{"id":5232,"date":"2022-08-01T14:45:06","date_gmt":"2022-08-01T14:45:06","guid":{"rendered":"http:\/\/wp.cov19longhaulfoundation.org\/?p=5232"},"modified":"2022-08-01T14:45:06","modified_gmt":"2022-08-01T14:45:06","slug":"estimates-of-long-covid-are-startlingly-high-heres-how-to-understand-them","status":"publish","type":"post","link":"https:\/\/cov19longhaulfoundation.org\/?p=5232","title":{"rendered":"Estimates of long Covid are startlingly high. Here\u2019s how to understand them"},"content":{"rendered":"\n

Authors: \u00a0Elizabeth Cooney<\/a>\u00a0<\/a>July 2022 STAT<\/p>\n\n\n\n

Think about the adults you know who have had Covid: Does 1 out of every 5 have\u00a0long Covid<\/a>, as the CDC estimates?<\/p>\n\n\n\n

Asking that question should in no way diminish the suffering of people who thought they were done with their infections, only to find their return to well-being<\/a> still beyond reach. But knowing how many people are living with that bitter legacy of Covid-19, and who among working-age adults can\u2019t work or care for their families, is critical to their care and to the health of our society.<\/p>\n\n\n\n

It\u2019s important to remember that long Covid is an evolving umbrella term for an array of symptoms that vary in both number and degree. Some housebound people are assailed by brain fog<\/a> that completely robs them of concentration, while others find memory aids help them get through their workdays. Some former athletes can\u2019t complete a 6-minute walk test, while others can gradually return to activity if they monitor their heart rate. Long Covid clinics<\/a> that adapt techniques from rehabilitation medicine see people eventually get better. In a world transitioning away from bustling downtowns to hybrid work-from-home status, we may not see who\u2019s missing.<\/p>\n\n\n\n

Whatever long Covid\u2019s toll turns out to be, it will be too many people. However you gather or analyze the data, experts told STAT, the proportion of people whose troublesome, sometimes disabling symptoms linger after their acute Covid-19 infections clear is sizable and worrying. It\u2019s the cruelty of large numbers: Even if the actual prevalence of long Covid is much smaller than recent estimates, a small percentage of a large number is a large number.<\/p>\n\n\n\n

And yet, the U.S. has for months been operating in a nearly normal fashion. What could explain this discrepancy between estimates and common experience? It\u2019s eerily similar to the pandemic\u2019s early days, when people asked one another if they knew anyone who had caught the coronavirus, followed more than two years later by the flip side: knowing few people who haven\u2019t been infected and no one who hasn\u2019t been exposed.<\/p>\n\n\n\n

Here are some factors that make the current range of estimates easier to understand.<\/p>\n\n\n\n

First, what are the numbers?<\/h2>\n\n\n\n

That 20% figure, from a recent CDC analysis<\/a> of millions of health records, implies that tens of millions of Americans \u2014 a fifth of people infected with Covid \u2014 have at least one lingering post-infection symptom that is seriously affecting their daily life. Compared to other estimates, like an April meta-analysis<\/a> that puts global long Covid at closer to 50% or a June household survey from CDC <\/a>saying 1 in 3, it\u2019s even on the low side.<\/p>\n\n\n\n

Nathan Praschan, a psychiatry researcher at Massachusetts General Hospital, trusts it, calling the more rigorous CDC study\u2019s epidemiology among the best he\u2019s seen because for over a year it used a control group to tease out Covid effects. Still, he thinks it might have missed some people who don\u2019t show up in medical records. Long Covid is defined by symptoms \u2014 psychiatric disorders and cognitive problems, to name two \u2014 that could make finding care more difficult, as would the same social determinants of health that mean Covid infection is more likely in some populations in the first place. \u201cSo, 1 in 5 may be an underestimate.\u201d<\/p>\n\n\n\n

What about different definitions?<\/h2>\n\n\n\n

CDC\u2019s vs. WHO\u2019s, for instance. The CDC defines long Covid, which it calls Post-Covid Conditions<\/a>, as symptoms lasting four weeks after first infection. The World Health Organization<\/a> starts the clock ticking after three months. Praschan said it makes sense to be inclusive, as in on the earlier side, while data are still being collected to avoid missing important information from these patients.<\/p>\n\n\n\n

There may be differences in the data.<\/h2>\n\n\n\n

While some U.K. studies relied on records a national health system provides, others culled responses from a smartphone app asking people about their post-Covid symptoms. That limits the respondents to people who have smartphones and are also motivated to report how they are feeling.<\/p>\n\n\n\n

The CDC report\u2019s large numbers give power to the analysis, senior epidemiologist Lara Bull-Otterson told STAT. \u201cWhile all studies have limitations, we believe the strengths of the data and the analysis are solid and are also supported by prior research,\u201d she said. \u201cFuture research is always needed to support and expand on the findings of this study.\u201d<\/p>\n\n\n\n

