Volume 1 number 1 Summer 2003
Special issue for the abstracts of the 7th Pan Arab Conference on Diabetes
PACD7 , 25 – 28 March 2003 Cairo

Abstract Number : 69
Diabetes and Cardiovascular Diseases

John B. Buse, MD, PhD, CDE , USA

Cardiovascular disease (CVD) is a major complication and the leading cause of premature death among people with diabetes. Adults with diabetes are two to four times more likely to have heart disease or suffer a stroke than people without diabetes. CVD claimed more than $7 billion of the $44.1 billion annual direct medical costs for diabetes in 1997 in the United States, the most costly of all complications of type 2 diabetes (1). While in the US there has been an overall decrease in mortality due to CVD over the past 30 years, people with diabetes have not benefited from this decline. In fact, deaths due to CVD in women with diabetes have increased (2). Also troubling are results from a recent study that shows that the prevalence of diabetes has increased 49% from 1990 to 2000 and projections indicate a 165% increase by the year 2050 (3). The diabetes epidemic in the US foreshadows grave difficulties for healthcare systems worldwide in coping with the likely morbidity and mortality associated with diabetes as a result of a progressively sedentary lifestyle accompanied with ready availability of high caloric density foods. 

To help reduce the morbidity and mortality associated with diabetic CVD in the US, the American Diabetes Association (ADA) and the American College of Cardiology (ACC) recently launched an initiative, “Make the Link! Diabetes, Heart Disease and Stroke.” The initiative’s goals are to increase public awareness of CVD and diabetes, decrease the incidence of CVD associated with diabetes, educate healthcare providers on proper CVD diagnosis and treatment, and inform patients on their risk and appropriate therapies. As part of this initiative, the two organizations commissioned a survey to assess physicians’ attitudes and practices in managing cardiovascular risk factors in patients with diabetes. The survey obtained baseline data on how seriously physicians view the cardiovascular risks of diabetes, how they discuss these risks with their patients, and what they believe are the most significant barriers to effectively managing these risks. Prior to this survey, a study was performed on people with diabetes to determine how much they know about their increased risks for CVD and if they are talking with their doctor about these risks. The following paragraphs summarize their findings and discuss their implications for clinical care.

Survey Methodologies 
The physician survey was performed on a representative national sample of approximately 700 primary care physicians, 100 cardiologists, and 100 endocrinologists. A marketing information services company, TargetRx, fielded it online in March of 2002. The survey of 2,008 people with diagnosed diabetes was conducted August-October 2001 by market research firm RoperASW using random direct dial screenings of U.S. households. Results were weighted and projected to match the U.S. diagnosed patient population of 10.7 million based on an extrapolation of estimates provided by the National Center for Health Statistics and Centers for Disease Control and Prevention. 

Key Findings – Physicians’ Attitudes and Practices
Results from the physician survey indicate a high level of awareness among physicians of the CVD risks associated with diabetes. Ninety-one percent of physicians believe that their patients with diabetes are “very” or “extremely” likely to have a cardiovascular event. This proportion is higher than for any other CVD risk factor indicating that physicians recognize the extraordinary risk associated with diabetes. Physicians ranked lowering blood glucose as the top treatment priority (63%) for reducing CVD risks in their patients with diabetes, with only 22% indicating that blood pressure treatment was the highest priority and only 7% identifying cholesterol management as the highest priority. Physicians perceive “poor compliance” with behavioral modifications and complex medication regimens as the top two barriers to effectively managing CVD risks in patients with diabetes. Only 24% of physicians report that lack of time to effectively counsel patients is a barrier. Physicians perceive that diabetes patients are significantly less likely than non-diabetic patients with CVD to be at treatment goals for blood pressure and lipids. Physicians report discussing managing cardiovascular risk factors with the majority (88 percent) of their diabetes patients, and almost all physicians (95 percent) report initiating these discussions. However, physicians feel their patients with diabetes are only moderately knowledgeable of their increased risk for a cardiovascular event. 

