P.L. van Haelst
University of Groningen
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Featured researches published by P.L. van Haelst.
European Journal of Clinical Nutrition | 2004
Wje Bemelmans; Joop D. Lefrandt; E.J.M. Feskens; P.L. van Haelst; Jan Broer; B Meyboom-de Jong; Jf May; Jan W. Cohen Tervaert; Andries J. Smit
Objective: To investigate the effects of increased alpha-linolenic acid (ALA)-intake on intima–media thickness (IMT), oxidized low-density lipoprotein (LDL) antibodies, soluble intercellular adhesion molecule-1 (sICAM-1), C-reactive protein (CRP), and interleukins 6 and 10.Design: Randomized double-blind placebo-controlled trial.Subjects: Moderately hypercholesterolaemic men and women (55±10 y) with two other cardiovascular risk factors (n=103).Intervention: Participants were assigned to a margarine enriched with ALA (fatty acid composition 46% LA, 15% ALA) or linoleic acid (LA) (58% LA, 0.3% ALA) for 2 y.Results: Dietary ALA intake was 2.3 en% among ALA users, and 0.4 en% among LA users. The 2-y progression rate of the mean carotid IMT (ALA and LA: +0.05 mm) and femoral IMT (ALA:+0.05 mm; LA:+0.04 mm) was similar, when adjusted for confounding variables. After 1 and 2 y, ALA users had a lower CRP level than LA users (net differences −0.53 and −0.56 mg/l, respectively, P<0.05). No significant effects were observed in oxidized LDL antibodies, and levels of sICAM-1, interleukins 6 and 10.Conclusions: A six-fold increased ALA intake lowers CRP, when compared to a control diet high in LA. The present study found no effects on markers for atherosclerosis.Sponsorship: The Dutch ‘Praeventiefonds’.
European Journal of Internal Medicine | 2001
P.L. van Haelst; J.J. van Doormaal; Jf May; Rob Gans; Harry J.G.M. Crijns; J. W. Cohen Tervaert
BACKGROUND Treatment of hypercholesterolaemia with HMG-CoA reductase inhibitors results in an earlier reduction of morbidity and mortality than expected from trials using conventional cholesterol-lowering therapies. Possible explanations for this effect include stimulation of angiogenesis, improvement of endothelial function, plaque stabilisation, inhibition of coagulation and/or thrombocyte aggregation and inhibition of the inflammatory response associated with atherosclerosis. METHODS We investigated whether statins exert their effects by inhibition of endothelial activation, inflammation and/or monocyte/macrophage activation by measuring plasma levels of soluble cell adhesion molecules, neopterin and C-reactive protein upon treatment with fluvastatin for a period of 12 months in patients with established atherosclerosis and hypercholesterolaemia. RESULTS Blood samples were taken at baseline and at 3 and 12 months after starting treatment with fluvastatin 80 mg daily. Upon treatment, a reduction of s-ICAM-1 (956.3+/-123.6 vs. 745.4+/-127.4 vs. 674.9+/-70.8 ng/ml, P<0.05) and s-E-selectin (58.6+/-6.7 vs. 47.0+/-6.1 vs. 44.9+/-3.2 ng/ml, P<0.01) was observed. In addition, levels of neopterin decreased, albeit transiently (7.1+/-0.7 vs. 6.0+/-0.5 vs. 6.5+/-0.8 nmol/l, P=0.02), suggesting a reduction in monocyte/macrophage activity. Moreover, we found a decrease in levels of C-reactive protein during follow-up (5.21+/-2.0 vs. 3.18+/-0.7 vs. 1.95+/-0.3 mg/l, P<0.05), compatible with a reduction in inflammatory activity. CONCLUSION We conclude that statins have a combined beneficial effect on monocyte/macrophage activity, endothelial function and systemic inflammatory activity.
