Snus (Swedish smokeless tobacco) use and risk of stroke: pooled analyses of incidence and survival.

BACKGROUND: Snus is a moist smokeless tobacco product with high nicotine content. Its use has a short-term effect on the cardiovascular system, but the relationship between snus use and stroke is unclear. OBJECTIVE: The aim of this study was to assess the associations between use of snus and incidence of and survival after stroke, both overall and according to subtypes. METHODS: Pooled analyses of eight Swedish prospective cohort studies were conducted, including 130 485 men who never smoked. We estimated hazard ratios (HRs) with 95% confidence intervals (CIs) of incidence and death after diagnosis using Cox proportional hazard regression models and case fatality and survival using logistic regression and Kaplan-Meier methods, respectively. RESULTS: No associations were observed between the use of snus and the risk of overall stroke (HR 1.04, 95% CI 0.92-1.17) or of any of the stroke subtypes. The odds ratio (OR) of 28-day case fatality was 1.42 (95% CI 0.99-2.04) amongst users of snus who had experienced a stroke, and the HR of death during the follow-up period was 1.32 (95% CI 1.08-1.61). CONCLUSION: Use of snus was not associated with the risk of stroke. Hence, nicotine is unlikely to contribute importantly to the pathophysiology of stroke. However, case fatality was increased in snus users, compared with nonusers, but further studies are needed to determine any possible causal mechanisms.

Dietary fibre intake and ischaemic heart disease mortality: the European Prospective Investigation into Cancer and Nutrition-Heart study.

BACKGROUND/OBJECTIVES: Evidence from prospective studies is consistent in showing an inverse association between dietary fibre intake and risk of ischaemic heart disease (IHD), but whether dietary fibre from various food sources differ in their effect on IHD risk is less clear. The objective of this study was to assess the associations of total and food sources of dietary fibre with IHD mortality in the European Prospective Investigation into Cancer and Nutrition-Heart study. SUBJECTS/METHODS: Participants were 306,331 men and women from eight European countries. Dietary fibre intake was assessed using centre or country-specific diet questionnaires and calibrated using a 24-h diet recall. RESULTS: After an average follow-up of 11.5 years, there were 2381 IHD deaths among participants without cardiovascular disease at baseline. The calibrated intake of dietary fibre was inversely related with IHD mortality; each 10 g/day was associated with a 15% lower risk (relative risk (RR) 0.85; 95% confidence interval (CI): 0.73-0.99, P=0.031). There was no difference in the associations of the individual food sources of dietary fibre with the risk of IHD mortality; RR for each 5 g/day higher cereal fibre intake was 0.91 (CI: 0.82-1.01), RR for each 2.5 g/day fruit fibre intake was 0.94 (CI: 0.88-1.01) and RR for each 2.5 g/day vegetable fibre intake was 0.90 (95% CI: 0.76-1.07). CONCLUSION: A higher consumption of dietary fibre is associated with a lower risk of fatal IHD with no clear difference in the association with IHD for fibre from cereals, fruits or vegetables.

Low-carbohydrate, high-protein score and mortality in a northern Swedish population-based cohort.

BACKGROUND/OBJECTIVE: Long-term effects of carbohydrate-restricted diets are unclear. We examined a low-carbohydrate, high-protein (LCHP) score in relation to mortality. SUBJECTS/METHODS: This is a population-based cohort study on adults in the northern Swedish county of Västerbotten. In 37,639 men (1460 deaths) and 39,680 women (923 deaths) from the population-based Västerbotten Intervention Program, deciles of energy-adjusted carbohydrate (descending) and protein (ascending) intake were added to create an LCHP score (2-20 points). Sex-specific hazard ratios (HR) were calculated by Cox regression. RESULTS: Median intakes of carbohydrates, protein and fat in subjects with LCHP scores 2-20 ranged from 61.0% to 38.6%, 11.3% to 19.2% and 26.6% to 41.5% of total energy intake, respectively. High LCHP score (14-20 points) did not predict all-cause mortality compared with low LCHP score (2-8 points), after accounting for saturated fat intake and established risk factors (men: HR for high vs low 1.03 (95% confidence interval (CI) 0.88-1.20), P for continuous = 0.721; women: HR for high vs low 1.10 (95% CI 0.91-1.32), P for continuous = 0.229). For cancer and cardiovascular disease, no clear associations were found. Carbohydrate intake was inversely associated with all-cause mortality, though only statistically significant in women (multivariate HR per decile increase 0.95 (95% CI 0.91-0.99), P = 0.010). CONCLUSION: Our results do not support a clear, general association between LCHP score and mortality. Studies encompassing a wider range of macronutrient consumption may be necessary to detect such an association.

