Serum lipids and apolipoproteins in Spanish children and adolescents: a 5 year follow-up

Tracking of serum lipid levels from childhood to adulthood: Systematic review and meta-analysis

BACKGROUND AND AIMS

The utility of lipid screening in pediatric settings for preventing adult atherosclerotic cardiovascular diseases partly depends on the lifelong tracking of lipid levels. This systematic review aimed to quantify the tracking of lipid levels from childhood and adolescence to adulthood.

METHODS

We systematically searched MEDLINE, Embase, Web of Science, and Google Scholar in March 2022. The protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO; ID: CRD42020208859). We included cohort studies that measured tracking of lipids from childhood or adolescence (<18 years) to adulthood (≥18) with correlation or tracking coefficients. We estimated pooled correlation and tracking coefficients using random-effects meta-analysis. Risk of bias was assessed with a review-specific tool.

RESULTS

Thirty-three studies of 19 cohorts (11,020 participants) were included. The degree of tracking from childhood and adolescence to adulthood differed among lipids. Tracking was observed for low-density lipoprotein cholesterol (pooled r = 0.55-0.65), total cholesterol (pooled r = 0.51-0.65), high-density lipoprotein cholesterol (pooled r = 0.46-0.57), and triglycerides (pooled r = 0.32-0.40). Only one study included tracking of non-high-density lipoprotein cholesterol (r = 0.42-0.59). Substantial heterogeneity was observed. Study risk of bias was moderate, mostly due to insufficient reporting and singular measurements at baseline and follow-up.

CONCLUSIONS

Early-life lipid measurements are important for predicting adult levels. However, further research is needed to understand the tracking of non-high-density lipoprotein cholesterol and the stability of risk classification over time, which may further inform pediatric lipid screening and assessment strategies.

Tracking of apolipoprotein B levels measured in childhood and adolescence: systematic review and meta-analysis

To quantify the tracking of apolipoprotein B (apoB) levels from childhood and adolescence and compare the tracking of apoB with low-density lipoprotein (LDL) cholesterol, a systematic search of MEDLINE, Embase, Web of Science, and Google Scholar was performed in October 2023 (PROSPERO protocol: CRD42022298663). Cohort studies that measured tracking of apoB from childhood/adolescence (< 19 years) with a minimum follow-up of 1 year, using tracking estimates such as correlation coefficients or tracking coefficients, were eligible. Pooled correlations were estimated using random-effects meta-analysis. Risk of bias was assessed with a review-specific tool. Ten studies of eight unique cohorts involving 4677 participants met the inclusion criteria. Tracking of apoB was observed (pooled r = 0.63; 95% confidence interval [CI] = 0.53-0.71; I2 = 96%) with no significant sources of heterogeneity identified. Data from five cohorts with tracking data for both lipids showed the degree of tracking was similar for apoB (pooled r = 0.59; 95% CI = 0.55-0.63) and LDL cholesterol (pooled r = 0.58; 95% CI = 0.47-0.68). Study risk of bias was moderate, mostly due to attrition and insufficient reporting.

CONCLUSION

ApoB levels track strongly from childhood, but do not surpass LDL cholesterol in this regard. While there is strong evidence that apoB is more effective at predicting ASCVD risk than LDL cholesterol in adults, there is currently insufficient evidence to support its increased utility in pediatric settings. This also applies to tracking data, where more comprehensive data are required.

WHAT IS KNOWN

• Apolipoprotein B is a known cause of atherosclerotic cardiovascular disease. • Apolipoprotein B levels are not typically measured in pediatric settings, where low-density lipoprotein cholesterol remains the primary lipid screening measure.

WHAT IS NEW

• This meta-analysis of 10 studies showed apolipoprotein B levels tracked strongly from childhood but did not exceed low-density lipoprotein cholesterol in this regard. • More comprehensive tracking data are needed to provide sufficient evidence for increased utility of apolipoprotein B in pediatric settings.

