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BACKGROUND. Recent studies have shown considerable variation in body fatness among children and adolescents defined as obese by a percentile rank for skinfold thickness. METHODS. We examined the relationship between percent body fat and risk for elevated blood pressure, serum total cholesterol, and serum lipoprotein ratios in a biracial sample of 3320 children and adolescents aged 5 to 18 years. Equations developed specifically for children using the sum of subscapular (S) and triceps (T) skinfolds were used to estimate percent fat. The S/T ratio provided an index of trunkal fat patterning. RESULTS. Significant overrepresentation (greater than 20%) of the uppermost quintile (UQ) for cardiovascular disease (CVD) risk factors was evident at or above 25% fat in males (32.2% to 37.3% in UQ) and at or above 30% fat in females (26.6% to 45.4% in UQ), even after adjusting for age, race, fasting status, and trunkal fat patterning. CONCLUSIONS. These data support the concept of body fatness standards in White and Black children and adolescents as significant predictors of CVD risk factors. Potential applications of these obesity standards include epidemiologic surveys, pediatric health screenings, and youth fitness tests.

BACKGROUND Adiponectin, an adipocytokine with beneficial biological functions relevant to cardiovascular (CV) diseases, and arterial stiffness, an indicator of vascular function, are considered to be important correlates of CV disease risk. Although racial (black-white) divergences in adiponectin and arterial stiffness are known, information is scant regarding the association between these two parameters among asymptomatic young adults within each race. METHODS As part of the Bogalusa Heart Study, arterial stiffness was examined noninvasively in terms of aorta-femoral pulse wave velocity (af-PWV) in 991 black and white nondiabetic subjects (72% white, 43% male) aged 24-44 years. RESULTS In a multivariate regression model by race that included adiponectin, age, sex, waist circumference, mean arterial pressure, heart rate, homeostasis model assessment of insulin resistance, low- and high-density lipoprotein cholesterols, triglycerides, and cigarette smoking, the significant predictors of af-PWV, in the order of entry, were: mean arterial pressure, age, smoking, and heart rate in both races, followed by adiponectin (inverse relation) in blacks. Further, after adjusting for mean arterial pressure, age, smoking, and heart rate, the odds ratio of finding excess af-PWV (top decile vs. the rest) in individuals with low adiponectin levels (bottom quartile vs. the rest) was significantly higher in blacks (OR: 2.5; 95% CI: 1.1-5.5), but not in whites (OR: 0.9; 95% CI: 0.5-1.9). CONCLUSIONS These findings suggest that the status of hypoadiponectinemia is an independent correlate of excess arterial stiffness in asymptomatic young black adults.

To alter the adverse natural course of coronary artery disease and its risk factors, primary prevention should begin in childhood.High serum cholesterol, LDL cholesterol (LDL-C) in particular, remains the major determinant of atherosclerotic process beginning in childhood. Selective cholesterol screening of children based on family history is inadequate. Tracking of childhood elevated cholesterol in conjunction with other risk factors into adulthood argues in favor of universal screening in the young. Further, individual adverse levels of LDL-C not only increase the incidence of adulthood dyslipidemia, but also markedly enhances the prevalence of obesity and hypertension seen in the adult population.Screening of all young individuals for serum cholesterol along with a cardiovascular risk factor profile is recommended. Cardiovascular disease remains a public health issue and identifying young individuals at risk is basic to prevention.

The Bogalusa Heart Study, a long-term population study with a continued relationship with a community, addresses the problem of capacity building in minority health research. The study was originally funded as a Specialized Center of Research-Arteriosclerosis (SCOR-A) by the National Heart Lung and Blood Institute (NHLBI). These centers were to conduct research on atherosclerosis, coronary artery disease (CAD), hypertension, diabetes mellitus, and complications of cardiovascular-renal disease as the major causes of deaths in the United States. From earlier research on atherosclerosis, we became interested in the underlying characteristics in early life that would eventually lead to clinical morbidity and mortality from heart disease. An observation at autopsy showed the degree of atherosclerotic involvement in human aortas, from young to older individuals (Figure 1). For example, at age 40 years, marked individual variability occurred in the severity and involvement with atherosclerotic disease. Some individuals showed very little disease, while almost 70% of the surface was diseased in others. Further studies on arterial wall matrix showed aortas from young individuals varied with the extent of disease and its chemical composition. This background stimulated an interest in studying children for early clinical evidence of major adult heart diseases. The Bogalusa Heart Study was begun in 1972 as an epidemiology study of cardiovascular risk factors in children and adolescents; it eventually evolved into observations of young adults. Bogalusa, LA, is a biracial (black/white) rural community 70 miles north of New Orleans, comparable to many other communities in southeastern United States.

Although parent-offspring associations of cardiovascular risk factor variables are known, the age-specific nature of this familial relationship is not clear.This aspect was examined in 727 unrelated children (mean age: 11.2 years) and their parents who participated in the Bogalusa Heart Study during their childhood (mean age: 11.3 years) and adulthood (mean age: 25.5 years).After adjusting for covariates, the mothers' childhood-offspring correlations were consistently higher than mothers' adulthood-offspring correlations for body mass index (BMI) [r = 0.45 vs. 0.32], systolic blood pressure (SBP) [r = 0.30 vs. 0.10], diastolic blood pressure (DPB) [r = 0.22 vs. 0.13] and low-density lipoprotein cholesterol (LDLC) [r = 0.20 vs. 0.11]. In contrast, high-density lipoprotein cholesterol (HDLC) and triglycerides did not show such age-specific trends in mother-offspring correlations. Corresponding father-offspring correlations showed similar patterns, but the differences were of lesser magnitude. Multiple regression analyses using offspring's risk factor variables as dependent variables revealed that parents' childhood obesity, blood pressure and LDLC levels were better predictors of the corresponding variables in the young offspring than parents' adulthood values. Further, sex of either parents or offspring made no difference in the above findings.The magnitude of the familial associations of cardiovascular risk factor variables between parents and offspring are influenced by age. Intrinsic genetic make-up, duration of exposure to environment and gene-environment interactions may play a role in this association.

