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O Faergeman

Publications and source records attributed to O Faergeman.

At least 37 records · Page 2Linked to original sources
PubMed2000

Association of coronary heart disease with age-adjusted aortocoronary calcification in patients with familial hypercholesterolaemia.

OBJECTIVES: Existing algorithms of risk of coronary heart disease (CHD) do not pertain to patients with familial hypercholesterolaemia (FH), whose arteries have been exposed to hypercholesterolaemia since birth. We studied a cohort of FH patients to compare four diagnostic models of CHD: traditional risk factors of CHD (age, sex, cholesterol, hypertension, smoking and body mass index), cholesterol year score, and aortic as well as coronary calcium measured by spiral computed tomography (CT). SUBJECTS: We invited 88 individuals with molecularly defined FH of whom 80 (91%) decided to participate. RESULTS: Analysis of receiver operating characteristic curves showed that the age-adjusted coronary calcium score was more strongly associated with clinical manifestations of CHD than were traditional risk factors (P < 0.002), cholesterol year score (P << 0.0001), and the age-adjusted aortic calcium score (P < 0.0004). CONCLUSIONS: Age-adjusted coronary calcium score shows promise as an indicator of CHD in FH patients.

Adult↗
PubMed2000

Hypertriglyceridemia and the fibrate trials.

Epidemiological studies published since 1996 have established that hypertriglyceridemia can predict risk of cardiovascular disease in a manner statistically independent of HDL cholesterol. Nevertheless, the relationship of concentrations of plasma triglycerides to risk of cardiovascular disease remains less than straightforward, partly because triglycerides are carried in lipoproteins of different atherogenicity, partly because hypertriglyceridemia is associated with non-lipid atherogenic and thrombogenic processes. For example, the association of highest risk of cardiovascular disease to moderate rather than to severe hypertriglyceridemia can be understood in terms of the distribution of triglycerides between different classes of plasma lipoproteins. It is counter-intuitive to most clinicians, however, and hence it can result in the misdirection of clinical efforts including drug therapy. Fibrates lower plasma triglycerides, and raise HDL, efficiently and with few immediate side-effects. Central to their mode of action is activation of certain nuclear receptors in cells. There is no necessary connection, however, between that fascinating biochemistry and clinical benefit as defined by reductions in rates of death by coronary artery disease. A review of trials of cholesterol-lowering by diet and drugs, published between 1966 and 1996, included 12 trials of therapy with fibrates or placebo in more than 21000 patients. Overall, these trials indicated no benefit in terms of reduction in risk of coronary deaths. The period since 1996 has seen the publication of four additional trials of treatment of 6144 patients with fibrates or placebo. Two of them were major trials. The VA-HIT was very encouraging, because treatment with gemfibrozil produced a signficant reduction in the combined incidence of fatal and non-fatal coronary events. There was no significant reduction in coronary deaths, however. The results of BIP were frankly disappointing, because they demonstrated no significant effect of treatment with bezafibrate on either the primary end-point of the trial or on rates of coronary death. Clinical indications for the use of fibrates can obviously not be based on biochemical insights, however intriguing in their own right, but they have also not been satisfactorily defined by the randomized clinical trials published to date. Hope remains, however, that some clarification will result from ongoing trials of fibrate treatment of patients with type II diabetes.

Bezafibrate↗
PubMed2000

Flow cytometric assessment of effects of fluvastatin on low-density lipoprotein receptor activity in stimulated T-lymphocytes from patients with heterozygous familial hypercholesterolemia.

To test the effects of fluvastatin on low-density lipoprotein (LDL) receptor activity in patients with heterozygous familial hypercholesterolemia, the authors measured LDL receptor activity in stimulated T-lymphocytes prepared from 34 patients before and after treatment with 40 mg fluvastatin daily for 12 weeks. Maximally induced pretreatment LDL receptor activities did not correlate with pretreatment plasma cholesterol levels or with changes in plasma cholesterol levels during treatment, and there were no significant changes in LDL receptor activity during treatment. Barring methodological problems, two explanations are possible. Insofar that LDL receptor activity in lymphocytes reflects LDL receptor activity in the liver, the results suggest that the primary response to treatment with fluvastatin in heterozygous familial hypercholesterolemia (FH) patients is not enhanced LDL receptor activity. Alternatively, fluvastatin increases LDL receptor activity in hepatocytes but has little effect on receptor-dependent lipoprotein catabolism in extrahepatic tissues in vivo.