Low bone mineral density is associated with increased risk for myocardial infarction in men and women.

UNLABELLED: The association between bone mineral density (BMD) and myocardial infarction (MI) was investigated in 6,872 men and women. For both men and women, lower BMD in the femoral neck and hip was associated with increased risk of MI largely independent of smoking, hypertension, hypertriglyceridemia, and diabetes. INTRODUCTION: The relationship between BMD and cardiovascular disease is not completely understood. The objective of this prospective study was to investigate the risk of MI in relation to bone mineral density and to determine if cardiovascular risk factors could explain this association. METHODS: Dual energy X-ray absorptiometry was performed in 5,490 women and 1,382 men to determine total hip and femoral neck BMD (in grams per square centimeters) and estimate femoral neck volumetric BMD (in grams per cubic centimeters). During a mean follow-up time of 5.7 years, 117 women and 79 men suffered an initial MI. RESULTS: After adjustment for age and BMI, lower BMD of the femoral neck and total hip was associated with increased risk of MI for both women [hazard ratio (HR) = 1.33, 95% confidence interval (CI) 1.08-1.66 per standard deviation (SD) decrease in femoral neck BMD] and men (HR = 1.74, 95% CI 1.34-2.28 per SD decrease in total hip BMD). After additional adjustment for smoking, hypertension, hypertriglyceridemia, and diabetes, the associations were slightly attenuated in men (HR = 1.42-1.88 in the age and BMI-adjusted model versus 1.33-1.77 in the fully adjusted model) while similar attenuations were seen in women (HR = 1.06-1.25 versus 1.05-1.22). CONCLUSION: Lower BMD was associated with an increase in MI risk for both men and women. Women had consistently lower HRs compared to men in all models. Adjusting for smoking, hypertension, hypertriglyceridemia, and diabetes did not distinctively weaken these associations.

Von Willebrand factor predicts major bleeding and mortality during oral anticoagulant treatment.

AIMS: Oral anticoagulation (OAC), predominantly with warfarin, is an effective treatment to prevent thromboembolic events. Serious bleeding is a frequent and feared treatment complication. In this longitudinal cohort study of OAC-treated patients, we aimed to evaluate the relationship between von Willebrand factor (VWF) levels and risk of bleeding complications, cardiovascular mortality and all-cause mortality. METHODS AND RESULTS: A total of 719 patients receiving warfarin treatment were observed for a mean duration of 4.2 years. All bleeding complications causing hospitalization were registered and classified into clinically relevant bleeding (CRB) and major bleeding. Ischaemic stroke, peripheral arterial embolism, myocardial infarction, and death were also recorded. We identified 113 cases of CRB and 73 of major bleeding. In total, 161 deaths occurred during follow-up with cardiovascular disease identified as the cause of death in 110 patients. Patients in the highest tertile of VWF had a significantly increased risk of bleeding complications: hazard ratio (HR) 2.53 (95% CI 1.41-4.56) for major bleeding and HR 2.19 (95% CI 1.38-3.48) for CRB. VWF, expressed either in tertiles or as a continuous variable, showed a significant association with cardiovascular mortality (HR 1.68, 95% CI 1.40-2.01) and all-cause mortality (HR 1.77, 95% CI 1.52-2.05). In multivariate Cox regression analysis, the findings remained significant after adjusting for age, high-sensitivity C-reactive protein and creatinine. CONCLUSIONS: Patients with high levels of VWF had an increased risk of bleeding complications, cardiovascular mortality and all-cause mortality during OAC treatment. Our findings imply that the use of VWF as a risk marker for thromboembolic events is complicated by the association of VWF with bleeding complications.

