In women, a low resting heart rate is associated with a slightly raised incidence of criminal offending as well as of unintentional injuries, in a large all-female study published March 27 in the open-access journal PLOS ONE by Sofi Oskarsson of School of Behavioural, Social and Legal Sciences, Örebro University, Sweden, and colleagues. This is the first time such an association has been shown in women, although it is well established in studies of men.
Intervention efforts for crime tend to focus on structural and social factors as well as personality traits and behaviors. Less is known about biological factors, although there is an established association between the autonomic nervous system – a network of nerves that regulates unconscious body processes like breathing and heartbeat – and criminal offending in men. Sofi Oskarsson and colleagues from Örebro University, Sweden, wanted to see if the same is observed in women.
Using population registers, the team identified 12 500 Swedish women who volunteered for military service at around 18 years old, where physical assessments recorded resting heart rate and blood pressure. They also tracked records for violent and nonviolent criminal offences and unintentional injuries for up to 40 years.
Female conscripts with the lowest resting heart rates (under 69bpm) had 35% higher risk for any criminal conviction compared to those with rates above 83bpm. However, no significant associations were found for violent crime. Lower resting heart rate was associated with an increased risk of unintentional injuries, which in past research has been interpreted as potentially reflecting fearlessness and stimulation seeking tendencies. The team found a significant association between blood pressure and violent crime, but no significant association was found for non-violent crime.
The authors state that low autonomic nervous system arousal might drive stimulation-seeking tendencies, but that their findings should be interpreted with caution. They saw lower rates of criminal offending compared to women who had not done military service, and a higher rate of unintentional injuries, so further work is needed to establish whether the same is seen in wider cohorts. If replicated by further research, this finding could have the potential to serve as a predictor of criminal offending, in women as well as men.
The authors add: “Our research reveals a compelling link between lower resting heart rate and an elevated risk of criminality and unintentional injuries among female conscripts. This association, previously underscored primarily in men, paves way for innovative strategies predicting crime risk among women.”
Experiencing puberty earlier, compared to same-age peers, may be one of the mechanisms through which childhood risk factors influence adult cardiometabolic health issues, according to a study published March 27, 2024 in the open-access journal PLOS ONE by Maria Bleil from the University of Washington, USA and colleagues.
Adverse experiences in childhood are frequently linked to poor health in adulthood. Most of the conceptual models describing adversity-related changes that may be adaptive to stress in the short-term but are risky to long-term health don’t specifically include puberty, which links childhood and adulthood and is itself also sensitive to the child’s environment. Earlier onset of puberty is often linked to factors like race (with Black and Latina girls developing earlier than White girls), mother’s age at her first period, infant weight gain and childhood obesity, and adverse experiences like childhood socioeconomic disadvantage, stressful parent-child relationships, and other stressful life events.
Here, Bleil and colleagues modeled pubertal timing and health risks in a cohort of women who had participated in the 30-year NICHD Study of Early Child Care and Youth Development prospective study of children and their families. Participants were followed from birth to adolescence (1991–2009) to examine trajectories of child health and development, with an additional in-person study follow-up (2018–2022) among participants ages 26 to 31 to capture social, behavioural, and health status information in adulthood. The authors fit models to data from the full sample of 655 women.
The authors found that later pubertal onset (later breast development, pubic hair onset, and first period) predicted lower adulthood cardiometabolic risk. These puberty indicators were also found to mediate the effects of factors like mother’s age at her first period, race, BMI percentile, and childhood socioeconomic status on adult cardiometabolic risk.
It’s important to note that this study maps predictive relationships between childhood risk factors, timing of puberty, and adulthood cardiometabolic risks, but cannot prove causation. That said, the pattern of results provides strong longitudinal evidence for the role of puberty onset as a pathway linking early life exposures and adulthood cardiometabolic health – and suggests targeting puberty onset may improve health more broadly in at-risk girls. The authors hope future studies will both replicate their findings and better characterise the nature of the links identified here.
