Category: Cardiovascular Disease

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Earlier, Improved MRI Detects ‘Broken-heart’ Syndrome

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A new study from Karolinska Institutet in Sweden suggests that early magnetic resonance imaging (MRI) of the heart can greatly increase the rate of diagnosis of broken-heart syndrome, which can happen when there is no obvious cause in the coronary artery. 

Myocardial infarction is typically caused by a blockage of the coronary artery by a blood clot. However, in up to 10% of all myocardial infarctions, no obvious cause in the coronary artery is found, and so the working diagnosis MINOCA (myocardial infarction with non-obstructive coronary arteries) is given, which can subsequently lead to one of several diagnoses.

Most of these patients are women, many of whom are diagnosed with takotsubo cardiomyopathy (broken-heart syndrome), characterised by reduced heart function that is likely stress-related, presenting the same symptoms as a standard heart attack.

“Around 80 to 90% of broken-heart sufferers are women, and the disease is associated with mental stress,” said principal investigator Per Tornvall, senior physician and professor at the Department of Clinical Science and Education, Stockholm South General Hospital, Karolinska Institutet. “There also seems to be a link to hypersensitivity towards stress caused by low estrogen levels. Unfortunately, research on the investigation and treatment of myocardial infarction is often done on men, while female heart disease is less studied.”

In a prior study with 150 patients, cardiovascular magnetic resonance (CMR) is often done when examining patients with MINOCA. CMR conducted approximately 10 days after onset can result in a diagnosis in under half the patients, normally takotsubo or myocarditis (inflammation of the heart muscle), Now, the same researchers have tested a new, more sensitive CMR technique two to four days after onset on a comparable group of 148 patients. They found that 77% of the patients could be diagnosed: 35% of takotsubo and 17% of myocardial inflammation, compared with 19 and 7%, respectively, in the first study.

“We don’t know how much effect the improved CMR technique has, but the results suggest that with early examination more patients can get a correct diagnosis and therefore the right treatment,” says Professor Tornvall. “The next step is for us to develop the CMR examination with pharmacological stress of the heart. This will enable us to study the smallest of the blood vessels and hopefully find a cause for the 23% who received no diagnosis.”

Source: Medical Xpress

Journal information: Peder Sörensson et al. Early Comprehensive Cardiovascular Magnetic Resonance Imaging in Patients With Myocardial Infarction With Nonobstructive Coronary Arteries, JACC: Cardiovascular Imaging (2021). DOI: 10.1016/j.jcmg.2021.02.021

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Aspirin Plus Blood Thinners Isn’t Always Better

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Collection of pills. Photo by Myriam Zilles on Unsplash

A new study has confirmed that combining two different blood thinners doesn’t necessarily improve outcomes. 

The new publication examined the minimal pros and the serious cons of combining a daily aspirin with a drug from the newer class of direct oral anticoagulants (DOACs) which include apixaban, dabigatran, edoxaban and rivaroxaban.

Patients were taking DOACs to prevent strokes from non-valvular atrial fibrillation or for the treatment of venous thromboembolic disease (deep vein thrombosis or pulmonary embolism). The included patients lacked another reason to take aspirin, such as a recent history of a heart attack or having had a heart valve replacement. One-third of those taking DOACs

“The patients on combination therapy were more likely to have bleeding events but they weren’t less likely to have a blood clot,” said lead author Jordan Schaefer, MD, an assistant professor of internal medicine and a haematologist at the University of Michigan. “Therefore, it’s important that patients ask their doctors if they should be taking aspirin when they are prescribed a direct oral anticoagulant.”

Combination therapy with an anticoagulant and an antiplatelet may be appropriate for people who have had a recent heart attack, recent coronary stent placement or bypass surgery, prior mechanical valve surgery or known peripheral artery disease, among other conditions, according to co-author Geoffrey Barnes, MD, MSc, an assistant professor of internal medicine and a vascular cardiologist at the Michigan Medicine Frankel Cardiovascular Center.

For the others, “combination therapy may not be happening intentionally; rather, the addition of aspirin might get overlooked because it’s not in any one specialist or general care provider’s territory,” Prof Barnes said.

