Diabetes mellitus and cardiovascular disease in women

Cardiovascular disease in African American women: a health care disparities issue

OBJECTIVES

To review the current status of cardiovascular disease (CVD) in African American women compared to Caucasian women in regards to 4 categories of CVD: coronary artery disease (CAD), hypertension, stroke, and congestive heart failure (CHF), and to call attention to the need to place more emphasis on the need to increase awareness of CVD as the greatest killer of African American females in the United States.

METHODS

A review of the recent literature on the subject of CVD in women over the past several years was conducted with a focus on CVD in African American women. Statistical data on incidence, prevalence, morbidity and mortality of CAD, hypertension, stroke, and CHF in black and white women were compared.

RESULTS

Statistical data gathered over the past several years indicate that African American women have greater mortality than Caucasian women from CAD, hypertension, stroke, and CHF. The mortality rate from CAD is 69% higher in black women than in white women. Mortality for black females from hypertension is 352% higher than for white females. Age-adjusted stroke death rates are 54% higher in African American than in Caucasian women, and the age-adjusted mortality rate per 100,000 is 113.4 vs. 97.5 for black and white women, respectively. Incidence, prevalence, and morbidity figures for CAD, hypertension, stroke, and CHF are all higher for African American females than for Caucasian females.

CONCLUSIONS

African American women are at exceptional risk for CVD, and more recognition of this fact as well as greater awareness of the problem should be promulgated and distributed by means of public education programs. Physicians who treat black patients also need to be encouraged to be more aggressive in their efforts to detect patients at risk and to initiate therapy early on in the course of CVD in this sub-population.

Implementation of the fit body and soul, a church-based life style program for diabetes prevention in high-risk African Americans: a feasibility study

PURPOSE

The purpose of this study was to determine the effects of a behavioral faith-based diabetes prevention program called the Fit Body and Soul program in a semi-urban African-American church using a community-based participatory approach.

METHODS

The 12-session Fit Body and Soul program was modified from the group lifestyle balance intervention that was modified from the successful National Institute of Health (NIH) funded Diabetes Prevention Program. The Fit Body and Soul program was implemented in a semi-urban African-American church community. Based on the results of physical examinations and increased body mass index (BMI > or = 25), 40 adult members of the church were identified as being at high risk for diabetes. Four church ministers, after receiving Fit Body and Soul program training for 2 days, served as study interventionists. The primary objective was weight loss of at least 5% by the end of the 12-session Fit Body and Soul intervention.

RESULTS

Screening of church participants was conducted at the Gospel Water Branch Baptist Church in Augusta, Georgia. A total of 40 individuals having a BMI > or = 25 were selected. Of the 40, a total of 35 (87.5%) attended at least 10 sessions and provided information required for the study. Of the 35, a total of 48% lost at least 5% of baseline weight, 26% lost 7% or more, and 14% lost >10% of baseline weight.

CONCLUSIONS

This pilot trial suggests that carrying out a larger Fit Body and Soul study in a faith-based setting, using behavioral lifestyle interventions, in the context of a diabetes prevention program for African American communities is feasible, as is the possibility that subjects in that larger study will achieve a clinically significant degree of weight loss.

Cardiovascular disease in women

Cardiovascular disease (CVD) remains the most important health issue facing women and continues to be their number one cause of morbidity and mortality. Women are disproportionately affected by CVD compared with men. It is diagnosed less often and treated less aggressively in the inpatient and outpatient settings; as a result, women have poorer outcomes. It is therefore imperative that physicians take steps to screen women for the risks associated with CVD and actively education them on primary and secondary prevention.

The nitroxide tempol has similar antioxidant effects as physiological levels of 17beta-oestradiol in reversing ovariectomy-induced oxidative stress in mice liver and kidney

OBJECTIVE

Oestrogen defciency increases oxidative stress postmenopause, while tempol is an intracellular radical scavenger that interferes with the formation or effects of many radicals. We aimed to investigate the effects of oestrogen and tempol on oxidative stress parameters in the kidney and liver of ovariectomized mice.

MATERIAL AND METHODS

Forty 8-week-old female Bald/c mice were divided into five groups: sham-operated, ovariectomized mice without treatment, ovariectomized mice treated with tempol, ovariectomized mice treated with 17beta-oestradiol and ovariectomized mice treated with 17beta-oestradiol and tempol. Oxidative stress in liver and kidney tissues was investigated by measuring 2-thiobarbituric acid reactive substances (TBA-RS), reduced glutathione, myeloperoxidase, superoxide dismutase and catalase levels.

RESULTS

TBA-RS levels were increased and reduced glutathione, myeloperoxidase, superoxide dismutase levels were decreased in the tissues of ovariectomized mice. This effect of ovariectomy on oxidative stress parameters was opposed significantly by the administration of tempol and 17beta-oestradiol either alone or in combination. Ovariectomy reduced the kidney catalase levels, but the effect was not statistically significant (p>0.05). On the other hand, catalase levels were elevated significantly in all treatment groups compared to those of the ovariectomized group (p<0.05).

CONCLUSION

These study findings demonstrate that tempol significantly opposes the oxidative stress generated by ovariectomy. This effect, which is evident in remote tissues such as liver and kidney, is comparable to that of physiological levels of oestradiol.

Sex differences in the incidence of hemorrhagic and ischemic stroke among diabetics in Taiwan

BACKGROUND

Diabetes mellitus is an important risk factor for stroke, but whether there is differential gender-specific risk has not been fully elucidated. We aimed to explore the impact of gender on incidence and relative risks of hemorrhagic and ischemic stroke among the diabetic population in Taiwan.

METHODS

In this study, 500,868 diabetic patients and 500,248 age matched and-sex-matched nondiabetic individuals were linked to inpatient claims (1997-2002) to identify hospitalizations for nontraumatic hemorrhagic and ischemic stroke. Incidence density was calculated with the Poisson assumption, and Kaplan-Meier analysis was used to assess the cumulative incidence over a 6-year follow-up period. We also evaluated the relative hazards of stroke in relation to diabetes with the Cox proportional hazard model, adjusted with demographics and geographic regions.

RESULTS

The incidence of hemorrhagic stroke in diabetic women was less than that in diabetic men except in those aged > or =85, but the difference between male and female diabetic patients was less pronounced with ischemic stroke. The hazard ratios (HRs) of hemorrhagic and ischemic stroke among diabetic women were increased by a magnitude of 1.2 and 1.32, respectively, which were significantly higher than those of diabetic men. Further age-stratified analysis indicated that young and middle-aged diabetic women tended to have higher HRs and that diabetic women aged <35 suffered from particularly high HRs (HR 7.69, 95% confidence interval [CI] 1.81-32.75 for hemorrhagic stroke, and HR = 8.46, 95% CI 4.28-16.75 for ischemic stroke).

CONCLUSIONS

There was a significant gender-diabetes interactive effect on the incidence of hemorrhagic and ischemic stroke. Additionally, young Taiwanese diabetic patients were most vulnerable to an increased relative risk of hemorrhagic and ischemic stroke. Comprehensive diabetic care with stroke prevention measures should be emphasized in young diabetic people in order to prevent premature disability.

F(2)-isoprostanes as novel biomarkers for type 2 diabetes: a review

Oxidative stress (OS) has been implicated as one of the major underlying mechanisms behind many acute and chronic diseases. However, the measurement of free radicals or their end products is complicated. Isoprostanes, derived from the non-enzymatic peroxidation of arachidonic acid are now considered to be reliable biomarkers of oxidant stress in the human body. Isoprostanes are involved in many of the human diseases such as type 2 diabetes. In type 2 diabetes elevated levels of F₂-Isoprostanes (F₂-IsoPs) have been observed. The measurement of bioactive F₂-IsoPs levels offers a unique noninvasive analytical tool to study the role of free radicals in physiology, oxidative stress-related diseases, and acute or chronic inflammatory conditions. Measurement of oxidative stress by various other methods lacks specificity and sensitivity. This review aims to shed light on the implemention of F₂-IsoPs measurement as a gold-standard biomarker of oxidative stress in type 2 diabetics.

