Haemostatic parameters and vascular risk

Systemic inflammation, heart rate variability and air pollution in a cohort of senior adults

OBJECTIVES

Short-term elevation of ambient particulate air pollution has been associated with autonomic dysfunction and increased systemic inflammation, but the interconnections between these pathways are not well understood. We examined the association between inflammation and autonomic dysfunction and effect modification of inflammation on the association between air pollution and heart rate variability (HRV) in elderly subjects.

METHODS

25 elderly subjects in Steubenville, Ohio, were followed up to 24 times with repeated 30-min ECG Holter monitoring (545 observations). C-reactive protein (CRP), fibrinogen, interleukin-6 (IL-6), soluble inter-cellular adhesion molecule 1 (sICAM-1), and white blood cell and platelet counts were measured in peripheral blood samples collected in the first month of the study. Increased systemic inflammation was defined for subjects within the upper 20% of the distribution for each marker. A central ambient monitoring station provided daily fine particle (PM(2.5)) and sulphate (SO(4)(2-)) data. Linear mixed models were used to identify associations between inflammatory markers and HRV and to assess effect modification of the association between air pollution and HRV due to inflammatory status.

RESULTS

A 5.8 mg/l elevation in CRP was associated with decreases of between -8% and -33% for time and frequency domain HRV outcomes. A 5.1 microg/m(3) increase in SO(4)(2-) on the day before the health assessment was associated with a decrease of -6.7% in the SD of normal RR intervals (SDNN) (95% CI -11.8% to -1.3%) in subjects with elevated CRP, but not in subjects with lower CRP (p value interaction=0.04), with similar findings for PM(2.5).

CONCLUSIONS

Increased systemic inflammation is associated with autonomic dysfunction in the elderly. Air pollution effects on reduced SDNN are stronger in subjects with elevated systemic inflammation.

Linkage study of fibrinogen levels: the Strong Heart Family Study

Background

The pathogenesis of atherosclerosis involves both hemostatic and inflammatory mechanisms. Fibrinogen is associated with both risk of thrombosis and inflammation. A recent meta-analysis showed that risk of coronary heart disease may increase 1.8 fold for 1 g/L of increased fibrinogen, independent of traditional risk factors. It is known that fibrinogen levels may be influenced by demographic, environmental and genetic factors. Epidemiologic and candidate gene studies are available; but few genome-wide linkage studies have been conducted, particularly in minority populations. The Strong Heart Study has demonstrated an increased incidence of cardiovascular disease in the American Indian population, and therefore represents an important source for genetic-epidemiological investigations.

Methods

The Strong Heart Family Study enrolled over 3,600 American Indian participants in large, multi-generational families, ascertained from an ongoing population-based study in the same communities. Fibrinogen was determined using standard technique in a central laboratory and extensive additional phenotypic measures were obtained. Participants were genotyped for 382 short tandem repeat markers distributed throughout the genome; and results were analyzed using a variance decomposition method, as implemented in the SOLAR 2.0 program.

Results

Data from 3535 participants were included and after step-wise, linear regression analysis, two models were selected for investigation. Basic demographic adjustments constituted model 1, while model 2 considered waist circumference, diabetes mellitus and postmenopausal status as additional covariates. Five LOD scores between 1.82 and 3.02 were identified, with the maximally adjusted model showing the highest score on chromosome 7 at 28 cM. Genes for two key components of the inflammatory response, i.e. interleukin-6 and "signal transducer and activator of transcription 3" (STAT3), were identified within 2 and 8 Mb of this 1 LOD drop interval respectively. A LOD score of 1.82 on chromosome 17 between 68 and 93 cM is supported by reports from two other populations with LOD scores of 1.4 and 1.95.

Conclusion

In a minority population with a high prevalence of cardiovascular disease, strong evidence for a novel genetic determinant of fibrinogen levels is found on chromosome 7 at 28 cM. Four other loci, some of which have been suggested by previous studies, were also identified.