There are many situations where an aspirin and DOAC combination has been insufficiently studied, and Prof Schaefer added that they are planning a larger, lengthier study since there were insufficient blood clots during the study to assess aspirin’s potential benefit.

Profs Schaefer and Barnes had also previously reported increased adverse outcomes for patients receiving both aspirin and warfarin, which is not a DOAC.

Source: Medical Xpress

Journal information: “Adverse Events Associated with the Addition of Aspirin to DOAC Therapy Without a Clear Indication,” JAMA Internal Medicine. DOI: 10.1001/jamainternmed.2021.1197

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Energy Drinks Linked to Heart Failure in Young Man

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In the journal BMJ Case Reports, doctors have warned that heavy energy drink consumption may be linked to heart failure, after treating a 21 year old man who had drunk 2 litres of the drinks every day for 2 years.

This report adds to the growing body of published evidence on, and mounting concerns about, the potential heart harms of these drinks, the authors stated.

The young man in the case report experienced 4 months of progressive shortness of breath on exertion, breathlessness while lying down (orthopnoea), and weight loss before ending up in intensive care.

He habitually drank an average of four 500 ml cans of energy drink every day: each can contains 160 mg of caffeine plus taurine (a protein included in energy drinks for its cytoprotective benefits) and various other ingredients. He said he had been doing this for around 2 years. In the past he had also suffered bouts of indigestion, tremor and palpitations for which he hadn’t sought medical help. In the 3 months before he was admitted to hospital, he had discontinued his university studies because he was feeling so unwell and lethargic.

Testing revealed heart and kidney failure, both of which were severe enough to consider putting him on the list for a dual organ transplant. The kidney failure was due to an unrelated condition.

However, his heart symptoms and function improved significantly with drug treatment and after he cut out energy drinks completely. “However, it is difficult to predict the clinical course of recovery or potential for relapse,” caution the authors.

The authors noted that besides this case report, there have been several others as well as review articles that have highlighted mounting concerns about the potential cardiovascular system harms of energy drinks.

The authors theorised that one factor may be caffeine overstimulating the sympathetic nervous system; energy drinks are also known to increase blood pressure and can trigger heart rhythm abnormalities.

“Clear warnings should be provided about the potential cardiovascular dangers of energy drink consumption in large amounts,” the authors concluded.

“I think there should be more awareness about energy drinks and the effect of their contents,” added the subject of this case report. “I believe they are very addictive and far too accessible to young children.”

Source: Medical Xpress

Journal information: Case report: Energy drink-induced cardiomyopathy, BMJ Case Reports (2021). DOI: 10.1136/bcr-2020-239370

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Black Barbershops with Pharmacist-led Care can Combat Hypertension

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Black and white image of a black man getting a haircut at a barbershop. Credit: BariKive from Pexels.

Black barbershops with pharmacist-led blood pressure (BP) care for their clients, have been shown to be cost effective, with the high initial costs offsetting reduced cardiovascular events later in life.

The study cost simulations were based on the original  Los Angeles Barbershop Blood Pressure Study (LABBPS). In that study, intervention consisted of a trial with men being assigned either to barbershops where barbers encouraged patrons to meet with pharmacists who prescribed drug therapy under an agreement with the participants’ doctors, with the control group being men assigned to barbershops where the barbers only promoted lifestyle modification and physician visits. This intervention resulted in a mean BP drop of 27.0mmHg compared to the control group which fell by 9.3mmHg.

In a 1-year intervention based on costs for the LABBPS, on average, $2356 more per participant than the controls and was associated with a gain of 0.06 quality-adjusted life years (QALYs) over a 10-year horizon, according to Brandon Bellows, PharmD, MS, of Columbia University in New York City, and colleagues.

Thus, in computer simulations,  the LABBPS intervention was associated with 10-year projected total healthcare costs averaging $42 717 per QALY gained, reported the researchers.

“One concern raised as a potential barrier to widespread LABBPS implementation is the specialty training of clinical pharmacists. In this analysis, the cost of specialty training and certification was included; the results suggest that long-term health benefits and avoided healthcare costs of the LABBPS offset these upfront training costs,” the researchers wrote.

