Association of lipoprotein-associated phospholipase A₂ activity with components of the metabolic syndrome in apparently healthy boys.

BACKGROUND: Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) has been proposed as a biomarker of risk of cardiovascular disease (CVD).

OBJECTIVE: To determine the association between Lp-PLA(2) activity and BMI, insulin-resistance, components of the metabolic syndrome (MS), and lifestyle behaviors in healthy adolescent boys.

METHODS: Data were collected cross-sectionally from 164 adolescents from an amateur rugby club. BMI, blood pressure (BP), Tanner stages, glucose, insulin, lipids, and Lp-PLA(2) activity were measured. Questionnaires for lifestyle behaviors were completed.

RESULTS: Approximately 26% of the adolescents were obese and 23% overweight. There was a univariate association between Lp-PLA(2) and BMI (r=0.16;p=0.042), triglycerides (r=0.26;p=0.001), LDL-C (r=0.46;p<0.001), apo B (r=0.55;p<0.001), whereas waist circumference , BP, glucose, HOMA-IR, and HDL-C were not correlated. None of the lifestyle behaviors were significantly correlated with Lp-PLA(2). In order to analyze Lp-PLA(2) association with known CVD risk conditions, adolescents were categorized according to overweight/obesity and to the presence of metabolic syndrome. Conversely, as it was for LDL-C and apo B concentration, Lp-PLA(2) activity was not higher in adolescents with obesity. Multiple regression analysis showed that apo B was significantly associated with Lp-PLA(2) adjusted for age, BMI, triglycerides and LDL-C (R2=0.32).

CONCLUSION: Lp-PLA(2) activity was only associated with apo B adjusted for several confounding variables, suggesting that its clinical utility to identify individuals at risk for CVD does not surpass LDL-C and apo B in healthy adolescents. As plaque morphology may change with age, associations of Lp-PLA(2) with CVD may likewise vary with age.