Correlations between Direct and Calculated Low-Density Lipoprotein Cholesterol Measurements in Children and Adolescents.

BACKGROUND: Low-density lipoprotein cholesterol (LDL-C), as a modifiable risk factor for atherosclerotic cardiovascular disease, should be assessed and monitored. This study compared directly measured and Friedewald-estimated LDL-C values in children and adolescents. METHODS: Blood samples were collected from 464 children and adolescents. Calculated LDL-C (CLDL-C) levels were estimated using the Friedewald formula for any triglyceride value below 4.6 mmol/L. Direct LDL-C (DLDL-C) levels were measured on an ARCHITECT c8000 Abbott Clinical Chemistry Analyzer. The differences in LDL-C were then calculated. RESULTS: The correlation coefficients (R) between DLDL-C and CLDL-C were 0.978 (P = .148) and R = 0.970 (P = .052) for children and adolescents, respectively. Children with LDL-C values above 4.92 mmol/L had a correlation value of 0.971 (P = .419). The correlation and agreement between DLDL-C and CLDL-C in adolescents were moderate for LDL-C below 2.85 mmol/L (R = 0.806; 84.1%) and improved above 2.85 mmol/L (R = 0.978; 91.5%). In children, good correlations between DLDL-C and CLDL-C were observed for normal (<0.85 mmol/L), borderline (0.85-1.12 mmol/L), and abnormal (≥1.13 mmol/L) triglyceride levels (R = 0.9782, 0.990, and 0.951, respectively). The rates of agreement were better for normal (80.5%) and borderline (82.9%) but not abnormal (68.2%) triglyceride levels. CONCLUSION: We observed good agreement between DLDL-C and CLDL-C in both children and adolescents. The Friedewald formula provided an adequate estimate of LDL-C for most fasting specimens. LDL-C difference percentage can also be used as a quality indicator to check laboratory analyzer performance in healthy subjects.

Cardiometabolic risk among Saudi children and adolescents: Saudi childrens overweight, obesity, and lifestyles (S.Ch.O.O.Ls) study.

BACKGROUND AND OBJECTIVES: Diabetes and atherosclerotic cardiovascular disease are major contributors to the global burden of disease, with a high reported prevalence of risk factors among different populations. Early and efficient assessment of cardiometabolic risk is important to identify target groups for preventive interventions. The aims of Saudi children's overweight, obesity, and lifestyles study were to estimate the prevalence of the metabolic syndrome and to compare the different paradigms of assessing such risk among children and adolescents. The study was funded by National Guard Health Affairs and approved by the ethics committee. DESIGN AND SETTINGS: A cross-sectional study of students from primary, middle, and secondary schools located in the residential areas for the Saudi National Guard employees in Riyadh. METHODS: A random sample of 2149 students, clustered by school and stratified by grade, was selected from a sampling frame of 16 812 students from 10 schools in the residential areas for Saudi National Guard employees. Informed consent was taken from children and parents. Blood pressure, height, weight, waist circumference, and hip circumference were documented. Fasting blood samples were taken for blood glucose and lipid profile. RESULTS: The prevalence of metabolic syndrome ranged from 2% to 18%, according to the sensitivity of the 6 different definitions. Systolic blood pressure and triglycerides-to-HDL (high-density lipoprotein) ratio showed a dose-response increase with the quartiles of waist circumference and body mass index (BMI). Assessment of cardiometabolic risk by diagnosing the metabolic syndrome would lead to missed opportunity of intervention in 94% to 95% of children identified to be in need of intervention by waist circumference and BMI above 75th percentile. CONCLUSION: Relying on the diagnosis of the metabolic syndrome can harm primary preventive initiatives. BMI and waist circumference for age should be used for assessing cardiometabolic risk in children and adolescents.