The team reported that the cost effectiveness of the intervention could be increased under various various scenarios:

  • Only using generic drugs: $17 162 per QALY gained
  • Shortening intervention to 26 weeks: $18 300 per QALY gained
  • Implementing optimal savings from less time spent on intervention tasks, lower equipment costs, only using generics, and no participant incentive costs: intervention becomes dominant (both less expensive and more effective than control)

However, if pharmacists were less likely to intensify antihypertensive medications when systolic BP was ≥ 150 mm Hg, or if pharmacists took longer to get to the barbershops, the cost of the LABBPS intervention would exceed $50 000 per QALY gained.

“Hypertension care delivered by clinical pharmacists in Black barbershops is a highly cost-effective way to improve BP control in Black men,” the authors concluded.  

The LABBPS has received praise for demonstrating that Black men with uncontrolled hypertension had better BP control after 6 months with barbershop visits by specialty pharmacists than with regular physician visits. Extending the intervention to 1 year did not change the results.

Researchers previously reported that a telemedicine component could bring down cost and maintain efficiency of the LABBPS program.

“Hypertension prevalence remains higher among non-Hispanic Black men than in any other racial or ethnic group in the US. Hypertension awareness and treatment have plateaued in the US since 2010, and Black men continue to have worse BP control and higher hypertension-related cardiovascular disease mortality rates compared with other groups,” the investigators wrote.

The researchers assumed that after the one-year intervention period, processes of hypertension care management returned to standard care, which was a major limitation of the study.

“These findings may also be somewhat limited in scope as a healthcare sector perspective was used, which only considers direct healthcare costs, rather than a societal perspective, which may include indirect costs such as improvements in productivity,” noted Bellows and co-authors. “Finally, cost-effectiveness estimated for the LABBPS may not be generalizable to other U.S. communities, as it was specific to Los Angeles County and was driven in part by the high underlying risk of cardiovascular disease in Black men.”

Source: MedPage Today

Journal information: Bryant KB, et al “Cost-effectiveness of hypertension treatment by pharmacists in black barbershops” Circulation 2021; DOI: 10.1161/CIRCULATIONAHA.120.051683.

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Study Upends Preconceptions of Blood Pressure Management

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New research could change how doctors treat some patients with hypertension, as they find that low diastolic blood pressure can be benign in blood pressure management.

The study by researchers at NUI Galway, Johns Hopkins University and Harvard Medical School found no evidence that diastolic blood pressure can be harmful to patients when reduced to levels that were previously considered to be too low. High blood pressure, or hypertension, affects a quarter of men and a fifth of women. Blood pressure medications reduce both systolic and diastolic values.

Lead researcher Bill McEvoy, Professor of Preventive Cardiology at NUI Galway and a Consultant Cardiologist at University Hospital Galway, said the findings have the potential to immediately influence the clinical care of patients. The study was published in the prestigious journal Circulation.

“We now have detailed research based on genetics that provides doctors with much-needed clarity on how to treat patients who have a pattern of high systolic values – the top reading for blood pressure – but low values for the diastolic, or bottom, reading,” said Bill McEvoy, Professor of Preventive Cardiology at NUI Galway. “This type of blood pressure pattern is often seen in older adults. Old studies using less reliable research methods suggested that the risk for a heart attack began to increase when diastolic blood pressure was below 70 or above 90. Therefore, it was presumed there was a sweet-spot for the diastolic reading.”

Hypertension is a major contributor to mortality around the world, linked to heart attacks as well as brain, kidney and other diseases. It has also emerged as a risk factor for COVID severity and mortality.

Using new technologies that take into account genetic information that is unbiased, which was not the case with prior observational studies, Professor McEvoy and the international research team analysed genetic and survival data from more than 47 000 patients worldwide.

The researchers found that there is apparently no lower limit of normal for diastolic blood pressure and no evidence in this genetic analysis that diastolic blood pressure can be too low. They also found no genetic evidence of increased risk of heart disease when a patient’s diastolic blood pressure reading is as low as 50. The findings confirmed that values of the top, systolic, blood pressure reading above 120 increased the risk of heart disease and stroke. 

“Because doctors often focus on keeping the bottom blood pressure reading in the 70-90 range, they may have been undertreating some adults with persistently high systolic blood pressure,” Prof McEvoy explained. “The findings of this study free up doctors to treat the systolic value when it is elevated and to not worry about the diastolic blood pressure falling too low.