Elevated serum triglyceride level is increasingly being recognized as an important indicator of cardiovascular risk. The distribution and correlates of serum triglycerides were examined in a biracial (black-white) community-based sample of 1342 young adults (30% black) aged 20-37 years. Triglyceride levels showed significant race (whiteblack) and sex (malefemale) differences. Black females, despite their relatively increased body fatness, had lowest triglyceride levels. In terms of conjoint trait of dyslipidemia based on the National Cholesterol Education Program cutpoints, 9% of white males displayed high triglyceride (or =200 mg/dl) in combination with low high-density lipoprotein (HDL)-cholesterol (35 mg/dl). In comparison, none of the black females fell into this category. Serum triglycerides even at levels between 100 and 150 mg/dl were significantly adversely associated with risk variables of insulin resistance syndrome such as adiposity and visceral fatness measures, HDL-cholesterol, insulin, and systolic blood pressure, especially among whites. Visceral fatness as measured by waist circumference (except black males) and insulin were the major predictors of triglyceride levels. Overall, triglyceride levels above 150 mg/dl were associated with increased risk of hypertension (odds ratio (OR)=1.8, 95% confidence interval (CI)=1.8-3.0), type 2 diabetes (OR=3.1, CI=1.4-6.9), parental history of hypertension (OR=1.3, CI=1.0-1.8) and parental history of type 2 diabetes (OR=1.7, CI=1.2-2.3). Thus, serum triglyceride levels may be valuable in the assessment of cardiovascular risk during young adulthood.

It is well recognized that end-stage renal disease (ESRD) is associated with accelerated and malignant hypertension. The association of renal disease and what is considered as normal blood pressure is still not clear. The present study examined the temporal relation between blood pressure and renal function reflected by serum creatinine in a biracial (black-white) community-based population enrolled in the Bogalusa Heart Study. The study included 662 young adults aged 19 to 32 years, (white men, n = 188; white women, n = 289; black men, n = 67; and black women, n = 118) who were followed for an average of 7.4 years. In black men, partial correlation adjusted for age, body mass index, serum glucose, uric acid, and cigarette smoking showed that baseline systolic and diastolic blood pressure are not significantly related to baseline serum creatinine, but significantly related to serum creatinine at follow-up (r = 0.38, P = .008 and r = 0.42, P = .003, respectively). Multivariate regression analysis further showed a significant prediction of serum creatinine at follow-up by baseline systolic and diastolic blood pressure (0.031 mg/dL and 0.037 mg/dL rise in follow-up serum creatinine for every 10 mm Hg increase in systolic (P = .000) and diastolic (P = .001) blood pressure at baseline, but not the other way around. Other race and sex groups did not show such significant temporal relations. We conclude that in young black men, higher blood pressure levels within normal range precede and explain part of the increase in serum creatinine, a measure of decline in renal function. Thus, our results underscore the beneficial effect of maintaining blood pressure levels lower than what is considered as the upper normal limit, particularly in black men.

The US Surgeon General concluded that nicotine in tobacco is addictive. Few studies actually explore the nature of nicotine addiction in youth. In Bogalusa, Louisiana, surveys to assess tobacco usage were administered to 11-18 year olds according to a standardized protocol developed in 1976. In 1991-92, a special substudy explored the nature of nicotine addiction in youth. Overall, 14.7% were current cigarette smokers; however, as many as 44.3% of white females, ages 15-16, indicated they were current smokers. Twelve percent of the surveyed population purchased single cigarettes. Thirty-two percent of current smokers reported they smoke a cigarette within 30 minutes after waking up. Thirty-one percent said they would find it difficult to refrain from smoking in places where it is forbidden. And 23% said they continue to smoke cigarettes when they are ill. From the findings in this study, it is clear there are young people who are addicted to tobacco. It is important to develop prevention of tobacco usage in childhood. Those who are addicted require a carefully developed intervention program to assist them with their cessation efforts.

To evaluate the impact of breakfast consumption patterns on the nutritional adequacy of diets of young adults and determine possible ethnic and gender differences.Cross-sectional survey of young adults in Bogalusa, La.Twenty-four-hour dietary recalls were collected from October 1988 through October 1991 on 504 young adults (mean age=23 years, 58% women, 70% white).Analysis of variance and logistic regression techniques were used to investigate the relationship of breakfast consumption, ethnicity, and gender on dietary adequacy. The P values are from an analysis of variance model that adjusted for gender and ethnicity.Thirty-seven percent of young adults skipped breakfast. Of those who ate breakfast, 75% ate at home, 10% ate a fast-food breakfast, and 15% reported other sources. Mean energy intake from breakfast was 485 kcal; men consumed more energy than women (P.001), and blacks consumed more energy than whites (P.01). The breakfast meal provided an average of 13% of energy from protein, 55% from carbohydrate, 14% from sucrose, 34% from fat, and 12% from saturated fat. Whites consumed a breakfast higher in carbohydrate and sucrose than blacks, who consumed a breakfast higher in fat and saturated fat. Variations in breakfast foods consumed explained the racial differences in the nutrient composition of the breakfast meal. Young adults who skipped breakfast had lower total daily intakes of energy (P.0001), protein per 1,000 kcal (P.05), and saturated fat per 1,000 kcal (P.01) than those who consumed breakfast. For all vitamins and minerals studied, a higher percentage of young adults who skipped breakfast did not meet two thirds of the Recommended Dietary Allowance than those who consumed a breakfast.Encouraging consumption of breakfast, along with selection of more healthful breakfast food choices or snacks that are culturally appropriate, may be important strategies for improving the nutritional quality of young adults' diets.

In adults, cardiovascular risk factors reinforce each other in their effect on cardiovascular events. However, information is scant on the relation of multiple risk factors to the extent of asymptomatic atherosclerosis in young people.We performed autopsies on 204 young persons 2 to 39 years of age, who had died from various causes, principally trauma. Data on antemortem risk factors were available for 93 of these persons, who were the focus of this study. We correlated risk factors with the extent of atherosclerosis in the aorta and coronary arteries.The extent of fatty streaks and fibrous plaques in the aorta and coronary arteries increased with age. The association between fatty streaks and fibrous plaques was much stronger in the coronary arteries (r=0.60, P0.001) than in the aorta (r=0.23, P=0.03). Among the cardiovascular risk factors, body-mass index, systolic and diastolic blood pressure, and serum concentrations of total cholesterol, triglycerides, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol, as a group, were strongly associated with the extent of lesions in the aorta and coronary arteries (canonical correlation [a measure of the association between groups of variables]: r=0.70; P0.001). In addition, cigarette smoking increased the percentage of the intimal surface involved with fibrous plaques in the aorta (1.22 percent in smokers vs. 0.12 percent in nonsmokers, P=0.02) and fatty streaks in the coronary vessels (8.27 percent vs. 2.89 percent, P=0.04). The effect of multiple risk factors on the extent of atherosclerosis was quite evident. Subjects with 0, 1, 2, and 3 or 4 risk factors had, respectively, 19.1 percent, 30.3 percent, 37.9 percent, and 35.0 percent of the intimal surface covered with fatty streaks in the aorta (P for trend=0.01). The comparable figures for the coronary arteries were 1.3 percent, 2.5 percent, 7.9 percent, and 11.0 percent, respectively, for fatty streaks (P for trend=0.01) and 0.6 percent, 0.7 percent, 2.4 percent, and 7.2 percent for collagenous fibrous plaques (P for trend=0.003).These findings indicate that as the number of cardiovascular risk factors increases, so does the severity of asymptomatic coronary and aortic atherosclerosis in young people.

