- Modifiable cardiovascular risk factors, such as obesity, type 2 diabetes, and smoking, were associated with the buildup of high risk plaque in the major coronary arteries.
- Having a greater number of modifiable risk factors was associated with a greater number of high risk, or vulnerable, plaques.
- High risk plaques are more likely to trigger adverse cardiac events such as heart attacks.
A new study has shed new light on how certain cardiovascular risk factors might alter a person’s risk of adverse cardiac events, such as heart attacks, by noting an association between modifiable risk factors and the buildup of plaques in the coronary arteries
Researchers from Mass General Brigham Heart and Vascular Institute set out to investigate the association between both modifiable and non-modifiable risk factors and the amount and types of plaques found across the three major coronary arteries
Clinical practitioners have long been aware of factors that can influence people’s risk of developing cardiovascular disease
These factors include modifiable ones, which people can change, such as high blood pressure, obesity, and cigarette smoking. They also include non-modifiable factors that people cannot alter, such as age, sex, and a family history of coronary artery disease
While these risk factors are well-established, most research up until now has focused on looking at them individually, or within specific groups of patients
The new study, published in JACC: Advances, took a different approach by looking at all of these risk factors together to see how the number of risk factors present might relate to plaque formation
What did the researchers look at?
The researchers examined optical coherence tomography (OCT) imaging from 131 patients from the Massachusetts General Hospital registry who had not previously received treatment for blocked or narrowed coronary arteries
OCT is an imaging technique using near-infrared light that can provide highly detailed cross-sectional images of blood vessels
Each participant received OCT imaging of their three major coronary arteries. Across all of the patients, this imaging revealed a total of 534 plaques for the researchers to analyze
The researchers then looked to see if there were any associations between the plaques present in the coronary arteries with the risk factors the participants had. They carried out separate analyses looking at modifiable risk factors, non-modifiable risk factors, and total risk factors
What did the researchers discover?
The study authors found that as the number of risk factors increased, so too did the number of plaques visible in the OCT imaging
They also observed a greater number of a particular type of plaque, known as thin-cap fibroatheroma. This type of plaque is known to be a high risk, or vulnerable, plaque type that is more likely than other types to trigger adverse cardiac events like heart attacks
A greater number of risk factors was also associated with a higher number of another type of vulnerable plaque: lipid-rich plaques
Among participants with at least 4 modifiable risk factors, 1 in 2 plaques were thin-cap fibroatheromas, and 4 in 5 were lipid-rich plaques
“The higher the number of vulnerable, or rupture-prone plaques, the greater the chance that one of them will trigger an adverse event,” said senior author Ik-Kyung Jang, MD, in a press release
Modifiable vs. non-modifiable risk factors
The researchers found that it was only an increased number of modifiable risk factors that was associated with a greater spread of these high risk plaques across all three major coronary arteries
Non-modifiable risk factors were associated with more stable plaque types
The modifiable risk factors recorded in the study were:
- high levels of low-density lipoprotein cholesterol
- high blood pressure
- diabetes mellitus
- obesity
- cigarette smoking
Medical News Today asked Dr. Jang why modifiable risk factors might be more associated with the buildup of vulnerable plaques than non-modifiable risk factors
“We believe that the association between modifiable risk factors and plaque vulnerability is largely mediated by inflammation,” he said. “All five modifiable risk factors—dyslipidemia, hypertension, diabetes, obesity, and smoking—are known to promote vascular inflammation
“In contrast, non-modifiable risk factors, such as age, sex, and family history, may primarily contribute to the gradual progression of atherosclerosis through pathways less directly driven by inflammation,” he added
What comes next?
“The natural next step is to test, in a prospective study, whether aggressive management of modifiable risk factors can reduce plaque vulnerability,” Dr. Yang told MNT
The researchers acknowledge that the limitations of this study mean that more research is needed before their findings can be generalized to a wider population
The data they analyzed for the study came from a specific pool of hospital patients, who had yet to receive certain types of treatment and who were able to receive OCT imaging. As a result, the study authors say these present findings are only suitable for interpretation among a similar patient population
In order to generalize these findings, the authors suggest that research involving larger groups of people that include people who have received treatment for blocked arteries will be required
Until then, they conclude that their findings underline the importance of targeting modifiable risk factors to help prevent heart attacks
“Our findings highlight the importance of early, intensive and sustained interventions to control the modifiable risk factors and prevent future events,” said Dr. Jang in the press release