“My advice now to GPs is to treat their patients with high blood pressure to a systolic level of between 100-130mmHg, where possible and without side effects, and to not worry about the diastolic blood pressure value.” 

Source: News-Medical.Net

Journal information: Arvanitis, M., et al. (2021) Linear and Nonlinear Mendelian Randomization Analyses of the Association Between Diastolic Blood Pressure and Cardiovascular Events. Circulation. doi.org/10.1161/CIRCULATIONAHA.120.049819.

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New Clinical Practice Review for Diabetes Drugs

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A new clinical practice review article in The New England Journal of Medicine (NEJM) collates the latest trial results and guidelines into a systematic approach for the treatment of patients with diabetes and a risk of cardiovascular disease. It is the journal’s first such review by the journal in nearly a decade.

Clinical practice reviews differ from research studies in that they present a common clinical problem along with the evidence supporting various treatment strategies and review the guidelines. Finally, the author offers clinical recommendations for optimising patient care.

Compared to those without the disease, people with type 2 diabetes have over double the risk of developing atherosclerotic cardiovascular disease and heart failure. In South Africa, 10.1% of the population over 15 is believed to have type 2 diabetes, and is expected to cost the health sector R35.1 billion by 2030. 

The NEJM article by Johns Hopkins Medicine endocrinologist and associate professor Rita Rastogi Kalyani, MD, presents an up-to-date approach for health care providers when choosing among glucose-lowering therapies for their patients with diabetes, particularly to reduce the risk of cardiovascular disease. Dr Kalyani reviews the cardiovascular benefits and risks of the most common diabetes drugs currently available on the US market.

“We’ve seen a major shift in diabetes care over the past few years,” said Dr Kalyani. “We now have tools to better understand how to reduce both microvascular and macrovascular complications in people with type 2 diabetes.”

Dr Kalyani highlighted specific agents in two newer drug classes, which she showed are beneficial for patients with diabetes who already show signs of heart or blood vessel disease.

The glucagon-like peptide 1 (GLP-1) receptor agonists liraglutide, injectable semaglutide and dulaglutide increase insulin production from the body, particularly after meals.

Sodium glucose cotransporter 2 (SGLT2) inhibitors empagliflozin and canagliflozin reduce the amount of glucose the body re-absorbs through urine. 

All of these are effective in risk reduction for major cardiovascular events, such as heart attack or stroke. The SGLT2 inhibitor dapagliflozin is effective in reducing the risk of hospitalisation for heart failure.

“After metformin, which is widely considered the initial drug treatment for type 2 diabetes, specific drugs in the GLP-1 receptor agonist and SGLT2 inhibitor classes with demonstrated cardiovascular benefit should be considered as additional medications for patients who already have cardiovascular disease. This should be done irrespective of whether their A1C level is at target to reduce the risk of future cardiovascular events,” advised Kalyani.

The A1C test measures the average percentage of glucose in a person’s haemoglobin over the span of several months. Healthy A1C levels are below 5.7%, and typically, A1C levels over 6.5% indicate diabetes.

Newer drugs tend to be costlier, and long-term effects are unknown. Also, prior to 2008, the US Food and Drug Administration did not require large outcome trials for drugs after they were released onto the market, meaning that older drugs have less certain cardiovascular outcomes, said Dr Kalyani.
The NEJM article details specific drugs that offer additional benefits for patients with diabetes who have conditions such as multiple cardiovascular disease risk factors, heart failure and chronic kidney disease.

“Some agents such as dulaglutide and dapagliflozin also have demonstrated cardiovascular benefit in patients with multiple cardiovascular risk factors,” said Dr Kalyani.

Further, specific SGLT2 inhibitors can be beneficial for patients who have heart failure with reduced ejection fraction, as well for patients with chronic kidney disease.

Comprehensive drug tables in the article take into account factors for consideration in clinical practice when choosing a glucose-lowering drug for patients with type 2 diabetes, including A1C-lowering efficacy, route and frequency of administration, cost, impacts weight, hypoglycaemia risk, side effects and clinical benefits.