The authors add: “This study suggests the timing of pubertal development in girls is an important pathway through which early life risk factors, such as prepubertal body mass index and socioeconomic position, influence cardiometabolic health in adulthood. The implications of this work are that pubertal development and its timing should be considered, and potentially targeted, in efforts to improve cardiometabolic health.”
Managing circadian rhythms through intense light and chronologically timed therapy can help prevent or treat a variety of circulatory system conditions including heart disease, according to a new study published in Circulation Research.
“The impact of circadian rhythms on cardiovascular function and disease development is well established,” said the study’s lead author Tobias Eckle, MD, PhD, professor of anaesthesiology at the University of Colorado School of Medicine.
“However, translational preclinical studies targeting the heart’s circadian biology are just now emerging and are leading to the development of a novel field of medicine termed circadian medicine.”
The senior author is Professor Tami A. Martino, PhD, distinguished chair in molecular and cardiovascular research at the University of Guelph in Ontario, Canada.
The study reviews current circadian medicine research, focusing on the use of intense light therapy following surgery, utilizsng light to treat cardiac injury, exploring how cardiovascular disease can differ between men and women and administering drugs at specific times of day to coincide with the body’s internal clock to speed healing.
It also urges more aggressive use of this therapy in humans, rather than relying on mostly animal models.
“There are literally millions of patients who could benefit from this,” Eckle said.
“The treatments are almost all low-risk. Some involve using light boxes and others use drugs that are already on the market.”
Circadian rhythms significantly influence how the cardiovascular system operates. Timing is everything. Blood pressure and heart rates follow distinct patterns, peaking during the day and ebbing at night. When this is disrupted, it leads to worse cardiovascular disease outcomes including myocardial infarction and heart failure. Light is critical in maintaining the proper balance and functioning of the body. Shift employees who may work night hours then day hours often have worse cardiac outcomes.
Eckle, who has studied circadian rhythm and health for years, said intense light can help heal the body after heart surgery while protecting it from injury during surgery, including reducing the chances of cardiac ischemia.
According to the researchers, when light hits the human eye it is transmitted to the suprachiasmatic nucleus, a structure in the brain’s hypothalamus that regulates most circadian rhythms in the body.
Intense light stabilizes the PER2 gene and increases levels of adenosine, which blocks electrical signals in the heart that cause irregular rhythms, making it cardiac protective.
Eckle has used light therapy with patients after surgery and seen positive results including lower levels of troponin, a key protein whose elevation can signal a heart attack or stroke.
Given the mounting evidence that intense light and timed drug treatments are effective, he said, it is time to move forward with more clinical trials.
“Circadian rhythms play a crucial role in cardiovascular health, influencing the timing of onset and severity of cardiovascular events and contributing to the healing process from disease,” Eckle said. “Studies in humans are clearly required. Regarding intense light therapy, chronotherapy and restricted feeding are low-risk strategies that should be tested sooner than later.”
Replacing table salt with a salt substitute can reduce incidence of hypertension in older adults without increasing their risk of hypotension episodes, according to a recent study in the Journal of the American College of Cardiology. Participants using a salt substitute had a 40% lower incidence and likelihood of experiencing hypertension compared to those who used regular salt.
One of the most effective ways to reduce hypertension risk, one of the world’s leading health risks, is to reduce sodium intake. This study looks at salt substitutes as a better solution to control and maintain healthy blood pressure than reducing salt alone.
“Adults frequently fall into the trap of consuming excess salt through easily accessible and budget-friendly processed foods,” said Yangfeng Wu, MD, PhD, lead author of the study and Executive Director of Peking University Clinical Research Institute in Beijing, China.
“It’s crucial to recognise the impact of our dietary choices on heart health and increase the public’s awareness of lower-sodium options.”