The disparity between long-term survival in patients with and without diabetes following a first myocardial infarction did not change between 1989 and 2006: an analysis of 6,776 patients in the Northern Sweden MONICA Study.

AIMS/HYPOTHESIS: Long-term survival after myocardial infarction (MI) has improved in the population, but data on diabetic patients is lacking. We analysed survival for up to 18 years after a first MI in patients with or without diabetes. METHODS: The Northern Sweden MONICA Myocardial Infarction Registry was linked to the Cause-of-Death Registry for a total of 6,776 patients, 25-64 years of age, with a first MI during 1989-2006. Prehospital deaths were included. Follow-up ended on 30 August 2008. RESULTS: Sixteen per cent had diabetes. Median follow-up time was 6.8 years, and the study included 50,667 patient-years. One third of the non-diabetic patients died vs half of the diabetic patients. Median survival for non-diabetic men was 227 months and for diabetic men 123 months. Corresponding figures for the non-diabetic and diabetic women were 222 and 81 months respectively. Men with diabetes had an age-adjusted HR for all-cause mortality of 1.56 (95% CI 1.39, 1.79) vs men without diabetes. Mortality risk was higher among diabetic women, HR 1.97 (1.62, 2.39) (diabetes × sex interaction, p = 0.03). Survival increased for three consecutive cohorts and was higher in non-diabetic patients for all durations of follow-up and in all three cohorts. The interaction of diabetes x cohort was not significant over time (p = 0.5) and HRs did not differ either. CONCLUSIONS/INTERPRETATION: Long-term survival after a first MI is markedly lower in diabetic patients, especially among women, over an 18-year observation time. Although survival has improved in diabetic patients, the effect of diabetes upon mortality has not diminished.

Large improvements in major cardiovascular risk factors in the population of northern Sweden: the MONICA study 1986-2009.

OBJECTIVES: the incidence of cardiovascular disease has declined rapidly in Sweden since the 1980s. We explored changes in major cardiovascular risk factors in northern Sweden between 1986 and 2009. DESIGN: since 1986, six population surveys have been carried out in northern Sweden using procedures of the World Health Organization MONICA project. The population age range was 25-64 years in 1986 and 1990, and 25-74 years from 1994. Trends were analysed using generalized linear models. RESULTS: a total of 10586 subjects were included in the surveys. Blood pressure decreased by 4.9/3.9 mmHg in women and 1.8/1.5 mmHg in men aged 25-64 years between 1986 and 2009. In men and women aged 65-74 years, the decrease was 12.6/6.1 mmHg between 1994 and 2009. From 1994, the use of blood pressure-lowering drugs increased, particularly among the older subgroup. The prevalence of smoking halved between 1986 and 2009; 11% of women and 9% of men were smokers in 2009. Cholesterol levels decreased by 0.9 mmol L(-1) in the younger age group (25-64 years), and the use of lipid-lowering agents increased from 1994. Among subjects aged 25-64 years, one in five was obese in 2009, which was twice as many as in 1986, and body mass index (BMI) increased by 1.5 kg m(-2) , corresponding to an increase in weight of 4 kg. There was no further increase in BMI from 2004. The prevalence of diabetes did not change between 1986 and 2009. The proportion that received a university education increased markedly in all age groups, especially in women, during the study period. CONCLUSIONS: significant improvements were observed in major cardiovascular risk factors in northern Sweden between 1986 and 2009.

Abdominal and gynoid adipose distribution and incident myocardial infarction in women and men.

