Why haven't you recovered after getting Yang Kang? Which literature on the study of COVID-19 is reliable?

Recovery takes time, and taking too much rest can cause problems.

Written by | Aspirin 42195m

In January 2023, the journal Nature Reviews Microbiology published a review titled “Long COVID: major findings, mechanisms and recommendations” [1]. When the content was introduced to Chinese media, the title was changed to a shocking title: “Nature’s major review: If no action is taken, long COVID may cause lifelong disability.” This review stated that at least 10%-30% of people who have been infected with the new coronavirus, that is, tested positive, but did not need hospitalization, have long COVID.

At first glance, this journal is good, and it is a subsidiary of the famous Nature. The corresponding author, Dr. Eric Topol, is also very famous. Wikipedia has his own page, which introduces him as an American cardiologist, scientist and writer, and the founder, director and professor of molecular medicine at the Scripps Research Translational Institute.

So, does this mean that the data of 10%-30% is authoritative?

Not necessarily. Let’s analyze it today.

This review actually has several shortcomings:

01 This article's interpretation of COVID-19 is not a consensus in the industry

The definition of long covid has become increasingly clear after three years of the epidemic. As early as 2020, the US CDC proposed that symptoms four weeks after onset would be considered "post-covid sequelae."

Subsequently, the World Health Organization (WHO) summarized an accurate definition of long COVID-19 in October 2021 through a survey of hundreds of long COVID-19 patients, researchers, and experts: three months after COVID-19 infection, symptoms still persist or new symptoms develop, these symptoms have lasted for at least two months, and cannot be explained by other reasons. This is called "post-COVID condition (long COVID-19)" [3]. Most countries now use the WHO definition when studying long COVID-19. Symptoms may be new symptoms after initial recovery from an acute attack of COVID-19, or they may persist from the initial illness. Symptoms may also fluctuate or recur over time.

However, in this review, the authors did not adopt the WHO's established definition of long COVID-19. As long as the symptoms exist after the nucleic acid test turns negative, they are classified as long COVID-19. With this method, the proportion of long COVID-19 will be biased higher and cannot be compared with other relevant literature.

02 This article is not rigorous enough

Dr. Michael Sneller, an infectious disease expert at the NIH who studies COVID-19, pointed out [4] that a suitable control group is necessary for the study of COVID-19. For example, in the early stages of the epidemic, Sneller and others found that 50%-60% of people showed an abnormal lung test after the COVID-19 infection. At first, they were worried that this was a residual symptom of the COVID-19 infection, but further investigations found that even people who were not infected with COVID-19 had such a high proportion of the same abnormal symptoms. This shows that this abnormal lung index is not related to COVID-19 infection.

The most common symptoms after COVID-19 infection are fatigue and insomnia. The stress caused by the three-year pandemic itself can also cause similar symptoms. How can we determine whether fatigue and insomnia are caused by COVID-19 infection or long-term stress? Therefore, we say that the study of COVID-19 must be compared with an appropriate control group in order to draw a more rigorous conclusion.

In addition to the lack of a control group, this review also includes a number of preprint studies and case reports that have not yet been peer-reviewed, such as individual self-reported experiences such as "I took Paxlovid and the COVID-19 disappeared", which makes the article "appear unreliable."

03 The author of the article is not a professional researcher with COVID-19

This is a patient-written article, written by three COVID-19 patients and Dr. Topol. The first author, Hannah E Davis, is an artist. After contracting COVID-19, she founded an organization called Patient-Led Research Collaborative to promote COVID-19 research and called herself a COVID-19 activist [5]. Although the corresponding author, Dr. Eric Topol, is a member of the National Academy of Medicine, he is not a professional researcher on COVID-19.

For comparison, let’s take a look at another meta-analysis of long COVID-19 published in October 2022, titled “Estimated Global Proportions of Individuals With Persistent Fatigue, Cognitive, and Respiratory Symptom Clusters Following Symptomatic COVID-19 in 2020 and 2021”. This article was published in the top medical journal, the Journal of the American Medical Association (JAMA). The results of this analysis showed that among symptomatic non-hospitalized infected people, the proportion of long COVID-19 was 5.7%, far lower than the 10%-30% suggested by the Topol review. At the same time, the JAMA article also wrote: On average, patients recovered in 4 months, which means they recovered one month after being diagnosed with long COVID-19. The proportion of long COVID-19 dropped to less than 0.9% at 12 months [6].

