Distribution and correlates of non–high-density lipoprotein cholesterol and triglycerides in Lebanese school children

The associations between prenatal phthalate exposure and childhood glycolipid metabolism and blood pressure: An updated systematic review and a pilot meta-analysis of prospective cohort studies

This is the first pilot meta-analysis on the association of prenatal phthalate exposure with childhood cardiometabolic risks. A systematic literature search was performed in MEDLINE, Web of Science and CNKI (Chinese National Knowledge Infrastructure) until June 5, 2023. A total of seven studies with 5746 children (2646 girls and 3100 boys) were finally included. Four, three and two studies investigated the effects of maternal phthalate exposure on childhood blood pressure (BP), blood lipids and blood glucose profiles, respectively. The pilot meta-analysis suggested that di-2-ethylhexyl phthalate (DEHP) metabolite exposure was associated with a decrease in childhood z-systolic BP (SBP, β = -0.169, 95% CI = -0.338-0.001). Furthermore, the pooled results showed negative relationships of prenatal ∑DEHP exposure with z-SBP (β = -0.109, 95% CI = -0.163 to -0.055) and z-diastolic BP (DBP, β = -0.126, 95% CI = -0.182 to -0.069) in girls. In addition, MEP exposure was associated with z-SBP in girls (β = -0.227, 95% CI = -0.387 to -0.066). The pooled result showed a positive relationship between prenatal ∑DEHP exposure and triglycerides (β = 0.103, 95% CI = 0.028-0.178). The overall results revealed that exposure to ∑DEHP throughout gestation was associated with a decrease in insulin (β = -0.074, 95% CI = -0.144 to -0.004) and glucose (β = -0.129, 95% CI = -0.199 to -0.058) in boys. Interestingly, there was an inverse relationship of prenatal mono- 3 -carboxypropyl phthalate (MCPP) exposure with glucose in pubertal boys (β = -3.749, 95% CIs = -6.758 to -0.741) but not found in postpubertal children. In conclusion, prenatal phthalate exposure interfered with cardiovascular risk in children with gender-specific differences and was influenced by puberty. Overall, prenatal ∑DEHP was negatively associated with systolic blood pressure in girls and with insulin and glucose in boys but increased the level of triglycerides.

Lipid Parameters and Proprotein Convertase Subtilisin/Kexin Type 9 in Healthy Lebanese Adults

Background: High levels of non-HDL cholesterol (non-HDL-C), triglycerides (TG), lipoprotein (a) (Lp(a)), and Proprotein convertase subtilisin/kexin type 9 (PCSK9) as well as low levels of HDL-C are strongly associated with cardiovascular disease (CVD). Our study aims to estimate the prevalence of dyslipidemia and high Lp(a) in the Lebanese population and to study the relationship of these variables with gender, age, body mass index (BMI), and PCSK9. Methods: This cross-sectional study was carried out on a sample of healthy volunteers aged 18 to 65. Blood samples were drawn from volunteers for total cholesterol (TC), HDL-C, TG, PCSK9, and Lp(a) measurements. Non-HDL-C was calculated by subtracting HDL-C from TC. Results: In total, 303 volunteer subjects with an average age of 38.9 years were included in the study. Respectively, 44%, 29.8%, and 44% of men had high non-HDL-C and TG with low HDL-C versus 23.5%, 8%, and 37% in women. Non-HDL-C and TG were significantly higher in men than in women, while the reverse was observed for HDL-C (p < 0.0001 for the three comparisons). Non-HDL-C and TG were significantly correlated with age and BMI (p< 0.0001 for all correlations), while HDL-C was inversely correlated with BMI (p < 0.0001) but not with age. Abnormal Lp(a) levels (≥75 nmol/L) were found in 19.1% of the population, predominantly in women (24.1% versus 13.4% in men, p = 0.004). The median PCSK9 and its interquartile was 300 (254−382) ng/L with no gender difference (p = 0.18). None of the following factors: gender, age, BMI, non-HDL-C, HDL-C, or TG, were independently associated with Lp(a), while PCSK9 was significantly correlated with age, non-HDL-C, and TG in both men and women and inversely correlated with HDL-C in men. Dyslipidemia is very common in the Lebanese population and is associated with age, high BMI, and male sex. Lp(a) is higher in women without any correlation with the lipid profile, whereas PCSK9 is associated with non-HDL-C and TG. Further studies are needed to evaluate the potential role of Lp(a) and PCSK9 in predicting CVD in healthy populations.

