Background About 7% of US adults have severe hypercholesterolemia (untreated LDL cholesterol ≥190 mg/dl). Such high LDL levels may be due to familial hypercholesterolemia (FH), a condition caused by a single mutation in any of three genes. Lifelong elevations in LDL cholesterol in FH mutation carriers may confer CAD risk beyond that captured by a single LDL cholesterol measurement. Objectives Assess the prevalence of a FH mutation among those with severe hypercholesterolemia and determine whether CAD risk varies according to mutation status beyond the observed LDL cholesterol. Methods Three genes causative for FH (LDLR, APOB, PCSK9) were sequenced in 26,025 participants from 7 case-control studies (5,540 CAD cases, 8,577 CAD-free controls) and 5 prospective cohort studies (11,908 participants). FH mutations included loss-of-function variants in LDLR, missense mutations in LDLR predicted to be damaging, and variants linked to FH in ClinVar, a clinical genetics database. Results Among 8,577 CAD-free control participants, 430 had LDL cholesterol ≥190 mg/dl; of these, only eight (1.9%) carried a FH mutation. Similarly, among 11,908 participants from 5 prospective cohorts, 956 had LDL cholesterol ≥190 mg/dl and of these, only 16 (1.7%) carried a FH mutation. Within any stratum of observed LDL cholesterol, risk of CAD was higher among FH mutation carriers when compared with non-carriers. When compared to a reference group with LDL cholesterol <130 mg/dl and no mutation, participants with LDL cholesterol ≥190 mg/dl and no FH mutation had six-fold higher risk for CAD (OR 6.0; 95%CI 5.2–6.9) whereas those with LDL cholesterol ≥190 mg/dl as well as a FH mutation demonstrated twenty-two fold increased risk (OR 22.3; 95%CI 10.7–53.2). Conclusions Among individuals with LDL cholesterol ≥190 mg/dl, gene sequencing identified a FH mutation in <2%. However, for any given observed LDL cholesterol, FH mutation carriers are at substantially increased risk for CAD.

BACKGROUND Familial combined hypolipidemia, a Mendelian condition characterized by substantial reductions in all 3 major lipid fractions, is caused by mutations that inactivate the gene angiopoietin-like 3 (ANGPTL3). Whether ANGPTL3 deficiency reduces risk of coronary artery disease (CAD) is unknown. OBJECTIVES The study goal was to leverage 3 distinct lines of evidence – a family that included individuals with complete (compound heterozygote) ANGPTL3 deficiency, a population based-study of humans with partial (heterozygote) ANGPTL3 deficiency, and biomarker levels in myocardial infarction (MI) patients – to test if ANGPTL3 deficiency is associated with lower risk for CAD. METHODS We assessed coronary atherosclerotic burden in 3 individuals with complete ANGPTL3 deficiency and 3 wild-type first-degree relatives using computed tomography angiography. In the population, ANGPTL3 loss-of-function (LOF) mutations were ascertained in up to 21,980 individuals with CAD and 158,200 controls. LOF mutations were defined as nonsense, frameshift, and splice-site variants, along with missense variants resulting in <25% of wild-type ANGPTL3 activity in a mouse model. In a biomarker study, circulating ANGPTL3 concentration was measured in 1,493 individuals presenting with MI and 3,232 controls. RESULTS The 3 individuals with complete ANGPTL3 deficiency showed no evidence of coronary atherosclerotic plaque. ANGPTL3 gene sequencing demonstrated that approximately 1 in 309 individuals was a heterozygous carrier for an LOF mutation. Compared to those without mutation, heterozygous carriers of ANGPTL3 LOF mutations demonstrated a 17% reduction in circulating triglycerides and a 12% reduction in low-density lipoprotein cholesterol. Carrier status was associated with a 34% reduction in odds of CAD (odds ratio: 0.66; 95% confidence interval: 0.44 to 0.98; p = 0.04). Individuals in the lowest tertile of circulating ANGPTL3 concentrations, compared with the highest, had reduced odds of MI (adjusted odds ratio: 0.65; 95% confidence interval: 0.55 to 0.77; p < 0.001). CONCLUSIONS ANGPTL3 deficiency is associated with protection from CAD.