Researchers in this study evaluated the impact of sodium reduction strategies on blood pressure in elderly adults residing in care facilities in China.
While previous studies prove that reducing salt intake can prevent or delay new-onset hypertension, long-term salt reduction and avoidance can be challenging.
The DECIDE-Salt study included 611 participants 55 years or older from 48 care facilities split into two groups: 24 facilities (313 participants) replacing usual salt with the salt substitute and 24 facilities (298 participants) continuing the use of usual salt.
All participants had blood pressure <140/90mmHg and were not using anti-hypertension medications at baseline.
The primary outcome was participants who had incident hypertension, initiated anti-hypertension medications or developed major cardiovascular adverse events during follow-up.
At two years, the incidence of hypertension was 11.7 per 100 people-years in participants with salt substitute and 24.3 per 100 people-years in participants with regular salt.
People using the salt substitute were 40% less likely to develop hypertension compared to those using regular salt. Furthermore, the salt substitutes did not cause hypotension, which can be a common issue in older adults.
“Our results showcase an exciting breakthrough in maintaining blood pressure that offers a way for people to safeguard their health and minimise the potential for cardiovascular risks, all while being able to enjoy the perks of adding delicious flavour to their favourite meals,” Wu said.
“Considering its blood pressure – lowering effect, proven in previous studies, the salt substitute shows beneficial to all people, either hypertensive or normotensive, thus a desirable population strategy for prevention and control of hypertension and cardiovascular disease.”
Limitations of the study include that it is a post-hoc analysis, study outcomes were not pre-specified and there was a loss of follow-up visits in many patients.
Analyses indicated that these missing values were at random, and multiple sensitivity analyses supports the robustness of the results.
In an accompanying editorial comment, Rik Olde Engberink, MD, PhD, researcher, nephrologist and clinical pharmacologist at Amsterdam University Medical Center’s Department of Internal Medicine, said the study provides an attractive alternative to the failing strategy to reduce the intake of salt worldwide, but questions and effort remain.
“In the DECIDE-Salt trial, the salt substitute was given to the kitchen staff, and the facilities were not allowed to provide externally sourced food more than once per week,” Olde Engberink said. “This approach potentially has a greater impact on blood pressure outcomes, and for this reason, salt substitutes should be adopted early in the food chain by the food industry so that the sodium-potassium ratio of processed foods will improve.”
In a potentially game-changing development, scientists at Virginia Tech have revealed a new understanding of sometimes fatal viral infections that affect the heart.
The focus has mostly been on myocarditis, which is often triggered by the body’s immune response to a viral infection. Now, a new study led by James Smyth, associate professor at the Fralin Biomedical Research Institute, sheds new light on this notion, revealing that the virus itself creates potentially dangerous conditions in the heart before inflammation sets in.
The discovery, now online and set to appear in the March 29 issue of Circulation Research, suggests completely new directions to diagnose and treat viral infections affecting the heart.
Given the high incidence of viral-related myocarditis leading to sudden cardiac death, the insight is crucial. Up to 42% of sudden cardiac deaths in young adults are attributed to myocarditis, and of these cases viral infection is the leading cause.
“From a clinical perspective, our understanding of viral infection of the heart has focused on inflammation, causing problems with the rate or rhythm of the heartbeat,” Smyth said. “But we have found an acute stage when the virus first infects the heart and before the body’s immune response causes inflammation. So even before the tissue is inflamed, the heart is being set up for arrhythmia.”
To make this discovery, researchers focused on adenovirus, a common culprit in cardiac infection and myocarditis, using Mouse Adenovirus Type-3 to replicate the human infection process.
They found that early in the infection, the virus disrupts critical components of the heart’s communication and electrical systems.
As a result, even before symptoms appear, the adenoviral infection creates conditions that disrupt the heart’s gap junctions and ion channels, according to virologist Rachel Padget, the study’s first author who worked in the Smyth lab while completing a doctoral degree from the Virginia Tech Translational Biology, Medicine, and Health graduate program.