Cardiac health in women with metabolic syndrome: clinical aspects and pathophysiology

Although the classical cardiovascular risk factors (e.g., smoking and hypertension) are becoming more effectively managed, a continuous increase of the so-called "cardiometabolic risk" is noted. Starting from this century, the nomenclature "metabolic syndrome" has become more popular to identify a cluster of disorders including obesity, dyslipidemia, hypertension, and insulin resistance. It is a primary risk factor for diabetes and cardiovascular disease in both genders. Interestingly, the metabolic diseases display a distinct gender disparity with an apparent "female advantage" in the premenopausal women compared with age-matched men. However, women usually lose such "sex protection" following menopause or affliction of metabolic syndrome especially insulin resistance. A controversy exists in the medical literature concerning whether metabolic syndrome is a real syndrome or simply a cluster of risk factors. Several scenarios are speculated to contribute to the gender dimorphism in the cardiovascular sequelae in patients with metabolic syndrome including sex hormones, intrinsic organ function, and the risk factor profile (e.g., hypertension, dyslipidemia, obesity, sedentary lifestyle, and atherogenic diet). With the alarming rise of obesity prevalence, heart problems in metabolic syndrome continue to rise with a distinct gender dimorphism. Although female hearts seem to better tolerate the stress insults compared with the male counterparts, the female sex hormones such as estrogen can interact with certain risk factors to precipitate myopathic changes in the hearts. This synthetic review of recent literature suggests a role of gender disparity in myopathic factors and risk attributable to each metabolic component in the different prevalence of metabolic syndrome.

Menopause modulates homocysteine levels in diabetic and non-diabetic women

High total homocysteine (tHcy) plasma levels may contribute to the increased cardiovascular risk of Type 2 diabetic women. However, to date, data on factors modulating tHcy concentration in this population are scarce. Fasting tHcy, vitamin B12, folate plasma levels, and the methylene tetrahydrofolate reductase (MTHFR) C677T genotype as well as clinical, biochemical, and lifestyle variables were compared in 91 Type 2 diabetic and 91 matched non-diabetic women (40 pre- and 51 post-menopausal, in each group). Fasting tHcy concentration did not differ between diabetic and control women, even after multivariable adjustment. In both groups, tHcy levels increased after menopause, but the differences were weakened after multivariable adjustment. The MTHFR genotype distribution was in accordance with the Hardy-Weinberg equilibrium, with a similar TT frequency in diabetic (22.2 %) and control women (19.8%). Overall, tHcy plasma concentration was higher in TT homozygous compared to other genotypes. We found a menopause-genotype interaction on tHcy levels (p=0.068 for menopause*genotype interaction); overall, the increase of tHcy concentration in TT subjects was limited to pre-menopause (p<0.0001; adjusted p=0.024), and this was confirmed after considering diabetic and control women separately (p=0.001 and p=0.01, respectively). At multivariate analysis, menopause was an independent correlate of tHcy concentration, together with creatinine, folate and MTHFR genotype. Our data show that menopause has a strong influence on tHcy concentration even in Type 2 diabetic women and demonstrate, for the first time, that it may modulate the association between tHcy and the common MTHFR polymorphism both in diabetic and non-diabetic women.

Severity of coronary artery disease in postmenopausal diabetic women

OBJECTIVE

Coronary artery disease (CAD) risk increases in women after the menopause. The aim of this study was to determine the effect of diabetes on the severity of CAD in postmenopausal women undergoing coronary angiography.

DESIGN

180 postmenopausal women underwent coronary angiography for suspected CAD. CAD severity was assessed by the number of arteries (0-3) with >50% stenosis in the angiography. Forty-four women had type 2 diabetes mellitus (T2DM). Predisposing risk factors and biochemical and hormonal parameters were recorded. The diabetic women were older (p=0.014), had higher BMI and waist circumference (p<0.001), higher prevalence of hypertension (p=0.002), higher levels of triglycerides, uric acid and higher HOMA-Insulin Resistance Index (p=0.009).

RESULTS

The women with diabetes had a higher prevalence of severe stenosis in the angiography: T2DM: 0-vessels 25%, 1-vessel disease 18.2%, 2-vessels disease 22.7%, 3-vessels disease 34.1%, vs. 49.2%, 23.5%, 22.1%, 5.1% in the non-diabetic women, respectively (p<0.001). Binary logistic regression analysis showed that T2DM was a significant predictor of severe CAD (>or=3 vessel disease) independently of age, family history of T2DM, BMI, time since menopause, hypertension and hypercholesterolemia. Women with T2DM also had lower sex hormone binding globulin (SHBG, p=0.010) levels compared to non-diabetic women.

CONCLUSIONS

Diabetic postmenopausal women develop more severe CAD compared to non-diabetic women. This association is independent of other predisposing factors and suggests an independent effect of T2DM on the atherosclerotic process, at least in women after menopause.

Age and gender differences in the impact of diabetes on the prevalence of ischemic heart disease: a population-based register study

OBJECTIVE

To explore age and gender differences in the impact of diabetes on the prevalence of ischemic heart disease (IHD) in a defined population.

METHODS

Data were obtained from an administrative health care register covering a population of about 415,000. The study included all patients aged 45-74 years diagnosed between 1999 and 2003 with IHD (n=11,311) and diabetes (n=10,364) by physicians at all primary health care centres (PHCs) and out- and inpatient clinics at all hospitals in the county of Ostergötland, Sweden.

RESULTS

In the 45-54-year-old age group, diabetes was associated with an increase in IHD prevalence equivalent to ageing about 20 years in women and 10 years in men. The diabetes/nondiabetes IHD prevalence rate ratio (IPR) decreased with age in both men and women (trend p-values <0.001). The IPR was higher among women than men in each age group, though the female relative excess decreased from 75% higher in the 45-54-year-old age group to 33% higher in the 65-74-year-old age group (trend p-value=0.018).

CONCLUSIONS

The relative gender difference in the impact of diabetes on IHD in younger middle-aged patients remained up to the age of 65 years, decreasing considerably thereafter.

Review: Aspirin and Diabetes Mellitus: revisiting an old player

Type 2 Diabetes Mellitus confers an excess risk of cardiovascular disease. The mechanisms involved in the development of the disease are an active field of research, and prompt the development of newer and safer therapeutics with implications for cardiovascular disease. Currently there is increasing awareness of the role of platelet dysfunction, low-grade chronic inflammation and thrombogenesis in the pathophysiology of insulin resistance, T2DM, as well as type 1 diabetes mellitus and cardiovascular disease. This new evolving knowledge has allowed a better understanding of the role of aspirin, an old medication with proven beneficial effects on patients with established cardiovascular disease. The influence of salicylates on insulin resistance, glucose homeostasis, platelet function and inflammatory pathways, in particular related to the activation of the NF κB pathway, is a promising field of active research, and will help in the management of both diabetes mellitus and atherosclerotic-related cardiovascular disease.