The relationship between cardiometabolic and hemostatic variables: influence of race

Elevated concentrations of hemostatic variables such as fibrinogen, plasma activator inhibitor 1 (PAI-1), and tissue plasminogen activator (t-PA)/PAI-1 complex have been implicated in the pathogenesis of arterial lesion progression and subsequent cardiovascular disease. In the present study, traditional cardiometabolic variables (CMV) associated with cardiovascular disease risk were examined in relation to hemostatic variables in a group of 36 White American (WA) and 30 African American (AA) overweight/obese women. There were 9 CMV significantly related to PAI-1 and/or the t-PA/PAI-1 ratio, but not fibrinogen. A significant race effect was found for 5 CMV in relation to fibrinogen and/or the t-PA/PAI-1 ratio, but not PAI-1. Significant race and high-density lipoprotein cholesterol interactions were found for fibrinogen (P = .021); and significant race and waist to hip ratio (P = .015), diastolic blood pressure (P = .013), and insulin (P = .037) interactions were found for PAI-1. No interactions were found for the t-PA/PAI-complex. Both PAI-1 and the t-PA/PAI-1 ratio are favored above fibrinogen in the diagnostic evaluation of health risk in both WA and AA women. Because of differences by race, independent consideration should be given in the clinical management of WA and AA women presenting with elevated CMV. Our findings indicated the t-PA/PAI-1 complex to be the most global indicator of health risk in both WA and AA overweight/obese women.

Invasive treatment performed for acute myocardial infarction in a patient with immune thrombocytopenic purpura

Acute myocardial infarction (AMI) is infrequent in patients with idiopathic thrombocytopenic purpura (ITP) so the best treatment is not well known. The next case shows a 37-year-old man with chronic ITP who suffered an anterior AMI, the platelet count at admission was 39,000 microL. He was treated successfully with primary percutaneous angioplasty under anticoagulation with unfractionated heparin and antiaggregation with clopidogrel and ASA. At the end of the procedure we sealed the femoral access site with Angio-Seal(R). He didn t have any complications during the procedure and after six months remained asymptomatic. In some patients with chronic ITP and AMI the percutaneous treatment could be a good option.

Primary percutaneous coronary intervention for acute myocardial infarction with idiopathic thrombocytopenic purpura: a case report

Acute myocardial infarction (AMI) is rare in patients with idiopathic thrombocytopenic purpura (ITP). We describe a case of an AMI during thrombocytopenia in a patient with chronic ITP. A 47-yr-old woman presented with anterior chest pain and a low platelet count (21,000/microliter) at admission. Urgent coronary angiography revealed total occlusion of proximal right coronary artery and primary percutaneous coronary intervention (PCI) was performed successfully. This case suggests that primary PCI may be a therapeutic option for an AMI in patients with ITP, even though the patient had severe thrombocytopenia.

Haemostatic and inflammatory biomarkers in advanced chronic heart failure: role of oral anticoagulants and successful heart transplantation

Advanced chronic heart failure (CHF) is associated with abnormal haemostasis and inflammation, but it is not known how these abnormalities are related, whether they are modified by oral anticoagulants (OAT), or if they persist after successful heart transplantation. We studied 25 patients with CHF (New York Heart Association class IV, 10 of whom underwent heart transplantation) and 25 age- and sex-matched healthy controls by measuring their plasma levels of prothrombin fragment 1 + 2 (F1 + 2), thrombin-antithrombin (TAT) complexes, tissue plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1), D-dimer, factor VII (FVII), fibrinogen, von Willebrand factor (VWF), tumour necrosis factor (TNF), soluble TNF receptor II (sTNFRII), interleukin 6 (IL-6), soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), endothelial-selectin (E-selectin) and thrombomodulin. CHF patients had higher plasma levels of TAT, D-dimer, t-PA, fibrinogen, VWF, TNF, IL-6, sTNFRII, sVCAM-1 (P = 0.0001), sICAM-1 (P = 0.003) and thrombomodulin (P = 0.007) than controls. There were significant correlations (r = 0.414-0.595) between coagulation, fibrinolysis, endothelial dysfunction and inflammation parameters, which were lower in those patients treated with OATs. Heart transplantation led to reductions in fibrinogen (P = 0.001), VWF (P = 0.05), D-dimer (P = 0.05) and IL-6 levels (P = 0.05), but all the parameters remained significantly higher (P = 0.01-0.0001) than in the controls. Advanced CHF is associated with coagulation activation, endothelial dysfunction and increased proinflammatory cytokine levels. Most of these abnormalities parallel each other, tend to normalize in patients treated with OATs and, although reduced, persist in patients undergoing successful heart transplantation, despite the absence of clinical signs of CHF.

