary schools and one junior high school in a suburban area of Osaka during 1984-1985. The mean cholesterol levels increased with age in boys ages 7 to 10 years (from 156 to 177 mg/dl) and then decreased at age 13, after which the levels again increased slightly until age 15. Girls showed a similar tendency with a peak at age 10 and a minimum at age 12. Cholesterol levels were significantly lower in junior high school boys (a mean of 154-161 mg/dl for ages 13-15 years) than in girls of the same age or in boys and girls ages 10 to 12 years in the upper grades of elementary school. Cholesterol and triglyceride levels tended to be lower or the high-density lipoprotein cholesterol levels higher in elementary schools where boys and girls engaged in physical exercise than in schools where the children were not strongly encouraged to exercise. About 50% of the hypertriglyceridemic children were obese.     

Nutrient intake, lipids, and lipoprotein cholesterols in black and white children: the Lipid Research Clinics Prevalence Study

Our specific aim was to assess differences in nutrient intake and in lipids and lipoprotein cholesterols between blacks and whites in 259 black children (129 boys, 130 girls) and in 811 white children (424 boys, 387 girls) ages 5-19. The nutrient intake data were obtained by 24-hr recall from the Houston and Cincinnati Lipid Research Clinics. The fundamental nutrient differences between blacks and whites were in total calories and in calories per kilogram of body weight, both of which were uniformly and significantly lower among black than white boys and generally, but less consistently and significantly, lower among black than white girls. No racial differences in total cholesterol or cholesterol intake per kilogram body weight were observed. After statistically controlling for education of the head of household, there were no consistent significant racial differences in Quetelet index. There was no significant independent effect of education of head of household on the children's caloric intake and racial differences in socioeconomic status did not appear to systematically account for differences in total energy intake. In aggregate, black children had lower triglyceride and very-low-density lipoprotein cholesterol levels, and higher levels of high-density lipoprotein cholesterol than whites; there were no significant differences by race in low-density lipoprotein cholesterol levels. Race was a significant independent explanatory variable for high-density lipoprotein cholesterol levels (higher in blacks) and for very-low-density lipoprotein and triglyceride levels (higher in whites) (P less than 0.005), after covariance adjusting for education of head of household, sex, age, Quetelet index, calories, saturated fat (g/day/kg body wt), and clinic. Lower caloric intake among blacks compared with whites, the major nutrient difference in the current study, did not account for differences in lipoprotein cholesterol levels between the two groups.     

Different worlds, different tasks for health promotion: comparisons of health risk profiles in Chinese and Finnish rural people.

The aim of this study was to compare cardiovascular risk factors of working-aged people in Chinese and Finnish rural villages. The surveys were carried out in 1989 in Tianjin, China, and in Kuopio, Finland. Altogether, 897 Chinese inhabitants and 795 Finnish subjects participated in the surveys. Health behaviours were recorded, and height, weight, blood pressure, heart rate and serum lipids were measured. Generally Finns had a significantly higher mean body-mass index, systolic and diastolic blood pressures, and serum total cholesterol, low-density lipoprotein cholesterol, and total cholesterol/high-density lipoprotein ratio than the Chinese. However, no difference was seen between Chinese and Finnish women in diastolic blood pressure and serum triglycerides. Lower high-density lipoprotein cholesterol levels were observed in Finnish men than in Chinese men, whereas a higher mean level was shown in Finnish women than in Chinese women. There were significantly higher mean heart rates and prevalence of smoking in Chinese than in Finnish populations. More people who were overweight, obese and hypertensive were found in the Finnish than in the Chinese populations. Most of the Finns had two or more cardiovascular risk factors compared with the Chinese, the majority of whom were in the group with less than two risk factors. In conclusion, the risk profiles are clearly somewhat different in these two countries. A major task for the Chinese health policy and health care system is to decrease smoking and to prevent obesity and hypertension. In Finland, the biggest task seems to be the reduction of weight and lipid abnormalities, and the prevention of hypertension.     

