Difference in the risk factors for coronary, renal and other peripheral arteriosclerosis in heterozygous familial hypercholesterolemia

Comorbidities with Familial Hypercholesterolemia (FH): A Systematic Review

Familial hypercholesterolemia (FH) is linked to high levels of low-density lipoprotein cholesterol (LDL-C), atherosclerotic, and aortic stenosis to a lesser extent. We looked at the incidence of prevalent comorbid disorders other than cardiovascular disease (CVD), such as diabetes, chronic kidney disease (CKD), hypertension, and cancer in heterozygous FH (HeFH) patients. PubMed, Web of Science, and Google Scholar were searched systematically for studies reporting comorbidities in FH patients. Finally, 23 studies were included after excluding duplicates, papers with unrelated titles, reviews, abstracts, and papers with not sufficient data. Results showed that among the comorbidities that have been studied; FH patients had a greater prevalence of CKD. In terms of diabetes, the data are inconsistent, with some research indicating a higher prevalence of diabetes in FH patients and mostly indicating the opposite. Polymorphism study showed that hypertension has been linked to FH; however, the prevalence of the hypertensive subjects varies among FH groups. In comparison to the general population, cancer was found to have a lower or similar prevalence in FH patients. More research is needed in this area due to the variability of the results of the relationship between diabetes and FH and the small number of studies on cancer. In conclusion only CKD can be considered as an important and prevalent comorbidity in FH population after CVDs.

LDL-Cholesterol versus Glucose in Microvascular and Macrovascular Disease

BACKGROUND

The causal relationships between increased concentrations of low density lipoprotein (LDL)-cholesterol and glucose and risk of ischemic heart disease are well established. The causal contributions of LDL-cholesterol and glucose to risk of peripheral micro- and macrovascular diseases are less studied, especially in prediabetic stages and in a general population setting.

CONTENT

This review summarizes the current evidence for a causal contribution of LDL-cholesterol and glucose to risk of a spectrum of peripheral micro- and macrovascular diseases and reviews possible underlying disease mechanisms, including differences between vascular compartments, and finally discusses the clinical implications of these findings, including strategies for prevention and treatment.

SUMMARY

Combined lines of evidence suggest that LDL-cholesterol has a causal effect on risk of peripheral arterial disease and chronic kidney disease, both of which represent manifestations of macrovascular disease due to atherosclerosis and accumulation of LDL particles in the arterial wall. In contrast, there is limited evidence for a causal effect on risk of microvascular disease. Glucose has a causal effect on risk of both micro- and macrovascular disease. However, most evidence is derived from studies of individuals with diabetes. Further studies in normoglycemic and prediabetic individuals are warranted. Overall, LDL-cholesterol-lowering reduces risk of macrovascular disease, while evidence for a reduction in risk of microvascular disease is inconsistent. Glucose-lowering has a beneficial effect on risk of microvascular diseases and on risk of chronic kidney disease and estimated glomerular filtration rate (eGFR) in some studies, while results on risk of peripheral arterial disease are conflicting.

Non-coronary atherosclerotic cardiovascular disease in patients with familial hypercholesterolaemia

Objective: Familial hypercholesterolaemia (FH) is a common autosomal dominant inherited disease, affecting 1 in 200-500 individuals worldwide. FH is characterized by elevated circulating low-density lipoprotein cholesterol (LDL-C) concentrations. Its association with increased risk of coronary heart disease (CHD) (>10-fold, compared with patients without FH) is well documented. However, the association between FH and non-CHD atherosclerotic cardiovascular disease (ASCVD) risk has been poorly documented.Methods: PubMed was searched for English language publications regarding the association between FH and carotid artery stenosis, stroke, peripheral artery disease (PAD; lower limbs and other arterial beds), aortic valve calcification (AoVC), aortic and renal artery disease, chronic kidney disease, atrial fibrillation and heart failure, from conception until 22 December 2019.Results: Despite the small number of available studies, as well as their characteristics (sample size, diagnostic criteria used, retrospective or cross-sectional design), there is evidence for a positive association between FH and stroke, PAD or AoVC. More data are needed for definitive conclusions regarding aortic and renal artery disease, chronic kidney disease, atrial fibrillation and heart failure. There is paucity of data with respect to homozygous FH. Increased lipoprotein (a) concentrations, often seen in FH patients, may also contribute to this non-CHD atherosclerotic process. A key question is whether statins or other LDL-C-lowering therapies, provide an additional reduction in the risk of these less-recognized vascular and non-vascular complications in FH patients.Conclusions: Heterozygous FH is associated with increased risk for stroke, PAD and AoVC. Clinicians should take these non-CHD ASCVD aspects into consideration for optimal management of FH patients.

