Lipid profile in Portuguese obese children and adolescents: interaction of apolipoprotein E polymorphism with adiponectin levels.

ABSTRACT

OBJECTIVE: To evaluate how the lipid profile associates with apolipoprotein (apo) E gene polymorphism, plasma adiponectin level, and body mass index (BMI) z score in Portuguese youth. DESIGN: Transversal cohort study. SETTING: Hospital de São João and Hospital de Crianças Maria Pia, Porto, Portugal, between May 2006 and March 2007. PARTICIPANTS: One hundred thirty-eight obese children and adolescents (62 boys; mean age, 10.8 years [range, 4-16 years]). Participants were grouped according to (1) apo E polymorphism presence of the apo E alleles 2 or 4 in E2 (n = 11) and E4 (n = 31) carriers, respectively, or as E3/E3 (n = 94) (carriers of E2/E4 [n = 2] were excluded from apo E analysis because they carry both alleles) and (2) BMI z score group 1, BMI z score less than 2 (n = 31); group 2, BMI z score of 2 or more and less than 2.5 (n = 65); and group 3, BMI z score of 2.5 or more (n = 42). MAIN OUTCOME MEASURES: Lipid variable comparisons between apo E polymorphism and BMI z score groups and influence of BMI z score and adiponectin level, adjusted for apo E polymorphism, on total cholesterol to high-density lipoprotein cholesterol and apo A-I to apo B ratios. RESULTS: E4 carriers presented with a worse lipid profile when compared with E2 and E3/E3 carriers. There was also a clear risk of worsening for the group with the highest BMI z score. Apolipoprotein E polymorphism, BMI z score, and adiponectin level were significantly associated with total cholesterol to high-density lipoprotein cholesterol (standardized beta coefficient = 0.283, 0.354, and -0.292, respectively; P < .001 for all) and apo A-I to apo B (standardized beta coefficient = -0.372, -0.284, and 0.327, respectively; P < .001 for all) ratios. CONCLUSION: Our data suggest a more atherogenic lipid profile for some apo E genotypes and for increasing BMI z score, whereas adiponectin level seems to play a protective role.