Focus on Cardiovascular Disease

Managing the Overall Risk of Cardiovascular Disease

Cardiovascular disease (CVD) is the leading cause of death in the United States, killing more Americans each year than the next five leading causes of death combined. It affects one in five Americans, resulting in millions of health care visits and procedures each year (Table 1). And, as the population ages, the incidence of CVD and related health care costs are expected to continue to rise.[1] The ability of a health plan to manage - or preferably prevent - CVD is paramount to the health of its members. Therefore, health plans need to be at the forefront of coordinated, patient-centered cardiovascular medicine.

The indirect costs associated with CVD are also staggering. Employees with CVD may take time from work to address issues concerning their risk factors, symptoms, and coronary events. CVD-related morbidity and mortality among employed Americans is, therefore, associated with a significant loss of productivity in the workplace (Table 2).[1] Employers who are assessing the value of employee health care will want to know what the health plan is doing to manage CVD and, by extension, lost productivity

Health plans and employers are concerned about the burden of CVD. Clearly, there is a gap in the quality of cardiovascular health care that must be addressed, so lives can be saved and quality of life enhanced.

The development of CVD can be silent, often without any obvious signs and symptoms. The first time many people learn they have it may be after a serious event, such as a heart attack or stroke. Many cases of CVD can be prevented, however, by identifying modifiable risk factors and treating or controlling them (Table 3.)[2]

A comprehensive approach to cardiovascular risk assessment and management begins with assessment of overall cardiovascular risk. The concept of overall cardiovascular risk includes the cumulative impact of multiple cardiovascular risk factors, rather than the individual impact of each risk factor alone. The overall cardiovascular risk paradigm was developed in response to findings from the Framingham Heart Study, which revealed that:

• Cardiovascular risk factors tend to cluster[4]
• Multiple risk factors have a multiplicative impact[5]
• Even mild-to-moderate levels of multiple risk factors impart substantial risk[6]

One of the most important issues that health plans and physicians must consider and address is the clustering of cardiovascular risk factors. Numerous studies have found that most individuals with one cardiovascular risk factor have others. [4],[7]-[9] Thus, people with diabetes are far more likely to have hypertension and/or dyslipidemia than the general population.7 Often, patients with dyslipidemia have hypertension, patients with hypertension have dyslipidemia, and patients with diabetes also have hypertension and/or dyslipidemia (Table 4). [8]

Also important for health plans to understand is the link between the number of risk factors and the risk of CVD. The presence of more than one risk factor has a multiplicative impact on the risk of CVD. For example, the Framingham Heart Study showed that cardiovascular risk increases with additional risk factors at any given level of systolic blood pressure (SBP), and that for any number of risk factors present, increasing SBP level increases cardiovascular risk. A 40-year-old male nonsmoker with glucose intolerance, hypertension (SBP of 150 mm Hg), and dyslipidemia (total cholesterol [TC] of 260 mg/dL) has a risk of developing CVD that is 6.2 times greater than that of a similar patient with no glucose intolerance, SBP of 120 mm Hg, TC of 185 mg/dL, and a probability of developing CVD of 15/1,000 (or 1.5%) in eight years (Figure 1). [10]

Figure 1. Multiple Risk Factors Markedly Increase Individual Cardiovascular Risk Risk shown here is compared with the baseline risk for a 40-year-old male nonsmoker with TC of 185 mg/dL, SBP of 120 mm Hg, no glucose intolerance, ECG-LVH negative, and a probability of developing CVD of 15/1000 (or 1.5%) in eight years. Addapted from Kannel WB. Hypertension:Physiopathology and Treatment.1997

Furthermore, when multiple risk factors are present, even mildly or moderately elevated risk factors may substantially increase overall risk of CVD. The Multiple Risk Factor Intervention Trial (MRFIT) evaluated the combined influence of blood pressure, serum cholesterol level, and cigarette smoking on death from coronary heart disease (CHD) in a population of 316,099 men. The trial found that having moderately elevated hypertension and dyslipidemia can impart risk similar to a severe elevation of either condition alone (Figure 2). The risk in patients with moderate hypertension and concomitant dyslipidemia was increased 2.5-fold when smoking was added as a risk factor.[11]

Figure 2. Mild-to-Moderate Risk Factors May Have a Major Impact The Controlling High Blood Pressure measure estimates whether blood pressure was controlled in adults 46-85 years of age with diagnosed hypertension. Adequate control was defined as a blood pressure of 150/90 mm Hg or lower. Both systolic and diastolic pressure must have been under these thresholds in order for the person's blood pressure to be considered controlled.

