Sex Differences in the Cardiovascular Consequences of Diabetes Mellitus: A Scientific Statement From the American Heart Association

Cisplatin Nephrotoxicity Might Have a Sex Difference. An analysis Based on Women's Sex Hormone Changes

Background: A sex difference in cisplatin-induced nephrotoxicity (CIN) has been reported in human and animal studies. We examined in humans whether it is associated with sex-hormone changes. Methods: In this retrospective nationwide cohort study, we used Taiwan's National Health Insurance Research Database (NHIRD) to identify patients with a history of malignancy and cisplatin treatment. Patients diagnosed with kidney disease before cisplatin treatment and those with sex-organ malignancies were excluded. A diagnosis of kidney disease within 90 days after the first administration of cisplatin was the study outcome. Risk factors were estimated using a Cox regression model. Subgroup analyses were performed based on different women's estrogen levels in phases of childbearing, perimenopause, and postmenopause. Results: A retrospective analysis of the records of 3973 men (mean age: 56.15 ± 12.85 years) and 1154 women (mean age: 56.31 ± 12.40 years) showed that 1468 (36.95%) men and 451 (39.08%) women had a new diagnosis of kidney disease. The risk factors were being > 55 years old, a high comorbidity score, and a history of aminoglycoside treatment. Only postmenopausal women had a significantly higher risk of kidney injury (hazard ratio: 1.28; 95% CI: 1.02-1.61) than did men. Conclusions: Perimenopausal women have a significantly higher risk of CIN than do men, which might be explained by women's higher levels of estrogen. Additional studies on the underlying mechanisms of the sex difference of CIN are needed.

Gender Disparities in Lipid Goal Attainment among Type 2 Diabetes Outpatients with Coronary Heart Disease: Results from the CCMR-3B Study

Our study was aimed to investigate the gender disparities in lipid goal attainment among type 2 diabetes outpatients with concomitant coronary heart disease (CHD) and explore potential risk factors. We performed the present analysis using data from a nationally representative epidemiologic study. The therapeutic goal was defined as achieving a low-density lipoprotein cholesterol (LDL-C) <1.8 mmol/L. A total of 1721 male and 2072 female type 2 diabetes outpatients with established CHD were identified. Compared with men, women had higher levels of total cholesterol (4.98 vs. 4.46 mmol/L; p < 0.001), LDL-C (2.82 vs. 2.54 mmol/L; p < 0.001), and triglycerides (2.02 vs. 1.79 mmol/L; p < 0.001), but not hemoglobin A1c (7.47% vs. 7.50%; p = 0.597). The proportion of women received lipid-lowering therapy was lower (38.1% vs. 48.2%; p < 0.001). The percentages of patients who achieved the LDL-C goal were higher among men. Multivariable regression analysis indicated that the odds ratio for lipid goal attainment due to the gender difference was 0.61 after adjusting confounders. The inability to achieve LDL-C goals in women with type 2 diabetes and CHD is apparently greater than that in men. This finding underscores the importance of initiatives to establish a more aggressive lipid management strategy for women to overcome gender imbalances.

Plasma Retinol-Binding Protein 4 Levels and the Risk of Ischemic Stroke among Women

BACKGROUND

Plasma retinol-binding protein 4 (RBP4) levels have been associated with cardiovascular risk factors and risk of coronary heart disease, but little is known about the association between RBP4 and the risk of ischemic stroke. We hypothesized that elevated RBP4 levels would be associated with an increased risk of ischemic stroke among women.

METHODS

We performed a nested case-control study among women enrolled in the Nurses' Health Study who provided blood samples between 1989 and 1990 and were free of prior stroke and cancer. We measured prediagnostic RBP4 levels in 471 ischemic stroke cases who were confirmed by medical record review and in 471 controls who were matched 1:1 to the cases on age, race, blood collection date, menopausal status, postmenopausal hormone use, and smoking status. We analyzed the association between RBP4 levels and ischemic stroke using multivariable conditional logistic regression conditional on the matching factors and adjusted for physical activity, body mass index, aspirin use, alcohol consumption, diet, history of diabetes, high cholesterol, high blood pressure, or heart disease, and cholesterol and hemoglobin A1C levels.

RESULTS

Median levels of RBP4 were similar in cases (31.1 µg/mL) and controls (31.0 µg/mL; P value from the Wilcoxon rank-sum test = .82). Quartiles of RBP4 were not associated with an increased risk of ischemic stroke (highest quartile compared to lowest quartile: multivariate-adjusted odds ratio, .75; 95% confidence interval, .48, 1.17). We also did not observe associations between RBP4 and ischemic stroke of thrombotic or embolic origin.

CONCLUSIONS

Elevated levels of RBP4 were not associated with an increased risk of ischemic stroke.