To examine community differences in cardiovascular disease (CVD) risk factors among black and white young adults by combining data from two large epidemiologic studies.Data are from participants aged 20-31 years in the Coronary Artery Risk Development In Young Adults (CARDIA) study (1987-1988; N = 4129) and the Bogalusa Heart study (1988-1991; N = 1884), adjusting for data collection differences prior to analysis. CARDIA includes four urban sites: Birmingham, Alabama; Chicago, Illinois; Minneapolis, Minnesota; and Oakland, California. Bogalusa is a semi-rural town in Southeastern Louisiana. CVD risk factors examined were smoking status, body habitus, and blood pressure.In Birmingham and Bogalusa, more white than black women were current smokers; no ethnic differences were observed among men. In Chicago, Minneapolis, and Oakland, more blacks were current smokers than were whites. For all sites, educational level was strongly inversely related to current smoking status; ethnic differences were more apparent among those with up to a high school education. Among white men and women, prevalence of obesity (body mass index31.1 kg/m2 in men and 32.3 kg/m2 in women) was greater in Birmingham and Bogalusa than in Chicago. Minneapolis, and Oakland. Mean systolic blood pressures were highest in Bogalusa, and the proportion of black men with elevated blood pressure (or = 130/85 mmHg) was higher in Bogalusa and Birmingham.Community and ethnic differences in CVD risk factors were observed among young adults in two large epidemiologic studies. Further studies may enhance our understanding of the relationship of geographic differences in CVD risk to subsequent disease.

Although the association between parental coronary artery disease (CAD) and its risk factors in the offspring is known, the timing and the course of development of risk factors from childhood to adulthood in the offspring is not known.To examine the association between parental CAD and longitudinal changes in risk factor profile from childhood to young adulthood in offspring.Cohort study.Bogalusa, La, a semirural, biracial community.Individuals with clinically verified parental history of CAD (n=271) vs those without such a history (n = 1253) Mean age at first CAD event was 50 years for fathers and 52 years for mothers.Body mass index, subscapular skinfolds, blood pressure, and triglyceride, cholesterol (total, very low-density lipoprotein [VLDL-C], low-density lipoprotein [LDL-C], and high-density lipoprotein [HDL-C] cholesterols), glucose, and insulin levels.The offspring of parents with CAD were consistently overweight beginning in childhood. Their levels of total serum cholesterol, LDL-C, plasma glucose, and insulin became significantly higher at older ages, because of a higher rate of increase in these risk factors over time. In adulthood, the offspring with a positive parental history had a higher prevalence of obesity (body mass index85th percentile in the National Health and Nutrition Examination Survey I, 35% vs 26%, P=.01), elevated total cholesterol (6.2 mmol/L [240 mg/dL], 8.4% vs 4.8%, P=.05) and LDL-C levels (4.1 mmol/L [160 mg/dL], 12.4% vs 4.7%, P=.05), and hyperglycemia (glucose,6.6 mmol/L, 2.7% vs 0.4%, P.001), as well as a higher coexistence of these conditions (P=.01). Further, the prevalence of dyslipidemia, either involving only LDL-C or LDL-C in combination with HDL-C or triglycerides or both, was significantly higher in the adult offspring with parental CAD.Offspring of parents with early CAD were overweight beginning in childhood and developed an adverse cardiovascular risk factor profile at an increased rate. These observations have important implications for prevention and intervention.

To compare the body mass index (BMI) (weight/height2) and the Ponderal index (PI) (weight/height3) in childhood as predictors of adult overweight in a biracial group of children.Prospective, 15-y follow-up.835 children aged 10-15 y at baseline.Weight in kg and height in m.Overweight, defined as a BMI greater than 27 kg/m2 in young adults.Overall, the BMI and the PI at baseline were identically correlated with the BMI at follow-up (r = 0.64, p0.001). However, the predictions of overweight based on each index were distinctively affected by age, sex and race. The probability of adult overweight among 10-year old children was greater than 0.5 (50% overweight threshold) if their BMI exceeded 17 kg/m2 in black girls, 20 in white girls and 18 in boys of either race. Similarly, the 50% BMI overweight thresholds among 15-year-old children were 23 kg/m2 for black girls, 25 for white girls and 22 for boys of either race. The 50% PI overweight thresholds (in kg/m2) were 12 and 14 for 10-year-old black girls and white girls, respectively; and 14 and 16 for 15-year-old black girls and white girls, respectively. Among boys, the 50% PI threshold was 13 kg/m3 regardless of age or race.The BMI and the PI in childhood were both useful in assessing sex-and race-specific risks of adult overweight. However, assessments based on the Ponderal index were less affected by age and race than those based on the BMI, particularly among boys. Hence, to establish general weight goals for children, aimed at preventing adult obesity, the PI could be a much better choice than the BMI.

To examine the usefulness of childhood low-density lipoprotein cholesterol (LDL-C) measurement for predicting future dyslipidemia and other cardiovascular risk in adulthood.A longitudinal cohort over 15 years was identified from a community study of the natural course of arteriosclerosis: 1169 individuals (34% black), aged 5 to 14 years, were included at initial study.Levels of lipoprotein variables in childhood were associated with levels in adulthood, more strongly for total cholesterol (r = .4-.6) and LDL-C (r = .4-.6) than for high-density lipoprotein cholesterol (r = .2-.4) and triglycerides (r = .1-.4). In a stepwise multiple regression, the childhood level was most predictive of the adulthood level, followed by change in body mass index (weight in kilograms/height in meters squared) from childhood to adulthood, with explained variability (R2) of .29, .30, .27, and .19 for total cholesterol, LDL-C, high-density lipoprotein cholesterol, and triglycerides, respectively. Adulthood dyslipidemia, as defined by the National Cholesterol Education Program criterion, was best predicted by childhood LDL-C level among other lipoprotein variables. Compared with subjects with acceptable childhood risk (LDL-C level,2.84 mmol/L [110 md/dL]), those (6%) with high childhood risk (LDL-C level,or = 3.36 mmol/L [or = 130 mg/dL]) not only had a higher prevalence of dyslipidemic total cholesterol level (24%, 8.3-fold), LDL-C level (28%, 5.4-fold), triglyceride level (7%, sevenfold) and lower HDL-C level (14%, 2.1-fold), but also had a significantly higher (P.05) prevalence of obesity (43%, 1.6-fold) and hypertension (19%, 2.4-fold). In addition, if the childhood LDL-C elevation (90th percentile) was persistent, the prevalence of adult dyslipidemia would be markedly increased (P.001).Adverse levels of LDL-C in childhood persist over time, progress to adult dyslipidemia, and relate to obesity and hypertension as well. National Cholesterol Education Program guidelines to classify cardiovascular risk on the basis of LDL-C level are helpful in targeting individuals at risk early in life.

