Two Years After Catching Covid, Patients Still Risk Getting Sick

The risk of new disease, disability and death remains elevated in some patients as long as two years after catching Covid-19, according to a large study showing the infection’s prolonged heath impact.

(Bloomberg) — The risk of new disease, disability and death remains elevated in some patients as long as two years after catching Covid-19, according to a large study showing the infection’s prolonged heath impact. 

People who were never sick enough to be hospitalized for acute Covid still had a higher risk than uninfected people of developing long Covid-related disorders such as dangerous blood clots, diabetes and lung, gastrointestinal and musculoskeletal disease two years later, according to the study published Monday in the journal Nature Medicine. 

Some 65 million people globally are estimated to be living with so-called post-Covid-19 condition — a number reported to be steadily increasing in the absence of approved treatments and continuing viral spread. The research from the Clinical Epidemiology Center of the Veterans Affairs St. Louis Health Care System in Missouri shows how longterm ailments that afflict Covid survivors add to the disease burden of the pandemic. 

“While many people’s long Covid symptoms improve slowly over time, this can take years, and some symptoms persist even beyond that point,” said Michael Peluso, an assistant professor of medicine at the University of California, San Francisco. “The disability attributed to these post-Covid conditions is sobering.”

Read more: Why Covid’s Aftermath Will Be Felt for a Long Time: QuickTake

Long Covid has been linked to more than 200 symptoms affecting every organ system. Epidemiologist Ziyad Al-Aly and colleagues used the VA’s national databases to compare the incidence of 80 post-acute health problems among 138,818 veterans who survived the first month of a Covid infection during the first year of the pandemic with almost 6 million who weren’t infected during the same period. 

Those who weren’t hospitalized for Covid had an increased risk of developing 31% of the 80 ailments after two years of follow up, compared with non-infected controls, while hospitalized Covid patients had a higher chance of developing 65% of them.

“It’s very clear that people hospitalized during the acute phase of a SARS-CoV-2 infection have a really long and arduous road to recovery,” Al-Aly said in an interview. “They have a significantly higher risk of death, even at two years.”

The increase in mortality risk from Covid-19 wasn’t significant beyond six months for non-hospitalized patients, but remained significantly elevated through the two years for those who had been hospitalized, the study found. Most users of the VA health system are older males, which might limit how applicable the study’s findings are to other groups, the authors said.

Lasting Damage

A severe case of Covid may cause long-lasting alterations to the innate immune system, the body’s first line of defense against pathogens, researchers said Friday in a separate study that points to why the disease can cause persistent inflammation and widespread organ damage. Yet another study published Monday found Covid may trigger new-onset hypertension, especially among hospitalized patients.

Read more: Long Covid’s Immune Effects Seen Linked With High Global Deaths

The VA study measured the burden of disease from long Covid in disability-adjusted life years, or years lost due to disability.

Cumulatively at two years, long Covid contributed a burden of 80.4 disability-adjusted life years for every 1,000 people who caught Covid but weren’t sick enough to be hospitalized, and 642.8 disability-adjusted life years for every 1,000 patients who were hospitalized for acute illness. 

The disability burden “is extremely high, even in the non-hospitalized group, and shows the severity of the impact long Covid is having and will continue to have on society,” said Hannah Davis, who co-founded the Patient-Led Research Collaborative, which studies long Covid, after she developed the condition herself in early 2020.

The “timely and very important analysis” from the VA researchers confirms what doctors have heard from patients in the clinic and in smaller studies, UCSF’s Peluso, who’s also studying Covid’s effects, said in an email. More research is needed on the long-term risks associated with Covid, Peluso said.

“It also reinforces the urgency of figuring out exactly what beyond the initial infection causes these post-acute symptoms and sequelae so that we can identify treatments to return people to their regular health sooner and minimize ongoing disability,” he said.

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