CVD Affects Women With Diabetes More Than Men

Fran Lowry

April 12, 2013

Women with diabetes have a greater risk for death than men with diabetes, especially if the disease goes undiagnosed for a long time, according to new research published online April 5 in Diabetes Care.

"Cardiovascular disease [CVD] in particular has a greater impact on females with diabetes than males, especially when the disease is diagnosed late, as is often the case," coauthor Madonna M. Roche, MSC, from the research and evaluation department, Newfoundland and Labrador Centre for Health Information, St. John's, told Medscape Medical News.

"Clinicians could consider glucose control in addition to CVD risk factors when designing treatment strategies for patients, recognizing that female patients may be at higher risk than males for adverse outcomes," Ms. Roche suggested.

In Canada, as elsewhere, the incidence and prevalence of diabetes have been increasing in recent years. All too often, type 2 diabetes is diagnosed late, sometimes as long as 9 to 12 years after the disease develops, and as a result, complications are often present at the time of diagnosis, she said.

Madonna M. Roche

"Newfoundland and Labrador have the highest age-standardized prevalence of diabetes in Canada, and the age-standardized mortality and hospitalization rates for CVD, acute myocardial infarction [AMI], and stroke are some of the highest in the country," she noted.

The current study aimed to compare the risk for all-cause, CVD, AMI, and stroke mortality and hospitalizations for men and women with and without diabetes, as well those with early and late diagnoses of diabetes.

The retrospective cohort study used several administrative databases in Newfoundland and Labrador and included 73,783 individuals aged 25 years or older. The mean age of the sample was 60.1 years (standard deviation [SD], 14.3 years); 51.2% (n = 37,790) were men and 48.8% (n = 35,993) were women. About half of the cohort lived in a rural area. Similar proportions of men (20.5%, n = 7751) and women (20.6%, n = 7401) had diabetes.

Of the 15,152 individuals who had diabetes, 9517 had late diagnoses, so defined as "late" because they had comorbidities related to diabetes at the time they were diagnosed.

Both men and women with diabetes were more likely to die, to be younger at death, to have a shorter survival time, and to be admitted to hospitals than men and women without diabetes (P < .01). However, these risks were stronger in women than in men.

The hazard ratio [HR] for all-cause mortality in women with diabetes was 1.85 (95% confidence interval [CI], 1.74 – 1.96), and the HR for CVD hospitalizations was 2.57 (95% CI, 2.24 – 2.94).

In comparison, the HR for all-cause mortality in men with diabetes was 1.59 (95% CI, 1.51 – 1.69), and the HR for CVD hospitalizations was 1.92 (95% CI, 1.72 – 2.14).

A late diagnosis of diabetes conferred an even greater risk of CVD mortality and hospitalizations for women.

Compared with women with no diabetes, the HR for CVD mortality in women with a late diabetes diagnosis was 6.54 (95% CI, 4.80 – 8.91), and their HR for CVD hospitalizations was 5.22 (95% CI, 4.31 – 6.33).

In addition, compared with men with no diabetes, the HR for CVD mortality in women with a late diabetes diagnosis was 3.44 (95% CI, 2.47 – 4.79) and HR for CVD hospitalizations was 3.33 (95% CI, 2.80 – 3.95).

Treatment Plans Should Be Individualized

Ms. Roche suggests that treatment strategies for men and women should be individualized based on patient age, duration of diabetes, hypoglycemia risk, and presence or absence of CVD.

"Perhaps the focus should be on not only glucose control but rather all CVD risk factors, recognizing that female patients may be at a higher risk than males for adverse outcomes," she said.

Cardiovascular risk factors may have a stronger effect on women than on men. Also, CVD risk factors tend to be less aggressively treated in women. In addition, data from the Newfoundland and Labrador Component of the Canadian Community Health Survey show that women with diabetes are less likely to use insulin, to have their hemoglobin A1c levels tested, or to be prescribed aspirin and cholesterol-lowering medications than are men with diabetes, Roche said.

"We hope that this study will raise awareness of the increased risk of mortality and hospitalization outcomes that females have when diabetes is present," she said.

Ms. Roche has reported no relevant financial relationships.

Diabetes Care. Published online April 5. Abstract