Gender differences in cardiovascular risk profiles and diabetes care among adults with type 2 diabetes in Germany

Diabetes and cardiovascular risk according to sex: An overview of epidemiological data from the early Framingham reports to the cardiovascular outcomes trials

Male sex is a major cardiovascular risk factor in the general population, with men showing higher age-adjusted prevalence of cardiovascular disease than women. Diabetes, another major cardiovascular risk factor, affects cardiovascular risk differentially between men and women. Data from prospective observational studies showed that women with diabetes had greater relative risk of cardiovascular events than men with diabetes, leading to a smaller difference between diabetic men and women than between non-diabetic men and women in terms of cardiovascular disease. This excess relative risk concerns cardiovascular death, coronary heart disease, stroke and heart failure. It is greatest in the youngest age group and decreases gradually with age. Although many mechanisms have been proposed to explain the greater cardiovascular burden in women with diabetes, little is known about the impact of diverse anti-hyperglycemic drugs on cardiovascular events according to sex. Hence, cardiovascular outcomes trials provide a unique opportunity to study the impact of novel anti-hyperglycemic drugs on cardiovascular outcomes in men and women with type-2 diabetes. Here, we present an overview of the epidemiological data concerning sex-related differences in cardiovascular disease in people with diabetes, with a focus on the effects of novel anti-hyperglycemic drugs on cardiovascular outcomes in men and women. In addition, we summarize proposed mechanisms to explain these differences, with relevant references for the interested reader.

Gender-associated cardiometabolic risk profiles and health behaviors in patients with type 2 diabetes: a cross-sectional analysis of the Joint Asia Diabetes Evaluation (JADE) program

Background

In Asia, diabetes-associated death due to cardiorenal diseases were 2-3 times higher in women than men which might be due to gender disparity in quality of care and health habits.

Methods

Adults with type 2 diabetes (T2D) from 11 Asian countries/areas were assessed using the same protocol (2007-2015). We compared treatment target attainment (HbA_1c < 7%, blood pressure [BP] < 130/80 mmHg, risk-based LDL-cholesterol, lack of central obesity [waist circumference <90 cm in men or <80 cm in women), use of cardiorenal-protective drugs (renin-angiotensin system [RAS] inhibitors, statins), and self-reported health habits including self-monitoring blood glucose (SMBG) by gender. Analyses were stratified by countries/areas, age of natural menopause (<50 vs. ≥50 years), and comorbidities (atherosclerotic cardiovascular disease [ASCVD], heart failure, kidney impairment [eGFR < 60 mL/min/1.73 m²]).

Findings

Among 106,376 patients (53.2% men; median (interquartile range) diabetes duration: 6.0 (2.0-12.0) years; mean ± SD HbA_1c 8.0 ± 1.9%; 27% insulin-treated), women were older and less likely to receive college education than men (28.9% vs. 48.8%). Women were less likely to smoke/drink alcohol and were physically less active than men. Women had lower BP (<130/80 mmHg: 29.4% vs. 25.7%), less general obesity (54.8% vs. 57.8%) but more central obesity than men (77.5% vs. 57.3%). Women were less likely to have ASCVD (12.8% vs. 17.0%) or heart failure (1.3% vs. 2.3%), but more likely to have kidney impairment (22.3% vs. 17.6%) and any-site cancer than men (2.5% vs. 1.6%). In most countries/areas, more men attained HbA_1c <7% and risk-based LDL-cholesterol level than women. After adjusting for potential confounders including countries and centres, men had 1.63 odds ratio (95% CI 1.51, 1.74) of attaining ≥3 treatment targets than women.

Interpretation

Asian women with T2D had worse quality of care than men especially in middle-income countries/areas, calling for targeted implementation programs to close these care gaps.

Sponsor

Asia Diabetes Foundation.

Funding

Nil.

Investigating the protective effects of estrogen on β-cell health and the progression of hyperglycemia-induced atherosclerosis

