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H Arnesen

Publications and source records attributed to H Arnesen.

At least 73 records · Page 4Linked to original sources
PubMed1997

Peroxidation of LDL from combined-hyperlipidemic male smokers supplied with omega-3 fatty acids and antioxidants.

The effects of marine omega-3 polyunsaturated fatty acids (FAs) and antioxidants on the oxidative modification of LDL were studied in a randomized, double-blind, placebo-controlled trial. Male smokers (n = 41) with combined hyperlipidemia were allocated to one of four groups receiving supplementation with omega-3 FAs (5 g eicosapentaenoic acid and docosahexaenoic acid per day), antioxidants (75 mg vitamin E, 150 mg vitamin C, 15 mg beta-carotene, and 30 mg coenzyme Q10 per day), both omega-3 FAs and antioxidants, or control oils. LDL and human mononuclear cells were isolated from the patients at baseline and after 6 weeks of supplementation. LDL was subjected to cell-mediated oxidation by the patients' own mononuclear cells, as well as to Cu(2+)-catalyzed and 2,2'-azobis-(2-amidinopropane hydrochloride) (AAPH)-initiated oxidation. Extent of LDL modification was measured as lag time, the formation rate of conjugated dienes (CDs), the maximum amount of CDs formed, formation of lipid peroxides, and the relative electrophoretic mobility of LDL on agarose gels. Dietary supplementation with omega-3 FAs increased the concentration of total omega-3 FAs in LDL and reduced the concentration of vitamin E in serum. The omega-3 FA-enriched LDL particles were not more susceptible to Cu(2+)-catalyzed, AAPH-initiated, or autologous cell-mediated oxidation than control LDL. In fact, enrichment with omega-3 FAs significantly reduced the formation rate of CDs when LDL was subjected to AAPH-induced oxidation. Supplementation with moderate amounts of antioxidants significantly increased the concentration of vitamin E in serum and increased the resistance of LDL to undergo Cu(2+)-catalyzed oxidation, measured as increased lag time, reduced formation of lipid peroxides, and reduced relative electrophoretic mobility compared with control LDL. Supplementation with omega-3 FAs/antioxidants showed oxidizability of LDL similar to that of control LDL and omega-3 FA-enriched LDL. In conclusion, omega-3 FAs neither rendered the LDL particles more susceptible to undergo in vitro oxidation nor influenced mononuclear cells' ability to oxidize autologous LDL, whereas moderate amounts of antioxidants protected LDL against oxidative modification.

Administration, Oral↗
PubMed1997

Prolonged thromboprophylaxis following hip replacement surgery--results of a double-blind, prospective, randomised, placebo-controlled study with dalteparin (Fragmin)

Discontinuation of thromboprophylaxis a few days after surgery may unmask delayed hypercoagulability and contribute to late formation of deep venous thrombosis (DVT). To investigate whether thromboprophylaxis should be prolonged beyond the hospital stay, a prospective, double-blind randomised study was conducted in 308 patients. All patients received initial thromboprophylaxis with dalteparin, dextran and graded elastic stockings. On day 7, patients were randomised to receive dalteparin (Fragmin) 5000 i.u. once daily, or placebo, for 4 weeks. All patients were subjected to bilateral venography, perfusion ventilation scintigraphy and chest X-ray on days 7 and 35. Patients with venographically verified proximal DVT on day 7 were withdrawn from the randomised study to receive anticoagulant treatment. The overall prevalence of DVT on day 7 was 15.9%. On day 35, the prevalence of DVT was 31.7% in placebo-treated patients compared with 19.3% in dalteparin-treated patients (p = 0.034). The incidence of DVT from day 7 to day 35 was 25.8% in the placebo-treated group versus 11.8% in the dalteparin-treated group (p = 0.017). The incidence of symptomatic pulmonary embolism (PE) from day 7 to day 35 was 2.8% in the placebo-treated group compared with zero in the dalteparin-treated group. This included one patient who died from PE. No patients experienced serious complications related to the injections of dalteparin or placebo. This study shows that prolonged thromboprophylaxis with dalteparin. 5000 IU, once daily for 35 days significantly reduces the frequency of DVT and should be recommended for 5 weeks after hip replacement surgery.

Adult↗
PubMed1996

Effect of dietary supplementation with n-3 fatty acids on coronary artery bypass graft patency.

