Smokers who make the decision to quit will experience immediate health benefits, including a rapid reduction in their risk of atrial fibrillation (A-Fib), according to new research published in JACC: Clinical Electrophysiology. The study, conducted by Dr. Gregory Marcus, a cardiologist at the University of California, San Francisco, offers compelling evidence for smokers to quit, showing that it’s never too late to avoid the damaging effects of smoking on heart health.

Dr. Marcus, the senior author of the study, emphasized that A-Fib can be prevented even in individuals who have smoked for years. "The findings provide a compelling new reason to show current smokers that it’s not too late to quit, and that having smoked in the past doesn’t mean you’re ‘destined’ to develop A-Fib," Marcus explained. "Even for the current and longtime smoker, A-Fib can still be avoided."

What is Atrial Fibrillation (A-Fib)?

"There’s strong evidence that smoking increases the risk of A-Fib," Marcus said. "But the benefits of quitting smoking have been less certain." With this in mind, his team sought to determine whether quitting could significantly lower a person’s risk of developing A-Fib, or if the risk would remain the same.

The research team analyzed data from over 146,700 current and former smokers, tracking their smoking habits and health over a 12-year period using data from the UK Biobank database. The results were promising: former smokers had a 13% lower risk of developing A-Fib compared to current smokers, while those who quit during the study saw an 18% reduction in their risk.

"This is likely a testament to the potency of reducing atrial fibrillation risk pretty shortly after quitting," Marcus said in a statement from the American College of Cardiology.

The findings highlight the importance of quitting smoking, not only for general health but specifically for reducing the risk of serious heart conditions like A-Fib.

Tips for Quitting Smoking

Quitting smoking is one of the most effective ways to lower the risk of A-Fib and improve overall heart health. While it can be challenging, the benefits of quitting are clear and immediate. Here are some tips to help you quit smoking successfully:

1. Choose a specific date to quit smoking and stick to it. Prepare yourself mentally and physically for this change.

2. Reach out to family, friends, or a support group to help keep you accountable. Sharing your goals with others can provide encouragement.

3. Options like nicotine patches, gum, or lozenges can help ease withdrawal symptoms and reduce cravings.

4. Identify situations that make you want to smoke, such as stress or social gatherings, and find healthy ways to cope with them.

5. Regular exercise can help distract you from cravings and improve your mood during the quitting process.

6. Drinking water can help flush nicotine out of your system faster, reducing cravings.

7. Activities like yoga, meditation, or deep breathing exercises can help manage stress, a common trigger for smoking.

Quitting smoking offers immediate and significant benefits, particularly in reducing the risk of atrial fibrillation. The latest research provides smokers with more motivation to quit, showing that it's never too late to take control of their heart health.

Every year, thousands of seemingly healthy people—often young, active, and without obvious warning signs—die suddenly due to cardiac arrest. For decades, doctors have struggled to reliably identify which patients with heart conditions are at high risk and who might be unnecessarily undergoing invasive interventions. That may be about to change.

In a breakthrough that could transform how we predict—and prevent—sudden cardiac death, scientists at Johns Hopkins University have developed an artificial intelligence model that vastly outperforms current clinical standards in identifying people most at risk. Their new system, known as MAARS (Multimodal AI for Arrhythmia Risk Stratification), not only forecasts risk with up to 93% accuracy in vulnerable age groups, but also explains why someone is high risk—something most algorithms fail to do.

The focus of the study is hypertrophic cardiomyopathy (HCM), one of the most common inherited heart conditions. It affects around 1 in 200 to 500 people globally and is a leading cause of sudden cardiac death in athletes and young adults. While most individuals with HCM live normal lives, a subset is at high risk for lethal arrhythmias—heart rhythm disturbances that can cause the heart to stop without warning. And here’s the catch: right now, doctors only have a 50-50 shot at predicting who will be affected.

“Currently we have patients dying in the prime of their life because they aren’t protected,” said Dr. Natalia Trayanova, senior author of the study and a leading figure in AI cardiology research. “And others are putting up with defibrillators for the rest of their lives with no benefit.”

Trayanova is referring to implantable cardioverter defibrillators (ICDs)—tiny devices inserted into the chest that deliver electric shocks to correct abnormal heart rhythms. They save lives in the right patients but come with physical, emotional, and financial burdens when used unnecessarily.

The need for a more precise, personalized tool has never been greater.

What the AI Model Does Differently?

Published in Nature Cardiovascular Research, the new model represents a significant departure from traditional clinical guidelines used across the US and Europe.

