Comparison of the characteristics at diagnosis and treatment of children with heterozygous familial hypercholesterolaemia (FH) from eight European countries

Background and aims: For children with heterozygous familial hypercholesterolaemia (HeFH), European guidelines recommend consideration of statin therapy by age 8-10 years for those with a low density lipoprotein cholesterol (LDL-C) >3.5 mmol/l, and dietary and lifestyle advice. Here we compare the characteristics and lipid levels in HeFH children from Norway, UK, Netherlands, Belgium, Czech Republic, Austria, Portugal and Greece. Methods: Fully-anonymized data were analysed at the London centre. Differences in registration and on treatment characteristics were compared by standard statistical tests. Results: Data was obtained from 3064 children. The median age at diagnosis differed significantly between countries (range 3-11 years) reflecting differences in diagnostic strategies. Mean (SD) LDL-C at diagnosis was 5.70 (±1.4) mmol/l, with 88% having LDL-C>4.0 mmol/l. The proportion of children older than 10 years at follow-up who were receiving statins varied significantly (99% in Greece, 56% in UK), as did the proportion taking Ezetimibe (0% in UK, 78% in Greece). Overall, treatment reduced LDL-C by between 28 and 57%, however, in those >10 years, 23% of on-treatment children still had LDL-C>3.5 mmol/l and 66% of those not on a statin had LDL-C>3.5 mmol/l. Conclusions: The age of HeFH diagnosis in children varies significantly across 8 countries, as does the proportion of those >10 years being treated with statin and/or ezetimibe. Approximately a quarter of the treated children and almost three quarters of the untreated children older than 10 years still have LDL-C concentrations over 3.5 mmol/l. These data suggest that many children with FH are not receiving the full potential benefit of early identification and appropriate lipid-lowering treatment according to recommendations.Highlights: The age of HeFH diagnosis varies significantly between 8 European countries; The proportion of HeFH children being treated varies across 8 European countries; A quarter of FH children on statins have LDL-C above the target (>3.5 mmol/L); Many FH children are not getting the full benefit of early diagnosis and treatment.The European Register is supported by a grant from the International Atherosclerosis Society (Pfizer number 24052829). The UK register is supported by funds from the British Heart Foundation (BHF); HEART UK, Cardiac Network Co-ordinating Group Wales and the Royal College of Physicians. SEH is a BHF Professor and is funded by PG08/008, and by the National Institute for Health Research University College London Hospitals Biomedical Research Centre. MF is funded by the Fondation Leducq Transatlantic Networks of Excellence Program grant (no. 14 CVD03). MV and TF are funded by the Ministry of Health of the Czech Republic (grant nr. 15-28277A). The Austrian FH register has been supported by funds from the Austrian Heart Foundation and the Tyrolean Regional Government.