Epidemiologic and experimental data suggest that a high dietary intake of long-chain polyunsaturated n-3 fatty acids may reduce the risk of atherothrombotic disease. In a randomized, controlled study, 610 patients undergoing coronary artery bypass grafting were assigned either to a fish oil group, receiving 4 g/day of fish oil concentrate, or to a control group. All patients received antithrombotic treatment, either aspirin or warfarin. Their diet and serum phospholipid fatty acid profiles were monitored. The primary end point was 1-year graft patency, which was assessed by angiography in 95% of patients. Vein graft occlusion rates per distal anastomoses were 27% in the fish oil group and 33% in the control group (odds ratio 0.77, 95% confidence interval, 0.60 to 0.99, p = 0.034). In the fish oil group, 43% of the patients had > or = 1 occluded vein graft(s) compared with 51% in the control group (odds ratio 0.72, 95% confidence interval, 0.51 to 1.01, p = 0.05). Moreover, in the entire patient group, there was a significant trend to fewer patients with vein graft occlusions with increasing relative change in serum phospholipid n-3 fatty acids during the study period (p for linear trend = 0.0037). Thus, in patients undergoing coronary artery bypass grafting, dietary supplementation with n-3 fatty acids reduced the incidence of vein graft occlusion, and an inverse relation between relative change in serum phospholipid n-3 fatty acids and vein graft occlusions was observed.

Aged↗
PubMed1996

Predictors of enhanced well-being after coronary artery bypass surgery.

OBJECTIVES: To assess patients' perception of the therapeutic outcome after coronary artery bypass surgery, and to find predictors for increased well-being. DESIGN: Self-administered questionnaires (Family APGAR and GHQ-30) were completed on admission and at the follow-up after 12 months, together with functional classification according to the NYHA index. SETTING: Ullevål University Hospital, Oslo, Norway, 1990-1992. SUBJECTS: Two hundred and thirteen patients with stable angina admitted for elective coronary artery bypass surgery. INTERVENTION: Elective coronary artery bypass surgery. MAIN OUTCOME MEASURES: Improved physical and psychosocial functioning after one year. RESULTS: One hundred and ninety-seven (92%) patients improved their NYHA class, while it remained stable or declined in 16 (8%) patients. Significantly fewer patients with mental distress were found at the follow-up than at the baseline examination (49 patients [23%] versus 80 patients [38%], respectively, P < 0.0001). One hundred and forty-six patients (69%) reported enhanced psychosocial well-being, while it was reduced (n = 60) or unchanged (n = 7) in 67 patients (31%). Predictors for improved psychosocial well-being following coronary artery bypass surgery were mental distress before surgery (odds ratio 2.8) and being a male patient (odds ratio 2.8). CONCLUSIONS: The majority of the patients reported significant improvement in their physical and psychosocial functioning one year after coronary artery bypass surgery. Mental distress and male sex were significant predictors of enhanced well-being. Questionnaires on psychosocial well-being such as the GHQ-30 may, in addition to health status measurements, offer additional useful information when coronary artery bypass surgery is considered.

Coronary Artery Bypass↗
PubMed1996

The effect of angiotensin II receptor antagonism with losartan on glucose metabolism and insulin sensitivity.

OBJECTIVE: To investigate the metabolic effects of losartan (Cozaar) in patients with essential hypertension. METHODS: Twenty patients with mild hypertension (office blood pressure > 140/95 mmHg and home diastolic blood pressure > 90 mmHg) were examined in a double-blind, placebo-controlled cross-over study of 4 weeks of treatment with 50-100 mg losartan. The effects on glucose metabolism were assessed by euglycaemic glucose clamp examinations [glucose disposal rate (GDR, mg/kg per min)] and oral glucose-tolerance tests (OGTT). RESULTS: Supine blood pressure was reduced from 146 +/- 3/90 +/- 3 mmHg on placebo to 134 +/- 4/83 +/- 3 mmHg on losartan and the difference was maintained during 120 min of insulin infusion and glucose clamping. GDR was 6.2 +/- 0.5 mg/kg per min on placebo and 6.4 +/- 0.5 mg/kg per min on losartan. The glucose and insulin responses (the area under the curve) during OGTT were similar with placebo and losartan (0.86 +/- 0.3 versus 0.88 +/- 0.4 and 341 +/- 60 versus 356 +/- 60, respectively; arbitary units). Serum cholesterol was 5.3 +/- 0.2 mmol/l on placebo and 5.1 +/- 0.2 mmol/l losartan treatment. High-density lipoprotein cholesterol and triglycerides were, respectively, 1.1 +/- 0.1 and 1.5 +/- 0.2 mmol/l with placebo, and 1.1 +/- 0.1 and 1.4 +/- 0.1 mmol/l with losartan treatment. CONCLUSION: In mildly hypertensive patients, selective angiotensin II receptor antagonism with losartan for 4 weeks lowers blood pressure at rest and during 120 min of glucose clamping, and has neutral effects on insulin sensitivity, glucose metabolism and serum lipids.