Role of exercise training in cardiovascular autonomic dysfunction and mortality in diabetic ovariectomized rats

Diabetes and menopause markedly increase the risk of cardiovascular disease in women. The objective of the present study was to investigate the effects of exercise training on cardiovascular autonomic dysfunction and on total mortality in diabetic female rats undergoing ovarian hormone deprivation. Female Wistar rats were divided into ovariectomized groups: sedentary and trained controls and sedentary and trained diabetic rats (streptozotocin, 50 mg/kg IV). Trained groups were submitted to an exercise training protocol on a treadmill (8 weeks). The baroreflex sensitivity was evaluated by heart rate responses to arterial pressure changes. Heart rate variability was determined using the SD of the basal heart rate. Vagal and sympathetic tonus were evaluated by pharmacological blockade. Diabetes impaired baroreflex sensitivity ( approximately 55%), vagal tonus ( approximately 68%), and heart rate variability ( approximately 38%). Exercise training improved baroreflex sensitivity and heart rate variability in control and diabetic groups in relation to their sedentary groups. Trained control rats presented increased vagal tonus compared with that of sedentary ones. The sympathetic tonus was reduced in the trained diabetic group as compared with that of other studied groups. Significant correlations were obtained between heart rate variability and vagal tonus with baroreflex sensitivity. Mortality, assessed during the training period, was reduced in trained diabetic (25%) rats compared with mortality in sedentary diabetic rats (60%). Together, these findings suggest that decreases in baroreflex sensitivity and heart rate variability may be related to increased mortality in female diabetic subjects and that improved autonomic regulation induced by exercise training may contribute to decreased mortality in this population.

The endothelium and vascular inflammation in diabetes

The endothelium releases multiple mediators, not only regulators of vasomotor function but also important physiological and pathophysiological inflammatory mediators. Endothelial dysfunction is caused by chronic exposure to various stressors such as oxidative stress and modified low-density lipoprotein (LDL) cholesterol, resulting in impaired nitric oxide (NO) production and chronic inflammation. Biomechanical forces on the endothelium, including low shear stress from disturbed blood flow and hypertension, are also important causes of endothelial dysfunction. These processes seem to be augmented in patients with diabetes. In states of insulin resistance and in type 2 diabetes insulin signalling is impaired. Increased vascular inflammation, including enhanced expression of interleukin- 6 (IL-6), vascular cellular adhesion molecule-1 (VCAM-1) and monocyte chemoattractant protein (MCP- 1) are observed, as is a marked decrease in NO bioavailability. Furthermore, hyperglycaemia leads to increased formation of advanced glycation end products (AGE), which quench NO and impair endothelial function. In summary, during the development of diabetes a number of biochemical and mechanical factors converge on the endothelium, resulting in endothelial dysfunction and vascular inflammation. In the presence of insulin resistance, these processes are potentiated and they provide a basis for the macrovascular disease seen in diabetes.

The role of paraoxonase (PON) enzyme in the extent and severity of the coronary artery disease in type-2 diabetic patients

Increased coronary artery disease (CAD) risk is well established in diabetes mellitus (DM). Paraoxonase (PON) enzyme is known to have protective effects on lipid peroxidation. This study aimed to investigate the changes in PON activity levels with duration of DM as well as the role of PON activity in progression of CAD. Eighty-four consecutive diabetic patients (mean age 58 years, 46 men) who underwent coronary angiography for diagnostic purposes were examined. Before the angiography, fasting venous blood samples were taken for PON enzyme activity, thiobarbituric acid reactive substances (TBARS), and routine biochemical parameters. Severity and extent of coronary atherosclerosis were scored numerically using the Gensini scoring system. The population was divided into three groups according to Gensini score: Group 1, mild CAD; Group 2, moderate CAD; Group 3, severe CAD. Group 1 had higher PON levels and shorter DM duration than those of Group 3. Gensini score was significantly correlated with, PON activity (r = -0.361) and apo-AI (r = -0.375). TBARS (r = -0.290) and the duration of DM (r = -0.336) also showed a significant correlation with PON activity levels. Also, multivariate linear regression and Pearson correlation analyses showed that PON activity (P = 0.04), apo-AI levels (P = 0.01), and the duration of DM (P = 0.003) were significantly associated with Gensini score. Paraoxonase activity decreases parallel to DM duration. The lack of protective effect of PON enzyme on lipid peroxidation may be a factor in acceleration of CAD in DM.

Hypersensitivity of myofilament response to Ca2+ in association with maladaptation of estrogen-deficient heart under diabetes complication

The amelioration of cardioprotective effect of estrogen in diabetes suggests potential interactive action of estrogen and insulin on myofilament activation. We compared Ca2+-dependent Mg2+-ATPase activity of isolated myofibrillar preparations from hearts of sham and 10-wk ovariectomized rats with or without simultaneous 8 wk-induction of diabetes and from diabetic-ovariectomized rats with estrogen and/or insulin supplementation. Similar magnitude of suppressed maximum myofibrillar ATPase activity was demonstrated in ovariectomized, diabetic, and diabetic-ovariectomized rat hearts. Such suppressed activity and the relative suppression in α-myosin heavy chain level in ovariectomy combined with diabetes could be completely restored by estrogen and insulin supplementation. Conversely, the myofilament Ca2+ hypersensitivity detected only in the ovariectomized but not diabetic group was also observed in diabetic-ovariectomized rats, which was restored upon estrogen supplementation. Binding kinetics of β1-adrenergic receptors and immunoblots of β1-adrenoceptors as well as heat shock 72 (HSP72) were analyzed to determine the association of changes in receptors and HSP72 to that of the myofilament response to Ca2+. The amount of β1-adrenoceptors significantly increased concomitant with Ca2+ hypersensitivity of the myofilament, without differences in the receptor binding affinity among the groups. In contrast, changes in HSP72 paralleled that of maximum myofibrillar ATPase activity. These results indicate that hypersensitivity of cardiac myofilament to Ca2+ is specifically induced in ovariectomized rats even under diabetes complication and that alterations in the expression of β1-adrenoceptors may, in part, play a mechanistic role underlying the cardioprotective effects of estrogen that act together with Ca2+ hypersensitivity of the myofilament in determining the gender difference in cardiac activation.

Diabetes and Hypertension: Epidemiology of the Relationship and Pathophysiology of Factors Associated With These Comorbid Conditions

Diabetes and hypertension frequently coexist, leading to additive increases in the risk of life-threatening cardiovascular events. Hypertension is a common comorbid condition in patients with type 1 or type 2 diabetes when compared with the general population and occurs in 75% of patients with the more prevalent form of diabetes, type 2. Arterial blood pressure plays an important role in the development of renal damage and presents a complex relationship. It is well-known that hypertension accelerates the course of microvascular and macrovascular complications of diabetes and that hypertension often precedes type 2 diabetes and vice versa. Patients with type 1 and 2 diabetes and nephropathy frequently have circadian changes in blood pressure that correlate to nephropathy risk. Early detection of nocturnal hypertension and early intervention with angiotensin blockade may delay progression of diabetic nephropathy.

Can a chronic care model collaborative reduce heart disease risk in patients with diabetes?

BACKGROUND

There is a need to identify effective practical interventions to decrease cardiovascular disease risk in patients with diabetes.

OBJECTIVE

We examine the impact of participation in a collaborative implementing the chronic care model (CCM) on the reduction of cardiovascular disease risk in patients with diabetes.

DESIGN

Controlled pre- and postintervention study.

PATIENTS/PARTICIPANTS

Persons with diabetes receiving care at 13 health care organizations exposed to the CCM collaborative and controls receiving care in nonexposed sites.

MEASUREMENTS AND MAIN RESULTS

Ten-year risk of cardiovascular disease; determined using a modified United Kingdom Prospective Diabetes Study risk engine score. A total number of 613 patients from CCM intervention sites and 557 patients from usual care control sites met the inclusion criteria. The baseline mean 10-year risk of cardiovascular disease was 31% for both the intervention group and the control group. Participants in both groups had improved blood pressure, lipid levels, and HbA1c levels during the observation period. Random intercept hierarchical regression models showed that the intervention group had a 2.1% (95% CI -3.7%, -0.5%) greater reduction in predicted risk for future cardiovascular events when compared to the control group. This would result in a reduced risk of one cardiovascular disease event for every 48 patients exposed to the intervention.

CONCLUSIONS

Over a 1-year interval, this collaborative intervention using the CCM lowered the cardiovascular disease risk factors of patients with diabetes who were cared for in the participating organization's settings. Further work could enhance the impact of this promising multifactorial intervention on cardiovascular disease risk reduction.

