Interleukin-6 as a predictor of symptom resolution in psychological distress: a cohort study

BACKGROUND

Elevated levels of interleukin-6 (IL-6) have been associated with the development of common mental disorders, such as depression, but its role in symptom resolution is unclear.

METHOD

We examined the association between IL-6 and symptom resolution in a non-clinical sample of participants with psychological distress.

RESULTS

Relative to high IL-6 levels, low levels at baseline were associated with symptom resolution at follow-up [age- and sex-adjusted risk ratio (RR) = 1.15, 95% confidence interval (CI) 1.06-1.25]. Further adjustment for covariates had little effect on the association. Symptomatic participants with repeated low IL-6 were more likely to be symptom-free at follow-up compared with those with repeated high IL-6 (RR = 1.21, 95% CI 1.03-1.41). Among the symptomatic participants with elevated IL-6 at baseline, IL-6 decreased along with symptom resolution.

CONCLUSIONS

IL-6 is potentially related to the mechanisms underlying recovery from symptoms of mental ill health. Further studies are needed to examine these mechanisms and to confirm the findings in relation to clinical depression.

Prevention and treatment of venous thromboembolism--International Consensus Statement

The aim of this document is to provide a clear and concise account of the evidence regarding efficacy or harm for various methods available to prevent and manage venous thromboembolism (VTE).

Do women exhibit greater differences in established and novel risk factors between diabetes and non-diabetes than men? The British Regional Heart Study and British Women's Heart Health Study

AIMS/HYPOTHESIS

Type 2 diabetes is associated with greater relative risk of CHD in women than in men, which is not fully explained by conventional cardiovascular risk factors. We assessed whether cardiovascular risk factors including more novel factors such as markers of insulin resistance, inflammation, activated coagulation and endothelial dysfunction differ more between diabetic and non-diabetic women than between diabetic and non-diabetic men, and the role of insulin resistance.

METHODS

A cross-sectional study of non-diabetic and diabetic men and women (n = 7,529) aged 60-79 years with no previous myocardial infarction who underwent an examination was conducted. Measurements of anthropometry, blood pressure and fasting measurements of lipids, insulin, glucose and haemostatic and inflammatory markers were taken.

RESULTS

Non-diabetic women tended to have more favourable risk factors and were less insulin resistant than non-diabetic men, but this was diminished in the diabetic state. Levels of waist circumference, BMI, von Willebrand factor (VWF), WBC count, insulin resistance (HOMA-IR), diastolic blood pressure, HDL-cholesterol, tissue plasminogen activator (t-PA) and factor VIII differed more between diabetic and non-diabetic women than between diabetic and non-diabetic men (test for diabetes × sex interaction p < 0.05). The more adverse effect of diabetes on these risk markers in women was associated with, and thereby largely attenuated by, insulin resistance.

CONCLUSIONS/INTERPRETATION

The greater adverse influence of diabetes per se on adiposity and HOMA-IR and downstream blood pressure, lipids, endothelial dysfunction and systemic inflammation in women compared with men may contribute to their greater relative risk of coronary heart disease.

Sex differences in the relationship between inflammatory and hemostatic biomarkers and metabolic syndrome: British 1958 Birth Cohort

BACKGROUND

Circulating levels of C-reactive protein (CRP), fibrinogen, fibrin D-dimer, tissue plasminogen activator antigen (t-PA) and von Willebrand factor (VWF) are associated with incident coronary heart disease (CHD). However, their associations with metabolic syndrome and its components in large populations of men and women have not been well defined.

OBJECTIVES

We compare the sex associations of these biomarkers with established CHD risk factors, metabolic syndrome and its components in a large cohort.

PATIENTS AND METHODS

8302 men and women aged 45 years from the British 1958 birth cohort provided a blood sample. Analyses were restricted to 3457 men and 3464 women with complete data on all risk factors and no history of cardiovascular disease. Multiple regression analyses adjusted for smoking, social class, alcohol consumption and variables related to biomarker measurement error.

RESULTS

Adjusted sex differences in levels of all biomarkers (except VWF) varied according to presence/absence of metabolic syndrome, its components and obesity (BMI ≥30 kg m(-) (2)). Associations in women were up to twice as strong for CRP, fibrinogen and t-PA with markers of obesity (body mass index, waist circumference), blood pressure, blood lipids and metabolic syndrome. D-dimer showed weaker associations and less heterogeneity by sex. There was no evidence of sex interaction in associations with VWF.

CONCLUSIONS

Associations between CRP, fibrinogen and t-PA and metabolic syndrome and its components were stronger in women than in men. Understanding the reasons for these differences across sex will be important in understanding the pathophysiology of cardiovascular and metabolic disease in men and women.

Effects of short-term therapy with glibenclamide and repaglinide on incretin hormones and oxidative damage associated with postprandial hyperglycaemia in people with type 2 diabetes mellitus

AIM

To examine the effects of glibenclamide and repaglinide on glucose stimulated insulin release, incretins, oxidative stress and cell adhesion molecules in patients with type 2 diabetes suboptimally treated with metformin.

METHODS

A randomized clinical trial was performed recruiting 27 subjects (HbA(1c) between 7.5 and 10.5%) free from cardiovascular and renal disease. Glucose, insulin, C-peptide, glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic peptide (GIP), total antioxidant status, F(2)-isoprostane, interleukin-6 and cell adhesion molecules were measured during an oral glucose load at baseline and after eight weeks of treatment. The areas under the curve were analysed at 45, 60 and 120 min (AUC(45), AUC(60), AUC(120)).

RESULTS

Significant improvements in glucose were observed with repaglinide (HBA(1c): -1.5%, fasting glucose: -2.8 mmol/L, 2-h glucose: -3.7 mmol/L, AUC(120): -18.9%) and glibenclamide (-1.0%, -2.2 mmol/L, -2.5 mmol/L, -17.5%). Repaglinide was also associated with an increase in the AUC(60) and AUC(120) for insulin (+56%, +61%) and C-peptide (+41%, +36%). GLP-1, GIP, IL-6, ICAM-1 and E-selectin levels did not change in either group. No association was observed between GLP-1, GIP-1 and plasma markers of oxidative stress.

CONCLUSION

Repaglinide is associated with improved postprandial glycaemic control via insulin and C-peptide release. We observed no direct effects of glibenclamide or repaglinide on plasma levels of GLP-1 or GIP. We observed no associations of GLP-1 and GIP with plasma markers of oxidative stress.