Familial Hypercholesterolemia and Risk of Peripheral Arterial Disease and Chronic Kidney Disease

CONTEXT

Individuals with familial hypercholesterolemia (FH) have a high risk of coronary artery disease, but their risk of peripheral arterial disease (PAD) and chronic kidney disease (CKD) is unknown.

OBJECTIVE

In individuals with clinical FH, we tested the hypotheses (1) that the risks of PAD and CKD are elevated and (2) that low ankle-brachial index (ABI) and estimated glomerular filtration rate (eGFR) are associated with a high risk of myocardial infarction.

DESIGN AND SETTING

Prospective cohort study of the general population.

PARTICIPANTS

A total of 106,172 individuals, of whom 7109 were diagnosed with FH.

MAIN OUTCOME MEASURES

PAD, CKD, and myocardial infarction.

RESULTS

Compared with individuals with unlikely FH, multivariable adjusted ORs (95% CIs) of PAD were 1.84 (1.70 to 2.00) in those with possible FH and 1.36 (1.00 to 1.84) in individuals with probable/definite FH. For CKD, the corresponding ORs (95% CIs) were 1.92 (1.78 to 2.07) and 2.42 (1.86 to 3.26). Compared with individuals with unlikely FH and ABI >0.9, the multivariable adjusted hazard ratio (95% CI) of myocardial infarction was 4.60 (2.36 to 8.97) in those with possible/probable/definite FH and ABI ≤0.9. Compared with individuals with unlikely FH and eGFR ≥60 mL/min/1.73 m2, the corresponding value was 2.19 (1.71 to 2.82) in those with possible/probable/definite FH and eGFR <60 mL/min/1.73 m2.

CONCLUSIONS

Individuals with clinical FH have increased risks of PAD and CKD, and low ABI and eGFR are associated with high risk of myocardial infarction. Consequently, individuals with FH should be screened for PAD and CKD, and ABI and eGFR may be used as prognostic tools in the management and treatment of FH to identify those at very high risk of myocardial infarction.

Plasma Heme Oxygenase-1 Levels in Patients with Coronary and Peripheral Artery Diseases

Aims

Heme oxygenase-1 (HO-1) is an intracellular enzyme that catalyzes the oxidation of heme to generate CO, biliverdin, and iron. Since these products have antiatherogenic properties, HO-1 may play a protective role against the progression of atherosclerosis. However, plasma HO-1 levels in patients with atherosclerotic diseases, such as coronary artery disease (CAD) and peripheral artery disease (PAD), have not been clarified yet.

Methods

We investigated plasma HO-1 levels by ELISA in 410 consecutive patients undergoing elective coronary angiography who also had an ankle-brachial index (ABI) test for PAD screening.

Results

Of the 410 study patients, CAD was present in 225 patients (55%) (1-vessel (1-VD), n = 91; 2-vessel (2-VD), n = 66; 3-vessel disease (3-VD), n = 68). PAD (ABI < 0.9) was found in 36 (9%) patients. Plasma HO-1 levels did not differ between 225 patients with CAD and 185 without CAD (median 0.44 versus 0.35 ng/mL), but they were significantly lower in 36 patients with PAD than in 374 without PAD (0.27 versus 0.41 ng/mL, P < 0.02). After excluding the 36 patients with PAD, HO-1 levels were significantly higher in 192 patients with CAD than in 182 without CAD (0.45 versus 0.35 ng/mL, P < 0.05). HO-1 levels in 4 groups of CAD(−), 1-VD, 2-VD, and 3-VD were 0.35, 0.49, 0.44, and 0.44 ng/mL, respectively, and were highest in 1-VD (P < 0.05). In the multivariate analysis, HO-1 levels were inversely associated with PAD, whereas they were also associated with CAD. The odds ratios for PAD and CAD were 2.12 (95% CI = 1.03–4.37) and 0.65 (95% CI = 0.42–0.99) for the HO-1 level of <0.35 ng/mL, respectively.

Conclusions

Plasma HO-1 levels were found to be low in patients with PAD, in contrast to high levels in patients with CAD.

Guidelines for Diagnosis and Treatment of Familial Hypercholesterolemia 2017

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).

