Cornelis Kluft

Effect of moderate dose of alcohol with evening meal on fibrinolytic factors

Abstract Objectives: To evaluate the effects of moderate consumption of alcoholic beverages on the fibrinolytic system and to assess whether these effects could help explain the relation between moderate alcohol consumption and reduced coronary heart disease. Design: Four treatments were allocated in a randomised controlled order on four days over a period of 11 days. Setting: Metabolic ward of research institute. Subjects: Eight white healthy middle aged men. Interventions: Subjects were provided with food for the 11 days. On the four study days mineral water or 40 g of alcohol in the form of beer, wine, or spirits was consumed at dinner early in the evening. Main outcome measures: Plasminogen activator inhibitor activity, tissue type plasminogen activator antigen, and tissue type plasminogen activator activity one hour before and one, three, five, nine, and 13 hours after dinner with mineral water or alcoholic beverages. Results: After dinner with alcohol plasminogen activator inhibitor activity rose from 53 (SD 19)% to a maximum of 667 (283%) five hours after dinner (P<0.001). Tissue type plasminogen activator antigen levels rose from 5.3 (2.2) μg/l to a maximum of 10.8 (3.8) μg/l nine hours after dinner with alcohol (P<0.001). Plasminogen activator activity was reduced in the postprandial period (from 1387 (483) IU/l to 323 (288) IU/l five hours after eating; P<0.001) but was higher than normal early the next morning (1516 (809) IU/l after alcohol, 779 (516) IU/l after water; P=0.04). Conclusion: Moderate alcohol consumption with dinner affects plasminogen activator inhibitor activity, plasminogen activator antigen level, and tissue type plasminogen activator activity temporarily. The effects observed in the early morning are consistent with a decrease in risk of coronary heart disease in moderate drinkers.

Short-term oestrogen replacement therapy improves insulin resistance, lipids and fibrinolysis in postmenopausal women with NIDDM

Summary Oestrogen replacement therapy is associated with a decreased risk of cardiovascular disease in postmenopausal women. Patients with non-insulin-dependent diabetes mellitus (NIDDM) have an increased cardiovascular risk. However, oestrogen replacement therapy is only reluctantly prescribed for patients with NIDDM. In a double blind randomized placebo controlled trial we assessed the effect of oral 17 β -estradiol during 6 weeks in 40 postmenopausal women with NIDDM. Glycated haemoglobin (HbA1c), insulin sensitivity, suppressibility of hepatic glucose production, lipoprotein profile and parameters of fibrinolysis were determined. The oestrogen treated group demonstrated a significant decrease of HbA1c and in the normotriglyceridaemic group a significantly increased suppression of hepatic glucose production by insulin. Whole body glucose uptake and concentrations of non-esterified fatty acids did not change. LDL-cholesterol- and apolipoprotein B levels decreased, and HDL-cholesterol, its subfraction HDL2-cholesterol and apolipotrotein A1 increased. The plasma triglyceride level remained similar in both groups. Both the concentration of plasminogen activator inhibitor-1 antigen and its active subfraction decreased. Tissue type plasminogen activator activity increased significantly only in the normotriglyceridaemic group. Oestrogen replacement therapy improves insulin sensitivity in liver, glycaemic control, lipoprotein profile and fibrinolysis in postmenopausal women with NIDDM. For a definite answer as to whether oestrogens can be more liberally used in NIDDM patients, long term studies including the effect of progestogens are necessary. [Diabetologia (1997) 40: 843–849]

Both Raloxifene and Estrogen Reduce Major Cardiovascular Risk Factors in Healthy Postmenopausal Women: A 2-Year, Placebo-Controlled Study