Gap junctions are like tiny tunnels between heart cells that allow them to communicate, and ion channels are like gates in the cell membranes that help maintain the right balance of ions needed for the heart to generate normal patterns of electrical activity that allow it to beat properly.
When adenoviral infection disturbs these communication bridges and gatekeepers, it creates a situation where the heart might develop irregular patterns of electrical activity called arrhythmias affecting its mechanical beating and blood pumping capacity, and that can lead to sudden cardiac problems, especially in people with active infections.
Now, by targeting specific heart changes induced by viral infections at the molecular level, researchers aim to reduce the risk of cardiac issues in people grappling with viral illnesses.
“Individuals who have acute infections can look normal by MRI and echocardiography, but when we delved into the molecular level, we saw that something very dangerous could occur,” Smyth said. “In terms of diagnostics, we can now work with our colleagues here to start looking ways to analyse blood for a biomarker of the more serious problem. People get cardiac infections all the time and they recover. But can we identify what’s different about individuals that are at a higher risk to have the arrhythmia, possibly through a simple blood test in the doctor’s office.”
Researchers have developed a new catheter-based device that combines two powerful optical techniques to image atherosclerotic plaques that can build up inside the heart’s coronary arteries. By providing new details about plaque, the device could help clinicians and researchers improve treatments for preventing heart attacks and strokes.
“Atherosclerosis, leading to heart attacks and strokes, is the number one cause of death in Western societies – exceeding all combined cancer types – and, therefore, a major public health issue,” said research team member leader Laura Marcu from University of California, Davis. “Better clinical management made possible by advanced intravascular imaging tools will benefit patients by providing more accurate information to help cardiologists tailor treatment or by supporting the development of new therapies.”
In the Optica Publishing Group journal Biomedical Optics Express, researchers describe their new flexible device, which combines fluorescence lifetime imaging (FLIM) and polarisation-sensitive optical coherence tomography (PSOCT) to capture rich information about the composition, morphology and microstructure of atherosclerotic plaques. The work was a collaborative project with Brett Bouma and Martin Villiger, experts in OCT from the Wellman Center for Photomedicine at Massachusetts General Hospital.
“With further testing and development, our device could be used for longitudinal studies where intravascular imaging is obtained from the same patients at different timepoints, providing a picture of plaque evolution or response to therapeutic interventions,” said Julien Bec, first author of the paper. “This will be very valuable to better understand disease evolution, evaluate the efficacy of new drugs and treatments and guide stenting procedures used to restore normal blood flow.”
Gaining an unprecedented view
Most of what scientists know about how atherosclerosis forms and develops over time comes from histopathology studies of postmortem coronary specimens. Although the development of imaging systems such as intravascular ultrasound and intravascular OCT has made it possible to study plaques in living patients, there is still a need for improved methods and tools to investigate and characterise atherosclerosis.
To address this need, the researchers embarked on a multi-year research project to develop and validate multispectral FLIM as an intravascular imaging modality. FLIM can provide insights into features such as the composition of the extracellular matrix, the presence of inflammation and the degree of calcification inside an artery. In earlier work, they combined FLIM with intravascular ultrasound, and in this new work they combined it with PSOCT. PSOCT provides high-resolution morphological information along with birefringence and depolarisation measurements. When used together, FLIM and PSOCT provide an unprecedented amount of information on plaque morphology, microstructure and biochemical composition.
“Birefringence provides information about the plaque collagen, a key structural protein that helps with lesion stabilization, and depolarisation is related to lipid content that contributes to plaque destabilization,” said Bec. “Holistically, this hybrid approach can provide the most detailed picture of plaque characteristics of all intravascular imaging modalities reported to date.”