Earlier we found black-white contrast in insulin levels in adolescents. The purpose of this study is to assess whether this difference is attributable to alterations in insulin secretion and/or clearance.Fasting circulating insulin and C-peptide concentrations were examined in 1157 adolescents aged 11 to 18 years from a biracial community. Fasting plasma C-peptide, C-peptide to insulin ratio, and glucose to insulin ratio were used as indices of insulin secretion, hepatic insulin clearance, and insulin sensitivity, respectively.After adjusting several covariates (age, sexual maturation, and obesity), black adolescents had higher insulin levels (14.99 vs 12.66 microU/mL in girls). However, they had lower C-peptide levels than their white counterparts, indicating lower insulin secretion by pancreatic beta cells in black adolescents. Moreover, black adolescents had lower levels of C-peptide to insulin ratio than white adolescents (0.14 vs 0.17), suggesting reduced hepatic insulin clearance in black adolescents. In addition, significantly lower levels of glucose to insulin ratio in black girls suggest a reduced insulin sensitivity in this group. Further, differences in insulin levels between white and black girls disappeared after adjusting for differences in C-peptide to insulin ratio.These data suggest that elevated insulin levels observed in black adolescents, especially in black girls, may be attributed to their decreased hepatic insulin clearance, not hypersecretion of insulin.

RESEARCHERS RECORDED BLOOD PRESSURE LEVELS of children and adolescents in the Bogalusa Heart Study (black and white populations) and in the Brooks Country Study (Hispanic population). Hispanic children had smaller stature, while whites and Hispanics tended to be fatter than blacks in childhood. In Bogalusa, black boys showed higher blood pressure levels. Hispanic girls showed lower systolic blood pressure than the other ethnic groups. In cultures with a high prevalence of hypertension, such as blacks in the United States, it is important to understand the effect of environmental factors like dietary intake and electrolytes and obesity on the control of hypertension.

The use of fourth phase Korotkoff sound (K4) versus fifth phase Korotkoff sound (K5) for the determination of diastolic blood pressure (DBP) has been a subject of controversy since the indirect method of determining arterial blood pressure was described. Using data from the Bogalusa Heart Study, we evaluated the differences between K4 and K5 (K4-K5) from 4633 subjects 5 to 30 years of age examined between 1987 and 1991. The overall mean difference between K4 and K5 was 9.9 +/- 5.6 mm Hg (mean +/- SD). The average difference was highest in 5 to 8 year olds, where it measured 12.3 +/- 5.5 mm Hg. The average K4-K5 difference fell with increasing age and reached a value of 6.3 +/- 2.6 mm Hg by 25 years of age. For all race/sex groups, the youngest two age groups differed statistically from the oldest age groups in K4-K5 difference (P.006). There were significant differences between blacks and whites (P.015) and between men and women (P.001) for subjects between 13 and 17 years of age. Additional analyses were performed with individuals having K5 = 0 added to yield an expanded population of 5117 persons. Overall, 9.5% had at least one of six measurements of K5 = 0 and most were young subjects: 27% of children 5 to 8 years and 13% of children 9 to 12 years. We conclude that by age 15 there may be no relevant clinical difference in K4-K5. However, in children, K4 and K5 should be recorded and K4 is a more reproducible measure of diastolic blood pressure.

Age and secular trends in dietary fiber intake of children were examined using the 24-hour dietary recall method. Dietary fiber intake of five cohorts of 10-year-olds (n = 1254); two cohorts of 13-year-olds (n = 360); and children ages 10 (n = 767), 13 (n = 249), 15 (n = 108), and 17 (n = 89) years was examined from 1976 to 1988. Total dietary fiber intake remained unchanged from 1976 to 1988, even after adjusting for energy intake; averaging 12 or 5 g/100 calories (kcal). Black children had higher fiber intakes per 1000 kcal than white children from ages 10 to 17 years. Consumption of vegetables and/or soups and breads and/or cereals accounted for 53% (10 years) to 70% (13 years) of the total fiber consumed. When children were stratified into quartiles based on fiber intake per 1000 kcal, the percent of energy from total fat and saturated fat was lower, and the percent of energy from carbohydrates was higher in children with higher fiber intakes per 1000 kcal. Additional studies are needed to document dietary fiber intakes of children and their impact on overall diet composition and cardiovascular risk factors.

Two overlapping cDNA clones for core protein of a biglycan of bovine aorta were isolated from a pSPORT bovine aorta tissue cDNA library. The 2043-bp cDNA contains a 114-bp 5' untranslated region, a 1224-bp cDNA open reading frame and a 705-bp 3' untranslated region. The encoded core preproprotein contains a prepeptide (residues no. -37 to -19) and a propeptide (residues no. -18 to -1), with 369 amino acid residues corresponding to a molecular mass of 41.6 kDa. The deduced amino acid sequence revealed a striking homology to rat vascular smooth muscle cell, human bone and bovine articular cartilage biglycans from cell culture.

To document the contribution of meat consumption to the overall nutritional quality of the diet and assess its impact on cardiovascular risk factors in young adults.A cross-sectional survey of young adults in Bogalusa, La.We collected 24-hour dietary recalls from 504 19- to 28-year-olds from 1988 through 1991.We examined dietary composition by meat consumption quartiles. Analysis of variance and Newman-Keuls range tests were performed.Young adults consume an average of 6.5 oz meat daily; whites most often consumed beef and blacks most often consumed pork and poultry. Persons in the25th percentile for meat consumption consumed a diet closest to recommended levels--with 11% of energy from protein, 55% from carbohydrate, 32% from fat, 11% from saturated fatty acids, and 264 mg dietary cholesterol. In contrast, persons in the75th percentile for meat consumption consumed a diet with 18% of energy from protein, 40% from carbohydrate, 41% from fat, 13% from saturated fatty acids, and 372 mg dietary cholesterol. Intakes of heme iron and phosphorus were lower and calcium intake higher in persons in the25th percentile compared with those in the75th percentile for meat consumption. The percent of persons meeting two thirds of the Recommended Dietary Allowances for vitamin B-12, niacin, and zinc was greater in the75th percentile for meat consumption compared with the25th percentile for meat consumption. We noted no differences across meat consumption quartiles in blood lipids and lipoproteins, anthropometric measurements, and hemoglobin levels.Consumption of moderate amounts of lean meat, along with healthier choices in other food groups, may be necessary to meet the current dietary recommendations.

