Familial Hypercholesterolemia is Still Underdiagnosed and Undertreated Familial hypercholesterolemia (FH) is a common genetic cause of premature coronary artery disease (CAD). Making an early ...diagnosis is essential to prevent early deaths. However, diagnostic rates of heterozygous FH in Japan have not been increased satisfactorily so far. Intensive lipid-lowering combination therapy is required for many of them to achieve goals of LDL-C. Treatments in FH without a diagnosis are generally insufficient, even in diagnosed FH. Diagnostic Criteria of FH in JAS and DLCN To make early diagnoses, spreading awareness and diagnostic criteria of FH in general practice, including primary care, is essential. The simple criteria of the Japan Atherosclerosis Society (JAS) should have superiority on this point compared with complicated scoring criteria of Dutch Lipid Clinic Network (DLCN).
Background:A substantial proportion of patients clinically diagnosed as having familial hypercholesterolemia (FH) do not manifest causative mutation(s) in the FH genes such asLDLR,APOB, andPCSK9. We ...aimed to evaluate the effect of rare and deleterious mutation(s) inABCG5/ABCG8on hyper-low-density lipoprotein (LDL) cholesterolemia in individuals who meet the clinical criteria for FH.Methods and Results:We compared the LDL cholesterol (LDL-C) values among 487 subjects with FH; the subjects were grouped according to the presence of mutation(s) in FH andABCG5/ABCG8genes. We identified 276 individuals with a deleterious mutation in 1 FH gene (57%, monogenic FH), but found no causative mutations in 156 individuals (32%, mutation-negative). A total of 37 individuals had deleterious mutations inABCG5orABCG8, but not in FH genes (8%,ABCG5/ABCG8mutation carriers). Among these, 3 individuals had sitosterolemia (0.6%) with double mutations. We also identified 18 individuals with deleterious mutations in an FH gene andABCG5orABCG8(4%,ABCG5/ABCG8-oligogenic FH). Subjects without mutations had significantly higher polygenic scores than those in any other groups. LDL-C levels in oligogenic FH subjects were significantly higher than in the monogenic FH subjects. Moreover, sitosterol/lathosterol levels were significantly affected by those mutations.Conclusions:The results suggested that rare and deleterious mutations inABCG5/ABCG8contribute substantially to mimicking and exacerbation of the FH phenotype.
Homozygous Familial Hypercholesterolemia Nohara, Atsushi; Tada, Hayato; Ogura, Masatsune ...
Journal of Atherosclerosis and Thrombosis,
07/2021, Letnik:
28, Številka:
7
Journal Article
Odprti dostop
Familial hypercholesterolemia (FH) is an inherited disorder with retarded clearance of plasma LDL caused by mutations of the genes involved in the LDL receptor-mediated pathway and most of them ...exhibit autosomal dominant inheritance. Homozygotes of FH (HoFH) may have plasma LDL-C levels, which are at least twice as high as those of heterozygous FH (HeFH) and therefore four times higher than normal levels. Prevalence of HoFH had been estimated as 1 in 1,000,000 before but more recent genetic analysis surveys predict 1 in 170,000 to 300,000. Since LDL receptor activity is severely impaired, HoFH patients do not or very poorly respond to medications to enhance activity, such as statins, and have a poorer prognosis compared to HeFH. HoFH should therefore be clinically distinguished from HeFH. Thorough family studies and genetic analysis are recommended for their accurate diagnosis.Fatal cardiovascular complications could develop even in the first decade of life for HoFH, so aggressive lipid-lowering therapy should be initiated as early as possible. Direct removal of plasma LDL by lipoprotein apheresis has been the principal measure for these patients. However, this treatment alone may not achieve stable LDL-C target levels and combination with drugs should be considered. The lipid-lowering effects of statins and PCSK9 inhibitors substantially vary depending on the remaining LDL receptor activity of individual patients. On the other hand, the action an MTP inhibitor is independent of LDL receptor activity, and it is effective in most HoFH cases.This review summarizes the key clinical issues of HoFH as well as insurance coverage available under the Japanese public healthcare system.
Sitosterolemia is a rare inherited disease characterized by increased levels of plant sterols, such as sitosterol. The cause of this disease is ATP-binding cassette (ABC) subfamily G member 5 or ...member 8 (ABCG5 or ABCG8, respectively) gene mutations. Recent advances in genetics have revealed that the prevalence of subjects with deleterious mutations in ABCG5 and/or ABCG8 genes could be more than 1 in ~200,000 individuals among the general population. Furthermore, accumulated evidence, including infantile cases exhibiting progression/regression of systemic xanthomas associated with LDL cholesterol levels, have shown that the elevation of LDL cholesterol seems to be the major cause of development of atherosclerosis and not the elevation of sitosterol. Regarding therapies, LDL apheresis, as well as proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, could be useful for sitosterolemia, in addition to ezetimibe and/or colestimide. In this study, we provide the current understanding and future perspectives of sitosterolemia, which is currently considered an extremely rare disorder but is expected to be much more prevalent in clinical settings.