ObjectiveTo investigate the efficacy and safety of the interleukin-6 receptor antibody tocilizumab in patients with Takayasu arteritis (TAK).MethodsPatients with TAK who had relapsed within the previous 12 weeks were induced into remission with oral glucocorticoid therapy. In this double-blind, placebo-controlled trial, patients were randomly assigned 1:1 to receive weekly tocilizumab 162 mg or placebo subcutaneously, and oral glucocorticoids were tapered 10 %/week from week 4 to a minimum of 0.1 mg/kg/day until 19 patients relapsed. The primary endpoint was time to relapse of TAK, defined as ≥2 of the following: objective systemic symptoms, subjective systemic symptoms, elevated inflammation markers, vascular signs and symptoms or ischaemic symptoms.ResultsThe intent-to-treat and safety populations included 18 tocilizumab-treated and 18 placebo-treated patients. The per-protocol set (PPS) included 16 tocilizumab-treated and 17 placebo-treated patients. HRs for time to relapse of TAK were 0.41 (95.41% CI 0.15 to 1.10; p=0.0596) in the intent-to-treat population (primary endpoint) based on relapse in eight tocilizumab-treated and 11 placebo-treated patients and 0.34 (95.41% CI 0.11 to 1.00; p=0.0345) in the PPS. The secondary endpoints, time to relapse assessed by Kerr’s definition and clinical symptoms only, were consistent with the primary endpoint. Serious adverse events were reported in one tocilizumab-treated and two placebo-treated patients. There were no serious infections and no deaths.ConclusionAlthough the primary endpoint was not met, the results suggest favour for tocilizumab over placebo for time to relapse of TAK without new safety concerns. Further investigation is warranted to confirm the efficacy of tocilizumab in patients with refractory TAK.Trial registration numberJapicCTI-142616.

BACKGROUND Genomic analyses have suggested that the LPA gene and its associated plasma biomarker, lipoprotein(a) (Lp[a]), represent a causal risk factor for coronary heart disease (CHD). As such, lowering Lp(a) has emerged as a therapeutic strategy. Beyond target identification, human genetics may contribute to the development of new therapies by defining the full spectrum of beneficial and adverse consequences and by developing a dose-response curve of target perturbation. OBJECTIVES We attempted to establish the full phenotypic impact of LPA gene variation and to estimate a dose-response curve between genetically altered plasma Lp(a) and risk for CHD. METHODS We leveraged genetic variants at the LPA gene from 3 data sources: individual-level data from 112,338 participants in the UK Biobank; summary association results from large-scale genome-wide association studies; and LPA gene sequencing results from cases with and controls free of CHD. RESULTS One standard deviation genetically lowered Lp(a) level was associated with 29% lower risk of CHD (odds ratio [OR]: 0.71; 95% confidence interval [CI]: 0.69 to 0.73), 31% lower risk of peripheral vascular disease (OR: 0.69; 95% CI: 0.59 to 0.80), 13% lower risk of stroke (OR: 0.87; 95% CI: 0.79 to 0.96), 17% lower risk of heart failure (OR: 0.83; 95% CI: 0.73 to 0.94), and 37% lower risk of aortic stenosis (OR: 0.63; 95% CI: 0.47 to 0.83). We observed no association with 31 other disorders including type 2 diabetes and cancer. Variants that led to gain of LPA gene function increased risk for CHD whereas those that led to loss of gene function reduced CHD risk. CONCLUSIONS Beyond CHD, genetically lowered Lp(a) is associated with a lower risk of peripheral vascular disease, stroke, heart failure, and aortic stenosis. As such, pharmacological lowering of plasma Lp(a) may impact a range of atherosclerosis-related diseases.