Plaque composition in plexogenic and thromboembolic pulmonary hypertension: the critical role of thrombotic material in pultaceous core formation

BACKGROUND

Patients with pulmonary hypertension develop intimal plaques in large pulmonary arteries.

OBJECTIVE

To test the hypothesis that the composition of such plaques differs depending on whether the aetiology of the disease is thromboembolic or hypertensive.

DESIGN

Chronic thromboembolic and plexogenic pulmonary hypertension (primary and secondary (Eisenmenger syndrome)) were investigated. These are spontaneous human models and were used to examine the independent role of thrombus and hypertension in plaque composition.

SETTING

A national tertiary referral centre for lung transplantation and pulmonary thromboendoarterectomy.

PATIENTS

Thirty nine patients with chronic thromboembolic pulmonary hypertension who had undergone thromboendoarterectomy (n = 32) or lung transplantation (n = 7), 28 with plexogenic diseases (nine primary and 19 Eisenmenger), and three with Eisenmenger syndrome complicated by thromboembolic events.

INTERVENTIONS

The lung and thromboendoarterectomy samples were sectioned, stained with Movat pentachrome, and immunostained with antibodies for fibrin, platelets, inflammatory cells, smooth muscle cells, and erythrocyte membrane glycophorin A.

MAIN OUTCOME MEASURE

Composition of the plaques affecting large pulmonary arteries.

RESULTS

Two types of intimal lesion were distinguished in chronic thromboembolic pulmonary hypertension: fibrous plaques with angioneogenesis; and core-rich atherosclerotic plaques with pultaceous cores largely consisting of glycophorin immunoreactive material, with cholesterol clefts (61.5%), CD68 positive macrophages (84.6%), T lymphocytes (87%), and calcification (46.1%). The samples from the patients with Eisenmenger syndrome and thromboembolic complications had similar characteristics, whereas those from patients with uncomplicated primary pulmonary hypertension had core-free fibrous plaques, spotted with macrophages and T lymphocytes.

CONCLUSIONS

Chronic thromboembolic pulmonary hypertension is associated with atherosclerotic plaques with glycophorin-rich pultaceous cores, and plexogenic pulmonary hypertension with fibrous plaques. Thromboembolic material thus plays a critical role in the formation of pultaceous cores, of which erythrocyte membrane derived glycophorin is a major component.

Obesity, haemostasis and the fibrinolytic system

Obese patients are at risk for the development of cardiovascular diseases, which can in part be explained by disturbances in the haemostatic and fibrinolytic systems. Indeed, obese subjects tend to have higher values of fibrinogen, factor VII, factor VIII, von Willebrand factor and plasminogen activator inhibitor compared to non-obese subjects. Abdominal obesity, in particular, has been shown to be associated with disturbances in fibrinogen, factor VIII and von Willebrand factor, while less consistent results have been found for factor VII. Recently it has been demonstrated that the adipocyte itself is able to produce plasminogen activator inhibitor-1, possibly explaining the high levels found in obesity. Different studies have investigated the association between haemostatic and fibrinolytic parameters and the insulin resistance syndrome, often present in obese subjects. Fibrinogen has been found to be related to insulin, but it has been suggested that this relationship is not independent of the accompanying inflammatory reaction. Results from studies on the relationship between insulin resistance and factor VII, factor VIII and von Willebrand factor levels are inconsistent. In contrast, plasminogen activator inhibitor-1 has been found to correlate with all components of the insulin resistance syndrome, and can be considered as a true component of this metabolic syndrome. Weight loss seems to have a beneficial effect on factor VII--probably mediated through a reduction in triglycerides. Data on factor VIII and von Willebrand factor are scarce but weight loss does not seem to have an effect. Fibrinogen does not seem to be reduced by modest weight loss and a more substantial weight loss seems necessary to lower fibrinogen levels. In contrast, both modest and substantial weight loss have been found to significantly reduce plasminogen activator inhibitor-1 levels. In conclusion, the increased cardiovascular risk observed in obesity could in part be explained by the association between insulin resistance and components of the fibrinolytic and haemostatic systems. Whether this relationship is truly causal or indirect needs to be elucidated further.