Prominent Tendon Xanthomas and Abdominal Aortic Aneurysm Associated with Cerebrotendinous Xanthomatosis Identified Using Whole Exome Sequencing

A 63-year-old man was hospitalized due to an abdominal pulsatile mass. Computed tomography revealed a saccular type abdominal aortic aneurysm, the diameter of which was 52 mm. A physical examination revealed prominent Achilles tendon thickness and plantar xanthomas. He was born in a family of consanguineous marriage, where his parents were second cousins. He had no familial history of high low-density lipoprotein cholesterol, tendon xanthomas, or premature atherosclerosis. Whole-exome sequencing assuming recessive inheritance determined his genetic diagnosis to be cerebrotendinous xanthomatosis caused by homozygous mutations (c.410G>A or p.Arg137Gln) in the cytochrome P450 subfamily 27 A1 (CYP27A1) gene.

Prominent Tendon Xanthomas and Abdominal Aortic Aneurysm Associated with Cerebrotendinous Xanthomatosis Identified Using Whole Exome Sequencing

A 63-year-old man was hospitalized due to an abdominal pulsatile mass. Computed tomography revealed a saccular type abdominal aortic aneurysm, the diameter of which was 52 mm. A physical examination revealed prominent Achilles tendon thickness and plantar xanthomas. He was born in a family of consanguineous marriage, where his parents were second cousins. He had no familial history of high low-density lipoprotein cholesterol, tendon xanthomas, or premature atherosclerosis. Whole-exome sequencing assuming recessive inheritance determined his genetic diagnosis to be cerebrotendinous xanthomatosis caused by homozygous mutations (c.410G>A or p.Arg137Gln) in the cytochrome P450 subfamily 27 A1 (CYP27A1) gene.

Characteristics and Vascular Complications of Familial Hypercholesterolemia in Korea

Familial hypercholesterolemia (FH) is presently an important health issue worldwide. This condition shows phenotypic and genetic variations among affected people, and clinical and genetic data on FH are critical for effective diagnosis and management. Korean FH patients have relatively low levels of cholesterol and prevalence of xanthoma than patients from other countries, as determined by previous studies. The best predictive value of low-density lipoprotein cholesterol (LDL-C) for pathogenic mutations is suggested as 225 mg/dL. Many known and novel mutations on LDLR and some on APOB or PCSK9 have been identified in one-third of clinically diagnosed probands, and their locations on genes varied. Coronary artery disease was reported in 28% Korean FH patients, and traditional cardiovascular risk factors were associated with this complication. Aortic valve changes were also prevalent. However, the achievement rate of LDL-C target using lipid-lowering therapy is not satisfactory and is only 21%-44%. A further expanded registry and additional analysis may provide a more useful clinical tool for the diagnosis and treatment of Korean FH patients.

Guidelines for the management of familial hypercholesterolemia

Familial hypercholesterolemia (FH) is a highly prevalent autosomal dominant hereditary disease, generally characterized by three major signs, hyper-low-density-lipoprotein (LDL) cholesterolemia, tendon/skin xanthomas and premature coronary artery disease (CAD). Because the risk of CAD is very high in these patients, they should be identified at an early stage of their lives and started on intensive treatment to control LDL-cholesterol. We here introduce a new guideline for the management of FH patients in Japan intending to achieve better control to prevent CAD. Diagnostic criteria for heterozygous FH are 2 or more of 1) LDL-cholesterol ≥180 mg/dL, 2) tendon/skin xanthoma(s), and 3) family history of FH or premature CAD within second degree relatives, for adults; and to have both 1) LDL-cholesterol ≥140 mg/dL and 2) family history of FH or premature CAD within second degree relatives, for children. For the treatment of adult heterozygous FH, intensive lipid control with statins and other drugs is necessary. Other risks of CAD, such as smoking, diabetes mellitus, hypertension etc., should also be controlled strictly. Atherosclerosis in coronary, carotid, or peripheral arteries, the aorta and aortic valve should be screened periodically. FH in children, pregnant women, and women who wish to bear a child should be referred to specialists. For homozygotes and severe heterozygotes resistant to drug therapies, LDL apheresis should be performed. The treatment cost of homozygous FH is authorized to be covered under the program of Research on Measures against Intractable Diseases by the Japanese Ministry of Health, Labour, and Welfare.