Effects of low-dose continuous combined hormone replacement therapy on glucose homeostasis and markers of cardiovascular risk in women with type 2 diabetes

BACKGROUND

Low-dose hormone replacement therapy (HRT) has attracted interest for the treatment of postmenopausal symptoms in diabetes because of concerns about increased risk of coronary heart disease (CHD) and stroke with conventional HRT containing conjugated equine oestrogens (CEEs) and medroxyprogesterone acetate (MPA).

OBJECTIVES

We assessed the effects on glucose homeostasis and cardiovascular risk factors of continuous oral 17beta oestradiol (1 mg) and norethisterone (0.5 mg) in postmenopausal women with type 2 diabetes.

DESIGN

Double-blind, randomized placebo-controlled trial.

ASSESSMENTS

Hyperinsulinaemic isoglycaemic clamp and cardiovascular risk factors were assessed before and after 3 months of treatment.

RESULTS

Twenty-eight women completed the study. HRT decreased fasting glucose compared with placebo [-9.4% with HRT vs.+2.3% for placebo, 95% confidence interval (CI) -23.2 to -0.3] and total cholesterol (-13.7 vs.+1.0%, 95% CI -22.4 to -3.1%) No significant effect was seen on metabolic clearance rate of glucose, glycated haemoglobin (HbA1c), triglycerides, high density lipoprotein (HDL)-cholesterol or C-reactive protein (CRP).

CONCLUSIONS

In women with type 2 diabetes, low-dose HRT decreased fasting glucose and total cholesterol without detectable adverse effects on glucose clearance, triglycerides and CRP as reported with conventional HRT.

Does diabetes mellitus explain the higher hospital mortality of women with acute myocardial infarction? Results from the Berlin Myocardial Infarction Registry

BACKGROUND

Women with acute myocardial infarction (AMI) exhibit greater hospital mortality than do men. In general, diabetes mellitus is one of the major factors influencing the outcome of patients with AMI. The aim of this study was to analyze the interaction between diabetes and gender, specifically with regard to the higher hospital mortality of female AMI patients aged < or = 75 years.

METHODS

We prospectively collected data from 3,715 patients aged < or = 75 (2,794 men, 921 women) with acute myocardial infarction who were treated in 25 hospitals in Berlin, Germany, from 1999 to 2002. In a multivariate analysis, we specifically studied the interaction between the factors diabetes mellitus and gender in their effects on hospital mortality.

RESULTS

After adjustment in multivariate analysis, the interaction between gender and diabetes was statistically significant, and the estimated odds ratios were as follows: female diabetic patients compared with male diabetic patients, odds ratio (OR) = 2.28 (95% confidence interval [CI] 1.42-3.68); female diabetic patients compared with male nondiabetic patients, OR = 2.90 (95% CI 1.90-4.42); and female diabetic patients compared with female nondiabetic patients, OR = 2.92 (95% CI 1.75-4.87). There was no statistically significant difference between the risk of dying for female nondiabetic patients or for male diabetic patients when compared with male nondiabetic patients.

CONCLUSIONS

In AMI patients aged < or = 75 years, female gender alone is not an independent predictor of hospital mortality. Detailed, multivariate analysis reveals that specifically diabetic women demonstrate higher hospital mortality than do men. Special attention should be provided to these female diabetic patients.

Endothelial dysfunction and its role in diabetic vascular disease

When normal endothelial function is shifted to a pathological degree, the foundation is laid for possibly following diseases. This endothelial dysfunction is characterized by a proinflammatory state, reduced vasodilation, and a prothrombotic state. In the continuation this dysfunction is strongly associated cardiovascular morbidity and mortality. Endothelial dysfunction is markedly enhanced in type 2 diabetes providing a major pathophysiological cause for the massively increased cardiovascular risk of diabetic patients. Subsequently future therapeutic approaches for the treatment of diabetic cardiovascular disease should target the dysfunctional endothelium first.

Antihypertensive Efficacy of Irbesartan/HCTZ in Men and Women With the Metabolic Syndrome and Type 2 Diabetes

This subgroup analysis of the Irbesartan/Hydrochlorothiazide (HCTZ) Blood Pressure Reductions in Diverse Patient Populations (INCLUSIVE) trial evaluated the efficacy and safety of irbesartan/HCTZ fixed combinations in adults with uncontrolled systolic blood pressure (SBP) (140-159 mm Hg; 130-159 mm Hg for type 2 diabetes mellitus [T2DM]) after >or=4 weeks of antihypertensive monotherapy. Treatment was sequential: placebo (4-5 weeks), HCTZ 12.5 mg (2 weeks), irbesartan/HCTZ 150/12.5 mg (8 weeks), and irbesartan/HCTZ 300/25 mg (8 weeks). In the intent-to-treat analysis, mean change from baseline (end of placebo phase) off all previous therapy to Week 18 (study end) in T2DM patients (n=227) was -18.2+/-14.1 mm Hg for SBP (primary end point; p<0.001) and -8.7+/-8.2 mm Hg for diastolic blood pressure (p<0.001). Mean SBP/diastolic blood pressure changes in patients with the metabolic syndrome (n=345) were -21.0+/-14.3/-10.4+/-8.5 mm Hg (p<0.001). Overall, 56% (95% confidence interval, 49%-62%) of T2DM and 73% (95% confidence interval, 68%-77%) of metabolic syndrome patients achieved SBP goal (<140 mm Hg; <130 mm Hg for T2DM). Goal attainment rates were significantly higher among women with the metabolic syndrome than men. Treatments appeared to be well tolerated. Irbesartan/HCTZ fixed combinations achieved SBP goals in over half of the T2DM patients and nearly three quarters of patients with the metabolic syndrome, with SBP uncontrolled on antihypertensive monotherapy.

Estrogen treatment improves arterial distensibility, fibrinolysis, and metabolic profile in postmenopausal women with type 2 diabetes mellitus

The effects of isolated estrogen therapy on the hemostatic system and arterial distensibility were determined in postmenopausal females with type 2 diabetes mellitus. This was a prospective nonrandomized study of 19 subjects (age, 56.2 +/- 4.7 years; body mass index, 27.8 +/- 2.4 kg/m(2) [mean +/- SD]). Inclusion was done after 2 months of glycemic and blood pressure control. The study consisted of 4 months of placebo treatment immediately followed by an equal period of oral conjugated equine estrogens (CEE) 0.625 mg/d. Measures included anthropometrics, a metabolic profile (oral glucose tolerance test and fasting glycated hemoglobin, total cholesterol and fractions, and triglyceride levels), and coagulation and fibrinolytic factors at the end of the placebo period and after 4 months of oral CEE. Conjugated equine estrogen therapy decreased plasminogen activator inhibitor 1 (placebo x CEE: 16.33 +/- 9.11 x 13.08 +/- 8.87 UI/mL, P < .03) and increased factor VIII activity (134.11% +/- 46.18% x 145.33% +/- 42.04%, P < .04). An increase in high-density lipoprotein cholesterol levels (placebo x CEE: 42.47 +/- 6.80 x 53.32 +/- 11.89 mg/dL, P < .01), and a decrease in glycated hemoglobin (8.45% +/- 1.30% vs 7.58% +/- 1.06%, P < .02) and in fasting glucose levels (121.51 +/- 21.05 x 111.21 +/- 20.74 mg/dL, P = .02) followed CEE therapy. Pulse wave velocity and augmentation index were performed by applanation tonometry and were obtained at the end of the placebo period (placebo), again after an intravenous load of 1.25 mg of CEE (short-term), and after 4 months of oral CEE (long-term). A significant decrease in central (carotid-femoral) pulse wave velocity was seen both after short- and long-term CEE (placebo vs short-term vs long-term: 9.36 +/- 2.58 vs 8.26 +/- 2.20 vs 7.98 +/- 1.90 m/s, respectively [analysis of variance, P < .03]; placebo vs short-term, P < .05; placebo vs long-term, P < .01), whereas augmentation index decreased only after long-term CEE (placebo vs short-term vs long-term: 39.14% +/- 6.94% vs 37.48% +/- 8.67% vs 34.3.3% +/- 8.11% [analysis of variance, P < .05], respectively; placebo vs long-term, P < .05). Long-term administration of CEE leads to an improvement in fibrinolysis and arterial distensibility, associated with an increase of the intrinsic coagulation pathway in postmenopausal women with type 2 diabetes mellitus.