Getting two imaging modalities into one device
The development of multimodal intravascular imaging systems compatible with coronary catheterisation is technologically challenging. It requires flexible catheters < 1mm diameter that can operate in vessels with sharp twists and turns. A high imaging speed of around 100 frames/second is also necessary to limit cardiac motion artefacts and ensure proper imaging inside an artery.
To integrate FLIM and PSOCT into a single device without compromising the performance of either imaging modality, the researchers used optical components previously developed by Marcu’s lab and other research groups. Key to achieving high PSOCT performance was a newly designed rotary collimator with high light throughput and a high return loss, ie the ratio of power reflected back toward the light source compared to the power incident on the device. The catheter system they developed has similar dimensions and flexibility as the intravascular imaging devices that are currently in clinical use.
After testing the new system with artificial tissue to demonstrate basic functionality on well characterized samples, the researchers also showed that it could be used to measure properties of a healthy coronary artery removed from a pig. Finally, in vivo testing in swine hearts demonstrated that the hybrid catheter system’s performance was sufficient to support work toward clinical validation. These tests all showed that the FLIM-PSOCT catheter system could simultaneously acquire co-registered FLIM data over four distinct spectral bands and PSOCT backscattered intensity, birefringence and depolarization information.
Next, the researchers plan to use the intravascular imaging system to image plaques in ex vivo human coronary arteries. By comparing the optical signals acquired using the system with plaque characteristics identified by expert pathologists, they can better understand which features can be identified by FLIM-PSOCT and use this to develop prediction models. They also plan to move forward with testing in support of clinical validation of the system in patients.
An analysis of UK Biokank data showed that adults who reported drinking two litres or more of sugar- or artificially sweetened drinks per week had a higher risk of atrial fibrillation compared with adults who drank fewer such beverages, according to new research published in Circulation: Arrhythmia and Electrophysiology, a peer-reviewed journal of the American Heart Association.
The study also found that drinking one litre or less per week of pure, unsweetened juice, such as orange or vegetable juice, was associated with a lower risk of atrial fibrillation (AFib). However, the study could not confirm whether the sweetened drinks caused AFib, yet the association remained after accounting for a person’s genetic susceptibility to the condition.
Consuming sweetened drinks has been linked to Type 2 diabetes and obesity in previous research. This large study of health data in the UK Biobank is among the first to assess a possible link between sugar- or artificially sweetened beverages and AFib.
“Our study’s findings cannot definitively conclude that one beverage poses more health risk than another due to the complexity of our diets and because some people may drink more than one type of beverage,” said lead study author Ningjian Wang, MD, PhD, a researcher at the Shanghai Ninth People’s Hospital and Shanghai Jiao Tong University School of Medicine in Shanghai, China. “However, based on these findings, we recommend that people reduce or even avoid artificially sweetened and sugar-sweetened beverages whenever possible. Do not take it for granted that drinking low-sugar and low-calorie artificially sweetened beverages is healthy, it may pose potential health risks.”
The researchers reviewed data from dietary questionnaires and genetic data for more than 200 000 adults free of AFib at the time they enrolled in the UK Biobank, between 2006 and 2010. During the nearly 10-year follow-up period, there were 9362 cases of AFib among the study participants.
The analysis found:Compared to people who did not consume any sweetened drinks, there was a 20% increased risk of atrial fibrillation among people who said they drank more than 2 litres per week of artificially sweetened beverages; and a 10% increased risk among participants who reported drinking 2 litres per week or more of sugar-sweetened beverages.
People reporting 1 litre or less of pure fruit juice each week had an 8% lower risk of atrial fibrillation.
Participants who consumed more artificially sweetened beverages were more likely to be female, younger, have a higher body mass index and a higher prevalence of Type 2 diabetes.
Participants who consumed more sugar-sweetened beverages were more likely to be male, younger, have a higher body mass index, a higher prevalence of heart disease and lower socioeconomic status.
Those who drank sugar-sweetened beverages and pure juice were more likely to have a higher intake of total sugar than those who drank artificially sweetened drinks.