“Health care providers in primary care, endocrinology, cardiology and nephrology are now prescribing these newer glucose-lowering drugs for their patients,” Dr Kalyani said. “Diabetes care will need to be increasingly collaborative in the future and, at its core, remain patient-centered.”

Source: Medical Xpress

Journal information: Rita R. Kalyani et al. Glucose-Lowering Drugs to Reduce Cardiovascular Risk in Type 2 Diabetes, New England Journal of Medicine (2021). DOI: 10.1056/NEJMcp2000280

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New Exosome-coated Shunt Boosts Blood Vessel Recovery

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Researchers have developed a new exosome-coated shunt that enhances tissue repair and heals vascular injury without narrowing the blood vessel, while also providing regenerative stem cell-derived therapy to ischaemic (blood starved) tissue.

A metal stent is often used in angioplasty to reinforce arterial walls and prevent collapse once the blockage is removed. However, placing the stent usually injures the blood vessel wall, stimulating smooth muscle cells to proliferate and migrate to the site to repair the injury. What results is restenosis, a re-narrowing of the blood vessel previously opened by angioplasty.
“The inflammatory response that stents cause can decrease their benefit,” said corresponding author Ke Cheng. “Ideally, if we could stop smooth muscle cells from over-reacting and proliferating, but recruit endothelial cells to cover the stent, it would mitigate the inflammatory response and prevent restenosis.” Cheng is the Randall B. Terry Jr. Distinguished Professor in Regenerative Medicine at NC State and a professor in the NC State/UNC-Chapel Hill Joint Department of Biomedical Engineering.

There are drug-eluting stents currently in use coated with drugs that ihibit cell proliferation, but these anti-proliferative drugs also delay the desired outcome of endothelial cells covering the stent.

To solve this, Prof Cheng and his team developed a stent coating made up of exosomes derived from mesenchymal stem cells. Exosomes are tiny nano-sized sacs secreted by most cell types. As the exosome surfaces are similar to cell membranes, they ‘camouflage’ the stent to fool smooth muscle cells and the body’s immune system. The exosomes also encourage endothelial cells to cover the stent and, in the case of injury, travel downstream to the site to promote tissue repair.

In order to prevent the therapy running out early, the stent releases exosomes when it encounters reactive oxygen species (ROS) – which are more prevalent during an inflammatory response.

“Think of it as a smart release function for the exosomes,” Cheng says. “Ischemic reperfusion injuries, which occur when blood flow is diminished and then reestablished, create a lot of ROS. Let’s say the heart is damaged by ischemia. The enhanced ROS will trigger the release of the exosomes on the stent, and regenerative therapy will travel through the blood vessel to the site of the injury.”

Using in vitro testing, they found that in the presence of ROS, the exosomes released up to 60% of their secretions within 48 hours after the injury.

The researchers used a rat model of ischaemic injury to compare their exosome-eluting stent (EES) to both a bare metal stent (BMS) and a drug-eluting stent (DES). They found that in comparison to the BMS, their stent performed better in both reducing stenosis and stimulating 0endothelial coverage.

While the DES and EES were similar in preventing restenosis, the EES caused lesser vessel wall injury and had better endothelial coverage overall. Additionally, the exosomes released from EES promoted muscle regeneration in rats with hind limb ischaemia. Next, the researchers plan testing of the system in a larger animal model, eventually leading to clinical trials.

“This bioactive stent promotes vascular healing and ischaemic repair, and a patient wouldn’t need additional procedures for regenerative therapy after the stent is in place. The stent is the perfect carrier for exosomes, and the exosomes make the stent safer and more potent in tissue repair,” said Prof Cheng.

Source: News-Medical.Net

Journal information: Hu, S., et al. (2021) Reopen and Regenerate: Exosome-Coated Stent Heals Vascular Injury, Repairs Damaged Tissue. Nature Biomedical Engineering. doi.org/10.1038/s41551-021-00705-0.

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Antihypertensive Drugs Not Linked to Cancer Risk

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A review of 33 clinical studies  showed that antihypertensive drugs did not have a consistent association with cancer risk.

Patients treated with any of five different classes of antihypertensive drugs had essentially the same cancer risk as those receiving placebo. Comparisons of each antihypertensive class against all the others showed no association with an increased risk of cancer, save for calcium channel blockers (CCBs), which had only a modestly higher risk versus the other drug classes (HR 1.06, 95% CI 1.01-1.11).