To determine dietary fiber intake of children and young adults.Cross-sectional surveys of children and young adults in Bogalusa, La.Twenty-four-hour dietary recalls were collected from 1976 to 1988 on five cohorts of 10-year-olds (n = 1,254), two cohorts of 13-year-olds (n = 360), and young adults (n = 504) 19 to 28 years of age.Dietary fiber intake data were analyzed for age, race, and gender differences and for secular trends. Descriptive and inferential statistics were calculated where appropriate. Dietary composition and food sources were examined for race-specific and gender-specific quartiles for dietary fiber intake adjusted per 1,000 kcal.Even after adjusting for energy intake, total dietary fiber intake remained unchanged from 1976 to 1988, averaging 12 g or 5 g/1,000 kcal. Blacks and males had higher total fiber intakes than whites and females at all ages. Consumption of vegetables and soups and breads and grains accounted for 53% (10-year-olds) to 70% (13-year-olds) of the total fiber consumed. When children were stratified into quartiles on the basis of fiber intake per 1,000 kcal, the percentage of energy from total fat and saturated fat was lower, and the percentage of energy from carbohydrate was higher, in children with higher fiber intakes per 1,000 kcal.Dietary fiber intake of children has remained the same in the past 12 years and is comparable with the intake of young adults, which is well below the recommended level. Children with high fiber intakes (upper quartile) consumed less fat, particularly saturated fat, and more carbohydrate than children with low fiber intakes. Increasing consumption of whole-grain products, fruits, vegetables, and legumes (prepared with minimal added fat) will be necessary to reach the goal of optimal fiber intake and could result in an eating pattern that approaches the current recommendations for dietary fat and saturated fat.

To assess whether circulating insulin is a major contributor to adverse lipid profiles during the transition from adolescence to young adulthood.The association between fasting insulin levels and serum lipid and lipoprotein levels was examined in a cross-sectional survey of 4136 young individuals aged 5 to 30 years from a biracial community.Fasting insulin levels were strongly and positively correlated with serum triglyceride and very-low-density lipoprotein cholesterol levels and negatively correlated with high-density lipoprotein cholesterol levels in all age groups (5 to 11, 12 to 17, 19 to 24, and 25 to 30 years). An increasing impact of insulin level on low-density lipoprotein cholesterol level was observed in young adults aged 25 to 30 years. In multivariate analysis, fasting insulin level was associated with very-low-density lipoprotein cholesterol level for most of the age groups in both races independently of age, sex, glucose levels, obesity, cigarette smoking, and alcohol intake. The independent relationship to low-density lipoprotein cholesterol level persisted in young adults aged 25 to 30 years. The independent and negative association with high-density lipoprotein cholesterol level remained in whites aged 5 to 24 years and blacks aged 19 to 24 years. When individuals were divided into tertiles according to insulin concentration and subscapular skinfold thickness, the independent effect of insulin level and obesity on lipoprotein fractions was also noted. Furthermore, a stronger association of insulin level with lipoprotein fractions was observed in obese than in lean white males.These data indicate that an increasing association of insulin levels with adverse lipoprotein levels in young adults, especially obese individuals, may have adverse consequence for adult cardiovascular diseases.

The functional properties of the apolipoproteins (apoB and apoA-I) governing lipoprotein metabolism make these variables conceptually important as markers for coronary artery disease risk. This aspect was examined in a biracial (black-white) population of children as part of the Bogalusa Heart Study. White children, especially boys, showed lower concentrations of apoA-I and ratios of cholesterol to apoB within low-density lipoprotein (LDL) than did black children. Persistence of apoB concentrations over time, coupled with its strong linkage with apoB gene locus, underscores the value of detecting apoB excess early in life. Further, the impact of apoE genotypes on apoB and apoA-I levels is already evident in childhood. We found that, as a screening test for detecting increased LDL cholesterol, apoB is superior to total cholesterol. Low values for apoA-I concentration, the apoA-I to apoB ratio, and LDL cholesterol to apoB ratio in children are strongly related to parental incidence of myocardial infarction; no such relationship is seen with respect to lipoprotein cholesterols. Thus, expanding screening strategies might be useful for identifying individuals with adverse apolipoprotein profiles early in life.

The association between microalbuminuria and blood pressure levels was examined in young white and black adults (n = 1131) aged 19 to 32 years. Urinary ratio of albumin (mg/L) to creatinine (mmol/L) was used as an estimation of urinary albumin excretion. Black men and women compared with their white counterparts had higher levels of blood pressure. Significantly positive correlations between urinary albumin excretion and systolic and diastolic blood pressures were observed in black men (r = 0.20 and r = 0.24, P.01) and black women (r = 0.15 and r = 0.14, P.05). Similar correlations of significance were not seen in the white counterparts. Systolic and diastolic blood pressure levels were significantly higher in normotensive black subjects (140/90 mm Hg) with increased urinary albumin excretion (or = 90th percentile) than in those without increased urinary albumin excretion. After accounting for potential confounding by age, sex, and body mass index, blacks in the uppermost systolic and diastolic blood pressure group were 7.1 times (95% CI, 2.0 to 25.8) and 4.8 times (1.3 to 18.3), respectively, as likely to have elevated albumin/creatinine excretion as those in the lowest group. In contrast, the likelihood for elevated albumin/creatinine excretion were 0.9 times (95% CI, 0.5 to 2.2) and 1.1 times (0.5 to 2.3), respectively, in whites, which were not significant. These data suggest that a stronger association between blood pressure levels and urinary albumin excretion exists in young blacks than in whites, which supports the notion that blacks may be more susceptible to renal damage from relatively low levels of blood pressure increases.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiovascular risk factors are known to persist over time and to cluster both in childhood and adulthood. Less is known about the persistence of clustering of multiple cardiovascular risk factors comprising adverse levels of systolic blood pressure, the ratio of total cholesterol to high-density lipoprotein cholesterol, and plasma insulin from childhood to young adulthood.In a community study of cardiovascular risk, 1176 individuals (52% female, 44% black) aged 5 through 17 years at baseline were followed up for 8 years.Calculated as sum of the race-, sex-, and age-specific rankings of systolic blood pressure, insulin level, and total to high-density lipoprotein cholesterol ratio, the multiple risk index was shown to track in all four race-sex groups (year 1 vs year 8 correlations, .54 to .67). The magnitude of the overall multiple risk index tracking correlation (r = .64) was significantly stronger than that noted for individual risk factors (r = .34 to .57). Among subjects who were initially in the highest quintile of the multiple risk index, 61% remained there 8 years later. Tracking of the multiple risk index increased progressively with age and ponderal index (weight/[height3]). In a step-wise regression analysis, baseline multiple risk index score, baseline ponderal index, change in ponderal index, and change in height were predictive of the multiple risk index score on follow-up. These predictors explained 45% to 60% of the variability in multiple risk index scores among the race-sex groups.The persistence of multiple cardiovascular risk clustering from childhood to adulthood and the impact of obesity in this regard point to the need for preventive measures aimed at developing healthy lifestyles early in life.

