April 2014 Issue
The Diabetes and Heart Disease Link
By Constance Brown-Riggs, MSEd, RD, CDE, CDN
Vol. 16 No. 4 P. 12
Controlling blood sugar and lowering blood pressure and lipids can prevent heart disease in diabetes patients.
Diabetes is the seventh leading cause of death in the United States, and heart disease is the leading cause of death and disability in people with diabetes. In fact, the American Heart Association estimates that at least 68% of people aged 65 and older with diabetes die from some form of heart disease and 16% die of stroke.
Heart disease death rates among adults with diabetes are two to four times higher than the rates for adults without diabetes. The burden of heart disease among children with diabetes is substantial, and the signs of heart disease likely will appear before the onset of puberty.1,2
This article explores the link between diabetes and heart disease and provides advice for dietitians on how to counsel clients and patients.
The link between diabetes and heart disease is complex and multifactorial. Atherosclerosis, a major risk factor for heart disease, significantly threatens the macrovasculature of patients with diabetes.3 Dyslipidemia is highly correlated with atherosclerosis, and up to 97% of patients with diabetes are dyslipidemic.3 Together with smoking and hypertension, dyslipidemia disturbs endothelial function in various ways that accelerate atherosclerotic changes, including increased smooth muscle constriction of the coronary artery, enhanced thrombosis, and increased local inflammatory responses.4
Moreover, it appears the effects of these risk factors may be synergistic rather than just additive. In the National Cholesterol Education Program (NCEP) Adult Treatment Panel III (ATP-III), diabetes counts as a heart disease risk equivalent because it confers a high risk of heart disease within 10 years, in part because of its frequent association with multiple risk factors. According to the Joslin Diabetes Center, more than 90% of patients with diabetes have one or more of the previously mentioned risk factors.
Unfortunately, as evidenced by the National Institutes of Health’s Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) study, children with type 2 diabetes have a more aggressive and difficult-to-manage illness than is seen in adults, but they exhibit the same cardiovascular risk factors, such as high blood pressure and high cholesterol.5
The TODAY study found that 11% of kids with adolescent-onset type 2 diabetes had high blood pressure at the beginning of the study, while 33% had high blood pressure by the end of the study five years later. A similar 10% increase was seen in the kids with high cholesterol during the course of the study.
“These study results tell us that the disease process is accelerated in young people with type 2 diabetes,” says Patricia Kringas, RN, BSN, MA, CDE, a TODAY study research coordinator and certified diabetes educator at the Naomi Berrie Diabetes Center in New York. Worse yet, heart disease will become prevalent in the third and fourth decades of life in these adolescents.
Controlling Risk Factors
Numerous studies have shown the efficacy of controlling individual risk factors in preventing or slowing heart disease in people with diabetes.6 Risk factor reduction includes control of hyperglycemia, hypertension, and lipids.
“There’s a strong relationship between diabetes and heart disease, and it begins with high blood sugar levels,” says Margaret O’Halloran, MS, RD, CDE, CDN, senior clinical dietitian at St Francis Hospital—The Heart Center in Roslyn, New York.
Increasing evidence suggests that treating blood glucose may reduce long-term heart disease rates, particularly in those newly diagnosed. In a 10-year follow-up study of participants in the UK Prospective Diabetes Study (UKPDS), those originally randomized to intensive glucose control had significant long-term reductions in heart disease and all-cause mortality.6
Controlling blood pressure in people with diabetes can reduce overall cardiovascular mortality and, in particular, the incidence of stroke. The UKPDS showed that even modest blood pressure reduction is beneficial. Study participants in the intensive group, on average, reached a blood pressure of 144/82 mm Hg compared with the control group’s 154/87 mm Hg. Diabetes-related death was reduced by 32% and stroke by 44%.4 The American Diabetes Association recommends a target blood pressure level of less than 140/80 mm Hg for adults with diabetes.
