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1.
Int J Mol Sci ; 23(16)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36012410

RESUMO

For almost a century, familial hypercholesterolemia (FH) has been considered a serious disease, causing atherosclerosis, cardiovascular disease, and ischemic stroke. Closely related to this is the widespread acceptance that its cause is greatly increased low-density-lipoprotein cholesterol (LDL-C). However, numerous observations and experiments in this field are in conflict with Bradford Hill's criteria for causality. For instance, those with FH demonstrate no association between LDL-C and the degree of atherosclerosis; coronary artery calcium (CAC) shows no or an inverse association with LDL-C, and on average, the life span of those with FH is about the same as the surrounding population. Furthermore, no controlled, randomized cholesterol-lowering trial restricted to those with FH has demonstrated a positive outcome. On the other hand, a number of studies suggest that increased thrombogenic factors-either procoagulant or those that lead to high platelet reactivity-may be the primary risk factors in FH. Those individuals who die prematurely have either higher lipoprotein (a) (Lp(a)), higher factor VIII and/or higher fibrinogen compared with those with a normal lifespan, whereas their LDL-C does not differ. Conclusions: Many observational and experimental studies have demonstrated that high LDL-C cannot be the cause of premature cardiovascular mortality among people with FH. The number who die early is also much smaller than expected. Apparently, some individuals with FH may have inherited other, more important risk factors than a high LDL-C. In accordance with this, our review has shown that increased coagulation factors are the commonest cause, but there may be other ones as well.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Hiperlipoproteinemia Tipo II , Fatores de Coagulação Sanguínea , LDL-Colesterol , Humanos , Hiperlipoproteinemia Tipo II/complicações , Lipoproteína(a) , Fatores de Risco
5.
Expert Rev Clin Pharmacol ; 14(3): 405-406, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33565344

RESUMO

Recently, Polychronopoulos and Tziomalos reviewed research on the use of inclisiran and bempedoic acid in the management of cardiovascular disease (CVD) risk in people with familial hypercholesterolemia (FH). Their treatment recommendations were based on the general premise that high LDL-cholesterol (LDL-C) is inherently atherogenic, and that low levels of LDL-C need to be achieved to reduce CVD risk in FH individuals. However, their perspective on LDL-C is flawed at two levels of analysis: 1) They ignored the extensive literature demonstrating that CVD is not caused by high LDL-C; and 2) they failed to consider CVD treatment strategies that take into account the extensive literature that has shown that coagulation factors are more closely related to coronary events in FH than is LDL-C. In the following, we have briefly addressed each of these flaws in their review.


Assuntos
Doenças Cardiovasculares , Hipercolesterolemia , Hiperlipoproteinemia Tipo II , LDL-Colesterol , Humanos , Fatores de Risco
6.
BMJ Evid Based Med ; 26(6): 295-301, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-32631832

RESUMO

We have evaluated dietary recommendations for people diagnosed with familial hypercholesterolaemia (FH), a genetic condition in which increased low-density lipoprotein cholesterol (LDL-C) is associated with an increased risk for coronary heart disease (CHD). Recommendations for FH individuals have emphasised a low saturated fat, low cholesterol diet to reduce their LDL-C levels. The basis of this recommendation is the 'diet-heart hypothesis', which postulates that consumption of food rich in saturated fat increases serum cholesterol levels, which increases risk of CHD. We have challenged the rationale for FH dietary recommendations based on the absence of support for the diet-heart hypothesis, and the lack of evidence that a low saturated fat, low cholesterol diet reduces coronary events in FH individuals. As an alternative approach, we have summarised research which has shown that the subset of FH individuals that develop CHD exhibit risk factors associated with an insulin-resistant phenotype (elevated triglycerides, blood glucose, haemoglobin A1c (HbA1c), obesity, hyperinsulinaemia, high-sensitivity C reactive protein, hypertension) or increased susceptibility to develop coagulopathy. The insulin-resistant phenotype, also referred to as the metabolic syndrome, manifests as carbohydrate intolerance, which is most effectively managed by a low carbohydrate diet (LCD). Therefore, we propose that FH individuals with signs of insulin resistance should be made aware of the benefits of an LCD. Our assessment of the literature provides the rationale for clinical trials to be conducted to determine if an LCD would prove to be effective in reducing the incidence of coronary events in FH individuals which exhibit an insulin-resistant phenotype or hypercoagulation risk.


