Writing in The Atlantic, Adam Gaffney, a pulmonary and critical care physician and an assistant professor at Harvard Medical School, explains why more research is needed to understand who is suffering from long Covid and why, as well as what providers can do to help patients who are struggling with long-term symptoms.

What exactly is long Covid?

According to Gaffney, "[q]uite simply, long COVID isn't any one thing." Instead, it is a wide spectrum of conditions that "fall into a few rough (and sometimes overlapping) categories," he writes.

The first category of long Covid consists of a combination of organ damage, severe physical debilitation, and poor mental health caused by severe pneumonia and the resulting critical illness. At the end of 2021, there were more than 7 million Covid-19 hospitalizations in the United States, which suggests that millions of people may now have damaged lungs or other complications from severe illness.

A second category of long Covid occurs when an individual develops a new medical condition, such as heart disease, diabetes, asthma, or kidney failure, after a mild Covid-19 infection. According to Gaffney, similar situations have also occurred after other common respiratory virus infections, particularly influenza.

However, because cases of mild Covid-19 are so common, measuring the prevalence of this type of long Covid is difficult. "Well-controlled investigations are needed to disentangle causation and correlation, particularly because social disadvantage is associated both with COVID exposure and illnesses of basically every organ system," Gaffney writes.

A third category of long Covid consists of long-lasting respiratory symptoms, but they are not associated with lung damage, severe illness, or a new medical condition, such as heart attack. In general, shortness of breath, chest pain, and other similar symptoms are common even months after pneumonia or another non-Covid upper respiratory infections.

However, even with these categories, "none of these may be what most people think of when long COVID is invoked," Gaffney writes. Instead, some people may consider long Covid a chronic illness with "a complex of numerous unexplained, potentially debilitating symptoms," include severe fatigue, brain fog, shortness of breath, gastrointestinal problems, and much more.

Overall, "[t]easing apart which kind of long COVID a person has is important, both to advance our understanding of the illness and to best care for people," Gaffney writes.

How 'psychosocial strain' could contribute to long Covid

Currently, the exact cause of long Covid symptoms is unknown, but researchers have posited several theories so far, including damage to blood vessels, a chronic coronavirus infection, or an autoimmune disorder.

However, a recent study from NIH suggests that some long Covid patients have "effectively no substantive differences in markers of inflammation or immune activation, in objective neurocognitive testing, or in heart, lung, liver, or kidney function," even as they continue to suffer from various symptoms.

For this group of patients, Gaffney suggests that "psychosocial strain" may be a contributing factor to their symptoms. For example, several studies have shown that severe depression can lead to severe physical symptoms, such as fatigue and brain frog, and has been linked to having had Covid-19.

In addition, a recent study published in JAMA Psychiatry found that prior psychosocial distress, such as depression, anxiety, or loneliness, was associated with a 30% to 50% increased risk of long Covid among individuals who were later infected.

"The reality … is that psychosocial strain is an important driver of physical symptoms and suffering—one that clinicians should treat with empathy," Gaffney writes. "All suffering, after all, is ultimately produced and perceived in one place: our brain."

How to support long Covid patients now

Although there is still much that scientists do not understand about long Covid, "we can take steps—both among clinicians and as a society—to improve lives now," Gaffney writes.

For example, increased social supports would be beneficial for long Covid patients who cannot work or cannot afford expensive medical care. This includes making it easier for people to qualify for disability assistance if they need it and making specialized rehabilitative care more accessible to patients with certain symptoms like shortness of breath or reduced exercise tolerance.

Gaffney said that health care professionals should have more education on Covid-19-related issues to improve care and reduce stigma against patients with all forms of the disease.

"Doctors and scientists still have much to learn about symptoms that continue—or first turn up—months or weeks after an initial COVID infection," Gaffney writes. "What's clear today is that long COVID can be many different things. That may confound our efforts to categorize it and discuss its implications, but the sheer variety should not get in the way of care for all who are suffering."(Gaffney, The Atlantic, 10/5)