Changes in C-reactive protein levels before type 2 diabetes and cardiovascular death: the Whitehall II study

OBJECTIVE

Prospective studies show that high C-reactive protein (CRP) levels predict diabetes and cardiovascular disease (CVD), but changes in this marker preceding disease onset are not well characterized. This study describes CRP trajectories prior to type 2 diabetes onset and fatal CVD.

METHODS

In a prospective cohort of 7350 British civil servants (70% male, mean age 51 years), 558 incident type 2 diabetes cases (75-g oral glucose tolerance test, doctor's diagnosis, or self-report) and 125 certified fatal cardiovascular events were observed during a median follow-up of >14 years. Trajectories of logarithmically transformed CRP levels prior to incident diabetes or fatal cardiovascular event (cases), or the end of follow-up (controls) were calculated using multilevel modeling.

RESULTS

Baseline CRP levels were higher among participants who developed diabetes (median (interquartile range) 1.44 (2.39) vs 0.78 (1.21) mg/l) or fatal CVD (1.49 (2.47) vs 0.84 (1.30) mg/l) compared with controls (both P<0.0001). In models adjusted for age, sex, body mass index, ethnicity, and employment grade, CRP levels increased with time among both incident diabetes cases and controls (P<0.0001), but this increase was less steep for cases group (P<0.05). CRP levels followed increasing linear trajectories in fatal cardiovascular cases and controls (P<0.0001) with no slope difference between the groups.

CONCLUSIONS

CRP levels were higher among those who subsequently developed diabetes or died from CVD. For type 2 diabetes, age-related increase in CRP levels was less steep in the cases group than in controls, whereas for fatal CVD these trajectories were parallel.

Fetal corticotrophin-releasing hormone mRNA, but not phosphatidylserine-exposing microparticles, in maternal plasma are associated with factor VII activity in pre-eclampsia

BACKGROUND

Pre-eclampsia is associated with increased placental debris circulating in maternal plasma.

OBJECTIVES

This study related placental debris to maternal markers of coagulation and endothelial activation in pre-eclampsia.

PATIENTS/METHODS

Circulating fetal corticotrophin-releasing hormone (CRH) mRNA and phosphatidylserine (PS)-exposing microparticles were assayed in third trimester plasma from women with pre-eclampsia (n = 32) and controls (n = 32) matched for age, body mass index, parity, and gestational age at sampling. Markers of maternal hemostasis and endothelial function were assessed.

RESULTS

Fetal CRH mRNA levels were higher in pre-eclampsia [mean 0.75 (SD 2.77) CRH/glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA ratio] than in control pregnancies [0.20 (0.74), P = 0.014]. PS-exposing microparticle levels were not different between the groups. Women with pre-eclampsia had higher levels of tissue factor pathway inhibitor (TFPI), prothrombin F(1+2) fragment (F(1+2)), factor XIIa, soluble vascular cell adhesion molecule 1, von Willebrand factor and plasminogen activator inhibitor 1 than controls. Fetal CRH mRNA correlated with TFPI in pre-eclampsia and control groups (r = 0.38, P = 0.031, and r = 0.37, P = 0.039, respectively). Fetal CRH mRNA correlated with FVII activity (r = 0.43, P = 0.017) and PS-exposing microparticles correlated inversely with F(1+2) (r = -0.64, P < 0.001) in pre-eclampsia.

CONCLUSIONS

Placental debris, assessed by fetal CRH mRNA levels in maternal blood, is related to coagulation potential, i.e. FVII activity, but not to markers of coagulation or endothelial activation in pre-eclampsia.

Associations of adiponectin with metabolic and vascular risk parameters in the British Regional Heart Study reveal stronger links to insulin resistance-related than to coronory heart disease risk-related parameters

BACKGROUND AND AIM

Adiponectin is considered by many to be part of the 'common soil' linking type 2 diabetes and coronary heart disease (CHD). We examined the relationship between adiponectin and insulin resistance, metabolic, inflammatory and haemostatic risk factors and hepatic function.

METHODS AND RESULTS

The study was carried out in 3640 non-diabetic men aged 60-79 years drawn from general practices in 24 British towns and who were not on warfarin. Adiponectin was associated with waist circumference (inversely), alcohol intake (positively) and physical activity (nonlinearly); no association was seen with cigarette smoking, prevalent CHD or stroke. After adjustment for these factors, adiponectin was significantly inversely associated with insulin resistance, triglyceride, C-reactive protein (but not interleukin 6), tissue plasminogen activator and alanine aminotransferase and positively associated with high-density lipoprotein cholesterol (HDL-cholesterol) and Factor VIII, factors associated with diabetes. No association was seen with cholesterol, smoking, systolic blood pressure or coagulation factors. Risk of the metabolic syndrome decreased significantly with increasing adiponectin.

CONCLUSION

Adiponectin is inversely associated with factors strongly associated with the development of diabetes. Limited associations with the established major risk factors for CHD suggest adiponectin may be a stronger marker of risk for diabetes than for CHD.

Length of docked tail and the incidence of rectal prolapse in lambs

A multistate cooperative study was conducted to study the current issue of tail length in docked lambs and its relationship to incidence of rectal prolapse. A total of 1,227 lambs at six locations were randomly allocated to two or three tail dock treatments: 1) short--tail was removed as close to the body as possible, 2) medium--tail was removed at a location midway between the attachment of the tail to the body and the attachment of the caudal folds to the tail, and 3) long--tail was removed at the attachment of the caudal folds to the tail. Short-docked lambs had a greater (P < 0.05) incidence of rectal prolapse (7.8%) than lambs with a medium (4.0%) or a long (1.8%) dock. Female lambs had a higher (P < 0.05) incidence of rectal prolapse than male lambs. At two stations, lambs were finished either in a feedlot on a high-concentrate diet or on pasture with no grain supplementation. At one station, with a very low incidence of rectal prolapse, there was no difference in incidence between lambs finished in the feedlot or on pasture; however, at the station with a relatively high incidence of rectal prolapse, lambs in the feedlot had a higher (P < 0.05) incidence than lambs on pasture. The half-sib estimate of heritability for the incidence of rectal prolapse was low (0.14). The results of this study strongly implicate short dock length as a cause of rectal prolapse in lambs finished on high-concentrate diets. Furthermore, the results of this study and the only other study known conducted on this issue strongly suggest that docking lambs at the site of the attachment of the caudal folds to the tail will result in a negligible incidence of rectal prolapse.

Impact of angiotensin converting enzyme inhibition on post-coronary artery bypass interleukin 6 release

BACKGROUND

Angiotensin 1 converting enzyme (ACE) inhibitors reduce morbidity and mortality after coronary artery bypass graft surgery (CABG). This benefit may result from an anti-inflammatory action.

