PubMed Health⌕ Search

Biomedical subjects

E Vahtera

Publications and source records attributed to E Vahtera.

At least 19 recordsLinked to original sources

Symptoms of chronic bronchitis, haemostatic factors, and coronary heart disease risk.

Positive association has been suggested between a variety of infections and coronary heart disease. Disturbances in blood coagulation system may form a link between infections and coronary heart disease. The aim of this study was to analyze whether chronic bronchitis, defined by the occurrence of symptoms, is associated with selected haemostatic factors in a cross-sectional population study of 2379 Finnish men and women aged between 45 and 64 years. Plasma fibrinogen level was significantly higher, 3.70 versus 3.35 g/l (P < 0.001) in men and 3.64 versus 3.44 g/l (P < 0.001) in women, among subjects with symptoms of chronic bronchitis than among those without symptoms. The association was independent of age, smoking, body mass index, physical exercise, and alcohol consumption. Also plasminogen was higher among men with symptoms than among those without but the difference disappeared after adjustment for age and smoking. Factor VII coagulant activity and factor VII antigen level did not differ between subjects with and without symptoms. Thus, fibrinogen may be associated with a possible mechanism to link chronic bronchitis to coronary heart disease risk, even though the causality of the association cannot be verified in a cross-sectional study.

Blood Coagulation Factors↗

Intra- and interindividual variability of hemostatic factors and traditional cardiovascular risk factors in a three-year follow-up.

Elucidation of the key role of thrombosis in cardiovascular disease events has arisen considerable interest in hemostatic factors and in the repeatability of their determinations. Data on long-term repeatability has, however, remained scanty. We examined twice 208 men and 265 women in North Karelia, eastern Finland. The baseline examination was a part of the FINRISK 1992 Hemostasis Study and the age-range of participants was between 45-64 years. The re-examination took place three years later in 1995. Both surveys followed the same protocol and were carried out during the same season. Spearman rank correlation coefficients between 1992 and 1995 measurements of fibrinogen, factor VII coagulant activity (FVII:C), factor VII antigen (FVII:Ag), and plasminogen were among men 0.72, 0.77, 0.46 and 0.56, respectively. For total cholesterol, HDL-cholesterol, triglycerides and diastolic blood pressure the corresponding coefficients were 0.74, 0.83, 0.66, and 0.54. In women, the coefficient of fibrinogen was lower than in men, 0.62, otherwise the results were similar. Of men belonging to the highest quarter of fibrinogen, FVII:C, FVII:Ag and plasminogen in 1992, 65%, 60%, 53% and 60% belonged to the highest quarter of respective distributions also in 1995. In women, the corresponding proportions were 64%, 65%, 46% and 58%. The modest repeatability of FVII:Ag and plasminogen was mainly due to the high intraindividual variability. However, in comparisons of plasma levels between two groups, relatively small sample sizes seemed to give adequate statistical power to detect possible differences in FVII:Ag and plasminogen. In conclusion, the long-term repeatability of fibrinogen and FVII:C is similar to that of triglycerides and even better than that of diastolic blood pressure, but somewhat lower than the repeatability of total cholesterol. FVII:Ag and plasminogen did not have very good repeatability and more than one measurement of them should be considered if they are used as predictors of cardiovascular disease in prospective studies.

Cardiovascular Diseases↗

Effects of dietary fat modification on fibrinogen, factor VII, and plasminogen activator inhibitor-1 activity in subjects with impaired glucose tolerance.

Our aim was to assess the impact of a monounsaturated fat-enriched (Mono) diet and a diet recommended by the National Cholesterol Education Program (NCEP) on plasma levels of fibrinogen and activities of factor VII (FVII:C) and plasminogen activator inhibitor-1 (PAI-1) and the impact of genetic polymorphisms of these variables (HaeIII, MspI, and 4G/5G polymorphisms, respectively) in 28 subjects with impaired glucose tolerance ([IGT] 17 men and 11 women; mean age, 55.6 +/- 5.5 years). A diet rich in fat and saturated fatty acids served as a baseline diet for 3 weeks. Thereafter, subjects were randomized for the next 8 weeks to either the Mono diet (n = 12) or NCEP diet (n = 18). Fibrinogen levels or PAI-1 activities did not change with either of the diets, but fibrinogen levels were higher (3.4 +/- 0.5 v 4.0 +/- 0.6 g/L, P = .007 at baseline) throughout the study in heterozygous subjects with respect to HaeIII polymorphism. This polymorphism and age accounted for 38% of the variation of fibrinogen levels. MspI polymorphism together with body mass index explained 51% of the variation of FVII:C, which was higher in subjects with the M1M1 genotype compared with M1M2/M2M2 genotypes (127% +/- 21% v 90% +/- 12%, P < .001). FVII:C showed a decrease with the NCEP diet (P < .05), but the decline was confined to M1M1 subjects. PAI-1 activity did not differ significantly between the genotypes. The insulin sensitivity index (SI) obtained by the minimal model method was the main explanatory variable of PAI-1 activity. To conclude, despite good compliance, the fat-modified diet did not alter plasma levels of fibrinogen or PAI-1 in white subjects with IGT. FVII:C levels decreased with the NCEP diet, but this was confined to subjects with the M1M1 genotype.