Circulating PCSK9 Linked to Dyslipidemia in Lebanese Schoolchildren

In adults, elevated levels of circulating Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) have been associated with increased Low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and worse cardiovascular outcomes. However, few studies analyzed the relation between PCSK9 and lipid parameters in pediatric populations. The aim of our study is to evaluate the distribution and the correlation of serum PCSK9 levels with lipid parameters in a sample of Lebanese school children. Using an immunofluorescence assay, we measured serum PCSK9 levels in 681 school children recruited from ten public and private Lebanese schools. We analyzed the association between PCSK9 and age, sex, Body Mass Index (BMI), and lipid parameters (total cholesterol (TC), LDL-C, TG, High-density lipoprotein cholesterol (HDL-C), non-HDL-C, and lipoprotein (a) (Lp(a)). Serum PCSK9 levels were significantly correlated with TC, LDL-C, and non-HDL-C (p value < 0.0001) but not with TG, HDL-C, and Lp(a). PCSK9 levels were also significantly higher in children with high TC, LDL-C, and non-HDL-C (p values = 0.0012, 0.0002, 0.001, respectively). No significant gender differences in PCSK9 were found. In addition, no significant associations between PCSK9 and both age and BMI percentiles were observed. In girls, no difference in PCSK9 values was observed according to menarche while in boys, testosterone levels were not significantly associated with PCSK9. Serum PCSK9 levels were significantly correlated with TC, LDL-C, and non-HDL-C levels. Further studies are needed to find if PCSK9 measurements have an additional value to predict future cardiovascular outcomes in pediatric populations.

Identification of Factors Influencing Cholesterol Changes in Elementary-School Children: A Longitudinal Study

Changes in serum cholesterol levels during childhood may affect the risk of cardiovascular disease in adulthood. However, cholesterol level changes in Japanese children and adolescents and the factors that influence them have not been completely elucidated. This study aimed to determine whether cholesterol levels changed due to the effects of growth and identify factors. This cohort study included elementary-school children in the fourth grade (9−10-year-old) who underwent assessments of cholesterol levels and demographic and lifestyle characteristics. The participants were followed up in their first year of junior high school with the same laboratory, demographic, and lifestyle assessments. From the fourth year of elementary school to the first year of junior high school, children’s cholesterol levels decreased (p < 0.0001). Regarding bowel movements, cholesterol level reduction was significant in individuals with regular bowel movements but not significant in those with infrequent bowel movements. Weight was the factor that most strongly negatively predicted cholesterol level reduction (p < 0.001). The study demonstrated the significance of lifestyle factors for growth-related changes of total cholesterol levels and identified weight as the factor that most strongly influenced total cholesterol level changes. Guidance regarding lifestyle improvements should be imparted to children from the fourth grade of elementary school.