Plasminogen activator inhibitor-1 in girls with precocious pubarche: a premenarcheal marker for polycystic ovary syndrome?

In both obese and nonobese women, polycystic ovary syndrome (PCOS) is essentially a disorder of hyperinsulinemic insulin resistance, and it may be heralded by precocious pubarche (PP; appearance of pubic hair in girls aged <8 y). The risk of progression from PP to PCOS is related to low birth weight, but there are no early biochemical markers of this risk. As increased plasminogen activator-inhibitor type 1 (PAI-1) activity (act) is an early marker of cardiovascular risk in PCOS, we have sought abnormalities in young girls with PP. In 33 young PP girls (age range 6-11 y), PAI-1-act was increased (mean + SEM: 15.6 +/- 1.5 IU/mL) compared with age-, sex-, and pubertal stage-matched controls (n = 13, 10.7 +/- 1.9, p < 0.05). PAI-1-act levels were inversely related to birth weight SD score (r = -0.33, p < 0.05), and PAI-1-act levels were therefore higher in PP girls with low birth weights (n = 14, 19.5 +/- 2.5 IU/mL) than normal birth weights (n = 19, 12.8 +/- 1.5, p < 0.01). During longitudinal observation in 10 PP girls (mean time interval 2.7 y), PAI-1-act levels in early puberty were positively related to postmenarcheal insulin levels (mean serum insulin SDS postoral glucose, r = 0.65, p < 0.05), and showed a similar relationship to postmenarcheal testosterone levels (r = 0.61, p = 0.06). Together with low birth weight, increased plasma PAI-1-act levels in early pubertal PP girls may indicate those girls with greater risk of developing hyperinsulinemic-hyperandrogenism features of PCOS.

Fruit and vegetables and cardiovascular risk profile: a diet controlled intervention study

OBJECTIVE

To evaluate the effect of fruit and vegetables consumption on markers of risk for cardiovascular disease.

DESIGN

Randomised, diet controlled, parallel study.

SUBJECTS

Forty-eight apparently healthy (40--60 y) volunteers with a low usual consumption of fruit and vegetables. Forty-seven of them completed the study.

INTERVENTIONS

During 4 weeks 24 volunteers consumed a standardised meal, consisting of 500 g/day fruit and vegetables and 200 ml/day fruit juice ('high' group) and 23 volunteers consumed 100 g/day fruit and vegetables ('low' group) with an energy and fat controlled diet.

RESULTS

Final total cholesterol was 0.2 (95% CI -0.5--0.03) mmol/l lower in the high group than in the low group (P>0.05). Final fibrinogen and systolic blood pressure were 0.1 (-0.1--0.4) g/l and 2.8 (-2.6--8.1) mmHg higher in the high group than in the low group (P>0.05), respectively. Also, other final serum lipid concentrations, diastolic blood pressure and other haemostatic factors did not differ between both groups.

CONCLUSIONS

This was a small randomised well-controlled dietary intervention trial of short duration with a considerable contrast in fruit and vegetable consumption. No effects on serum lipids, blood pressure and haemostatic variables were observed.

New diagnostic criteria for diabetes and coronary artery disease: insights from an angiographic study

OBJECTIVES

The goal of this research was to study coronary atherosclerosis in patients with type 2 diabetes compared with patients without diabetes according to the new definition of diabetes advocated by the American Diabetes Association in 1997.