OBJECTIVE: The relationships between objectively measured abdominal and gynoid adipose mass with the prospective risk of myocardial infarction (MI) has been scarcely investigated. We aimed to investigate the associations between fat distribution and the risk of MI. SUBJECTS: Total and regional fat mass was measured using dual-energy X-ray absorptiometry (DEXA) in 2336 women and 922 men, of whom 104 subsequently experienced an MI during a mean follow-up time of 7.8 years. RESULTS: In women, the strongest independent predictor of MI was the ratio of abdominal to gynoid adipose mass (hazard ratio (HR)=2.44, 95% confidence interval (CI) 1.79-3.32 per s.d. increase in adipose mass), after adjustment for age and smoking. This ratio also showed a strong association with hypertension, impaired glucose tolerance and hypertriglyceridemia (P<0.01 for all). In contrast, the ratio of gynoid to total adipose mass was associated with a reduced risk of MI (HR= 0.57, 95% CI 0.43-0.77), and reduced risk of hypertension, impaired glucose tolerance and hypertriglyceridemia (P<0.001 for all). In men, gynoid fat mass was associated with a decreased risk of MI (HR=0.69, 95% CI 0.48-0.98), and abdominal fat mass was associated with hypertriglyceridemia (P for trend 0.02). CONCLUSION: In summary, fat distribution was a strong predictor of the risk of MI in women, but not in men. These different results may be explained by the associations found between fat distribution and hypertension, impaired glucose tolerance and hypertriglyceridemia.

Consumption of filtered and boiled coffee and the risk of first acute myocardial infarction; a nested case/referent study.

BACKGROUND AND AIM: In northern Sweden, consumption of both filtered and boiled coffee is common. Boiled coffee, especially popular in rural areas, is known to raise blood lipids, a risk factor for acute myocardial infarction (MI). To our knowledge, only one epidemiological study, a case-control study from Sweden, has investigated boiled coffee in MI, noting an increased risk at high consumption levels in men, and no association in women. The aim of the present nested case-referent study was to relate consumption of filtered and boiled coffee to the risk of first MI. METHODS AND RESULTS: The study subjects were 375 cases (303 men, 72 women) and 1293 matched referents from the population-based Northern Sweden Health and Disease Study. Coffee consumption was assessed by food frequency questionnaire. Risk estimates were calculated by conditional logistic regression. A statistically significant positive association was found between consumption of filtered coffee and MI risk in men [odds ratio for consumption > or = 4 times/day versus < or = 1 time/day 1.73 (95% CI 1.05-2.84)]. In women, a similar association was observed, but for boiled coffee [odds ratio 2.51 (95% CI 1.08-5.86)]. After adjustment for current smoking, postsecondary education, hypertension, and sedentary lifestyle, the results for women were no longer statistically significant. CONCLUSION: Consumption of filtered coffee was positively associated with the risk of a first MI in men. A similar tendency was observed for boiled coffee in women, but the result was not statistically significant in multivariate analysis. Further investigation in a larger study is warranted.

Plasma folate and total homocysteine levels are associated with the risk of myocardial infarction, independently of each other and of renal function.

OBJECTIVES: To investigate the relationship between plasma folate, vitamin B12 and total homocysteine concentrations, dietary intake of folate and vitamins B12, B6 and B2, and the risk of first acute myocardial infarction (MI). DESIGN: Nested case-referent study with up to 13 years of follow-up. SETTING: The population-based Northern Sweden Health and Disease Study, with 73 879 participants at the time of case ascertainment. SUBJECTS: A total of 571 MI cases (406 men) and 1569 matched referents. Of the cases, 530 had plasma samples available, and 247 had dietary B-vitamin intake data. RESULTS: Plasma concentrations of folate were inversely associated, and total homocysteine positively associated, with the risk of MI, independently of each other and of a number of established and novel cardiovascular risk factors, including renal function [multivariate odds ratio for highest vs. lowest quintile of folate 0.52 (95% CI 0.31-0.84), P for trend = 0.036, and homocysteine 1.92 (95% CI 1.20-3.09), P for trend = 0.006]. For plasma vitamin B12 concentrations, and vitamin B12, B6 and B2 intake, no clear risk relationship was apparent. Though not statistically significant, the results for folate intake were consistent with those for plasma concentrations. CONCLUSIONS: In this large prospective study of a population without mandatory folic acid fortification, both folate and homocysteine were strongly associated with the risk of myocardial infarction, independently of each other and of renal function. Although randomized trials of folic acid supplementation are needed to determine causality, our findings highlight the potential importance of folate, or sources of folate, in incident cardiovascular disease.

Efficacy and safety of anticoagulant prophylaxis to prevent venous thromboembolism in acutely ill medical inpatients: a meta-analysis.