Effects of levonorgestrel-releasing intrauterine system on glucose and lipid metabolism: a 1-year follow-up study

PURPOSE: This prospective study aimed to assess the possible effects of the levonorgestrel-releasing intrauterine system (LNG-IUS) on serum lipids and fasting blood glucose levels over a period of 1 year. METHODS: Forty-eight premenopausal women, attending our gynecology clinic with the complaint of menorrhagia, were enrolled in the study. Systolic and diastolic blood pressures were recorded. Serum concentrations of total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and fasting plasma glucose (FPG) levels were tested before (pretreatment group) and 1 year later following insertion (on-treatment group). Baseline mean parameters were compared with mean parameters at 1 year for statistical significance using paired samples t-test. RESULTS: Thirty-three (68.75%) women were eligible for control in the on-treatment group. Mean age of the patients was 44.34+/-7.59 years. The study results showed that mean FPG level was significantly increased, whereas mean diastolic blood pressure was significantly decreased. Although mean systolic blood pressure tended to decrease and HDL-C concentrations to increase, these changes from baseline levels were insignificant. There were no significant changes in mean TG, TC, VLDL, LDL, AST and ALT. DISCUSSION: The only significant unfavorable effect observed was an increase in FPG level. Since it did not rise to risky values, but alerted us for the high risk patients for glucose intolerance before insertion. The LNG-IUS can be regarded as being safe in their effects on lipid metabolism, blood pressure and liver function tests.     

Distributions of total cholesterol, triglycerides, and high-density lipoprotein cholesterol in Israeli Jewish children of different geographic-ethnic origins, ages 9-17 years

To determine age and ethnic patterns of blood lipid levels in childhood and adolescence and to extend previous adult and late adolescent Israeli data to prepubertal ages, the levels of plasma total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG) were determined among 1,153 schoolchildren in the area of Petah-Tikva. Half of the children were born to immigrants from Yemen. Among boys, TC levels progressively decreased as age increased from 10-11 to 14-15 years (159 to 142 mg/dl). The age-specific TC and HDL-C means among boys are compatible with an initial swift fall with age, followed by a rise restricted to TC during puberty. Among girls, progressively lower means through ages 12-13 and increasingly higher ones for older age groups are also compatible with puberty-determined changes, previously observed in American cohorts. The differences in TC were only partly accounted for by lower HDL-C means at higher ages (52 mg/dl in the youngest and 45 mg/dl in the oldest age group, respectively, among boys, compared with 53 mg/dl for girls at both ages 9 and 16-17). TG levels in boys, but not in girls, showed age differences paralleling those found for HDL-C, but in an inverse direction. TC means were lower as age increased only among female offspring of European-born Jews (159 to 148 mg/dl, ages 9-12 compared with ages 13-17), a phenomenon that requires further study. Overall, TC and HDL-C were clearly higher among girls than boys beginning at ages 12-13, with little or no sex differences in TG. The sex differences in TC, contrary to previous studies, were not fully accounted for by HDL-C sex differences. The ethnic variability paralleled previous findings in Israeli adults and adolescents, showing low TC levels among male offspring of Yemenite and other Asian-born fathers. The ethnic differences among girls were small. No specific pattern of age-related lipid changes was found in the group of Yemenite origin, who represented offspring of parents with notoriously low levels of coronary heart disease incidence.     

National report on the association of serum vitamin D with cardiometabolic risk factors in the pediatric population of the Middle East and North Africa (MENA): The CASPIAN-III Study

ObjectivesAs the first, to our knowledge, nationwide study in the Middle East and North Africa (MENA), this study aimed to investigate the association of serum 25 hydroxy vitamin D [25(OH)D] levels with cardiometabolic risk factors in a nationally representative sample of the pediatric population in Iran. The second objective was to provide the prevalence of hypovitaminosis D and the percentiles of serum 25(OH)D in the study population.MethodsThis national population-based study was conducted among 1100 Iranian students living in 27 provinces in Iran. The association of 25(OH)D with each cardiometabolic risk factor was determined after adjustment for age, gender, body mass index, and waist circumference.ResultsParticipants consisted of 1095 students (52% boys) with a mean age of 14.74 ± 2.61 y. The median 25(OH)D level corresponded to a vitamin D insufficiency level: 12.70 ng/mL in boys and 13.20 ng/mL in girls. Overall, 40% of participants were vitamin D deficient, and 39% had vitamin D insufficiency. There were no significant differences in these findings between boys and girls. Adjusted regression analysis revealed a significant weak inverse association of 25(OH)D with systolic blood pressure, diastolic blood pressure, total cholesterol, and low-density lipoprotein cholesterol. This association was significantly positive with high-density lipoprotein cholesterol, but not with fasting plasma glucose and metabolic syndrome.ConclusionWe found a considerably high prevalence of hypovitaminosis D in the pediatric population of a sunny region. Our findings also revealed an association of hypovitaminosis D with many cardiometabolic risk factors from childhood; these associations were independent of obesity indexes. It is of special concern that the highly prevalent disorders of low 25(OH)D and low high-density lipoprotein cholesterol in children and adolescents of the MENA region had significant association. The clinical importance of our findings needs to be confirmed in longitudinal studies.     