Statement1. Familial hypercholesterolemia (FH) is an autosomal hereditary disease with the 3 major clinical features of hyper-LDL-cholesterolemia, premature coronary artery disease and tendon and ...skin xanthomas. As there is a considerably high risk of coronary artery disease (CAD), in addition to early diagnosis and intensive treatment, family screening (cascade screening) is required (Recommendation level A) 2. For a diagnosis of FH, at least 2 of the following criteria should be satisfied:① LDL-C ≥180 mg/dL, ② Tendon/skin xanthomas, ③ History of FH or premature CAD within 2nd degree blood relatives (Recommendation level A) 3. Intensive lipid-lowering therapy is necessary for the treatment of FH. First-line drug should be statins. (Recommendation level A, Evidence level 3) 4. Screening for CAD as well as asymptomatic atherosclerosis should be conducted periodically in FH patients. (Recommendation level A) 5. For homozygous FH, consider LDL apheresis and treatment with PCSK9 inhibitors or MTP inhibitors. (Recommendation level A) 6. For severe forms of heterozygous FH who have resistant to drug therapy, consider PCSK9 inhibitors and LDL apheresis. (Recommendation level A) 7. Refer FH homozygotes as well as heterozygotes who are resistant to drug therapy, who are children or are pregnant or have the desire to bear children to a specialist. (Recommendation level A)
This paper describes consensus statement by Joint Working Group by Japan Pediatric Society and Japan Atherosclerosis Society for Making Guidance of Pediatric Familial Hypercholesterolemia (FH) in ...order to improve prognosis of FH.FH is a common genetic disease caused by mutations in genes related to low density lipoprotein (LDL) receptor pathway. Because patients with FH have high LDL cholesterol (LDL-C) levels from the birth, atherosclerosis begins and develops during childhood which determines the prognosis. Therefore, in order to reduce their lifetime risk for cardiovascular disease, patients with FH need to be diagnosed as early as possible and appropriate treatment should be started.Diagnosis of pediatric heterozygous FH patients is made by LDL-C ≥140 mg/dL, and family history of FH or premature CAD. When the diagnosis is made, they need to improve their lifestyle including diet and exercise which sometimes are not enough to reduce LDL-C levels. For pediatric FH aged ≥10 years, pharmacotherapy needs to be considered if the LDL-C level is persistently above 180 mg/dL. Statins are the first line drugs starting from the lowest dose and are increased if necessary. The target LDL-C level should ideally be ＜140 mg/dL. Assessment of atherosclerosis is mainly performed by noninvasive methods such as ultrasound.For homozygous FH patients, the diagnosis is made by existence of skin xanthomas or tendon xanthomas from infancy, and untreated LDL-C levels are approximately twice those of heterozygous FH parents. The responsiveness to pharmacotherapy should be ascertained promptly and if the effect of treatment is not enough, LDL apheresis needs to be immediately initiated.
Background:The ODYSSEY Japan study was designed to demonstrate the reduction in low-density lipoprotein cholesterol (LDL-C) by alirocumab as add-on to existing lipid-lowering therapy in Japanese ...patients with heterozygous familial hypercholesterolemia (heFH) or non-FH at high cardiovascular risk who require additional pharmacological management to achieve their LDL-C treatment goal (<2.6 or <3.1 mmol/L, depending on risk category).Methods and Results:This randomized, double-blind, parallel-group, 52-week study was conducted in Japan. Patients (n=216) with heFH, non-FH at high cardiovascular risk with coronary disease, or classified as category III were enrolled. The prespecified safety analysis was done after the last patient completed 52 weeks. Patients were randomized (2:1, alirocumab:placebo) with stratification for heFH to s.c. alirocumab (75 mg every 2 weeks Q2 W with increase to 150 mg if week 8 LDL-C ≥2.6/3.1 mmol/L) or placebo for 52 weeks plus stable statin therapy. At week 24, mean±SE change in LDL-C from baseline was –62.5±1.3% in the alirocumab group and 1.6±1.8% in the placebo group (difference, –64.1±2.2%; P<0.0001); the reduction was sustained to week 52 (alirocumab, –62.5±1.4%; placebo, –3.6±1.9%). No patterns were evident between treatment groups for adverse events at 52 weeks.Conclusions:In high-risk Japanese patients with hypercholesterolemia on stable statin therapy, alirocumab markedly reduced LDL-C vs. placebo and was well tolerated over 52 weeks. (Circ J 2016; 80: 1980–1987)
Background:This study is aimed to compare the efficacy of the 2017 Japan Atherosclerosis Society (JAS) familial hypercholesterolemia (FH) criteria, which focuses on only 3 essential clinical ...manifestations, with that of Dutch Lipid Clinic Network (DLCN) FH criteria, which adopts a scoring system of multiple elements.Methods and Results:A total of 680 Japanese dyslipidemic participants (51% men) were enrolled between 2006 and 2018, all of whom had full evaluations of low-density lipoprotein (LDL) cholesterol, Achilles tendon X-rays, family history records, and genetic analysis of FH-associated genes (LDLR,APOB, andPCSK9). Predictive values for the existence of FH mutations by both clinical criteria were evaluated. Overall, 173 FH patients were clinically diagnosed by using the 2017 JAS criteria and 100, 57, 156, and 367 subjects were also diagnosed as having definite, probable, possible, and unlikely FH by the DLCN FH criteria, respectively. The positive and negative likelihood ratio predicting the presence of FH mutations by using the 2017 JAS FH criteria were 19.8 and 0.143, respectively; whereas, using the DLCN criteria of definite, probable, and possible FH, the ratios were 29.2 and 0.489, 9.70 and 0.332, and 3.43 and 0.040, respectively.Conclusions:Among Japanese patients, the JAS 2017 FH criteria is considered superior to diagnose FH mutation-positive patients and simultaneously rule out FH mutation-negative patients compared with the DLCN FH criteria.
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