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J J Kastelein

Publications and source records attributed to J J Kastelein.

At least 19 recordsLinked to original sources
PubMed2004

[Genetic screening of patients with familial hypercholesterolemia and insurability for life insurance policies and disability cover policies].

In the Netherlands, people with familial hypercholesterolaemia (FH) have been actively screened since 1994 by means of DNA analysis. Recently, the Stichting Opsporing Erfelijke Hypercholesterolemie (Foundation for the Detection of Familial Hypercholesterolaemia) initiated a large scale-screening programme aimed at finding all 40,000 people. The Dutch ministry of Health, Welfare and Sport is providing the financial support. Genetic screening has social implications and raises questions on insurability. The Dutch Medical Examination Act prohibits insurers from posing questions about untreatable, serious inheritable conditions for insured sums under a certain value: for life-insurance policies < [symbol: see text] 150,000 and for disability-cover policies < [symbol: see text] 30,000 in the 1st year and < [symbol: see text] 20,000 in the 2nd year and following years. The Health Council of the Netherlands has defined FH as a serious disease, but one which responds well to treatment. Therefore insurers can request information for the purpose of an accurate risk classification. Insurance contracts can be accepted at normal rates if the target value of LDL-cholesterol < 4 mmol/l and additional risk factors such as smoking and an abnormal BMI are absent; the risk is determined by the phenotype and clinical factors and not by the genotype.

DNA Mutational Analysis↗
PubMed2001

Nevirapine-containing antiretroviral therapy in HIV-1 infected patients results in an anti-atherogenic lipid profile.

BACKGROUND: Protease inhibitor-containing antiretroviral therapy for the treatment of HIV-1 infection is associated with elevated triglyceride and low-density lipoprotein (LDL)-cholesterol levels which may expose patients to an increased risk of coronary artery disease (CAD). We report the lipid and lipoprotein profiles of a representative subset of treatment-naive patients included in the Atlantic Study. This study compares patients treated with stavudine and didanosine plus the random addition of either the non-nucleoside reverse transcriptase inhibitor nevirapine (NVP), the protease inhibitor indinavir or the nucleoside reverse transcriptase inhibitor lamivudine. METHODS: Lipids and lipoproteins were quantified from prospectively collected and cryopreserved plasma samples obtained at weeks 0, 6 and 24. RESULTS: We observed a striking increase in high-density lipoprotein (HDL)-cholesterol (49%), apolipoprotein AI (19%), lipoprotein AI (38%) and HDL particle size (3%) in the NVP-treated patients (n = 34) at week 24. Much less pronounced changes in these parameters were seen to a similar extent both in patients receiving lamivudine (n = 39) and indinavir (n = 41). LDL-cholesterol also increased significantly both in the NVP and indinavir arms, but only in the NVP arm was this offset by a significant reduction (14%) in total over HDL-cholesterol ratio. Using a multivariate linear regression model, adjusting for CD4 cell count and plasma HIV RNA both at baseline and during treatment, randomization to the NVP-containing arm remained significant in explaining the observed changes in HDL-cholesterol and other HDL-related parameters. CONCLUSIONS: In HIV-1 infected patients treated with a regimen of stavudine, didanosine and NVP we found changes in lipids and lipoproteins which are associated with a sharp decrease in risk for CAD in other settings. If confirmed in larger studies, these findings both may influence the initial choice of therapy for HIV-1 infection, and might lead to novel approaches targeted at raising HDL-cholesterol for CAD prevention.

Adult↗
PubMed2001

Mortality over two centuries in large pedigree with familial hypercholesterolaemia: family tree mortality study.