High Cardiovascular Risk in Patients With Diabetes and the Cardiometabolic Syndrome: Mandate for Statin Therapy

Diabetes mellitus confers a high risk of cardiovascular morbidity and mortality and requires aggressive management of all cardiovascular risk factors, including diabetic dyslipidemia. Although levels of low-density lipoprotein cholesterol are often normal or only slightly elevated in persons with diabetes, lipid-altering therapy with statins has been shown in large, randomized, controlled trials to decrease the risk of cardiovascular complications in this patient population. A target low-density lipoprotein cholesterol level of <70 mg/dL is now a therapeutic option in patients at very high risk for coronary heart disease, including patients with diabetes. Diabetes is also a leading cause of end-stage renal disease. In addition to their lipid-modifying effects, statins have been shown to slow the progression of diabetic nephropathy and potentially exert other renoprotective effects; these benefits, however, remain to be confirmed in clinical trials.

Sex difference in cardiomyocyte function in normal and metallothionein transgenic mice: the effect of diabetes mellitus

Evidence suggests a sex difference in intrinsic physiological and diabetic myocardial contractile function related to antioxidant properties of female ovarian hormones. This study was designed to examine the effect of cardiac overexpression of antioxidant metallothionein on intrinsic and diabetic cardiomyocyte function. Weight-matched wild-type (FVB) and metallothionein transgenic mice of both sexes were made diabetic with streptozotocin (220 mg/kg). Contractile and intracellular Ca2+ properties were evaluated including peak shortening (PS), time to PS, time to 90% relengthening (TR90), maximal velocity of shortening or relengthening (±d L/d t), fura-2 fluorescence intensity change, and Ca2+ decay rate. Akt and transcription factor c-Jun levels were evaluated by Western blot. Myocytes from female FVB mice exhibited lower PS, ±d L/d t, and fura-2 fluorescence intensity change, prolonged time to PS, TR90, and Ca2+ decay compared with male FVB mice. Interestingly, this sex difference was not present in metallothionein mice. Diabetes depressed PS, ±d L/d t and caffeine-induced Ca2+ release, as well as prolonged TR90 and Ca2+ decay in male FVB mice, whereas it only reduced PS in female FVB mice. These diabetic dysfunctions were nullified by metallothionein in both sexes. Females displayed elevated Akt phosphorylation and reduced c-Jun phosphorylation. Diabetes dampened Akt phosphorylation in male FVB mice and enhanced c-Jun in both sexes. Diabetes-induced alterations in Akt phosphorylation and c-Jun were abolished by metallothionein. The sex difference in Akt phosphorylation but not c-Jun levels was reversed by metallothionein. These data indicate that antioxidant capacity plays an important role in sex differences in both intrinsic and diabetic cardiomyocyte contractile properties possibly related to phosphorylation of Akt and c-Jun.

Gender disparity of streptozotocin-induced intrinsic contractile dysfunction in murine ventricular myocytes: role of chronic activation of Akt

1. Clinical, epidemiological and experimental evidence suggests a 'female advantage' in the progression of cardiovascular diseases, including diabetic cardiomyopathy. It is speculated that this 'gender bias' may be due to gender-related differences in sex hormones and intrinsic myocardial contractile properties. 2. The present study was designed to examine the impact of diabetes and gender on cardiac contractile function and activation of the cardiac survival signalling molecule Akt. Short-term (2 weeks) diabetes was induced in adult mice of both genders with streptozotocin (STZ). Mechanical and intracellular Ca(2+) properties of isolated ventricular myocytes were evaluated using an IonOptix MyoCam system (IonOptix Corporation, Milton, MA, USA). Total and phosphorylated Akt were evaluated using western blot analysis. 3. Female mouse myocytes displayed smaller peak shortening (PS) amplitude and maximal velocity of shortening/relengthening (+/-dL/dt), longer time to PS and time to 90% relengthening compared with male counterparts. Diabetes significantly reduced PS, +/-dL/dt, prolonged TR(90), delayed intracellular Ca(2+) clearing and reduced sarcoplasmic reticulum (SR) Ca(2+) release in male mouse myocytes. All these abnormalities, with the exception of SR Ca(2+), release were masked by the female gender. 4. The negative staircase of PS with increased stimulus frequency (from 0.1 to 5.0 Hz) and protein carbonyl damage were comparable among all animal groups. 5. Female gender and diabetes independently enhanced phosphorylation of Akt without affecting total Akt expression. Interestingly, STZ-induced short-term diabetes failed to elicit additional phosphorylation of Akt in female hearts. 6. In summary, the present data revealed that STZ induced impaired cardiac contractile function and altered intracellular Ca(2+) handling in males, but not females, partially due to intrinsic mechanical differences and Akt activation status between genders.

Effects of prostacyclin in treatment of diabetic nephropathy in rats

Microvascular complications, and primarily diabetic nephropathy, are one of the most severe diabetic complications, which largely influence on prognosis of diabetes in these patients. The etiopathogenesis of this complication is multifactorial one and it has still not been completely elucidated, but includes morphological, pathological-anatomic and biochemical metabolic disorders. It is considered that disorders of endothelial modular function might be critical and initial factor in the development of diabetic vascular complications. Based on pharmacodynamic effects of prostacyclin (PGI2) and its analogues, it could be said that they may be useful in the treatment of diabetic nephropathy. The main aim of this study was to assess the effects of prostacyclin (PGI2) in the treatment of diabetic nephropathy that was experimentally induced with streptozocin. Diabetes was induced in normotensive Wistar strain rats by single i.p. administration of streptozocin (STZ) and as a complication of diabetes and distinct signs and symptoms of diabetic nephropathy (proteinuria, increased serum level of urea and creatinine, polyuria, increased NAG activity in urine). Treatment with prostacyclin (p.o.) at dose of 0.1 mg/kg/b.w./daily during 4 weeks caused a significant reduction of the signs and symptoms of kidney failure as compared to control group of animals that were not given prostacyclin. The results obtained have shown that prostacyclin may have an important role in treatment of diabetic nephropathy, experimentally induced with streptozocin.

Influence of hormone replacement therapy on blood antioxidant enzymes in menopausal women

BACKGROUND

Natural loss of estrogen occurring in menopausal process may contribute to various health problems many of them possibly related to oxidative stress. Hormone replacement therapy (HRT) is the most common treatment to attenuate menopausal disturbances. This study was aimed at evaluating the influence of HRT on the activity of antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT; and glutathione peroxidase, GPx) and lipid peroxidation (thiobarbituric acid reactive substances, TBARS) in menopausal women.

METHODS

Blood antioxidant enzyme activities were determined in premenopausal (n=18) and in postmenopausal healthy women without (n=21) or with (n=19) HRT (mean ages: 47, 59, and 57 years, respectively).

RESULTS

TBARS, CAT, and GPx activity were not significantly different among the groups of study. However, SOD activity was significantly lower in postmenopausal women without HRT (0.68+/-0.04 U/mg Hb) when compared both to premenopausal women (0.91+/-0.04 U/mg Hb) and to postmenopausal women with HRT (0.89+/-0.07 U/mg Hb). SOD activity was positively correlated to the duration of HRT in the postmenopausal groups (r=0.33, p<0.05).