OBJECTIVE

To examine the effect of ACE inhibition on interleukin 6 (IL-6) concentrations after CABG.

PATIENTS AND METHODS

161 patients undergoing elective first time CABG were recruited, of whom 41 (25%) were receiving ACE inhibitor treatment; 21 patients with confounding postoperative complications were excluded. After these exclusions there were 33 patients (24%) on ACE inhibitor treatment. Plasma IL-6 was measured preoperatively and again six hours after CABG.

RESULTS

Baseline IL-6 concentrations (geometric mean (SEM)) were non-significantly lower among the patients receiving ACE inhibitors (3.7 (0.1) v 4.3 (0.1) pg/ml, p = 0.12). Overall, post-CABG IL-6 concentrations increased significantly (mean rise 177 (12) pg/ml, p < 0.0005). This response was blunted among ACE inhibitor treated patients. Median increases in IL-6 concentrations were 117 v 193 pg/ml, for treated v non-treated patients, respectively (Kruskal-Wallis, p = 0.02), with peak postoperative IL-6 concentrations lower among the subjects receiving ACE inhibitors than in untreated subjects (142 (19) v 196 (13) pg/ml, p = 0.02). The effect of ACE inhibitors remained significant after multivariate analysis (p = 0.018).

CONCLUSIONS

ACE inhibitor treatment is associated with a reduction in IL-6 response to CABG. The data suggest that this class of drug may have a direct anti-inflammatory effect, which could explain some of its clinical benefit.

Lifestyle factors and coagulation activation markers: the Caerphilly Study

Coagulation activation markers are being investigated as risk factors for cardiovascular disease; we examined the contribution of several lifestyle factors to variation in plasma levels of several activation markers measured in a population-based study of 1947 men. Smoking, alcohol, body mass index (BMI), leisure and work activity, social class, and use of prescribed medicines were each examined in turn. Specific assays of fibrin D-dimer and von Willebrand factor (vWF) activity showed similar relationships to lifestyle variables as we observed previously for less specific assays of D-dimer and vWF antigen. D-dimer levels increased with age, in smokers and in men taking prescribed medication, and were negatively associated with leisure time activity. vWF activity increased with age and showed a U-shaped distribution with BMI. Factors VIIc and VIIIc and thrombin-antithrombin complexes were associated with BMI, factor VIIIc and prothrombin fragments 1 + 2 (F1 + 2) were associated with age, activated partial thromboplastin time (aPTT) and F1 + 2 were associated with smoking, and aPTT showed a small negative association with alcohol consumption. We conclude that lifestyle modification has the possibility of favourably influencing several of these risk markers. In particular, cigarette smoking has a possibly reversible effect on coagulation activation (measured by F1 + 2 and D-dimer).

The relationship between infection, inflammation, and cardiovascular disease: an overview

Atherosclerotic plaques were likened histologically to healing inflammatory lesions by Russell Ross, who proposed a "response to injury" hypothesis for their formation. More recently, intraplaque inflammation has been postulated to play a role in thinning of the fibrous cap, plaque rupture, and superadded thrombosis. Potential causes for vascular injury include mechanical stress, smoke exposure, hypercholesterolemia, hyperhomocysteinemia, and chronic infection (direct, or indirect). Blood levels of inflammatory markers (e.g., C-reactive protein [CRP]; serum amyloid A [SAA]; fibrinogen; plasma viscosity; erythrocyte sedimentation rate [ESR]; leukocyte count, low serum albumin) have been associated with vascular risk factors and with prevalent and incident atherothrombotic cardiovascular disease (CVD) (coronary heart disease, [CHD]; stroke; and peripheral arterial disease). More recently, cytokines (e.g., interleukin-6 [IL-6]) and soluble adhesion molecules (e.g., intercellular adhesion molecule-1, vascular cell adhesion molecule-1) have been associated with both risk factors and disease; and offer potential therapeutic targets for nonspecific "anti-inflammatory" treatment of arterial disease. Infections associated with arterial disease include specific infections (Chlamydia pneumoniae, Helicobacter pylori) and nonspecific infections (periodontal infections, respiratory tract infections). Recent meta-analyses have shown that associations of serum markers of C. pneumoniae and H. pylori with arterial disease, risk factors, or potential intermediary mechanisms for disease are weaker than was first suggested by early reports. Likewise, further studies and meta-analyses are required to evaluate the epidemiologic relationships of CVD to periodontal infection and disease and to chronic pulmonary infections and disease. The weaker the associations between chronic infections and CVD, the larger is the size of randomized controlled trials required to establish (or exclude) a preventive effect of infection treatment. While control of chronic infection in the mouth, stomach or lungs is appropriate for its local effects, proving its efficacy in prevention of CVD presents a continuing challenge to medical science.

The role of myocardial perfusion scanning, heart rate variability and D-dimers in predicting the risk of perioperative cardiac complications after peripheral vascular surgery

OBJECTIVES

To study the value of a number of proposed prognostic factors in prediction of the risk of perioperative cardiac events after vascular surgery.

DESIGN AND METHODS

Two hundred and ninety-seven patients undergoing peripheral vascular surgery were prospectively studied. Patients underwent preoperative 24 h ambulatory electrocardiography, measurement of haemostatic variables, myocardial assessment of perfusion by dipyridamole-thallium scintigraphy and radionuclide ventriculography. The primary endpoint was cardiac death or nonfatal myocardial infarction within 30 days of surgery. A combined endpoint included the primary endpoint plus occurrence of cardiac failure, unstable angina or serious arrhythmias.

RESULTS

The primary endpoint occurred in 21 (7%), and the combined endpoint in 41 (14%) of patients. On multivariate analysis, increased age, previous myocardial infarction, aortic surgery, impaired heart rate variability and a positive thallium scan were independent predictors of primary end-points. Preoperative atrial fibrillation and increased fibrin D-dimer were additional predictors of the combined endpoint. Construction of receiver-operator characteristic curves to examine the incremental value of predictive models showed that sensitivity and specificity of clinical data alone for primary endpoints was 71% and 72% respectively, while for the full model (incorporating heart rate variability and thallium data) this rose to 84% and 80% (p=0.0001).

CONCLUSIONS

Preliminary screening using clinical data has limited value in risk assessment prior to vascular surgery but preoperative heart rate variability, D-dimers and thallium scanning provide modest incremental predictive value.