Analysis of Variance↗

Association of the fatty acid composition of serum phospholipids with hemostatic factors.

It has been suggested that the fatty acid composition of serum phospholipids is an independent risk factor for cardiovascular disease. We examined the association of the fatty acid composition of serum phospholipids with fibrinogen, factor VII antigen (FVII:Ag), factor VII coagulant activity (FVII:C), plasminogen, and lipoprotein(a) [Lp(a)] in 338 men and 363 women 45 to 64 years old. Palmitic acid, the most abundant saturated fatty acid, was positively associated in univariate analyses with plasminogen, which explained 5.2% of its variance among men (P<.0001) and 5.8% among women (P<.0001). Linoleic acid, which is the most abundant polyunsaturated fatty acid, was negatively associated with plasminogen and fibrinogen. This explained 1.1% of the variance in fibrinogen among men (P=.04) and 3.2% among women (P=.0006) and 4.1% of the variance in plasminogen in both sexes (P<.0001). Dihomogammalinolenic acid was positively associated with FVII:Ag and explained 3.7% of its variance among men (P=.0003) and 4.6% among women (P<.0001). Furthermore, dihomogammalinolenic acid was positively and significantly associated with FVII:C, fibrinogen, and plasminogen among women but not among men. All these associations remained significant after adjustment for multiple potential confounding factors such as age, smoking, serum lipids, and body mass index. In conclusion, our findings suggest that linoleic acid, palmitic acid, and dihomogammalinoleic acid are significant independent determinants of hemostatic profile. It is not clear, however, to what extent these results reflect the effects of fatty acids on coagulation and to what extent they reflect the activity of inflammatory processes in the arteries.

8,11,14-Eicosatrienoic Acid↗

Fibrinolysis, antithrombin III, and protein C in neonates during cardiac operations.

Fibrinolysis and coagulation were studied in 10 neonates undergoing cardiac operations for congenital heart defects. Coagulation was activated during cardiopulmonary bypass as evidenced by highly increased prothrombin fragment 1 + 2 levels compared with preoperative values. Prothrombin fragment 1 + 2 levels remained elevated until postoperative day 3. Unlike coagulation, fibrinolysis was not activated during cardiopulmonary bypass but did show late activation on postoperative day 3, as evidenced by elevated levels of the fibrin degradation product D-dimer. Lack of fibrinolytic activation during bypass and its appearance on postoperative day 3 were partly explained by changes observed in tissue plasminogen activator and its inhibitor. During bypass, levels of tissue plasminogen activator and its inhibitor increased by 3.4-fold and 3.2-fold, respectively. In the postoperative period, levels of plasminogen activator inhibitor normalized rapidly whereas tissue plasminogen activator remained elevated, resulting in late fibrinolytic activation on postoperative day 3. In accordance with elevated prothrombin fragment 1 + 2, platelet count, antithrombin III, protein C, prothrombin, and factor VII were decreased on postoperative day 2, indicating ongoing consumptive coagulopathy. Nine patients had antithrombin III and six had protein C levels below age-specific normal ranges, consistent with an acquired deficiency state. Three had central venous thrombosis by postoperative day 4 or 5. In all three, thrombosis was preceded by antithrombin III deficiency, protein C deficiency, and highly elevated plasminogen activator inhibitor (3.7 to 37 times the mean of the other patients) on postoperative days 1 to 3. In conclusion, cardiopulmonary bypass in neonates caused rapid and profound alterations in the coagulation and fibrinolytic systems and initiated consumptive coagulopathy lasting until at least postoperative day 3. Thrombophilic abnormalities in antithrombin III, protein C, and fibrinolysis were frequently found and were associated with serious thrombotic complications.