An analysis of more than 2 million patients in a large managed care organization (MCO) showed that the documented prevalence of dyslipidemia, hypertension, and diabetes was 17.6%, 23.8%, and 6.6% respectively.[12] The presence of multiple risk factors was also observed. Coexisting dyslipidemia and hypertension was documented in 7.4% of patients, while the presence of all three risk factors was documented in 3.7% of patients. However, use of the third National Health and Nutrition Examination Survey (NHANES III) prevalence measurements (which simulate screening of the entire US population) to estimate the actual prevalence in the same managed care population revealed that many people with these risk factors remained undiagnosed. The estimated prevalence of dyslipidemia was 35.6%; of hypertension, 27.6%; and of diabetes, 8.7%. The same was true of patients with multiple risk factors, with the prevalence of coexisting dyslipidemia and hypertension estimated at 12.1%, and the prevalence of three coexisting risk factors estimated at 4.7% (Figure 3).[12]

Figure 3. The Prevalence of Dyslipidemia and Hypertension May Be Greater Than Documented[12] Prevalence study of 2.1 million members of an MCO (aged >=20 years). Criteria from JNC 6* and NCEP ATP+ were applied to computerized databases. Projected prevalence was simulated using NHANES III data. *The Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. +National Cholesterol Education Program third Adule Treatment Panel. Adapted from Shelby et al. Am J Mana Care.in press.

Cultural differences can contribute to differing presentations. For example, Hispanics may be more likely to report primarily physical, rather than emotional, symptoms, as in the case with nervios or ataque de nervios. Symptoms can include headache, trembling, tingling, inability to concentrate, or dizziness, but the underlying issues are related to a vulnerability to life’s problems due to the interaction of past stresses. In one study, major depressive disorder was almost 10 times as prominent in Hispanic patients who had suffered ataques than in those who had not.[8]-[10] A similar pattern of “somatization” has been found among Asian immigrants and refugees.11 The reporting of symptoms may reflect cultural heritage in such a way that the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-Interviewee:) criteria for specific disorders may not apply. As a result, the DSM-IV-TR with text revisions includes, as an Appendix, a description of “culture-bound syndromes,” disorders that are perceived or described in a way specific to a given culture, as well as possible corresponding diagnoses.[9]


 Many Patients Are Not Reaching Treatment Goals

Despite established treatment guidelines, there is still a formidable quality gap in the management of cardiovascular risk factors. For example, although 39.4%, 57%, and 53.0% of hypertensive Hispanics, non-Hispanic blacks, and non-Hispanic whites, respectively, are being treated for their condition, only 11.7%, 23.8%, and 21.6%, respectively, are controlled with their medication. The clinical situation is worse for dyslipidemia. As few as 5.9%, 7.2%, and 9.2% of Hispanics, non-Hispanic blacks, and non-Hispanic whites with dyslipidemia, respectively, are being treated for this abnormality, and only 2.5%, 1.8%, and 2.7%, respectively, are controlled with their medication.[8] And finally, only 45% of adults with diabetes have hemoglobin A1C levels of <7%[13]. Clearly, health plans have a formidable gap to close in the control of these important risk factors.

Health plans can look to national treatment guidelines for hypertension and dyslipidemia treatment goals (Table 5). Management of these cardiovascular risk factors to bring the levels of their members in line with these established goals has been associated with a reduction in cardiovascular complications.[3],[14]

In the next section, Addressing the Quality Gap in Cardiovascular Care, we provide a detailed description of how one plan successfully managed hypertension and dyslipidemia in its members.

Figure 4. Percentage of Patients Achieving JNC 6 Blood Pressure Goal*[15] Results are from a study of 41,417 male and female patients treated for hypertension. The percentage of patients reaching blood pressure treatment goals was highest among patients who had hypertension but not diabetes or dyslipidemia, and lowest among patients with hypertension, dyslipidemia, and diabetes. HTN=hypertension; DYS=dyslipidemia *Goal assigned based on LAST blood pressure measured during 2001; the JNC 6 (rather than JNC 7) goals were used because JNC 7 did not report percentages of patients in each category reaching treatment goal. The major changes from JNC 6 to JNC 7 included a revision of the title of the lowest blood pressure category (optimal and normal, respectively), and the addition of a prehypertension blood pressure category in JNC 7, replacing normal and high-normal from JNC 6. Adapted from Schwartz et. al, presented at American College of Cardiology, 52nd Annual Scientific Session, 2003