OBJECTIVE: To estimate all cause mortality from untreated familial hypercholesterolaemia free from selection for coronary artery disease. DESIGN: Family tree mortality study. SETTING: Large pedigree in Netherlands traced back to a single pair of ancestors in the 19th century. SUBJECTS: All members of pedigree aged over 20 years with 0.5 probability of carrying a mutation for familial hypercholesterolaemia. MAIN OUTCOME MEASURE: All cause mortality. RESULTS: A total of 70 deaths took place among 250 people analysed for 6950 person years. Mortality was not increased in carriers of the mutation during the 19th and early 20th century; it rose after 1915, reached its maximum between 1935 and 1964 (standardised mortality ratio 1.78, 95% confidence interval 1.13 to 2.76; P=0.003), and fell thereafter. Mortality differed significantly between two branches of the pedigree (relative risk 3.26, 95% confidence interval 1.74 to 6.11; P=0.001). CONCLUSIONS: Risk of death varies significantly among patients with familial hypercholesterolaemia. This large variability over time and between branches of the pedigree points to a strong interaction with environmental factors. Future research is required to identify patients with familial hypercholesterolaemia who are at extreme risk and need early and vigorous preventive measures.

Adult↗
PubMed2001

Common genetic variation in ABCA1 is associated with altered lipoprotein levels and a modified risk for coronary artery disease.

BACKGROUND: Low plasma HDL cholesterol (HDL-C) is associated with an increased risk of coronary artery disease (CAD). We recently identified the ATP-binding cassette transporter 1 (ABCA1) as the major gene underlying the HDL deficiency associated with reduced cholesterol efflux. Mutations within the ABCA1 gene are associated with decreased HDL-C, increased triglycerides, and an increased risk of CAD. However, the extent to which common variation within this gene influences plasma lipid levels and CAD in the general population is unknown. METHODS AND RESULTS: We examined the phenotypic effects of single nucleotide polymorphisms in the coding region of ABCA1. The R219K variant has a carrier frequency of 46% in Europeans. Carriers have a reduced severity of CAD, decreased focal (minimum obstruction diameter 1.81+/-0.35 versus 1.73+/-0.35 mm in noncarriers, P:=0.001) and diffuse atherosclerosis (mean segment diameter 2.77+/-0.37 versus 2.70+/-0.37 mm, P:=0.005), and fewer coronary events (50% versus 59%, P:=0.02). Atherosclerosis progresses more slowly in carriers of R219K than in noncarriers. Carriers have decreased triglyceride levels (1.42+/-0.49 versus 1.84+/-0.77 mmol/L, P:=0.001) and a trend toward increased HDL-C (0.91+/-0.22 versus 0.88+/-0.20 mmol/L, P:=0.12). Other single nucleotide polymorphisms in the coding region had milder effects on plasma lipids and atherosclerosis. CONCLUSIONS: These data suggest that common variation in ABCA1 significantly influences plasma lipid levels and the severity of CAD.

ATP Binding Cassette Transporter 1↗
PubMed2001

Effect of aggressive versus conventional lipid lowering on atherosclerosis progression in familial hypercholesterolaemia (ASAP): a prospective, randomised, double-blind trial.

BACKGROUND: High LDL-cholesterol is a risk factor for atherosclerosis. We aimed to determine whether aggressive cholesterol lowering with statins was more effective than conventional statin treatment in this disease. We investigated the effect of high-dose atorvastatin on carotid atherosclerosis progression. METHOD: We did a randomised, double-blind clinical trial in 325 patients with familial hypercholesterolaemia. Patients were given either atorvastatin 80 mg (n=160) or simvastatin 40 mg (n=165) daily, on an intent-to-treat basis. The primary endpoint was the change of carotid intima media thickness (IMT), as measured by quantitative B-mode ultrasound, over 2 years. FINDINGS: The overall baseline IMT, combining the measurements of the common and internal carotid artery and the carotid bifurcation on both sides, was 0.93 mm (SD 0.22) and 0.92 mm (0.21) in the atorvastatin and simvastatin groups, respectively. After treatment with atorvastatin for 2 years, IMT decreased (-0.031 mm [95% CI -0.007 to -0.055]; p=0.0017), whereas in the simvastatin group it increased (0.036 [0.014-0.058]; p=0.0005). The change in thickness differed significantly between the two groups (p=0.0001). Atorvastatin showed greater reductions in cholesterol concentrations than did simvastatin. HDL-cholesterol concentrations increased in both groups. Both drugs were equally well tolerated. INTERPRETATION: Our results show that aggressive LDL-cholesterol reduction by atorvastatin was accompanied by regression of carotid intima media thickness in patients with familial hypercholesterolaemia, whereas conventional LDL lowering was not.