Physical inactivity and cardiac events: An analysis of the Detection of Ischemia in Asymptomatic Diabetics (DIAD) study

AIMS

Diabetes affects 29 million adults, and the majority have type 2 diabetes (T2D). Coronary artery disease (CAD) is the leading cause of death, and physical inactivity is an important risk factor. The aims of this study were to examine the contribution of physical inactivity to CAD events, and to identify the independent predictors of CAD events in a sample of older adults with T2D.

METHOD

A secondary data analysis of the prospective randomized screening trial "Detection of Ischemia in Asymptomatic Diabetics (DIAD)" study. Cox proportional hazard modeling was used to examine the outcome of CAD events.

RESULTS

During the five years of follow-up, the CAD event rate for all subjects (n = 1119) was 8.4% (n = 94). In unadjusted analysis, physical inactivity was significantly associated with development of a CAD event. In the final model, nine baseline variables were significant predictors (p < 0.05) of a CAD: physical inactivity, race, diabetes duration, hemoglobin A1c (HbA1c), peripheral numbness, insulin use, increasing waist-to-hip ratio, family history of premature CAD, and a higher pulse pressure. In men only, there were five predictors (p < 0.05) of a CAD event: diabetes duration, peripheral numbness, HbA1c, increasing waist-to-hip ratio, and higher pulse pressure. The final model in women included three independent predictors (p < 0.05) of a CAD event: diabetes duration, a family history of premature CAD, and higher pulse pressure.

CONCLUSION

Several variables predicted CAD events in this sample of older adults with T2D. Understanding baseline characteristics that heighten risk may assist providers in intervening early to prevent its occurrence.

Gender differences in hospital admissions for major cardiovascular events and procedures in people with and without diabetes in England: a nationwide study 2004-2014

Background

Secondary prevention of cardiovascular disease (CVD) has improved immensely during the past decade but controversies persist on cardiovascular benefits among women with diabetes. We investigated 11-year trends in hospital admission rates for acute myocardial infarction (AMI), stroke, percutaneous coronary intervention (PCI), and coronary artery bypass graft (CABG) in people with and without diabetes by gender in England.

Methods

We identified all hospital admissions for cardiovascular disease causes among people aged 17 years and above between 2004 and 2014 in England. We calculated diabetes-specific and non-diabetes-specific rates for study outcomes by gender. To assess temporal changes, we fitted negative binomial regression models.

Results

Diabetes-related admission rates remained unchanged for AMI (incidence rate ratio (IRR) 0.99 [95% CI 0.98–1.01]), increased for stroke by 2% (1.02 [1.01–1.03]) and PCI by 3% (1.03 [1.01–1.04]) and declined for CABG by 3% (0.97 [0.96–0.98]) annually. Trends did not differ significantly by diabetes status. Women with diabetes had significantly lower rates of AMI (IRR 0.46 [95% CI 0.40–0.53]) and stroke (0.73 [0.63–0.84]) compared with men with diabetes. However, gender differences in admission rates for AMI attenuated in diabetes compared with the non-diabetic group. While diabetes tripled admission rates for AMI in men (IRR 3.15 [95% CI 2.72–3.64]), it increased it by over fourfold among women (4.27 [3.78–4.93]). Furthermore, while the presence of diabetes was associated with a threefold increased rates for PCI and fivefold increased rates for CABG (IRR 3.14 [2.83–3.48] and 5.01 [4.59–5.05], respectively) in men, among women diabetes was associated with a 4.4-fold increased admission rates for PCI and 6.2-fold increased rates for CABG (4.37 [3.93–4.85] and 6.24 [5.66–6.88], respectively). Proportional changes in rates were similar in men and women for all study outcomes, leaving the relative risk of admissions unchanged.

Conclusions

Diabetes still confers a greater increase in risk of hospital admission for AMI in women relative to men. However, the absolute risk remains higher in men. These results call for intensified CVD risk factor management among people with diabetes, consideration of gender-specific treatment targets and treatment intensity to be aligned with levels of CVD risk.

Amiloride Improves Endothelial Function and Reduces Vascular Stiffness in Female Mice Fed a Western Diet

Obese premenopausal women lose their sex related cardiovascular disease protection and develop greater arterial stiffening than age matched men. In female mice, we have shown that consumption of a Western diet (WD), high in fat and refined sugars, is associated with endothelial dysfunction and vascular stiffening, which occur via activation of mineralocorticoid receptors and associated increases in epithelial Na⁺ channel (ENaC) activity on endothelial cells (EnNaC). Herein our aim was to determine the effect that reducing EnNaC activity with a very-low-dose of amiloride would have on decreasing endothelial and arterial stiffness in young female mice consuming a WD. To this end, we fed female mice either a WD or control diet and treated them with or without a very-low-dose of the ENaC-inhibitor amiloride (1 mg/kg/day) in the drinking water for 20 weeks beginning at 4 weeks of age. Mice consuming a WD were heavier and had greater percent body fat, proteinuria, and aortic stiffness as assessed by pulse-wave velocity than those fed control diet. Treatment with amiloride did not affect body weight, body composition, blood pressure, urinary sodium excretion, or insulin sensitivity, but significantly reduced the development of endothelial and aortic stiffness, aortic fibrosis, aortic oxidative stress, and mesenteric resistance artery EnNaC abundance and proteinuria in WD-fed mice. Amiloride also improved endothelial-dependent vasodilatory responses in the resistance arteries of WD-fed mice. These results indicate that a very-low-dose of amiloride, not affecting blood pressure, is sufficient to improve endothelial function and reduce aortic stiffness in female mice fed a WD, and suggest that EnNaC-inhibition may be sufficient to ameliorate the pathological vascular stiffening effects of WD-induced obesity in females.