Currently raloxifene, a selective estrogen receptor modulator, is being investigated as a potential alternative for postmenopausal hormone replacement to prevent osteoporosis and cardiovascular disease. We compared the 2-year effects of raloxifene on a wide range of cardiovascular risk factors with those of placebo and conjugated equine estrogens (CEEs). Analyses were based on 56 hysterectomized but otherwise healthy postmenopausal women aged 54. 8+/-3.5 (mean+/-SD) years who entered this double-blind study and who were randomly assigned to raloxifene hydrochloride 60 mg/d (n=15) or 150 mg/d (n=13), placebo (n=13), or CEEs 0.625 mg/d (n=15). At baseline and after 6, 12, and 24 months of treatment, we assessed serum lipids, blood pressure, glucose metabolism, C-reactive protein, and various hemostatic parameters. Compared with placebo, both raloxifene and CEEs lowered the level of low density lipoprotein cholesterol by 0.53 to 0.79 mmol/L (all P<0.04) and lowered, at 24 months, the level of fibrinogen by 0.71 to 0.86 g/L (all P<0.05). The effects of raloxifene and CEEs did not differ significantly. In contrast to raloxifene, from 6 months on CEEs increased high density lipoprotein cholesterol by 0.25 to 0.29 mmol/L and reduced plasminogen activator inhibitor-1 antigen by 30.6 to 48.6 ng/mL (all P<0.02 versus both placebo and raloxifene). CEEs transiently increased C-reactive protein by 1.0 mg/L at 6 months (P<0.05 versus placebo) and prothrombin-derived fragment F1+2 by 0. 79 nmol/L at 12 months (P<0.001 versus placebo). Finally, from 12 months on, CEEs increased triglycerides by 0.33 to 0.56 mmol/L (all P<0.05 versus both placebo and raloxifene). Our findings suggest that in healthy postmenopausal women, raloxifene and estrogen monotherapy have similar beneficial effects on low density lipoprotein cholesterol and fibrinogen levels. These treatments differ, however, in their effects on high density lipoprotein cholesterol, triglycerides, and plasminogen activator inhibitor-1 and possibly in their effects on prothrombin fragment F1+2 and C-reactive protein.

Association of depressive disorders, depression characteristics and antidepressant medication with inflammation.

Growing evidence suggests that immune dysregulation may be involved in depressive disorders, but the exact nature of this association is still unknown and may be restricted to specific subgroups. This study examines the association between depressive disorders, depression characteristics and antidepressant medication with inflammation in a large cohort of controls and depressed persons, taking possible sex differences and important confounding factors into account. Persons (18–65 years) with a current (N=1132) or remitted (N=789) depressive disorder according to DSM-IV criteria and healthy controls (N=494) were selected from the Netherlands Study of Depression and Anxiety. Assessments included clinical characteristics (severity, duration and age of onset), use of antidepressant medication and inflammatory markers (C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α)). After adjustment for sociodemographics, currently depressed men, but not women, had higher levels of CRP (1.33 versus 0.92 mg l−1, P<0.001, Cohens d=0.32) and IL-6 (0.88 versus 0.72 pg ml−1, P=0.01, Cohens d=0.23) than non-depressed peers. Associations reduced after considering lifestyle and disease indicators — especially body mass index — but remained significant for CRP. After full adjustment, highest inflammation levels were found in depressed men with an older age of depression onset (CRP, TNF-α). Furthermore, inflammation was increased in men using serotonin–norepinephrine reuptake inhibitors (CRP, IL-6) and in men and women using tri- or tetracyclic antidepressants (CRP), but decreased among men using selective serotonin reuptake inhibitors (IL-6). In conclusion, elevated inflammation was confirmed in depressed men, especially those with a late-onset depression. Specific antidepressants may differ in their effects on inflammation.

Genome-wide association of major depression: description of samples for the GAIN Major Depressive Disorder Study: NTR and NESDA biobank projects

To identify the genomic regions that confer risk and protection for major depressive disorder (MDD) in humans, large-scale studies are needed. Such studies should collect multiple phenotypes, DNA, and ideally, biological material that allows gene expression analysis, transcriptomic, proteomic, and metabolomic studies. In this paper, we briefly review linkage studies of MDD and then describe the large-scale nationwide biological sample collection in Dutch twin families from the Netherlands Twin Register (NTR) and in participants in the Netherlands Study of Depression and Anxiety (NESDA). Within these studies, 1862 participants with a diagnosis of MDD and 1857 controls at low liability for MDD have been selected for genome-wide genotyping by the US Foundation for the National Institutes of Health Genetic Association Information Network. Stage 1 genome-wide association results are scheduled to be accessible before the end of 2007. Genome-wide association results are open-access and can be viewed at the dbGAP web portal (http://www.ncbi.nlm.nih.gov). Approved users can download the genotype and phenotype data, which have been made available as of 9 October 2007.

Reduced response to activated protein C is associated with increased risk for cerebrovascular disease