Association of lipid profile and waist circumference as cardiovascular risk factors for overweight and obesity among school children in Qatar

BACKGROUND

Childhood obesity is a national as well as worldwide problem. The aim of this study was to evaluate the association of overweight and obesity among Qatari children with lipid profile and waist circumference as adverse cardiovascular risk factors in children aged 6-11 years. International Obesity Task Force reference values were used to screen for overweight and obesity.

METHODS

A cross-sectional study in a randomly selected sample was conducted in 315 Qatari primary school students aged 6-11 years. Anthropometric measurements, including body weight, height, waist circumference, and body mass index were calculated for 151 girls and 164 boys. Weight categories were based on International Obesity Task Force reference values. Fasting blood glucose, total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides were measured, and atherogenic index was calculated.

RESULTS

In total, 31.71% of boys and 32.78% of girls were overweight or obese. Overweight and obese children screened against International Obesity Task Force reference values had a significantly increased risk of high waist circumference (P < 0.0001), hypertriglyceridemia (P = 0.002), low HDL-C (P = 0.017), and atherogenic index (P = 0.021) compared with children who were not overweight or obese. The partial correlation coefficient for the cardiovascular risk marker of waist circumference indicated a positive significant association with total cholesterol (r = 0.465, P = 0.003), triglycerides (r = 0.563, P < 0.001), and LDL-C (r = 0.267, P = 0.003), and a significant negative association with HDL-C (r = -0.361, P = 0.004). Overweight and obesity significantly increase the odds ratios (ORs) and 95% confidence interval (CIs) of cardiovascular risk factors as follows: hypertriglyceridemia (OR 6.34, CI 2.49-13.44, P < 0.0001); LDL-C (OR 3.18, CI 1.04-9.75, P = 0.043); hypercholesterolemia (OR 1.88, CI 1.10-3.19, P = 0.020); and increased waist circumference (OR 1.40, CI 1.29-1.55, P = 0.022). Overweight and obesity significantly increased the risk of atherosclerosis (assessed by atherogenic index) by about two-fold (OR 1.83, 95% CI 1.06-3.15, P = 0.025).

CONCLUSION

Overweight and obese children screened by International Obesity Task Force reference values are at increased risk of cardiovascular disease in adulthood.

Changes and variability in high levels of low-density lipoprotein cholesterol among children

OBJECTIVE

A 2008 report from the American Academy of Pediatrics recommended both population and individual approaches (including pharmacologic interventions) for adolescents who had low-density lipoprotein (LDL) cholesterol levels above various cutoff points (130, 160, and 190 mg/dL). However, the tracking and variability of these very high levels have not been investigated.

METHODS

A total of 6827 subjects underwent multiple LDL cholesterol determinations in childhood and adulthood in the Bogalusa Heart Study. The total number of determinations was 26748, and the median interval between examinations was 3 years.

RESULTS

Correlations between initial and subsequent LDL cholesterol levels ranged from r approximately 0.8 for measurements made within the same year to r approximately 0.5 for periods of > or = 20 years. Most children who had very high LDL cholesterol levels, however, had substantially lower levels at the next examination. LDL cholesterol levels between 160 and 189 mg/dL (n = 201) decreased, on average, by 21 mg/dL at the next examination, whereas levels of > or = 190 mg/dL (n = 44) decreased by 34 mg/dL. In contrast, the mean increase for LDL cholesterol levels of <70 mg/dL was 13 mg/dL. These changes were equal to those expected on the basis of regression to the mean.

CONCLUSIONS

There can be large changes in extreme levels of LDL cholesterol because of regression to the mean, and practitioners should be aware that very high levels may decrease substantially in the absence of any intervention.