BACKGROUND

Patients with diabetes (fasting plasma glucose above 7.0 mM/L) have a higher risk of cardiovascular death. The correlation with the pattern and severity of their coronary atherosclerosis, especially in the new patients with "mild" diabetes (7.0 mM/L < or = fasting plasma glucose < 7.8 mM/L), remains unclear.

METHODS

A cohort of 466 patients undergoing coronary angiography but free of any previous infarction, coronary intervention and insulin therapy were prospectively recruited. Ninety-three had diabetes (fasting plasma glucose > 7.0 mM/L or hypoglycemic oral treatment). Five angiographic indexes were calculated to describe severity and extent of coronary atherosclerosis.

RESULTS

Overall, patients with diabetes had more diffuse coronary atherosclerosis, a greater prevalence of mild, moderate and severe stenoses and a two-fold higher occlusion rate than patients without diabetes, even after adjustment for age, gender, body mass index, hypertension, lipid parameters, smoking, family history of cardiovascular events and ischemic symptoms. Patients with "mild diabetes" had a coronary atherosclerosis pattern more similar to patients with normal fasting plasma glucose than to patients formerly defined as diabetic according to the World Health Organization criteria, except that they had a higher prevalence of <50% stenoses.

CONCLUSIONS

In patients with type 2 diabetes, those with 7.0 mM/L < or = fasting plasma glucose < 7.7 mM/L have a slightly greater prevalence of mildly severe lesions that may partly explain their higher cardiovascular event rate.

Effects of comicronised fenofibrate on lipid and insulin sensitivity in patients with polymetabolic syndrome X

BACKGROUND

This study investigated the effects of comicronised fenofibrate in patients with dyslipidemia and polymetabolic syndrome X.

DESIGN

After a 6-week dietary run-in phase, 37 male patients eligible on lipid criteria entered a 12-week treatment phase consisting of diet plus one capsule daily containing 200 mg of comicronised fenofibrate (Lipanthyl(R)).

RESULTS

A significant reduction in plasma concentrations of total cholesterol, LDL cholesterol and triglyceride was observed after 4, 8 and 12 weeks of treatment with fenofibrate. The improvement in the atherogenic index LDL/HDL cholesterol from a pretreatment 3.8 to 3.0 after treatment was highly statistically significant and may be judged as satisfactory. Significant changes were also observed in haemostatic factors (fibrinogen reduced by 19%, factor VII activity reduced by 18%). Fasting serum insulin levels and insulin response (area under the curve) after oral glucose load were significantly reduced by 26.8% and 18.7%, respectively, indicating an improvement of insulin sensitivity. Systolic and diastolic blood pressure were significantly reduced. Uric acid was significantly reduced by 21.6%.

CONCLUSION

These favourable effects of comicronised fenofibrate both on lipid and non lipid parameters, including insulin sensitivity, may confer to this product a particular interest in the treatment of patients with polymetabolic syndrome X.

Job strain and risk indicators for cardiovascular disease in young female nurses

This study examined the possible effects of job demands, decision latitude, and job-related social support on risk indicators for cardiovascular disease (CVD) in 165 female nurses. Job strain was measured with the Job Content Questionnaire; CVD risk was measured with insulin, total cholesterol, triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), fibrinogen, tissue-type plasminogen activator (tPA) antigen, tPA activity, plasminogen activator inhibitor-1 antigen, and blood pressure. Multivariate analysis of covariance and regression analyses revealed no effects of either job strain or social support on these risk indicators. All risk indicators deteriorated with age and body mass index. Oral contraceptive use improved fibrinolytic potential and increased HDL-C but had adverse effects on TG levels. Results suggest that in healthy young women job strain is not associated with an unfavorable metabolic or fibrinolytic risk profile.

Effects of tibolone and continuous combined hormone replacement therapy on parameters in the clotting cascade: a multicenter, double-blind, randomized study

OBJECTIVE

To determine the effects of tibolone and continuous combined HRT (ccHRT) on parameters in the clotting cascade.

DESIGN

Randomized, double-blind study.

SETTING

Hemostasis unit of a university hospital clinic in Germany.

PATIENT(S)

Sixty healthy postmenopausal women.