Prevalence and status of Lipoprotein (a) among Lebanese school children

Lipoprotein a (Lp(a) is an independent risk factor for atherosclerotic cardiovascular disease. The prevalence of high Lipoprotein (a) (Lp(a)) in the Lebanese pediatric population is unknown. Our study aims to assess this prevalence and to study the relationship of Lp(a) with the lipid profile, age, body mass index (BMI) and socio-economic status (SES) in Lebanese schoolchildren. A total of 961 children aged 8–18 years (497 boys and 464 girls) were recruited from ten private and public schools in 2013–2014 using a stratified random sample. Schools were selected from the Greater Beirut and Mount Lebanon areas, and were categorized into three subgroups according to the schools’ SES status (high, medium, low). Lp(a) was assayed in 2018 on samples previously frozen at − 80 °C. Abnormal Lp(a) levels (≥ 75 nmol/L) were observed in 14.4% of the overall sample (13.5% for boys,15.3% of girls p = 0.56). The median of Lp(a) was 20(10–50) in the whole sample with no significant gender difference. No significant relationship was found between Lp(a) and age. However, Lp(a) was significantly correlated with BMI in whole sample, as well as in boys and girls (p = 0.02, p = 0.03, p = 0.03, respectively). A significant correlation was found between Lp(a) and non-HDL-C in the whole sample as well as in boys and girls (respectively p < 0.001,p = 0.024 and p = 0.03), but not with triglycerides and HDL-C. In a multivariate linear regression analysis, Lp(a) was only independently associated with BMI and non-HDL-C in boys and girls. Lp(a) was independently associated with BMI and non-HDL-C while no significant relationship was observed with age and sex confirming the strong genetic determination of Lp(a).

Prevalence of Iron deficiency in Lebanese schoolchildren

BACKGROUND

The prevalence of iron deficiency in the Lebanese pediatric population is unknown. The aim of this study is to estimate this prevalence in Lebanese schoolchildren and to assess the relation between iron status and related factors.

SUBJECTS/METHODS

A total of 903 children aged 8-18 years (466 boys and 437 girls) were included in the study. Recruitment was done from ten schools with different SES levels and located in the Great Beirut and Mount Lebanon areas. Serum ferritin was measured in all participants and testosterone was measured only in boys using Immulite chemiluminescent assays.

RESULTS

For the entire sample, the median serum ferritin concentration was 30.0 [19.8-44.8] ng/mL and the prevalence of iron deficiency (ferritin < 15 ng/mL) was 14.2%. Iron deficiency was higher in girls compared with boys (respectively, 20.8% and 7.9%). This prevalence varied with the SES (respectively, 11.6%, 11.9%, and 16.8% in high, middle, and low SES, p = 0.09). Iron deficiency increased with age (9.5%, 15.7%, and 17.5%, respectively, for the age groups 8-11, 12-14, and 15-18, p = 0.014) and did not differ between normal, overweight, and obese groups (p = 0.07). In boys, a significant positive correlation was observed between ferritin and total testosterone (rho = 0.150, p = 0.001).

CONCLUSION

The prevalence of iron deficiency is relatively low in Lebanon. Younger boys, menstruating girls, and children from low SES are more prone to iron deficiency, while BMI has no impact.

Universal screening program for lipid disorders in 2-10 years old Lebanese children: A new approach

Introduction

Dyslipidemia has been recognized as a risk factor for cardiovascular diseases. Studies have showed that the development of atherosclerotic lesions begins in childhood and progresses throughout life. While the prevalence of dyslipidemia in adults has been reported to be 10 times higher in Lebanon compared to Western countries, data on the prevalence of dyslipidemic children in Lebanon is lacking.

Objectives

This study was conducted to assess the benefit of a protocol for universal screening for lipid disorders in Lebanese children aged between two and ten years old.

Materials and methods

A total of four hundred children aged 2–10 years old (51.5% boys) were included in the study. The subjects were recruited from private pediatric clinics after parental consent. Fasting total cholesterol (TC), triglycerides (TG), low density lipoprotein (LDL), high density lipoprotein (HDL) levels were measured and non-HDL cholesterol was calculated. The values were categorized according to 2011 Expert Panel on Integrated Guidelines for Cardiovascular Health and Risk Reduction in Children and Adolescents.

Results

The overall prevalence of high TC (≥200 mg/dL), high non-HDL-C (≥145 mg/dL), high LDL (≥130 mg/dL), high TG (≥100 mg/dL) and low HDL (<40 mg/dL) was respectively 19.5%, 23%, 19%, 31.8% and 20%. The overall frequency of dyslipidemia was 51.7%. In a bivariate analysis, dyslipidemia in children was associated with a BMI ≥95th percentile and parents having TC > 240 mg/dL with a P value respectively of .006 and .0001. Furthermore, high TG was independently associated with a BMI ≥95th percentile (P = .0001). Children with parents having TC > 240 mg/dL was significantly correlated with high TC, high non-HDL-C and high LDL (P = .0001 for all variables). Finally, according to the Pediatric Dyslipidemia Screening Guidelines from the 2011 Expert Panel, 62.3% of dyslipidemic children had at least 1 risk factor that qualified them for screening while 37.7% of them didn't have any risk factor.

