Extreme lipoprotein(a) levels in hypercholesterolemic patients: Relevance and management in pediatric population

Introduction: Elevated lipoprotein(a) levels have been considered a causal risk factor for coronary artery disease (CAD) since many years. Due to its biochemical structure, lipoprotein(a) may contribute to both atherosclerosis and thrombosis. Few data are available in hypercholesterolemic children. Materials and methods: the aim of this study is to evaluate the prevalence of extreme lipoprotein(a) levels in hypercholesterolemic children referring to our Lipid Center and to develop a clinical management strategy. In a 12 months-period, 50 patients were referred to our Lipid Center for hypercholesterolemia. 14/50 (28%) matched clinical criteria for suspected familial hypercholesterolemia and underwent further analysis, included dosage of lipoprotein(a). Extreme lipoprotein(a) levels were defined as higher than 90th centile in two different blood samples, considering adult centile as no pediatric centile are available so far. Patients with extreme lipoprotein(a) levels underwent a thrombophilic panel screening (thromboplastin partial time, prothrombin time, mutation of V factor and II factor, dosage of protein c , protein S and antithrombin III). Haematologic evaluation and detailed CAD-oriented family history collection were also performed. Results: 1/14 patients showed lipoprotein(a) levels higher than 90th centile. 1/14 patient showed lipoprotein(a) level higher than 99th centile. Among these two patients, 2/2 had positive family history for hypercholesterolemia, 1/2 had positive family history for CAD and for thrombosis. Thrombophilic screening showed no abnormalities. Specific dietetic and lifestyle indications for hypercholesterolemia were given. Conclusions: Despite no specific pharmacological treatment is recommended yet in pediatric patients with extreme lipoprotein(a) levels, lipoprotein(a) levels determination is advisable in selected hypercholesterolemic patients. Detecting pediatric patients with extreme lipoprotein( a) levels is important in order to detect possible other pro-thrombosis risk factors. Moreover, patients and their families are educated to avoid the acquisition of other risk factors, such as smoking and weight excess, and to lead a healthy lifestyle, in order to preserve their cardiovascular health.