CONCLUSIONS

HRT antagonizes the decrease of SOD activity that occurs after menopause, suggesting that HRT may play a beneficial role in the protection against oxidative stress.

Role of endoethelin-1 in development of neprhopathy induced with streptozocin

The main aim of our study was to detect changes in plasma level of endoethelin-1 after experimentally induced diabetes and diabetic nephropathy with streptozocin in rats. The effects of ACE inhibitors are well known and thus, we wanted to analyze the influence of enalapril (ACE inhibitor) on plasma concentrations of endoethelin-1 as well as its effects in the treatment of diabetic nephropathy. Single i.p. administration of streptozocin (STZ) caused a significant increase of endoethelin-1 plasma concentrations associated with distinct signs and symptoms of diabetic nephropathy (microalbuminuria, increased urine N-acetyl-D-glucosamidase, increased serum concentrations of urea and creatinine, polyuria). Four-week treatment with endoethelin-1 resulted in significant reduction of endoethelin-1 plasma concentrations and improved sings and symptoms of diabetic nephropathy. The results obtained have confirmed that endoethelin-1 may play an important role in development and progression of diabetic nephropathy and ACE inhibitors, that is enalapril, may alleviate and delay the progression of diabetic nephropathy

Insights into the emerging cardiometabolic prevention and management of diabetes mellitus

Cardiovascular disease (CVD) and Type 2 diabetes mellitus (DM2), once conceived as different entities, share common origins and pathways. Increased activity of the renin-angiotensin-aldosterone-system, insulin resistance, chronic low-grade inflammation and oxidative stress collectively contribute to endothelial dysfunction and atherosclerosis, which manifest clinically as CVD. Nowadays, it is possible to identify and intervene in high-risk populations even before the clinical diagnosis of DM2. The control of dietary patterns and increased physical activity is completely feasible, as well as the management of hypertension and dyslipidaemia. Pharmacological interventions targeted at blocking renin-angiotensin-aldosterone-system and sensitising to insulin have a role in the prevention of DM2 and CVD, and are avidly explored worldwide. In the near future, ongoing trials should provide data that will allow us to better treat patients with the cardiometabolic syndrome and diabetes in order to reduce CVD morbidity and mortality.

Sexual dysfunction in women with diabetes mellitus

Sexual problems in men with diabetes mellitus are common and often result from diabetic complications. However, although diabetic complications are similar in both sexes, little attention has been given to the effects of diabetes on female sexuality and sexual function. It is reasonable to suggest that women with diabetes will experience sexual problems due to neuropathy, endocrine changes and vascular complications. However there is little research into the physical effects of diabetes on female sexual function. Reduced vaginal lubrication in women with diabetes has been reported yet this is rarely documented as a sexual problem. Previous studies in women with diabetes may also neglect the importance of the subjective qualities associated with female sexuality and sexual expression.

Oxidative stress and stress signaling: menace of diabetic cardiomyopathy

Cardiovascular disease is the most common cause of death in the diabetic population and is currently one of the leading causes of death in the United States and other industrialized countries. The health care expenses associated with cardiovascular disease are staggering, reaching more than 350 billion dollars in 2003. The risk factors for cardiovascular disease include high fat/cholesterol levels, alcoholism, smoking, genetics, environmental factors and hypertension, which are commonly used to gauge an individual's risk of cardiovascular disease and to track their progress during therapy. Most recently, these factors have become important in the early prevention of cardiovascular diseases. Oxidative stress, the imbalance between reactive oxygen species production and breakdown by endogenous antioxidants, has been implicated in the onset and progression of cardiovascular diseases such as congestive heart failure and diabetes-associated heart dysfunction (diabetic cardiomyopathy). Antioxidant therapy has shown promise in preventing the development of diabetic heart complications. This review focuses on recent advances in oxidative stress theory and antioxidant therapy in diabetic cardiomyopathy, with an emphasis on the stress signaling pathways hypothesized to be involved. Many of these stress signaling pathways lead to activation of reactive oxygen species, major players in the development and progression of diabetic cardiomyopathy.

Therapy Insight: systemic lupus erythematosus as a risk factor for cardiovascular disease

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease with a strong female predilection. Cardiovascular morbidity and mortality is a frequent complication, particularly in females aged 35-44 years, in whom the risk of myocardial infarction is raised 50-fold. The mechanisms underlying this increased risk are not fully understood. Certain traditional risk factors, such as hypertension and diabetes mellitus, are more common in SLE patients than in the general population. These factors do not, however, completely account for the increased cardiovascular risk; factors such as renal impairment, increased homocysteine levels and early menopause probably have a role. In addition, several factors more specifically related to lupus are proposed to be of importance, including chronic inflammation, antiphospholipid antibodies and therapy, especially corticosteroid use. Thus, we need to be proactive in our approach to risk-factor management in SLE patients. Here, we propose that, like diabetes mellitus, SLE should be considered a coronary heart disease equivalent condition for baseline risk and that assessment of cardiovascular risk should be done routinely. In addition to lifestyle modifications, blood pressure and cholesterol levels should be stringently controlled, and administration of aspirin should be considered in selected patients. The increased use of certain interventions, such as statins, also needs to be more widely investigated in this population.

Cardiovascular risk factors in middle-aged women and the association with use of hormone therapy: results from a population-based study of Swedish women. The Women's Health in the Lund Area (WHILA) Study

OBJECTIVE

Cardiovascular diseases in women are multifactorial. Women carry different risk factors compared to men and these specific risk factors need to be delineated, particularly in relation to the hormonal situation, and effects of diet and lifestyle.

METHODS

Out of the total cohort of 10,766 women born 1935-1945 living in the Lund area of southern Sweden, 6917 women completed a generic questionnaire and underwent a physical and laboratory assessment. According to hormonal status, 492 women were premenopausal (PM), 3600 were postmenopausal without hormone therapy (HT) (PM0) and 2816 were postmenopausal with ever-use of HT (PMT). Major cardiovascular risk factors as well as level of education, diet, and degree of physical activity were assessed in relation to hormonal status.

RESULTS

Compared to the PM0 group, the women in the PMT group had a higher level of education, more often worked full time, more often had sedentary work and lived a more regular life. They also had a lower rate of cigarette consumption, lower waist-to-hip ratio and lower body mass index than women in the PM0 group. The PMT group had lower levels of serum total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol and triglycerides than the PM0 group and also had lower systolic and diastolic blood pressures, a lower prevalence of type II diabetes mellitus, of deep venous thrombosis and of coronary artery disease. Low-risk factors for cardiovascular disease and high level of education were still associated with HT, after adjustment by multiple logistic regression. Major risk factors for coronary heart disease were similar between the PM and the PMT groups.

CONCLUSION

Use of HT is accompanied by a lower risk profile for cardiovascular disease and also by several factors indicating a healthier lifestyle.

Non-invasive cardiovascular risk assessment in women with type 2 diabetes

This study assessed and compared carotid intima-media thickness (IMT) in postmenopausal women with type 2 diabetes with that in postmenopausal women without type 2 diabetes and compared risk factors that contribute to increased carotid IMT in these groups of women. Carotid IMT, a non-invasive assessment of cardiovascular risk, was measured using high-resolution ultrasound in 20 postmenopausal women with type 2 diabetes and 20 postmenopausal women without type 2 diabetes who had no known coronary heart disease. Risk factors (age, race, family history, diabetes, hypertension, high cholesterol, years past menopause, use of hormone replacement therapy, perceived level of physical activity, and body mass index) known to contribute to coronary heart disease were also assessed. Mean carotid IMT was .88 mm for women with type 2 diabetes compared with .74 mm for women without type 2 diabetes. There were no differences between groups in age, race, cholesterol, and perceived level of physical activity. Women with type 2 diabetes, however, reported more hypertension ( P = .004), greater body mass index ( P = .026), and less use of hormone replacement therapy ( P = .027). Of concern is that 10% of the women with diabetes had stenosis that required surgical intervention. Findings suggest that carotid IMT is a valid way to screen for cardiovascular risk, particularly in postmenopausal women who are at high risk for coronary heart disease. It may also be a feasible, non-invasive method for the detection and prevention of the macrovascular complications of diabetes.