Smoking may have also affected risk, with smokers who drank more than two litres per week of sugar-sweetened beverages having a 31% higher risk of AFib, whereas no significant increase risk was noted for former smokers or people who never smoked.
“These novel findings on the relationships among atrial fibrillation risk and sugar- and artificially sweetened beverages and pure juice may prompt the development of new prevention strategies by considering decreasing sweetened drinks to help improve heart health,” Wang said.
Researchers also evaluated whether a genetic susceptibility to AFib was a factor in the association with sweetened beverages. The analysis found the AFib risk was high with the consumption of more than 2 litres of artificially sweetened drinks per week regardless of genetic susceptibility.
Heart disease researchers have identified a group of patients in whom international guidelines on aspirin use for heart health may not apply. In a study published in the medical journal Circulation, the findings of a review of data from three clinical trials challenge current best practice for use of the drug for primary prevention of heart disease or stroke – otherwise known as atherosclerotic cardiovascular disease.
The research examined the results from clinical trials involving more than 47 000 patients in 10 countries, including the US, the UK and Australia, which were published in 2018.
The analysis focused on findings for a subgroup of 7222 patients who were already taking aspirin before the three trials commenced. Those studied were at increased risk for cardiovascular disease and were taking aspirin to prevent the first occurrence of a heart attack or stroke.
The data showed a higher risk of heart disease or stroke – 12.5% versus 10.4% – for patients who were on aspirin before the trials and who then stopped, compared to those who stayed on the drug.
Analyses also found no significant statistical difference in the risk for major bleeding between the two groups of patients.
The research was led by Professor J. William McEvoy, Established Professor of Preventive Cardiology at University of Galway and Consultant Cardiologist at Saolta University Health Care Group, in collaboration with researchers in University of Tasmania and Monash University, Melbourne.
Professor McEvoy said: “We challenged the notion that aspirin discontinuation is a one-size-fits-all approach.”
The research team noted results from observational studies which suggest a 28% higher risk of heart disease or stroke among adults who were prescribed aspirin to reduce the risk for a first heart attack or stroke, but who subsequently chose to stop taking the aspirin without being told to do so by their doctor.
Based in large part on three major clinical trials published in 2018, international guidelines no longer recommend the routine use of aspirin to prevent the first occurrence of heart attack or stroke.
Importantly, aspirin remains recommended for high-risk adults who have already had a heart disease or stroke event, to reduce the risk of a second event.
The move away from primary prevention aspirin in recent guidelines is motivated by the increased risk of major bleeding seen with this common medication in the three trials, albeit major bleeding is relatively uncommon on aspirin and was most obvious only among trial participants who were started on aspirin during the trial, rather than those who were previously taking aspirin safely.
These trials primarily tested the effect of starting aspirin among adults who have not previously been treated with the drug to reduce the risk of atherosclerotic cardiovascular disease. Less is known about what to do in the common scenario of adults who are already safely taking aspirin for primary prevention.
Professor McEvoy said: “Our findings of the benefit of aspirin in reducing heart disease or stroke without an excess risk of bleeding in some patients could be due to the fact that adults already taking aspirin without a prior bleeding problem are inherently lower risk for a future bleeding problem from the medication. Therefore, they seem to get more of the benefits of aspirin with less of the risks.
“These results are hypothesis-generating, but at present are the best available data. Until further evidence becomes available, it seems reasonable that persons already safely treated with low-dose aspirin for primary prevention may continue to do so, unless new risk factors for aspirin-related bleeding develop.”
An analysis of 430 000 adults in the U.S. found that using cannabis, most commonly through smoking, eating or vaporising it, was significantly associated with a higher risk of heart attack and stroke, even after controlling for tobacco use (combustible cigarettes and other tobacco products) and other cardiovascular risk factors, according to new research published today in theJournal of the American Heart Association.