Sex differences in micro- and macro-vascular complications of diabetes mellitus

Vascular complications are a leading cause of morbidity and mortality in both men and women with type 1 (T1DM) or type 2 (T2DM) diabetes mellitus, however the prevalence, progression and pathophysiology of both microvascular (nephropathy, neuropathy and retinopathy) and macrovascular [coronary heart disease (CHD), myocardial infarction, peripheral arterial disease (PAD) and stroke] disease are different in the two sexes. In general, men appear to be at a higher risk for diabetic microvascular complications, while the consequences of macrovascular complications may be greater in women. Interestingly, in the absence of diabetes, women have a far lower risk of either micro- or macro-vascular disease compared with men for much of their lifespan. Thus, the presence of diabetes confers greater risk for vascular complications in women compared with men and some of the potential reasons, including contribution of sex hormones and sex-specific risk factors are discussed in this review. There is a growing body of evidence that sex hormones play an important role in the regulation of cardiovascular function. While estrogens are generally considered to be cardioprotective and androgens detrimental to cardiovascular health, recent findings challenge these assumptions and demonstrate diversity and complexity of sex hormone action on target tissues, especially in the setting of diabetes. While some progress has been made toward understanding the underlying mechanisms of sex differences in the pathophysiology of diabetic vascular complications, many questions and controversies remain. Future research leading to understanding of these mechanisms may contribute to personalized- and sex-specific treatment for diabetic micro- and macro-vascular disease.

Impaired endothelium-derived hyperpolarization-type relaxation in superior mesenteric arteries isolated from female Otsuka Long-Evans Tokushima Fatty rats

Endothelium-derived hyperpolarization (EDH) is an important signaling mechanism of endothelium-dependent vasorelaxation, and little attention has been paid to the EDH-type responses in female metabolic syndrome such as that observed with type-2 diabetes. We previously reported that EDH-type relaxation was impaired in superior mesenteric arteries from male Otsuka Long-Evans Tokushima Fatty (OLETF) rat, a model of type-2 diabetes, however, the response was unclear in female OLETF rat. Thus, the aim of this study was to examine if EDH-type relaxation was altered in superior mesenteric arteries isolated from female OLETF rats compared to age-matched, control female Long-Evans Tokushima Otsuka (LETO) rats at age 50-59 weeks. We investigated concentration-relaxation curves for acetylcholine (at age 50-53 weeks), NS309 (an activator of small- and intermediate-conductance calcium-activated potassium channels) (at age 50-53 weeks), and GSK1016790A (an agonist of transient receptor potential vanilloid type 4, TRPV4) (at age 58 or 59 weeks) in the presence of the nitric oxide synthase inhibitor N^G-nitro-L-arginine and the cyclooxygenase inhibitor indomethacin to investigate EDH-type responses in the superior mesenteric artery. Obesity, mild hyperglycemia, hyperinsulinemia, and hyperlipidemia (i.e., increased total cholesterol, triglyceride, and non-esterified fatty acids) were more frequent in OLETF rats than in age-matched LETO rats at age 50-53 weeks. Acetylcholine-, NS309-, and GSK1016790A-induced relaxations in arteries from OLETF rats were all significantly reduced compared to those in LETO rats. These results indicated that EDH-type relaxations were impaired in female OLETF rats. This novel experimental model may provide new insights into vascular dysfunction in metabolic syndrome in females.

Influence of sex on cardiovascular drug responses: role of estrogen

In this review we discuss the sex/estrogen-specific modulation of cardiovascular function and responses to current therapeutics. We discuss how anatomical differences such as a smaller kidney size, and lower glomerular filtration rate in females, reduce the clearance and increase the toxicity of some drugs in females. Other important sex differences include the dampening effect of estrogen on central sympathetic and renin angiotensin systems. Further, we discuss how a shift in myocardial redox status leads to paradoxical transformation of estrogen into a pro-inflammatory hormone. Finally, the review, along with cited recent publications, identify some areas that need further investigation to advance our understanding of the sex differences in cardiovascular disease outcomes to help develop female specific interventions for these anomalies.

