Malene R. Andersen

Haemostatic reference intervals in pregnancy.

Haemostatic reference intervals are generally based on samples from non-pregnant women. Thus, they may not be relevant to pregnant women, a problem that may hinder accurate diagnosis and treatment of haemostatic disorders during pregnancy. In this study, we establish gestational age-specific reference intervals for coagulation tests during normal pregnancy. Eight hundred one women with expected normal pregnancies were included in the study. Of these women, 391 had no complications during pregnancy, vaginal delivery, or postpartum period. Plasma samples were obtained at gestational weeks 13-20, 21-28, 29-34, 35-42, at active labor, and on postpartum days 1 and 2. Reference intervals for each gestational period using only the uncomplicated pregnancies were calculated in all 391 women for activated partial thromboplastin time (aPTT), fibrinogen, fibrin D-dimer, antithrombin, free protein S, and protein C and in a subgroup of 186 women in addition for prothrombin time (PT), Owren and Quick PT, protein S activity, and total protein S and coagulation factors II, V, VII, VIII, IX, X, XI, and XII. The level of coagulation factors II, V, X, XI, XII and antithrombin, protein C, aPTT, PT remained largely unchanged during pregnancy, delivery, and postpartum and were within non-pregnant reference intervals. However, levels of fibrinogen, D-dimer, and coagulation factors VII, VIII, and IX increased markedly. Protein S activity decreased substantially, while free protein S decreased slightly and total protein S was stable. Gestational age-specific reference values are essential for the accurate interpretation of a subset of haemostatic tests during pregnancy, delivery, and puerperium.

The Direct Antiatherogenic Effect of Estrogen Is Present, Absent, or Reversed, Depending on the State of the Arterial Endothelium A Time Course Study in Cholesterol-Clamped Rabbits

BACKGROUND This study further investigated the relationship between estrogen, arterial endothelium, and nitric oxide (NO) in cholesterol-clamped rabbits. METHODS AND RESULTS Rabbits were ovariectomized, balloon-injured in the thoracic aorta, and grouped to receive cholesterol-enriched chow together with either 17beta-estradiol or vehicle for 1, 2, 4, or 8 weeks. In the undamaged aorta, cholesterol accumulation of the placebo rabbits was significantly increased from week 4 to 8 (P<0.001). This increase was almost completely inhibited by estrogen (P<0.001). In the balloon-injured aorta, the estrogen and placebo rabbits accumulated similar amounts of cholesterol in the reendothelialized areas. In the deendothelialized areas, the estrogen group surprisingly accumulated significantly more cholesterol than the placebo group. This difference was apparent from week 2 and became significant at week 8 (P<0.01). Circulating nitrite/nitrate were significantly increased by estrogen at weeks 1, 2, and 4 but not at week 8. Similarly, in additional experiments, basal NO release was significantly higher in estrogen-treated than in placebo-treated rabbits after 4 (P<0.05) but not after 8 weeks. Stimulated NO release and endothelial NO synthase activity did not differ between groups. Mononuclear-endothelial cell binding was reduced by 50% by estrogen after 4 weeks (P<0.05). This difference, however, was abolished by coadministration of N(G)-nitro-L-arginine methyl ester, an inhibitor of NO production. CONCLUSIONS The direct antiatherogenic effect of estrogen was present, absent, or reversed, depending on the state of the arterial endothelium, and preceded by a transient increase in NO production followed by a reduced mononuclear-endothelial cell binding.

Smoking Cessation Early in Pregnancy and Birth Weight, Length, Head Circumference, and Endothelial Nitric Oxide Synthase Activity in Umbilical and Chorionic Vessels : An Observational Study of Healthy Singleton Pregnancies