Epidemiological studies of BPs in children and young adults over the past 20 years have contributed considerably to understanding the early onset of primary hypertension. Observations from autopsies and echocardiographic studies, together with long-term BP studies, of children clearly indicate that primary hypertension begins in early childhood. Although abnormal BP levels in children are much lower than the adult criteria used for clinical diagnosis of hypertension, essential hypertension is identifiable in early life. Complex haemodynamic and metabolic mechanisms related to essential hypertension are also being identified in childhood. The development of intervention programs in an attempt to prevent hypertension in its early phases suggests hypertensive cardiovascular disease is preventable. Environmental factors (improved dietary factors, altering electrolyte intake, prevention of obesity and increased activity levels) are critical elements to prevention. Children and young adults identified as high risk for hypertension need to be targeted for prevention of early cardiovascular renal disease. Also, as hypertension is so prevalent, attempts should be made to control environmental factors in the general public. Preventive programmes established by primary healthcare physicians, paediatricians and para-professionals can have a major impact on the reduction of hypertension and its complications of cardiovascular renal disease in the future.

Maximum likelihood linkage analyses were performed to test for linkage between serum apoB levels and several candidate gene markers including apolipoprotein B, lipoprotein lipase, hepatic lipase, cholesterol ester transfer protein, and apolipoprotein AI in a large pedigree. Parameters of general Mendelian inheritance derived from maximum likelihood segregation analysis of the serum apoB levels were used in the linkage analysis. The highest two-point lod score between the quantitative trait and a marker defined by a single restriction digest was 1.86 at recombination fraction (theta) = 0. This was observed for linkage between serum apoB levels and the presence or absence of a PvuII digestion site in the apoB gene. Linkage between serum apoB levels and polymorphisms of the apoB gene defined by the two restriction digests EcoR1 and PvuII was supported by a lod score of 3.30, while inclusion of VNTR typings led to a lod score of 2.33. None of the other candidate genes gave positive evidence of linkage.

Dietary intake of military wives and factors that influence nutrition of military families were examined in 186 military wives--67% white, 18% black, 11% Hispanic, and 4% other. The ages ranged from 19 to 45 years (mean = 28.7 years). The observations show that 1.7 meals per day were shared by all family members. Due to differences in energy intake and RDAs by age, dietary intakes were assessed in two age groups: 19-24 years (N = 51) and 25-45 years (N = 135). For both age groups, total energy intakes were lower than the RDAs, and the dietary composition was 52% carbohydrate (CHO), 14% protein, and 34% fat. Military wives 25-45 years old consumed more CHO in the form of sugar compared to the younger wives, who consumed more CHO in the form of starch. Some families require food stamps and are in the WIC program. There were no age differences in the type of protein or fat consumed, averaging 66% animal protein and 12% saturated fat. Dietary cholesterol intake was 229 mg for wives 19-24 and 243 mg for older wives and, based on approximately 1,900 kcal, dietary cholesterol exceeded 100 mg/1,000 kcal in both age groups. Sodium intake averaged 3.2 g. Forty-five percent of the military wives did not meet two-thirds of the RDA for vitamins D, E, B-6, iron, folic acid, zinc, and magnesium. Less than 20% met two-thirds of the RDA for riboflavin, vitamin A, thiamin, iodine, selenium, and calcium.(ABSTRACT TRUNCATED AT 250 WORDS)

This paper introduces three cardiovascular health evaluation and promotion projects targeting military families at Fort Polk, Louisiana. These studies examine dietary behavior and life-styles including tobacco and alcohol use of military wives, physical activity, cardiovascular disease risk factors of military personnel and their families, and other behavioral profiles with the goal of developing a healthy lifestyle modification program for families. Relevant biomedical background and rationale considerations are developed to support the current research. In addition, conclusions drawn from these studies indicate the opportunity for future health promotion programs at other military installations. The studies will provide the background for a manual of operations to conduct health promotions for families on a military base. Further, the model provides the opportunity for a social support mechanism for families during times of stress and military operations.

In order to identify potential abnormalities, a cardiovascular risk-factor screening was developed as part of the Fort Polk Heart Smart Program. Serum lipids and lipoproteins, blood pressure, and selected anthropometric indices were measured on 703 individuals. Overweight was more a problem for females, with over 40% having a body mass index greater than 27. The percentage of subjects exceeding National Cholesterol Education Program guidelines increased with age. Some 30% of white men 30-39 years old and 60% of white men above 40 years old had elevated total cholesterol. These observations provide the basis for a health promotion program for young military families.

Lifestyles are major determinants in development of heart disease. Tobacco and alcohol use, physical activity, and hostility, a component of type A, were assessed in a sample of active military men and their wives at Fort Polk, Louisiana. Findings included: (1) a greater frequency of cigarette smoking at Fort Polk compared to national surveys; (2) a higher frequency of alcohol consumption in ages 30-39, and more blacks reported alcohol use than other race groups; (3) a greater frequency of alcohol use at Fort Polk compared to a worldwide military survey; (4) no consistent differences in lipid or blood pressure levels for high and low activity groups of wives; and (5) wives' hostility scores were low, and were not correlated with other cardiovascular risk factors. The implication of lifestyle descriptions is the need for intervention and health promotion, not only for military personnel, but also for their families. The significance of health promotion programs is the eventual reduction of health care costs and the well-being of families and fitness of military personnel.

Serum lipid and lipoprotein distributions and their correlates were examined in white, black, and Hispanic Army personnel and their families (N = 589) as part of the Fort Polk Heart Smart Program. In general, blacks tended to have higher HDL-C and lower triglycerides and VLDL-C than whites and Hispanics, whereas Hispanics tended to manifest higher triglycerides, VLDL-C, and LDL-C than whites. Unlike black and Hispanic men, white men tended to have lower HDL-C than white women. In contrast to white men, both black and Hispanic men displayed elevated LDL-C compared with black and Hispanic women. A considerable proportion of individuals tended to manifest adverse lipoprotein patterns according to National Cholesterol Education Program guidelines for children and adults. Cigarette smoking and alcohol use were the major contributors to the variance of lipoproteins in men, whereas overweight and oral contraceptive use remained the major factors in this regard for women. These results indicate that early targeting of military personnel and their family members for primary prevention is highly desirable.