Serum lipid and apolipoprotein profiles in newborns and six‐year‐old children: The Tallinn Young Family Study

Seventy children aged 6 years (34 boys, 36 girls) were studied for cardiovascular risk factors. Among the children 40 had also been investigated at birth. The aim of the study was to determine changes in serum lipoprotein parameters from birth up to preschool age and to assess the role of some relevant factors that might affect the process. An obvious association was found between serum apolipoprotein (apo) B levels, the apoB/apoA-I ratio and lipoprotein(a) (Lp(a)) levels at birth and at 6 years of age (r = 0.43; p<0.05, r = 0.73; p<0.0001 and r = 0.81; p<0.0001, respectively). Thirty percent of children who were in the top quartile by apoB or total cholesterol levels and 66.7% of those in this quartile by apoB/apoA-I ratio at birth remained in the top quartiles also in the follow-up study. The significantly higher apoB/apoA-I ratio in newborns and the apoB/apoA-I and apoB values in the 6-year-old children were observed in the carrier apoE4 isoform as compared to E3 homozygotes. A significant influence of apoE polymorphism on serum apoB/apoA-I ratio and apoB level in preschool children was confirmed by ANOVA one-way analysis of variance. In a multiple regression analysis from all the studied factors, the independent determinants of apoB level in preschool age were apoE phenotype, gestational age and Apgar score in the first minute of life. Thus, tracking of serum Lp(a), apoB, apoB/apoA-I ratio and total cholesterol levels from birth up to 6 years of age was demonstrated. The association between apoE polymorphism and serum lipoprotein parameters became more obvious after the first 6 years of life.

[Five-year follow up of lipid profile in children in the Rivas-Vaciamadrid study]

OBJECTIVE

To evaluate lipid balance in children after a 5-year follow-up and tracking between initial and final levels.

METHODS

Two hundred eighty-one children included in the Rivas-Vaciamadrid study were evaluated at the ages of 6 and 11 years. In all children, total cholesterol (TC), triglycerides (TG), high-density lipoprotein-cholesterol (HDL-C), and apoproteins A1 (Apo A) and B100 (Apo B) were measured. Low-density lipoprotein-cholesterol (LDL-C) was determined and the Apo B/Apo A, TC/HDL-C, and LDL-C/HDL-C ratios and the atherogenic index were calculated.

RESULTS

At 11 years of age, lipid balance was worse in girls than in boys. Levels of TG and HDL-C were significantly higher at the age of 11 years than those at the age of 6 years, but levels of the remaining variables analyzed were lower, except for Apo A and TC, which showed a non-significant increase. The correlation coefficients between values at the ages of 6 and 11 years were significant for all variables and the highest was LDL-C in girls (0.711). Kappa and Nishio tracking indexes were significant for all variables and were highest for the atherogenic index (0.431 and 6.71 respectively) and lowest for TG (0.129 and 2.85 respectively). Subjects in the highest quartile at 6 years old had a relative risk of 8.04 (CI 4.34-14.88) for having the same atherogenic index at the age of 11 years and a relative risk of 1.91 (CI 1.05-3.46) for having the same TG value.

CONCLUSION

There is a significant correlation between lipid profile values in children at the ages of 6 and 11 years. The best tracking was found in the atherogenic index.

Fat content of the diet among preschool children in southwest Britain: II. relationship with growth, blood lipids, and iron status

OBJECTIVE

In most countries, it is recommended that adults restrict fat intake to 30% to 35% of energy to reduce the risk of coronary heart disease and certain cancers. However, the appropriate level of fat in the diet of children is hotly debated. It has been generally accepted that fat intake by children under 2 years of age should not be limited because of fears that nutrient intakes and thus growth and iron status might be compromised. However, there is very little longitudinal information on the relationship between fat intake and growth in representative populations of free-living children under 2 years old. The objective of this study was to investigate the relationship between fat intake as a percentage of energy, and nutrient adequacy, growth, blood lipids, and iron status in 18- and 43-month-old children.

DESIGN

This study forms part of the Avon Longitudinal Study of Parents and Children (ALSPAC)-a geographically-based cohort study in southwest England. A randomly selected subsample of the ALSPAC cohort attended research clinics approximately every 6 months from birth, at which a variety of anthropometric and other measurements were made. Dietary intakes at 18 and 43 months were assessed using a 3-day unweighed food record. A capillary blood sample was taken at 18 months for measurement of hemoglobin and ferritin levels. Nonfasting venous blood samples were taken at 31 and 43 months and analyzed for total and high-density lipoprotein cholesterol. The children were divided into quartiles of fat intake as a percentage of energy (QFI). QFI groups were compared for the number of children reaching recommended nutrient intakes, and for anthropometry, measures of iron status, and blood lipid levels.