Background— Reduced production of the vasodilator nitric oxide (NO) in fetal vessels in pregnant smokers may lower the blood flow to the fetus and result in lower birth weight, length, and head circumference. The present study measured endothelial NO synthase (eNOS) activity in fetal umbilical and chorionic vessels from nonsmokers, smokers, and ex-smokers and related the findings to the fetal outcome. Methods and Results— Of 266 healthy, singleton pregnancies, 182 women were nonsmokers, 43 were smokers, and 41 stopped smoking early in pregnancy. eNOS activity and concentration were quantified in endothelial cells of the fetal vessels. Cotinine, lipid profiles, estradiol, l-arginine, and dimethylarginines that may affect NO production were determined in maternal and fetal blood. Serum cotinine verified self-reported smoking. Newborns of smokers had a lower weight (P≤0.001) and a smaller head circumference (P≤0.041) and were shorter (P≤0.001) than newborns of nonsmokers and ex-smokers. eNOS activity in umbilical veins of smokers was 36% lower (P<0.001), eNOS concentration was 47% lower (P<0.001), and the fetal plasma level of high-density lipoprotein was 18% lower (P<0.001) than those of nonsmokers, whereas the same levels were found in umbilical veins from ex-smokers and nonsmokers. The same patterns in eNOS activity and concentration were found in umbilical arteries and chorionic vessels. Fetal plasma levels of estradiol, l-arginine, dimethylarginines, total cholesterol, and triglycerides were similar for nonsmokers, smokers, and ex-smokers. Conclusions— The findings suggest that maternal smoking reduces eNOS activity in the fetal vascular bed, contributing to retarded fetal growth caused by the reduction of vasodilatory capacity, and suggest that smoking cessation early in pregnancy prevents these effects in newborns.

Laboratory reference intervals during pregnancy, delivery and the early postpartum period

Abstract Background: Physiological changes during pregnancy may affect laboratory parameters. Reference values based on samples from non-pregnant women are not necessarily useful for clinical decisions during pregnancy. There is a need to establish reference values during pregnancy in order to recognize pathological conditions. Methods: Eight hundred and one women with expected normal pregnancies were included in the study. Of these, 391 had no complications during pregnancy, delivery, or the early postpartum period. Blood samples were obtained at gestational weeks 13–20, 21–28, 29–34, 35–42, at labor, and 1 and 2 days postpartum. Reference intervals were calculated for 36 tests as recommended by the International Federation of Clinical Chemistry and Laboratory Medicine. Results: Many tests showed such large variations indicating that gestational age-specific reference intervals were necessary. Other tests had different but stable values when compared to non-pregnant women. A minor decrease in albumin levels was observed. This was not only due to pregnancy-associated hemodilution, since other components with the same or a larger molecular diameter did not show a similar decrease. Many tests exhibited a broad distribution around vaginal delivery and in the early postpartum period. Conclusions: Only a few parameters were unaffected during uncomplicated pregnancy, delivery, and the early postpartum period suggesting that implementation of gestational age-specific reference intervals is necessary. Clin Chem Lab Med 2010;48:237–48.

Provision of healthy school meals does not affect the metabolic syndrome score in 8-11-year-old children, but reduces cardiometabolic risk markers despite increasing waist circumference.

An increasing number of children are exhibiting features of the metabolic syndrome (MetS) including abdominal fatness, hypertension, adverse lipid profile and insulin resistance. Healthy eating practices during school hours may improve the cardiometabolic profile, but there is a lack of evidence. In the present study, the effect of provision of school meals rich in fish, vegetables and fibre on a MetS score (primary outcome) and on individual cardiometabolic markers and body composition (secondary outcomes) was investigated in 834 Danish school children. The study was carried out as a cluster-randomised, controlled, non-blinded, cross-over trial at nine schools. Children aged 8-11 years received freshly prepared school lunch and snacks or usual packed lunch from home (control) each for 3 months. Dietary intake, physical activity, cardiometabolic markers and body composition were measured at baseline and after each dietary period. The school meals did not affect the MetS score (P= 1.00). However, it was found that mean arterial pressure was reduced by 0.4 (95% CI 0.0, 0.8) mmHg (P= 0.04), fasting total cholesterol concentrations by 0.05 (95% CI 0.02, 0.08) mmol/l (P= 0.001), HDL-cholesterol concentrations by 0.02 (95% CI 0.00, 0.03) mmol/l, TAG concentrations by 0.02 (95% CI 0.00, 0.04) mmol/l (both P< 0.05), and homeostasis model of assessment-insulin resistance by 0.10 (95% CI 0.04, 0.16) points (P= 0.001) compared with the control diet in the intention-to-treat analyses. Waist circumference increased 0.5 (95% CI 0.3, 0.7) cm (P< 0.001), but BMI z-score remained unaffected. Complete-case analyses and analyses adjusted for household educational level, pubertal status and physical activity confirmed the results. In conclusion, the school meals did not affect the MetS score in 8-11-year-olds, as small improvements in blood pressure, TAG concentrations and insulin resistance were counterbalanced by slight undesired effects on waist circumference and HDL-cholesterol concentrations.