Netherlands Heart Journal | 2009
Douwe J. Mulder; P.L. van Haelst; Reindert Graaff; Reinold Gans; F. Zijlstra; Andries J. Smit
Background.ST-elevation myocardial infarction (STEMI) is associated with increased inflammation and oxidative stress, enhancing the formation of advanced glycation endproducts (AGEs). These encompass a characteristic fluorescence pattern, which can be non-invasively measured as skin autofluorescence (AF). In this study we investigate whether skin AF is elevated in STEMI, its association with inflammatory and glycaemic stress and its predictive value for future events.Methods.Skin AF was measured in 88 STEMI patients (mean age 64±13 years) within 72 hours and around six months after discharge, in 81 stable coronary artery disease (sCAD) patients (64±10 years), and in 32 healthy controls (63±11 years). The cumulative one-year incidence of all-cause mortality and hospitalisation for myocardial infarction or heart failure was documented.Results.Skin AF was significantly higher in STEMI compared with sCAD and controls, irrespective of confounders, and was associated with HbA1c and C-reactive protein. Skin AF decreased significantly in STEMI patients, when measured >200 days after discharge. In STEMI patients, skin AF above the median was predictive of future events (hazard ratio 11.6, 95% CI 1.5 to 90.8, p=0.019).Conclusion.Skin AF is elevated in STEMI, is associated with inflammation and glycaemic stress, and predicts future major adverse cardiac events. (Neth Heart J 2009;17:162–8.)
Clinical Science | 2003
P.L. van Haelst; van Jasper Doormaal; Folkert W. Asselbergs; Am van Roon; Nic J. G. M. Veeger; Mm Henneman; Andries J. Smit; Jwc Tervaert; Jf May; Reinold Gans
Atherosclerosis is characterized by a low-grade systemic inflammatory response and endothelial dysfunction. The aim of the present study was to investigate a possible relationship between systemic markers of inflammation, serum markers of endothelial activation and endothelium-dependent vasodilatation in a group of high-risk patients, and to evaluate the effects of intervention with high doses of simvastatin on these parameters. In patients with heterozygous familial hypercholesterolaemia, without atherosclerotic events, flow-mediated vasodilatation (FMD) of the brachial artery was measured after a wash-out period for lipid-lowering drugs (baseline) and after 6 weeks of treatment with simvastatin 80 mg daily. Levels of C-reactive protein (CRP), soluble intercellular cell-adhesion molecule (s-ICAM) and soluble E-selectin (s-E-selectin) were determined at baseline and again after 6 weeks and 12 months of therapy. A total of 35 subjects participated in the study (mean age 42 years; 60% male). When divided into tertiles according to FMD (<3.9%, 3.9-9.0% and >9.0%), no differences in levels of CRP, s-ICAM-1 and/or s-E-selectin were detected between the groups. Moreover, no changes in FMD, levels of CRP or levels of s-ICAM-1 and/or s-E-selectin were found during treatment with simvastatin. We conclude that endothelial function, as reflected by FMD, does not seem to be related to markers of inflammation in familial hypercholesterolaemia subjects at high risk of, but without clinically overt signs of, atherosclerosis. Moreover, aggressive lipid-lowering therapy with simvastatin does not result in improved endothelial function or in a reduction of markers of inflammation in these patients.
International Journal of Cardiology | 2001
P.L. van Haelst; J.R. Timmer; Harry J.G.M. Crijns; H.F. Kauffman; Rob Gans; J.J. van Doormaal
BACKGROUND Unstable coronary syndromes, such as acute myocardial infarction and unstable angina pectoris are mostly due to rupture of an atherosclerotic plaque. Recently mast cells were found to participate actively in the inflammatory process of atherosclerosis by excreting proteolytic and pro-inflammatory substances with the ability to cause plaque instability and rupture. Mast cell activity can be determined by measuring serum levels of tryptase, as has been demonstrated in patients with anaphylaxis and mastcytosis. HYPOTHESIS Acute coronary events (acute myocardial infarction and unstable angina pectoris) are associated with increased mast cell activity, reflected by elevated serum tryptase levels. METHODS Serum levels of tryptase were determined in the following three groups of patients: 13 patients with acute myocardial infarction, 10 patients with unstable angina pectoris, and 14 patients without ischaemic cardiovascular disease who were used as controls. Patients with known IgE mediated allergic diseases and/or anti-histaminical drugs were excluded. RESULTS The groups were comparable for sex, blood pressure, smoking and cholesterol levels. The controls tended to be younger (P=0.05). Levels of tryptase did not differ between patients with acute myocardial infarction (7.9+/-4.6 microg/l), unstable angina pectoris (6.0+/-2.1 microg/l) or controls (6.9+/-4.1 microg/l), nor could a relation with levels of C-reactive protein be demonstrated. CONCLUSION Serum levels of tryptase are not elevated in patients with acute coronary syndromes. This implies that increased mast cell activity, if any, in unstable coronary syndromes is not reflected systemically. Other, more specific methods will be needed to determine the activity of the mast cell in vivo.