INTERVENTION(S)

Twenty-nine subjects were treated with tibolone (2.5 mg/d) and 31 with oral ccHRT containing estradiol (2 mg/d) + estriol (1 mg/d) + norethindrone acetate (1 mg/d).

MAIN OUTCOME MEASURE(S)

Effects on parameters in the clotting cascade at baseline and after 12 and 24 weeks of treatment.

RESULT(S)

Tibolone increased fibrinolysis parameters without significantly altering coagulation parameters. Treatment with ccHRT resulted in a stimulating effect on parameters of both fibrinolysis and coagulation. Tibolone showed a stronger reduction of factor VII activity; less reduction of AT-III, protein C activity, and protein S activity; stronger increase of the activated partial thromboplastin time, plasminogen and plasminogen-antiplasminogen complexes; and less increase of D-Dimer than ccHRT. Both preparations similarly reduced climacteric complaints, whereas tibolone showed less breast complaints than ccHRT.

CONCLUSION(S)

This study confirms that tibolone, and to a lesser extent also ccHRT, changes hemostasis parameters toward a more fibrinolytic profile, which may diminish the risk of venous thrombosis.

High levels of nonesterified fatty acids are associated with increased familial risk of cardiovascular disease

To address the question of whether elevated concentrations of nonesterified fatty acids (NEFAs) are associated with an increased risk of cardiovascular disease, we measured NEFA concentrations in 140 diabetic and 343 nondiabetic unrelated Swedish subjects with a family history of type 2 diabetes and related the findings to history of cardiovascular disease in their parents. Parents of nondiabetic offspring belonging to the quartile of highest NEFA concentrations had a higher risk of myocardial infarction (35% versus 16%, P<0.01) and stroke (45% versus 16%, P<0.0005) than did parents of offspring from the lowest NEFA quartile. In a multiple logistic regression analysis, a high NEFA concentration in offspring was significantly associated with myocardial infarction and stroke in their parents. No such relationship was observed between diabetic offspring and their parents. Assuming that the same relationship between NEFA concentrations and cardiovascular disease is seen in the offspring and their parents, the findings suggest that elevated NEFA concentration is a risk factor for cardiovascular disease and could be pathogenically involved in the atherosclerotic process.

The relationship between fibrinogen and other coronary heart disease risk factors in a Chinese population

Few studies have examined fibrinogen in Chinese populations in which the incidence of coronary heart disease (CHD) is lower than that in the West. This study aimed to examine the relationship between fibrinogen and other CHD risk factors in Hong Kong Chinese. Fibrinogen was measured by the Clauss method in 1359 men and 1405 women aged 25-74 years, randomly selected from the Hong Kong population. Mean fibrinogen level increased with age, from 2.22 g/l in those aged 25-34 years to 2.76 g/l in 65-74 years in men, and from 2.42 to 2.94 g/l respectively in women. The most important factors associated with fibrinogen were age, obesity and blood lipid levels in both genders. In men, smoking was associated with higher fibrinogen levels and cessation of smoking with lower levels. Prospective studies are needed to examine the role of fibrinogen in CHD in Chinese and other Asian populations.

A randomized controlled double-blind study of the effects on hemostasis of two progestogen-only pills containing 75 microgram desogestrel or 30 microgram levonorgestrel

The effects of two progestogen-only pills containing either 75 microgram desogestrel (DSG) or 30 microgram levonorgestrel (LNG) on hemostasis were investigated in a double-blind, randomized, controlled study of seven treatment cycles in 78 healthy women. DSG reduced factor VII activity (p < 0.05) and prothrombin fragment 1+2 (p < 0.05) and increased protein S (p < 0.001). LNG reduced factor VII activity (p < 0.01) and plasminogen activity (p < 0.01) and increased tissue-plasminogen activator (t-PA) (p < 0.05). At the end of the post-treatment cycle with DSG, protein S (p < 0.01) and t-PA (p < 0.05) were increased and plasminogen activity was decreased (p < 0.05), whereas with LNG, t-PA was increased (p < 0.001) and prothrombin fragment 1+2 (p < 0.05) and plasminogen activity (p < 0.001) were decreased. Between-group comparisons revealed higher values for DSG regarding the anticoagulatory parameter protein S at cycle 7 (p < 0.01) and post-treatment assessments (p < 0.05), and the fibrinolytic parameter plasmin-antiplasmin complex was higher with DSG at cycle 7 (p < 0.05) and at post-treatment (p < 0.05). Both preparations had comparable and potentially favorable effects of hemostasis, and may offer suitable hormonal contraception to women with a personal or family history of venous thromboembolic diseases.