Circulating ACE is a predictor of weight loss maintenance not only in overweight and obese women, but also in men.

BACKGROUND:Circulating angiotensin-converting enzyme (ACE) was identified as a predictor of weight loss maintenance in overweight/obese women of the Diogenes project.OBJECTIVE:To investigate whether ACE acted also as a predictor in men of the Diogenes study and to compare it with that in women.DESIGN:Subjects, who lost ⩾8% of body weight induced by low-caloric diet in an 8-week weight loss period, were assigned to weight loss maintenance with dietary intervention for 6 months.SUBJECTS:125 overweight/obese healthy men from eight European countries who completed whole intervention.MEASUREMENTS:Concentrations and activity of serum ACE at baseline and after the 8-week weight loss, in addition to anthropometric and physiological parameters.RESULTS:Serum ACE concentration decreased by 11.3±10.6% during the weight loss period in men. A greater reduction is associated with less body weight regain during the maintenance period (r=0.227, P=0.012). ACE change was able to predict a weight regain ⩽20% after 6 months, with an odds ratio of 1.59 (95% confidence interval (CI): 1.09–2.33, P=0.016) for every 10% reduction, which was independent of body mass index and weight loss. The prediction power was weaker in men than in women, but without a significant sex difference (P=0.137). In pooled subjects (N=218), the odds ratio was 1.96 (95% CI: 1.46–2.64, P<0.001).CONCLUSIONS:A greater reduction of ACE during weight loss is favorable for weight maintenance in both men and women. This can offer useful information for personalized advice to improve weight loss maintenance. It also confirms the role of ACE in the metabolic pathways of weight regulation.

Antiatherogenic effects of oleanolic acid in apolipoprotein E knockout mice

Oleanolic acid (OA) is a plant triterpenoid steroid with potentially antiatherogenic properties. We investigated whether OA affected atherosclerosis development and vascular function in apolipoprotein E knockout (ApoE(-/-)) mice. ApoE(-/-) mice were fed a high cholesterol Western-type diet in combination with OA (100 mg/kg/day), fluvastatin (5 mg/kg/day) or vehicle, with wild type (WT) mice serving as controls. After 8 weeks of treatment atherosclerotic plaque areas in the aortic arch and plasma lipid concentrations were determined. Vasoconstriction and relaxation of the proximal part of aorta were investigated in vitro. Inducible nitric oxide synthase (iNOS) was visualized using immunoblotting. As opposed to WT and fluvastatin- and vehicle-treated mice, OA-fed ApoE(-/-) mice gained no weight during the treatment period. Plasma concentrations of total-cholesterol and triglyceride were not significantly reduced by OA- or fluvastatin treatment. Plaque area of vehicle-treated mice was 25%, but only 14% in OA- and 19% in fluvastatin-treated mice. As compared to WT, vasoconstriction to phenylephrine was attenuated in ApoE(-/-) mice. The NOS inhibitor asymmetric dimethylarginine (ADMA) enhanced phenylephrine constriction, but significantly more so in vehicle- and fluvastatin-treated than in OA-treated and WT mice. Relaxation to acetylcholine was only slightly attenuated in ApoE(-/-) mice and not affected by OA or fluvastatin treatment. ADMA abolished acetylcholine relaxation almost completely. In ApoE(-/-) mice iNOS expression was reduced by OA treatment. In conclusion OA exerts potent antiatherogenic effects independent of plasma lipid levels and without major changes in eNOS-mediated acetylcholine relaxation. However, OA reduced iNOS expression possibly altering vascular reactivity to phenylephrine.