Adult↗
PubMed2001

PON2 gene variants are associated with clinical manifestations of cardiovascular disease in familial hypercholesterolemia patients.

Paraoxonase is an enzyme associated with the high-density lipoprotein (HDL) particle. It catalyses the hydrolysis of organophosphates and protects LDL from oxidative modification in vitro by hydrolyzing lipid peroxides, suggestive of a role for paraoxonase in the development of atherosclerosis. Two frequent mutations at the paraoxonase gene locus (PON1) underlie the leucine (Leu allele) --> methionine (Met allele) and the glutamine(Gln allele) --> arginine(Arg allele) aminoacid substitutions at residues 55 and 192, respectively. These polymorphisms have been associated with increased risk for cardiovascular disease (CVD) in several studies, while others have not found this association. Recently, another member of the PON gene family designated PON2 has been identified. While the PON2 gene product is expressed ubiquitously, its physiological role is unknown. A common polymorphism at codon 311 (Cys-->Ser) in the PON2 gene has been described. In our study we assessed the frequency and genotype distribution of the PON1 and PON2 polymorphisms in 197 patients with familial hypercholesterolemia (FH), to determine the possible association between these mutations and susceptibility for CVD. The FH cohort group was divided into subjects with (n=83) and without (n=114) definite clinical manifestations of CVD (FH-Symptomatic and FH-Asymptomatic respectively). The control population consisted of 201 healthy normolipidemic blood donors. All subjects in this study were of Caucasian background. Genotypes were identified by PCR based analysis. With regard to the PON1 polymorphisms 55 and 192, no different distributions of allele frequencies were found between the groups studied. However, we did show an association between the PON2 311 polymorphism and CVD. The frequencies of PON2 Ser311 carriers (Ser/Ser and Cys/Ser) between FH-Symptomatic and both FH-Asymptomatic and controls did show a significant difference (P=0.01 and P=0.02 respectively). In the FH-Symptomatic population, surprisingly, no subjects were homozygous for PON2 Cys311, whereas in the FH-Asymptomatic population nine persons (7.9%) and in the control group 12 persons (6.0%) were homozygous. Our data indicate that the common PON2 polymorphism is associated with clinical manifestations of CVD in FH patients. While PON2 Ser311 carriers seem to be at risk, subjects with the Cys/Cys311 genotype are likely to be protected against the development of premature CVD.

Adult↗
PubMed2001

Review of first 5 years of screening for familial hypercholesterolaemia in the Netherlands.

BACKGROUND: Familial hypercholesterolaemia is a common lipid disorder that predisposes for premature cardiovascular disease (CVD). We set up a screening programme in the Netherlands in 1994 to: establish the feasibility of active family screening supported by DNA diagnostics; assess whether or not active identification of these patients with familial hypercholesterolaemia would lead to more cholesterol-lowering treatment; and compare diagnosis by DNA analysis with that by cholesterol measurement. METHODS: Both DNA analysis and measurement of cholesterol concentrations were used to screen families in which a functional mutation in the LDL-receptor gene had been detected. FINDINGS: In the first 5 years, 5442 relatives of 237 people with familial hypercholesterolaemia were screened; 2039 individuals were identified as heterozygous by LDL-receptor gene mutation analysis. At the time of examination, 667 of these adults with familial hypercholesterolaemia (39%) received some form of lipid-lowering treatment; 1 year later, this percentage had increased to 93%. In addition, laboratory analysis showed that for carriers as well as non-carriers 18% would have been misdiagnosed by cholesterol measurement alone, with sex-specific and age-specific 90th percentiles of the general Dutch population as diagnostic criteria. INTERPRETATION: Targeted family screening with DNA analysis proved to be highly effective in identifying patients with hypercholesterolaemia. Most of the identified patients sought treatment and were successfully started on cholesterol-lowering treatment to lower the risk of premature CVD. Our findings could have wider relevance for the screening of other prevalent genetic disorders in the population at large.

