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

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 ± SDof 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 inBangladeshi population.