New cardiovascular risk marker identified in older women
A study from Karolinska Institutet reveals that low levels of anti-phosphorylcholine antibodies may indicate increased risk of heart disease in older women, potentially paving the way for improved risk assessment and preventive strategies.
Professor Johan Frostegård, Head of the Immunology and Chronic Disease Unit at the Institute of Environmental Medicine, Karolinska Institutet
Low levels of natural antibody linked to higher cardiovascular risk
Researchers at Karolinska Institutet have uncovered a potential new risk marker for cardiovascular disease in women. The study, published in the Journal of the American College of Cardiology on 2 October 2024, demonstrates an association between low levels of an anti-inflammatory antibody and an increased risk of heart attack and coronary heart disease in older women.
The research focused on antibodies to phosphorylcholine, known as anti-PC, which have previously been shown to have protective effects against atherosclerosis in men. This new study extends these findings to women, addressing a critical gap in cardiovascular research.
Study details and findings
The investigation utilised data from the Swedish Mammography Cohort (SMC), following 932 women with an average age of 66 years over a 16-year period. During this time, 113 women developed cardiovascular disease. The results revealed that women with high levels of the anti-PC antibody had a 25 percent lower risk of coronary heart disease and heart attack compared to those with lower levels.
Professor Johan Frostegård, Head of the Immunology and Chronic Disease Unit at the Institute of Environmental Medicine, Karolinska Institutet, explained the significance of the findings: “We can show that a low level of the natural antibody to phosphorylcholine can be used as a risk marker for cardiovascular disease also in women, independent of previously known risk factors. We have previously shown that the antibody has an anti-inflammatory effect, which means that it protects against atherosclerosis, which is a chronic inflammation of the vessel wall.”
Implications for cardiovascular risk assessment
The identification of anti-PC levels as a potential risk marker could have significant implications for cardiovascular risk assessment in women. Historically, research on women’s heart health has been underrepresented, despite cardiovascular disease being the leading cause of death for both women and men in Sweden.
Women typically develop cardiovascular disease later in life than men and often present with different risk factors, including high blood pressure, diabetes, and heart failure. The addition of anti-PC levels to the risk assessment toolkit could provide a more comprehensive understanding of an individual woman’s cardiovascular risk profile.
Future research directions
While the study demonstrates a clear association between anti-PC levels and cardiovascular risk, further research is needed to establish specific threshold levels for clinical use. Professor Frostegård highlighted this as a key area for future investigation: “We now need to go further to determine what level of anti-PC can be used as a risk level in a similar way to the levels found for high blood pressure, for example. We are now working on an even larger study that includes both men and women where we hope to establish such a level.”
Potential for therapeutic interventions
The researchers are optimistic about the potential therapeutic applications of their findings. One avenue being explored is the development of a vaccine against atherosclerosis that could raise anti-PC levels in individuals identified as having dangerously low levels.
This approach could offer a novel preventive strategy for cardiovascular disease, particularly in older women who may be at higher risk due to low anti-PC levels. However, it is important to note that such interventions are still in the conceptual stage and would require extensive further research and clinical trials before becoming available.
Study limitations and future considerations
As with all observational studies, this research cannot establish causality between anti-PC levels and cardiovascular risk. Additionally, while the study followed a substantial cohort over a 16-year period, larger studies incorporating more diverse populations may be necessary to confirm and generalise the findings.
The researchers also acknowledge that determining a clinically relevant threshold for “low” anti-PC levels will be crucial for translating these findings into practical risk assessment tools. The ongoing larger study mentioned by Professor Frostegård aims to address this issue.
Conclusion
This study represents a significant step forward in understanding cardiovascular risk factors specific to women, particularly in older age groups. By identifying anti-PC levels as a potential independent risk marker, the research opens new avenues for personalised risk assessment and preventive strategies in cardiovascular medicine.
Reference:
Frostegård, J., Åkesson, A., Helte, E., et. al. (2024). Antibodies against phosphorylcholine in prediction of cardiovascular disease among women: a population-based prospective cohort study. Journal of the American College of Cardiology. Published online October 2, 2024.