Antithrombin III↗

Plasma ascorbate protects coagulation factors against photooxidation.

It has been suggested that proteins, unlike lipids, are not protected against oxidative damage by antioxidants in plasma. We have studied the effect of photodynamic virus inactivation treatment of fresh human plasma on coagulation factor activities. Photodynamic treatment generates singlet oxygen which causes inactivation of fibrinogen and factor VII. Other coagulation factors or anticoagulant proteins are clearly less affected. We found that there is an inverse correlation between the extent of coagulation factor inactivation during the treatment and the plasma ascorbate concentration. The inactivation of coagulation factors was prevented in a dose-dependent manner by adding ascorbate to the plasma before the treatment. Ascorbate was consumed during the treatment at an apparently linear rate. Oxidation of urate and coagulation factors was enhanced when ascorbate had disappeared from plasma. These results indicate that ascorbate is a primary antioxidant against photooxidation in plasma and that it effectively prevents oxidative damage to coagulation factors and other proteins.

Antioxidants↗

Fibrinogenemia Tampere--a dysfibrinogenemia with defective gelation and thromboembolic disease.

Fibrinogen Tampere was found in a woman with severe thromboembolic disease. The thrombin induced clotting time of her plasma and purified fibrinogen was slightly prolonged. The activation of fibrinogen Tampere appeared to be normal but subsequent gelation was defective. We studied fibrin gels formed at different ionic strengths and at different fibrinogen and calcium concentrations by liquid permeation, turbidity, and 3D laser microscopy. Crosslinking was studied by SDS-gel electrophoresis. The gels formed from fibrinogen Tampere were at ionic strength above 0.2 much tighter and had lower fiber mass-length ratios than normal gels as judged by permeability and turbidity data. At ionic strength 0.15 and at different calcium concentrations analysis by permeability showed the same results for fibrinogen Tampere as for normal gels. Analysis by turbidity at ionic strength 0.15 suggested swelling of the fibers at low calcium concentrations. 3D microscopy revealed perturbed clot architecture under all conditions. In fibrin gels from fibrinogen Tampere, the gamma-chain crosslinking was normal but the crosslinking of alpha-chains was delayed at ionic strength 0.2 and also at lower ionic strengths on lowering the calcium concentration. The abnormal gelation may be due to a mutation in the fibrinogen molecule. Tendency to form tight fibrin gels and/or insufficient crosslinked fibrin matrix may be pathogenetic in this thrombotic disease.

Adult↗

Cellular fibronectin in serum and plasma: a potential new tumour marker?

The concentration of cellular fibronectin (cFN) containing the extra domain A (EDA) was measured in 479 plasma and 300 serum samples from healthy blood donors by a competitive enzyme immunoassay (EIA). Serum and plasma samples contained low concentrations of EDAcFN. The mean concentration of EDAcFN was higher in plasma (2.46 mg l-1) than in serum (0.30 mg l-1). No significant differences between sexes or age groups were found. The EDAcFN concentrations were also measured in 120 patients with various malignancies. The mean values in serum were 4.28 mg l-1, 2.01 mg l-1 and 5.18 mg l-1 in patients with digestive tract malignancies, breast cancer and a group of miscellaneous cancers respectively. In plasma, the corresponding values were 12.26 mg l-1, 4.38 mg l-1 and 11.12 mg l-1 respectively. The serum EDAcFN concentration was higher than the 97.5th percentile level of healthy blood donors in 86% of patients with digestive tract and in 76% with miscellaneous malignancies. In patients with breast cancer 60% had elevated levels of EDAcFN. The corresponding figures for plasma samples in patients with digestive tract and miscellaneous malignancies were 79% and 71% respectively. In patients with breast cancer only 30% had elevated plasma levels of EDAcFN. The mean values in serum and plasma of 20 patients with benign diseases were below the cut-off levels. Consistent with the EIA results, Western blotting revealed increased amounts of EDAcFN in blood samples from cancer patients. Pregnancy did not affect the EDAcFN concentration. The mean values in 20 pregnant women were below the cut-off levels.

Antibodies, Monoclonal↗

Haemostatic and other cardiovascular risk factors, and socioeconomic status among middle-aged Finnish men and women.

