LDL size and subclass pattern in Mexico City residents and San Antonio Mexican Americans

Recent studies suggest that a relative abundance of small dense LDL is a risk factor for coronary heart disease. We compared LDL size in Mexico City residents (n = 191) and San Antonio Mexican Americans (n = 282), two genetically similar populations that differ markedly in dietary behaviors: in Mexico City approximately 62% of calories are from carbohydrate and approximately 19% from fat, and in San Antonio approximately 40% of calories are from carbohydrate and approximately 40% from fat. Mean LDL size in Mexico City was 258.6 +/- 0.9 A, and in San Antonio, 255.9 +/- 0.6 A (P = .013). After adjustment for the higher triglyceride and lower HDL cholesterol levels (the two most important predictors of LDL size) in Mexico City, LDL size was significantly lower in San Antonio than in Mexico City by -8.33 +/- 0.84 A (P < .001). Our data suggest that the higher triglyceride concentrations in Mexico City residents that are associated with a higher carbohydrate diet may not be associated with atherogenic changes in LDL.