Physical activity and cardiovascular risk: a cross-sectional study of middle-aged premenopausal women

The relationship between self-reported physical activity and cardiovascular risk factors was evaluated in a population-based sample. The sample included 541 premenopausal women recruited for a study of the natural history of risk factor change associated with change in sex hormone status. Physical activity was assessed using the Paffenbarger Activity Questionnaire. Women were classified according to quartile of weekly energy expenditure into groups of 0-500, 501-999, 1,000-1,999, and 2,000 kcal or greater. Results showed that the more active the women, the lower their blood pressure and heart rate. More active women had lower cholesterol and triglycerides, and higher high-density lipoprotein (HDL) cholesterol. Tricep and suprailiac skinfolds, fasting insulin, and insulin/glucose levels were also lower among the more active women. When the analysis was repeated controlling for the effect of education and body mass index, the statistical test for linear trend remained significant except for the trend for heart rate, total cholesterol, and triglycerides. Women reporting activity of 1,000 kcal/week had higher high-density lipoprotein cholesterol and lower diastolic blood pressure, body mass index, skinfolds, fasting insulin, and fasting insulin/glucose ratios compared with women reporting lower levels of activity. Only those women who reported 2,000 kcal/week had significantly lower total cholesterol, triglycerides, and low-density lipoprotein cholesterol, and higher HDL2 cholesterol; women reporting less activity did not differ with regard to these lipids and lipoproteins. The study suggests that physical activity is associated with improved cardiovascular risk profiles among middle-aged women and that the beneficial effects of activity are seen at different levels for specific risk factors.     

Relationship between baseline risk factors and coronary heart disease and total mortality in the multiple risk factor intervention trial

The relationship between selected baseline risk factors and subsequent coronary heart disease (CHD) death and total mortality among participants in the Multiple Risk Factor Intervention Trial (MRFIT) was studied in order to determine (a) whether the three risk factors used to identify high-risk men for the trial were associated with CHD death; (b) whether other risk factors measured at baseline, especially lipoprotein cholesterol levels, were associated with CHD and total mortality; and (c) whether there were any differences between special intervention (SI) and usual care (UC) participants in the relationship of the specific levels of risk factors to CHD or total mortality. The three main risk factors (blood cholesterol, cigarette smoking, and diastolic blood pressure) and age were significantly associated with CHD mortality; age, diastolic blood pressure, and cigarette smoking were associated with total mortality. The risk score based on the multiple logistic equation developed from the Framingham Study was also strongly associated with CHD mortality. When the joint associations of selected baseline risk factors with CHD and total mortality were considered, age, diastolic blood pressure, cigarette smoking, and low- and high-density lipoprotein cholesterol were significantly associated with CHD mortality; age, cigarette smoking, and low-density lipoprotein cholesterol were positively associated with total mortality. Systolic blood pressure significantly improved the prediction of CHD mortality for SI and UC men when it was added to a regression model that included age, diastolic blood pressure, cigarettes smoked per day, body mass index, and lipoprotein levels, but improved the prediction of total mortality only for SI men. In similar analyses, serum thiocyanate improved the prediction of both CHD and total mortality for UC men. Among SI men the improved prediction gained by considering serum thiocyanate was less pronounced and not significant for CHD death. This latter finding may be due in part to the changes made in smoking behavior by SI participants during the course of the study. The estimated regression coefficients for CHD and total mortality endpoints were not significantly different between the SI and UC groups.     

