Securing the Benefits of Medical Innovation for Seniors: The Role of Prescription Drugs and Drug Coverage. Cardiovascular Disease - Heart Disease and Stroke

07/01/2002

  • About 950,000 Americans die of cardiovascular disease each year, which amounts to one death every 33 seconds.
  • Eighty-three percent of people who die from coronary heart disease are age 65 or older. (American Heart Association 2001)
  • Seventy-two percent of people who suffer a stroke in a given year are 65 or older. (American Heart Association 2001)
  • New therapies for heart attacks and strokes have reduced the morbidity and improved the mortality in patients experiencing these events.

The Percentage of Persons 65 Years of Age and Over who have had a stroke

The Percentage of Persons 65 Years of Age and Over<br />
			 who have had a stroke

Source: National Health Interview Survey, 2000

Heart disease and stroke—the principal components of cardiovascular diseases—are the first and third leading causes of death in the United States, accounting for more than 40% of deaths. (CDC 2002) However, a consideration of deaths alone understates the burden of cardiovascular disease. About 61 million Americans (almost one fourth of the population) live with this disease. Stroke alone accounts for disability among more than 4 million Americans. Almost 6 million hospitalizations each year are due to cardiovascular disease.

Predictably, strokes and heart attacks have a higher incidence in seniors. High blood pressure and diabetes are chronic conditions that predispose individuals to develop cardiovascular disease. Both diseases have a relatively high prevalence in seniors.

Percentage of Persons 65 Years of Age or Over with Coronary Heart Disease, 2000

Percentage of Persons 65 Years of Age or Over with<br />
			 Coronary Heart Disease, 2000

Note: Coronary heart disease includes coronary heart disease, angina, and heart attack.

Source: National Health Interview Survey

Newer treatments for cardiovascular disease

Recently developed treatment approaches for heart attacks and strokes have reduced the morbidity and improved the mortality in patients experiencing these events. For example, Tissue Plasminogen Activator (t-PA) is a thrombolytic agent, known as a “clot-busting” drug. It can dissolve blood clots, which cause most heart attacks and strokes. The FDA approved the use of t-PA for treatment of some strokes in 1996. The prompt use (within the first three hours) of t-PA following an ischemic stroke has been shown to halt damage and significantly improve recovery. In addition, prompt treatment of stroke victims with t-PA could result in substantial net cost savings to the health care system. (NIH 1995; Fagan 1998) These savings are based on the fact that t-PA-treated stroke patients, because of their decreased disability, leave the hospital sooner and require less rehabilitation and nursing after discharge than do patients who do not receive t-PA.

GP IIb/IIIa inhibitors are another example of newer pharmaceuticals that reduce the risk of atherosclerotic events (myocardial infarction and stroke) in patients with atherosclerosis documented by recent stroke, recent myocardial infarctions, or established peripheral arterial disease. (Sabatine 2000) These drugs inhibit platelet aggregation (platelet blockers), which is a factor in the initiation or evolution of acute cardiovascular or cerebrovascular events. GP IIb/IIIa inhibitors include clopidogrel, eptifibatide, and tirofiban.

The Percentage of Persons 65 Years of Age and Over with Hypertension, 2000

The Percentage of Persons 65 Years of Age and Over<br />
			 with Hypertension, 2000

Note: This represents persons who have been told on two different visits or more that they had hypertension or high blood pressure.