Cardiovascular risk factors in relation to cigarette smoking: a population-based survey among Asians in Singapore

To investigate how cigarette smoking increases the risk of cardiovascular disease, risk factors were compared between 166 cigarette smokers and 312 non-smokers, in a random sample of males (Chinese, Malays and Asian Indians) aged 30-69 years from the general population of Singapore. There was adjusted for age and ethnic group. The prevalence of hypertension was lower in cigarette smokers (15.2%) than non-smokers (21.9%), with the difference reduced by adjustment for body mass index (BMI). Smokers had: lower mean serum HDL-cholesterol (0.76 versus 0.81 mmol/l) and higher mean serum fasting triglyceride (1.92 versus 1.71 mmol/l), which will increase atherosclerosis; higher mean plasma fibrinogen (2.75 versus 2.67 g/l) and plasminogen activator inhibitor 1 [PAI-1] (24.9 versus 22.2 ng/ml), which will increase thrombosis; and lower mean plasma vitamin C (4.4 versus 6.4 mg/l) and serum selenium (118 versus 123 microg/l), which may increase atherosclerosis. Adjustment for BMI slightly increased the differences for HDL-cholesterol, fasting triglyceride, fibrinogen and PAI-1, indicating that less generalised obesity among smokers reduces their increased cardiovascular disease risk. Smoking was not found to be related to: diabetes mellitus; serum total cholesterol, LDL-cholesterol, apolipoproteins A1 and B and lipoprotein(a); plasma factor VIIc and prothrombin fragment 1 + 2; and plasma vitamins A and E and serum ferritin. There was no evidence of increased insulin resistance in smokers, as measured by mean fasting serum insulin.

[Tobacco smoking and cardiovascular risk]

Cigarette smoking is firmly established as a risk factor for coronary heart disease, stroke and peripheral vascular disease, and is associated with increased cardiovascular mortality. A possible explanation for this relation is that smoking increases the development of atherosclerosis. Indeed, tobacco smoking has been associated with modified lipids levels, decreased fibrinolysis, increased fibrinogen levels and changes in endothelial and platelet functions for instance, which are themselves either known risk factors for or early features of atherosclerosis. Passive smoking, defined as the the involuntary exposure of non-smokers to tobacco combustion products in the indoor environment is now convincingly linked to heart disease mortality and morbidity. Stopping smoking works, decreasing cardiovascular mortality and morbidity within 5 years, whatever the age and sex of the previous smoker.

Haptoglobin polymorphism, a genetic risk factor in coronary artery bypass surgery

Haptoglobin (Hp) 2-2 type has been associated with accumulation of atherosclerotic lesions in essential hypertension. The aim of this study was to investigate the relationship between Hp type and the extension of coronary lesions in 765 male patients who underwent coronary artery bypass grafting (CABG). In this group, relative Hp1 (0.418) and Hp2 (0.582) allele frequencies were comparable with those of the reference population. Candidate CABG patients with a Hp 2-2 type were overrepresented in the younger (< 45 years) age group (P < 0.05). Hp 2-2 patients needed more bypass grafts than Hp 1-1 patients (relative risk 1.92 95% C.I. 1.24-2.96). The Hp 2-2 type was overrepresented among victims of a previous acute myocardial infarction (P < 0.05) and among patients with a lower (< 45 years) age at infarction (P < 0.05). In patients who already underwent a previous CABG graft survival time was shortest in Hp 2-2 type (P < 0.05). Patients with a Hp 2-2 type more likely develop atherosclerotic lesions despite comparable serum lipid concentrations.