Conclusions

It is preferable to review the latest pediatric dyslipidemia screening guidelines by performing a universal screening program since a third of our dyslipidemic Lebanese children will be missed.

Longitudinal changes of lipid profile in the Lebanese pediatric population

Background

Few studies looked at the prevalence of dyslipidemia in pediatric Middle-Eastern countries. In addition, worldwide longitudinal changes of lipid profile is not well documented. The purpose of this study is to look at the longitudinal changes of lipid parameters in Lebanese school-age children.

Materials and methods

A total of 97 subjects (41 girls and 56 boys) aged between 11 and 21 years were included in this study. The subjects were selected among 339 school-age children with a previous abnormal lipid profile who were recruited from 10 schools of varying socio-economic levels (SEL). A fasting lipid profile [total cholesterol (TC), triglycerides (TG) and HDL-cholesterol (HDL-C)] was performed. Non-HDL-cholesterol (Non-HDL-C) was calculated. Weight and height were measured under the same conditions, and BMI percentiles were calculated. A multivariate covariance analysis model (MANCOVA) was used with TG, HDL-C and non-HDL-C as dependent variables with additional post-MANCOVA F tests.

Results

The age of the current cohort is 16.5 ± 2.9 years with no significant difference according to gender. The current lipid profile was obtained 3.1 ± 0.7 years following the initial one, with 53.6% of the subjects having it normalized. TC, TG, and non-HDL-C decreased significantly over time in girls, while only TG decreased significantly in boys. No significant changes were observed for HDL-C. Using MANCOVA, a significant time by age interaction was observed (p < 0.0001), while gender, BMI and SEL were found not to be significant. Post-hoc F tests showed that the time by age interaction was driven by TG (p = 0.03) and non-HDL-C (p < 0.001), the larger effect being observed in younger children.

Conclusion

A high proportion of school-age children normalize their abnormal lipid profile with time. Screening for lipid disorders could be postponed until post puberty age.

Relationship between 25 hydroxyvitamin D and lipid profile in Lebanese school children

PURPOSE

Limited information is available regarding the association of vitamin D and lipid profile in pediatric populations. The objective of this cross-sectional study is to determine the prevalence of vitamin D deficiency in a large sample of Lebanese schoolchildren and to evaluate the relationship between vitamin D and lipid profile.

METHODS

969 Lebanese schoolchildren (505 boys and 464 girls) aged 8-18 years were recruited from 10 schools of different socioeconomic status (SES). Non-fasting total cholesterol, triglycerides and HDL-Cholesterol (HDL-C) were measured. Non-HDL-C was calculated.

RESULTS

The prevalence of 25(OH)D deficiency (level below 20 ng/ml) is 56.6% (48.1% in boys, 65.7% in girls). There is no significant relationship between 25(OH)D levels and age. 25(OH)D is inversely correlated with BMI in the total population, and in boys and girls (p < 0.0001, p = 0.001 and p = 0.001, respectively) and is higher in children from high SES schools and during the summer season (p < 0.0001 in both cases). 25(OH)D is inversely correlated with triglycerides and non-HDL-C in the total population and in boys and girls (p < 0.0001 for all), and positively correlated with HDL-C in the total population and in boys but not in girls (p = 0.001, p < 0.0001 and p = 0.1, respectively). In a multilinear regression analysis, in the overall population, 25(OH)D is independently associated with sex, season, school's SES, BMI, triglycerides and non-HDL-C. In boys, the association with BMI and season is non-significant.

CONCLUSION

An independent relationship is observed between 25(OH)D and cardiometabolic risk factors in the pediatric Lebanese population Further studies are needed to evaluate the long-term consequences of this relationship.