Amino Acid Substitution↗
PubMed2000

Flow cytometric assessment of LDL ligand function for detection of heterozygous familial defective apolipoprotein B-100.

BACKGROUND: Familial defective apolipoprotein (apo) B-100 (FDB) is caused by a mutation in the apoB gene and characterized by decreased binding of LDL to LDL receptors because of reduced function of the apoB-100 ligand. FDB may be associated with severe hypercholesterolemia and cannot always be distinguished from familial hypercholesterolemia phenotypically. METHODS: We used a fluorescence flow cytometry assay with Epstein-Barr virus-transformed lymphocytes to detect reduced LDL ligand function by competitive binding with fluorescently conjugated LDL (DiI-LDL). The assay was tested and validated using LDL from patients heterozygous for the Arg(3500)-Gln mutation and their first-degree relatives. Knowing the actual apoB genotype of patients and relatives allowed us to assess the ability of the assay to predict the results of DNA analysis. The results were compared to measurements of LDL ligand function in unrelated healthy control subjects to characterize functionally the Arg(3500)-Gln mutation. RESULTS: Fluorescence was significantly increased in cells incubated with DiI-LDL in competition with unlabeled LDL from FDB(R3500Q) heterozygotes compared with cells incubated with DiI-LDL in competition with unlabeled LDL from relatives or unrelated healthy control subjects. Thus, patients heterozygous for the Arg(3500)-Gln mutation had significantly reduced LDL ligand function. The binding affinity of LDL from FDB(R3500Q) heterozygotes was 32% of that in non-FDB relatives and healthy controls. The assay had a diagnostic sensitivity of 0.95 and diagnostic specificity of 0.89. CONCLUSIONS: The diagnostic accuracy of the assay was too low to allow reliable diagnosis of individual cases of heterozygous FDB(R3500Q). However, fluorescence flow cytometry may supplement genetic identification of FDB and functionally characterize gene mutations associated with major reductions in LDL ligand function.

Adult↗
PubMed1999

Flow cytometric assessment of LDL receptor activity in peripheral blood mononuclear cells compared to gene mutation detection in diagnosis of heterozygous familial hypercholesterolemia.

BACKGROUND: Studies indicate that human peripheral blood mononuclear cells mirror low-density lipoprotein (LDL) receptor activity of other cells in the body. To measure LDL receptor activity in patients with heterozygous familial hypercholesterolemia (FH), we prepared peripheral blood mononuclear cells from individuals with molecularly verified LDL receptor defective (Trp66-Gly mutation, n = 18) or receptor negative (Trp23-stop mutation, n = 17) heterozygous FH and from healthy individuals (n = 24). METHODS: The cells were stimulated to express maximum LDL receptor by preincubation in lipoprotein-free medium. They were then incubated at 4 degrees or 37 degrees C with fluorescently conjugated LDL (DiI-LDL). T-lymphocytes and monocytes were identified by fluorescently conjugated monoclonal antibodies. DiI-LDL bound (at 4 degrees C) or internalized (at 37 degrees C) by the cells was measured using flow cytometry. Knowing the LDL receptor gene mutation of the FH patients allowed us to compare the diagnostic capability of our functional assay with the DNA diagnosis. RESULTS: The diagnostic accuracy did not allow our assay to be used for diagnosis of individual cases of heterozygous FH. CONCLUSIONS: We suggest that our two-color fluorescence flow cytometry assay can be used to characterize functionally gene mutations causing LDL receptor dysfunction in patients with heterozygous FH.

Arteriosclerosis↗
PubMed1999

P1A1/A2 polymorphism of platelet glycoprotein IIIa and risk of acute coronary syndromes in heterozygous familial hypercholesterolemia.

Familial hypercholesterolemia (FH) is an autosomal inherited disorder caused by different mutations in the low density lipoprotein (LDL) receptor gene. It has been demonstrated that there is an increased risk of coronary heart disease (CHD) in heterozygous FH subjects, although this excess CHD is not only explained by the LDL-cholesterol concentration or the class of the LDL-receptor mutation. To investigate if a common polymorphism at the platelet glycoprotein (GP) IIIa gene locus could be related to CHD phenotypic variation in heterozygous FH. we have carried out a case-control study. We have studied 40 cases and 40 controls matched for age, sex and genetic defect in the LDL-receptor gene. Allele frequency of PI(A2) polymorphism for cases and controls was 20 and 22.5%, respectively, and the difference was not significant. In conclusion, our data do not support any association between the GP IIIa polymorphism and the increased prevalence of acute coronary syndromes in the heterozygous FH subjects.