Defining patients at extremely high risk for coronary artery disease in heterozygous familial hypercholesterolemia

AIM

Heterozygous patients with familial hypercholesterolemia (FH) are known to be associated with a high risk of coronary artery disease (CAD), which is a major determinant of their clinical outcome. The prognosis of heterozygous FH patients substantially varies, being dependent on the level of their CAD risk, and their therapeutic regimen should be individualized. We assessed critical levels of LDL-cholesterol (LDL-C) and Achilles tendon thickness (ATT) to identify heterozygous FH patients at "very high" risk for CAD.

METHODS

One hundred and nine heterozygous FH patients who had no history of CAD and had had their plasma lipid profile and ATT assessed before treatment were followed up until their first CAD event or 31 December 2010. Multivariable logistic regression models were used to analyze the correlation of LDL-C and/or ATT levels with the risk of developing CAD.

RESULTS

During the follow-up period, 21 of the 109 patients had a CAD event, diagnosed by coronary angiogram. Individuals in the highest tertile of LDL-C had a CAD risk 8.29-fold higher than those in the lowest tertile. Individuals in the highest tertile of the ATT group had a 7.82-fold higher CAD risk than those in the lowest tertile. Those who had either LDL-C ≥ 260 mg/dL or ATT ≥ 14.5 had a 23.94-fold higher CAD risk than those with LDL-C < 260 mg/dL and ATT <14.5 mm.

CONCLUSIONS

In heterozygous FH patients, LDL-C 260 mg/dL or higher and/or ATT 14.5 mm or thicker are useful markers for extracting patients at "very high" risk for CAD.

Significant relationship between changes in brachial-ankle pulse wave velocity relative to blood pressure elevation and coronary artery disease

OBJECTIVES

Based on well-established physiological theories, we studied correlations between changes in brachial-ankle pulse wave velocity (baPWV) relative to blood pressure (BP) elevation (elasticity of large-to-medium-sized arteries), and coronary artery disease (CAD).

METHODS

The baPWV (in centimeters/second) and BP (in millimeters of mercury) were determined in 101 patients before, during, and/or after a cold pressor test using a volume-plethysmographic system.

RESULTS

Significantly higher rates of increase in PWV relative to changes in BP were observed in the CAD(+) group than in the CAD(-) group when mean BP [median (25th-75th percentiles): 14.8 (8.3-24.9) vs. 8.6 (5.7-11.4) cm/s/mmHg, P<0.0001], and systolic [10.1 (6.0-17.5) vs. 6.4 (4.4-10.6) cm/s/mmHg, P=0.0023] and diastolic BP [21.0 (14.0-34.4) vs. 10.8 (6.8-16.1) cm/s/mmHg, P<0.0001] were used as BP indices. Similarly, the rates of increase in baPWV showed a significant correlation with the extent of CAD. The rate of increase in baPWV obtained using the mean, systolic and diastolic BP as indices showed an area under the receiver operating characteristic curve of 0.68-0.76, sensitivity of 65-75%, and specificity of 65-75% for the detection of CAD. The area under the receiver operating characteristic curve, sensitivity, and specificity for the rate of increase were slightly higher than those for baseline baPWV and baseline baPWV/baseline BP ratio, but not to a significant degree.

CONCLUSION

The rate of increase in baPWV relative to BP elevation determined by cold pressor test is significantly and moderately correlated with CAD. To identify patients with CAD, the rate of increase in baPWV relative to changes in BP can provide considerable, but limited, information.

A case of homozygous familial hypercholesterolemia with focal segmental glomerulosclerosis

Familial hypercholesterolemia (FH) is a common autosomal dominant inherited disorder characterized by increased levels of circulating plasma low-density lipoprotein cholesterol (LDL-C), tendon xanthomas, and premature atherosclerotic cardiovascular disease. Homozygous FH occurs in only one in a million people. Focal segmental glomerulosclerosis (FSGS) is clinically characterized by proteinuria, which is marked in the majority of cases and accompanied by nephrotic syndrome, high incidence of hypertension, and progression to renal failure. To our knowledge, we herein report for the first time a case of homozygous FH associated with FSGS. A seven-and-a-half-year-old boy was referred to our hospital due to cutaneous xanthomata and growth retardation. He had multiple nodular yellowish cutaneous xanthomatous lesions each 1 cm in size over his knees and sacral region. Laboratory data included cholesterol level of 1,050 mg/dl, low density lipoprotein cholesterol (LDL-C) 951 mg/dl, high-density lipoprotein cholesterol (HDL-C) 29 mg/dl, triglycerides 168 mg/dl, total protein 6.3 g/dl, and albumin 3.2 g/dl. Urinary protein excretion was 78 mg/m(2) per hour. A percutaneous renal biopsy was performed, and histological findings showed FSGS. Treatment with cholestyramine and atorvastatin was unsuccessful in terms of lowering lipids, and he was placed on weekly sessions of plasmapheresis. Total cholesterol was reduced from 1,050 mg/dl to 223 mg/dl, LDL-C from 951 mg/dl to 171 mg/dl, and urinary protein excretion from 78 mg/m(2) per hour to 42 mg/m(2) per hour after eight sessions of plasmapheresis. It is our belief that plasmapheresis is a treatment of choice in patients with FSGS associated with FH.