The quality gap in the treatment of cardiovascular risk factors is also striking among patients with multiple risk factors. Note, for example, how each additional risk factor decreased the blood pressure control rates in a treatment plan analysis of 41,417 hypertensive patients, of which approximately 47% also had dyslipidemia and/or diabetes mellitus (Figure 4).15 Although patients with multiple conditions were more likely to be receiving multiple antihypertensive drugs compared with patients with hypertension alone, they were significantly less likely to achieve blood pressure goals. The percentage of patients reaching blood pressure treatment goals was highest among patients who had hypertension but not diabetes of dyslipidemia, and lowest among patients with hypertension, dyslipidemia, and diabetes.[15]

Both primary and secondary prevention of CVD require lifestyle changes and the aggressive management of multiple risk factors, such as hypertension, dyslipidemia, and diabetes.[18],[19] However, despite the availability of guidelines that are based on the concept of overall cardiovascular risk (Table 5), hypertension, dyslipidemia, and diabetes remain undiagnosed and uncontrolled in many patients.[8],[15] To reduce the staggering - and rising - burden of CVD1, this gap in health care quality must be addressed.

[1] - American Heart Association. Heart Disease and Stroke Statistics - 2003 Update. Dallas, Tex: American Heart Association; 2002.

[2] - American Heart Association. Risk factors and coronary heart disease. Available at : www.americanheart.org/presenter.jhtml?identifier=4762. Accessed July 24, 2003..

[3] - Chobanian AV, Bakris GL, Black HR, et al. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure: the JNC 7 Report. JAMA. 2003;289-2560-2572.

[4] - Poulter N. Coronary heart disease is a multifactorial disease. Am J Hypertens. 1999;12:92S-95S.

[5] - Kannel WB, Contribution of the Framingham study to preventive cardiology. J AM Coll Cardiol. 1990;15:206-211.

[6] - American Heart Association updates heart attack, stroke prevention guidelines [press release]. July 15, 2002. Available at:www.americanheart.org/presenter.jhtml?identification=3003675. Accessed July 24, 2003.

[7] - Fagot-Campagna A, Rolka DB, Beckles GL, Gregg EW, Narayan KM. Prevalence of lipid abnormalities, awareness and treatment in U.S. adults with diabetes [abstract]. Diabetes. 2000;49(suppl 1):A78-A79. Abstract 318-PP.

[8] - Data on file, Pfizer Inc, New York, NY.

[9] - Kannel WB. Risk stratification in hypertension: new insights from the Framingham study. Am J Hypertens. 2000;13(pt 2):3S-10S.

[10] - Kannel WB. Importance of hypertension as a major risk factor in cardiovascular disease. In: Genest J, Koiw E, Kuchel O, eds. Hypertension: Physiopathology and Treatment. New York, NY: McGraw-Hill Book Company; 1977:888-910.

[11] - Neaton JD, Wentworth D, for the Multiple Risk Factor Intervention Trial Research Group, Serum cholesterol, blood pressure, cigarette smoking, and death from coronary artery disease. Arch Intern Med. 1992;152:56-64.

[12] - Selby JV, Peng T, Karter AJ, et al. High rates of co-occurrence of hypertension, elevated LDL-cholesterol, and diabetes mellitus in a large managed care population. Am J Manag Care. In press.

[13] - National Diabetes Education Program. The link between diabetes and cardiovascular disease. Available at: www.ndep.nih.gov/control/CVD.htm. Accessed June 6, 2003.

[14] - Executive Summary of the Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). Bethesda, Md: National Institutes of Health; 2001. NIH publication 01-3670.

[15] - Schwartz JS, McLaughlin T, Griffis D, Arnold A, Pettit D. Treatment patterns and goal attainment among treated hypertensive patients with and without dyslipidemia and/or diabetes. Poster presented at: American College of Cardiology, 52nd Annual Scientific Session; March 30-April 2, 2003; Chicago Ill.

[16] - American Diabetes Association. Standards of medical care for patients with diabetes mellitus. Diabetes Care. 2003;26(suppl 1):S33-S50.

[17] - HEDIS® 2003 Narrative; 2002.

[18] - Pearson TA, Blair SN, Daniels SR, et al. AHA guidelines for primary prevention of cardiovascular disease and stroke: 2002 update. Circulation. 2002;106:388-391.

[19] - Smith Stephen Covey Jr, Blair SN, Bonow RO, et al. AHA/ACC guidelines for preventing heart attack and death in patients with atherosclerotic cardiovascular disease: 2001 update. Circulation. 2001;104:1577-1579.