BACKGROUND: The higher morbidity and mortality due to cardiovascular diseases (CVD) in lower social classes has been shown repeatedly in Finland. Lower socioeconomic groups also have a more adverse CVD risk factor profile. The association between socioeconomic factors and risk of CVD is only partly explained by the traditional risk factors. Fibrinogen may be of particular importance as an underlying mechanism that mediates this association. MATERIAL AND METHODS: The association of socioeconomic status (SES), as measured by years of education and family income with coronary risk factors was studied among a random population-based sample (N = 2365) of Finnish men and women aged 45 to 64. Subjects were studied in three parts of Finland; North Karelia, the Helsinki area, and South-West Finland, in connection with a larger cardiovascular monitoring programme. Years of education was divided into four categories (< or = 7, 8-9, 10-12, > or = 13) and family income into quartiles. The coronary risk factors studied were serum total cholesterol, HDL-cholesterol, triglycerides, blood pressure, prevalence of hypertension, smoking, body mass index (BMI), waist-to-hip ratio, prevalence of obesity, alcohol use and the following haemostatic factors: plasma fibrinogen, factor VII coagulant activity (factor VII:C), factor VII antigen (factor VII:Ag) and plasminogen. RESULTS: Adjusting for age and area of residence, both men and women of low SES tended either to have more adverse risk factor levels or there was no association. The only exception was proportion of heavy drinkers, which was higher among higher social class women. The inverse association of SES were especially strong and consistent with smoking among men, and with BMI in both sexes. Of the haemostatic factors studied, plasma fibrinogen was inversely associated with SES in both sexes. The association disappeared after adjustment for smoking among men but not among women. Among women, plasma factor VII:Ag was inversely associated with income. No other statistically significant associations of haemostatic factors with SES were observed. CONCLUSIONS: Low SES groups had more adverse levels of most of the CVD risk factors. Haemostatic factors appeared to be associated with SES especially among women.

Blood Proteins↗

Habitual diet, platelet function, fibrinogen and factor VII coagulant activity in young Finns.

OBJECTIVES: The objective of the study was to determine whether an association between diet and platelet function, plasma fibrinogen level and factor VII coagulant activity (VII:C) could be established in young subjects. DESIGN: Data on the habitual diet of the subjects were collected either by a questionnaire on food habits (n = 204) or by a 48-h dietary recall interview (n = 53). SUBJECTS: The subjects were participants in the project 'Cardiovascular Risk in Young Finns' (age range 15-30 years). A total of 204 subjects having a questionnaire on food habits participated in the platelet function tests and 53 also participated in a 48-h dietary recall interview. Plasma fibrinogen concentration and factor VII: C were measured from 79 subjects. MAIN OUTCOME MEASURES: Platelet function was tested by turbidometric measurement of platelet aggregation using ADP and collagen as aggregation agents. RESULTS: Platelet aggregation with ADP (at up to 4.0 mumol L-1) and collagen (at up to 5.0 micrograms mL-1 platelet-rich plasma PRP) showed that the diet characterized as 'saturated', i.e. containing high-fat milk and saturated fat, was associated with platelets less sensitive to aggregating agents in vitro when compared to the unsaturated type of diet. Collagen- but not ADP-induced aggregation decreased with age of the subjects (P = 0.026-0.057, regression coefficient). An inverse regression coefficient between plasma factor VII:C (101%; range 64-145%) and serum triglycerides (P = 0.006) and the intake of rye (g 1000 kcal-1; P = 0.03) were found. CONCLUSIONS: In this study we showed that platelet reactivity and factor VII:C already differ considerably between subjects at a young age, and diet may explain some of this variation.

Adolescent↗

Association of hormone replacement therapy with hemostatic and other cardiovascular risk factors. The FINRISK Hemostasis Study.

The risk of cardiovascular diseases in women is small until menopause but increases considerably afterwards. When all age groups are considered, cardiovascular diseases are responsible for approximately half of the total mortality in women. It has been suggested that hormone replacement therapy (HRT) in perimenopausal and postmenopausal women could be useful in the prevention of cardiovascular diseases, but its effects are insufficiently known. We performed a cross-sectional study on the associations of menopause and HRT with cardiovascular risk factors, in particular with hemostatic factors, on female participants of the FINRISK Hemostasis Study. The participants, aged 45 to 64 years, were recruited from the Finnish population register by random sampling from three geographically defined areas. The participation rate of women was 83.2%. Of the 1202 women included in the study, 29.2% were current users of HRT. Differences in cardiovascular risk factors by menopausal status and by HRT use were examined after adjustment for age, study area, current smoking, body mass index, self-reported diabetes, and years of education. Postmenopausal women not using exogenous sex hormones had on average a total cholesterol level 0.5 mmol/L (8.9%) higher and an LDL cholesterol level 0.4 mmol/L (11.4%) higher than premenopausal women. Women reporting irregular menstruation (presumably due to perimenopause) had higher adjusted plasma fibrinogen, factor VII coagulant activity, and factor VII antigen than women with regular menstruation or no menstrual periods.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Coagulation↗

Deficiency in the A-subunit of coagulation factor XIII: two novel point mutations demonstrate different effects on transcript levels.