Ethnicity and other characteristics predictive of coronary heart disease in a developing community: principal results of the St James Survey, Trinidad

A ten-year community survey was undertaken to investigate the high coronary heart disease (CHD) incidence among people of Indian (South Asian) descent in Trinidad, West Indies. Of 2491 individuals aged 35-69 years, 2215 (89%) were examined and 2069 (83%) found to be clinically free of CHD at baseline. After exclusion of 71 of minority ethnic groups, 786 African, 598 Indian, 147 European and 467 adults of Mixed descent were followed for CHD morbidity and mortality. In both sexes, adults of Indian origin had higher prevalence rates of diabetes mellitus, a low concentration of high-density lipoprotein (HDL) cholesterol, and recent abstinence from alcohol than other ethnic groups. Indian men also had larger skinfold thicknesses than other men. In participants free of CHD at entry, the age-adjusted relative risk of a cardiac event believed due to CHD was at least twice as high in Indian men and women as in other ethnic groups. In men, blood pressure, diabetes mellitus and low-density lipoprotein (LDL) cholesterol concentration were positively and independently related to risk of CHD, whereas alcohol consumption and HDL cholesterol concentration were inversely associated with risk after allowing for age and ethnic group. The ethnic contrasts in CHD persisted when these characteristics were taken into account. In the smaller sample of women, only ethnic group was predictive of CHD as defined. The failure of point estimates of risk to explain the high CHD incidence in Indians calls for focus on age of onset of risk and examination of other potential risk factors such as insulin concentration.     

The roles of insulin, obesity, and fat distribution in the elevation of cardiovascular risk factors in impaired glucose tolerance. The San Luis Valley Diabetes Study.

The objective of this study was to determine whether a less favorable risk factor pattern for cardiovascular disease among persons with impaired glucose tolerance could be explained by fasting insulin, obesity, and/or a central distribution of body fat. Between 1984 and 1988, cardiovascular risk factors were examined cross-sectionally in Hispanic and non-Hispanic white participants in the San Luis Valley Diabetes Study who had either impaired (n = 173) or normal (n = 1,107) glucose tolerance. Sex-specific analysis of covariance models were constructed to adjust risk factor levels for age, age and insulin, and age, insulin, body mass index, and centrality index. Both males and females with impaired glucose tolerance had higher age-adjusted mean diastolic blood pressures, heart rates, uric acid levels, and triglyceride levels and lower levels of high density lipoprotein (HDL) cholesterol and HDL3 cholesterol than normal subjects; differences were significant for all risk factors except HDL cholesterol and HDL3 cholesterol in males. Differences in diastolic blood pressure in males, and differences in heart rate and triglyceride in both sexes, remained significant after adjustment for all covariates. However, differences in uric acid in males and differences in diastolic blood pressure and HDL3 cholesterol in females were attenuated to borderline significance levels. Differences in uric acid and HDL cholesterol in females were diminished to nonsignificant levels, especially after adjustment for obesity-related measures. With few exceptions, fasting insulin did not appear to play a major role in accounting for differences in these risk factors. With adjustment, ethnic differences (Hispanic vs. non-Hispanic white) were smaller and were statistically significant less often than differences observed between impaired and normal glucose tolerant groups. The authors concluded that hyperinsulinemia, obesity, and a central body fat distribution accounted for some, but usually not all, of the less favorable cardiovascular risk factor pattern found in subjects with impaired glucose tolerance.     

Parental history of coronary heart disease, hypertension, diabetes, and stroke: Relationship to coronary heart disease risk factor variables in their adult children

Relationships of parental (familial) history of coronary heart disease, stroke, hypertension, and diabetes to major coronary heart disease (CHD) risk factors were examined in 738 adults (average age, 40 years) in the Cincinnati Lipid Research Clinics Princeton School study. Men reporting parental CHD had higher plasma triglyceride and higher systolic and diastolic blood pressure than comparison group men reporting no parental CHD, stroke, hypertension, or diabetes. Women reporting parental CHD had higher plasma triglycerides than comparison group women reporting no parental CHD, stroke, hypertension, or diabetes. Men reporting stroke in one parent had higher total plasma cholesterol and triglyceride levels than comparison men. Women reporting stroke in one parent had higher triglyceride levels than comparison group women. Women reporting hypertension in one parent had higher mean triglyceride and systolic blood pressure than comparison women. Men and women reporting diabetes in one parent had higher triglyceride than comparison adults. Matching men whose fathers had died of CHD with those whose fathers were free of CHD revealed significant increments in triglyceride levels, systolic, and diastolic blood pressure in the men with positive family history of CHD. Matching women whose fathers had died of CHD with those whose fathers were free of CHD revealed higher total plasma cholesterol, low-density lipoprotein cholesterol, and Quetelet index. In men, categorical assessment by CHD risk factor levels (low, intermediate, high), revealed that plasma triglycerides and systolic blood pressure were positively associated with a parental history of CHD, while high-density lipoprotein cholesterol was inversely related. In women, similar observations were made for triglycerides. Family history is a practical tool for identification of risk to CHD, hypertension, stroke, and diabetes. Serial risk factor measurements in offspring from CHD-, hypertension-, stroke-, and diabetes-positive families should have considerable utility in early recognition and documentation of CHD risk factor levels which, in turn, should facilitate primary intervention designed to ameliorate or prevent the development of CHD.     