The data do not conclude the issue, since some comparisons had insufficient data to exclude the possibility of excess cancer risk, reported Kazem Rahimi, DM, of the University of Oxford in England, and colleagues in Lancet Oncology.

“Our study has addressed an ongoing controversy about the safety of blood pressure-lowering medication with respect to cancer risk, using the largest sample of individual-level randomized evidence on blood pressure-lowering treatment to date, to our knowledge,” they wrote. “The main implication of our study is that patients using antihypertensive medication should continue to take their medications because concerns about increased cancer risk seem to be unfounded.”

The author of an accompanying commentary noted that the findings could have been due to chance. The number of trials per drug class varied greatly, and small sample sizes were used in analyses by type of cancer.

“Taken together, these limitations raise a more fundamental question about how the findings of randomised controlled trials should be interpreted,” wrote Laurent Azoulay, PhD, of McGill University in Montreal.

Randomised trials are the “gold standard” for assessing drug efficacy, but are not typically designed to assess safety, he continued. This is especially important for outcomes like cancer, which have a delayed onset. Since the median follow-up was only 4.2 years , “a potential association between cancer and the long-term use of antihypertensive drugs cannot be ruled out.”

“Such analyses are necessary to understand the short-term effects of these drugs on cancer incidence,” Azoulay concluded. “However, moving forward, these studies will need to be complemented with well-designed, real-world studies in heterogeneous patient populations who are followed up for extended periods of time to fully understand their carcinogenic potential.”

Several meta-analyses have yielded conflicting evidence, Rahimi and colleagues stated. The Blood Pressure Lowering Treatment Trialists’ Collaboration (BPLTTC) is the world’s largest individual patient-level data on blood pressure-lowering trials, and data from this formed the basis for the meta-analysis.

The authors identified 33 trials for inclusion in the meta-analysis, which comprised 260 447 patients with available data on cancer outcomes. CCBs were the antihypertensive class most commonly represented in the trials (n=19), followed by ACE inhibitors (15), angiotensin-receptor blockers (ARBs, 11), thiazide diuretics (six), and beta-blockers (five). Median follow-up ranged from 4 to 5 years across the trials, grouped by drug class.

Patient age ranged between 64 and 68 by drug class, and pretreatment systolic blood pressure ranged from 147mm Hg (ACE inhibitors) to 166mm Hg (beta-blockers).

Across the five classes of antihypertensive drugs, individual comparisons for cancer risk versus the other drug classes yielded only a maximum hazard ratio of 1.06 for CCBs.

“We found no consistent evidence that antihypertensive medication use had any effect on cancer risk,” the authors stated.

Source: MedPage Today

Journal information 1: Copland E, et al “Antihypertensive treatment and risk of cancer: An individual participant data meta-analysis” Lancet Oncol 2021; DOI: 10.1016/S1470-2045(21)00033-4.

Journal information 2: Azoulay L “Elucidating the association between antihypertensive drugs and cancer: A need for real-world studies” Lancet Oncol 2021; DOI: 10.1016/S1470-2045(21)00085-1.

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Study Reveals Additional Pathway From Brain to Cardiovascular System

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Researchers at  University of Tsukuba in Japan have uncovered a previously unknown pathway from the brain to the cardiovascular system.

Though the cardiovascular system has a degree of autonomy to allow their independent functioning from the brain, the brain still has some control over it in order to respond to life-threatening situations. This control is exerted through the sympathetic and parasympathetic systems of the autonomic nervous system.

“From an evolutionary standpoint, the brain has had an incredibly important function in protecting the individual from predators,” says the lead author of the study Professor Tadachika Koganezawa. “But even in the absence of predators, our bodies react to stressful situations. In this study, we wanted to determine how the brain regulated the cardiovascular system via the autonomic nervous system.”

Located deep within the brain, the lateral habenula (LHb) has been known to elicit strong behavioural and cardiovascular responses to stressful events. But how it did so was still unclear. so to find out the researchers electrically stimulated the LHb in rats. This resulted in bradycardia and increased mean arterial pressure (MAP). The researchers then turned off the parasympathetic system by means of cutting the main parasympathetic nerve, the vagal nerve, or using a drug to antagonise it. 
Though this suppressed the LHb’s effect on the heart rate, the MAP was unchanged. Antagonising the sympathetic system had the opposite effect—decreasing the MAP but there was no effect on the heart rate.