Although cannabis, or marijuana, is illegal at the federal level, 24 states and Washington, D.C., have legalized the use of recreational cannabis. Additionally, the number of people in the U.S. who use cannabis has increased significantly in recent decades, according to the 2019 National Survey on Drug Use and Health from the Substance Abuse and Mental Health Services Administration of the U.S. Department of Health and Human Services.
The annual survey found that in 2019, 48.2 million people ages 12 or older reported using cannabis at least once, compared to 25.8 million people ages 12 or older in 2002, an increase to 17% from 11%.
“Despite common use, little is known about the risks of cannabis use and, in particular, the cardiovascular disease risks,” said lead study author Abra Jeffers, PhD, a data analyst at Massachusetts General Hospital in Boston. “The perceptions of the harmfulness of smoking cannabis are decreasing, and people have not considered cannabis use dangerous to their health. However, previous research suggested that cannabis could be associated with cardiovascular disease. In addition, smoking cannabis – the predominant method of use – may pose additional risks because particulate matter is inhaled.”
In this study, researchers reviewed survey data collected for 430 000 adults from 2016 through 2020 to examine the association between cannabis use and adverse cardiovascular outcomes including heart disease, heart attack and stroke. The survey data was collected through the Behavioral Risk Factor Surveillance System, a national, cross-sectional survey performed annually by the U.S. Centers for Disease Control and Prevention.
The researchers specifically investigated whether cannabis use was associated with adverse cardiovascular outcomes among the general adult population, among people who had never smoked tobacco or used e-cigarettes, and among younger adults (defined as men under age 55 and women under age 65) at risk for heart disease. They also factored in the number of days per month that people used cannabis.
The analyses of found:
Any cannabis use (smoked, eaten or vaporized) was independently associated with a higher number of adverse cardiovascular outcomes (coronary heart disease, myocardial infarction and stroke) and with more frequent use (more days per month), the odds of adverse outcomes were even higher. The results were similar after controlling for other cardiovascular risk factors, including tobacco and/or e-cigarette use, alcohol consumption, body mass index, Type 2 diabetes and physical activity.
Both daily and non-daily cannabis users had an increased risk of heart attack compared to non-users; daily cannabis users had 25% higher odds of heart attack compared to non-users.
The odds of stroke for daily cannabis users were 42% higher compared to non-users, with lower risk among those who used cannabis less than daily.
Among younger adults at risk for premature cardiovascular disease (defined as men younger than 55 years old and women younger than 65 years old) cannabis use was significantly associated with 36% higher combined odds of coronary heart disease, heart attack and stroke, regardless of whether or not they also used traditional tobacco products. A separate analysis of a smaller subgroup of these adults who had never smoked tobacco cigarettes or used nicotine e-cigarettes also found a significant association between cannabis use and an increase in the combined odds of coronary heart disease, heart attack and stroke.
“Our sample was large enough that we could investigate the association of cannabis use with cardiovascular outcomes among adults who had never used tobacco cigarettes or e-cigarettes,” Jeffers said. “Cannabis smoke is not all that different from tobacco smoke, except for the psychoactive drug: THC vs. nicotine. Our study shows that smoking cannabis has significant cardiovascular risk risks, just like smoking tobacco. This is particularly important because cannabis use is increasing, and conventional tobacco use is decreasing.”
Study background and details:
Survey participants were ages 18-74, with an average age of 45 years.
About half of the participants self-identified as female. 60.2% self-identified as white adults, 11.6 self-identified as Black adults, 19.3 self-identified as Hispanic adults and 8.9% self-identified as other.
Nearly 90% of adults did not use cannabis at all; 7% used it less than daily; and 4% were daily users. Among current cannabis users, 73.8% reported smoking as the most common form of cannabis consumption. More than 60% of total respondents had never used tobacco cigarettes; 28.6% of daily cannabis users had never used tobacco cigarettes; 44.6% of non-daily cannabis users had never used tobacco cigarettes and 63.9% of participants who did not use cannabis had never used tobacco cigarettes.
