Lipoprotein(a) levels from childhood to adulthood: Data in nearly 3,000 children who visited a pediatric lipid clinic

Background and aims: Elevated lipoprotein(a) [Lp(a)] is an independent risk factor for cardiovascular disease. In clinical practice, Lp(a) is mostly measured only once assuming that it does not change with age nor vary within individuals. This is mainly based on adult data and data on Lp(a) levels during childhood is scarce. Therefore, we evaluated whether Lp(a) levels changed with age and determined the intra-individual variation of Lp(a) in a large cohort of children. Methods: We collected all Lp(a) measurements of children referred to the pediatric lipid clinic of the Amsterdam UMC between 1989 and 2017. The association between Lp(a) and age, as well as the intra-individual variation of Lp(a), was assessed using mixed models. We stratified for lipid-lowering medication use. Results: In total, we included 2740 children. From the age of 8 years onwards, mean Lp(a) increased with 22% in children that reached adulthood without lipid-lowering medication (n = 2254). In statin-users (n = 418) and children that used ezetimibe additionally (n = 65), Lp(a) increased with 43% and 9%, respectively. The intra-individual variation of Lp(a) was 70%. Conclusions: Lp(a) levels increase with age and exhibit considerable variation within children referred to a lipid clinic. Measuring Lp(a) only once during childhood might therefore lead to substantial over- or underestimation and possibly result in over- or under treatment in the future. Thus, to more accurately assess the Lp(a) level, we suggest measuring Lp(a) more than once during childhood and to repeat this in adulthood if a patient only has childhood assessment of Lp(a).