Ischemia and No Obstructive Coronary Artery Disease (INOCA): Developing Evidence-Based Therapies and Research Agenda for the Next Decade

The Cardiovascular Disease in Women Committee of the American College of Cardiology, in conjunction with interested parties (from the National Heart, Lung, and Blood Institute, American Heart Association, and European Society of Cardiology), convened a working group to develop a consensus on the syndrome of myocardial ischemia with no obstructive coronary arteries. In general, these patients have elevated risk for a cardiovascular event (including acute coronary syndrome, heart failure hospitalization, stroke, and repeat cardiovascular procedures) compared with reference subjects and appear to be at higher risk for development of heart failure with preserved ejection fraction. A subgroup of these patients also has coronary microvascular dysfunction and evidence of inflammation. This document provides a summary of findings and recommendations for the development of an integrated approach for identifying and managing patients with ischemia with no obstructive coronary arteries and outlines knowledge gaps in the area. Working group members critically reviewed available literature and current practices for risk assessment and state-of-the-science techniques in multiple areas, with a focus on next steps needed to develop evidence-based therapies. This report presents highlights of this working group review and a summary of suggested research directions to advance this field in the next decade.

Prediction of Cardiovascular Disease by the Framingham-REGICOR Equation in the High-Risk PREDIMED Cohort: Impact of the Mediterranean Diet Across Different Risk Strata

BACKGROUND

The usefulness of cardiovascular disease (CVD) predictive equations in different populations is debatable. We assessed the efficacy of the Framingham-REGICOR scale, validated for the Spanish population, to identify future CVD in participants, who were predefined as being at high-risk in the PREvención con DIeta MEDiterránea (PREDIMED) study-a nutrition-intervention primary prevention trial-and the impact of adherence to the Mediterranean diet on CVD across risk categories.

METHODS AND RESULTS

In a post hoc analysis, we assessed the CVD predictive value of baseline estimated risk in 5966 PREDIMED participants (aged 55-74 years, 57% women; 48% with type 2 diabetes mellitus). Major CVD events, the primary PREDIMED end point, were an aggregate of myocardial infarction, stroke, and cardiovascular death. Multivariate-adjusted Cox regression was used to calculate hazard ratios for major CVD events and effect modification from the Mediterranean diet intervention across risk strata (low, moderate, high, very high). The Framingham-REGICOR classification of PREDIMED participants was 25.1% low risk, 44.5% moderate risk, and 30.4% high or very high risk. During 6-year follow-up, 188 major CVD events occurred. Hazard ratios for major CVD events increased in parallel with estimated risk (2.68, 4.24, and 6.60 for moderate, high, and very high risk), particularly in men (7.60, 13.16, and 15.85, respectively, versus 2.16, 2.28, and 3.51, respectively, in women). Yet among those with low or moderate risk, 32.2% and 74.3% of major CVD events occurred in men and women, respectively. Mediterranean diet adherence was associated with CVD risk reduction regardless of risk strata (P>0.4 for interaction).

CONCLUSIONS

Incident CVD increased in parallel with estimated risk in the PREDIMED cohort, but most events occurred in non-high-risk categories, particularly in women. Until predictive tools are improved, promotion of the Mediterranean diet might be useful to reduce CVD independent of baseline risk.

CLINICAL TRIAL REGISTRATION

URL: http://www.Controlled-trials.com. Unique identifier: ISRCTN35739639.

Sex-gender-related therapeutic approaches for cardiovascular complications associated with diabetes

Diabetes is a chronic disease associated with micro- and macrovascular complications and is a well-established risk factor for cardiovascular disease. Cardiovascular complications associated with diabetes are among the most important causes of death in diabetic patients. Interestingly, several sex-gender differences have been reported to significantly impact in the pathophysiology of diabetes. In particular, sex-gender differences have been reported to affect diabetes epidemiology, risk factors, as well as cardiovascular complications associated with diabetes. This suggests that different therapeutic approaches are needed for managing diabetes-associated cardiovascular complications in men and women. In this review, we will discuss about the sex-gender differences that are known to impact on diabetes, mainly focusing on the cardiovascular complications associated with the disease. We will then discuss the therapeutic approaches for managing diabetes-associated cardiovascular complications and how differences in sex-gender can influence the existing therapeutic approaches.

New directions for diabetes prevention and management in behavioral medicine

Accelerating diabetes rates have resulted in a global public health epidemic. Lifestyle change is a cornerstone of care, yet regimen demands may result in adherence difficulties. Distress, depression, and other psychosocial concerns are higher in those with diabetes. While interventions, such as the Diabetes Prevention Program appear to be effective, further research is needed to support the translation of interventions to prevent diabetes. Studies assessing optimal approaches to promoting effective decision making, coping and adherence are needed. More information is needed to evaluate the influence and potential of emerging technologies on intervention delivery and quality of life in children and adults with diabetes. Theoretically informed, interdisciplinary studies that consider ecological models are needed to develop a roadmap for policies and diabetes management recommendations. Reduction of diabetes-related health disparities is a critical area for future studies. Behavioral medicine scientists and practitioners are poised to address these and other proposed future research directions to advance diabetes prevention and management.