The relationship between fasting plasma insulin and blood pressure was studied in a cross-sectional survey of children and young adults aged 5 to 26 years.Fasting plasma insulin, glucose, blood pressure, and anthropometric measurements were obtained on 3518 individuals.When divided into four age groups, the analyses showed that fasting insulin was significantly and positively correlated to both systolic and diastolic blood pressure in individuals at all age groups, except at 13 to 17 years. In multivariate regression analyses, fasting insulin remained independently associated with blood pressure levels after controlling for glucose levels, body mass index (weight/height) and skinfold thickness in children (aged 5 to 12 years) and young adults (aged 18 to 26 years), although not in adolescents (aged 13 to 17 years). Moreover, fasting insulin was more strongly related to systolic than to diastolic blood pressure. The fasting blood glucose level did not contribute independently to multivariate prediction of blood pressure in young adults. When the children and young adults were divided into tertiles according to fasting insulin and body mass index, the independent effect of insulin and body mass index on systolic pressure was also seen in children and young adults.The association between plasma insulin and blood pressure noted even in healthy children and young adults help target areas for cardiovascular risk prevention.

To investigate sex differences in the evolution of the QT interval with age.A community-based representative North American population sample of 14,379 children and adults aged from birth to 75 years. The measured QT intervals (QTm) were determined by a computer algorithm and QTm, corrected for heart rate (HR), was expressed as QT index: QTI = (QTm/Tp) x 100, where QTp is the predicted QT from the formula QTp (ms) = 656/(1 + HR/100).The QTI values of females were significantly longer than of males in all age groups from 15 to 50 years tested at yearly intervals. This difference was due to a 20 ms drop in rate-corrected QT values in adolescent males after puberty, whereas QT values of females remained unchanged throughout the growth, maturation and reproductive years. The new QT prediction formula explained 83% of total QT variance in females and 82% in males after adjustment for heart rate and for the observed significant influence of ventricular excitation time (QRS duration) on QT interval in both sexes and a correction for QT age trend in males.The sex difference in the QT interval is due to QT shortening in males after puberty rather than QT prolongation in women during reproductive years. The fact that QRS duration is a significant determinant of the QT interval has important theoretical implications for attempts to model the ventricular repolarization process and it indicates that the traditional concept of reverse sequence of ventricular repolarization is not universally valid in all myocardial regions.

Various electrolytes and energy intakes have been shown to contribute to the risk of hypertension and other cardiovascular diseases. Further, dietary sodium (Na) and potassium (K) balance are important in both nonpharmacologic and pharmacologic management of various cardiovascular states. Emphasis is also given to weight reduction and electrolyte balance. As an aid to food selection to enhance K intake and decrease Na intake, we have categorized foods according to their electrolyte density as related to caloric content. More than 100 individual food items were assigned to one of four categories. Ratios of individual Na, K, and energy content were calculated, based on USDA-generated food nutrient values. Category 1 includes foods that are low in Na, high in K and low in energy: fresh or frozen vegetable sources with vitamins A and C. Category 2 contains foods low in Na relative to high K and high energy: most fruit, starchy vegetables, nuts, milk and meat products, and chocolate. Category 3 includes foods high in Na that are also high in K in relation to low energy: vegetables (canned, frozen in butter sauce or au gratin), most cheeses, cured or frozen meats. Category 4 contains foods high in Na and low in K relative to high energy: bread, rice, luncheon meats, commercial cookies and pastries, and fast food entrees. Commercial cereals could be differentiated by the guidelines, with bran cereals in Category 1, shredded wheat products in Category 2, fruit-containing cereals in Category 3, and presweetened or instant cereals in Category 4. Identification of the ratio of Na and K to content of foods, compared with relative energy ratio, is useful in selecting foods that will help meet specific dietary criteria for management of essential hypertension and other cardiovascular-renal states, both in the adult and pediatric populations.

A self-administered food frequency questionnaire (FFQ) was developed to indicate weekly consumption of 64 foods. Reliability, validity, and usefulness of the tool to define a protein eating pattern were determined. Adolescents (N = 1,108) completed the FFQ during the Bogalusa Heart Study. Two-hour and 2-week reliability measures demonstrated consistency of intake of specific foods. Frequency of foods obtained from seven consecutive 24-hour recalls was compared with frequency obtained from the FFQ. A mean 50% agreement for both frequency and quantity of food intake was observed. Geometric means showed differences in mean number of protein foods by age of adolescent but the only significant difference was for beef intake of 15-year-olds. White children reported more servings of beef, cheese, and vegetables with meat than did black children. Black children reported more servings of eggs, luncheon meat, pork, poultry, and total protein than did white children. Boys reported a greater frequency of total protein foods, specifically, eggs, milk, and poultry, than did girls. Significant correlations were noted between low-density-lipoprotein cholesterol and intake of eggs and luncheon meat. We were able to quantitate the reliability and validity of the FFQ and to use it to explore the association of specific eating patterns with cardiovascular disease risk.

Nutritional adequacy is important when diets and dietary alterations are recommended for children. Concern is expressed that low fat intakes may have deleterious effects on growth and development and may be deficient in total calories and essential nutrients. In a study of the effect of variation in percent fat in the diet, a sample of 871 ten-year-olds was stratified according to four different fat intakes: less than 30% of total kilocalories (kcal), 30% to 35% kcal, 35% to 40% kcal, and greater than 40% kcal. The race/sex distribution was similar within each fat intake group. Fourteen percent of the sample had fat intakes less than 30% of total calories. The amount of calories from breakfast, dinner, and snacks was higher in the children with fat intakes greater than 40% of total calories than those with lower fat intakes. The energy intake of all race/sex groups fell within the recommended range. The low fat intake group was eating 25% less calories than the high fat intake group (1800 kcal vs 2400 kcal). The percentage of calories from carbohydrate, specifically sugar, was greater in the low fat intake group compared with the high fat intake group. Percentage of calories from protein was approximately 13% for all groups. Fiber and starch were the same across all fat intakes.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiovascular diseases, atherosclerosis and essential hypertension, are the major causes of morbidity and death in the United States today. Research over the past 20 years now clearly establishes that both diseases begin in childhood (1,2). Understanding the early natural history of coronary artery disease is tremendously important as it progresses to a clinical horizon later in life. It is equally important to begin considerations on intervention in early life to prevent adult coronary artery disease and hypertensive disease (3). Observations made in the Bogalusa Heart Study and other epidemiologic programs on children now provide a wealth of data on cardiovascular risk factor variables as they occur in various developmental periods of life — infancy, childhood, adolescence and young adulthood.

