A modified equation for calculating low density lipoprotein cholesterol in Pakistani population

Main Article Content

Amjad Nawaz
Madeeha Khan
Quratul Ain
Hijab Batool
Muhammad Dilawar Khan
Mohammad Iqbal Khan
Fouzia Sadiq


OBJECTIVE: To derive an equation for accurate estimation of low-density lipoprotein cholesterol  (LDL-C) in the Pakistani population.

METHODS: A modified equation was derived on the dataset (n = 59,148) from the Pakistani population, comprising directly measured LDL-C (dLDL-C) and other lipids using a regression model. The equation was validated on an internal (n = 29,633) and external dataset (n = 385,434), and the results were compared with the standard equations being used in the Pakistani population: Friedewald and Teerakanchana equation. The concordance between the dLDL-C and calculated LDL-C (cLDL-C) was determined by median difference (MD) and the agreement between dLDL-C and cLDL-C was analyzed by Bland Altman graphics.

RESULTS: The modified equation (M.Eq) displayed best correlation (r = 0.974) and MD of -0.07 mmol/L on the derivation dataset. Similarly, the equation provided the best correlation and least MD on the internal (r = 0.970, MD = -0.13) and external validation datasets (r = 0.953, MD = -0.02). The Bland-Altman plot for the modified equation displayed the least bias in the derivation (-0.0012 mmol/L), internal validation (-0.13 mmol/L), and external validation (-0.02 mmol/L).

CONCLUSION: The modified equation can be utilized for clinical settings in Pakistan that do not facilitate direct measurements of LDL-C.

Article Details

How to Cite
Nawaz, A., M. Khan, Q. Ain, H. Batool, M. D. Khan, M. I. Khan, and F. Sadiq. “A Modified Equation for Calculating Low Density Lipoprotein Cholesterol in Pakistani Population”. KHYBER MEDICAL UNIVERSITY JOURNAL, vol. 15, no. 4, Dec. 2023, pp. 223-8, doi:10.35845/kmuj.2023.23439.
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