Intrauterine growth restriction influences vascular remodeling and stiffening in the weanling rat more than sex or diet

Intrauterine growth restriction (IUGR) increases the incidence of adult cardiovascular disease (CVD). The sex-specific developmental mechanisms for IUGR-induced and Western high-fat diet (HFD) modification of CVD remain poorly understood. We hypothesized a maternal HFD in the Sprague-Dawley rat would augment IUGR-induced CVD in the offspring through decreased cardiac function and increased extracellular matrix (ECM) remodeling and stiffness in a sex-specific manner. HFD or regular diet (Reg) was given from 5 wk before mating through postnatal day (PND) 21. IUGR was induced by uterine artery ligation at embryonic day 19.5 (term = 21.5 days). At PND 21, echocardiographic assessments were made and carotid arteries tested for vascular compliance using pressure myography. Arterial samples were quantified for ECM constituents or fixed for histologic evaluation. The insult of IUGR (IUGR + Reg and IUGR + HFD) led to increased mechanical stiffness in both sexes ( P < 0.05). The combination of IUGR + HFD increased diastolic blood pressure 47% in males (M) and 35% in females (F) compared with the Con + Reg ( P < 0.05). ECM remodeling in IUGR + HFD caused fewer (M = −29%, F = −24%) but thicker elastin bands (M = 18%, F = 18%) and increased total collagen (M = 49%, F = 34%) compared with Con + Reg arteries. Remodeling in IUGR + HFD males increased medial collagen and soluble collagen ( P < 0.05). Remodeling in IUGR + HFD females increased adventitial collagen and wall thickness ( P < 0.05) and decreased matrix metalloproteinase 2 (MMP-2), advanced glycosylation end products (AGE), and receptor AGE (RAGE; P < 0.05). In summary, both IUGR + Reg and IUGR + HFD remodel ECM in PND 21 rats. While IUGR + HFD increases blood pressure, IUGR but not HFD increases vascular stiffness suggesting a specific mechanism of vascular remodeling that can be targeted to limit future disease.

NEW & NOTEWORTHY We report intrauterine growth restriction (IUGR) increases vascular stiffening in both male and female rats through increased collagen content and altered elastin structure more than a high-fat diet (HFD) alone. Our study shows the importance of stiffness supporting the hypothesis that there are physiologic differences and potential windows for early intervention targeting vascular remodeling mechanisms.

Gender difference in diabetes related excess risk of cardiovascular events: When does the 'risk window' open?

OBJECTIVE

Women with diabetes have a greater excess risk for cardiovascular diseases (CVD) than men. This study was aimed at clarifying whether this effect is lifelong or more evident in some life-periods.

METHODS

The effect of diabetes and gender on the risk of first ever hospitalization for acute myocardial infarction (AMI), ischemic stroke (IS), congestive heart failure (CHF), lower extremity amputations (LEA) or any of these major cardiovascular events (MACE) have been evaluated by a Cox-hazard model, over years 2008-2012 querying administrative databases of a cohort living in Tuscany, Italy.

RESULTS

Comparing subjects with diabetes to those without it the overall age-adjusted excess risk was higher in women than in men for AMI and MACE and higher in men for LEA, with no difference for IS or CHF. In women the excess risk for AMI and MACE started earlier (46yr) and lasted until age of more than 85yr, while 'risk-windows' opened later and had a shorter duration for CHF (56-65yr) and IS (66-75yr).

CONCLUSION

Diabetic women have a significant diabetes-associated excess of CVD risk, except for LEA, with a 'risk window' opening earlier and lasting longer for AMI and MACE, later and with a shorter duration for IS and CHF.

Sex Differences in the Effect of Type 2 Diabetes on Major Cardiovascular Diseases: Results from a Population-Based Study in Italy

The aim of the study is to assess sex difference in association between type 2 diabetes and incidence of major cardiovascular events, that is, myocardial infarction, stroke, and heart failure, using information retrieved by diabetes register. The inhabitants of Reggio Emilia (Italy) aged 30-84 were followed during 2012-2014. Incidence rate ratios and 95% confidence intervals were calculated using multivariate Poisson model. The age- and sex-specific event rates were graphed. Subjects with type 2 diabetes had an excess risk compared to their counterparts without diabetes for all the three major cardiovascular events. The excess risk is similar in women and men for stroke (1.8 times) and heart failure (2.7 times), while for myocardial infarction, the excess risk in women is greater than the one observed in men (IRR 2.58, 95% CI 2.22-3.00 and IRR 1.78, 95% CI 1.60-2.00, resp.; P of interaction < 0.0001). Women had always a lesser risk than men, but in case of myocardial infarction, the women with type 2 diabetes lost part of advantage gained by women free of diabetes (IRR 0.61, 95% CI 0.53-0.72 and IRR 0.36, 95% CI 0.33-0.39, resp.). In women with type 2 diabetes, the risk of major cardiovascular events is anticipated by 20-30 years, while in men it is by 15-20.

