Impact of improved low-density lipoprotein cholesterol assessment on guideline classification in the modern treatment era-Results from a racially diverse Brazilian cross-sectional study.

BACKGROUND

The Martin/Hopkins low-density lipoprotein cholesterol equation (LDL-C) was previously demonstrated as more accurate than Friedewald LDL-C estimation (LDL-C) in a North American database not able to take race into account.

OBJECTIVES

We hypothesized that LDL-C would be more accurate than LDL-C and correlate better with LDL particle number (LDL-P) in a racially diverse Brazilian cohort.

METHODS

We performed a cross-sectional analysis of 4897 participants in the Brazilian Longitudinal Study of Adult Health, assessing LDL-C and LDL-C accuracy via overlap with ultracentrifugation-based measurement among clinical guideline LDL-C categories as well as mg/dL and percent error differences. We analyzed by triglyceride categories and correlated LDL-C estimation with LDL-P.

RESULTS

LDL-C demonstrated improved accuracy at 70 to <100 and <70 mg/dL (P < .001), with large errors ≥20 mg/dL about 9 times more frequent in LDL-C at LDL-C <70 mg/dL, mainly due to underestimation. Among individuals with LDL-C <70 mg/dL and triglycerides ≥150 mg/dL, 65% vs 100% of ultracentrifugation-based low-density lipoprotein cholesterol calculation fell within appropriate categories of estimated LDL-C and LDL-C, respectively (P < .001). Similar results were observed when analyzed for age, sex, and race. Participants at LDL-C <70 and 70 to <100 mg/dL with discordantly elevated LDL-C vs LDL-C had a 58.5% and 41.5% higher LDL-P than those with concordance (P < .0001), respectively.

CONCLUSIONS

In a diverse Brazilian cohort, LDL-C was more accurate than LDL-C at low LDL-C and high triglycerides. LDL-C may avoid underestimation of LDL-C and better reflect atherogenic lipid burden in low particle size, high particle count states.