Congenital deficiency in coagulation factor XIII is a rare autosomal recessive bleeding disorder. Although the defect was characterized over 30 years ago, little is known about the molecular basis of the disorder. Here, we show two novel point mutations in the gene of the A-subunit of factor XIII in the genetically isolated population of Finland. All eight factor XIII-deficient families identified in Finland were studied. The exons of the gene of A-subunit were amplified individually by polymerase chain reaction and subsequently screened by single-strand conformation polymorphism. Sequence analysis of the abnormally migrating fragments showed two point mutations resulting in an amino acid alteration. A C-to-T transition at Arg-661 in exon XIV created a premature stop codon. This mutation was detected in six of the eight families, thus being the major alteration causing FXIII deficiency in Finland. In two of the six families, the patients were compound heterozygotes with the Arg-661-Stop mutation in one allele and either a T-to-C point mutation in exon VI or a thus far uncharacterized mutation in the other allele. The T-to-C transition in exon VI resulted in a substitution of threonine for methionine 242. The transition was found in one family only, where it was in the heterozygote form combined with the Arg-661-Stop mutation. To evaluate the consequences of these mutations, steady-state FXIII mRNA levels were quantitated by solid-phase minisequencing. In addition to the termination of translation 70 amino acids before the initial stop codon, the Arg-661-Stop mutation causes a 10- to 30-fold reduction in FXIII mRNA levels. This is also likely to result in a low translation level in the truncated polypeptide. In contrast, Met-242-Thr mutation does not seem to affect the level of mRNA. Here, the absence of a functional and immunodetectable protein is probably caused by an altered conformation of the mutant polypeptide, resulting in early degradation of the defective protein.

Adolescent↗

Haemostatic factors and prevalent coronary heart disease; the FINRISK Haemostasis Study.

We examined the association of haemostatic factors with prevalent coronary heart disease (CHD) in the population-based FINRISK Haemostasis Study. Of the 2365 participants aged 45-64 years, 88 men and 44 women with prevalent CHD were identified. The participants with CHD were older and had lower high density lipoprotein cholesterol, higher triglycerides and higher body mass index than the participants without CHD. Men with CHD had significantly higher plasma fibrinogen (P < 0.0001, adjusted for age and smoking) and lipoprotein (a) (Lp (a), P = 0.001, adjusted for age) concentrations than those without CHD. Among women, the findings were consistent with those of men, but only fibrinogen reached the conventional level of statistical significance (P = 0.04). No difference was observed in factor VII antigen, factor VII activity or in plasminogen. The association of Lp (a) with prevalent CHD was dependent on fibrinogen concentration (P = 0.02 for the interaction-term) and on non-HDL cholesterol concentration (P = 0.01 for the interaction-term). These cross-sectional results do not prove causality, but they demonstrate a considerable accumulation of prevalent CHD among persons with high Lp (a), fibrinogen and non-HDL cholesterol.

Antigens↗

The effects of saturated fat and n-6 polyunsaturated fat on postprandial lipemia and hemostatic activity.