Premature cardiovascular disease in young women with heterozygous familial hypercholesterolemia

Heterozygous familial hypercholesterolemia is associated with elevated low-density lipoprotein cholesterol levels and the development of premature cardiovascular disease. Despite this general statement, data regarding the incidence of cardiovascular disease in young women with familial hypercholesterolemia are lacking. In this review, information of age-specific incidence, risk factors and therapeutic avenues in women with heterozygous familial hypercholesterolemia are discussed.

Differences in Risk Factors for Lower Extremity Arterial Occlusive Disease

BACKGROUND

Patients undergoing lower extremity revascularization have associated cardiovascular risks: smoking, hypertension, dyslipidemia, and diabetes. This study evaluated the impact of cardiovascular risk factors on proximal versus distal arterial occlusive disease in patients undergoing lower extremity revascularization as adjusted to a control group without vascular disease.

STUDY DESIGN

We performed a retrospective, case-control study that included 151 patients undergoing lower extremity revascularization and 229 patients undergoing knee and hip replacement (controls). Risk factors were determined for each of three separate groups undergoing revascularization for different levels of occlusive disease: aortoiliac, superficial femoral, and popliteal-tibial. Comparisons to controls were tested using t-tests or chi-square tests and multiple logistic regression.

RESULTS

Dyslipidemia was associated with a significant risk of aortoiliac (odds ratio [OR]=3.4; p=0.0006) and superficial femoral occlusion (OR=2.8; p=0.01) but was less strongly associated with popliteal-tibial occlusion (OR=2.1; p=0.09). Smoking was strongly associated with aortoiliac (OR=4.5; p=0.004) and superficial femoral disease (OR=4.6; p=0.0007) but not popliteal-tibial disease (OR=1.3; p=0.53). In contrast, diabetes mellitus and chronic renal insufficiency were strong risk factors for popliteal-tibial occlusion (OR=5.4, p=0.0002; OR=3.9, p=0.01, respectively), but were not significant risk factors for aortoiliac or superficial femoral occlusion.

CONCLUSIONS

These data, which use revascularization level as a surrogate marker for lower extremity arterial disease, suggest that the risk factor profile for proximal disease differs from that of distal disease. These findings may reflect differences in the biology of disease and indicate that different risk factors have various anatomic influences on arterial disease formation.

Efficacy of Colestimide Coadministered With Atorvastatin in Japanese Patients With Heterozygous Familial Hypercholesterolemia (FH)

BACKGROUND

Colestimide, a 2-methylimidazole-epichlorohydrin polymer, is a new bile-acid-sequestering resin, that is 4-fold as powerful at lowering low-density lipoprotein cholesterol (LDL-C) as the conventional resin (cholestyramine). Moreover, colestimide has excellent patient compliance because it is available in tablet form.

METHODS AND RESULTS

The clinical efficacy of colestimide coadministered with atorvastatin on lipid and apolipoprotein concentrations was examined in 15 patients (M/F=10/5, mean+/-SE age=54+/-9 years) with heterozygous familial hypercholesterolemia (FH). After a period of wash-out of any lipid-lowering drugs, atorvastatin (20-40 mg) was administered to patients for at least 8 weeks, and then 3 g of colestimide was administered for a further 8 weeks. Total and LDL-C significantly (<0.0001) decreased by 35% from 361 to 233 mg/dl and 41% from 274 to 161 mg/dl, respectively. Addition of colestimide caused a further significant 12% and 20% reduction, respectively, from the initial values to 205 and 129 mg/dl, respectively. Colestimide was also effective in reducing serum LDL-C concentrations in heterozygous FH patients with hypertriglyceridemia (triglycerides>or=150 mg/dl).

CONCLUSIONS

When monotherapy with atorvastatin is insufficient to treat severely hypercholesterolemic patients, such as those with heterozygous FH, colestimide acts to reinforce the action of statins.