Haemostasis in ischaemic stroke and vascular dementia

Abnormalities of coagulation and fibrinolysis may play an important role in the pathogenesis of ischaemic stroke and vascular dementia. We aimed to determine whether haemostatic function is altered in acute recent-onset or chronic ischaemic cerebrovascular disease. We studied consecutive patients with ischaemic stroke (n = 74) and vascular dementia (n = 42) compared with healthy controls (n = 40) in a case-control study. The ischaemic stroke group was assessed twice, 3-10 days after the acute stroke and at 1-3 months. Fibrinogen, fibrin D-dimer (marker of fibrin turnover) and von Willebrand factor (vWF) (marker of endothelial disturbance) were elevated acutely (P < 0.0001) and in the convalescent phase after ischaemic stroke (P < 0.0001, P < 0.0001, and P < 0.01 respectively, compared with controls). Similar results were seen in the vascular dementia group. Stepwise multivariate regression analyses showed that cerebrovascular disease correlated independently with fibrinogen (P < 0.001) and fibrin D-dimer levels (P < 0.001), while vWF correlated independently with electrocardiograph evidence of ischaemic heart disease (P = 0.004). Changes between acute and convalescent phases in ischaemic stroke were slightly inconsistent. However, in the acute stage there were tendencies for fibrinogen, D-dimer and vWF to be increased, and factor VIII was significantly higher. Abnormalities of haemostasis, including increased fibrin turnover and endothelial disturbance, are found in both acute and chronic cerebral ischaemia. Many of these patients have co-existent ischaemic heart disease and this may contribute to some of these changes. Acute ischaemic stroke is associated with transient changes in haemostatic factors; however, most abnormalities persist into the convalescent phase, and are also demonstrable in subjects with vascular dementia.

How to search for the role and prevalence of defective fibrinolytic states as triggers of myocardial infarction? The haemostasis epidemiologist's view

The most useful phenotypic measures of fibrinolysis in prediction of myocardial infarction currently appear to be tissue-type plasminogen activator (t-PA) antigen and fibrin D-dimer. Recent meta-analyses of prospective studies show significant associations with incident ischaemic heart disease (including myocardial infarction) after adjustment for classical risk factors. The odds ratio in the top third versus the bottom third for baseline values was 1.5 (95% confidence interval 1.2-1.8) for t-PA antigen, and 1.7 (95% confidence interval 1.3-2.2) for D-dimer. Further studies are required to establish with confidence the associations for plasminogen activator inhibitor type 1, urokinase-type plasminogen activator, and other fibrinolytic variables.

Interleukin-6 gene -174g>c and -572g>c promoter polymorphisms are strong predictors of plasma interleukin-6 levels after coronary artery bypass surgery

Interleukin-6 (IL-6) synthesized in response to diverse stimuli may play an important role in bridging the inflammatory and atherosclerotic processes. The acute-phase response after coronary artery bypass graft surgery (CABG) is associated with the induction and release of cytokines, such as IL-6. We have examined the effect of common polymorphisms in the IL-6 gene promoter (-174G>C, -572G>C, and -597G>A) on IL-6 levels after elective CABG. DNA extracted from the peripheral blood of 127 patients was amplified by polymerase chain reaction. IL-6 genotypes were resolved by gel electrophoresis after restriction enzyme digestion. Serum IL-6 was measured before surgery and in serial samples at 6, 24, 48, and 72 hours after CABG. Genotype distribution was as expected for a population in Hardy-Weinberg equilibrium for all polymorphisms. Rare allele frequencies (+/-95% CIs) were similar to those reported previously: -597A 0.36 (0.30 to 0.42), -572C 0.07 (0.04 to 0.10), and -174C 0.37 (0.31 to 0.43). The -174G>C and -597G>A genotypes were in strong allelic association (Delta=0.97, P<0.001). Baseline IL-6 levels did not significantly differ between patients with different genotypes for any polymorphism. However, 6 hours after CABG, peak IL-6 levels were significantly higher (P=0.03) in carriers of the -572C allele than in those of the -572GG genotype (355+/-67 versus 216+/-13 pg/mL, respectively) and in those with genotype -174CC compared with -174G allele carriers (287+/-31 versus 227+/-15 pg/mL, respectively; P=0.04). These effects remained statistically significant after adjusting for possible confounders, including age, sex, smoking, duration of cardiopulmonary bypass, aortic cross-clamp time, and total duration of surgery. These data demonstrate that IL-6 promoter polymorphisms influence peak IL-6 production after CABG, suggesting that these polymorphisms, which are functional in vitro, are also functional in vivo, suggesting a genetic influence on IL-6 levels after acute severe injury.

Fibrin D-dimer, markers of coagulation activation and the risk of major ischaemic heart disease in the caerphilly study

We have previously reported that plasma fibrin D-dimer (a marker of turnover of cross-linked fibrin) showed a strong and independent association with incident ischaemic heart disease (IHD) in the Caerphilly Study cohort of 1,998 men aged 49-65. To establish the specificity of this finding, we assayed plasma samples from this cohort with a more specific assay for fibrin D-dimer: this showed an association with incident IHD which was at least as strong and independent as that for the original assay (odds ratio, OR for top fifth compared to bottom fifth 3.79; 95% CI 1.77-8.10; p < 0.0001). To establish potential causes of the increased fibrin turnover, we also assayed several potential markers of coagulation activation or thrombotic tendency (prothrombin fragment F1+2, thrombin-antithrombin complexes, factor VIIc, activated partial thromboplastin time [APTT] and activated protein C resistance): none of these variables were associated with incident IHD in this cohort. We suggest that further studies are required to establish the causes of increased cross-linked fibrin turnover, which is associated with incident IHD in the general population when measured by a specific assay.

Fibrinogen and its degradation products as thrombotic risk factors

Recent meta-analyses of prospective studies have shown that plasma levels of both fibrinogen and fibrin D-dimer are independent predictors of ischemic heart disease. Although at present reported studies using different assays do not show heterogeneity, there is a need for prospective comparison of different assays, as well as for development of standards. Collaborative development of the clinical use of these risk predictors is also required. Finally, the causal significance of the associations of fibrinogen and D-dimer with thrombotic events remains to be established by randomized controlled trials of reduction in their plasma levels.

