Evaluation of international guidelines: Recommendations for people with coronary heart disease

German disease management programmes for people with coronary heart disease are essentially in line with recommendations made in international guidelines. A few additions could be made, for example, about weight reduction and flu vaccination.

Coronary heart disease (CHD), sometimes also called coronary artery disease (CAD), is a chronic condition. It arises when the blood vessels around the heart which supply the heart muscle with oxygen (coronary arteries) become narrow. People who have CHD have hardened coronary arteries. This is known as "arteriosclerosis". Arteriosclerosis can develop when fats and other substances in the blood accumulate in a damaged site within the blood vessel wall, and the vessel becomes increasingly narrow. Fatty deposits like this ("plaques") build up in the blood vessels of most people at some point in their lives. In severe cases of CHD, the narrowed coronary arteries may no longer be able to supply the heart with enough oxygen. This kind of blood supply deficiency is known as "ischaemia".

The main symptoms of coronary heart disease are sudden chest pains which can last anything between a few seconds and several minutes. The medical name for this is angina pectoris, which means "tight chest". Along with the pain, there is a feeling of tightness and anxiety. The pain may spread to the back of the neck, the back, arms or jaw.

Specialists differentiate between stable and unstable angina pectoris. In the stable form, symptoms usually only arise during or after physical exercise, like climbing stairs, and then disappear again.
In the instable form of angina pectoris, which is much less common, symptoms already arise following very light physical activity or even when the person is resting. Unlike the stable form, instable angina pectoris poses an immediate threat: the person is in danger of having a heart attack.

Heart attacks (myocardial infarctions) may be caused by coronary heart disease and can be life-threatening. They occur when a coronary artery suddenly becomes so narrow that part of the heart muscle can no longer be supplied with oxygen. If it is not treated in time, part of the muscle tissue dies. Depending on the extent of damage, the heart muscle is permanently weakened, and the heart can no longer work properly. The likelihood of surviving a heart attack has greatly increased over the years: in countries like Germany, about 3 out of 4 people survive a heart attack.

It is not clear exactly how many people have coronary heart disease in Germany. However, there are estimates of the number of people who have heart attacks: every year, about 1 to 2 out of 100 women between the ages of 25 and 74 have a heart attack (between 1% and 2%). Men in the same age group have a slightly higher risk: about 4 out of every 100 men have a heart attack (4%). However, the risk of CHD and possible complications can vary greatly from person to person. The main risk factors are believed to be age, gender, smoking, having diabetes, being overweight and having high blood pressure. Also, a lot of people who have CHD have high cholesterol levels. But there has not been enough research to say what influence high blood cholesterol levels alone may have.

CHD treatment aims to reduce the symptoms of angina pectoris, as well as to prevent heart failure (cardiac insufficiency) and heart attacks. Typical strategies include dietary changes, doing more exercise and giving up smoking. This is usually accompanied by medication. If the condition is serious, surgery is often performed to try to widen the coronary arteries.

Structured disease management programmes

From 2002, people in Germany with CHD have had the option of joining a so-called disease management programme (DMP) offered by state health insurance funds. DMPs, or structured treatment programmes, aim to ensure that people with certain chronic illnesses get the best treatment possible. This could be achieved through, for example, regular doctor's appointments, individual treatment plans and patient education courses. You can read more about DMPs here.

Doctors who participate in a DMP have to follow certain quality criteria and defined treatment plans. In Germany, the Federal Joint Committee (G-BA) determines what requirements a disease management programme has to fulfil and what medical treatments it should include. The Federal Joint Committee is the national decision-making body of the self-governing body of doctors, dentists, psychotherapists, hospitals and health insurance funds in Germany. One important requirement is that the treatment offered should ideally comply with "evidence-based guidelines". Guidelines are a kind of decision aid for doctors and patients. They aim to ensure that patients have the best possible quality-assured treatment. "Evidence-based" means that the guidelines are based on the results of reliable scientific studies, particularly so-called randomised controlled trials.

Medical knowledge is constantly growing, so recommendations for DMPs have to be regularly updated. For this reason, the Federal Joint Committee commissioned the German Institute for Quality and Efficiency in Health Care (IQWiG) to compare the recommendations for the coronary heart disease DMP with current international guidelines, and to point out any changes that may be needed. Together with researchers from the Berlin Institute of Technology, the IQWiG systematically evaluated 21 clinical guidelines from different countries. The Federal Joint Committee took the results of this evaluation into consideration when discussing possible changes to be made to the recommendations for the coronary heart disease DMP.

The results

The researchers found that the recommendations for the coronary heart disease DMP in Germany were generally in line with the current German and international guidelines. However, they suggested that further analysis of the benefits and harms of some treatments could be worthwhile. For example, strategies like losing weight and quitting smoking are more frequently recommended for people with CHD nowadays. Also, two of the guidelines recommend that CHD patients be vaccinated against influenza.

The researchers also suggested that it would be a good idea to update the recommendations for the DMP concerning certain medications and surgical procedures. For example, some guidelines have changed their recommendations about the use of statins (cholesterol-lowering drugs), and about the most appropriate time to consider procedures to widen the coronary arteries or bypass surgery. Another more recent development is that some guidelines emphasise the risks of hormone therapy in women with menopause symptoms.

In our "Heart and circulation" topic area you can read more about the research on cardiovascular diseases and find out what the signs of a heart attack are.

© IQWiG (Institute for Quality and Efficiency in Health Care)