Diabetes in the elderly and in women: cardiovascular risks

The prevalence of diabetes in the United States is on the rise because of changing characteristics of our population. Ours is an aging population; women who are older than 75 years constitute the fastest growing segment of our population. Our population is increasingly more overweight and sedentary and the numbers of minority persons who have a higher prevalence of obesity and diabetes are on the rise. Currently, at least 17 million persons have known diabetes; another 4 million have the disease but have not been diagnosed. There also is a much larger population-perhaps up to 60 million per-sons-who has the metabolic syndrome. Up to 60% of persons who have essential hypertension have impaired insulin resistance and other characteristics of this syndrome. This article focuses on the metabolic syndrome and diabetes in women and the elderly.

Autocrine activation of the local insulin-like growth factor I system is up-regulated by estrogen receptor (ER)-independent estrogen actions and accounts for decreased ER expression in type 2 diabetic mesangial cells

Autocrine activation of the IGF-I system in mesangial cells (MC) promotes glomerular scarring in a model of type 1 diabetes. Although estrogens protect against progressive nondiabetic glomerulosclerosis (GS), women with diabetes seem to loose the estrogen-mediated protection against cardiovascular disease. However, little is known about the local IGF-I system and its interactions with estrogens in the pathogenesis of type 2 diabetic GS. Therefore, we examined db/db B6 (db/db) mice, a model of type 2 diabetes and diabetic GS. The IGF-I system was activated in the glomeruli and MC of female diabetic db/db mice, but not in nondiabetic db/+ littermates. We found increased IGF-I receptor (IGFR) expression and activation, including activation of MAPK. Surprisingly, estrogens, via an estrogen receptor (ER)-independent mechanism(s), increased IGFR expression, IGFR and insulin receptor substrate phosphorylation, and extracellular signal-regulated kinase activation in db/db MC. In contrast, ER expression was decreased in MC and glomeruli of db/db mice. Treatment with a neutralizing antibody to IGF-I or the MAPK inhibitor PD98059 increased ER expression and transcriptional activity. This suggests that the local prosclerotic IGF-I system is activated in type 2 diabetes and diminishes ER-mediated protection against GS. Although estrogens may stimulate protective ER signaling, they also activate the IGF-I system via ER-independent mechanisms in db/db MC. The later estrogen effects appear to outweigh the antisclerotic effects of ER activation. This may in part account for loss of estrogen protection against the progression of diabetic GS in women with type 2 diabetes.

Control of blood pressure and other cardiovascular risk factors at different practice settings: outcomes of care provided to diabetic women compared to men

Cardiovascular disease (CVD) is the major cause of morbidity and mortality in diabetes. To determine the proportion of patients who met the American Diabetes Association guidelines for control of CVD risk factors and to assess the achievement of these guidelines in women compared with men, we conducted a cross-sectional study of 3678 diabetic cohorts followed at seven medical centers, two Veteran Administration hospitals, three urban clinics, and two suburban clinics. Overall, 28% met the target blood pressure of <130/80 mm Hg, 48.8% achieved a goal low-density lipoprotein cholesterol of <100 mg/dL, and 35.8% had hemoglobin A1c of <7%. Gender comparisons of 2788 diabetic patients at urban and suburban centers showed that women had a lower percentage of low-density lipoprotein cholesterol <100 mg/dL (45.8 vs. 51.3, p<0.01) and a lower percentage of screening for retinopathy (54 vs. 60, p<0.01) and nephropathy (37 vs. 49, p<0.01). However, overall there were no gender differences in the percentage of patients who achieved a goal blood pressure <130/80 mm Hg or hemoglobin A1c <7%. Control of blood pressure and other CVD risk factors in diabetic patients was largely suboptimal, especially for diabetic women. These observations underscore the need for better strategies for control of CVD risk in the diabetic population in general, and women in particular.

Pathobiology and cell interactions of platelets in diabetes

Diabetes is a well-recognised risk factor for atherosclerotic cardiovascular disease and in fact most diabetic patients die from vascular complications. The Diabetes Control and Complications Trial (DCCT) and the U.K. Prospective Diabetes Study (UKPDS) indicate a consistent relationship between hyperglycaemia and the incidence of chronic vascular complications in patients with diabetes. Platelets are essential for haemostasis, and abnormalities of platelet function may cause vascular disease in diabetes. Diabetic patients have hyperreactive platelets with exaggerated adhesion, aggregation and thrombin generation. In summary, the entire coagulation cascade is dysfunctional in diabetes. This review provides a comprehensive overview of the physiological role of platelets in maintaining haemostasis and of the pathophysiological processes that contribute to platelet dysfunction in diabetes and associated cardiovascular diseases, with special emphasis on proteomic approaches and leukocyte-platelet cross-talk.

Protective effects of 17beta-estradiol and trivalent chromium on interleukin-6 secretion, oxidative stress, and adhesion of monocytes: relevance to heart disease in postmenopausal women

Postmenopausal diabetic women are at greater risk for heart disease compared with men of similar age and with other risk factors. We examined the hypothesis that 17beta-estradiol and trivalent chromium inhibit secretion of the pro-inflammatory cytokine interleukin (IL)-6 and oxidative stress in monocytes exposed to high glucose (HG). U937 human monocytes were cultured with HG (30 mM) with and without 17beta-estradiol (0-1000 nM) and chromium chloride (Cr(3+), 0-10 muM) at 37 degrees C for 24 h. Results show that 17beta-estradiol inhibits IL-6 and adhesion to endothelial cells (p <. 05) by HG-treated monocytes. Treatment with 17beta-estradiol+Cr(3+) required a significantly lower dose of estradiol-17beta compared with 17beta-estradiol alone for IL-6 inhibition. 17beta-Estradiol+Cr(3+) also inhibited lipid peroxidation and the adhesivity to human endothelial cells in HG-treated monocytes. Thus, 17beta-estradiol+Cr(3+) inhibits oxidative stress, IL-6 secretion, and monocytic adhesion to endothelial cells, risk factors in the development of heart disease. The female body requires E but studies on some patients indicate side effects with increased amounts of 17beta-estradiol-supplementation. The potential benefit of a lower estrogen dose in combination with chromium is novel and needs to be explored in postmenopausal diabetic women.

Diabetic cardiomyopathy: do women differ from men?

Although many aspects of cardiovascular disease are similar between women and men, it is becoming increasingly obvious that there are significant differences as well. Premenopausal women usually have a lower risk of cardiovascular diseases than age-matched men and postmenopausal women. However, the "female advantage" disappears once women are afflicted with diabetes mellitus. Heart diseases are twice as common in diabetic men and five times as common in diabetic women. It is believed that differences in sex hormones and intrinsic myocardial and endothelial functions between men and women may be responsible for this female "advantage" and "disadvantage" in normal and diabetic conditions. Most experimental and clinical studies on diabetes only included male subjects and failed to address this important gender difference in diabetic heart complications. Although female hearts may be better tolerated to stress (such as ischemia) insults than their male counterparts, female sex hormone such as estrogen may interact with certain risk factors under diabetes which may compromise the overall cardiac function. The benefit versus risk of estrogen replacement therapy on cardiac function and overall cardiovascular health in diabetes remains controversial. This review will focus on gender-related difference in diabetic heart complication--diabetic cardiomyopathy--and if gender differences in intrinsic myocardial contraction, polyol pathway metabolism, and advanced glycation endproduct formation and other neuroendocrinal regulatory mechanisms to the heart may contribute to disparity in diabetic cardiomyopathy between men and women.

