Diabetes and Cardiovascular Disease in Older Adults: Current Status and Future Directions

Jeffrey B. Halter; Nicolas Musi; Frances McFarland Horne; Jill P. Crandall; Andrew Goldberg; Lawrence Harkless; William R. Hazzard; Elbert S. Huang; M. Sue Kirkman; Jorge Plutzky; Kenneth E. Schmader; Susan Zieman; Kevin P. High

Disclosures

Diabetes. 2014;63(8):2578-2589. 

In This Article

Epidemiology of Diabetes and Concomitant CVD in an Aging Population

Among adults aged 65 years or older in the U.S., the combined prevalence of prediabetes and diabetes (both diagnosed and undiagnosed) ranges from 50 to 80%, depending on which measures of hyperglycemia are used.[1] Approximately $300 billion is spent annually on patients with diabetes in the U.S., and the majority of these costs is spent on older adults with long-standing diabetes and severe complications.[6] With the baby-boom cohort reaching the geriatric age range, the number of new diabetes cases is expected to increase, even if prevention efforts are somewhat successful.

Prevalence of diagnosed and undiagnosed diabetes is higher among Mexican Americans, African Americans, and Asian Americans than it is among white Americans. Although disparities are apparent in access to care in the U.S., Diabetes Study of Northern California (DISTANCE) data (see Table 1 for study names and descriptions) indicate marked racial and ethnic disparities in the prevalence and incidence of diabetes and cardiovascular outcomes, even in a population with uniform access to care.[7] Furthermore, there is substantial heterogeneity within large ethnic groups. For example, incidence and prevalence vary widely in subpopulations of Asian Americans. These disparities are similar between men and women but recent evidence suggests that they are magnified among adults older than 60 years.

Individuals with diagnosed diabetes are at higher risk for coronary heart disease (CHD),[8] but CHD risk also is elevated modestly among individuals with prediabetes, defined as fasting plasma glucose concentrations of 100–125 mg/dL. Data from the National Diabetes Surveillance System indicate that the incidence of several diabetes-related complications, including hyperglycemic death, amputation, stroke, and ischemic heart disease (IHD), declined substantially between 1989 and 2009, particularly among older patients. Although relative glucose-related risk for CHD appears to decrease with age,[9] the overall absolute risk for CVD increases dramatically with age,[9] and age strongly predicts diabetes-related congestive heart failure (CHF), IHD, and stroke (Fig. 1).

Figure 1.

Incidence (per 1,000) of major diabetes complications among adults with diabetes, by age, 2009. Source: National Diabetes Surveillance System, available from https://www.cdc.gov/diabetes. CHF, congestive heart failure; ER, emergency room; ESRD, end-stage renal disease; IHD, ischemic heart disease.

Fasting plasma glucose concentration is a risk factor for CVD. However, the association of fasting glucose with CHD is more moderate than other risk factors such as total cholesterol, non-HDL cholesterol, and particularly systolic blood pressure, which has a relationship with CHD that is nearly log linear.[8] The 2-h plasma glucose concentration during an oral glucose tolerance test (OGTT) is a strong determinant of cardiovascular risk. OGTT-defined prediabetes and diabetes predict incidence of CVD and death, even after accounting for corresponding categories based on fasting plasma glucose.[4] Duration of diabetes likewise appears to be an important determinant for the development of CVD. Risk for heart failure or stroke is higher among individuals with a history of diabetes than among those newly diagnosed,[10] and diagnosed diabetes is an equivalent risk factor to previous myocardial infarction (MI) among men aged 60–79 years with earlier—but not recent—onset diabetes.[11]

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