Excess Cardiovascular Risk in Women Relative to Men Referred for Coronary Angiography Is Associated With Severely Impaired Coronary Flow Reserve, Not Obstructive Disease

BACKGROUND

Cardiovascular disease (CVD) fatality rates are higher for women than for men, yet obstructive coronary artery disease (CAD) is less prevalent in women. Coronary flow reserve (CFR), an integrated measure of large- and small-vessel CAD and myocardial ischemia, identifies patients at risk for CVD death, but is not routinely measured in clinical practice. We sought to investigate the impact of sex, CFR, and angiographic CAD severity on adverse cardiovascular events.

METHODS

Consecutive patients (n=329, 43% women) referred for invasive coronary angiography after stress testing with myocardial perfusion positron emission tomography and with left ventricular ejection fraction >40% were followed (median, 3.0 years) for a composite end point of major adverse cardiovascular events, including cardiovascular death and hospitalization for nonfatal myocardial infarction or heart failure. The extent and severity of angiographic CAD were estimated by using the CAD prognostic index, and CFR was quantified by using positron emission tomography.

RESULTS

Although women in comparison with men had lower pretest clinical scores, rates of prior myocardial infarction, and burden of angiographic CAD (P<0.001), they demonstrated greater risk of CVD events, even after adjustment for traditional risk factors, imaging findings, and early revascularization (adjusted hazard ratio, 2.05; 95% confidence interval, 1.05-4.02; P=0.03). Impaired CFR was similarly present among women and men, but in patients with low CFR (<1.6, n=163), women showed a higher frequency of nonobstructive CAD, whereas men showed a higher frequency of severely obstructive CAD (P=0.002). After also adjusting for CFR, the effect of sex on outcomes was no longer significant. When stratified by sex and CFR, only women with severely impaired CFR demonstrated significantly increased adjusted risk of CVD events (P<0.0001, P for interaction=0.04).

CONCLUSIONS

Women referred for coronary angiography had a significantly lower burden of obstructive CAD in comparison with men but were not protected from CVD events. Excess cardiovascular risk in women was independently associated with impaired CFR, representing a hidden biological risk, and a phenotype less amenable to revascularization. Impaired CFR, particularly absent severely obstructive CAD, may represent a novel target for CVD risk reduction.

Women's health: a new global agenda

Global efforts to improve the health of women largely focus on improving sexual and reproductive health. However, the global burden of disease has changed significantly over the past decades. Currently, the greatest burden of death and disability among women is attributable to non-communicable diseases (NCDs), most notably cardiovascular diseases, cancers, respiratory diseases, diabetes, dementia, depression and musculoskeletal disorders. Hence, to improve the health of women most efficiently, adequate resources need to be allocated to the prevention, management and treatment of NCDs in women. Such an approach could reduce the burden of NCDs among women and also has the potential to improve women's sexual and reproductive health, which commonly shares similar behavioural, biological, social and cultural risk factors. Historically, most medical research was conducted in men and the findings from such studies were assumed to be equally applicable to women. Sex differences and gender disparities in health and disease have therefore long been unknown and/or ignored. Since the number of women in studies is increasing, evidence for clinically meaningful differences between men and women across all areas of health and disease has emerged. Systematic evaluation of such differences between men and women could improve the understanding of diseases, as well as inform health practitioners and policymakers in optimising preventive strategies to reduce the global burden of disease more efficiently in women and men.

Antimüllerian hormone among women with and without type 1 diabetes: the Epidemiology of Diabetes Interventions and Complications Study and the Michigan Bone Health and Metabolism Study

OBJECTIVE

To compare concentrations of antimüllerian hormone (AMH) in women with and without type 1 diabetes.

DESIGN

Cross-sectional analysis of longitudinal studies, adjusting for repeated measures.

SETTING

Not applicable.

PATIENT(S)

Women aged 30-45 years who had not undergone oophorectomy, hysterectomy, or natural menopause at the time of AMH measurement were included (n = 376 in the Michigan Bone Health and Metabolism Study and n = 321 in the Epidemiology of Interventions and Complications Study). Linear mixed regression was used to evaluate whether AMH concentrations differed by diabetes status, adjusting for repeated measurements of AMH within individual women, body mass index, smoking status, and oral contraceptive use.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Concentrations of AMH.

RESULT(S)

In unadjusted comparisons, women with and without diabetes had similar median AMH values before 35 years of age, although women with type 1 diabetes had a lower proportion of women with elevated AMH concentrations (≥5.0 ng/dL). After adjustment for covariates and multiple observations per woman, log AMH concentrations were significantly lower among women with type 1 diabetes compared with women without diabetes (β-coefficient -1.27, 95% confidence interval [-2.18, -0.36] in fully adjusted models) before 35 years of age.

CONCLUSION(S)

Before 35 years of age, women with type 1 diabetes have lower AMH levels than women without diabetes. Further investigation is needed to determine the etiologies of this difference and how it may contribute to reproductive disorders among women with type 1 diabetes.

