LDL hypercholesterolemia in children: genetic influence and response to lifestyle advice - follow-up of the Fr1dolin-trial

Abstract

Although familial hypercholesterolemia (FH) is common and associated with significant cardiovascular morbidity, screening programs are scarce. Furthermore, the effectiveness of nutritional advice for parents on children’s LDL cholesterol (LDL-C) levels is unclear, especially in FH versus non-FH hypercholesterolemia. In the Fr1dolin study, 367 of 14,513 children in Lower Saxony and Hamburg were positively screened for LDL hypercholesterolemia with an LDL-C > 135 mg/dl (> 3.5 mmol/l). The screening was considered positive if the first finding of hypercholesterolemia was confirmed in a second sample. These 367 children were invited to a follow-up examination including an extended lipid status, nutritional counseling and genetic analysis. 289 out of 367 screen-positive children (57.4% girls) were followed up for 12 months; 191 (66.1%) underwent genetic testing. Children with a FH-causing pathogenic or likely pathogenic variant (n = 40, 20.9%) had significantly higher LDL-C levels than children without a variant or with a variant of uncertain significance (p < 0.001). After the nutritional counselling and after 6 and 12 months of follow-up, LDL-C levels did not improve significantly (median LDL-C at baseline 142 mg/dl, and 140 mg/dl at 6 and 12 months follow-up, respectively). A population-based screening program detects LDL-hypercholesterolemia in up to 2.5% of children, with a significant proportion of them having FH genetic variants, supporting early detection. One-time nutritional advice had little effect on LDL-C in general, but particularly in FH, highlighting on the one hand need for structured lifestyle programs and on the other hand early genetic testing in population based FH screening.