Adult↗
PubMed1996

Effect of angiotensin II receptor blockade on fibrinolysis during acute hyperinsulinemia in patients with essential hypertension.

We performed the present study to investigate indirectly the in vivo effects of angiotensin II on fibrinolysis and catecholamines by treatment with losartan, a selective angiotensin II type 1 receptor antagonist. The effects were evaluated in basal conditions as well as in two different models of acute hyperinsulinemia physiologically induced by oral glucose ingestion and by a euglycemic glucose clamp technique. Twenty subjects with moderate hypertension were included in a randomized, double-blind, placebo-controlled crossover study of 4-week treatment periods. Plasma levels of catecholamines, tissue plasminogen activator activity and antigen, and plasminogen activator inhibitor type 1 activity and antigen were unchanged in the basal state after 4 weeks of treatment. During both models of hyperinsulinemia, plasminogen activator inhibitor activity and antigen decreased significantly (both P<.001), and tissue plasminogen activator activity increased significantly (P<.Ol). Norepinephrine did not change during any of the procedures, whereas epinephrine increased significantly after 3 hours of the oral glucose tolerance test. Changes from baseline did not differ between the treatment and placebo regimens during the hyperinsulinemic procedures with regard to either of the fibrinolytic variables or the catecholamines. In conclusion, we could not demonstrate any effects of 4 weeks of treatment with losartan on plasma levels of fibrinolytic variables or catecholamines either in basal conditions or during acute hyperinsulinemia. However, the present findings do not preclude more direct effects of angiotensin II or involvement of other receptor subtypes on fibrinolysis.

Adult↗
PubMed1995

Increased activation of coagulation and formation of late deep venous thrombosis following discontinuation of thromboprophylaxis after hip replacement surgery.

Hip replacement surgery (HRS) is associated with a high frequency of deep vein thrombosis (DVT). At the same time there is a substantial systemic and local activation of coagulation. This study indicates that discontinuation of thromboprophylaxis one week after surgery may allow a second wave of coagulation and fibrinolysis activation to occur. An almost parallel increase in plasma TAT and D-dimer levels between the 6th and the 35th postoperative day may indicate late DVT formation. Repeated bilateral ascending venography is though to be necessary to evaluate the suitability of using selected activation markers of the coagulation and fibrinolytic systems as indices of DVT formation.

Aged↗
PubMed1995

Effect of long-term, moderate-dose supplementation with omega-3 fatty acids on monocyte procoagulant activity and release of interleukin-6 in patients with coronary artery disease.

The influence of a moderate dietary supplementation with omega-3 polyunsaturated fatty acids (omega-3 PUFAs) (3.4 g eicosapentaenoic and docosahexaenoic acids per day) for six months on lipopolysaccharide (LPS) stimulated monocyte procoagulant activity (PCA) was studied in two series of experiments, evaluating the plasma and cellular phases, respectively. In the first series, standard cryopreserved monocyte cultures were examined in heparin plasma of atherosclerotic patients (n = 24, 12 given omega-3 PUFAs, 12 controls). In the second series, monocytes from patients (n = 32, 16 given omega-3 PUFAs, 16 controls) were investigated in a standard plasma milieu. Plasma and monocytes were obtained from the test subjects before as well as after six months of omega-3 PUFA supplementation. Monocyte PCA, measured by the formation of fibrinopeptide A, was not significantly different when comparing plasma and monocytes from the subjects supplemented with omega-3 PUFAs with plasma and monocytes, respectively, from the control subjects. In the second series of experiments we also determined the LPS induced release of interleukin-6 (IL-6), which was not significantly different in the two groups. However, a strong correlation between the stimulated monocyte IL-6 release and PCA was demonstrated (r = 0.70, p = 0.00001), probably reflecting an individual inflammatory response pattern.

Arachidonic Acid↗
PubMed1995

Increased insulin sensitivity and fibrinolytic capacity after dietary intervention in obese women with polycystic ovary syndrome.