Clinical and Experimental Immunology | 2004
P.L. van Haelst; J. W. Cohen Tervaert; J. Bijzet; C. Baljé‐Volkers; Jf May; B. Langeveld; Rob Gans
Acute coronary syndromes (ACS) are associated with inflammation resulting from monocyte activation. We sought for differences in the production of pro‐ and anti‐inflammatory cytokines by monocytes from patients with ACS. C‐reactive protein (CRP) and neopterin were measured in 22 patients with acute coronary syndromes, 50 patients with stable vascular disease and 22 healthy controls. Production of tumour necrosis factor (TNF)‐α and interleukin (IL)‐10 was determined after, respectively, 6 and 24 h of incubation of full blood with lipopolysaccharide (LPS). Levels of CRP [median, interquartile range (IQR)][1·5 mg/l (0·8–4·5) ACS patient versus 2·1 (0·9–3·6) stable disease versus 0·4 (0·3–1·2) healthy controls] (P < 0·001) and neopterin [7·4 nmol/l (6·0–8·7) ACS patient versus 7·1(6·0–8·9) stable disease versus 6·4 (5·6–7·3) healthy controls] (P = 0·07) were higher in both the patient groups. IL‐10 production after LPS stimulation was greatly reduced in patients with acute coronary syndromes (16 175 pg/ml, 7559–28 470 pg/ml) as opposed to patients with stable disease (28 379 pg/ml, 12 601–73 968 pg/ml) and healthy controls (63 830 pg/ml, 22 040–168 000 pg/ml) (P = 0·003). TNF‐α production was not significantly different between the groups [7313 pg/ml (4740–12 615) ACS patient versus 11 002 (5913–14 190) stable disease versus 8229 (5225–11 364) healthy controls] (P = 0·24). Circulating monocytes in unstable coronary syndromes produce equal amounts of TNF‐α but less IL‐10 after stimulation with LPS in vitro as compared with healthy controls. We hypothesize that, in acute coronary syndromes, the production proinflammatory cytokines is not counterbalanced by anti‐inflammatory cytokines such as IL‐10.
European Journal of Vascular and Endovascular Surgery | 2003
P.L. van Haelst; J. W. Cohen Tervaert; Pp van Geel; N.J.G.M. Veeger; O. Gurné; Rob Gans; W. H. Van Gilst
OBJECTIVE to examine the effect of angiotensin converting enzyme inhibition (ACEI) on soluble intercellular adhesion molecule 1 (sICAM-1) and C-reactive protein (CRP) in patients requiring coronary artery bypass grafting (CABG). METHOD subgroup analysis of 42 patients randomised to Quinapril (40 mg daily determined) and 45 to placebo. sICAM-1 and CRP were > or = 4 weeks before and 1 year after surgery. RESULTS there was no difference in sICAM-1 at baseline (142.2 microg/L vs 136.6 microg/L). There was significant reduction in s-ICAM-1 in patients receiving quinapril (142.2+/-10.8 microg/L vs 125.6+/-9.4 microg/L, p<0.05) but not placebo (136.6+/-10.2 microg/L vs 131.2+/-11.7 microg/L, p=NS). Levels of C-reactive protein remained unchanged in both groups (3.70+/-0.85 vs 2.73+/-0.32 mg/L, 2.85+/-0.48 vs 3.16+/-0.50 mg/L). CONCLUSIONS ACEI reduces sICAM-1 in patients undergoing CABG. The benefits of ACEI may partly be due to a reduction of the vascular inflammatory response.