OBJECTIVES: Venous thromboembolism (VTE) is a potentially serious complication of hospitalization and immobilization. The use of anticoagulant prophylaxis in acutely ill medical inpatients is still under debate. New data including a recent meta-analysis have recently been published. We aim at studying the efficacy and safety of anticoagulant prophylaxis in acutely ill medical inpatients, and demonstrate differences between meta-analyses due to different data extraction from the heterogeneous studies included. SUBJECTS: The Cochrane Library, MEDLINE and EMBASE were searched from 1980 to present. Manual searches were performed regarding abstracts from major meetings. Seven blinded randomized controlled clinical trials assessing the prophylactic effect of heparin in acutely ill medical patients were identified and included in the meta-analysis. RESULTS: Low-molecular weight heparin (LMWH) prophylaxis prevented 48% of symptomatic pulmonary embolism (PE), 48% of symptomatic deep vein thrombosis (DVT) (not significant) and 51% of asymptomatic DVT. A nonsignificant trend towards higher bleeding risk during LMWH prophylaxis was found. Death was not significantly affected. We compared our data with a recent meta-analysis with different study selection and data extraction and found similar results. CONCLUSIONS: As DVT and PE are manifestations of the same illness, VTE, one can argue that anticoagulant prophylaxis prevents approximately half of the expected events. Most medical inpatients have short hospital stays, and a low risk of VTE. The important task for the clinician is to identify patients with a sufficiently high risk of symptomatic VTE to warrant LMWH prophylaxis. Despite differences in study selection and data extraction, our study shows results similar to a recent meta-analysis.

Modified Mediterranean diet and survival after myocardial infarction: the EPIC-Elderly study.

Mediterranean diet is associated with lower incidence of coronary heart disease, and two randomised trials indicated that it improves prognosis of coronary patients. These trials, however, relied on a total of 100 deaths and evaluated designer diets in the clinical context. We have evaluated the association of adherence to the modified Mediterranean diet, in which unsaturates were substituted for monounsaturates, with survival among elderly with previous myocardial infarction within the European Prospective Investigation into Cancer and nutrition (EPIC) study. As of December 2003, after a median follow-up of 6.7 years, 2671 EPIC participants from nine countries were 60 years or older and had prevalent myocardial infarction but no stroke or cancer at enrolment, complete information on dietary intakes and important covariates and known survival status. Adherence to the modified Mediterranean diet was assessed through a 10-unit-scale. Mortality ratio in relation to modified Mediterranean diet was estimated through Cox regression controlling for possible confounding. Increased adherence to modified Mediterranean diet by two units was associated with 18% lower overall mortality rate (95% confidence interval 7-27%, fixed effects model). There was no significant heterogeneity by sex, age at enrolment, or country, although the association tended to be less evident among northern Europeans. Associations between food groups contributing to the modified Mediterranean diet and mortality were generally weak. A diet inspired by the Mediterranean pattern that can be easily adopted by Western populations is associated with substantial reduction of total mortality of coronary patients in the community.

The risk of myocardial infarction and sudden cardiac death amongst snuff users with or without a previous history of smoking.

OBJECTIVES: To investigate the risk of a first myocardial infarction (MI) and sudden cardiac death (SCD) amongst male snuff users. DESIGN: We used a prospective incident case-referent study design nested in the population-based Västerbotten Intervention Program and the Northern Sweden MONICA study. SUBJECTS: Tobacco habits and cardiovascular risk factors were assessed at baseline screening and compared in 525 male MI cases (including 93 SCD cases) and 1798 matched referents. RESULTS: Myocardial infarction occurred on average 4 years and 2 months after the baseline screening. No increased risk for MI was found amongst snuff users without a previous history of smoking compared with nontobacco users after adjustments for body mass index, leisure time physical activity, educational level and cholesterol level (OR 0.82; 95% CI, 0.46-1.43). For snuff users with a previous history of smoking, the adjusted OR was 1.25 (95% CI, 0.80-1.96). Significantly increased risk for MI was found in current smokers with or without current snuff use. For SCD cases with survival time<24 h, the adjusted OR for snuff users without previous history of smoking was 1.18 (95% CI, 0.38-3.70) and for cases with survival time<1 h the OR was 0.38 (95% CI, 0.08-1.89). CONCLUSIONS: We found no increased risk for MI amongst snuff users without a previous history of smoking. Amongst snuff users with a previous history of smoking, the tendency towards an increased risk for MI may reflect the residual risk from former smoking. This study does not support the hypothesis that the risk for SCD is increased amongst snuff users.