The interaction of cigarette smoking, oral contraceptive use, and cardiovascular risk factor variables in children: the Bogalusa Heart Study.

Two separate surveys were conducted in a total biracial population of children ages 8-17 years to determine the effects of cigarette smoking and oral contraceptive use on blood pressure and serum lipids and lipoproteins. Information regarding smoking habits and oral contraceptive use was obtained from detailed questionnaires. For White boys and White and Black girls, a small but statistically significant decrease in diastolic blood pressure levels for cigarette smokers when compared to non-smokers was noted. A significant increase among cigarette smokers in beta-lipoprotein cholesterol, pre-beta-lipoprotein cholesterol, and triglycerides as well as a decrease in alpha-lipoprotein cholesterol was noted, especially for White girls. This change in lipoprotein levels for cigarette smokers was noted in both surveys. Oral contraceptive users had higher total cholesterol and beta-lipoprotein cholesterol and lower alpha-lipoprotein cholesterol than nonusers. After adjusting for oral-contraceptive use, particularly among White girls, cigarette smokers still demonstrated high pre-beta-lipoprotein cholesterol and lower alpha-lipoprotein cholesterol levels than non-smokers. These results suggest that the lipid and lipoprotein response to cigarette smoking and oral contraceptive use is to increase cardiovascular risk.     

Mortality among children and young persons in Sweden in relation to childhood socioeconomic group.

More than 1.5 million children in Sweden were followed up for the period 1961-1979 with respect to mortality. Mortality differences by socioeconomic group were studied for the age groups 1-19 years. Children in families of non-manual workers, both boys and girls, had a significantly lower mortality than children of manual workers and children of self employed persons. The socioeconomic differences in risk of dying were greater among boys than among girls. For boys, the socioeconomic differences grew smaller as the boys grew older.     

Prevalence of traditional and novel markers of cardiovascular disease risk in Scottish adolescents: socioeconomic effects

Information on the health status and physical activity of Scottish adolescents is limited. This study examines the prevalence of cardiovascular disease (CVD) risk in Scottish adolescents by socioeconomic status (SES). Participants were recruited from two high schools that differed in the SES of the students in attendance. The sample included 73 boys and 34 girls (16.4 ± 0.6 years). Variables included anthropometry, physical activity, physical fitness, blood pressure, diet, and 11 metabolic markers of CVD risk. Significant sex differences (P ≤ 0.01) were noted for stature, waist circumference, waist-hip ratio, physical activity, cardiorespiratory fitness, muscular power, sprint speed, and several CVD risk factors: high-density lipoprotein (HDL), low-density lipoprotein (LDL), interleukin-6 (IL-6), and C-reactive protein (CRP) levels. Boys from a lower SES had significantly higher levels of glucose and plasminogen activator inhibitor-1 (PAI-1) but lower levels of adiponectin compared with boys from a higher SES. Girls from a lower SES had significantly (P ≤ 0.01) higher glucose and PAI-1 levels but lower levels of insulin and adiponectin than girls from a higher SES. High fat diets, low physical activity levels, and elevated CRP and total cholesterol levels were the CVD risk factors most commonly identified as being at-risk levels in this cohort, regardless of sex or SES. SES differences were not consistently apparent, but several CVD risk factors were identified as elevated in this sample of adolescents, regardless of sex or SES.     