International Reviews of Immunology | 2002
P.L. van Haelst; A. C. Muller Kobold; J.J. van Doormaal; J. W. Cohen Tervaert
Autoimmunity is suggested to play a pathogenetic role in premature atherosclerosis. Since atherosclerosis and vasculitis seem pathogenetically related, we hypothesized that ANCA, an important antibody in vasculitis, plays a role in atherosclerosis as well. We therefore investigated the prevalence of ANCA in patients with premature atherosclerosis and related the presence of these antibodies to levels of AECA and markers of inflammation. Methods & Results: In a cohort of 286 patients with premature atherosclerosis the prevalence of ANCA was 5.6% (16/286). All had perinuclear ANCA. More females were ANCA-positive (8M/8F vs. 200M/70F, p=0.03). In a nested case-control study, comparing the 16 ANCA-positive patients with 32 controls, levels of AECA were higher in the first (7.32±0.91U vs. 5.52±0.41U, p<0.05). Conclusion: ANCA does not seem to play a major role in premature atherosclerosis. Whether elevated levels of AECA in ANCA-positive patients with premature atherosclerosis reflect more extended vascular di...Autoimmunity is suggested to play a pathogenetic role in premature atherosclerosis. Since atherosclerosis and vasculitis seem pathogenetically related, we hypothesized that ANCA, an important antibody in vasculitis, plays a role in atherosclerosis as well. We therefore investigated the prevalence of ANCA in patients with premature atherosclerosis and related the presence of these antibodies to levels of AECA and markers of inflammation. Methods & Results: In a cohort of 286 patients with premature atherosclerosis the prevalence of ANCA was 5.6% (16/286). All had perinuclear ANCA. More females were ANCA-positive (8M/8F vs. 200M/70F, p=0.03). In a nested case-control study, comparing the 16 ANCA-positive patients with 32 controls, levels of AECA were higher in the first (7.32±0.91U vs. 5.52±0.41U, p<0.05). Conclusion: ANCA does not seem to play a major role in premature atherosclerosis. Whether elevated levels of AECA in ANCA-positive patients with premature atherosclerosis reflect more extended vascular disease remains to be determined.
Clinical Science | 2004
Folkert W. Asselbergs; Stefan H.J. Monnink; N.J.G.M. Veeger; Aj van Boven; P.L. van Haelst; Gillian A.J. Jessurun; van Wiekert Gilst; Ra Tio
Disturbed vasomotor function in coronary arteries has clinical importance in early stages of coronary artery disease (CAD), as it may contribute to the potential risk for an ischaemic coronary event. In the present study, we have investigated the relationship between coronary vasomotor function and the extent of CAD. The response to acetylcholine and nitrate infusion was assessed by quantitative coronary angiography. The extent of CAD was categorized into two groups: minor CAD (normal coronary arteries and vessel wall irregularities) and significant CAD (one-, two- and three-vessel disease). A total of 277 patients with stable angina pectoris, referred for a first diagnostic coronary angiography, were eligible for analysis (mean age 57 years, 61% male). The response to nitrate was significantly impaired in patients with significant CAD ( P <0.001). On the other hand, the response to acetylcholine was not different between the two groups ( P =0.12); however, a trend between the response to acetylcholine and the extent of CAD was observed in patients without a previous infarction ( P =0.07), which was a significant interaction variable. Furthermore, a significant relationship between coronary vasomotor response and the number of cardiovascular risk factors was observed ( P <0.05). In conclusion, in a heterogeneous group of patients, coronary vasomotor function measured by nitrate infusion was more strongly associated with the extent of CAD and the number of risk factors than the response to acetylcholine. These data suggest that, in patients with advanced atherosclerosis or multiple risk factors, the vasomotor dysfunction is not solely restricted to the endothelium.
Journal of Internal Medicine | 2002
P.L. van Haelst; Folkert W. Asselbergs; J.J. van Doormaal; Nic J. G. M. Veeger; Jf May; Paul Holvoet; Rob Gans; J. W. Cohen Tervaert
Abstract. van Haelst PL, Asselbergs FW, van Doormaal JJ, Veeger NJGM, May JF, Holvoet P, Gans ROB, Cohen Tervaert JW (University Hospital Groningen, Groningen, The Netherlands; University of Leuven, Leuven, Belgium). Antineutrophil cytoplasmatic antibodies in patients with premature atherosclerosis: prevalence and association with risk factors. J. Intern Med 2002; 251: 29–34.