Wouldn’t it be ever so useful if we could predict the onset of a debilitating or fatal cardiovascular disease? If this were the case, we could work to prevent them. While we cannot predict future events with absolute certainty, the advent of cardiovascular disease (CVD) risk scores (like the Framingham Risk Score) helps us assess the probability of experiencing an adverse cardiac event. Before we can dive into these powerful metrics and their utility, we should discuss the general function and nature of the human cardiovascular system as it currently stands in evolutionary time.
Our bodies are a mosaic of complex and interconnected organ systems that work in conjunction to carry out many ongoing processes, maintain homeostasis and ultimately a healthy human life. One vital organ system that exhibits this interactive nature with other organ systems is our cardiovascular (or circulatory) system. Through coordination with other organ systems, the cardiovascular system carries out its laundry list of tasks. For instance, our cardiovascular system corresponds with our respiratory, endocrine, and immune systems respectively to transport oxygen, hormones, and white blood cells to various parts of the body as needed. The cardiovascular system also works to bring the waste products of cells (such as carbon dioxide) to the lungs and kidneys where they can be disposed. Even from this preliminary understanding of the cardiovascular system, it is readily apparent that the cardiovascular system and its health is very important.
The cardiovascular system acts as a type of plumbing system in our body, similarly to the domestic plumbing systems of our homes. To stretch this analogy out, consider a plumbing system with a central pump that propels water into a parallel arrangement of pipes that supply different parts of the house. This makes sense since multiple parts of the house may need access to water at the same time, right? These plumbing systems also facilitate local control of water pressure and availability in different parts of the house using faucets and taps. The plumbing system that is our cardiovascular system has the heart as its central pump and propels blood through a system of blood vessels that are arranged in parallel (for the most part) so that each organ system has its own access to blood flow. Furthermore, our blood vessels can constrict (get smaller) or dilate (get bigger) to control the pressure and availability of blood and its contents in certain areas of the body and provide the cardiovascular system its own form of regional control.
What are risk factors and what role do they play?
Carrying our analogy forward, if we were assessing the overall health and sustainability of our domestic plumbing system, we would have to be aware of the “risk factors” that determine the likelihood of encountering any plumbing issues in the future. For example, one risk factor that may impact the health of my domestic plumbing system is the climate in my area. Colder climates might negatively affect the pipes and make them brittle and more susceptible to breaking. Similarly, assessing the future of our cardiovascular health also involves the consideration of many risk factors and how they could negatively impact the system’s health. Risk factors are specific variables that increase (and thus determine) a person’s chances of developing cardiovascular disease.
The list of CVD risk factors include high blood pressure, high cholesterol levels, chronological age, smoking habits, diabetes, sedentary lifestyle, family history of CVD, and being overweight. From the length of the list we can see that there are many variables that may determine the future of someone’s health. Each of the listed risk factors do not equally increase the risk of CVD. To make sense of these risk factors and determine their exact effect we need to make use of some metric that neatly and concisely conveys the risk of developing CVD given a specific list of risk factors. Here is where CVD risk scores can help. By taking an individual’s different risk factors into account, you are able to generate a corresponding score that usually indicates whether there is a mild, moderate, or severe risk of developing cardiovascular disease in the following decade. One important thing to note is that the term CVD refers to a range of different diseases that affect the cardiovascular system. So initially, there were separate risk score algorithms used to assess the risk of specific cardiovascular diseases such as heart failure, cerebrovascular disease (strokes), and coronary heart disease. Each of these risk scores made use of their associated risk factors to determine the likelihood of an individual experiencing each specific cardiovascular disease. After a while, the highly influential Framingham risk function was used to generate a single value to predict the risk of developing any subset of CVD [1].
What exactly is a CVD risk score?
If you’re wondering how these risk score algorithms are developed or used, it might help for us to focus on the Framingham risk score developed from the Framingham Heart Study. The Framingham Heart Study began in 1948 and followed a cohort of about 8491 participants (across 3 generations) in Massachusetts to study the development of CVD in these people and understand how each person’s list of risk factors affected their outcome [1].
From this data they formed an algorithm/formula that appropriately indicates the risk of developing CVD and its constituents when given a specific list of risk factors. What makes the Framingham study special is that their risk score algorithm gives us an indication of the probability that an individual will experience any part of CVD in the following decade. Furthermore, since its advent and modifications in 2008 the Framingham risk assessment tool has become a validated way of predicting CVD risk in patients with no current symptoms [2].
The utility of these CVD risk scores is that our primary care physicians can use them to assess an individual patient’s risk of developing any component of CVD such as stroke, heart failure, heart attack and treat the risk factors involved such as high blood pressure, and cholesterol. In summary these risk scores asses your current lifestyle and cardiovascular health and allow you and your physician to develop and implement a plan to improve your cardiovascular health as needed. This plan can include preventative drugs and/or lifestyle changes like an exercise plan, a specific diet plan, and strategies to quit or reduce smoking habits.
When it comes to getting your own CVD risk score and interpreting its meaning, this process can largely be done independently with Framingham risk score calculators online. All you need to operate the calculator is information about your age, biological sex, smoking habits, cholesterol levels and blood pressure. While some of this information requires some basic bloodwork, most blood testing labs don’t even require a physician appointment for scheduling. There are also mobile services that will pick up individuals from making informed lifestyle decisions based on their risk of developing CVD are being broken and the incentive to act wisely is extremely prevalent.
Once you have all the information for an online CVD risk score calculator, you will receive immediate results that display your risk score as a percentage. This percentage represents the likelihood that you will develop some form of CVD in the coming decade. The percentages are classified as low, moderate or high risks. Values less than 10% represent a low risk. values from 10% to 19% represent a moderate risk and values above 20% represent a high risk [2]. Whatever your CVD risk score is, it is always important to consult a physician to get a more complete understanding of your situation. Higher risk scores are a cause for concern and individuals with these scores have benefitted from consultations and physician determined treatment.
The world of science and medicine has created and validated an incredibly powerful tool (CVD Risk Score) that is easily accessible to most of us. This tool will help us get ahead of the curve in the struggle against cardiovascular diseases. Due to its accessibility and public use, we desperately need to take advantage of these risk assessments as CVD continues to be one of the leading causes of death in North America and many other parts of the world.
Author: Nithin Menon
References
D’Agostino, R. B., Vasan, R. S., Pencina, M. J., Wolf, P. A., Cobain, M., Massaro, J. M., & Kannel, W. B. (2008). General cardiovascular risk profile for use in primary care. Circulation, 117(6), 743–753. https://doi.org/10.1161/circulationaha.107.699579
Framingham heart study cardiovascular disease 10-year risk score clinical classification. (2020). Definitions. https://doi.org/10.32388/tj9mf7
JP Stroke Foundation 
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