MAARS doesn’t rely on a single data source. Instead, it analyzes a multimodal spectrum of information—ranging from electronic health records and patient histories to contrast-enhanced cardiac MRI images that reveal scarring, or fibrosis, within the heart.

Scarring is a key factor in determining sudden death risk in HCM. But interpreting these raw images is extremely challenging for even seasoned cardiologists. That’s where AI has the edge.

“People have not used deep learning on those images,” Trayanova explained. “We are able to extract this hidden information in the images that is not usually accounted for.”

The AI essentially spots dangerous patterns in the heart’s scar tissue that the human eye—and even conventional software—can’t see.

How Accurate Is It?

In clinical tests involving real-world patients from Johns Hopkins Hospital and Sanger Heart & Vascular Institute in North Carolina, the results were staggering:

• Traditional clinical guidelines correctly predicted sudden cardiac death risk only 50% of the time.
• The MAARS model achieved an overall accuracy of 89%.
• In patients aged 40 to 60—a group particularly vulnerable to undetected risk—the model was 93% accurate.

What makes this even more valuable is its ability to provide explanations. The system doesn't just say "this patient is high risk"—it breaks down the why, giving cardiologists critical information to tailor treatment plans.

“This significantly enhances our ability to predict those at highest risk compared to our current algorithms,” said co-author Dr. Jonathan Crispin, a Johns Hopkins cardiologist. “It has the power to transform clinical care.”

Why This Could Be Transformative?

MAARS isn't the first AI model from Trayanova’s lab. In 2022, her team built another tool that provided survival predictions for patients with prior heart attacks, known as infarcts. But this latest model breaks new ground by tackling one of the most elusive forms of cardiac risk—arrhythmias caused by scarring in inherited heart conditions. The potential benefits are wide-ranging:

• Lives saved by identifying at-risk patients who might otherwise be missed.
• Better quality of life for patients who avoid unnecessary ICD implantation.
• More personalized treatment plans based on detailed, AI-generated insight.

Importantly, the model was trained and validated across diverse demographics, showing consistent performance regardless of age, gender, or ethnicity.

The researchers aren’t stopping here. They plan to expand MAARS to include other forms of arrhythmia-related heart diseases, such as cardiac sarcoidosis and arrhythmogenic right ventricular cardiomyopathy—conditions that also carry a high risk of sudden death but suffer from diagnostic ambiguity.

They’re also working to test the model in larger, more varied populations to move it closer to clinical adoption.

A New Era in Cardiology?

Artificial intelligence has long been hyped as the future of medicine. But MAARS is more than hype—it’s a working proof of concept that shows how deep learning can complement medical expertise, not replace it.

AI may soon become your cardiologist’s most powerful diagnostic tool—one that sees what even the best-trained human eyes might miss. And when lives are on the line, that kind of clarity could mean everything.

India is struggling with alarmingly high levels of premature deliveries and low birth weights in infants, and the cause could be one of the nation's most pressing environmental threats—air pollution.

As per India's National Family Health Survey-5 (2019–21), about 13% of infants were born pre-term and 17% were low birth weight, with the research identifying airborne fine particulate matter or PM2.5 as a key driver of these negative birth outcomes. The results, published in PLoS Global Public Health, are the outcome of cross-institutional collaboration between Indian and global research centers. By uniting large-scale health survey data with air quality remote sensing, the scientists have mapped not only the extent of the problem but also its underlying environmental causes.

The research, conducted in association with India's leading scientific institutions such as IIT Delhi, International Institute for Population Sciences (Mumbai), and collaborating UK and Irish partners, merged public health information with high-resolution satellite images to evaluate the impact of air pollution on pregnancies. With sophisticated spatial modeling and statistical analysis, researchers found that increased exposure to PM2.5 during pregnancy was associated with a 70% greater risk of preterm birth and a 40% greater chance of low birth weight.

This is a major public health issue, with both outcomes having long-term health consequences for infants, from cognitive disabilities to chronic conditions such as diabetes and heart disease in adult life.

What Connects Air Pollution with Preterm Births?

At the center of the crisis is fine particulate matter (PM2.5)—small airborne particles smaller than 2.5 microns in diameter, emitted primarily from the combustion of fossil fuels and biomass. The particles are tiny enough to reach deep into the lungs and into the bloodstream, and they threaten the health of mothers and fetuses equally.

The research determined that higher exposure to PM2.5 during pregnancy was linked with a 40% increased likelihood of low birth weight and a 70% increased risk of preterm delivery. The rise of 10 microgram per cubic meter (μg/m³) in PM2.5 exposure was correlated with a 5% increase in the prevalence of low birth weight and a 12% increase in preterm delivery.