Acute Disease↗
PubMed1999

Spectrum of LDL receptor gene mutations in Denmark: implications for molecular diagnostic strategy in heterozygous familial hypercholesterolemia.

Heterozygous familial hypercholesterolemia (FH) is one of the most common potentially fatal single-gene diseases leading to premature coronary artery disease, but the majority of heterozygous FH patients have not been diagnosed. FH is due to mutations in the gene coding for the low-density lipoprotein (LDL) receptor, and molecular genetic diagnosis may facilitate identification of more FH subjects. The Danish spectrum of 29 different mutations, five of which account for almost half of heterozygous FH, is intermediate between that of countries such as South Africa, where three mutations cause 95% of heterozygous FH in the Afrikaners, and Germany or England, where there are many more mutations. In clinical practice, a strategy for the genetic diagnosis of heterozygous FH, tailored to the mutational spectrum of patients likely to be seen at the particular hospital/region of the country, will be more efficient than screening of the whole LDL receptor gene by techniques such as single-strand conformation polymorphism (SSCP) analysis in every heterozygous FH candidate. In Aarhus, Denmark, we have chosen to examine all heterozygous FH candidates for the five most common LDL receptor gene mutations (W23X, W66G, W556S, 313 + 1G --> A, 1846 - 1G --> A) and the apoB-3500 mutation by rapid restriction fragment analysis. Negative samples are examined for other mutations by SSCP analysis followed by DNA sequencing of the exon indicated by SSCP to contain a mutation. If no point mutation or small insertion/deletion is detected, Southern blot or Long PCR analysis is performed to look for the presence of large gene rearrangements. In conclusion, our data suggest that an efficient molecular diagnostic strategy depends on the composition of common and rare mutations in a population.

Adolescent↗
PubMed1999

Linking genotype to aorto-coronary atherosclerosis: a model using familial hypercholesterolemia and aorto-coronary calcification.

Most studies of the pathogenesis of coronary heart disease occur between gene variants and biochemical or physiological variables known to be atherogenic. In many situations, however, the gene products are not necessarily known. We studied 17 families (n = 122) with mutations in the low density lipoprotein (LDL) receptor gene as a model in which to test formally for linkage directly between an atherogenic genotype and ischemic heart disease (IHD) or aorto-coronary calcified atherosclerosis. In each family one of three different mutations was found: the Trp66-Gly mutation, the Trp23-Stop mutation, or a ten kilobase deletion removing exons 3-6 of the LDL receptor gene. Genomic DNA was used to determine these mutations by either enzymatic cleavage assays or Southern blotting. Aorto-coronary calcification was significantly associated with age and plasma cholesterol. Sex, hypertension, BMI and smoking were not associated with aorto-coronary calcification. Nonparametric analysis indicated significant linkage of the LDL receptor gene locus to aortic (p < 0.00005) and to aorto-coronary calcified atherosclerosis (p < 0.00001). Assuming a dominant mode of inheritance, significant linkage was detected for aortic (LOD = 3.89) and aorto-coronary calcified atherosclerosis (LOD = 4.10). We suggest that the atherogenicity of variations in other genes could be assessed by a similar approach.

Adult↗
PubMed1999

Normolipidemia and hypercholesterolemia in persons heterozygous for the same 1592 + 5G --> A splice site mutation in the low-density lipoprotein receptor gene.