Assuntos
Doença das Coronárias , Hiperlipoproteinemia Tipo II , LDL-Colesterol , Doença das Coronárias/prevenção & controle , Dieta , Humanos
7.
Expert Rev Clin Pharmacol ; 13(12): 1289-1294, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33416003

RESUMO

Introduction: The European Society of Cardiology and European Atherosclerosis Society (ESC/EAS) have recently published three major revisions of their guidelines for the management of chronic heart disease, blood lipids, and diabetes. Areas covered: We have scrutinized these guidelines in detail and found that the authors have ignored many studies that are in conflict with their conclusions and recommendations. Expert commentary: The authors of the guidelines have ignored that LDL-cholesterol (LDL-C) of patients with acute myocardial infarction is lower than normal; that high cholesterol is not a risk factor for diabetics; that the degree of coronary artery calcification is not associated with LDL-C; and that 27 follow-up studies have shown that people with high total cholesterol or LDL-C live just as long or longer than people with low cholesterol. They have also ignored the lack of exposure-response in the statin trials; that several of these trials have been unable to lower CVD or total mortality; that no statin trial has succeeded with lowering mortality in women, elderly people, or diabetics; and that cholesterol-lowering with statins has been associated with many serious side effects.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Colesterol/sangue , Guias de Prática Clínica como Assunto/normas , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/efeitos adversos , Doenças Cardiovasculares/etiologia , LDL-Colesterol/sangue , Europa (Continente) , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Hipercolesterolemia/complicações , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , Fatores de Risco
8.
PLoS One ; 14(1): e0205138, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30653537

RESUMO

Statins have been prescribed for primary prevention of cardiovascular disease (CVD) for nearly 3 decades. Throughout this period key opinion leaders in the field have been dismayed by the high rate of non-adherence of patients to follow their statin regimen. Hope et al., [1] have addressed this issue by providing a systematic review of research on predictors of statin adherence for primary prevention of CVD. However, their review does not address the ongoing debate as to whether statin treatment is warranted for primary prevention of CVD, nor does it adequately address concerns regarding adverse effects of statins. We have therefore written a commentary which provides a broader perspective on the benefits versus harms of statin therapy. Our perspective of the literature is that non-adherence to statin treatment for primary prevention of CVD is justified because the meager benefits are more than offset by the extensive harms.


Assuntos
Doenças Cardiovasculares , Inibidores de Hidroximetilglutaril-CoA Redutases , Humanos , Prevenção Primária
9.
Scand Cardiovasc J ; 42(4): 236-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18615352

RESUMO

Most researchers to-day consider that a high intake of saturated fat and elevated LDL cholesterol are the most important causes of atherosclerosis and coronary heart disease. The lipid hypothesis has dominated cardiovascular research and prevention for almost half a century although the number of contradictory studies may exceed those that are supportive. The harmful influence of a campaign that ignores much of the science extends to medical research, health care, food production and human life. There is an urgent need to draw attention to the most striking contradictions, many of which may be unknown to most doctors and researchers.


Assuntos
Aterosclerose/etiologia , Aterosclerose/prevenção & controle , LDL-Colesterol/efeitos adversos , Doença das Coronárias/prevenção & controle , Ácidos Graxos/efeitos adversos , LDL-Colesterol/sangue , Ácidos Graxos/sangue , Humanos
10.
Med Hypotheses ; 121: 60-63, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30396495

RESUMO

High low-density-lipoprotein cholesterol (LDL-C) is routinely described as the main cause of cardiovascular disease (CVD) in familial hypercholesterolemia (FH). However, numerous observations are in conflict with Bradford Hill's criteria for causality: a) degree of atherosclerosis is not associated with LDL-C; b) on average the life span of people with FH is about the same as for other people; c) LDL-C of people with FH without CVD is almost as high as in FH patients of the same age with CVD; and d) questionable benefit or none at all have been achieved in the controlled, randomized cholesterol-lowering trials that have included FH individuals only. Obviously, those individuals with FH who suffer from CVD may have inherited other and more important risk factors of CVD than high LDL-C. In accordance, several studies of FH individuals have shown that various coagulation factors may cause CVD. Equally, some non-FH members of an FH kindred with early CVD, have been found to suffer from early CVD as well. Cholesterol-lowering has only been successful in an animal experiment by using probucol, which has anticoagulant effects as well. We conclude that systematic studies of all kinds of risk factors among FH individuals are urgently required, because today millions of people with FH are treated with statins, the benefit of which in FH is unproven, and which have many serious side effects. We predict that treatment of FH individuals with elevated coagulation factors with anticoagulative drugs is more effective than statin treatment alone.