Physical fitness, physical activity, and cardiovascular disease risk factors in adolescents: the Oslo Youth Study

Aerobic fitness, resting pulse rate, and self-reported physical activity were examined along with prevalence of cardiovascular disease risk factors in a population-based study of 413 boys and 372 girls, ages 10 to 14 years. Cardiovascular fitness (VO2 max) was predicted from heart rate measured during submaximal bicycle exercise. For both genders, fitness level was significantly and inversely related to body weight, body mass index [weight in kilos/(height in meters)2], triceps skinfold thickness, systolic and diastolic blood pressure, and pulse rate and positively related to high-density lipoprotein/total cholesterol ratio and physical activity. In addition, fitness level was positively related to high-density lipoprotein cholesterol and negatively related to triglycerides in females; it was also negatively related to height, total cholesterol, and hematocrit in males. Analyses of covariance, controlling for sexual maturity ratings, revealed that students in the lowest quartiles of VO2 max had significantly higher body mass index and triceps skinfold thickness than students in the higher quartiles. After adjustment for body mass index and sexual maturity ratings, blood pressure and pulse rate in both genders were significantly higher among students in the lower quartiles of VO2 max than among the groups who scored higher on the fitness test. Higher levels of VO2 max were also associated with a more favorable lipid profile in females. In gender-specific multiple regression analysis, triceps skinfold thickness was the strongest predictor of VO2 max, followed by pulse rate. Our study provides evidence that higher levels of fitness are associated with more favorable risk profiles in adolescents.     

Race and diet in the overweight: association with cardiovascular risk in a nationally representative sample

OBJECTIVE: Because dietary differences may account for much of the racial and ethnic disparities in cardiovascular risk status, we evaluate the effect of race on cardiovascular risk after adjustment for dietary factors. METHODS: Prevalence of healthy diets in overweight U.S. adults (body mass index > or = 25 kg/m(2), age > or = 18 y) by race or ethnicity was determined by using 24-h dietary recalls from the National Health and Nutrition Examination Survey of 1999 to 2000. Dietary recalls included daily total calories, percentage of calories obtained from saturated fat, cholesterol, dietary fiber, and sodium and potassium intakes. Logistic regressions were used to evaluate the association between race/ethnicity, dietary factors, and cardiovascular risk markers (high levels of total cholesterol, C-reactive protein, systolic blood pressure, and diastolic blood pressure and low levels of high-density lipoprotein). RESULTS: The percentage of respondents who met healthy diet parameters ranged from 11.2 to 63.3. Non-Hispanic whites without diagnosed disease were less likely to have healthy diets than were African Americans or Hispanics, except with regard to cholesterol and fiber intake. After controlling for dietary factors, African American ethnicity was associated with a lower risk of hypercholesterolemia (odds ratio 0.587, 95% confidence interval 0.403 to 0.855), lower level of high-density lipoprotein (odds 0.440, 95% confidence interval 0.236 to 0.763), and a greater risk of high systolic blood pressure (odds ratio 2.383, 95% confidence interval 1.043 to 5.442) compared to whites. CONCLUSIONS: Differences in adherence to healthy diet parameters by race/ethnicity exist. However, after adjustment for diet and other modifiable factors, African Americans have a decreased risk of hypercholesterolemia and low level of high-density lipoprotein but an increased risk of systolic hypertension. Further research into the genetic basis for these differences is suggested.     

Physical development and lifestyle of Hong Kong secondary school students

BACKGROUND: Objectives of the present investigation were to study the growth and development of adolescents in Hong Kong, to analyze the interrelationship between their development and lifestyle, and to provide some helpful suggestions for lifestyle modification. METHODS: A total of 404 secondary students ages 12-18 years served as subjects. Morphological measures, blood pressure, blood lipids, aerobic fitness, and body composition were tested. A self-report questionnaire was administered to assess physical activity and dietary habits. RESULTS AND CONCLUSIONS: Systolic blood pressure and diastolic blood pressure increased with age, and a gender difference was noted. Body height and body weight increased with age. Total cholesterol showed a lowering trend with age, and high-density lipoprotein had a slight rise. The percentage body fat for boys decreased with age but increased for girls. The higher percentage of overweight and obesity was closely associated with physical inactivity and inappropriate food selection such as eating snacks or food rich in fat or cholesterol. Tailor-made physical activity and nutritional education programs should be designed for adolescents, especially girls during puberty.