Adult↗
PubMed2001

Parental history of myocardial infarction: lipid traits, gene polymorphisms and lifestyle.

To investigate the relationship between parental history of myocardial infarction (MI), lipid traits and gene polymorphisms involved in lipid metabolism, we examined Dutch men and women, who were selected from a large population-based study. Subjects whose father (n=112), mother (n=115) or both parents (n=115) suffered from a premature MI presented with significantly higher apolipoprotein B (apo B) levels than subjects without a parental history (n=114). Genetic analyses revealed that the apo E4 isoform and the D9N mutation of lipoprotein lipase (LPL) were more frequent among subjects with a parental history (P< or =0.05). A similar trend was found for the LPL N291S mutation. In contrast, the LPL S447X mutation and polymorphisms at the cholesteryl ester transfer protein (TaqIB) and apo CIII (SstI) loci proved to be noninformative. Body mass index and lifestyle could not explain differences in apo B levels between parental history groups. In contrast, the apo E polymorphism and the LPL D9N mutation accounted for some, but not all, of the higher apo B levels in subjects with a parental history. Therefore, other genetic or lifestyle-related factors must be responsible for the increased levels of apo B in individuals with a family history of myocardial infarction.

Adult↗
PubMed2001

A comparison of the efficacy and tolerability of titrate-to-goal regimens of simvastatin and fluvastatin: a randomized, double-blind study in adult patients at moderate to high risk for cardiovascular disease.

BACKGROUND: Use of cholesterol-lowering regimens has been shown to reduce the risk of coronary heart disease (CHD), both in primary and secondary prevention. However, there have been few studies of the relative benefits and risks of the various cholesterol-lowering agents in patient groups with specific risk factors for CHD. OBJECTIVE: The primary goal of this study was to compare the proportions of adult patients with primary hypercholesterolemia and a moderate to high risk for CHD achieving National Cholesterol Education Program low-density lipoprotein cholesterol (LDL-C) goals with titrate-to-goal regimens of simvastatin and fluvastatin. METHODS: This was a multicenter, prospective, randomized, double-blind, parallel-group study enrolling adult patients with type IIa or IIb primary hypercholesterolemia, LDL-C levels <6.0 mmol/L (<232.0 mg/dL), and triglyceride levels <4.5 mmol/L (<398.6 mg/dL), and either CHD or other atherosclerotic disease (the CHD, or high-risk, group), or multiple risk factors for CHD (the MRF, or moderate-risk, group). After a 6-week washout period, patients were randomized to 18 weeks of treatment at an initial dosage of simvastatin 10 mg once daily or fluvastatin 20 mg once daily. At 6- and 12-week titration visits, the dosage in patients who had not acheived the LDL-C goal could be increased to simvastatin 20 mg once daily and then 40 mg once daily, or to fluvastatin 40 mg once daily and then 40 mg twice daily. Lipid profiles were obtained at each titration visit and at the end of treatment. In addition to the comparison between treatments, secondary comparisons were made between the CHD and MRF subgroups within each treatment group. Statistical significance was assessed using analysis of variance. RESULTS: A total of 478 patients were enrolled, 237 in the simvastatin group and 241 in the fluvastatin group. There were no significant between-group differences in patients' characteristics at baseline. At the end of the study, 60.8% (135/222) of patients in the simvastatin group had reached target LDL-C goals, compared with 35.1% (76/216) in the fluvastatin group (P < 0.001). In the simvastatin CHD and MRF subgroups, 49% and 73%, respectively, reached the LDL-C target, compared with 19% and 50% in the corresponding fluvastatin subgroups (P < 0.001). The proportion of patients requiring titration was higher in the fluvastatin group than in the simvastatin group (87.1% and 64.1%, respectively; P = 0.001). The incidence of adverse events was similar between groups. CONCLUSION: In this study, more patients with primary hypercholesterolemia and CHD or multiple risk factors for CHD reached LDL-C goals with simvastatin treatment and required less titration than those who received fluvastatin treatment.