Different from the previous one, this article also has several features:

1. This research project is led by the World Health Organization and involves the joint efforts of dozens of scientists from all over the world who study COVID-19 and statistics.

2. A large number of people were studied. This is the largest meta-analysis of the long-term new crown so far, covering the results of 54 studies around the world and data from two medical databases, involving a total of 1.2 million new crown patients.

3. Rigorous analysis. Many of the authors of the article are biostatisticians. They used Bayesian statistical methods to compare with the control group, removing symptoms caused by other reasons, or reducing data noise, so that they can more clearly see which long-term symptoms are indeed caused by COVID-19 infection.

In short, by comparing these two review articles, we can see that when judging whether an academic document is reliable, we should pay attention to factors such as whether the definition is accurate, whether the method is rigorous, and whether the author is a professional. We cannot just look at the fame of the author or the journal.

After talking about the literature, let's get back to reality. Now many friends still feel a little uncomfortable after turning negative, saying that they have recovered but have not returned to their pre-illness state. Many people also show symptoms such as palpitations and coughs. So how should we view this kind of situation?

First of all, after Yang Kang, the body needs to clean up the mess.

The “Yangkang” mentioned in this article refers to the nucleic acid test result turning negative after being infected with the new coronavirus (positive). If there are still some residual symptoms at this time, it is normal. Our bodies are in direct contact with the new coronavirus for the first time, and it takes some time to clean up the battlefield and start post-war reconstruction. The recovery progress of each person is different. So some friends still have symptoms such as coughing and fatigue from time to time. Don’t worry, these will generally recover gradually. After three months of turning negative, less than 6% of patients still have these symptoms [6].

Second, these symptoms may reflect our bodies' use-it-or-lose-it nature.

After testing positive, did you take a COVID-19 "confinement"? Or did you take a long rest? If you reduce your activity for a long time, you may feel your heartbeat speed up or shortness of breath when you go out to climb stairs or walk faster after you test positive. In fact, this is a decrease in endurance caused by resting too much, which is called deconditioning in medicine. This term refers to the complex physiological changes caused by a period of inactivity, bed rest, or a static lifestyle. The most important effect is a decrease in muscle strength and muscle loss. Fortunately, there is no need to worry about these. As long as you gradually increase your activities, your physical strength will improve and those symptoms will gradually disappear.

It has to be said that many people have learned about these "risks" of COVID-19 infection, thanks in large part to social media and certain experts. On the Internet, the possibility of myocarditis after COVID-19 infection has been exaggerated, scaring many people away from action, and some have even gone to the hospital to request a myocarditis test. Some experts have mistakenly asked everyone to follow the requirements for competitive athletes, asking everyone not to exercise for at least ten days after the test results turn negative [7]. But in fact, most symptoms of shortness of breath and palpitations may just come from the "degeneration" of the body.

This is especially true for patients with residual pulmonary fibrosis. These patients already have poor respiratory function and are easily out of breath when they move, so they often sit or lie down and reduce their activity. But this is a vicious cycle: a long-term sedentary lifestyle will lead to further decline in cardiopulmonary function. Studies have found that the poor respiratory capacity of patients with chronic lung disease may be more due to their physical weakness rather than the severity of their lung disease[8].

In the doctor group, it is common to hear people ask patients with some lung fibrosis whether they should use some kind of medicine or even stem cell therapy? Experts unanimously answer that it is useless. The key is that patients should exercise appropriately and do more lung rehabilitation training.