Time trends in population cholesterol levels 1986-2004: influence of lipid-lowering drugs, obesity, smoking and educational level. The northern Sweden MONICA study.

OBJECTIVES: To explore time trends in population total cholesterol. DESIGN AND SETTING: Five population-based cross-sectional surveys, 1986-2004 in the northern Sweden MONICA study included 8827 men and women. RESULTS: Age-adjusted cholesterol level declined in men, 25-64 years old, from 6.38 to 5.78 mmol L(-1) and in women from 6.32 to 5.51 mmol L(-1). Between 1994 and 2004, subjects 65-74 years old were included, and their levels also decreased, in men from 6.35 to 5.76 mmol L(-1) and in women from 7.11 to 6.24 mmol L(-1). The decrease was continuous over surveys and age groups, except in young and middle-aged men where no further decline was found after 1999. Cohorts born 1920-1939 showed decreased cholesterol over the period, whilst no change was noted for those born thereafter. In 2004, one-fourth of men and one-third of women 25-74 years achieved levels below 5.0 mmol L(-1). Subjects with low educational level, body mass index > or =25 or smokers all had higher cholesterol levels which persisted during the 18-year period. In 2004, the 9% who used lipid-lowering drugs are estimated to contribute, at most, to 0.13 mmol L(-1) lower cholesterol in the population. CONCLUSION: Large decreases in cholesterol levels occurred in the 18-year period. Less smoking may contribute to, and increasing obesity attenuate, this trend whilst lipid-lowering drugs have had little effect until recently. Socio-economic inequalities persist.

Cognitive-behavioural stress management does not improve biological cardiovascular risk indicators in women with ischaemic heart disease: a randomized-controlled trial.

OBJECTIVES: Psychosocial factors, such as stress and vital exhaustion, are associated with an increased risk of cardiovascular events, and women report more psychosocial ill-being after an acute myocardial infarction than men. We have earlier shown that a cognitive-behavioural intervention in women with ischaemic heart disease (IHD) improved psychosocial well-being. In the present study, we tested the hypothesis that the improvement in psychosocial well-being is associated with an improvement in biochemical indicators of cardiovascular risk. DESIGN: Randomized-controlled trial in northern Sweden. SETTING: Outpatient care. SUBJECTS: Women with IHD were randomized to either a 1-year cognitive-behavioural stress management programme or usual care. Of the 159 women who completed the study, 77 were in the intervention group, and 82 in the control group. INTERVENTIONS: A 1-year cognitive-behavioural stress management programme versus conventional care. RESULTS: Group assignment was not found to be a determinant of waist circumference, high sensitive C-reactive protein (hs-CRP), fibrinogen, von Willebrand factor (vWF), plasminogen activator inhibitor type 1 (PAI-1) activity, tissue plasminogen activator (tPA) activity, tPA antigen, tPA-PAI-1 complex, leptin, or HOMA2 insulin resistance index (HOMA2-IR) at follow up. Changes in psychosocial variables were not associated with changes in any of the biological risk indicators. CONCLUSIONS: Even if our cognitive-behavioural stress management programme had effects on proximal targets, such as stress behaviour and vital exhaustion, we found no improvement in intermediate biochemical targets related to the metabolic syndrome and IHD. Our results challenge the proposition that the relationship between psychological well-being and biological cardiovascular risk indicators is a direct cause-effect phenomenon.

Influence of prolonged dalteparin treatment on coagulation, fibrinolysis and inflammation in unstable coronary artery disease.

