That pesky excess mortality data again
"almost every week for more than 6 mos, [CDC] has calculated that total excess mortality was 50% larger than & often almost twice as large as the number of official #Covid19 deaths, which we tend to regard as the central public health anomaly of the age."
From the associated article:
And though the pattern has continued for three years, there isn’t medical or scientific consensus about what is driving it. Instead, perhaps several hundred thousand “unexpected” deaths have been explained only by loose conjecture. “We’ve got to figure this out,” the University of Minnesota epidemiologist Michael Osterholm told me. “And in order to do that, you’ve got to have that discussion: Wait a minute, this is bigger than people think.”
What are the hypotheses? The first is delayed care — that the pandemic made people postpone treatment for various problems, as doctors and hospitals triaged resources, sending them toward those ill with Covid-19 and away from other issues, and canceled visits and screenings prevented new diagnoses (and therefore treatment).
A second hypothesis is about the indirect effects of pandemic restrictions: not just missed medical care but social isolation, anxiety and unemployment, which can worsen a wide range of conditions, as well as, potentially, suicide and homicide and even car accidents and overdoses, to the extent they each deviated from historical patterns.
A third hypothesis is that Covid-19 infection does harm to the body that can linger after recovery for some people — not just in what is conventionally called long Covid, but also in other ways, by disturbing the function of various organ systems. (Damage to the cardiovascular system has been one particular area of research focus.) “We still don’t really grasp the entire spectrum and breadth of disease yet,” the Yale immunobiologist Akiko Iwasaki told me. “We are still learning.”
Over the last year, papers exploring another theory — involving the risks of these “post-acute sequelae” with reinfection, not just initial infection — have also raised a considerable amount of alarm. Nearly every one of the many experts I spoke to about these papers emphasized their shortcomings, most notably that its authors were looking only at health outcomes among those people who had gone to see a doctor, feeling ill. The effect size was, if real, almost surely much lower than the write-ups suggest, they told me. But nearly every expert also was careful to say that, all things being equal, a reinfection was indeed bad for you, that especially if you were not in great health you’d want to avoid them and that in particular cases a reinfection could certainly contribute to the death of a patient from causes other than classic Covid pneumonia.
Another hypothesis is that Covid infection damages immune function in some patients in a long-lasting way. Here, too, there have been papers published tracing immunological effects, though there has also been a lot of contestation and pushback against — and contextualizing for — narratives of significant and widespread immunological dysfunction.
Of note:
I’ve laid out each of these hypotheses separately, but of course, they are not disentangled. Among the many lessons of the pandemic, for me, has been how much more complicated and baffling disease severity and death are, even beyond the heartbreak it causes — how unpredictable the progression of illness can be, how simplistic it often feels to apply a single cause of death, and how random individual outcomes can seem.
There's actually some really interesting data analysis, if you're into that sort of stuff but in closing:
Where does this leave us? More Americans are still dying than expected, which means at some point the United States may have to reset its expectations for how many will die in a given year at least a bit higher. The country long ago walked away from most mitigation measures beyond vaccination. (And even there, booster uptake has been quite low.) This week, the Biden administration declared it would bring an end to the Covid-19 public health emergency in May, which means that whatever the intuitive implications of these questions, it’s unlikely that, however they are resolved, all that much about pandemic policy will change.
And yet the story of the pandemic looks quite different depending on how we make sense of that excess excess. If we attribute most of those hundreds of thousands of additional deaths to Covid infection — probably the least complicated, Occam’s razor explanation — it raises the direct toll of Covid-19 in the United States to close to 1.5 million. If we attribute it to delayed care and social isolation, it implies some amount of pandemic overreach, and if we attribute it to long Covid and post-acute sequelae it suggests the possibility of an ongoing public health burden. It would be nice to really know.