Researchers at UCL have tested a new scoring system to measure the risk of stroke in patients with narrowed arteries due to atherosclerosis, which could prevent unnecessary surgeries and stents.
Atherosclerosis is a condition where the blood vessels become narrowed and hardened due to the buildup of plaque, including in the carotid arteries, which carry blood from the heart to the brain. Atherosclerosis can lead to serious health problems like strokes and heart attacks.
Atherosclerosis is a very common condition that can affect anyone, particularly those over the age of 65, smokers and people with a high cholesterol, hypertension or family history of heart or circulatory diseases. It is estimated that atherosclerosis affecting the carotid artery causes up to 20% of strokes.
Currently, many patients undergo surgery or stenting to prevent strokes resulting from atherosclerosis. However, these procedures also carry risks of causing strokes and other serious complications at the time of the intervention.
In the new study, published in The Lancet Neurology and in collaboration with colleagues at the Amsterdam University Medical Centre and the University of Basel, researchers found that using the Carotid Artery Risk (CAR) scoring system can offer a safer alternative, by identifying patients who can be effectively treated with a combination of medications and lifestyle changes tailored to their individual risk factors (otherwise known as optimised medical therapy).
The CAR system was developed by researchers at UCL and the University of Oxford.
Senior author, Emeritus Professor Martin Brown (UCL Queen Square Institute of Neurology), said: "While further follow-up and additional trials are needed to confirm these findings, we recommend using the CAR score to identify patients with carotid narrowing who can be managed with optimised medical therapy alone.
"This approach emphasises personal assessment and intensive treatment of vascular risk factors, potentially sparing many patients from the discomfort and risks of carotid surgery or stenting.
"Additionally, this method could lead to substantial cost savings for health services."
The new research paper, which was partly funded by the Stroke Association, evaluated the effectiveness of the CAR score by testing it in a randomised clinical trial involving 428 patients across 30 centres in the UK, Europe and Canada.
All patients involved in the trial were over the age of 18 and had a significant narrowing of their carotid arteries, which was picked up before it had caused symptoms or after it had caused a minor stroke.
Those with symptoms were selected using their CAR score - which takes into account factors such as the percentage of narrowing in the carotid artery and medical history - to determine who had a low to intermediate risk of stroke over the next five years and could be included in the trial. Patients with a high score were not suitable for the trial and were recommended immediate surgery or stenting.
The patients in the trial were then divided into two groups, with one group receiving optimised medical therapy alone, and the other group receiving both optimised medical therapy and additional carotid surgery or stenting.
Optimised medical therapy included a low cholesterol diet, target-adjusted cholesterol-lowering medication, treatment to lower blood pressure, antithrombotic therapy (a treatment that helps prevent blood clots from forming or growing), and regular checks to adjust the medication as necessary.
The patients were monitored through regular visits, telephone calls, and brain scans to detect strokes.
The researchers found that, over the first two years, patients in the trial who were treated with optimised medical therapy alone had very low rates of recurrent strokes and heart attacks. Those who underwent additional surgery or stenting did not experience significant benefits, considering the associated risks of these procedures.
Dr Louise Flanagan, Head of Research at the Stroke Association, said: "Atherosclerosis is a common condition, and a major risk factor for heart disease and stroke. Whilst medical therapy is the first line of treatment, many of those who have medical therapy then need surgery or stenting which can lead to complications including an increased risk of stroke, and other unpleasant side effects.
"The CAR risk score offers the opportunity to take away the downsides of surgery and stenting by using medical therapy alone as well as combining medical therapy with surgery. The Stroke Association is pleased to have funded this trial which indicates that some people with atherosclerosis could see the same benefits from medication and lifestyle changes that previously required surgery.
"The medical therapies used to reduce the risk of stroke from atherosclerosis work by treating risk factors for stroke, including high cholesterol and raised blood pressure, which we are putting at the heart of our recommendations for the Government's 10 Year Health Plan.
"Whilst we welcome the results of this study, we note the need for more research to confirm or refute these findings, so we look forward to further developments."
The research was funded in the UK by the National Institute for Health and Care Research (NIHR), the Stroke Association and the Leeds Neurology Foundation, and in Europe by the Swiss National Science Foundation and the Dutch Organisation for Knowledge and Innovation in Health, Healthcare and Well-Being.