Lifestyle modification, including weight reduction, adoption of the DASH eating plan, increased physical activity, and moderation of alcohol consumption, is essential in the management of hypertension with or without diabetes.4
Ninety-five percent of people with diabetes have some type of lipid disorder. The combination of high triglycerides and low HDL cholesterol is most common. The concentration of LDL cholesterol is similar to that of the nondiabetic population. Numerous studies have found that each of the lipoprotein abnormalities of diabetes is a heart disease risk predictor. Treatment to lower LDL cholesterol and triglycerides or raise HDL cholesterol has been shown to reduce heart disease risk in people with diabetes.4
Therapeutic intervention for dyslipidemia includes lifestyle change and pharmacologic therapy. The American Diabetes Association and the NCEP ATP III recommend a step-wise approach, starting with therapeutic lifestyle change as an initial step. If, after a six-week trial of therapeutic lifestyle change, the person hasn’t reached LDL cholesterol goals, the NCEP ATP III recommends pharmacologic intervention.
People with clinical evidence of heart disease should be considered for pharmacologic lipid-lowering therapy starting at the same time as therapeutic lifestyle change.4
Patients need to understand their risk of heart disease and individual goals for diabetes management (“their numbers”). They can be taught the elements of risk factor reduction—hyperglycemia, hypertension, and hyperlipidemia—using the “ABCs of Diabetes,” which are (hemoglobin) A1c, blood pressure, and cholesterol.
“In the hospital setting, working with the health care team to identify at-risk patients is key,” O’Halloran says. “On admission, blood glucose levels, A1c, and BMI are used as screening tools in the process. When at-risk patients are identified, as the registered dietitian and certified diabetes educator, it’s my job to provide MNT [medical nutrition therapy] to them.”
Ximena Jimenez, MS, RDN, LD, a national spokesperson for the Academy of Nutrition and Dietetics, believes it’s important to accentuate the positive: “I emphasize positive changes they can do. My patients are looking for healthful food alternatives rather than foods to avoid.”
“Much of the approach to helping patients take control of this disease hinges on a healthy dialogue with the patient and his or her family,” O’Halloran says. “A few simple questions to a patient can open a dialogue that may encourage them to understand diabetes and how to avoid its complications.” The dialogue can help ensure that intervention strategies are culturally and age sensitive.
For example, “Some of my patients who are 60 years old or above and Latinos don’t care for brown rice,” says Jimenez, who suggests finding out what foods they enjoy that are heart healthy. For instance, “Latinos love black beans, red kidney beans, and garbanzo beans,” she says.
Heart disease is the leading cause of death and disability in people with diabetes, but nutrition therapy that includes a dietitian who develops an individualized eating pattern designed to lower glucose and blood pressure levels and alter lipid profiles can help manage diabetes as well as lower heart disease and stroke risk.
— Constance Brown-Riggs, MSEd, RD, CDE, CDN, is the national spokesperson for the Academy of Nutrition and Dietetics, specializing in African American nutrition, and author of the African American Guide to Living Well With Diabetes and Eating Soulfully and Healthfully With Diabetes.
1. Early signs of heart disease in preadolescent children with type 1 diabetes. Science Daily website. http://www.sciencedaily.com/releases/2011/02/110214155501.htm. February 11, 2011. Accessed February 6, 2014
2. Babar GS, Zidan H, Widlansky ME, et al. Impaired endothelial function in preadolescent children with type 1 diabetes. Diabetes Care. 2011;34(3):681-685.
3. Dokken BB. The pathophysiology of cardiovascular disease and diabetes: beyond blood pressure and lipids. Diabetes Spectrum. 2008;21(3):160-165.
4. Mensing C (ed). The Art and Science of Diabetes Self-Management Education Desk Reference. 2nd ed. Chicago, IL: American Association of Diabetes Educators; 2011.
5. Adolescent type 2 diabetes: a high risk condition for early cardiovascular disease. Naomi Berrie Diabetes Center, Columbia University Medical Center website. http://nbdc.cumc.columbia.edu/news/adolescent-type-2-diabetes. October 17, 2013. Accessed February 6, 2014
6. American Diabetes Association. Standards of medical care in diabetes—2014. Diabetes Care. 2014;37 Suppl 1:S14-80.