Comparison of modified Friedewald's formula with direct measurement of low-density lipoprotein cholesterol in Bangladeshi population.

ABSTRACT

A modification of Friedewald's formula to estimate serum low-density lipoprotein cholesterol (LDLC) up to serum triglyceride (TG) level of 11.3 mmol/L in Bangladeshi population has recently been published. The aim of this study was to compare the modified formula with direct measurement of LDLC in Bangladeshi population in a different setting. One thousand and fifty two specimens from adult subjects were analyzed. Serum total cholesterol (TC), high-density lipoprotein cholesterol (HDLC), LDLC and TG were measured by standard methods. The modified Friedewald's formula was applied to estimate LDL cholesterol concentration. Results were expressed as mean ± SD and calculated LDLC was compared with measured LDLC by two-tailed paired t test, Bland-Altman plot for absolute bias, Pearson's correlation coefficients of calculated LDLC with measured LDLC and Passing & Bablok regression equation of calculated LDLC against measured LDLC. The mean ± SD of measured LDLC was 2.98 ± 0.82 mmol/L. LDLC calculated by modified Friedewald's formula was 2.77 ± 0.86 mmol/L. The mean absolute bias was -0.20 ± 0.32 mmol/L, Pearson's correlation coefficient (r) was 0.9293 (P < 0.0001) and Passing & Bablok regression equation was y = - 0.3856+1.0597x for modified formula up to serum TG ≤ 11.3 mmol/L. Compared to original Friedewald's formula, performance of the modified Friedewald's formula was better up to serum TG ≤ 4.52 mmol/L. The study reveals that the modified Friedewald's formula may be used to calculate LDLC approximately in Bangladeshi population.