Learn the ABC of heart disease

Cardiovascular diseases – heart disease and stroke – are the leading causes of death and disability in developed countries. But fortunately, there are many things we can do to lower our risk.

The first step is having an individual risk assessment. Based on many long-term studies of apparently healthy people, the most important risk factors that lead to the development of cardiovascular disease are elevations in blood pressure and blood fats such as LDL-cholesterol and triglycerides, high levels of blood sugar (leading to diabetes), and, very importantly, cigarette smoking.

The Framingham Risk Score is commonly used in the United States and the HeartScore is often used in Europe to estimate an individual’s risk of having a heart attack or cardiac death in the next decade. Both risk prediction models take into account the person’s age, gender, and the aforementioned risk factors to calculate the individual’s risk. With the Framingham Risk Score, an individual whose estimated risk of a heart attack over the next ten years is less than 10 per cent is considered to be at “low risk,” while an estimate of 10 to 20 per cent is considered “intermediate risk” and an estimate greater than or equal to 20 per cent is considered “high risk”.

While valuable, this way of estimating an individual’s risk is not perfect because these models are driven mainly by chronological age rather than biological age, namely the health of the person’s coronary arteries. New data has become available recently that, in the near future, may lead to new guidelines that help us to provide more individualised risk assessments.

The cornerstone of prevention for all individuals is to adopt a healthy lifestyle

Meanwhile, the cornerstone of prevention for all individuals is to adopt a healthy lifestyle. A large, multi-centre study led by Johns Hopkins researchers published in June found a significant link between lifestyle factors and heart health, adding even more evidence in support of regular exercise (about 30 minutes each day), eating a Mediterranean-style diet of vegetables, fruit, whole grains and fish, keeping a normal weight and, most importantly, not smoking.

In our study, we found that adopting those four lifestyle behaviours protected against cardiovascular disease, as well as the early build-up of calcium deposits in heart arteries, and reduced the chance of death from all causes by 80 per cent over an eight-year period.

However, even with the adoption of healthy lifestyle choices, some individuals may eventually need medications to lower their risk.

Men and women, who are at intermediate or high risk, may benefit from taking an aspirin daily. Aspirin prevents heart attacks and strokes by decreasing the development of blood clots. But aspirin may cause bleeding in the gastrointestinal tract or an upset stomach. As a result, we generally only prescribe a daily, low dose of aspirin if a person’s projected risk of a cardiovascular event, such as a heart attack, is above a certain threshold, such as a 10 per cent risk over the next decade.

We often prescribe cholesterol-lowering medications known as statins to adults who clearly have some hardening of their arteries from plaque build-up, as well as those with diabetes, a markedly elevated level of the “bad” LDL-cholesterol or a higher risk of a cardiovascular event for other reasons.

In order to better personalise a person’s cardiovascular risk, a physician may recommend an imaging test, such as a computed tomography (CT) scan, to assess the amount of coronary calcium in heart arteries. Also, a specialised ultrasound test of the neck is sometimes useful to look for plaque in the carotid arteries and measure the thickness of the neck arteries. Our studies have shown that the results of these imaging tests can better predict true risk.

It is important for all adults to remember that they can significantly reduce their lifetime risk of a heart attack, stroke or development of clogged arteries by improving their lifestyle habits, and talking to their healthcare providers about selective use of statin therapy and aspirin.