The study had several limitations, including that cardiovascular conditions and cannabis use were self-reported, making them potentially subject to recall bias (potential errors in memory); that the authors did not have health data measuring participants’ baseline lipid profile or blood pressure; and the study captured data for only a single point in time for the participants. The authors note that there is a need for prospective cohort studies to examine the association of cannabis use and cardiovascular outcomes while accounting for frequency of cannabis use.
“The findings of this study have very important implications for population health and should be a call to action for all practitioners, as this study adds to the growing literature that cannabis use and cardiovascular disease may be a potentially hazardous combination,” said Robert L. Page II, PharmD, MSPH, FAHA, chair of the volunteer writing group for the 2020 American Heart Association Scientific Statement: Medical Marijuana, Recreational Cannabis, and Cardiovascular Health. Page is professor of clinical pharmacy, medicine and physical medicine at the Skaggs School of Pharmacy and Pharmaceutical Sciences at the University of Colorado School of Medicine in Aurora, Colorado. Page was not involved in this study.
“In the overall population, the study findings are consistent with other studies indicating that daily cannabis use was associated with an increase in heart attack, stroke and the combined endpoint of coronary heart disease, heart attack and stroke,” he said. “As cannabis use continues to grow in legality and access across the U.S., practitioners and clinicians need to remember to assess cannabis use at each patient encounter in order to have a non-judgmental, shared decision conversation about potential cardiovascular risks and ways to reduce those risks.”
A discovery by researchers in Switzerland reveals that the sleeping body also reacts to the external world during sleep, explaining how some information from the sensory environment can affect sleep quality.
A collaboration between University of Liège and University of Fribourg has investigated whether the body is truly disconnected from the external world during sleep.
To do so, they focused on how heartbeat changes when we hear different words during sleep.
They found that relaxing words slowed down cardiac activity as a reflection of deeper sleep and in comparison to neutral words that did not have such a slowing effect.
This discovery, published in the Journal of Sleep Research, sheds new light on brain-heart interactions during sleep.
Matthieu Koroma (postdoctoral researcher), Christina Schmidt and Athena Demertzi (rsesearch) from the GIGA Cyclotron Research Center at ULiège teamed up with colleagues from University of Fribourg led a previous study analysing brain data (electroencephalogram) showing that relaxing words increased deep sleep duration and sleep quality, showing that we can positively influence sleep using meaningful words.
By that time, the authors hypothesised that the brain also remains able to interpret sensory information in a way that makes our body more relaxed after hearing relaxing words during sleep.
In this new study, the authors had the opportunity to analyse cardiac activity to test this hypothesis and found that the heart slows down its activity only after the presentation of relaxing, but not control words.
Markers of both cardiac and brain activity were then compared to disentangle how much they contributed to the modulation of sleep by auditory information.
Cardiac activity has been indeed proposed to directly contribute to the way we perceive the world, but such evidence was so far obtained in wakefulness.
With these results, the ULiège researchers showed that it was also true in sleep, offering a new perspective on the essential role of bodily reactions beyond brain data for our understanding of sleep.
“Most of sleep research focuses on the brain and rarely investigates bodily activity,” says Dr Schmidt.
“We nevertheless hypothesise that the brain and the body are connected even when we cannot fully communicate, including sleep. Both brain and body information need then to be taken into account for a full understanding of how we think and react to our environment,” explains Dr Demertzi.
“We shared freely our methodology following the principles of Open Science hoping that the tools that helped to make this discovery will inspire other researchers to study the role played by the heart in other sleep functions,” Dr Koroma advocates.
This work offers a more comprehensive approach about the modulation of sleep functions by sensory information. By looking into the cardiac responses to sounds, we may, for example, study in the future the role of the body in the way sounds influence emotional processing of memories during sleep.
