Heart disease

CVD = Cardiovascular disease (cardio=heart; vascular=veins and arteries); CHD = coronary heart disease.

Why discuss heart disease?

When lipodystrophy and metabolic changes associated with combination therapy became more widely recognised, there was a concern that these symptoms could increase the risk for heart attack or stroke.

This is because increased levels of blood lipids can lead to blocking blood vessels (atherosclerosis) and are a well-established risk factor for heart disease.

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 slight 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 reported a small additional increase in risk of heart disease from each year on some 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 or ddI.
• 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 are least likely to increase the risk of cardiovascular disease any further. Support for lifestyle changes should also be provided.

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.

It has collected information from over 33,000 patients from Europe, the US and Israel for more than eight years.

This diversity of patients is one of the study’s strengths. D:A:D found that some HIV drugs are related to a small but significant increased risk of heart disease. This was found in different countries and in both men and women.

These drugs include recent use of abacavir, ddI and cumulative use (from each year) of abacavir, indinavir and lopinavir/r (Kaletra).

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 much this affects your individual risk depends on your other risks factors.

If you have high blood cholesterol for example but no other risk factors, then your absolute risk will still remain low. However, for example, for a 50-year old male smoker who has high cholesterol and is on HIV medication, it is more important to reduce and limit one or more of these factors. This is because each risk factor (like smoking or high blood pressure etc) is added up to get the combined risk score mentioned above.

For someone who has a high risk because of factors that can’t be changed (ie a family 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 can significantly 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 vegetables, 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.

The website for the North Central London Cardiac Network includes detailed guidelines for managing heart disease:

North Central London Cardiac Network