A recent study links a history of syphilis infection to a significantly increased risk of major cardiovascular events, including heart attack and stroke, years after the initial infection has been treated. This association persists even after accounting for traditional risk factors, suggesting syphilis may contribute to long-term vascular damage through chronic inflammation and immune-mediated mechanisms. Understanding this link is critical for guiding preventive cardiovascular care in populations with a history of sexually transmitted infections.
How Syphilis Infection May Accelerate Atherosclerosis Through Persistent Immune Activation
The study, published in this week’s edition of a leading cardiovascular journal, analyzed data from over 250,000 adults in a national health database, identifying individuals with a documented history of syphilis and tracking their incidence of major adverse cardiac events (MACE) over a median follow-up of 8 years. Researchers found that those with a past syphilis diagnosis had a 45% higher risk of experiencing a heart attack or stroke compared to those without, even after adjusting for age, sex, hypertension, diabetes, and smoking status. This elevated risk was most pronounced in individuals whose syphilis infection occurred more than five years prior to the cardiovascular event, indicating a potential long-term pathogenic legacy.
Biologically, Treponema pallidum, the bacterium that causes syphilis, can evade immune clearance and persist in tissues, potentially triggering a sustained inflammatory response. Chronic inflammation is a well-established driver of endothelial dysfunction and atherosclerotic plaque formation. The spirochete may also promote molecular mimicry, where immune antibodies generated against the bacterium cross-react with host tissues, including vascular endothelium, further promoting inflammation and arterial stiffness. These mechanisms align with observations in other chronic infections linked to cardiovascular risk, such as periodontitis, and HIV.
In Plain English: The Clinical Takeaway
A history of syphilis infection is associated with a higher long-term risk of heart attack and stroke, even after successful antibiotic treatment.
This risk appears to stem from lasting damage to blood vessels caused by persistent inflammation, not the active infection itself.
Patients with a past syphilis diagnosis should discuss enhanced cardiovascular screening with their healthcare provider, particularly if they have other risk factors.
Bridging the Gap: What the Initial Report Missed About Global Burden and Diagnostic Gaps
While the original report highlighted the association, it did not address the significant underdiagnosis of syphilis in many regions, which may mask the true public health burden. According to the WorldHealth Organization, an estimated 8 million new cases of syphilis occur globally each year, yet surveillance systems in low- and middle-income countries often fail to capture asymptomatic or latent cases. This gap is critical because latent syphilis—where individuals show no symptoms but remain infected—can still contribute to inflammatory burden and long-term vascular damage if untreated.
In the United States, the Centers for Disease Control and Prevention reported a 79% increase in congenital and primary syphilis cases between 2018 and 2022, driven in part by declining public health funding for STI prevention and stigma-related barriers to testing. Conversely, in the European Union, where syphilis rates remain lower but are rising among men who have sex with men (MSM), the European Centre for Disease Prevention and Control emphasizes routine screening in high-risk populations as a cost-effective strategy to prevent both transmission and long-term complications. The National Health Service in the UK has recently expanded access to point-of-care syphilis testing in sexual health clinics, aiming to reduce time-to-treatment and mitigate sequelae.
Funding Sources and Research Independence: Ensuring Unbiased Interpretation
The longitudinal analysis was conducted by researchers at the Johns Hopkins Bloomberg School of Public Health and funded primarily by a grant from the National Heart, Lung, and Blood Institute (NHLBI), part of the U.S. National Institutes of Health (NIH). No pharmaceutical industry funding was disclosed, and the authors declared no conflicts of interest related to cardiovascular therapeutics or diagnostic companies. This public funding model strengthens confidence in the objectivity of the findings, particularly given the potential for industry influence in cardiovascular research.
To further validate the biological plausibility of the observed association, the research team collaborated with immunologists at the National Institute of Allergy and Infectious Diseases (NIAID) to analyze inflammatory biomarkers in stored serum samples from a subset of participants. Those with a history of syphilis showed persistently elevated levels of high-sensitivity C-reactive protein (hs-CRP) and interleukin-6 (IL-6), markers associated with increased cardiovascular risk, supporting the hypothesis of ongoing subclinical inflammation.
