Unveiling the new enemies of the heart. A comprehensive review sheds light on emerging cardiovascular risk factors

An extensive review published in the European Heart Journal, coordinated by researchers from Fondazione Policlinico Gemelli in collaboration with distinguished American experts such as Deepak Bhatt from Mount Sinai in New York and Sanjay Rajagopalan from Case Western Reserve University in Cleveland, focuses on the cardiovascular risks of the third millennium. The dominating factors include air pollution, pivotal to climate change. Additionally, the review highlights the impact of light and noise pollution, mental health, social isolation, and infectious diseases (such as flu and Covid-19). Understanding these new enemies of the heart is crucial in order to prompt immediate individual initiatives and adequate policy actions.

The enemies of the heart and coronary arteries extend far beyond traditional factors, commonly referred to as modifiable risk factors or SMuRFs (cholesterol, diabetes, hypertension, smoking). While the classic risk factors should not be dismissed, it is noteworthy that at least 15% of heart attack victims exhibit no known risk factors. Therefore, a broader perspective is necessary to illuminate the new dangers that demand attention. A review article published on the European Heart Journal, led by Dr. Rocco A. Montone, synthesizes these novel risks under the umbrella term "exposome." The exposome encompasses factors such as environmental pollution, socio-economic and psychological factors (stress, depression, social isolation), and infectious diseases like influenza and Covid-19.

"While treatments for traditional risk factors have become increasingly effective over the years –stresses Dr. Rocco Montone, cardiologist at the UOC Intensive Cardiology at Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome - Università Cattolica -  ischemic heart disease remains the leading cause of death worldwide. Therefore, attention is shifting from traditional risk factors to the broader environment we inhabit, filled with pollution, viruses, economic and psychological issues that substantially contribute to the problem of ischemic heart disease."

Environmental Pollution: Air pollution, especially from PM2.5 (fine particulate), can independently reduce life expectancy by 2.9 years (tobacco smoke reduces it by 2.2 years). In 2019, the Global Burden of Disease study attributed seven million deaths worldwide to pollution, with cardiovascular diseases being a primary cause. “Air pollution oxidizes LDL cholesterol, making it more dangerous, and alters the functionality of HDL cholesterol, thereby reducing the efficacy of statins – highlights Dr. Montone -. Acute exposure to PM2.5 from diesel vehicle emissions can lead to a sudden increase in blood pressure. Air pollutants can also affect insulin sensitivity, promoting the onset of diabetes”.

Noise and light pollution, along with social stress, can exacerbate oxidative stress, inflammatory responses, and contribute to endothelial dysfunction, platelet aggregation, and the emergence of ischemic heart disease. Soil pollution, (heavy metals and pesticides), can contaminate food and water, further contributing to adverse cardiac events. Climate change, closely linked to pollution, also significantly impacts heart health, with prolonged exposure to heat correlating to increased cardiovascular mortality.

Mental Health: Chronic stress, depression, social isolation, and loneliness contribute significantly to cardiovascular diseases. Stress triggers sympathetic nervous system hyperactivity, leading to hypertension, while increased cortisol production promotes insulin resistance and visceral obesity. Stress is often associated with unhealthy lifestyle habits, compounding traditional cardiovascular risk factors.

Infectious Diseases: Respiratory infections such as flu and COVID-19, as well as periodontitis (gum diseases) and infections like Helicobacter pylori and Chlamydia, are linked to an increased cardiovascular risk. “These infections – affirms dr. Montone - promote systemic inflammation, oxidative stress, platelet activation, and can also directly damage heart cells”.

Mitigation Strategies (Embracing Awareness): “Addressing the exposome to protect the heart is not as straightforward as taking a pill against cholesterol or blood pressure – aknowledges dr. Montone -. While individual responsibility is crucial, higher-level environmental policies and mitigation actions are necessary and mandatory. Nevertheless, being aware of these risks is vital, and every individual should make evety effort to reduce these risk factors concerning both individuals and the society as a whole.

“Possible measures to combat environmental pollution – suggests dr. Montone – range from the transition from fossil fuels to renewable energy, implementing traffic reduction policies in urban centers, and promoting low-emission or zero-emission transportation. Urban

 planning should consider separating industrial and residential areas, and outdoor exercise is recommended in green spaces away from traffic. In times of high pollution, wearing a mask or staying indoors with closed windows and air purifiers may be advisable. Strategies for reducing noise pollution include adopting technologies to reduce transportation noise, regulating traffic, encouraging electric vehicle use, designing noise-resistant buildings, and creating green areas as natural noise buffers. Combatting light pollution involves public and personal efforts, such as turning off lights for better sleep hygiene and using eye masks. Even dietary choices play a role, and adopting a sustainable diet like the Mediterranean diet, which includes reducing red meat consumption, benefits personal health and the environment”.

“As for the infectious diseases jeopardizing the heart - continues Dr. Montone – of fundamental importance are the autumn vaccination campaigns against influenza and COVID-19, but also promoting hand hygiene, surface and environmental sanitization, and wearing face masks in crowded indoor spaces.

“Of equal importance – remarks Professor Filippo Crea, Editor-in-Chief of European Heart Journal and Director of the Center of Excellence for Cardiovascular Sciences at Gemelli Hospital Island (Rome) - Università Cattolica -  is to increase the social awareness of the problem and to incorporate these new cardiovascular risk factors in major cardiovascular guidelines. At the same time, there is still much work to be done in implementing preventive and mitigation strategies. In this context, healthcare professionals and public organizations should be aware of the need to address and endorse this paradigm shift. Moreover, further research is crucial to explore how these emerging risk factors, individually and in combination, impact the integrity of the cardiovascular system. A recent epidemiological study published in the New England Journal of Medicine* demonstrates that known risk factors (hypertension, diabetes, hypercholesterolemia, and smoking) account for only half of cardiovascular diseases”.

** N Engl J Med 2023; 389:1273-1285 DOI: 10.1056/NEJMoa2206916