The effect of irbesartan in reducing cardiovascular risk in hypertensive type 2 diabetic patients: an observational study in 16,600 patients in primary care

OBJECTIVES

As arterial hypertension substantially increases the risk of premature death, cardiovascular disease and renal insufficiency in patients with type 2 diabetes, effective and safe antihypertensive therapy is of importance. Therefore, the effect of irbesartan as monotherapy, or in fixed combination with hydrochlorothiazide, on blood pressure, metabolic parameters and microalbuminuria and the safety and tolerability of the drug were assessed.

RESEARCH DESIGN AND METHODS

Multicentric, prospective, open phase IV study over 3 months in 16,600 patients with the clinical diagnoses of hypertension and type 2 diabetes. Blood pressure was measured sphygmometrically and albuminuria was assessed with semi-quantitative urine dipsticks.

MAIN OUTCOME MEASURES

Systolic (SBP) and diastolic (DBP) blood pressure reduction, proportion of patients with microalbuminuria and cardiovascular risk calculated based on the SCORE score, each after a follow-up of 3 months compared to baseline. Number and nature of adverse events (AEs).

RESULTS

The sample consisted of 51.3% men, mean age was 62.2+/-10.7 years, 53.9% of patients were overweight and 26.4% were obese. Mean SBP/DBP decrease after 3 months was 22.3/11.2 mmHg. The BP lowering effect was similar in the analyses of various subgroups (according to age group, sex, presence of micro- or macrovascular complications). Irbesartan treatment reduced the percentage of patients with microalbuminuria from 45.6% to 30.6% at 3 months (32.9% relative reduction). Metabolic parameters (lipids, blood glucose, HbA1c) and weight were improved significantly or showed trends for improvement, respectively. The mean 10-year cardiovascular risk as calculated with the SCORE score was decreased from a baseline value of 9.8% to 5.7% (-58% relative reduction). Tolerability was excellent: only 0.3% experienced an AE.

CONCLUSIONS

Treatment with irbesartan in patients with concomitant hypertension and type 2 diabetes led to large blood pressure reductions. In view of the renoprotective effect documented by the reduced rate of patients with albuminuria, and the improvement of further metabolic parameters, these changes translate into a reduction of cardiovascular risk.

Cardiovascular Disease

Health Issue

Cardiovascular disease (CVD) is the leading cause of death in Canadian women and men. In general, women present with a wider range of symptoms, are more likely to delay seeking medial care and are less likely to be investigated and treated with evidence-based medications, angioplasty or coronary artery bypass graft than men.

Key Findings

In 1998, 78,964 Canadians died from CVD, almost half (39,197) were women. Acute myocardial infarction, which increases significantly after menopause, was the leading cause of death among women.

Cardiovascular disease accounted for 21% of all hospital admissions for Canadian women over age 50 in 1999. Admissions to hospital for ischemic heart disease were more frequent for men, but the mean length of hospital stay was longer for women.

Mean blood pressure increases with age in both men and women. After age 65, however, high blood pressure is more common among Canadian women. More than one-third of postmenopausal Canadian women have hypertension.

Diabetes increases the mortality and morbidity associated with CVD in women more than it does in men. Depression also contributes to the incidence and recovery from CVD, particularly for women who experience twice the rate of depression as men.

Data Gaps and Recommendations

CVD needs to be recognized as a woman's health issue given Canadian mortality projections (particularly heart failure). Health professionals should be trained to screen, track, and address CVD risk factors among women, including hypertension, elevated lipid levels, smoking, physical inactivity, depression, diabetes and low socio-economic status.

Progesterone, but not 17β-estradiol, increases TNF-α secretion in U937 monocytes

The Women Health Initiative Clinical trial results suggest that post-menopausal women receiving estrogen + progesterone are at risk for heart disease compared with estrogen alone supplemented women. We examined the hypothesis that progesterone but not 17beta-estradiol (E) increases the secretion of pro-inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha. U937 human monocytes were cultured with normal or high glucose in the presence and absence of estrogen or progesterone at 37 degrees C for 24 h. Results show that estrogen inhibits IL-6 but not TNF-alpha secretion (p < 0.05) in monocytes activated by lipopolysaccharide (LPS) or high glucose. In addition, progesterone increased the TNF-alpha secretion in activated monocytes. Thus, progesterone supplementation along with estrogen may increase blood levels of pro-inflammatory cytokine TNF-alpha and thus risk of heart disease in post-menopausal women.

Phytoestrogenic isoflavones daidzein and genistein reduce glucose-toxicity-induced cardiac contractile dysfunction in ventricular myocytes

Epidemiological evidence suggests a reduction in the incidence of coronary heart disease, cancer and osteoporosis in populations with a high dietary intake of plant estrogen or phytoestrogen. The clinical benefit of phytoestrogens in cereals, vegetables and medicinal plants is attracting increasing attention for the general public. In the present study, we examined the effect of phytoestrogenic isoflavones daidzein and genistein on glucose toxicity-induced cardiac mechanical malfunction simulating diabetic cardiomyopathy. Adult rat ventricular myocytes were isolated and maintained for 24 hours in normal (NG, 5.5 mM) or high glucose (HG, 25.5 mM) medium in the absence or presence of isoflavones daidzein (50 microM) or genistein (20 microM). Cardiac contractile indices were evaluated using an IonOptix MyoCam system including peak shortening (PS), maximal velocity of shortening/relengthening (+/- dL/dt), time-to-PS (TPS) and time-to-90% relengthening (TR90). Myocytes maintained in HG medium displayed altered mechanical function simulating in vivo diabetes including reduced PS, +/- dL/dt and prolonged TR90 associated with normal TPS compared to those from NG myocytes. Interestingly, these HG-induced mechanical dysfunctions were abolished by co-incubation of daidzein or genistein. However, daidzein but not genistein itself depressed PS in NG myocytes. Neither daidzein nor genistein affected any other mechanical parameters tested in NG myocytes. Collectively, these data suggest that the phytoestrogenic isoflavones daidzein and genistein may reduce glucose toxicity-induced cardiac mechanical dysfunction and thus possess therapeutic potential against diabetes-associated cardiac defects.

Insulin and insulin resistance: impact on blood pressure and cardiovascular disease

Cardiovascular disease is a major cause of mortality in individuals with diabetes. Many factors, including hypertension, contribute to the high prevalence of CVD in this population. Hypertension occurs approximately twice as frequently in patients with diabetes compared with patients without diabetes. Conversely, recent data suggest that hypertensive persons are more likely to develop diabetes than normotensive persons. In addition, up to 75% of CVD in patients with diabetes may be attributed to hypertension, leading to recommendations for more aggressive blood pressure control (ie, < 130/85 mm Hg) in persons with coexistent diabetes and hypertension. Increasing obesity further contributes to both diabetes and hypertension and significantly increases CVD morbidity and mortality. Other important risk factors for CVD in these patients include atherosclerosis, dyslipidemia, microalbuminuria, endothelial dysfunction, platelet hyperaggregability, coagulation abnormalities, and diabetic cardiomyopathy. The current knowledge regarding these risk factors has been reviewed, placing special emphasis on the metabolic syndrome, hypertension, microalbuminuria, and the role of obesity in these disorders. Although not discussed in detail, it is acknowledged that both hygienic measures (weight loss and aerobic exercise) and treatment strategies that include aspirin, statins, INS sensitizers, and antihypertensive agents that reduce renin-angiotensin-aldosterone system activity have been shown to reduce inflammation, coagulation abnormalities, endothelial function, proteinuria, and in some cases reduce CVD and renal disease progression. Additional therapeutic agents are currently being developed specifically to improve INS sensitivity and other CVD risk factors that are components of the cardiometabolic syndrome.