Assuntos
Fatores de Coagulação Sanguínea/metabolismo , Doenças Cardiovasculares/sangue , LDL-Colesterol/sangue , Hiperlipoproteinemia Tipo II/sangue , Adolescente , Adulto , Idoso , Animais , Anticolesterolemiantes/uso terapêutico , Anticoagulantes , Aterosclerose/complicações , Coagulação Sanguínea , Doenças Cardiovasculares/metabolismo , Criança , Pré-Escolar , Feminino , Fibrinolíticos/farmacologia , Homozigoto , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
11.
Expert Rev Clin Pharmacol ; 11(10): 959-970, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30198808

RESUMO

INTRODUCTION: For half a century, a high level of total cholesterol (TC) or low-density lipoprotein cholesterol (LDL-C) has been considered to be the major cause of atherosclerosis and cardiovascular disease (CVD), and statin treatment has been widely promoted for cardiovascular prevention. However, there is an increasing understanding that the mechanisms are more complicated and that statin treatment, in particular when used as primary prevention, is of doubtful benefit. Areas covered: The authors of three large reviews recently published by statin advocates have attempted to validate the current dogma. This article delineates the serious errors in these three reviews as well as other obvious falsifications of the cholesterol hypothesis. Expert commentary: Our search for falsifications of the cholesterol hypothesis confirms that it is unable to satisfy any of the Bradford Hill criteria for causality and that the conclusions of the authors of the three reviews are based on misleading statistics, exclusion of unsuccessful trials and by ignoring numerous contradictory observations.


Assuntos
Doenças Cardiovasculares/prevenção & controle , LDL-Colesterol/sangue , Hipercolesterolemia/complicações , Aterosclerose/etiologia , Aterosclerose/prevenção & controle , Doenças Cardiovasculares/etiologia , Colesterol/sangue , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Prevenção Primária/métodos , Fatores de Risco
14.
Expert Rev Clin Pharmacol ; 10(12): 1411-1412, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-26496064

RESUMO

Response to: Ferenci T. Absolute risk reduction may depend on the duration of the follow-up. Expert Rev Clin Pharmacol. 2017;10(12):1409-1410.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Enganação , Seguimentos , Humanos , Números Necessários para Tratar , Pesquisa
17.
BMJ Open ; 6(6): e010401, 2016 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-27292972

RESUMO

OBJECTIVE: It is well known that total cholesterol becomes less of a risk factor or not at all for all-cause and cardiovascular (CV) mortality with increasing age, but as little is known as to whether low-density lipoprotein cholesterol (LDL-C), one component of total cholesterol, is associated with mortality in the elderly, we decided to investigate this issue. SETTING, PARTICIPANTS AND OUTCOME MEASURES: We sought PubMed for cohort studies, where LDL-C had been investigated as a risk factor for all-cause and/or CV mortality in individuals ≥60 years from the general population. RESULTS: We identified 19 cohort studies including 30 cohorts with a total of 68 094 elderly people, where all-cause mortality was recorded in 28 cohorts and CV mortality in 9 cohorts. Inverse association between all-cause mortality and LDL-C was seen in 16 cohorts (in 14 with statistical significance) representing 92% of the number of participants, where this association was recorded. In the rest, no association was found. In two cohorts, CV mortality was highest in the lowest LDL-C quartile and with statistical significance; in seven cohorts, no association was found. CONCLUSIONS: High LDL-C is inversely associated with mortality in most people over 60 years. This finding is inconsistent with the cholesterol hypothesis (ie, that cholesterol, particularly LDL-C, is inherently atherogenic). Since elderly people with high LDL-C live as long or longer than those with low LDL-C, our analysis provides reason to question the validity of the cholesterol hypothesis. Moreover, our study provides the rationale for a re-evaluation of guidelines recommending pharmacological reduction of LDL-C in the elderly as a component of cardiovascular disease prevention strategies.