Adult↗
PubMed2001

Genetic and metabolic factors predicting risk of cardiovascular disease in familial hypercholesterolemia.

Familial hypercholesterolemia is a hereditary metabolic disorder characterised by high low-density lipoprotein cholesterol levels and an extreme risk of premature cardiovascular disease. In patients with heterozygous familial hypercholesterolemia a substantial variation is seen in both the severity of the hypercholesterolemia and onset of atherosclerotic disease symptoms. We discuss the contribution of additional atherogenic risk factors of metabolic, environmental and genetic origin. Subclinical disease measurements, such as the intima media thickness (IMT), assessed by ultrasonography, may contribute to a better risk prediction of future cardiovascular disease in these patients.

Apolipoproteins B↗
PubMed2001

The LPL S447X cSNP is associated with decreased blood pressure and plasma triglycerides, and reduced risk of coronary artery disease.

Linkage of the lipoprotein lipase (LPL) gene to blood pressure levels has been reported. The LPL S447X single nucleotide polymorphism (cSNP) has been associated with decreased triglycerides (TG), increased high density lipoprotein cholesterol, and a decreased risk of coronary artery disease (CAD), which may occur independently of its beneficial lipid changes. To investigate the relationship between LPL S447X cSNP and these parameters, we studied a cohort of individuals with familial hypercholesterolemia in whom blood pressures and information regarding the use of blood pressure lowering medications were available. Carriers of the S447X variant had decreased TG (1.21+/-0.47 vs. 1.52+/-0.67, p<0.001) and a trend towards decreased vascular disease (12.7 vs. 19.5%) compared to non-carriers. More interestingly, however, carriers of this cSNP had decreased diastolic blood pressure compared to non-carriers (78+/-10 vs. 82+/-11, p=0.002), evident in both men and women, youths and adults, with similar trends for systolic blood pressure. Furthermore, the decrease in blood pressure appeared independent of the decrease in TG (p=0.02), suggesting that the LPL protein may have a direct influence on the vascular wall. This suggests an additional mechanism whereby this variant may have protective effects, independent of changes in plasma lipid levels.

Adolescent↗
PubMed2001

Increased risk for ischaemic events is related to combined RAS polymorphism.

OBJECTIVE: To determine whether the angiotensin converting enzyme (ACE) and the angiotensin II type 1 receptor (AT(1)R A1166C) gene polymorphism interact to increase the risk of ischaemic events, and whether this can be explained by the progression of angiographically defined coronary atherosclerosis. DESIGN: Prospective defined substudy of the lipid lowering regression trial (REGRESS). SETTING: University hospital. PATIENTS: 885 male patients with stable coronary artery disease. MAIN OUTCOME MEASURES: Incidence of ischaemic events during a two year follow up; serial quantitative coronary arteriography (mean segment diameter and minimum obstruction diameter) at baseline and after two years. RESULTS: Patients who carried both the ACE-DD and AT(1)R-CC genotype had significantly more ischaemic events during the two year follow up than those carrying other genotype combinations (p = 0.035, Mantel-Haenszel test for linear association). There was no association between the two genotypes and mean segment diameter or minimum obstruction diameter at baseline or after two years. CONCLUSIONS: The suggestion that ACE-DD and AT(1)R-CC genotypes interact to increase the risk of ischaemic events is confirmed. However, this increased risk was not accompanied by increased progression of angiographically defined coronary atherosclerosis.