Resistance to activated protein C (APC) is a recently described coagulation abnormality [1] that is associated with increased risk for venous thromboembolism [2, 3]. The balance of procoagulant and anticoagulant factors undoubtedly plays a critical role in determining the risk for coronary [4, 5] and cerebral thromboembolism [6, 7]. Therefore, some studies [8, 9] have suggested that resistance to APC may also be associated with increased risk for arterial disease. Other studies [10-13], however, have not found evidence to support this conclusion. An extremely low response to APC is often caused by the single-base, Arg 506 to Gln mutation of the factor V gene [14, 15]. This mutation affects the site of cleavage of activated factor V by APC, rendering it relatively resistant to inactivation; the resistance, in turn, leads to increased thrombotic tendency. Accordingly, a functional test for response to APC is used to screen for the factor V mutation. Patients with values below an arbitrarily chosen point are considered potential carriers of the mutation. However, a low response to APC can be caused by other factors; not all patients with low values are carriers of the factor V mutation [16]. We studied whether response to APC is associated with arterial disease by comparing levels of response to APC and prevalence of the factor V Leiden mutation in patients with and without a history of stroke, transient ischemic attack, or myocardial infarction. We also examined other determinants of the level of response to APC. Methods Population We did a casecontrol study of participants in the Rotterdam Study, which is a prospective study of 7983 men and women 55 years of age and older. The rationale and design of the Rotterdam Study have been described elsewhere [17]. Between March 1990 and July 1993, all men and women 55 years of age and older living in Ommoord, a district of Rotterdam, the Netherlands, were invited to participate (n = 10 275). The overall response rate was 78%. The study was approved by the ethics committee of Erasmus University, and written informed consent was obtained from all participants. Selection Patients with a history of myocardial infarction (n = 115) were selected if they had an infarction shown by electrocardiography. Selection was made using the diagnostic classification system of the Modular Electrocardiogram Analysis System (MEANS) [18, 19], independent of a history of chest pain. Patients with a definite or probable history of transient ischemic attack (n = 55) were selected if they had a positive medical history of transient ischemic attack. Four screening questions were asked about temporary visual, locomotor, sensory, or speech disturbances; when responses were affirmative, a detailed history of symptoms was obtained. Symptoms were classified by a neurologist as indicating that the patient had definitely, had probably, or had not had a transient ischemic attack, using methods described elsewhere [20]. Patients with a history of stroke (n = 62) were selected by the question, Did you ever suffer from stroke, diagnosed by a physician? Five patients had a history of both transient ischemic attack and stroke. Therefore, 112 patients were classified as having cerebrovascular disease, which was defined as a stroke, a transient ischemic attack, or both. Controls (n = 222) were selected from among those persons with a normal electrocardiogram, an ankle-to-arm systolic pressure ratio greater than 0.9 (the ankle-to-arm systolic pressure ratio is the ratio of the systolic blood pressure at the posterior tibial artery to the systolic blood pressure at the arm), and no arterial disease (that is, no history of myocardial infarction, stroke, or transient ischemic attack) [21]. Controls were matched in 5-year age strata to persons who had had myocardial infarction. Patients using anticoagulant drugs were excluded. Measurements Information on current health status, medical history, drug use, and smoking was obtained by using a questionnaire. We measured height and weight and calculated body mass index. We measured blood pressure at the right upper arm while patients were seated by using a random-zero sphygmomanometer, and we used the average of two measurements obtained on one occasion. The electrocardiogram was coded using the MEANS computerized coding system [18, 19]. The methods we used for blood sampling and storage have been described elsewhere [22]. Blood was collected in tubes containing 0.129 mol/L sodium citrate. Platelet-poor plasma was obtained by two-stage centrifugation: Samples were centrifuged at 1600 g and 4 C for 10 minutes; after the plasma midlayer was carefully transferred, a second centrifugation was done at 10 000 g and 4 C for 10 minutes. Plasma was immediately frozen in liquid nitrogen and stored at 80C for a mean of 2 years. Plasma from 30 healthy volunteers was centrifuged for 30 minutes at 2000 g and 4 C and was pooled to serve as reference plasma for the test of response to