Assuntos
Doenças Cardiovasculares/mortalidade , LDL-Colesterol/sangue , Mortalidade , Idoso , Humanos , Pessoa de Meia-Idade , Fatores de Risco
18.
BMC Nephrol ; 6: 15, 2005 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-16354301

RESUMO

BACKGROUND: Much epidemiological evidence suggests that hydrocarbon exposure may induce glomerulonephritis and worsen its course in many patients. The mechanisms are unknown, however, no specific microscopic pattern has been identified, and it has also been argued that hydrocarbon exposure causes tubular damage mainly. Studying experimental animals may best answer these questions, and as no systematic review of glomerulonephritis produced experimentally by hydrocarbon exposure has been performed previously, I found it relevant to search for and analyse such studies. METHODS: Animal experiments having mimicked human glomerulonephritis by hydrocarbon exposure were sought on Medline and Toxnet RESULTS: Twenty-six experiments using thirteen different hydrocarbons were identified. Several human subtypes were observed including IgA nephritis, mesangial, proliferative and extracapillary glomerulonephritis, focal and focal-segmental sclerosis, minimal change nephropathy, anti-GBM and anti-TBM nephritis, and glomerulonephritis associated with peiarteritis nodosa. Glomerular proteinuria was seen in 10/12 experiments that included urine analyses, and renal failure in 5/8 experiments that included measurements of glomerular function. All experiments resulted in various degrees of tubular damage as well. In most studies, where the animals were examined at different times during or after the exposure, the renal microscopic and functional changes were seen immediately, whereas deposits of complement and immunoglobulins appeared late in the course, if at all. CONCLUSION: These experiments are in accord with epidemiological evidence that hydrocarbon exposure may cause glomerulonephritis and worsen renal function. Probable mechanisms include an induction of autologous antibodies and a disturbance of normal immunological functions. Also, tubular damage may increase postglomerular resistance, resulting in a glomerular deposition of macromolecules. In most models a causal role of glomerular immune complex formation was unlikely, but may rather have been a secondary phenomenon. As most glomerulonephritis subgroups were seen and as some of the hydrocarbons produced more than one subgroup, the microscopic findings in a patient cannot be used as a clue to the causation of his disease. By the same reason, the lack of a specific histological pattern in patients with glomerulonephritis assumed to have been caused by hydrocarbon exposure is not contradictive.


Assuntos
Glomerulonefrite/induzido quimicamente , Glomerulonefrite/patologia , Hidrocarbonetos , Animais , Glomerulonefrite/classificação , Glomerulonefrite/fisiopatologia , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência
19.
Expert Rev Clin Pharmacol ; 8(2): 201-10, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25672965

RESUMO

We have provided a critical assessment of research on the reduction of cholesterol levels by statin treatment to reduce cardiovascular disease. Our opinion is that although statins are effective at reducing cholesterol levels, they have failed to substantially improve cardiovascular outcomes. We have described the deceptive approach statin advocates have deployed to create the appearance that cholesterol reduction results in an impressive reduction in cardiovascular disease outcomes through their use of a statistical tool called relative risk reduction (RRR), a method which amplifies the trivial beneficial effects of statins. We have also described how the directors of the clinical trials have succeeded in minimizing the significance of the numerous adverse effects of statin treatment.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Ensaios Clínicos como Assunto/métodos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Animais , Ensaios Clínicos como Assunto/normas , Interpretação Estatística de Dados , Enganação , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Prevenção Primária/métodos , Projetos de Pesquisa/normas , Risco , Prevenção Secundária/métodos
20.
J Clin Epidemiol ; 55(11): 1057-63, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12507667

RESUMO

An almost endless number of observations and experiments have effectively falsified the hypothesis that dietary cholesterol and fats, and a high cholesterol level play a role in the causation of atherosclerosis and cardiovascular disease. The hypothesis is maintained because allegedly supportive, but insignificant findings, are inflated, and because most contradictory results are misinterpreted, misquoted or ignored.


Assuntos
Colesterol na Dieta/efeitos adversos , Doença das Coronárias/etiologia , Dieta Aterogênica , Colesterol/sangue , Doença das Coronárias/sangue , Gorduras na Dieta/efeitos adversos , Métodos Epidemiológicos , Ácidos Graxos Monoinsaturados/administração & dosagem , Humanos , Pesquisa , Fatores de Risco
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