Source: National Health Interview Survey, 2000

In recent years, there have been significant advances in the treatment of chronic conditions, such as hypertension, that place patients at elevated risk for strokes and other cardiovascular diseases. For example, angiotensin II receptor antagonists—losartan (Cozaar®) and valsartan (Diovan®)—represent relatively new therapies for the treatment of hypertension, a primary risk factor for heart attacks and strokes. These drugs are readily available and widely used in the U.S. to treat high blood pressure, and are preferred by many patients and doctors because of their effectiveness and the absence of side effects in many patients. However, they are often not covered in other countries. For example, as a result of formulary restrictions in Ontario and other Canadian provinces, access to these drugs is restricted to patients who have proven that they cannot tolerate other high-blood pressure medications. (Ontario Ministry of Health and Long Term Care 2001) In Australia, although Cozaar® treatment was reimbursed approximately six years ago, the government instituted further cost controls, and as a result the drug is no longer sold in Australia. (Merck & Co. 2002) In New Zealand, only specialists (cardiologists) can initiate therapy with Cozaar®, and then only after the patient has developed congestive heart failure and has failed treatment attempts with at least two kinds of angiotensin converting enzyme (ACE) inhibitors. Diovan® is not approved for coverage in New Zealand. (PHARMAC 2002)

Drugs in the pipeline to treat cardiovascular disease

  • Research is underway on a clot-dissolving drug made from the venom of a pit viper snake. (Sherman 2000)
  • Pharmaceutical approaches to limit brain damage and to aid recovery of stroke victims represent new approaches to treatment. (NIH 2002)
  • A drug that lowers the heart’s need for oxygen may protect the heart muscle from damage during a heart attack. (NIH 2002, PhRMA 2002)
  • Angiogenic therapies to revascularize the heart muscle are being investigated. (NIH 2002)

Advances in medical science have yielded new approaches to the treatment of cardiovascular disease. (Lefkowitz 2001) PhRMA reports that 122 new medicines are in development for cardiovascular diseases in 2002. (PhRMA 2002) Some of these new agents are directed at chronic medical conditions that are risk factors for the development of heart disease, such as high blood pressure or high cholesterol. Other compounds are new treatments for complications of heart disease including congestive heart failure and arrhythmias. For example, B-natriuretic peptide (BNP) is a small protein produced by the heart muscle that improves cardiac function. A recombinant form of BNP was recently approved by the FDA for the treatment of decompensated congestive heart failure. (NIH 2002) Other potential uses of BNP are currently being investigated.

Two broad, complementary strategies are under development, which aim to reduce morbidity from a stroke. One is to restore blood flow to the brain as quickly as possible and another is to limit the damage incurred by a stroke. Similar to t-PA, the venom of a pit viper snake is a clot-dissolving drug. While this drug has not been approved yet, early findings suggest that it helps stroke patients regain their physical and mental abilities, with many patients experiencing full recovery. (Sherman 2000)

The NIH reports that several compounds that may limit brain damage in stroke victims are now being tested in animal models. Scientists are trying to develop “neuroprotective drugs” that prevent strokes from damaging brain cells. Efforts to develop neuroprotective drugs build on very substantial research efforts that are unraveling the complex cascade of harmful events that occur in the brain in the seconds, minutes, and hours following a stroke. Each step in the cascade presents a potential target for drug intervention. Excitotoxicity occurs from excessive release of the normal neurotransmitter glutamate, and, when challenged by stroke, brain cells produce highly reactive and potentially harmful chemicals called “free radicals.” Research is developing drugs that intervene at various stages of excitotoxicity, free radical damage, and other aspects of the stroke-induced cascade of events in the brain. For example, anti-oxidants to prevent free-radical damage are being evaluated. As another example, amapakines are drugs that act by modulating a subclass of nerve cell receptors for a specific neurotransmitter. Excessive release of this neurotransmitter can cause damage in stroke victims. Testing is being conducted to determine if amapakines can prevent brain damage from stroke or help improve learning and memory following stroke. (NIH 2002)

Finally, scientists have been encouraged by recent findings that the adult human brain has a surprising capacity to adapt following disease or injury, even to the extent of making new nerve cells. As a result, researchers are trying to develop drug interventions that enhance the brain’s capacity to repair itself.

View full report

Preview
Download

"innovation.pdf" (pdf, 708.29Kb)

Note: Documents in PDF format require the Adobe Acrobat Reader®. If you experience problems with PDF documents, please download the latest version of the Reader®