Lipoprotein (a) concentration is associated with plasma arachidonic acid in subjects with familial hypercholesterolemia

Elevated lipoprotein (a) (Lp[a]) is associated with cardiovascular disease (CVD) and is mainly genetically determined. Studies suggest a role of dietary fatty acids (FAs) in the regulation of Lp(a), however, no studies have investigated the association between plasma Lp(a) concentration and omega-6 FAs. We aimed to investigate whether plasma Lp(a) concentration was associated with dietary omega-6 FA intake, and plasma levels of arachidonic acid in subjects with familial hypercholesterolemia (FH). We included FH subjects with (n=68) and without (n=77) elevated Lp(a) defined as ≥75 nmol/L, and healthy subjects (n=14). Total fatty acid profile was analyzed by Gas Chromatography-Flame Ionization Detector analysis, and the daily intake of macronutrients (including the sum of omega-6 FAs: 18:2n-6, 20:2n-6, 20:3n-6 and 20:4n-6) were computed from completed food frequency questionnaires. FH subjects with elevated Lp(a) had higher plasma levels of arachidonic acid (AA) compared to FH subjects without elevated Lp(a) (P=0.03). Furthermore, both FH subjects with and without elevated Lp(a) had higher plasma levels of AA compared to controls (P<0.001). The multivariable analyses showed associations between dietary omega-6 FA intake and plasma levels of AA (P=0.02), and between plasma levels of Lp(a) and AA (P=0.006). Our data suggest a novel link between plasma Lp(a) concentration, dietary omega-6 FAs and plasma AA concentration, which may contribute to explain the small diet-induced increase in Lp(a) levels associated with lifestyle changes. Although the increase may not be clinically relevant, this association may be mechanistically interesting in understanding more of the role and regulation of Lp(a)

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