BACKGROUND: Unstable coronary artery disease (CAD) is a multi-factorial disease involving thrombotic and inflammatory processes. Short-term low molecular weight (LMW) heparin treatment reduces coagulation activity and clinical events. We investigated the influence of prolonged treatment on coagulation, fibrinolysis and inflammation. METHODS AND RESULTS: Serial blood samples were obtained from 555 of 2,267 unstable CAD patients in the FRISC II study. Patients were treated with the LMW heparin dalteparin 120 IU kg(-1) s.c. twice daily for 5-7 days and randomized to placebo (n=285) or gender and weight-adjusted doses of dalteparin (5,000 or 7,500 IU) twice daily (n=270) for 3 months. Dalteparin persistently depressed coagulation activity with, when compared with placebo, lower median levels of factor VIIa (63 IU mL(-1) vs. 84 IU mL(-1)), prothrombin fragment 1 + 2 (0.86 nmol L(-1) vs. 1.09 nmol L(-1)) and D-dimer (21 microg L(-1) vs. 43 microug L(-1)) after 3 months, all P<0.01. Reactivation of coagulation activity was observed after cessation of both short-term and prolonged dalteparin treatment. Higher levels of tPA/PAI-1 complex (11.7 microg L(-1) vs. 6.5 microg L(-1), P<0.001) and von Willebrand factor (162% vs. 136%, P<0.001) were found during prolonged dalteparin treatment. Interleukin-6, C-reactive protein and fibrinogen levels were unaffected by dalteparin treatment. CONCLUSIONS: Three months dalteparin treatment resulted in a sustained and pronounced reduction of coagulation activity, which corresponds to the observed reduction in death and myocardial infarction during the initial 6 weeks in the FRISC II study. The persistently elevated levels of tPA/PAI-1 complex and von Willebrand factor might reflect effects on platelets and endothelial cells and thus contribute to the gradually decreased efficacy by prolonged dalteparin treatment in unstable CAD.

Elevated plasma homocysteine: cause or consequence of myocardial infarction?

OBJECTIVES: To determine whether a first myocardial infarction leads to increased plasma homocysteine concentrations and whether the association between homocysteine and myocardial infarction was greater at follow-up compared with baseline. DESIGN: A population-based, prospective, nested case-referent study. SETTING: Screening took place at the nearest health survey centre in northern Sweden. SUBJECTS: Of more than 36,000 persons screened, 78 developed a first myocardial infarction (average 18 months after sampling). Fifty of these had participated in a follow-up health survey (average 8(1/2) years between surveys) and were sex- and age-matched with 56 referents. MAIN OUTCOME MEASURES: Comparison of plasma homocysteine levels in case and referent subjects before and after development of a first myocardial infarction. RESULTS: No statistically significant difference was found between cases and referents regarding homocysteine at baseline or follow-up. Plasma homocysteine and plasma creatinine increased significantly, and plasma albumin decreased significantly over time. Conditional univariate logistic regression indicated that high homocysteine at follow-up but not baseline was associated with first myocardial infarction (OR 2.49; 95% CI: 1.03-6.02), but the relation disappeared in multivariate analyses including plasma creatinine and plasma albumin. High plasma creatinine remained associated with first myocardial infarction at both baseline (OR 2.94; 95% CI: 1.05-8.21) and follow-up (OR 3.38; 95% CI: 1.21-9.48). CONCLUSION: In this study, first myocardial infarction did not cause increased plasma homocysteine concentration.

The effect of streptokinase neutralizing antibodies on fibrinolytic activity and reperfusion following streptokinase treatment in acute myocardial infarction.