Different effects of oral and transdermal hormone replacement therapies on factor IX, APC resistance, t-PA, PAI and C-reactive protein--a cross-sectional population survey

The effects of hormone replacement therapy (HRT) on thrombosis risk, thrombotic variables, and the inflammatory marker C-reactive protein (CRP) may vary by route of administration (oral versus transdermal). We studied the relationships of 14 thrombotic variables (previously related to cardiovascular risk) and CRP to menopausal status and to use of HRT subtypes in a cross-sectional study of 975 women aged 40-59 years. Our study confirmed previously-reported associations between thrombotic variables and menopausal status. Oral HRT use was associated with increased plasma levels of Factor IX, activated protein C (APC) resistance, and CRP; and with decreased levels of tissue plasminogen activator (t-PA) antigen and plasminogen activator inhibitor (PAI) activity. Factor VII levels were higher in women taking unopposed oral oestrogen HRT. The foregoing associations were not observed in users of transdermal HRT; hence they may be consequences of the "first-pass" effect of oral oestrogens on hepatic protein synthesis. We conclude that different effects of oral and transdermal HRT on thrombotic and inflammatory variables may be relevant to their relative thrombotic risk; and suggest that this hypothesis should be tested in prospective, randomised studies.

The prevalence of prophylaxis for deep vein thrombosis in acute hospital trusts

OBJECTIVE

The effectiveness of activities to promote routine prophylaxis to prevent thromboembolism is difficult to assess because information about the prevalence of prophylaxis is sparse. The aim of this study was to assess the prevalence of deep vein thrombosis (DVT) prophylaxis for patients at risk in general medicine, general surgery, orthopaedics and gynaecology in Scotland and the North of England.

DESIGN

Retrospective case note review of a random sample of episodes of care in a stratified random sample of directorates in Scotland and a convenience sample in England.

SETTING

Twenty acute hospital directorates in Scotland and eight in the North of England.

PARTICIPANTS

Case notes of patients at risk of thrombosis and discharged from the selected directorates in a 12-month period (n = 742).

MAIN OUTCOME MEASURES

The proportion of patients receiving prophylaxis in each directorate.

RESULTS

Overall, 469/526 (89%) of patients in Scotland and 199/216 (92%) in England received prophylaxis. The proportion varied from 71% in general medicine to 100% in orthopaedics. The frequency of use of different forms of prophylaxis varied between directorates. Approximately 60% of the patients who received prophylaxis received more than one form.

CONCLUSIONS

Prophylaxis for DVT is well established for procedures and conditions that are known to increase the risk of thrombosis and for which there are no contraindications. Additional efforts to promote prophylaxis for these conditions are unlikely to be cost effective. Further research is needed to establish whether rates are equally high in other conditions, and whether the high prophylaxis rates are due to clinical effectiveness initiatives.

Lipoprotein (a) and development of intermittent claudication and major cardiovascular events in men and women: the Edinburgh Artery Study

Lipoprotein (a) may be an important risk factor for atherosclerosis. It is widely accepted that lipoprotein (a) levels are raised in patients with coronary heart disease, but there is some doubt about the causality of the relationship. In addition, little is known about the relationship between lipoprotein (a) and either stroke or peripheral arterial disease, nor about the role of lipoprotein (a) in women. Subjects aged 55-74 years (n=1592) were selected at random from 11 general practices in Edinburgh, Scotland and followed up for 5 years. The incidences of myocardial infarction, intermittent claudication and stroke were 13.4, 9.4 and 3.7%, respectively. Raised lipoprotein (a) levels at baseline were associated with an increased risk (95% confidence interval) of myocardial infarction RR 1.15 (1.00, 1.32), intermittent claudication RR 1.32 (1.10, 1.57) but not significantly for stroke RR 1.24 (0.93, 1.64). This increased risk persisted for intermittent claudication after adjustment for baseline cardiovascular disease and other risk factors RR 1.20 (1.00, 1.43), but for myocardial infarction became non-significant RR 1.06 (0.91, 1.23). The risk of disease associated with raised lipoprotein (a) was slightly higher in women than in men, especially for intermittent claudication (men RR 1.09 (0.87, 1.36) compared to women RR 1.37 (1.01, 1.87)). In conclusion, we found that lipoprotein (a) was an independent predictor of cardiovascular events in both sexes. The association between lipoprotein (a) and cardiovascular events may have been stronger in women than in men, and for peripheral arterial disease than myocardial infarction and stroke.

Skin microvascular vasodilatory capacity in offspring of two parents with Type 2 diabetes

AIMS

Microvascular dysfunction occurs in Type 2 diabetes and in subjects with fasting hyperglycaemia. It is unclear whether this dysfunction relates to dysglycaemia. This study investigated in normogylcaemic individuals whether a genetic predisposition to diabetes, or indices of insulin resistance including endothelial markers, were associated with impaired microvascular function.

METHODS

Maximum microvascular hyperaemia to local heating of the skin was measured using laser Doppler flowmetry in 21 normoglycaemic subjects with no family history of diabetes (Group 1) and 21 normoglycaemic age, sex and body mass index-matched offspring of two parents with Type 2 diabetes (Group 2).

RESULTS

Although Group 2 had normal fasting plasma glucose and glucose tolerance tests, the 120-min glucose values were significantly higher at 6.4 (5.3-6.6) mmol/l (median (25th - 75th centile)) than the control group at 4.9 (4.6-5.9) mmol/l (P = 0.005) and the insulinogenic index was lower at 97.1 (60.9-130.8) vs. 124.0 (97.2-177.7) (P = 0.027). Skin maximum microvascular hyperaemia (Group 1: 1.56 (1.39-1.80) vs. Group 2: 1.53 (1.30-1.98) V, P = 0.99) and minimum microvascular resistance which normalizes the hyperaemia data for blood pressure (Group 1: 52.0 (43.2-67.4) vs. Group 2: 56.0 (43.7-69.6) mmHg/V, P = 0.70) did not differ in the two groups. Significant positive associations occurred between minimum microvascular resistance and indices of the insulin resistance syndrome; plasminogen activator inhibitor type 1 (R(s) = 0.46, P = 0.003), t-PA (R(s) = 0.36, P = 0.03), total cholesterol (R(s) = 0.35, P = 0.02), and triglyceride concentration (R(s) = 0.35, P = 0.02), and an inverse association with insulin sensitivity (R(s) = -0.33, P = 0.03).

CONCLUSIONS

In normoglycaemic adults cutaneous microvascular vasodilatory capacity is associated with features of insulin resistance syndrome, particularly with plasminogen activator inhibitor type 1. A strong family history of Type 2 diabetes alone does not result in impairment in the maximum hyperaemic response. Diabet. Med. 18, 541-545 (2001)

Fibrin D-dimer and coronary heart disease: prospective study and meta-analysis

BACKGROUND

It is unknown whether modest increases of fibrin D-dimer, a circulating marker of fibrin turnover, are relevant to coronary heart disease (CHD) in the general population.