In overweight women with polycystic ovary syndrome (PCOS), increased insulin resistance has been observed. Since abdominal obesity is associated with impaired fibrinolytic capacity and elevated levels of plasminogen activator inhibitor (PAI-1) and since PAI-1 seems to be related to insulin resistance, we investigated the possible effects of dietary intervention on lipids, fibrinolysis, coagulation, and insulin sensitivity in obese PCOS women. Nine women aged 22 to 39 years (median weight, 97 kg) ate a protein-rich very-low-calorie diet (VLCD) (Nutrilett, Nycomed Pharma, Oslo, Norway; 421 kcal/d) for 4 weeks (part 1). After significant reductions of body fat (13%, P < .01), two of nine women achieved regular menstruation and became pregnant. Six of the remaining women continued on a conventional low-calorie diet (1,000 to 1,500 kcal/d) for the next 20 weeks (part 2), during which time they were generally able to preserve the body fat loss obtained in part 1 of the study. During part 1, significant reductions of total serum cholesterol (29%, P = .001) and fasting triglyceride ([TG] 31%, P < .05) levels were observed, as well as significant reductions of fasting glucose (6%, P < .05) and insulin (20%, P < .05). Insulin sensitivity (glucose disposal rate [GDR]) was increased by 93% (P < .05). After finishing part 2, insulin sensitivity was still significantly increased (86%, P < .05) and PAI-1 activity was significantly reduced (54%, P < .05). Moreover, overall fibrinolytic activity was significantly improved (serum D-dimer concentration increased by 75%, P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗
PubMed1995

Long-term metabolic effects of n-3 polyunsaturated fatty acids in patients with coronary artery disease.

The long-term metabolic effects of n-3 fatty acids were studied in patients with coronary artery disease. They were investigated before and 9 mo after bypass surgery. After postoperative randomization, 260 patients received 4 g fish-oil concentrate/d (approximately 3.4 g eicosapentaenoic and docosahexaenoic acids/d), whereas 251 patients comprised the control group. No group differences in the intake of energy and nutrients, apart from n-3 fatty acids, were discerned from dietary records. Compliance was affirmed by analyses of serum phospholipid fatty acids. Serum triglyceride concentrations were lowered by 19.1% in the fish-oil group, but no influence on the concentrations of cholesterol or apolipoproteins A-I and B-100 was seen. The concentrations of plasma glucose and serum insulin and C-peptide were not influenced by fish oil. The activity of liver enzymes increased slightly, but significantly, in the fish-oil group, whereas no group difference in the serum concentrations of thiobarbituric acid-reactive substances was observed. Thus, no adverse metabolic effects of long-term fish-oil supplementation assumed to be of clinical importance were seen.

Aged↗
PubMed1995

Long-term effects of n-3 polyunsaturated fatty acids on haemostatic variables and bleeding episodes in patients with coronary artery disease.

The long-term effects of fish-oil supplementation on haemostatic parameters and bleeding episodes were investigated in patients undergoing coronary artery bypass surgery. They were investigated before and 9 months after the operation. Following randomization postoperatively, 260 patients received 4 g fish-oil concentrate per day, whereas 251 patients comprised the control group. All patients received either aspirin (300 mg/day) or warfarin (international normalized ratio aimed at 2.5-4.2). Compliance was affirmed by determination of serum phospholipid fatty acids. No excess of bleeding episodes could be attributed to the use of fish oil, given in addition to either aspirin or warfarin. The supplementation of fish oil did not affect the bleeding time or plasma levels of beta-thromboglobulin, whereas an increase in the platelet count after the operation was slightly less pronounced in the fish-oil group. Apart from a small increase in PAI-1 antigen of borderline significance, no long-term effects by fish oil on parameters of coagulation and fibrinolysis were seen.

Aged↗
PubMed1995

Serum Lp(a) lipoprotein levels in patients with coronary artery disease and the influence of long-term n-3 fatty acid supplementation.

The serum levels of Lp(a) lipoprotein (Lp(a)) were determined preoperatively in 601 patients with coronary artery disease, undergoing bypass operations. Compared with a reference group of 99 apparently healthy individuals, the Lp(a) levels were higher in the patient group (7.7 mg dl-1 vs. 5.1 mg dl-1, p = 0.012). In the patient group, there was a weak, but significant negative correlation between the Lp(a) levels and age (r = -0.10, p = 0.017), and in both groups the women had higher Lp(a) levels than the men. In the patients we found no significant correlations between Lp(a) and other serum lipids or lipoproteins, nor between Lp(a) and variables in the fibrinolytic system. We investigated the long-term effects of supplementation with n-3 polyunsaturated fatty acids (n-3 PUFAs) on the Lp(a) concentrations. Postoperatively, in a randomized fashion, 280 of the patients received 4 g of an n-3 PUFA concentrate (containing > 85% of long-chain n-3 PUFAs) per day, whereas 269 patients comprised the control group. The fatty acids in serum phospholipids were monitored, and a significant increase in the phospholipid n-3 fatty acids was noted in the n-3 PUFA group, as opposed to the virtually unchanged amounts in the control group. The Lp(a) levels were determined again after 6 months, and, compared with the control group, n-3 PUFA supplementation had no overall effect on the serum Lp(a) levels.

