Stress may increase heart disease, stroke risk: study

Washington, Feb 21: The fat around arteries may play an important role in keeping the blood vessels healthy, according to a study in rats that may affect how researchers test for treatments related to plaque buildup, as seen in conditions leading to heart attack.

The study, published in the journal Scientific Reports, noted that the fat, known as perivascular adipose tissue, or PVAT, helps arteries let go of muscular tension while under constant strain.

According to the researchers, including Stephanie W. Watts from the Michigan State University in the US, this feature is similar to how the bladder expands to accommodate more liquid, while at the same time keeping it from spilling out.

"In our study, PVAT reduced the tension that blood vessels experience when stretched," Watts said.

"And that's a good thing, because the vessel then expends less energy. It's not under as much stress," she added.

According to Watts and her team, PVAT has largely been ignored by researchers believing its main job was to store lipids and do little more.

Until now, she said, scientists only divided blood vessels into three parts, the innermost layer called the tunica intima, the middle layer called the tunica media, and the outermost layer called the tunica adventitia.

Watts believes PVAT is the fourth layer, which others have called tunica adiposa.

Tunica, she said, meant a membranous sheath enveloping or lining an organ, and adiposa is a synonym for fat.

"For years, we ignored this layer -- in the lab it was thrown out. In the clinic it wasn't imaged. But now we're discovering it may be integral to our blood vessels," Watts said.

"Our finding redefines what the functional blood vessels are, and is part of what can be dysfunctional in diseases that afflict us, including hypertension. We need to pay attention to this layer of a blood vessel because it does far more than we originally thought," she added.

Earlier studies, Watts said, had shown that PVAT plays a role in the functioning of blood vessels, finding that it secretes substances that can cause blood vessels to relax as well as substances that can cause it to contract.

In the current study, the researchers decided to test whether PVAT provides a structural benefit to arteries by assisting the function of stress relaxation.

They tested the thoracic aorta in rats, and found those with intact PVAT had more stress relaxation than those without.

The study revealed that the pieces of artery with surrounding fat had measurably relaxed more than those without.

Watts and her colleagues then tested other arteries, and were able to duplicate the same response.

"It's not something you see only in this particular vessel or this particular species or this particular strain. But that maybe it's a general phenomenon," she said.

The record levels of new daily COVID-19 cases are due to the fact that the pandemic is peaking in a number of big countries at the same time and reflect a change in the virus' global activity, the World Health Organisation said.

At a media briefing on Monday, WHO's emergencies chief Dr Michael Ryan said that the numbers are increasing because the epidemic is developing in a number of populous countries at the same time.

Some countries have attributed their increased caseload to more testing, including India and the US But Ryan dismissed that explanation.

We do not believe this is a testing phenomenon, he said, noting that numerous countries have also noted marked increases in hospital admissions and deaths neither of which cannot be explained by increased testing.

There definitely is a shift in that the virus is now very well established, Ryan said. The epidemic is now peaking or moving towards a peak in a number of large countries.

He added the situation was definitely accelerating in a number of countries, including the US and others in South Asia, the Middle East and Africa.

As the COVID-19 wave sweeps strongly across the country, including in Tamil Nadu, mental health experts say the pandemic has triggered panic attacks among those who tested positive for the virus, causing bouts of depression and even driving some to the brink of suicide.

According to experts, nervousness, fear of contamination, panic attacks, constant reassurance seeking behaviour, sleep disturbance, excessive worry, feelings of helplessness and probability of an economic slowdown are the major factors leading to depression and anxiety among the people.

Potential job losses, financial burden, uncertainty about the future and fears of running out of food and necessities add to the worries.

Online platforms too have seen a growing number of people seeking help for mental health issues, ranging from anxiety and loneliness to concerns over productivity and job loss since the outbreak of COVID-19.

Director of Institute of Mental Health here, Dr R Purna Chandrika said towards April end about 3,632 calls were received and psychiatric counselling was provided to 2,603 callers.

"We have dedicated services at our centres in the districts and the calls meant for government medical college hospitals are routed to the respective institutions," she said.

Due to heavy virus caseloads, making this city the major contributor to the state's tally, the Greater Chennai Corporation too started a free helpline to help residents cope up with stress during the pandemic.

"From the psychological perspective, we don't find a single human being who is not feeling some degree of stress or anxiety due to coronavirus. The intensity and impact varies from person to person," said Lt Col N T Rajan, director of Chennai-based Mastermind Foundation.

The organisation is involved in free counselling throughout India ever since the first case of the deadly virus was reported in the country.

The foundation's recommendation on not to deploy the vulnerable in the police force, especially those above 50 years and women personnel with children below five years for COVID-19 related duty, was accepted and implemented by the Punjab government.

Psychiatrists feel that further worsening situations could lead to severe mental health issues, even triggering suicidal tendencies.

"Further worsening depression may lead to severe mental health issues and suicidal tendencies," said Dr S Senthil Kumar, a psychiatrist.

However, not all of them require medicines, he added.

"The situation is serious. There should be counselling at three stages--on coping with the virus, how to face it if tested positive and how to face life once treated and discharged from the hospital," Rajan said.

Awareness was of paramount importance, he said and warned the pandemic could cause panic attacks while in hospital or drive them to the brink of suicide.

Tamil Nadu, one of the worst affected states with a virus count in excess of 74,000 as of Friday, has witnessed a few instances of suicides allegedly related to COVID-19.

Hari Singh, owner of popular 'Iruttu Kadai' halwa shop in Tirunelveli, allegedly died by committing suicide on Thursday after being tested positive for COVID-19. He was 80.

Earlier in May, two COVID-19 patients in their 50s allegedly committed suicide in separate instances, at the government hospitals they were admitted to for treatment.

In the city corporation limits, a three-member team comprising a psychiatrist, counsellor and a social worker work for the respective zones.

"We direct certain sections of people like those with withdrawal symptoms and people requiring pills, to visit the doctor at their corporation zonal at a specific time, for medicines," a health worker of the civic body said.

Health platform, Lybrate reported an increase of 180 per cent in online patient consultations related to mental health on its platform between March 1 and June 20 across the country.

The largest increase came from Mumbai and Delhi, followed by Pune, Ahmedabad, Chennai and Bengaluru.

The biggest jump was witnessed in the age group of 25 and 45 years.