These results are consistent with global evidence, including a recent meta-analysis, which reported a similar dose-response pattern between exposure to PM2.5 and adverse birth outcomes globally. Exposure to other PM2.5 components—black carbon, nitrates, and sulfates—has also been associated with spontaneous preterm birth, especially in the second trimester.

The research identified glaring regional inequities. States in the higher Gangetic plains of North India, including Punjab, Delhi, Uttar Pradesh, Haryana, and Bihar, demonstrated the greatest PM2.5 levels. These states also had the greatest rates of premature births and low birth-weight babies. For example, Himachal Pradesh reported a whopping 39% premature birth rate, followed by Uttarakhand (27%), Rajasthan (18%), and Delhi (17%).

Conversely, the northeastern states of Mizoram, Manipur, and Tripura did notably better, with reduced air pollution rates and associated improved outcomes at birth. The results indicate the imperative for focused policy action in northern India, where urbanization, agricultural burning, and the use of fossil fuels are pushing perilously bad air quality.

Can Climate Change Is Add to the Crisis?

Aside from air pollution, other climate factors like temperature and changes in rainfall patterns also affected pregnancy outcomes, according to the Indian study. The study observes that intense heat waves, irregular monsoons, and water shortages—characteristics of the climate emergency—can directly affect the health of the mother and fetus.

With this convergence of environmental and reproductive health, specialists are increasingly advocating for the incorporation of climate adaptation measures in public health planning. Localized heat action plans, improved water management systems, and effective risk communication systems are among these.

How Air Pollution Harms Pregnancies?

The journey from contaminated air to poor birth outcomes is both subtle and direct. PM2.5 and its components have the ability to penetrate the placental barrier, leading to inflammation and oxidative stress in the placental tissue. This inflammation is directly related to preterm labor, low birth weight, and even neurodevelopmental delay in children.

Black carbon, one of the dominant fractions of PM2.5, has been found to interfere with fetal development and raise the risk of preeclampsia and preterm rupture of membranes, further putting mother and child at risk. The additive effect is increased odds of babies being born too early or too light, with health consequences for life.

India's National Clean Air Programme (NCAP), initiated in 2019, plans to lower PM levels by 20–30% in 122 non-attainment cities by 2024. It's good that it is a move towards improvement, but according to researchers, efforts need to be scaled up and enforced more strictly, particularly in the northern belt where pollution levels are still critically high.

The researchers of the study also suggest greater public health outreach, including education campaigns for pregnant women, frontline health workers, and policymakers. Education about air quality monitoring, prenatal care access, and simple measures to avoid exposure are crucially necessary.

How Pregnant Women Can Protect Themselves?

Although systemic change is necessary, there are also measures individuals—particularly pregnant women—can take to lower their risk:

• Monitor local air quality and limit outdoor activities when pollution levels are high.
• Use air purifiers and maintain clean indoor environments.
• Avoid heavily trafficked roads and industrial areas whenever possible.
• Eat a diet rich in antioxidants, which may help counteract some of the harmful effects of air pollutants.

Yet, with air pollution still on the increase, such individual precautions need to be supplemented by strong public health and policy measures so that meaningful protection for both mothers and infants is guaranteed.

This research reinforces a growing body of international evidence that links air pollution to reproductive and neonatal health risks. According to the World Health Organization, over 90% of the global population breathes unsafe outdoor air, and half are exposed to indoor pollution from traditional cooking methods involving coal, dung, or wood.

Worldwide, 15 million babies are born prematurely each year, and so preterm birth is the predominant cause of neonatal deaths. By which standards is the Indian study a local health concern—it's a global warning for health.

Five years after the peak of the global pandemic, the world continues to grapple with the evolving landscape of Covid-19. The latest twist comes from the United Kingdom, where a new strain dubbed ‘Stratus’ has rapidly become the most prevalent variant, accounting for nearly a third of all cases in England. What sets Stratus apart is not just its speed of spread, but a unique and unexpected symptom, a hoarse voice.

With experts warning of increased immune evasion and the World Health Organization (WHO) keeping the strain under close surveillance, the emergence of Stratus and its sub-variants XFG and XFG.3 is a timely reminder that the fight against Covid-19 is far from over.

What Is New Covid Variant Stratus?

First identified in January 2025, the Stratus strain—officially classified under the XFG lineage and its subvariant XFG.3—has become the most common form of COVID-19 in England. According to the UK Health Security Agency (UKHSA), the XFG.3 variant currently accounts for a greater proportion of cases than any other single strain, with Stratus overall making up roughly 30% of infections in the region.