Sex differences in the prevalence and development of diabetes and associated cardiometabolic complications are well established. The objective of this study was to analyze the effects of estrogen on the maintenance of β-cell health/function and atherosclerosis progression, using a mouse model of hyperglycemia-induced atherosclerosis, the ApoE^-/-:Ins2^+/Akita mouse. ApoE^-/-:Ins2^+/Akita mice exhibit sexual dimorphism in the control of blood glucose levels. Male ApoE^-/-:Ins2^+/Akita mice are chronically hyperglycemic due to a significant reduction in pancreatic β-cell mass. Female mice are only transiently hyperglycemic, maintain β-cell mass, and blood glucose levels normalize at 35 ± 1 days of age. To determine the effects of estrogen on pancreatic β-cell health and function, ovariectomies and estrogen supplementation experiments were performed, and pancreatic health and atherosclerosis were assessed at various time points. Ovariectomized ApoE^-/-:Ins2^+/Akita mice developed chronic hyperglycemia with significantly reduced β-cell mass. To determine whether the observed effects on ovariectomized ApoE^-/-:Ins2^+/Akita mice were due to a lack of estrogens, slow-releasing estradiol pellets were inserted subcutaneously. Ovariectomized ApoE^-/-:Ins2^+/Akita mice treated with exogenous estradiol showed normalized blood glucose levels and maintained β-cell mass. Exogenous estradiol significantly reduced atherosclerosis in both ovariectomized female and male ApoE^-/-:Ins2^+/Akita mice relative to controls. Together, these findings suggest that estradiol confers significant protection to pancreatic β-cell health and can directly and indirectly slow the progression of atherosclerosis.NEW & NOTEWORTHY This study examines the effect(s) of estrogen on β cell and cardiometabolic health/function in a novel mouse model of hyperglycemia-induced atherosclerosis (ApoE^-/-:Ins2^+/Akita). Using a combination of estrogen deprivation (ovariectomy) and supplementation strategies, we quantify effects on glucose homeostasis and atherogenesis. Our results clearly show a protective role for estrogen on pancreatic β-cell health and function and glucose homeostasis. Furthermore, estrogen supplementation dramatically reduces atherosclerosis progression in both male and female mice.

Sex Disparities in Cardiovascular Risk Factor Assessment and Screening for Diabetes-Related Complications in Individuals With Diabetes: A Systematic Review

Background

Insight in sex disparities in the detection of cardiovascular risk factors and diabetes-related complications may improve diabetes care. The aim of this systematic review is to study whether sex disparities exist in the assessment of cardiovascular risk factors and screening for diabetes-related complications.

Methods

PubMed was systematically searched up to April 2020, followed by manual reference screening and citations checks (snowballing) using Google Scholar. Observational studies were included if they reported on the assessment of cardiovascular risk factors (HbA1c, lipids, blood pressure, smoking status, or BMI) and/or screening for nephropathy, retinopathy, or performance of feet examinations, in men and women with diabetes separately. Studies adjusting their analyses for at least age, or when age was considered as a covariable but left out from the final analyses for various reasons (i.e. backward selection), were included for qualitative analyses. No meta-analyses were planned because substantial heterogeneity between studies was expected. A modified Newcastle-Ottawa Quality Assessment Scale for cohort studies was used to assess risk of bias.

Results

Overall, 81 studies were included. The majority of the included studies were from Europe or North America (84%).The number of individuals per study ranged from 200 to 3,135,019 and data were extracted from various data sources in a variety of settings. Screening rates varied considerably across studies. For example, screening rates for retinopathy ranged from 13% to 90%, with half the studies reporting screening rates less than 50%. Mixed findings were found regarding the presence, magnitude, and direction of sex disparities with regard to the assessment of cardiovascular risk factors and screening for diabetes-related complications, with some evidence suggesting that women, compared with men, may be more likely to receive retinopathy screening and less likely to receive foot exams.

Conclusion

Overall, no consistent pattern favoring men or women was found with regard to the assessment of cardiovascular risk factors and screening for diabetes-related complications, and screening rates can be improved for both sexes.

Social inequality and diabetes mellitus - developments over time among the adult population in Germany

The connection between social disadvantage and the presence of known diabetes and specific risk factors is well documented. This article summarises the results from the Robert Koch Institute examination surveys that were conducted between 1997 and 1999 as well as 2008 and 2011 to address social inequality - operationalised by level of education - with regard to prevalences of known and unknown diabetes, risk of diabetes and care of diabetes as well as their development over time. Both survey periods showed that the low education group has higher prevalences of known and unkown diabetes as well as a higher risk of developing diabetes within the next five years compared to the medium and high education group. Over time, prevalence tended to increase for known diabetes and to decrease for unknown diabetes for all education groups. For the 5-year diabetes risk, only the high education group showed a clear decrease over time. The chosen indicators of diabetes care indicated no clear differences between education groups and an improvement of diabetes care over time. For some indicators of care (foot examination, statins), improvements were only seen in the low education group. In conclusion, social inequalities in the prevalence of known and unknown diabetes as well as in diabetes risk remain in Germany; for the indicators of care, however, no clear education gradient is evident. Over time, inequality regarding the prevalence of diabetes has not increased further. However, with regard to diabetes risk, inequality has become slightly more evident. For individual care indicators, improvements are limited to specific education groups.