Thursday March 27 2014
Young at heart or not?
“People are being urged to find out their "true" heart age in order to cut the risk of heart attacks and strokes,” BBC News reports. Doctors have put together a new risk calculator called JBS3 that can tell you the real “age” of your heart.
Risk calculators for cardiovascular diseases or CVDs (conditions that affect the heart and blood vessels) are nothing new. The “granddaddy” of risk calculators – the Framingham risk calculator – has been available for years.
But this new JBS3 calculator has the benefits of:
- being easily accessible online
- providing what is thought to be an accurate risk estimate of experiencing a serious CVD such as a heart attack or stroke
- unlike previous risk calculators it is of use to younger adults who, while possibly not having a short-term risk of CVD, could be on the route to a stroke or heart attack due to unhealthy lifestyle choices
This new JBS3 calculator was specifically designed to help healthcare practitioners identify and communicate risk of CVDs to the “sizeable number” of people whose risk in the next 10 years is low, but who may be at high risk over their lifetime.
The calculator includes estimates of someone’s “heart age” and the years they can be expected to enjoy without developing cardiovascular disease.
It also shows the benefits that people would experience if they made changes in their lifestyle such as stopping smoking, or reducing blood pressure or cholesterol levels. It also shows the effects of delaying making these changes.
The ultimate aim of the calculator is to empower people to reduce their risk of cardiovascular disease.
It is expected that the JBS3 calculator will become an important component of the NHS Health Check plan – an ongoing programme for adults aged 40 or over.
Who has produced the risk calculator?
The risk calculator has been produced by experts from 11 UK professional societies (the Joint British Societies or JBS) and charities involved with cardiovascular disease (CVD) prevention.
The tool is based on the available scientific evidence and on assumptions where evidence is not available.
It is part of newly updated JBS guidelines on the prevention of cardiovascular disease, called JBS3.
The guidelines have been written for GPs and practitioners to help guide their work with patients, in preventing CVD.
Why is a new calculator needed?
The JBS notes that although CVD deaths have almost halved in the last 40-50 years, cardiovascular disease is still the leading cause of deaths worldwide. This is especially the case as levels of risk factors for CVD, such as obesity and diabetes, are increasing.
They say that currently, prevention strategies target only those at high short term risk (within the next 10 years) of a heart attack or stroke.
They point out that this ignores many individuals – often younger people and women – who may not be at short term risk, but whose family history and lifestyle factors mean they may be at high risk of developing CVD in their lifetime.
There is a growing body of evidence, they say, that CVD develops over a long term with most heart attacks and strokes occurring in people in the “intermediate risk” category.
The new calculator assesses the risk of heart disease and stroke throughout someone’s lifetime, as well as in the short term.
What sort of people is the risk calculator recommended for?
The JBS recommends that the new calculator is used by healthcare professionals for estimating CVD risk for all individuals except those already known to have CVD or specific conditions that put them at high risk, such as diabetes, chronic kidney disease, or a specific genetic condition that leads to high cholesterol.
One of its main aims is to identify the “sizeable” number of people who are at low short term risk but high lifetime risk, of CVD. It aims to help both patients and health professionals better understand cumulative lifetime risk and what can be done to lower it.
What factors does the risk calculator assess and what results does it give?
The calculator assesses established risk factors for cardiovascular disease such as blood pressure, cholesterol levels, smoking status, family history, age and gender. It uses these to calculate not only the risk of CVD within the next 10 years, but over a lifetime. These are displayed in a number of ways that a healthcare professional can use to discuss these figures with their patient:
- A person’s “Heart age”, compared to someone of the same age, gender and ethnicity with optimal risk factors (for example, not smoking and not overweight or obese).
- “Healthy years” – a thermometer image showing how many years an individual can be expected to survive without having a heart attack or stroke.
- An “Outlook screen” showing a graph with the chance of survival without a CVD event.
The tool also enables the healthcare professional to show the patient the potential effect on CVD risk of various lifestyle changes or interventions such as lowering blood pressure, or stopping smoking.
Can you give an example of the figures the calculator might produce?
The press release accompanying the release of the guideline and calculator gives an example of a 35 year old female smoker, with:
- a high systolic blood pressure (the first number in a blood pressure reading) of 160 mm Hg
- a high total cholesterol of 7mmol/l (the recommended level for healthy individuals is 5mmol/l)
- plus a family history of premature CVD
The calculator estimates that the woman would have a “true heart age” of 47 (above her actual age). She could expect to survive to the age of 71 without having a heart attack/stroke. Her 10 year risk would be less than 2%.
The calculator estimates that if this woman stopped smoking, cut her total cholesterol to 4mmol/l and her systolic blood pressure to 130 mm Hg, her heart age would fall to 30 (below her actual age). She could expect to live to the age of 85 before having a heart attack/stroke and more than halve her 10 year risk to less than 0.25%.
How will the risk calculator be used in the NHS?
The JBS3 risk calculator is going to form a key component of the NHS Health Check programme in England aimed at 40-74 year olds. The authors note it is not intended to prompt blanket prescribing of the cholesterol lowering drugs statins and other heart health drugs.
In a related press release the Joint British Societies are quoted as saying “It is important to emphasise that, for the majority, the strong message will be the potential gains from an early and sustained change to a healthier lifestyle rather than prescription of drugs,”.
Lifestyle changes include quitting smoking, achieving a healthy weight through adopting a healthy diet and boosting the amount of regular exercise while curbing sedentary activity.
Can I use the risk calculator?
The JBS3 risk calculator is openly available online. However it has been designed for use by doctors and other healthcare practitioners with their patients. To work, the calculator requires values you may not have access to yourself (such as your cholesterol levels and blood pressure).
While the calculator can give you a relatively accurate risk assessment it is recommended that the results it provides are also assessed by a health professional.
If you are aged 40 or above you can have a free NHS Health Check which will assess your risk of heart disease as well as other chronic diseases such as dementia, stroke and kidney disease.
The JBS3 risk calculator is not appropriate for people who have existing CVD and should only be used with caution in patients with certain high risk conditions such as high blood pressure, diabetes and chronic kidney disease.
Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.