APC. The response to APC for the reference plasma was 3.27. The response of the plasma-activated partial thromboplastin time to APC was determined using the Coatest APC resistance test of Chromogenix (kit 0548-51, Molndal, Sweden) and is expressed as the ratio of the activated partial thromboplastin time with the addition of APC to the activated partial thromboplastin time without the addition of APC. Serum total and high-density lipoprotein (HDL) cholesterol levels were measured with an automated enzymatic procedure. Whole blood that was collected and stored at baseline was thawed for DNA extraction. Genotype assay using polymerase chain reaction was done by laboratory personnel who were blinded to case or control status. The Arg 506 to Gln mutation was detected by amplification of a 220-base pair fragment of exon 10-intron 10 of the factor V gene, followed by digestion with the restriction enzyme Mnl I. The primers and conditions that we used have been described elsewhere [14, 23]. Statistical Analysis We calculated means and proportions for potential determinants for five categories of response to APC and adjusted for a history of myocardial infarction or cerebrovascular disease (two dummy variables in the regression model) using linear regression analysis. Logistic regression was used to assess the association of response to APC and the factor V Leiden mutation with cerebrovascular disease and myocardial infarction. Odds ratios with corresponding 95% CIs estimated from the logistic model were used as the measure of association. With myocardial infarction or cerebrovascular disease as the outcome variable, we compared levels of response to APC and genotypes of the factor V mutation adjusted for age and sex. By adding current smoking, total cholesterol level, and activated partial thromboplastin time as covariates in the logistic regression model, we evaluated whether these potentially confounding factors affected the estimates of the odds ratios. In addition, logistic regression was used to explore the association of disease status with response to APC as a continuous variable. Information on factor V mutation was missing for five participants for whom no blood cells were available. In the regression models with factor V as a confounder, the indicator method for missing data was used [24]. The results were similar to analyses done without these participants. Results Response to Activated Protein C The response to APC ranged from 1.5 to 9.5. Mean responses (SD) were 4.3 1.1 among controls, 3.9 1.0 among patients with a history of cerebrovascular disease, and 4.3 1.1 among patients with a history of myocardial infarction. Mean response to APC was 2.5 0.6 in participants with the factor V mutation and 4.3 1.0 in those without the mutation. The response to APC was higher in men (n = 202; response, 4.5 [CI, 4.4 to 4.7]) than in women (n = 247; response, 3.9 [CI, 3.8 to 4.1]). Several cardiovascular risk factors were compared across five levels of response for men and women (Table 1). In men, response to APC decreased with increasing age by 0.18 (CI, 0.01 to 0.35) per decade. In women, a trend of 0.08 (CI, 0.06 to 0.23) per decade was seen toward an increase in response to APC with advancing age. Men who smoked had a mean response that was 0.47 (CI, 0.16 to 0.78) higher than that of men who did not smoke. Response to APC of women who smoked did not differ from that of women who did not. Increased cholesterol levels were associated with a decreased response to APC in men but not in women. In men, an increase in cholesterol level of 1 mmol/L was associated with a decrease in response to APC of 0.14 (CI, 0.01 to 0.27). Table 1. Cardiovascular Risk Factors in Response to Activated Protein C* The odds ratio of cerebrovascular disease (stroke and transient ischemic attack) increased gradually with decreasing response to APC (odds ratio per 1-unit decrease, 1.43 [CI, 1.12 to 1.81]) after adjustment for age and sex. Separate analyses for stroke (odds ratio, 1.32 [CI, 0.99 to 1.77]) and transient ischemic attack (odds ratio, 1.56 [CI, 1.14 to 2.14]) showed no material difference in their relation to decreasing response to APC. The odds ratios for cerebrovascular disease according to varying levels of response to APC are presented in Table 2. Adjustment for presence of the factor V mutant allele did not substantially change the results; the adjusted odds ratio of cerebrovascular disease for each 1-unit decrease in response to APC was 1.43 (CI, 1.12 to 1.81). Table 2. Prevalence of Cerebrovascular Disease and Myocardial Infarction by Levels of Response to Activated Protein C* Response to APC was not associated with myocardial infarction; the odds ratio for response to APC as a continuous variable was 1.10 (CI, 0.89 to 1.37) (Table 2). Factor V Mutation Heterozygosity for the factor V mutation was present in 5% of controls (11 of 222), 6% of patients with cerebrovascular disease (6 of 107), and 4% of patients with myocar