Bruce Levy, chief of pulmonary and critical care medicine at Brigham and Women\u2019s Hospital, doesn\u2019t think the 20% estimate is rock solid, noting how studies have varied widely in the U.S. and in other parts of the world. \u201cEven if it\u2019s in single digits at the end of the day, once a formal case definition and a true prevalence study can be accomplished, it\u2019s still a lot of people. But it\u2019s very hard to pinpoint a solid number.\u201d<\/p>\n\n\n\n

If the size of the CDC study is impressive, the source of the data has limits, epidemiologist Priya Duggal of Johns Hopkins Bloomberg School of Public Health said. Patient records reflect only the people who sought care and whose symptoms were coded in their charts. Such data don\u2019t include people who didn\u2019t have access to health care, didn\u2019t seek it, or gave up, thinking there was no help for their crazy quilt of symptoms.<\/p>\n\n\n\n

\u201cIt doesn\u2019t mean the data\u2019s not right. It doesn\u2019t mean that what we\u2019re looking at isn\u2019t important,\u201d she told STAT. \u201cIt just means that that\u2019s a different group of people that you might be looking at.\u201d<\/p>\n\n\n\n

Even with caveats, she finds the data pretty consistent for a range of 20% to 30% of people experiencing long Covid symptoms \u201cIt\u2019s still a substantial number of people. To me, that\u2019s the take-home point,\u201d she said. \u201cThe second point is that it\u2019s real.\u201d<\/p>\n\n\n\n

Long Covid is a constellation of diseases that manifest differently.<\/h2>\n\n\n\n

Symptoms linked to long Covid hit bodies from head to toe: brain fog, fatigue, shortness of breath, digestive problems, muscle weakness. The symptoms vary in severity and number, depending on the study. But most patients don\u2019t necessarily have all of them. Some patients don\u2019t have debilitating fatigue, but might report persistent digestive problems they didn\u2019t have before getting Covid.<\/p>\n\n\n\n

Some long Covid may be something else.<\/h2>\n\n\n\n

With long Covid so disparate and common, it\u2019s possible that some doctors are misattributing symptoms to long Covid and missing the diagnosis of a different disease. Or, because lifesaving measures in intensive care units can be like a train wreck for the body, it\u2019s hard to tease out the treatment from the disease.<\/p>\n\n\n\n

Some long Covid is hidden to bystanders.<\/h2>\n\n\n\n

\u201cSome of it is going to be visible like, oh, they\u2019re weak, they\u2019re sickly, they can\u2019t walk, they can\u2019t go upstairs,\u201d Duggal said. \u201cThen there\u2019s also long Covid where you have kidney damage now, and the average person walking down the street doesn\u2019t know that.\u201d<\/p>\n\n\n\n

She\u2019s heard people say they don\u2019t know anyone who has long Covid. \u201cI\u2019m like, you probably do.\u201d<\/p>\n\n\n\n

Long Covid isn\u2019t all debilitating.<\/h2>\n\n\n\n

The CDC definitions capture thousands who fit the worst-case image of long Covid: formerly healthy people who can no longer function. But its prevalence estimate also includes anyone reporting at least one symptom, Bruce Walker, director of the Ragon Institute of Massachusetts General Hospital, MIT and Harvard, reminded reporters on a recent call. Estimates may also capture a worsening pre-Covid condition like asthma, an important consideration for the many people with underlying conditions before they caught Covid.<\/p>\n\n\n\n

What\u2019s next?<\/h2>\n\n\n\n

Bull-Otterson of the CDC urged routine screening for long Covid and better defining it so risk factors could be identified and treatments devised. The impact of vaccination and the wild card of variants also need to be understood.<\/p>\n\n\n\n

Long Covid has the potential to widen existing gaps in health, Linda Sprague Martinez of the Boston University School of Social Work said on a video call with reporters, pointing to a map of counties with high case numbers but few long Covid clinics. \u201cWe don\u2019t want to wait,\u201d she said. \u201cGetting ahead of it will be really important for us,\u201d she said.<\/p>\n\n\n\n

OK, what can we say now?<\/h2>\n\n\n\n

Estimates of long Covid will certainly evolve, and perhaps be refined into the systems they affect: cardiopulmonary, digestive, musculoskeletal, or neurological, including autonomic powers that control breathing, heart rate, and other unconscious functions. If, as experts say, there is an inevitability to catching Covid now, or catching it again, long Covid will likely follow in some proportion of cases, disabling some further fraction of those people. Recent studies suggest that Covid infections precede the risk of certain other chronic diseases like type 2 diabetes, but the mechanism isn\u2019t clear. Even if the world wasn\u2019t ready for one pandemic, it has to deal with its aftereffects somehow.<\/p>\n\n\n\n

\u201cWe see people still two years out having long-term symptoms, so if that\u2019s true and people can continue to get infected, this is going to be with us for quite a while,\u201d Duggal said.<\/p>\n\n\n\n

<\/p>\n\n\n\n

<\/p>\n\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

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