The effect of different fat loads on postprandial lipemia and hemostatic activity was examined in 10 middle-aged men using 3 different meals. One meal was rich in saturated fatty acids (cream), the other rich in n-6 polyunsaturated fatty acids (sunflower oil) and the third was fat-free containing only carbohydrates. Lipoprotein lipids and hemostatic parameters were measured during fasting and 2, 4, 6 and 8 h after the test meal. In fasting samples, several hemostatic parameters were significantly associated with lipoprotein lipids. Most notable were the strong associations of fibrinolysis parameters tissue plasminogen activator antigen and plasminogen activator inhibitor activity (PAI-1) with total and very low density lipoprotein (VLDL) triglycerides. During lipemia, the associations were approximately similar or slightly weaker than in the fasting state. Both fat loads resulted in similar postprandial lipid responses: VLDL and high density lipoprotein (HDL) triglycerides reached maximum at 4 h after the meal. VLDL cholesterol also increased 4 and 6 h after the fat loads. HDL3 cholesterol declined after the fatty meals but no change was observed in the HDL2 fraction. The fat-free meal gave no significant lipid changes during the time course studied. Factor VII activity (F VII:C) increased 6 and 8 h after the fatty meals, whereas a decrease was observed after the fat-free meal. The changes (+/- S.D.) at 8 h after cream, sunflower oil and fat-free meal were 5.2 +/- 3.3, 3.3 +/- 4.2 and -5.8 +/- 7.9 percentage points, respectively, and the effect of the meal on the changes was statistically significant (F (8,99) = 2.99, P = 0.0048). F VII antigen (F VII:Ag) tended to decline during the day but there was no difference between the meals. Factor VIII activity (F VIII:C) was highest after the polyunsaturated fat meal and lowest after the fat-free meal. PAI-1 declined during the day and the decline tended to be steepest after the fat-free morning meal. The effect of the meal on the changes in lipoprotein lipids and hemostatic factors varied significantly between individuals. In conclusion, postprandial lipemia after a single fatty meal was associated with procoagulatory change in F VII:C but there was no difference between saturated fat and n-6 polyunsaturated fat.

Adult↗

Hydroxyethyl starch as a prime for cardiopulmonary bypass: effects of two different solutions on haemostasis.

Hydroxyethyl starch (HES) is efficacious as a volume expander in cardiac surgical patients, but it may impair the haemostatic mechanisms. However, this latter effect may be less conspicuous with low molecular weight (LMW) solutions than with high molecular weight (HMW) solutions. Therefore, LMW- and HMW-HES solutions were evaluated as priming solutions for cardiopulmonary bypass (CPB) with respect to their effect on haemostasis. Forty-five patients undergoing coronary bypass grafting were prospectively randomised to three groups and received in a double-blind manner as their CPB prime either 20 ml.kg-1 LMW-HES (Mw 120,000), 20 ml.kg-1 HMW-HES (Mw 400,000) or Ringer's acetate 2000 ml. The final volume of the prime was completed to 2000 ml with Ringer's acetate in the HES groups. Anaesthesia and CPB management were standardised. Plasma levels of von Willebrand factor antigen and factor VIII procoagulant activity were significantly more depressed after CPB in both HES-groups as compared with the crystalloid prime group. In addition, APTT was more prolonged and the maximal amplitude of thromboelastographic tracing was more decreased in the HES-groups. It is concluded that it may be advisable to avoid HES solutions in the CPB prime, especially in patients with an increased risk for bleeding after cardiac operations.

Cardiopulmonary Bypass↗

Antiphospholipid antibodies and thrombosis in systemic lupus erythematosus: comparison of three lupus anticoagulant assays and anticardiolipin ELISA in 188 patients.

The presence of antiphospholipid antibodies (aPL) in 188 unselected patients with systemic lupus erythematosus was studied using the recalcification time, kaolin clotting time (KCT), dilute Russell's viper venom time (dRVVT) and anticardiolipin ELISA (aCL) to identify patients with a high or low risk of thrombosis among patients with aPL. aPL were detected by at least one method in 104 (55%) of the patients. Despite heterogeneity, lupus anticoagulant (LA) methods correlated reasonably well with each other (r = 0.736-0.968), but poorly with aCL (r = 0.241-0.549). Positivity in LA assays and immunoglobulin G (IgG)-aCL were associated with patients who experienced thrombosis (P less than 0.001 for all assays). Patients with both LA and aCL had experienced thrombosis more often than those having only one (odds = 6.3, P less than 0.001). When patients with aPL were ranked by relative strength of the finding and divided into tertiles, a history of thrombosis was associated with membership in the strongest tertile of at least one assay (odds = 4.2, P = 0.002). LA and aCL had similar sensitivities for thrombosis (61% and 63%, respectively), but LA was more specific than aCL (79% vs 53%). The best combination of two assays was KCT with dRVVT (61% sensitivity, 87% specificity). Maximal sensitivity (71%) for thrombosis could be achieved by adding IgG-aCL to these two assays, but specificity was lower (73%). In conclusion, a high thrombotic risk among patients with aPL was indicated by the simultaneous presence of both LA and aCL, strongly positive aPL, and, among aCL, IgG-class antibodies.

Adolescent↗