The Adult Netherlands Twin Register: twenty-five years of survey and biological data collection.

Over the past 25 years, the Adult Netherlands Twin Register (ANTR) has collected a wealth of information on physical and mental health, lifestyle, and personality in adolescents and adults. This article provides an overview of the sources of information available, the main research findings, and an outlook for the future. Between 1991 and 2012, longitudinal surveys were completed by twins, their parents, siblings, spouses, and offspring. Data are available for 33,957 participants, with most individuals having completed two or more surveys. Smaller projects provided in-depth phenotyping, including measurements of the autonomic nervous system, neurocognitive function, and brain imaging. For 46% of the ANTR participants, DNA samples are available and whole genome scans have been obtained in more than 11,000 individuals. These data have resulted in numerous studies on heritability, gene x environment interactions, and causality, as well as gene finding studies. In the future, these studies will continue with collection of additional phenotypes, such as metabolomic and telomere length data, and detailed genetic information provided by DNA and RNA sequencing. Record linkage to national registers will allow the study of morbidity and mortality, thus providing insight into the development of health, lifestyle, and behavior across the lifespan.

Association of plasma fibrinogen levels with coronary artery disease, smoking and inflammatory markers

The plasma level of fibrinogen is associated with the risk of ischaemic heart disease (IHD) and the severity of atherosclerosis. It has been suggested that an increased plasma level of fibrinogen is a coronary risk indicator because it reflects the inflammatory condition of the vascular wall. An inflamed vascular wall may increase the production of the cytokines interleukin 6 (IL6), interleukin 1-beta (IL1-beta), and tumour necrosis factor alpha(TNF-alpha), which have a major role in the regulation of synthesis in the liver of acute phase proteins, including fibrinogen. Smoking has also been reported to increase the levels of fibrinogen and C-reactive protein (CRP). This may indicate that smoking induces an inflammatory reaction, probably of the pulmonary bronchi and alveolae. Therefore, we anticipated that with both types of inflammation the levels of acute phase proteins and cytokines would be related. We have investigated the contribution of inflammation to the plasma levels of fibrinogen in 34 patients with severe coronary artery disease (CAD) and 30 healthy controls comparable for age and smoking habits. We did not find a parallel in the effects of smoking and ischaemic heart disease on the plasma levels of fibrinogen, CRP, IL6, IL1-beta and TNF-alpha. Cardiovascular disease had its most important effect on the plasma fibrinogen level, while smoking appeared to increase the CRP levels, while both CAD and smoking seemed to affect the IL6 levels. Our results indicate that both smoking and CAD induce an inflammatory condition but that the increase of plasma levels of different inflammatory markers is complex. Although the acute phase reaction is the main regulatory mechanism of fibrinogen, the increase of fibrinogen in our group of CAD patients could not be fully explained by increased inflammation.

Circadian Variation of Fibrinolytic Activity in Blood

Approximately 35 years ago, it was discovered that spontaneous fibrinolytic activity in blood showed a sinusoidal variation with a period of 24 h; it increased severalfold during the day, reaching a peak at 6:00 p.m. and then dropped to trough levels at 3:00-4:00 a.m. The range of the fluctuation and the 24-h mean levels were highly reproducible within an individual; moreover, the timing of the oscillation was remarkably consistent among individuals, with a fixed phase relationship to external clock time. The biorhythm could not be accounted for simply by variations in physical activity, body posture, or sleep/wake schedule. Gender, ethnic origin, meals, or resting levels of blood fibrinolytic activity also did not influence the basic features of the rhythm. Older subjects, compared to younger ones, showed a blunted diurnal increase in fibrinolytic activity in blood. Recent studies have established that, of the known components of the fibrinolytic system, only tissue-type plasminogen activator (tPA) and its fast-acting inhibitor, plasminogen activator inhibitor-1 (PAI-1), show a marked circadian variation in plasma. In contrast, levels of plasminogen, alpha 2-antiplasmin, urinary-type plasminogen activator, and a reversible tPA inhibitor vary little or none during the 24 h. Quenching antibodies to tPA have shown that the circadian rhythm of fibrinolytic activity in blood is due exclusively to changes in tPA activity. However, the 24-h fluctuation of plasma tPA activity is phase shifted in relation to the rhythm of immunoreactive tPA, but shows a precise phase inversion with respect to the 24-h variation of PAI-1 activity and antigen. Therefore, plasma tPA activity, as currently measured in vitro, is tightly and inversely related to the levels of PAI-1 throughout the 24-h cycle. The factors controlling the rhythmicity of plasma PAI-1 are not fully elucidated but probably involve a humoral mechanism; changes in endothelial function, circulating platelet release products, corticosteroids, catecholamines, insulin, activated protein C, or hepatic clearance do not appear to be responsible. Shift workers on weekly shift rotations show a disrupted 24-h rhythm of plasma tPA and PAI-1. In acute and chronic diseases, the circadian rhythmicity of fibrinolytic activity may show a variety of alterations, affecting the 24-h mean, the amplitude, or the timing of the fluctuation. It is advisable, therefore to define the 24-h pattern of plasma tPA and PAI-1 in patient groups, before levels based on a single blood sampling time are compared to those of a control population.(ABSTRACT TRUNCATED AT 400 WORDS)

Effect of low-dose heparin on urinary albumin excretion in insulin-dependent diabetes mellitus

We investigated the effect of heparin on urinary albumin excretion in patients with insulin-dependent diabetes mellitus. 39 patients with persistent urinary albumin excretion of 30-300 mg/24 h were randomly treated for 3 months with subcutaneous injections twice daily of isotonic saline, 5000 IU unfractionated heparin, or 2000 anti-Xa IU low-molecular-weight heparin. Unfractionated and low-molecular-weight heparin induced a significant reduction in urinary albumin excretion (p = 0.04 and p = 0.004). The mechanism and clinical relevance is unknown but deserve further attention.