Comparison between Friedewald's and Sampson's formulas in the estimation of high levels of measured LDL-cholesterol in youth with obesity.

Background and Aim: To assess the performance of Friedewald's and Sampson's formulas in relation to high or borderline-high levels of measured LDL-Cholesterol (LDL-C) in youths with overweight/obesity (OW/OB).
Methods and Results: A cross-sectional study was performed in 1694 youths (age 5-17 years) with OW/OB observed in Italian centers of Messina (group 1) and Naples (group 2). LDL-C levels were both measured and calculated using Friedewald's (LDL-C _F ) and Sampson's (LDL-C _S ) formulas. The two groups were similar for sex, age, BMI, BMI Z-score, and measured LDL-C. Levels of LDL-C _F and LDL-C _S were higher in group 1 than group 2. In the overall sample, 9.9 % youths had measured LDL-C ≥130 mg/dL and 27.8 % ≥ 110 mg/dL, without differences between centers. The two formulas showed comparable high sensitivity and specificity in relation to levels of measured LDL-C ≥130 mg/dL or ≥110 mg/dL. However, LDL-C _F showed a higher positive predictive value than LDL-C _S .
Conclusions: Both formulas estimate with high accuracy measured LDL-C levels in youths with OW/OB. Therefore, calculated LDL-C can be a useful tool for universal screening when direct LDL-C measurement is not available. The Friedewald's formula is more feasible in clinical practice for simplicity of calculation.
Competing Interests: Declaration of competing interest The authors have no conflicts of interest to disclose.
(Copyright © 2024 The Italian Diabetes Society, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.)