OBJECTIVES: To evaluate tissue plasminogen activator (tPA) activity as a measure of fibrinolytic response to treatment with streptokinase (SK) and to relate this to the effect of pretreatment SK antibodies and to successful reperfusion assessed by continuous computerized vectorcardiography (VCG). SETTING: Umeå University Hospital. SUBJECTS: A total of 104 patients with acute myocardial infarction (AMI) treated with SK and no history of previous SK treatment were studied. The tPA activity was measured 4 h after the start of treatment. The effect of pre-existing neutralizing antibodies to SK was analysed with a functional assay in pretreatment samples. Reperfusion was evaluated with VCG. MAIN OUTCOME MEASURES: Successful reperfusion. RESULTS: Fifty-five patients (53%) were classified as successfully reperfused. The risk for failed reperfusion was calculated in logistic regression models. In a univariate model, a borderline significant increase in the risk of failed reperfusion was observed in intermediate levels of SK neutralizing antibodies, but not in the highest levels. In a multivariate model, only high tPA activity, >25 U mL(-1), at 4 h (OR 0.17: 95% CI: 0.06-0.51) was associated with a higher rate of reperfusion whilst longer time to treatment (OR 1.17; 95% CI: 1.02-1.35) was associated with a higher risk of failed reperfusion. There was no significant correlation between neutralizing antibodies to SK and tPA activity at 4 h. CONCLUSION: The SK treatment of AMI induced high levels of tPA activity which were associated with successful reperfusion. The effect of pre-existing SK antibodies had no significant influence on reperfusion and were not correlated to the fibrinolytic activity obtained.

Markers of high fish intake are associated with decreased risk of a first myocardial infarction.

High intake of fish has been associated with reduced risk of CHD. The high content of n-3 polyunsaturated fatty acids (PUFA) in fish has been suggested to be a protective factor. In addition, fish is the entirely dominating source of methylmercury for the general population, and the concentration of Hg in erythrocytes (Ery-Hg) is often used as an index of fish consumption. Our aim was to study the relationships between a first-ever myocardial infarction, Ery-Hg, activity of gluthathione peroxidase in erythrocytes (Ery-GSH-Px) and plasma concentration of the n-3 PUFA eicosapentaenoic and docosahexaenoic acids (P-PUFA). In a population-based prospective nested case-control study within Northern Sweden seventy-eight cases of a first-ever myocardial infarction were compared with 156 controls with respect to Ery-Hg, P-PUFA and Ery-GSH-Px. Both Ery-Hg and P-PUFA, but not Ery-GSH-Px, were significantly higher in subjects reporting high fish intake (at least one meal per week) than in those with lower intake. This finding suggests that Ery-Hg and P-PUFA reflect previous long-term fish intake. Low risk of myocardial infarction was associated with high Ery-Hg or high P-PUFA. In a multivariate model the risk of myocardial infarction was further reduced in subjects with both high Ery-Hg and high P-PUFA (odds ratio 0.16, 95 % CI 0.04, 0.65). In conclusion, there is a strong inverse association between the risk of a first myocardial infarction and the biomarkers of fish intake, Ery-Hg and P-PUFA, and this association is independent of traditional risk factors.

Homozygosity for the C677-->T mutation of 5,10-methylenetetrahydrofolate reductase and total plasma homocyst(e) ine are not associated with greater than normal risk of a first myocardial infarction in northern Sweden.

BACKGROUND: Results of several case-control studies have shown elevated total plasma homocyst(e)ine (TPH) and homozygosity for the point mutation C677-->T in the gene for 5,10-methylenetetrahydrofolate reductase (MTHFR) to be associated with a greater than normal risk of atherosclerotic vascular disease. However, there have been few epidemiologic studies and the interpretation of the results is not clear-cut. OBJECTIVE: To elucidate whether homozygosity for the point mutation C677-->T in the gene for MTHFR, and TPH are risk factors for a first myocardial infarction. DESIGN: A prospective nested case-control study in Northern Sweden. METHODS: Among more than 36000 persons screened, 78 cases satisfied the inclusion criterion of having developed, after sampling, a first myocardial infarction. For each case, two controls matched for sex and age were randomly selected. RESULTS: We found no statistically significant difference among the prevalences of the three possible MTHFR genotypes -/- (no mutation), +/+ (both alleles have the mutation), and +/- among cases and controls in univariate conditional logistic regression analysis. Mean levels of TPH in patients and controls were 12.2+/-4.9 and 12.2+/-3.5 micromol/l (means +/- SD), respectively (NS). CONCLUSIONS: In this study neither homozygosity for the point mutation C677-->T in the gene for MTHFR nor TPH was related to a greater than normal risk of a first myocardial infarction for members of the population of northern Sweden. Further research is needed in order to show whether TPH is an independent risk factor for a first myocardial infarction.