METHODS AND RESULTS

We measured serum concentrations of D-dimer antigen in the stored baseline blood samples of 630 CHD cases and 1269 controls "nested" in a prospective cohort of 5661 men who were monitored for 16 years, and we conducted a meta-analysis of previous relevant studies to place our findings in context. In a comparison of men in the top third compared with those in the bottom third of baseline fibrin D-dimer values (tertile cutoffs, >94 versus <49 ng/mL), the odds ratio for CHD was 1.67 (95% CI, 1.31 to 2.13; P<0.0001) after adjustments for age and town. The odds ratio increased slightly after further adjustment for smoking, other classic risk factors, and indicators of socioeconomic status (1.79; 95% CI, 1.36 to 2.36). Strong correlations were observed of fibrin D-dimer values with circulating concentrations of C-reactive protein and serum amyloid A protein but not with smoking, blood lipids, blood pressure, and other risk factors.

CONCLUSION

Although there may be an association between circulating D-dimer values and CHD, further studies are needed to determine the extent to which this is causal.

Cardiovascular risk factors, including thrombotic variables, in a population with rheumatoid arthritis

OBJECTIVE

To compare prevalent cardiovascular disease, conventional cardiovascular risk factors and thrombotic variables in a cohort with well-controlled rheumatoid arthritis (RA) and in population controls.

METHODS

Seventy-six RA patients and 641 controls, randomly sampled from the local population in the North Glasgow MONICA study. Conventional cardiovascular risk factors (blood pressure, smoking, cholesterol) and thrombotic variables [fibrinogen, von Willebrand factor (vWF), tissue plasminogen activator antigen (t-PA), fibrin D-dimer, plasminogen activator inhibitor (PAI-1), plasma viscosity] were measured by standard procedures.

RESULTS

RA patients had a significantly higher prevalence of angina pectoris (P=0.03). Stroke also tended to be more common in the RA group, but the difference did not reach statistical significance (P=0.08). Diastolic blood pressure was significantly higher and serum cholesterol significantly lower in the RA group than in controls. Current smoking habits and exercise history were similar in the two groups, although RA patients were more likely to have previously smoked. Significant elevations in several thrombotic predictors of cardiovascular disease (fibrinogen, vWF, t-PA antigen and fibrin D-dimer) were found in the RA group.

CONCLUSIONS

In this RA patient population, diastolic blood pressure was higher than in controls and thrombotic variables were elevated compared with controls. These features are identified as potential additional cardiovascular risk factors in the RA patients studied. Prospective studies of risk modification may permit the identification of factors which could lead to a reduction in the known increased cardiovascular risk in RA.

C-reactive protein, fibrin D-dimer, and incident ischemic heart disease in the Speedwell study: are inflammation and fibrin turnover linked in pathogenesis?

Plasma levels of C-reactive protein (CRP, a marker of the reactant plasma protein component of the inflammatory response) and of fibrin D-dimer (a marker of cross-linked fibrin turnover) have each been associated in recent studies with the risk of future ischemic heart disease (IHD). Previous experimental studies have shown that fibrin degradation products, including D-dimer, have effects on inflammatory processes and acute-phase protein responses. In the Speedwell Prospective Study, we therefore measured CRP and D-dimer levels in stored plasma samples from 1690 men aged 49 to 67 years who were followed-up for incident IHD for an average of 75+/-4 months (mean+/-SD) and studied their associations with each other, with baseline and incident IHD, and with IHD risk factors. CRP and D-dimer levels were each associated with age, plasma fibrinogen, smoking habit, and baseline evidence of IHD. CRP was associated with D-dimer (r=0.21, P<0.00001). On univariate analyses, both CRP and D-dimer were associated with incident IHD. The incidence of IHD increased with CRP independently of the level of D-dimer (P=0.0002) and also increased with D-dimer independently of the level of CRP (P=0.048). In multivariate analyses, inclusion of D-dimer and conventional risk factors reduced the strength of the association between CRP and incident IHD; likewise, inclusion of CRP and conventional risk factors reduced the strength of the association between D-dimer and incident IHD. We conclude that although these respective markers of inflammation and fibrin turnover show modest association with each other in middle-aged men, they may have additive associations with risk of incident IHD. Further larger studies are required to test this hypothesis.

Combined prednisolone and intravenous immunoglobulin treatment for acquired factor VIII inhibitors: a 2-year review

Acquired inhibitors to factor VIII (FVIII) are rare, but life-threatening in up to 22% of cases. The optimal therapy for suppression of these inhibitors remains unclear. Prednisolone is the mainstay of therapy, producing responses in approximately 30% of cases. Intravenous immunoglobulin (IVIg) has a similar response rate, but a more rapid effect. We report the results of prednisolone 1 mg kg(-1) combined with IVIg 2 g kg(-1) in divided doses as first-line therapy in seven consecutive patients with acquired FVIII inhibitors. All patients were bleeding at the time of diagnosis with prolonged activated partial thromboplastin time. There were four complete responses, one partial response, one nonresponse and one with an inadequate follow-up for assessment of response, giving an overall response rate of 71%. In all complete responders the inhibitor declined rapidly and was undetectable by day 21 from start of treatment. Therapy was well tolerated and responses have been maintained off treatment for 2-8 months. This is a safe, well-tolerated rapidly acting regimen with good response rates.

The effects of transdermal estradiol in combination with oral norethisterone on lipoproteins, coagulation, and endothelial markers in postmenopausal women with type 2 diabetes: a randomized, placebo-controlled study

People with type 2 diabetes have a substantially increased risk of coronary heart disease (CHD). Short-term studies with unopposed oral estradiol in women with diabetes have suggested potentially beneficial effects on lipids, thrombotic factors, and insulin sensitivity. However, most (nonhysterectomized) postmenopausal women require combined estrogen-progesterone preparations. We randomized 43 women with type 2 diabetes either to continuous transdermal estradiol (80-microg patches) in combination with oral norethisterone (1 mg daily) or to identical placebos. Blood samples were taken before and after 6 months for measurement of lipoproteins, coagulation factors, and endothelial markers. Total cholesterol and triglyceride concentrations decreased by 8% and 22%, respectively, in those receiving hormone replacement therapy (P < 0.05 relative to change in placebo group after adjustment for baseline concentrations). There was a trend toward a reduction in high density lipoprotein cholesterol concentration (P = 0.06). Factor VII activity decreased by 16% (P < 0.001), and von Willebrand factor antigen decreased by 7% (P = 0.014) with active treatment. Levels of fibrinogen, tissue plasminogen activator, fibrin D dimer, very low density lipoprotein cholesterol, low density lipoprotein cholesterol, lipoprotein(a), and leptin were not significantly altered. No change in glycemic control was detected. Overall, lipid changes may be considered slightly beneficial with respect to CHD risk. The significant decrease in factor VII activity in this study is notable, because elevated factor VII activity has been associated with an increased risk of coronary thrombosis and normally increases with administration of oral estrogen-containing preparations. In addition, a reduction in von Willebrand factor antigen is consistent with an improvement in endothelial function. We suggest that the regimen used in this study may have the potential to reduce CHD risk in women with type 2 diabetes.