Reduced Subendocardial Viability Ratio Is Associated With Unfavorable Cardiovascular Risk Profile in Women With Short Duration of Type 2 Diabetes

BACKGROUND

The pathophysiological perturbations underlying the unfavorable cardiovascular prognosis in women with type 2 diabetes (T2DM) remain elusive. Low subendocardial viability ratio (SEVR), an index of myocardial oxygen supply and demand, has been associated with intermediate cardiovascular risk markers and cardiovascular mortality in various populations. However, whether SEVR is associated with sex and cardiovascular risk markers in patients with T2DM remains to be clarified.

METHODS

We examined 86 T2DM patients (mean age 59±10 years, 47% women, median diabetes duration 1.9 (range 0.2-5.0) years) and 86 sex- and age-matched control subjects in a cross-sectional study. SEVR was noninvasively assessed by tonometry and markers of cardiovascular risk by carotid-femoral pulse wave velocity (PWV), homeostasis model assessment of insulin resistance (HOMA2-IR), C-reactive protein, urinary albumin/creatinine ratio, and heart rate variability.

RESULTS

Women with diabetes had significantly lower SEVR compared to both men with diabetes (161% ± 26% vs. 178% ± 32%, P < 0.01), women without diabetes (185% ± 24%, P < 0.001), and men without diabetes (188% ± 28%, P < 0.001). The differences remained significant after adjustment for age, systolic blood pressure, heart rate, diabetes, and smoking. SEVR was associated with PWV, HOMA2-IR, C-reactive protein, and reduced heart rate variability in patients and control subjects, but the associations became nonsignificant after adjustment for heart rate.

CONCLUSIONS

SEVR is reduced in women with short duration of T2DM and associated with cardiovascular risk markers. The latter association seems to be at least partly mediated via heart rate. We hypothesize that reduced SEVR may contribute to the unfavorable cardiovascular prognosis in women with diabetes.

Pregnancy history and blood-borne microvesicles in middle aged women with and without coronary artery calcification

BACKGROUND AND AIMS

Having a history of preeclampsia increases the risk for future coronary artery calcification (CAC). This study evaluated the association of blood-borne, cell-derived microvesicles (MV) with CAC in middle-aged women.

METHODS

Twelve pre-selected, antigen-specific MV were measured by digital flow cytometry in the blood of age- and parity-matched women (median age 60 years) without a history of cardiovascular events, but with either a history of preeclampsia (PE, n = 39) or normotensive pregnancy (NP, n = 40). CAC was determined by computed tomography.

RESULTS

CAC scores ranged from 0 to 47 and 0-602 Agatston Units in the NP and PE groups, respectively. Waist circumference and insulin resistance were greatest in PE women with CAC. MV positive for tissue factor or stem/progenitor cell antigen (CD117) differed between NP and PE groups. In univariate analysis, those positive for tissue factor, ICAM-1, stem cells, and adipocytes (P16-set) antigens associated with CAC in the PE group. Principal components (PC) analysis reduced the MV variables to three independent dimensions. PC1 showed a modest correlation with CAC scores in the PE group (ρ = 0.31, p = 0.06) and associated with CAC in a multivariable model on pooled groups that included all 3 PC variables when adjusted for pregnancy status (p = 0.03). The association was lost when corrected for body mass index or waist circumference.

CONCLUSIONS

In women with a history of PE and elevated metabolic risk profile, a group of specific antigen-positive MV associated with CAC. These MV may reflect cellular processes associated with CAC. Their diagnostic potential for CAC remains to be determined.

Diabetic dyslipidaemia

PURPOSE OF REVIEW

The purpose is to discuss recent developments in the understanding of lipoprotein metabolism in diabetes, the cardiovascular risk associated with both type 1 and type 2 diabetes, recently published guidelines on the management of this risk, concerns over the use of statin treatment in diabetes, and other therapeutic options.

RECENT FINDINGS

Diabetic dyslipidaemia can be gross with massive hypertriglyceridemia, or subtle with a lipid profile which would be regarded as normal in a nondiabetic patient, but which hides underlying increases in atherogenic subfractions of LDL (e.g., small dense LDL, glycated LDL) and remnant lipoproteins. Statins can decrease these without the clinician being aware from routine biochemistry. In type 2 diabetes, HDL cholesterol levels are often reduced, whereas in type 1, insulin can raise HDL, but its antiatherogenic properties are compromised. Dyslipidaemia and hypertension predate the onset of glycaemia of diabetic proportions (metabolic syndrome). Obese people can thus die of diabetes before they develop it. Obesity should be prevented and treated. Statins decrease the risk of cardiovascular disease in diabetes or metabolic syndrome regardless of whether glycaemia worsens.

SUMMARY

One unassailable truth is that statin therapy is beneficial and should rarely, if ever, be withheld.

Youth with type 1 diabetes have worse strain and less pronounced sex differences in early echocardiographic markers of diabetic cardiomyopathy compared to their normoglycemic peers: A RESistance to InSulin in Type 1 ANd Type 2 diabetes (RESISTANT) Study

OBJECTIVE

Diabetic cardiomyopathy is a major cause of morbidity, but limited data are available on early cardiac abnormalities in type 1 diabetes (T1D). We investigated differences in myocardial strain in adolescents with and without T1D. We hypothesized that adolescents with T1D would have worse strain than their normoglycemic peers, which boys would have worse strain than girls, and that strain would correlate with glycemic control and adipokines.