In the present study, we have characterized a unique splice donor G to A substitution in the moderately conserved + 5 position in intron 10 of the low-density lipoprotein (LDL) receptor gene. In two Danish families, carriers of the 1592 + 5G --> A mutation display a clinical phenotype ranging from healthy normocholesterolemic persons to classical heterozygous familial hypercholesterolemia (FH) patients. Reverse transcription-polymerase chain reaction (RT-PCR) of RNA from Epstein Barr virus (EBV)-transformed lymphoblasts obtained from members of both families demonstrated abnormal splicing generating two aberrant mRNAs due to either alternative splicing and skipping of exon 10 or activation of a cryptic splice site in intron 10 inserting 66 intronic base pairs. These abnormally spliced mRNAs were predicted to encode two abnormal receptor proteins containing an in-frame deletion of 75 amino acids and an insertion of 22 novel amino acids, respectively. Results obtained by immunofluorescence staining, flow cytometry, and confocal microscopy of transfected Chang and COS-7 cells expressing normal and mutant LDL receptors were compatible with nearly complete retention of the mutant proteins in the endoplasmic reticulum. Quantitative measurements of LDL receptor mRNAs from EBV-transformed lymphoblasts, however, did not reveal any significant differences in variant mRNA contents between mutation carriers in the families that could be related to degree of hypercholesterolemia.

Adult↗
PubMed1998

[Attitude of patients toward detection of hereditary disease. Heterozygote familial hypercholesterolemia].

Molecular biology has enabled us to identify apparently healthy persons at high risk of genetic disease. The purpose of the present study was to examine attitudes to detection of disease and the present well-being in persons at risk of disease with a modifiable outcome-heterozygous Familial Hypercholesterolaemia (heFH). A questionnaire collecting information on impact on well-being and on attitudes to screening family members for heFH was mailed to heFH index patients and hypercholesterolaemic relatives. Anxiety was expressed by 44%, fear of ischaemic heart disease by 37% and diminished well-being by 13% of respondents. Six percent regretted that they were aware of their diagnosis, and 84% were in favour of screening their family. We conclude that a substantial proportion of persons with heFH experience anxiety due to heFH. A small minority regret being informed of the diagnosis of heFH, however, and a majority are in favour of family screening.

Adult↗
PubMed1998

Lipoprotein changes and reduction in the incidence of major coronary heart disease events in the Scandinavian Simvastatin Survival Study (4S)

BACKGROUND: The Scandinavian Simvastatin Survival Study (4S) randomized 4444 patients with coronary heart disease (CHD) and serum cholesterol 5.5 to 8.0 mmol/L (213 to 310 mg/dL) with triglycerides < or =2.5 mmol/L (220 mg/dL) to simvastatin 20 to 40 mg or placebo once daily. Over the median follow-up period of 5.4 years, one or more major coronary events (MCEs) occurred in 622 (28%) of the 2223 patients in the placebo group and 431 (19%) of the 2221 patients in the simvastatin group (34% risk reduction, P<.00001). Simvastatin produced substantial changes in several lipoprotein components, which we have attempted to relate to the beneficial effects observed. METHODS AND RESULTS: The Cox proportional hazards model was used to assess the relationship between lipid values (baseline, year 1, and percent change from baseline at year 1) and MCEs. The reduction in MCEs within the simvastatin group was highly correlated with on-treatment levels and changes from baseline in total and LDL cholesterol, apolipoprotein B, and less so with HDL cholesterol, but there was no clear relationship with triglycerides. We estimate that each additional 1% reduction in LDL cholesterol reduces MCE risk by 1.7% (95% CI, 1.0% to 2.4%; P<.00001). CONCLUSIONS: These analyses suggest that the beneficial effect of simvastatin in individual patients in 4S was determined mainly by the magnitude of the change in LDL cholesterol, and they are consistent with current guidelines that emphasize aggressive reduction of this lipid in CHD patients.

Adult↗
PubMed1998

Differences in the treatment of coronary heart disease between countries as revealed in the Scandinavian Simvastatin Survival Study (4S)

AIM: To assess differences in treatment of ischaemic heart disease in the Scandinavian countries. METHODS AND RESULTS: The Scandinavian Simvastatin Survival Study (4S) lasted 5.4 years and showed that death rates in 4444 patients with coronary heart disease were 30% lower in those treated with simvastatin to lower serum cholesterol than in those given placebo. Apart from this main result, the 4S provided detailed information on rates of death and other manifestations of coronary heart disease, as well as on use of non-lipid forms of therapy. There were substantial differences in 4S placebo group rates of mortality, coronary deaths and major coronary events between countries. Surgical and medical therapy varied importantly between countries. CONCLUSIONS: Major inter-country differences in rates of death and myocardial infarction in patients with coronary heart disease were likely to be due to a composite of differences in baseline characteristics including smoking. They occurred in a setting of very uneven exploitation of the potential for improving survival of patients with ischaemic heart disease.

Angiotensin-Converting Enzyme Inhibitors↗