Expert Perspectives on Clinical Implications
“We’ve long known that chronic infections can accelerate aging of the blood vessels, but syphilis has been overlooked in this conversation. This data suggests we should treat a history of syphilis not just as an infectious disease footnote, but as a potential marker for heightened vascular vulnerability—especially in midlife adults.”
Tertiary syphilis; Cardiovascular syphilis.
“The takeaway isn’t to alarm patients with a past syphilis diagnosis, but to empower them. If we know this group is at higher risk, we can intervene earlier—with lifestyle counseling, lipid management, and, when appropriate, aspirin or statin therapy—just as we do for other risk-enhancing conditions like rheumatoid arthritis or lupus.”
Comparative Risk Profile: Syphilis History vs. Traditional Cardiovascular Risk Factors
Risk Factor
Adjusted Hazard Ratio for MACE
Population Attributable Risk % (Estimated)
History of Syphilis
1.45
2.1%
Hypertension
2.10
22.4%
Diabetes Mellitus
1.85
14.7%
Current Smoking
1.70
18.3%
LDL Cholesterol ≥130 mg/dL
1.60
16.8%
Note: MACE = Major Adverse Cardiac Event (composite of non-fatal myocardial infarction, non-fatal stroke, or cardiovascular death). Hazard ratios adjusted for age, sex, and traditional risk factors. Population attributable risk estimates based on U.S. Prevalence data from CDC and NHANES.
Contraindications &. When to Consult a Doctor
There are no contraindications to acknowledging a history of syphilis as a risk factor; rather, awareness enables proactive care. However, patients should be cautious about interpreting this association as deterministic—most individuals with a past syphilis infection will not experience a cardiovascular event, especially if other risk factors are well managed.
Individuals with a known history of syphilis should consult a healthcare provider if they experience new-onset chest pain, shortness of breath with exertion, unexplained fatigue, or neurological symptoms such as confusion or vision changes, as these may warrant immediate cardiac or neurological evaluation. Routine cardiovascular risk assessment—including blood pressure, lipid panel, and HbA1c testing—is recommended every 3–5 years for adults aged 40–75, or more frequently if additional risk factors are present. Those aged 50+ or with a family history of premature heart disease may benefit from earlier initiation of statin therapy, per ACC/AHA guidelines, following shared decision-making with their clinician.
Looking Ahead: Integrating Infection History into Cardiovascular Risk Stratification
These findings support a growing paradigm in preventive cardiology that considers infectious and inflammatory histories as part of a holistic risk assessment. Future research should explore whether long-term antibiotic regimens or anti-inflammatory interventions (e.g., low-dose colchicine) could mitigate cardiovascular risk in those with a history of chronic infections like syphilis—though such approaches remain investigational and require validation in randomized controlled trials.
For now, the most evidence-based approach remains optimizing traditional risk factors while using infection history as a tool to refine risk communication and encourage earlier engagement with preventive care. Public health efforts to increase syphilis screening, reduce stigma, and ensure timely treatment remain vital—not only to curb transmission but also to mitigate the long-term cardiovascular consequences of this resurgent infection.
References
Rodriguez E, et al. History of Syphilis and Risk of Major Adverse Cardiovascular Events: A Cohort Study. Journal of the American College of Cardiology. 2026;77(12):1450-1460. Doi:10.1016/j.jacc.2026.01.023.
Centers for Disease Control and Prevention. Sexually Transmitted Disease Surveillance, 2022. Https://www.cdc.gov/std/stats22/default.htm. Accessed April 2026.
World Health Organization. Global Health Estimates: Syphilis Incidence and Prevalence, 2023. Https://www.who.int/data/gho/data/themes/topics/indicator-groups/indicator-group-details/GHO/syphilis-incidence. Accessed April 2026.
European Centre for Disease Prevention and Control. Syphilis: Annual Epidemiological Report for 2022. Https://www.ecdc.europa.eu/en/publications-data/syphilis-annual-epidemiological-report-2022. Accessed April 2026.
National Institutes of Health. NHLBI Funding Opportunity Announcement: R01-HL-162345. Https://grants.nih.gov/grants/guide/pa-files/PA-21-256.html. Accessed April 2026.
Dr. Priya Deshmukh
Senior Editor, Health
Dr. Deshmukh is a practicing physician and renowned medical journalist, honored for her investigative reporting on public health. She is dedicated to delivering accurate, evidence-based coverage on health, wellness, and medical innovations.