METHODS

We performed fasting laboratory measures and echocardiograms with speckle tracking to evaluate traditional echocardiographic measures in addition to longitudinal (LS) and circumferential (CS) strain, and in adolescents (15±2years) with (19 boys; 22 girls) and without (16 boys; 32 girls) type 1 diabetes.

RESULTS

Compared to controls, adolescents with type 1 diabetes had significantly lower CS (-20.9 vs. -22.7%, p=0.02), but not LS (p=0.83). Boys with T1D had significantly lower LS than girls with T1D (-17.5 vs. -19.7%, p=0.047), adjusted for Tanner stage. The significant sex differences observed in indexed left ventricular mass, left end-diastolic volume, diastolic septal and posterior wall thickness in our controls were lacking in adolescents with T1D.

CONCLUSIONS

Our observations suggest that youth with T1D have worse myocardial strain than normoglycemic peers. In addition, the relatively favorable cardiac profile observed in girls vs. boys in the control group, was attenuated in T1D. These early cardiovascular changes in youth with T1D are concerning and warrant longitudinal and mechanistic studies.

Epidemiology of Obesity and Diabetes and Their Cardiovascular Complications

Obesity and diabetes mellitus have reached epidemic proportions in the past few years. During 2011 to 2012, more than one-third of the US population was obese. Although recent trend data indicate that the epidemic has leveled off, prevalence of abdominal obesity continues to rise, especially among adults. As seen for obesity, the past few decades have seen a doubling of the diabetes mellitus incidence with an increasing number of type 2 diabetes mellitus cases being diagnosed in children. Significant racial and ethnic disparities exist in the prevalence and trends of obesity and diabetes mellitus. In general, in both adults and children, non-Hispanic blacks and Mexican Americans seem to be at a high risk than their non-Hispanic white counterparts. Secular changes in agricultural policies, diet, food environment, physical activity, and sleep have all contributed to the upward trends in the diabesity epidemic. Despite marginal improvements in physical activity and the US diet, the food environment has changed drastically to an obesogenic one with increased portion sizes and limited access to healthy food choices especially for disadvantaged populations. Interventions that improve the food environment are critical as both obesity and diabetes mellitus raise the risk of cardiovascular disease by ≈2-fold. Among those with type 2 diabetes mellitus, significant sex differences occur in the risk of cardiovascular disease such that diabetes mellitus completely eliminates or attenuates the advantages of being female. Given the substantial burden of obesity and diabetes mellitus, future research efforts should adopt a translational approach to find sustainable and holistic solutions in preventing these costly diseases.

Metabolic memory phenomenon in diabetes mellitus: Achieving and perspectives

Diabetes mellitus (DM) exhibits raised prevalence worldwide. There is a large body of evidence regarding the incidence of DM closely associates with cardiovascular (CV) complications. In this context, hyperglycaemia, oxidant stress, and inflammation are key factors that contribute in CV events and disease in type1 and type 2 DM, even when metabolic control was optimal and/or intensive glycemic control was implemented. It has been suggested that the effect of poor metabolic control or even transient episodes of hyperglycemia in DM associates in particularly with worsening ability of endogenous vasoreparative systems that are mediated epigenetic changes in several cells (progenitor cells, stem cells, mononuclears, immune cells), and thereby lead to so called "vascular glycemic memory" or "metabolic memory". Both terms are emphasized the fact that prior glucose control has sustained effects that persist even after return to more usual glycemic control. The mechanisms underlying the cellular "metabolic memory" induced by high glucose remain unclear. The review is discussed pathophysiology and clinical relevance of "metabolic" memory phenomenon in DM. The role of oxidative stress, inflammation, and epigenetics in DM and its vascular complications are highlighted. The effects of several therapeutic approaches are discussed.

Sex-specific differential in risk of diabetes-related macrovascular outcomes

Reports from recent studies suggest that diabetes confers a higher risk of cardiovascular disease in women compared to men. Larger studies, including meta-analyses, report that women with diabetes have a 44 % greater risk of incident coronary heart disease and a 27 % greater risk of incident stroke compared to men with diabetes. In this article, we summarize results from longitudinal studies that examine sex differences in risk factors for and rates of macrovascular complications from diabetes. We also discuss possible mechanisms for increased cardiovascular risk associated with diabetes in women compared to men, including the clustering of hypertension, obesity, and elevated triglycerides, the possible contribution of hormonal differences, and sex differences in the prescription of and adherence to pharmacologic treatment. In conclusion, diabetes is associated with a slightly higher risk of cardiovascular disease in women compared to men. Future studies should further explore the reasons underlying imperfect use of medications that lower cardiovascular risk in both women and men with diabetes.