Coronary Angiography↗
PubMed2000

Lipoprotein lipase activity is associated with severity of angina pectoris. REGRESS Study Group.

BACKGROUND: Raised triglyceride-rich lipoproteins significantly increase the risk for cardiovascular disease. Variation in the activity of the enzyme lipoprotein lipase (LPL), which is crucial in the removal of these lipoproteins, may therefore modulate this risk. METHODS AND RESULTS: Postheparin levels of LPL activity and mass were measured in a large cohort of male coronary artery disease patients participating in the Regression Growth Evaluation Statin Study (REGRESS), a lipid-lowering regression trial. In addition, the relationships between LPL activity and mass and severity of angina pectoris according to the NYHA classification and silent ischemia on 24-hour ambulatory ECG monitoring were assessed. Patients in different LPL activity quartiles and mass had different severities of angina; a total of 47% of patients in the lowest LPL quartile reported class III or IV angina. In contrast, only 29% in the highest activity quartile (P:=0.002) had severe angina. These parameters were supported by ambulatory ECG results, for which the total ischemic burden in the lowest LPL activity quartile was 36. 5+/-104.1 mm x min compared with 14.8+/-38.8 mm x min in the highest quartile of LPL activity (P:=0.001). LPL activity levels were strongly correlated with LPL mass (r=0.70, P:<0.0001). A significant association between the LPL protein mass and NYHA class (P:=0.012) was also demonstrated. CONCLUSIONS: We have demonstrated a significant relationship between LPL mass and activity and severity of ischemia as defined by angina class and ambulatory ECG. These results suggest that LPL influences risk for coronary artery disease by both catalytic and noncatalytic mechanisms.

Aged↗
PubMed2000

[Familial hypercholesterolemia: recognition and prevention of cardiac complications at a young age].

A man aged 35 and a woman aged 30 visited a lipid clinic because of a raised total cholesterol level, which was also present in a number of first-degree relatives. Apart from the lipid abnormalities they had no risk factors for coronary disease. Both proved to have familial hypercholesterolaemia. The man had vague angina pectoris symptoms and a high dose of cholesterol synthesis inhibitors was prescribed. Coronary angiography showed severe stenoses; a coronary balloon angioplasty was successfully performed. The woman, however, died at age 33 suddenly from myocardial infarction. Familial hypercholesterolaemia may cause unexpected cardiovascular complications and sudden death of young persons. Timely diagnosis of the condition on the basis of adequate anamnesis and thorough physical examination, more rapid administration of cholesterol-lowering agents and alertness for anginous complaints may prevent myocardial infarctions and save lives in these patients.

Adult↗
PubMed2000

[Higher prevalence of familial hypercholesterolemia than expected in adult patients of four family practices in Netherlands].

OBJECTIVE: To determine the prevalence of familial hypercholesterolaemia (FH). DESIGN: Patient record screening, questionnaire and if necessary, case finding. METHODS: Over the period mid-1990-mid-1992 (approximately 2.5 years) 8,800 adult individuals (age 18 years and over) in 4 general practices in Hoofddorp, the Netherlands, were screened for risk factors for coronary artery disease and invited for further analysis. Of the 3,289 selected and invited individuals 2,719 (83%) were investigated. Total cholesterol concentrations were investigated 3 times and if the mean value was above 8.0 mmol/l patients were referred to a lipid clinic to investigate the possible existence of FH. RESULTS: 114 patients were eligible for referral to a lipid clinic of whom 92 (81%) were indeed referred. Of these, 38 patients were diagnosed with FH: 23 men and 15 women, with a mean age of 47.7 years (range: 21-74). CONCLUSION: The prevalence of FH in this investigated population was at least 1:232. This is more than 1:500, the estimated number of FH patients in the Dutch population.

Adult↗