Haemostatic factors and risk of varicose veins and chronic venous insufficiency: Edinburgh Vein Study

Despite much research, the aetiology of venous disease is still poorly understood. Since haemostatic factors are involved in the processes of fibrinolysis and platelet aggregation, it is conceivable that such processes may be implicated in the pathology of varicose veins and chronic venous insufficiency (CVI). The Edinburgh Vein Study examined 1566 men and women aged 18-64 years that were randomly selected from the lists of 12 general practitioners. Each subject completed a questionnaire, underwent a comprehensive clinical examination and had a blood sample taken for the analysis of plasma fibrinogen, tissue plasminogen activator (t-PA) and von Willebrand factor (vWF) antigens. Subjects with trunk varicose veins and those with CVI had higher levels of each haemostatic factor compared with those with no trunk varices and no CVI. Although unit increases in t-PA and vWF were initially associated with a significantly increased risk of CVI in men, and both factors with an elevated risk of trunk varices in women, multiple adjustment for age, smoking status and body mass index reduced the odds ratios to non-significance. However, this does not entirely rule out the possibility of a pathogenic role for haemostatic factors in venous disease, but rather indicates the need for further experimental and epidemiological studies.

Lipoprotein-associated phospholipase A2 as an independent predictor of coronary heart disease. West of Scotland Coronary Prevention Study Group

BACKGROUND

Chronic inflammation is believed to increase the risk of coronary events by making atherosclerotic plaques in coronary vessels prone to rupture. We examined blood constituents potentially affected by inflammation as predictors of risk in men with hypercholesterolemia who were enrolled in the West of Scotland Coronary Prevention Study, a trial that evaluated the value of pravastatin in the prevention of coronary events.

METHODS

A total of 580 men who had had a coronary event (nonfatal myocardial infarction, death from coronary heart disease, or a revascularization procedure) were each matched for age and smoking status with 2 control subjects (total, 1160) from the same cohort who had not had a coronary event. Lipoprotein-associated phospholipase A2, C-reactive protein, and fibrinogen levels, and the white-cell count were measured at base line, along with other traditional risk factors. The association of these variables with the risk of coronary events was tested in regression models and by dividing the range of values according to quintiles.

RESULTS

Levels of C-reactive protein, the white-cell count, and fibrinogen levels were strong predictors of the risk of coronary events; the risk in the highest quintile of the study cohort for each variable was approximately twice that in the lowest quintile. However, the association of these variables with risk was markedly attenuated when age, systolic blood pressure, and lipoprotein levels were included in multivariate models. Levels of lipoprotein-associated phospholipase A2 (platelet-activating factor acetylhydrolase), the expression of which is regulated by mediators of inflammation, had a strong, positive association with risk that was not confounded by other factors. It was associated with almost a doubling of the risk in the highest quintile as compared with the lowest quintile.

CONCLUSIONS

Inflammatory markers are predictors of the risk of coronary events, but their predictive ability is attenuated by associations with other coronary risk factors. Elevated levels of lipoprotein-associated phospholipase A2 appear to be a strong risk factor for coronary heart disease, a finding that has implications for atherogenesis and the assessment of risk.

Tissue plasminogen activator and leucocyte elastase as predictors of cardiovascular events in subjects with angina pectoris: Edinburgh Artery Study

AIMS

To evaluate the relationship between haemostatic and rheological factors and cardiovascular outcome in subjects with angina pectoris in the general population.

METHODS AND RESULTS

Two hundred and seven men and women aged 55-74 had evidence of angina at baseline. Sixty-seven (32.3%) had a fatal or non-fatal cardiovascular event during follow-up. Median levels of tissue plasminogen activator antigen and leucocyte elastase were higher in the event group compared with the no event group (10.0 ng. ml(-1)vs 7.2 ng. ml(-1);P</=0.001, and 40.3 ng. ml(-1)vs 31.0 ng. ml(-1);P</=0.01, respectively). Whole blood viscosity was also significantly higher in the event group than in the no event group (3.80 mPa.s vs 3.53 mPa.s;P</=0.05). After adjusting for age and sex, unit increases in both tissue plasminogen activator antigen and leucocyte elastase levels were significantly associated with an increased risk of a cardiovascular event. These associations remained after further adjusting for cardiovascular risk factors and baseline myocardial infarction. The relative risks were 2.07 (95% CI, 1.30-3.45;P</=0.01) for tissue plasminogen activator antigen and 1. 95 (95% CI, 1.12-3.50;P</=0.05) for leucocyte elastase.

CONCLUSION

Disturbed fibrinolysis and activation of leucocytes may be implicated in the development of thrombotic cardiovascular events in subjects with angina pectoris in the general population.

Haemophilia care in central Scotland 1980-94. I. Demographic characteristics, hospital admissions and causes of death

To estimate the resources required to manage patients with haemophilia in Scotland, we studied the demographic features, hospital admissions and causes of deaths for individuals with haemophilia A and B and von Willebrand disease, treated with blood products, during the period 1980-94 living in central Scotland. Data were obtained from 413 adults and children (93% ascertainment). The age distribution in 1980 revealed a paucity of individuals over 60 years but the number in this age group increased over the study period. Of those with haemophilia A and B, 63 and two respectively, became HIV positive. Hospital admissions rose from 103 to 168 per annum; the number of annual bed days utilized also increased, but there was marked annual fluctuation (790-1832). The rate of admission was greater for those with severe haemophilia A and this increased during the 15-year period mainly due to the clinical consequences of human immunodeficiency virus (HIV) and hepatitis C virus (HCV). The admission rate for haemophilia B was significantly lower than that for haemophilia A, and was similar for all degrees of severity of the disorder. Throughout the 15-year period the incidence of admissions for acute bleeds was constant, as was the average duration in hospital. For those with a factor VIII inhibitor, the rate of admission was about double the rate of those without an inhibitor, although the duration of hospital stay was similar for both groups. There were 61 deaths; the death rate increased during the study period principally due to HIV and HCV, and 12 patients died from haemorrhage. We conclude that: (i) the life expectancy for haemophiliacs in Scotland was generally increasing, although HIV and HCV caused increasing mortality and morbidity (as shown by the increase in hospital admissions); (ii) hospital bed usage for the treatment of acute bleeds continued to be required, but fluctuated greatly; and (iii) the clinical impression that haemophilia B is less clinically severe than haemophilia A is confirmed by objective data. The planning implications for haemophilia care in Scotland and similar countries are discussed.

