Heart disease
CVD = Cardiovascular disease
Why discuss heart disease?
When lipodystrophy and metabolic changes associated with combination therapy became more widely recognised, there was an initial concern that these symptoms could increase the risk for heart attack or stoke. This concern was prompted by a series of case reports of heart attacks in HIV-positive men who were too young to be considered as traditionally at high risk.
However, the risk of heart disease may be increased more by HIV than by HIV treatment.
Several large studies have reported results that calm some of these initial fears.
- Benefits of combination therapy still far outweigh the possible slightly increased risk of heart disease for most HIV-positive people
- The SMART study found that using HIV treatment with an undetectable viral load was protective of heart disease compared to not being on treatment or having a detectable viral load.
- The D:A:D study showed a small additional increase in risk of heart disease from each year on protease inhibitor treatment (10%), but not from using NNRTIs. In 2008 D:A:D also reported an increased risk from current or recent use of the nukes abacavir (90%) or ddI (45%).
- People at high risk for heart disease may need to take any additional risk more seriously
- Risk factors for heart disease in HIV-positive people are the same as for people who are HIV-negative
- Making lifestyle changes that minimise risk factors are now strongly recommended as part of a long term plan for managing HIV-positive patients.
There is a lot of information and research about risk factors for heart disease in HIV-negative people. This has often come from very large studies (Framingham, Caerphilly etc) that followed a large group of people for many decades. These studies led to the development of risk calculators that are easy to access online
If you put in your age, gender, cholesterol and triglyceride levels and other risk factors such as smoking, you get your 5-year or 10-year risk of heart disease.
People with high risk factors for heart disease who need HIV treatment, should use HIV drugs that have the least risk of increasing the risk of cardiovascular disease any further, and receive support for lifestyle changes.
Risk factors for heart disease
The following factors increase the risk of heart disease, some of which are fixed and some are modifiable by lifestyle.
Fixed risk factors:
- Older age (men over 45, women over 55)
- Gender (men are at higher risk at the same age)
- Family history of heart disease
Modifiable risk factors:
- Smoking
- High levels of fat in blood – ie high cholesterol and/ or triglyceride levels
- Lack of exercise
- High blood pressure, especially diastolic blood pressure
- High levels of sugar in blood, insulin resistance and diabetes
Symptoms of heart attack or stroke
Symptoms of cardiovascular disease include:
- Shortness of breath
- Fatigue
- Feeling dizzy or light-headed
- Fainting
- Chest pains (that can extend to the shoulders, back, arms, head and jaw)
- Chest pains after exercise or exertion
Additional symptoms for a stroke include:
- Sudden numbness
- Paralysis of the face or limbs, especially affecting just one side of the body
- Difficulty speaking
- Loss of balance or coordination
- Severe headache
- Brief loss of consciousness
If you experience these symptoms, you should seek urgent medical attention.
Rapid treatment after a stroke (within 2-3 hours) can limit permanent brain damage.
D:A:D Study
The D:A:D study is the largest study to look at the risk of heart disease in relation to HIV treatment.
The study collected information from over 33,000 patients from Europe, the US and Israel.
This diversity of patients is one of the study’s strengths. D:A:D found that duration of protease inhibitor-based treatment was related to a small but significant increased risk of heart disease. This was found in different countries and in both men and women.
The link to use of abacavir or ddI has been more controversial as this was the first large study to report this. This risk was seen in people who were currently using, or who had recently used, either of these two drugs. The risk did not continue once these drugs were switched to other treatments.
Relative rate and actual risk
The D:A:D study showed that the relative rate for heart disease increased by around 10% for each year of protease inhibitor treatment, after allowing for other factors such as blood lipids. The impact on the use of abacavir almost doubled the absolute risk.
How these new results affect use of abacavir is likely to become clearer later this year.
How much this affects your individual risk depends on whether you are at a high or low risk to start with. Individualising HIV care will be linked to your other risk factors.
If you have high blood cholesterol for example but no other risk factors, then your absolute risk will still remain low. However, for a 50-year old male smoker who has high cholesterol and is on HIV medication, it is more important to change one or more of these factors.
For someone who has a high risk because of factors that can’t be changed (ie a familiy history of heart disease) then it is more important not to add to these risks by using any HIV drug with this potential side effect.
How to make lifestyle changes
Changing the risk factors for heart disease can have a direct impact on future risk. By implication, this will also make HIV drugs safer to use.
The advice given to the general population is even more important if you are using HIV treatment.
- Stopping smoking is the most important lifestyle change in terms of general health and risk of heart disease. Support groups and other interventions including replacement therapy like nicotine patches are now available on the NHS. The most recent research suggests trying a range of products over the first week or two to cope with nicotine withdrawal such as patches, gum, inhalers and sprays so that you find the ones that work best for you. Your HIV doctor can refer you to specialist services to help you quit.
- Diet changes are other significant changes that can reduce your risk for heart disease.
- Reducing fatty foods can reduce lipids to some extent. Cutting down on salt reduces blood pressure. Eating less processed sugars reduces your risk of developing insulin resistance and diabetes.
- Eat more fruit and vegtables, fish and lean meat and reduce use of processed foods.
- Exercise is the other main modifiable factor. Regular exercise and being more active in your day-to-day life, by walking more and using the lift less, is more important than very vigorous exercise. Any change in level of activity will probably have to start gradually. People who start an exercise programme report benefits in quality of life. This can include increased well-being and energy levels.
Further information
The website for the North Central London Cardiac Network includes detailed guidelines for managing heart disease:
Glossary (heart disease)
Arteries are the blood vessels that take blood from the heart to the lungs.
Veins are blood vessels that delivery blood back to the heart again.
Arrhythmia is the medical terms for a disturbance of the heart’s natural rhythm. Tachycardia refers to when the heart beats too fast. Bradycardia is when the heart beats too slowly.
Atherosclerosis refers to a narrowing or hardening of large and medium sized arteries. The narrowing is caused by a build-up of plaque, and usually takes many years. As the walls of the artery thicken, the heart has to work harder to pump the same amount of blood through a narrower gap.
Cardiovascular refers to the heart and blood vessels.
Cardiovascular disease (CVD) is the general term for disease to the heart and related blood vessels.
Cerebrovascular refers to the blood vessels taking blood to the brain. A blockage that restricts blood to the brain is called a stroke. Strokes can occur when blood vessels in the brain block, or when a clot formed in another part of the body is carried to the brain.
Coronary heart disease (CHD) refers to the three main arteries that supply blood from the heart. A coronary by-pass is a surgical operation to provide a new route for blood to reach the heart when coronary arteries become blocked.
Hypertension is the medical name for high blood pressure (BP). Blood pressure is measured as two numbers ie 120/80. The first number is systolic BP – the pressure when your heart beats. The second number is diastolic BP, which is the pressure when you heart rests between beats.
Target range for BP is usually quoted as 120/80, with interventions sometimes recommended if this is above 130/85 or 140/90, but these are dependent on risk factors for heart disease including your age.
Hypertension increases the risk of a heart attack, particularly when diastolic BP is high.
Hypotension is the medical name for low blood pressure.
Pulmonary hypertension refers to high blood pressure in the arteries taking blood from the heart to the lungs. HIV-positive people are more likely to develop pulmonary hypertension than HIV-negative people.
Myocardial Infarction (MI) is the medical term for ‘heart attack’.
Peripheral arterial disease refers to atherosclerosis in the arteries in the arms or legs.