Prospective Registry Study of Primary Dyslipidemia (PROLIPID): Rationale and Study Design

Transitional Medicine of Intractable Primary Dyslipidemias in Japan

Transitional medicine refers to the seamless continuity of medical care for patients with childhood-onset diseases as they grow into adulthood. The transition of care must be seamless in medical treatment as the patients grow and in other medical aids such as subsidies for medical expenses in the health care system. Inappropriate transitional care, either medical or social, directly causes poorer prognosis for many early-onset diseases, including primary dyslipidemia caused by genetic abnormalities. Many primary dyslipidemias are designated as intractable diseases in the Japanese health care system for specific medical aids, as having no curative treatment and requiring enormous treatment costs for lipid management and prevention of complications. However, there are problems in transitional medicine for primary dyslipidemia in Japan. As for the medical treatment system, the diagnosis rate remains low due to the shortage of specialists, their insufficient link with generalists and other field specialists, and poor linkage between pediatricians and physicians for adults. In the medical care system, there is a mismatch of diagnostic criteria of primary dyslipidemias between children and adults for medical care expense subsidization, as between The Program for the Specific Pediatric Chronic Diseases and the Program for Designated Adult Intractable Diseases. This could lead some patients subsidized in their childhood to no longer be under the coverage of the aids after transition. This review intends to describe these issues in transitional medicine of primary dyslipidemia in Japan as a part of the efforts to resolve the problems by the Committee on Primary Dyslipidemia under the Research Program on Rare and Intractable Disease of the Ministry of Health, Labour and Welfare of Japan.

The first Japanese case with familial combined hypolipidemia without any complications caused by loss-of function variants in ANGPTL3: Case report

Familial combined hypolipidemia, previously known as Familial hypobetalipoproteinemia 2 (FHBL2) is considered as an extremely rare recessive disease. Here, we present the case of familial combined hypolipidemia with homozygous loss-of function (LOF) variants in angiopoietin-like protein 3 (ANGPTL3) ((NM_014495.4) c.439_442del (p.Thr146_Asn147insTer)) using panel sequencing (46 yr male whose LDL cholesterol = 34 mg/dL). The serum level of ANGPTL3 was quite low (undetectable). Despite of extreme decreasing LDL cholesterol, this case did not have any complications as hypobetalipidemia (HBL), such as steatorrhea vomiting, hematological, neuromuscular, or ophthalmological symptoms. In addition, we did not find any systemic atherosclerosis in his carotid arteries and in coronary arteries. Based on the findings suggest that inhibition of ANGPTL3 effectively reduce LDL cholesterol without any apparent side effects, although it is still unclear if he will suffer any disadvantages because of this situation in the future.

Clinical Characteristics of Homozygous Familial Hypercholesterolemia in Japan: A Survey Using a National Database

Background

The studies evaluating patients' characteristics and lipid-lowering therapy for patients with homozygous familial hypercholesterolemia (HoFH) are scarce.

Objectives

This study aims to evaluate the characteristics of and treatments for patients with HoFH.

Methods

This study included 201 patients who were diagnosed with definite or probable HoFH from the National Database of the Japanese Ministry of Health, Labour, and Welfare.

Results

The patients' median age at diagnosis was 27 years and exhibited a bimodal distribution. Approximately 70% of patients had coronary artery disease. Regarding genetic backgrounds, mutations in the low-density lipoprotein (LDL) receptor (LDLR) were identified in most of the patients, followed by proprotein convertase subtilisin/kexin type 9 (PCSK9) and double heterozygotes of LDLR. High-intensity statins were introduced to 74% of the patients, lipoprotein apheresis was performed in 21%, and PCSK9 inhibitors were administered to 50%. The mean of LDL cholesterol before and after treatment were 10.1 mmol/L and 3.9 mmol/L, respectively. Patients with coronary artery disease had significantly decreased LDL cholesterol. A quarter of the patients (n = 49, 24%) exhibited valvular diseases, particularly aortic valvular disease (n = 34, 61%).

Conclusions

The national epidemiological study of patients with HoFH showed patient's clinical and genetic characteristics and LDL-lowering therapy in Japan. There was considerable diversity in the severity of phenotypes, including LDL cholesterol levels, among patients with HoFH. In Japan, the management of LDL cholesterol in HoFH is still inadequate despite the availability of intensive lipid-lowering therapies.

A case of cerebrotendinous xanthomatosis with massive xanthomas but without a considerable increase in serum cholestanol levels

Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disorder caused by mutations in the sterol 27-hydroxylase gene (CYP27A1). Due to the deficiency of 27-hydroxylase, the synthesis of bile acids from cholesterol is impaired and excessive cholestanol accumulates in various tissues, such as the central nervous system, tendons, and lenses. Patients with CTX typically manifest intellectual decline, pyramidal tract symptoms, cerebellar symptoms, tendon xanthomas, juvenile cataracts, neonatal jaundice, chronic diarrhea, osteoporosis, and premature cardiovascular disease. Here, we report the atypical case of a 35-year-old female with CTX having massive xanthomas but without a considerable increase in serum cholestanol levels (3.9 µg/mL). In the differential diagnosis of xanthoma, CTX should not be ruled out even if the serum levels of cholestanol are not high, and genetic testing is necessary to make the appropriate diagnosis.

2023 Update on European Atherosclerosis Society Consensus Statement on Homozygous Familial Hypercholesterolaemia: new treatments and clinical guidance

This 2023 statement updates clinical guidance for homozygous familial hypercholesterolaemia (HoFH), explains the genetic complexity, and provides pragmatic recommendations to address inequities in HoFH care worldwide. Key strengths include updated criteria for the clinical diagnosis of HoFH and the recommendation to prioritize phenotypic features over genotype. Thus, a low-density lipoprotein cholesterol (LDL-C) >10 mmol/L (>400 mg/dL) is suggestive of HoFH and warrants further evaluation. The statement also provides state-of-the art discussion and guidance to clinicians for interpreting the results of genetic testing and for family planning and pregnancy. Therapeutic decisions are based on the LDL-C level. Combination LDL-C-lowering therapy-both pharmacologic intervention and lipoprotein apheresis (LA)-is foundational. Addition of novel, efficacious therapies (i.e. inhibitors of proprotein convertase subtilisin/kexin type 9, followed by evinacumab and/or lomitapide) offers potential to attain LDL-C goal or reduce the need for LA. To improve HoFH care around the world, the statement recommends the creation of national screening programmes, education to improve awareness, and management guidelines that account for the local realities of care, including access to specialist centres, treatments, and cost. This updated statement provides guidance that is crucial to early diagnosis, better care, and improved cardiovascular health for patients with HoFH worldwide.