The World Health Organization (WHO) has designated Stratus as a "variant under monitoring," a classification that signals the need for heightened genomic tracking, though it has emphasized the variant currently poses a low risk to global public health.

What sets Stratus apart from prior variants, particularly its Omicron predecessors, is a peculiar but increasingly common symptom: a hoarse or raspy voice, an anomaly not prominently associated with COVID-19 strains before.

Dr. Alex Allen, Consultant Epidemiologist at UKHSA, emphasizes that while viruses naturally mutate over time, the Stratus strain’s unique symptom profile and rapid spread warrant careful monitoring.

Stratus is not just another offshoot of Omicron; it is what scientists call a “recombinant” or “Frankenstein” variant. This means it emerged when an individual was infected with two different Covid strains simultaneously, resulting in a new hybrid lineage. Such recombination events are rare but can lead to variants with novel characteristics—including changes in transmissibility, immune evasion, and symptomatology.

Reports from the World Health Organization indicate that Stratus is showing signs of additional immune evasion compared to other strains. This means it may more effectively bypass existing immunity from previous infections or vaccinations, contributing to its rapid spread.

How Widespread Is Stratus Globally?

As of June 22, 2025, Stratus has been detected in 38 countries, according to the World Health Organization. In addition to its prevalence in the UK, it is showing a slow but steady increase in several regions across Southeast Asia and Europe, and health authorities in the United States are closely monitoring imported cases.

The WHO noted that several nations have reported rising case counts and mild upticks in hospitalization rates alongside increased detection of XFG. However, current evidence does not indicate that Stratus causes more severe illness or higher mortality than other circulating Omicron variants.

As of late June 2025, Stratus accounted for 22.7 percent of global Covid-19 cases, according to the WHO. It has been detected in 38 countries, reflecting its global reach. The UK remains the epicenter, but rising case numbers have also been reported in South-East Asia, Australia, and several U.S. states.

The true scale of the spread, however, is difficult to measure. With widespread reductions in Covid-19 testing compared to the height of the pandemic, many cases may go undetected or unreported. This underlines the importance of genomic surveillance and international cooperation in tracking emerging variants.

Recognizing the Symptoms of Stratus Strain

While the hoarse voice is the most distinctive symptom reported with Stratus, health authorities have not yet listed any other unique symptoms for this variant. The classic symptoms of Covid-19—including fever, persistent cough, loss of taste or smell, fatigue, headache, and sore throat—remain common.

The NHS continues to advise the public to watch for:

• High temperature or shivering
• New, continuous cough
• Shortness of breath
• Loss or change in sense of smell or taste
• Feeling tired or exhausted
• Aching body
• Headache
• Sore throat
• Blocked or runny nose
• Loss of appetite
• Diarrhea
• Nausea or vomiting

The emergence of a hoarse voice as a prominent symptom highlights the need for ongoing vigilance and public awareness, especially as new variants may present in unexpected ways.

Is Stratus Variant More Dangerous?

So far, there is no evidence that Stratus causes more severe disease than previous variants. Dr. Alex Allen, Consultant Epidemiologist at UKHSA, stated that the agency continues to monitor the situation closely, adding, “It is normal for viruses to mutate and change over time.”

Dr. Allen also emphasized that COVID-19 vaccines in use remain effective against Stratus and its subvariants. While Stratus shows signs of “immune evasion,” experts clarify this doesn’t mean existing immunity—whether from vaccination or prior infection—is rendered useless. Instead, it may suggest slightly reduced protection against infection, not against severe illness.

The UK and many other countries continue to offer seasonal COVID-19 booster doses, especially for vulnerable groups. In the UK, the NHS is currently offering the vaccine to:

• Individuals aged 75 and above
• People aged 6 months to 74 with weakened immune systems
• Residents in adult care homes

The rationale remains the same: over time, vaccine-induced immunity wanes, and booster doses "top up" protection, reducing the risk of severe symptoms, hospitalization, and death.

As of now, there is no need for a new vaccine targeting Stratus, but virologists remain vigilant. The adaptability of mRNA vaccine platforms allows manufacturers to update formulations quickly, should a variant emerge that significantly escapes immunity.

While the Stratus strain doesn’t appear to be more deadly or vaccine-resistant, it’s a clear reminder that COVID-19 is not behind us. The virus continues to mutate, and new symptoms—like a hoarse voice—may require clinicians and patients to adjust their awareness of what infection might look like.

Public health experts advise individuals to stay up to date with vaccines, test if symptomatic (especially if vulnerable or in contact with high-risk individuals), and continue practicing good hygiene, particularly in crowded indoor spaces.