PARTICIPANTS

Nine hundred fifty-one children at 18 months and 805 children at 43 months.

RESULTS

The mean (standard deviation) percentages of energy from fat in each quartile at 18 months were 31.2 (2.8), 36.1 (0.9), 39.1 (0.8), and 43.1 (2.2), corresponding to a fat intake in grams of 37.3 (8.1), 44.3 (8.1), 50.4 (10.2), and 55.4 (12.7). The number of children failing to reach recommended intake levels for zinc and vitamin A fell with increasing fat intake, while the number of children consuming less than the recommendations for iron and vitamin C rose at both ages. Despite this, there was no association between fat intake at 18 months and mean height or body mass index (BMI) at either 18 or 31 months. Fat intake at 43 months was also unassociated with concurrent or subsequent height or BMI. There was also no significant increase in the number of children falling below the tenth percentile for height or BMI as QFI fell. Mean ferritin levels at 18 months fell in both sexes as QFI increased. Total cholesterol levels at 31 months were significantly associated with QFI at 18 months, and rose from 3.99 mmol/l in the lowest QFI in boys, to 4.31 mmol/l in the highest QFI. QFI at 43 months was unassociated with cholesterol levels.

CONCLUSIONS

These data do not suggest that fat intakes are an important determinant of growth in these children, even before the age of 2 years, or that children at the bottom of the range of fat intakes are experiencing delayed growth. On the other hand, there is also no evidence in this study that children on higher fat intakes are at a greater risk of becoming obese. In contrast to a number of US studies, we have not found children on lower fat intakes to have lower iron intakes-indeed higher fat intakes were associated with a greater chance of consuming less than the recommended intake of iron and with lower ferritin levels. The association of higher fat intakes with higher total cholesterol levels among boys is of concern, as there is evidence that the process of atherosclerosis begins during the preschool years.

Apolipoprotein screening in Australian children: feasibility and the effect of age, sex, and ethnicity

OBJECTIVE

(i) To evaluate the feasibility of detecting adverse lipid profiles in schoolchildren by measuring capillary dried blood spot apolipoprotein levels, and (ii) to assess the effect of age, sex and ethnicity on apolipoprotein levels.

DESIGN

We measured capillary dried blood spot apolipoproteins B and A-I (apo B and apo A-I); assessed levels in relation to age, sex and ethnicity; and recalled children with elevated levels for a full lipid profile measurement.

PARTICIPANTS AND SETTING

6992 children (3501 boys and 3491 girls), aged 5-13 years, from schools in eastern Sydney, 1991-1995.

MAIN OUTCOME MEASURES

Capillary blood levels of apolipoproteins B and A-I, and serum total cholesterol level.

RESULTS

Of the 6951 children who provided an adequate fingerprick blood sample, we recalled 1465 children (21.1%) (640 boys [43.7%] and 825 girls [56.3%]) with elevated apo B levels and/or apo B:apo A-I ratios for further testing, either by us or by their family doctor (overall estimated compliance rate up to 70%). Among the 458 children who returned to us, there was a 90% positive predictive value for a total cholesterol level of over 4.5 mmol/L in those with both elevated apo B levels and high apo B:apo A-I ratios. Girls had higher apo B levels and apo B:apo A-I ratios than boys (P < 0.00001 for both), and in both sexes there was a trend downwards for apo B and upwards for apo B:apo A-I ratio over the age range tested, but levels were relatively stable between the ages of 6 and 10 years. Indian children (1.5% of the screened population) had the highest apo B levels, followed by white children (71.1%); Asian children (9.2%) had the lowest (P < 0.00001 compared with Indian and white children).

CONCLUSIONS

The high positive predictive value of capillary blood apolipoprotein levels for an adverse lipid profile in children suggests that measuring apolipoprotein levels by this method is a useful initial approach to cardiovascular risk assessment.