Adult↗
PubMed1995

Risk factors for graft occlusion after coronary artery bypass grafting.

A cohort of 610 well-characterized patients undergoing coronary artery bypass grafting were followed through the first postoperative year. Graft patency was angiographically assessed in 578 (94.8%) of the patients on average 12.1 (SD 1.5) months postoperatively and was related to characteristics of grafts and patients. For internal mammary artery grafts the incidence of graft occlusion was higher in women than in men and was inversely related to body surface area. In multivariate analysis the influence of gender was no longer significant when adjusted for body surface area. With vein grafts the incidence of occlusion was inversely related to body surface area and was positively associated with ejection fraction. Occlusion of vein grafts was less common in patients treated with beta-blockers pre- and peroperatively.

Adult↗
PubMed1994

Influence of serum lipoprotein(a) and homocyst(e)ine levels on graft patency after coronary artery bypass grafting.

High serum levels of lipoprotein(a) and homocyst(e)ine are considered independent risk factors for atherothrombotic disease. In a prospective study in patients undergoing coronary artery bypass grafting, the preoperatively determined lipoprotein(a) and homocyst(e)ine levels were related to the frequency of 1-year graft occlusion. A cohort of 610 patients who underwent coronary artery bypass surgery was followed through the first postoperative year. Shunt angiography was performed in 581 patients (95%) at a mean of 12.1 +/- 1.5 months after the operation. The serum levels of lipoprotein(a) (n = 570) and homocyst(e)ine (n = 565) in patients with occluded internal mammary artery (IMA) grafts were not significantly different from the levels in those with open IMA grafts. Also, the serum lipoprotein(a) and homocyst(e)ine levels in patients with > or = 1 occluded vein graft were not significantly different from those in patients with all vein grafts patent. This study also determined the incidence of graft occlusion in quartiles of the lipoprotein(a) and homocyst(e)ine levels, respectively, and tested for linear trends. No significant trends in the incidence of graft occlusion were found, but the number of patients with vein graft occlusions was higher in the lowest quartile of lipoprotein(a) than that in the upper 3 quartiles (odds ratio, 1.82, 95% confidence interval, 1.21 to 2.74, p = 0.0025). Controlling for background variables in multivariate models only slightly modified the results. Thus, apart from an unexplained excess of vein graft occlusions in the lowest quartile of lipoprotein(a) levels, no association between the preoperative serum lipoprotein(a) or homocyst(e)ine levels and the frequency of 1-year graft occlusion could be demonstrated.

Aged↗
PubMed1994

Global fibrinolytic capacity assessed by the serum D-dimer test. Correlation between basal and stimulated values.

Evaluation of fibrinolytic capacity is mostly done after stimulation by venous occlusion (VO) or 1-desamino-8-d-arginine vasopressin (DDAVP), either with global tests or with measurements of the specific fibrinolytic components. The serum D-dimer test has recently been described as a global fibrinolytic test in unstimulated individuals, and related to different levels of fibrinolytic activity. In the present study, we have compared the levels of serum D-dimer and t-PA before and after VO in order to see if the unstimulated values reflect the fibrinolytic capacity after stimulation. Twenty-eight healthy individuals and 126 patients with different metabolic disorders and/or coronary heart disease were included. Blood was drawn in a fasting state between 8 and 10 a.m. before and after VO for determinations of serum D-dimer after standardized coagulation, and of t-PA activity and antigen. There was a 7-fold increase in the median levels obtained after VO both for serum D-dimer and t-PA activity, whereas the increase in t-PA antigen was about 2.5 fold. The correlation coefficients between the levels of serum D-dimer, t-PA activity and t-PA antigen before and after VO were 0.63 (p < 0.001), 0.72 (p < 0.001) and 0.23 (p < 0.05), respectively. We conclude that the basal levels of t-PA and serum D-dimer to a certain degree reflect the fibrinolytic capacity after stimulation. Thus, the unstimulated serum D-dimer test, which reflects both t-PA and PAI-1, could be recommended as a global screening method for evaluation of the fibrinolytic potential.

Adult↗