Femoral atherosclerosis in an older British population: prevalence and risk factors

Most estimates of the prevalence of peripheral atherosclerosis have been based on intermittent claudication or lower limb blood flow. The aim of this study was therefore to determine the prevalence of underlying femoral plaque, and to determine its association with other cardiovascular disease and risk factors. Presence of plaque was identified using ultrasound in a random sample of men (n=417) and women (n=367) aged 56-77 years. Coexistent cardiovascular disease, exercise and smoking were determined by questionnaire, blood pressure was recorded, and serum cholesterol and plasma fibrinogen were determined. Of the 784 subjects that were scanned, 502 (64%) demonstrated atherosclerotic plaque. Disease prevalence increased significantly with age (P<0.0001), and was more common in men (67.1 vs. 59.4%, P<0.05). Subjects with femoral plaque had a significantly greater odds of previous ischaemic heart disease (OR 2. 2, 95% CI 1.3, 3.7) and angina (OR 1.7, 95% CI 1.03, 2.7), but not of stroke or leg pain on exercise. Current and ex-smoking, raised serum total cholesterol and plasma fibrinogen levels, but not blood pressure, were associated with an increased risk of femoral plaque, independent of age and sex. Frequent exercise and a high HDL cholesterol were significantly associated with lower risk. In conclusion, therefore, atherosclerotic disease of the femoral artery affects almost two-thirds of the population in late middle age. It is associated with an increased prevalence of ischaemic heart disease and angina, but whether detecting at risk individuals using ultrasound offers advantages over simpler and less expensive risk factor scoring requires evaluation in trials.

Immunoradiometric assay of circulating C-reactive protein: age-related values in the adult general population

BACKGROUND

: Increased values of C-reactive protein (CRP), the classical acute phase protein, within the range below 5 mg/L, previously considered to be within the reference interval, are strongly associated with increased risk of atherothrombotic events, and are clinically significant in osteoarthritis and neonatal infection.

METHODS

: A robust new polyclonal-monoclonal solid- phase IRMA for CRP was developed, with a range of 0.05-10.0 mg/L.

RESULTS

: Plasma CRP values in general adult populations from Augsburg, Germany (2291 males and 2203 females; ages, 25-74 years) and Glasgow, Scotland (604 males and 650 females; ages, 25-64 years) were very similar. The median CRP approximately doubled with age, from approximately 1 mg/L in the youngest decade to approximately 2 mg/L in the oldest, and tended to be higher in females.

CONCLUSION

: This extensive data set, the largest such study of CRP, provides valuable reference information for future clinical and epidemiological investigations.

Effects of weaning age and diet on growth and carcass characteristics in steers

Two experiments were conducted to determine the effects of diet on growth of steers weaned at approximately 100 vs 205 d of age. In Exp. 1, a 2 x 2 x 2 factorial experiment was conducted using 78 Angus crossbred cow-calf pairs. The factors examined were age at weaning (early, at 103+/-3 d [EW] vs normal, at 203+/-3 d [NW]), feeding strategy (ad libitum vs postweaning programmed intake), and dietary CP concentration (100 vs 120% of NRC [1984] recommended levels). Early-weaned calves had a greater (P < .001) ADG than NW calves from 103 to 203 d and reached market weight at 385 d vs 418 d for NW calves (P < .001). Likewise, steers offered feed for ad libitum consumption reached market weight at 394 d, compared with 409 d for programmed-intake steers (P < .05). In Exp. 2, 64 Angus crossbred steers were either weaned at 93+/-3 d and fed one of four diets, weaned at 210+/-3 d without access to creep feed, or weaned at 210+/-3 d with access to creep feed for 60 d prior to weaning. Early-weaned calves were heavier (P < .01) than NW calves at 210 d if fed either 100 or 90% concentrate diets, and they had greater (P < .001) backfat thickness at 210 d but no difference (P > .10) in longissimus muscle area compared to EW calves fed a 60% concentrate diet. At slaughter, 80 to 100% of steers on all treatments graded low Choice or higher. Feeding high-concentrate diets to EW beef calves accelerated growth rate and fat deposition early in the feeding period and may be a way to provide young cattle for a high-quality beef market.

Methylene tetrahydrofolate reductase (MTHFR) and nitric oxide synthase (ecNOS) genes and risks of peripheral arterial disease and coronary heart disease: Edinburgh Artery Study

Hyperhomocysteinaemia and reduced nitric oxide synthesis may each result in endothelial dysfunction predisposing to atherogenesis. Genetic variants of methylene tetrahydrofolate reductase (MTHFR) and endothelial nitric oxide synthase (ecNOS) influence homocysteine metabolism and nitric oxide synthesis, respectively and might thus be determinants of the risk of atherosclerotic disease. The aim of our study was to identify, in a general population sample, the risks of peripheral arterial disease and of coronary heart disease related to MTHFR (175;198) and ecNOS (4;5) polymorphisms. In the Edinburgh Artery Study, which is a population based cohort study, 940 men and women aged 60-79 years, who had previously been selected at random from the general population, had DNA extracted from a venous blood sample. Based on a clinical examination at baseline and follow up investigations, three groups of subjects were identified: those with peripheral arterial disease (n=80), those with coronary heart disease (n=137), and healthy controls who had no evidence of cardiovascular disease (n=300). The distributions of the ecNOS and MTHFR genotypes did not differ significantly between the groups with and without cardiovascular disease. However, the ecNOS-4 allele (frequency 0.13) was related to the occurrence of coronary heart disease in non smokers, OR=2.47 (95% CI [1.42, 4.34], P=0.02). No association was found with peripheral arterial disease. The MTHFR-175 allele (frequency 0.31) was not related to coronary heart disease, but was associated with a reduced risk of peripheral arterial disease, OR=0.54 (95% CI [0.32, 0.90], P=0.02). Neither the ecNOS-4 allele or MTHFR-175 allele was related to the ankle brachial pressure index in the whole study population. In conclusion, the ecNOS-4 allele was associated with a slightly increased risk of coronary heart disease in non-smokers, but otherwise the MTHFR and ecNOS genotypes appeared to have little influence on the risks of peripheral arterial disease and coronary heart disease in this older population.