To understand the mechanism by which the LHb elicits these cardiovascular responses, the researchers focused on the neurotransmitter serotonin, which plays an important role in the brain in modulating mood, cognition, and memory, among other functions.

While blocking all serotonin receptors significantly reduced the LHb’s effect on both the MAP and heart rate, the researchers found that specific subtypes of serotonin receptors were particularly involved in the process.

“These are striking results that show how the lateral habenula controls the cardiovascular system,” said study author Professor Masayuki Matsumoto , University of Tsukuba. “Our results demonstrate the mechanism of a neural circuit that plays an important role in stress-induced behavioral responses.”

Source: News-Medical.Net

Journal information: Doan, T. H., et al. (2021) Lateral Habenula Regulates Cardiovascular Autonomic Responses via the Serotonergic System in Rats. Frontiers in Neuroscience. doi.org/10.3389/fnins.2021.655617.

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Recurrence Risk of Heart Attack is Increased by Long Hours

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Photo of neon-lit heart by Leon Collett, via Unsplash.

For heart attack survivors, the risk of recurrent coronary heart disease is increased by working long hours.

Heart attack survivors who working 55+ hours per week were at higher risk of recurrent coronary heart disease (CHD) events (ie, myocardial infarction [MI] or unstable angina) over 6 years compared with people working a more standard 35-40 hours a week (adjusted HR 1.67). This included adjustment for sociodemographics, lifestyle-related risk factors, clinical risk factors, work environment factors, and personality factors.

“These results showed a linear risk increase after 40 h/week and a stronger effect after the first 4 years of follow-up and when long working hours are combined with job strain,” wrote Xavier Trudel, PhD, of CHU de Québec-Laval University Research Centre in Quebec City, and colleagues. 
The researchers suggested secondary interventions in curbing working hours among patients at risk of CHD recurrence.

In an accompanying editorial, Jian Li, MD, PhD, of UCLA, and Johannes Siegrist, PhD, of Heinrich-Heine-University, concurred: A “short standardized assessment of working time and stressful working conditions among economically active cardiac patients would enrich physicians’ awareness of patients’ needs and inform medical decision making.”

“With the transformation of the modern work due to technological advances and economic globalisation, an increase in work load and an extension of irregular, nonstandard forms of employment, including working from home, were reported, aggravating the control and prevention of long working hours,” Drs Li and Siegrist wrote.

They urged cardiac rehabilitation programmes to offer “training skills of coping with stressful demands and of strengthening resilience and relaxation” and involving occupational health services to develop return-to-work plans.

When cardiac disease patients return to work, their workplaces will need to adopt tailored, programs to retain the workers and manage disease, Drs Li and Siegrist added.

The prospective cohort study included 967 MI survivors under age 60, of whom 205 had a recurrent CHD event over follow-up averaging 5.9 years.Men and people in their 40s and 50s were most likely to be working long hours after an MI. Job strain, defined as a combination of high psychological demands and low decision latitude at work, was measured with a questionnaire.

Work hours for each participant were assessed only once, at about 6 weeks after returning to work. “Some patients could have changed exposure during follow-up, leading to potential nondifferential misclassification and to an underestimation of the true effect,” Trudel’s group acknowledged.

The observational study was limited by only one tenth of participants being women, limiting generalisability, and by unknown confounding variables.

“In conclusion, the study by Trudel et al. provides a new piece of research evidence that work-related factors play an important role in CHD prognosis,” Drs Li and Siegrist wrote. “Occupational health services are urgently needed to be incorporated into cardiac rehabilitation programs and secondary prevention of CHD.”

Source: MedPage Today

Journal article information: Trudel X, et al “Long working hours and risk of recurrent coronary events” J Am Coll Cardiol 2021; DOI: 10.1016/j.jacc.2021.02.012.

Editorial information: Li J, Siegrist J “Occupational risks of recurrent coronary heart disease” J Am Coll Cardiol 2021; DOI: 10.1016/j.jacc.2021.02.020.