Obesity is an important determinant of serum lipids and lipoproteins in adults. Since obesity begins early in life, the impact of obesity of serum lipid and lipoprotein levels was examined in 3311 children and young adults (ages 5 to 26 years) from a totally biracial community. Study subjects were grouped according to race, sex, and age categories (5 to 10 years, 11 to 16 years, 17 to 22 years, and 23 to 26 years), excluding females using oral contraceptives or who were pregnant. Overall, associations increase with age, being most prominently noted in white males. The strong positive relation of ponderosity to low-density lipoprotein cholesterol was indicated in the older age groups with correlation coefficients ranging from r = -.09 in the youngest black males to r = .47 in white males aged 17 to 22 years. A negative association was noted between ponderosity and high-density lipoprotein cholesterol with correlation coefficients ranging from r = .08 in black females aged 17 to 22 years to r = -.39 in the oldest white males. Similar results were seen using subscapular skin-fold thickness as a measure of central obesity. Overweight was defined as exceeding 20% above the National Health Anthropometric and Nutritional Examination Survey II survey 50th percentiles. The prevalence of overweight individuals increased with age, being most prominent in black females. The percent(s) of hypercholesterolemic cases, based on the National Cholesterol Education Program criteria, likewise increased with age. A marked proportion of older white males were classified as borderline high and high for low-density lipoprotein cholesterol. A regression model using subscapular skinfold to predict serum lipids and lipoproteins within each age group indicated a consistent increase in the adverse nature of the lipid profile. Intervention and education programs aimed at reducing obesity at younger ages are recommended to reduce serum lipid and lipoprotein levels developing in young adulthood.

The distribution of serum uric acid and its relationship with cardiovascular risk variables have been studied in 3983 children and young adults, aged 5 to 26 years, drawn from a biracial (black and white) population. For two age groups, 5 to 11 years and 19 to 26 years, white subjects had significantly higher uric acid levels than black subjects, (4.02 mg/dl vs 3.57 mg/dl, p less than 0.0001, and 5.50 mg/dl vs 5.18 mg/dl, p less than 0.0001, respectively). Men in the 19 to 26 years age group had a significantly higher uric acid level than women (6.49 mg/dl vs 4.20 mg/dl, p less than 0.0001). White children and young adults were twice as likely to have levels above clinical limits than blacks, and males more likely to have hyperuricemia than females. Parents with a history of myocardial infarction were more likely to have children with hyperuricemia. Children and young adults with hyperuricemia had significantly higher plasma glucose (p less than 0.01) and insulin (p less than 0.001) levels, total cholesterol level (p less than 0.05), and serum triglyceride (p less than 0.0001), very-low-density lipoprotein cholesterol (p less than 0.01), low-density lipoprotein cholesterol (p less than 0.001), and total protein (p less than 0.0001) levels than subjects without hyperuricemia; high-density lipoprotein cholesterol level was significantly lower (p less than 0.0001) in subjects with hyperuricemia than in those without it.(ABSTRACT TRUNCATED AT 250 WORDS)

Between the years 1979 and 1981, Louisiana ranked 7th in average annual coronary heart disease (CHD) death rate among white women and 6th among black women, age 35 to 74 years. Nationally, death in women due to CHD is 250,000 deaths per year, mainly in women over 50 years of age. That is approximately one half of all deaths due to heart disease in the United States. Risk factors for CHD in women are those which are shared with men, eg, smoking, hypertension, plasma lipoprotein concentrations, obesity, diabetes, and family history, and those which apply solely to women, eg, contraceptive use, menopause, and postmenopausal hormones. The purpose of this manuscript is to review current knowledge regarding CHD in women.

Serum lipids (total cholesterol and triglycerides) and lipoprotein cholesterol fractions (low density lipoprotein (LDL) cholesterol, very low density lipoprotein (VLDL) cholesterol, and high density lipoprotein (HDL) cholesterol) have been measured approximately every 3 years on children and young adults since 1973-1974 in Bogalusa, Louisiana, a community of approximately 22,000 individuals, one-third of whom are black and two-thirds of whom are white. A total of 1,586 children were examined both at baseline (1973-1974) and at the most recent survey (1984-1986), providing 12 years of follow-up. The decreases in levels noted during puberty for total cholesterol and LDL cholesterol, primarily for boys, were followed by a rise until age 26 years. HDL cholesterol levels, particularly for white boys, continued to drop after age 14 years, yielding increasingly high LDL cholesterol/HDL cholesterol ratios. Tracking, as measured by both correlation coefficients and persistence at extreme quartiles, was evident for all of the lipids and lipoproteins. The 12-year correlation coefficients were greatest for LDL cholesterol and no trend in the magnitude of the correlation coefficients with age was noted. Tracking for HDL cholesterol was better after age 9 years, particularly for white males. Approximately 50% of those children who had total cholesterol levels or LDL cholesterol levels above the 75th percentile at baseline remained elevated 12 years later. For HDL cholesterol, a trend with age was noted for white boys: 42% of those aged 9-14 years in the lower most quartile persisted in this rank 12 years later. The best predictor of follow-up lipid or lipoprotein level was baseline level. The next best predictor was increase in weight as defined by weight/height, an index of obesity. That serum lipid and lipoprotein levels continue to track from childhood into young adulthood points to the necessity of measurement early in life and, where indicated, the introduction of preventive and interventional programs aimed at developing healthy lifestyles.

The arterial wall proteoglycans play a crucial role in the pathogenesis of atherosclerosis as depicted schematically in Figure 7. Plasma components including lipoproteins cross the endothelium mainly by a non-specific bulk-phase vesicular transport. A selective interaction of apoB-containing lipoproteins occurs with proteoglycans of the subendothelial layer which results in extracellular retention and accumulation of lipoproteins. Such interaction alters the structural and charge characteristics of LDL particles. These altered LDL are taken up by monocyte-derived macrophages by scavenger receptor-mediated endocytosis, leading to cholesteryl ester accumulation and foam cell formation. Further, retention of LDL by proteoglycans in the extracellular matrix also increases the chances of oxidative modification of lipoproteins. All of these changes may be occurring at a marginal level as a normal adaptive process of the arterial wall. However, focal response to chronic hemodynamic stress, hyperlipidemia or other forms of injury may functionally alter the endothelium, and cause greater influx of lipoproteins and smooth muscle cell proliferation, resulting in increased synthesis of proteoglycans with altered characteristics. Enhanced binding of apo-B containing lipoproteins to proteoglycans under these conditions sets the stage for the development of athersclerosis.