Blood Profile of Proteins and Steroid Hormones Predicts Weight Change after Weight Loss with Interactions of Dietary Protein Level and Glycemic Index

Background Weight regain after weight loss is common. In the Diogenes dietary intervention study, high protein and low glycemic index (GI) diet improved weight maintenance. Objective To identify blood predictors for weight change after weight loss following the dietary intervention within the Diogenes study. Design Blood samples were collected at baseline and after 8-week low caloric diet-induced weight loss from 48 women who continued to lose weight and 48 women who regained weight during subsequent 6-month dietary intervention period with 4 diets varying in protein and GI levels. Thirty-one proteins and 3 steroid hormones were measured. Results Angiotensin I converting enzyme (ACE) was the most important predictor. Its greater reduction during the 8-week weight loss was related to continued weight loss during the subsequent 6 months, identified by both Logistic Regression and Random Forests analyses. The prediction power of ACE was influenced by immunoproteins, particularly fibrinogen. Leptin, luteinizing hormone and some immunoproteins showed interactions with dietary protein level, while interleukin 8 showed interaction with GI level on the prediction of weight maintenance. A predictor panel of 15 variables enabled an optimal classification by Random Forests with an error rate of 24±1%. A logistic regression model with independent variables from 9 blood analytes had a prediction accuracy of 92%. Conclusions A selected panel of blood proteins/steroids can predict the weight change after weight loss. ACE may play an important role in weight maintenance. The interactions of blood factors with dietary components are important for personalized dietary advice after weight loss. Registration ClinicalTrials.gov NCT00390637

Metabolic syndrome, circulating RBP4, testosterone, and SHBG predict weight regain at 6 months after weight loss in men

Weight loss helps reduce the symptoms of the metabolic syndrome (MetS) in the obese, but weight regain after active weight loss is common. The changes and predictive role of circulating adipokines and sex hormones for weight regain in men during dietary intervention, and also the effect of basal MetS status on weight regain, were investigated.

Eicosapentaenoic Acid and Docosahexaenoic Acid in Whole Blood Are Differentially and Sex-Specifically Associated with Cardiometabolic Risk Markers in 8–11-Year-Old Danish Children

n-3 long-chain polyunsaturated fatty acids improve cardiovascular risk markers in adults. These effects may differ between eicosapentaenoic acid (EPA, 20∶5n-3) and docosahexaenoic acid (DHA, 22∶6n-3), but we lack evidence in children. Using baseline data from the OPUS School Meal Study we 1) investigated associations between EPA and DHA in whole blood and early cardiometabolic risk markers in 713 children aged 8–11 years and 2) explored potential mediation through waist circumference and physical activity and potential dietary confounding. We collected data on parental education, pubertal stage, 7-day dietary records, physical activity by accelerometry and measured anthropometry, blood pressure, and heart rate. Blood samples were analyzed for whole blood fatty acid composition, cholesterols, triacylglycerol, insulin resistance by the homeostatic model of assessment (HOMA-IR), and inflammatory markers. Whole blood EPA was associated with a 2.7 mmHg (95% CI 0.4; 5.1) higher diastolic blood pressure per weight% EPA, but only in boys. Heart rate was negatively associated with both EPA and DHA status (P = 0.02 and P = 0.002, respectively). Whole blood EPA was negatively associated with triacylglycerol (P = 0.003) and positively with total cholesterol, low density and high density lipoprotein (HDL) cholesterol and HDL:triacylglycerol (all P<0.01) whereas DHA was negatively associated with insulin and HOMA-IR (P = 0.003) and tended to be negatively associated with a metabolic syndrome-score (P = 0.05). Adjustment for waist circumference and physical activity did not change the associations. The association between DHA and HOMA-IR was attenuated but remained after adjustment for fiber intake and none of the other associations were confounded by dietary fat, protein, fiber or energy intake. This study showed that EPA status was negatively associated with triacylglycerol and positively with cholesterols whereas DHA was negatively associated with insulin resistance, and both were inversely associated with heart rate in children. The sex-specific associations with blood pressure confirm our previous findings and warrant further investigation.