A small number of people's symptoms after Yang Kang fit the description of a disease called "Postural Tachycardia Syndrome" (POTS). These patients experience dizziness, palpitations, and decreased vision after standing up, and their resting heart rate rises by more than 30 beats per minute within 10 minutes, but their blood pressure does not drop. The current treatment idea for POTS is mainly to maintain adequate water and electrolytes. However, the diagnosis of POTS is not unique to COVID-19 patients. There are many reasons, such as insufficient blood volume, dysfunction, autoimmune problems, etc., which can lead to the above symptoms.

Interestingly, scientists have now discovered that many other viruses, such as influenza virus, can also leave a small number of people with long-term symptoms after infection. These conditions are collectively referred to as "post-viral symptoms."

For example, a study involving 122 medical centers in the United States compared 17,000 COVID-19 patients, 17,000 patients with other common respiratory viral infections, and 17,000 normal people. It found that among the dozens of long-term symptoms that patients experienced between one month and one year after viral infection, only seven were related to COVID-19 infection. These seven symptoms were: palpitations, hair loss, fatigue, chest pain, dyspnea, joint pain, and obesity. Further analysis found that the likelihood of some COVID-19 symptoms was not significantly higher than that of other viral infections [9]. Therefore, we should pay attention to COVID-19, but we should not exaggerate its impact.

Third, we should pay attention not only to physical discomfort, but also to psychological discomfort.

For example, after Yang Kang, do you feel a faster heartbeat, shortness of breath, sweating, and stomach pain? You should know that these symptoms are not necessarily due to physical problems, they are also common symptoms of anxiety.

There is also the "brain fog" that everyone talks about with fear, but you should know that fatigue, anxiety, and depression can affect memory and thinking ability. Is the so-called "brain fog" similar to the common saying "pregnancy makes people stupid for three years"?

The body and mind are one. If mental health is improved, many physical symptoms may be improved. The three-year pandemic has brought mental stress to everyone, which is why the U.S. Preventive Services Task Force, based on the pandemic situation, proposed for the first time in 2022 to screen adolescents for anxiety and depression [10]. Friends who are under great mental stress, anxious, and have long-term sleep problems are best to seek help from psychological professionals.

In short, the residual symptoms after Yang Kang may mean that the body is still recovering, or it may be because we rested too much. In fact, there are not as many people who have the new crown as imagined.

How to deal with the symptoms of COVID-19? There are a few things that are very effective but are easily overlooked by us, that is, eat well, avoid dehydration, get enough sleep, and exercise more. Doing these things well may improve many symptoms.

Please note that there are no nutritional supplements or health products that can help you recover faster, including immunoglobulin. Going to the hospital to check antibodies or do a CT scan has no clinical significance.

However, if the symptoms after the COVID-19 infection are so severe that they affect your daily life, or if they become more severe, or if new symptoms appear, you should still seek medical attention in a timely manner. After all, there are all kinds of other diseases in the world besides COVID-19. If the symptoms after the COVID-19 infection persist for more than three months, it may also be COVID-19, which requires further diagnosis and treatment.

In short, there are many studies on COVID-19, and it is important to read the right articles. Many symptoms after Yangkang are just a reflection of the body's gradual recovery, not an organic problem, and most people will gradually recover.

References

[1] https://www.nature.com/articles/s41579-022-00846-2

[2] https://www.covid.gov/longcovid/definitions

[3] https://www.who.int/europe/news-room/fact-sheets/item/post-covid-19-condition

[4] https://www.science.org/content/article/how-scientists-are-teasing-apart-biology-long-covid

[5] https://me-pedia.org/wiki/Hannah_Davis

[6] https://jamanetwork.com/journals/jama/fullarticle/2797443

[7] https://www.nebraskamed.com/COVID/how-and-when-to-start-exercising-again-after-covid-19

[8] UpToDate: cardiopulmonary exercise testing in the evaluation of unexplained dyspnea

[9] https://academic.oup.com/ofid/article/10/1/ofac683/6953331#392762420

[10] https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/screening-anxiety-children-adolescents

This article is supported by the Science Popularization China Starry Sky Project

Produced by: China Association for Science and Technology Department of Science Popularization

Producer: China Science and Technology Press Co., Ltd., Beijing Zhongke Xinghe Culture Media Co., Ltd.

Produced by: Science Popularization China

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