Search

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.

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.

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.

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.

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.