Key Findings – Patient Awareness of Cardiovascular Risks
These queries of people with diabetes showed that more than two-thirds do not consider CVD to be a serious complication of diabetes. People with diabetes are more likely to be aware of serious diabetes complications causing disability such as blindness (65 percent) or amputation (36 percent) rather than complications that may result in premature death such as heart disease (17 percent), heart attack (14 percent) or stroke (5 percent). According to the survey, the perception of personal CVD risks is low. More than half of people with diabetes does not feel at risk for a heart condition (52 percent) or stroke (53 percent). Nearly two thirds (60 percent) do not feel at risk for either high blood pressure or high cholesterol. People with diabetes ³ 65 years of age feel the least amount of risk for cardiovascular disease. Few people with diabetes could name important methods to reduce their risk of heart attack or stroke, such as taking prescription medications (18 percent), lowering cholesterol (8 percent), quitting smoking (7 percent), reducing blood pressure (5 percent) and taking aspirin (1 percent). Sixteen percent of the survey respondents could not name any way to reduce their cardiovascular disease risk. People with diabetes report seeing their health care provider about five times a year, and almost 75 percent say they ask questions about managing their diabetes. Two thirds of people with diabetes report discussing blood sugar control at every or some visit. About half report that their healthcare provider never discussed lowering blood pressure (52 percent) or lowering cholesterol (45 percent). Among smokers, more than one third said quitting smoking was not discussed.

Conclusions
The results of the physician and patient surveys demonstrate the critical need to improve communication between physicians and their patients about the link between diabetes and cardiovascular disease. While there is a high level of awareness among physicians of the CVD risks associated with diabetes, patients with diabetes have limited knowledge of these risks. Cardiovascular disease is the leading cause of diabetes-related deaths, but the majority of people with diabetes are more fearful of complications such as blindness and amputation. While three quarters self-reported experiencing cardiovascular complications such as high blood pressure, high cholesterol, or stroke, they failed to link these problems with their diabetes. Physicians say they are talking to their patients about their increased risk for cardiovascular complications, but those warnings do not seem to be resonating with the affected patient population. We may need to investigate and better understand what is happening. Are people with diabetes “hearing” about blood pressure and cholesterol, but not linking these conditions to their diabetes? Do people with diabetes consider these to be separate diseases? Diabetes is a complex disease that requires continuing medical care and life-long patient education. The survey results repeatedly reinforce this complexity and highlight treatment compliance challenges associated with behavioral changes, as well as multiple medication regimens. Physicians’ belief that diabetes patients are less likely to be at treatment goals than non-diabetic patients with cardiovascular disease further underscores the difficulty in managing diabetes-related cardiovascular risk factors. The effort required to self-manage diabetes on a daily basis may also negatively impact one’s ability to effectively treat other risk factors such as high blood pressure and cholesterol. Strategies for improving patient compliance with lifestyle modifications and multiple drug therapies should be explored. The majority of physicians surveyed identified lowering blood glucose as their top priority to reduce cardiovascular event in-patients with diabetes. While a focus on glucose control is important to minimize the risk of microvascular complications, since there are no definitive clinical trial data demonstrating that intensified glycemic control significantly reduces risk of CVD, many would argue that control of blood pressure and lipids, smoking cessation and use of aspirin may be more important to reduce the life-threatening cardiovascular complications. In fact, the Centers for Disease Control’s Cost Effectiveness Group recently published an analysis that suggests that intensified blood pressure control be cost saving (4). 
Most of the discussion during the presentation will review the evidence base for the American Diabetes Association’s comprehensive recommendations regarding management of cardiovascular risk. Table 1 includes a summary of key clinical goal (5).

Table 1: American Diabetes Association Clinical Goals Aimed at Reducing CVD Risk

* Full text of the American Diabetes Association’s clinical practice recommendations is available online at http://care.diabetesjournals.org/content/vol26/suppl_1/

1. American Diabetes Association. Economic consequences of diabetes mellitus in the U.S. in 1997. Diabetes Care 1998; 21:296-309, 1998.

2. Gu K, Cowie CC, and Harris MI: Diabetes and decline in heart disease mortality in US adults. JAMA 1999; 281:1291-297, 1999.

3. Boyle JP, Honeycutt AA, Narayan KMV, Hoerger TJ, Geiss LS, Chen H, Thompson TJ: Projection of diabetes burden through 2050: Impact of changing demography and disease prevalence in the U.S. Diabetes Care 2001; 24:1936-1940.

4. CDC Cost-effectiveness Group. Cost-effectiveness of intensive glycemic control, intensified hypertension control, and serum cholesterol level reduction for type 2 diabetes. JAMA 2002 287:2542-2551.

5. American Diabetes Association. Standards of Medical Care for Patients with Diabetes. Diabetes Care (Suppl 1), 2002

Adapted with permission from Merz CN, Buse JB, Tuncer D, and TWILLMAN GB. J Am Coll Cardiol 2002 40:1877-81.

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