Thread by @ashishkjha

There is something funny happening with COVID hospitalizations

Proportion of COVID pts getting hospitalized falling

A lot

Just recently

My theory?

As hospitals fill up, bar for admission rising

A patient who might have been admitted 4 weeks ago may get sent home now

Thread

So what do I mean "proportion of COVID pts hospitalized falling"?

For months, you could reliably predict new hospitalizations

How?

By taking cases 7 days prior, multiplying by 3.5%

That is

3.5% (1 in 29) of those diagnosed today will be hospitalized about 7 days later

2/10

LOTS of caveats to this formula

Not all states report new hospitalizations (formula takes that into account)

Could build a 10 day lag formula (3.7% hospitalized by 10 days)

All data I report are 7-day moving avgs from @COVID19Tracking

3/10

So let's look at data

On October 15, there are 53K new cases

On Oct 22, you’d expect 1844 hospitalizations (53K*0.035).

What was it actually? 1855

So far so good

4/10

On Nov 1, there are 80K new cases.

On Nov 8, you’d expect 2804 new hospitalizations (80K*0.035)

What was it actually? 2604. A little less. But fine

On Nov 15, there are 146K new cases.

On Nov 22, expect 5111 new hospitalizations (146K*0.035)

But there are only 3670

5/10

I’m ignoring data from last week b/c Thanksgiving messiness though this effect gets much more dramatic

But here’s the fact:

Over much of September and October, you could look at cases today and predict that 3.5% of that number gets hospitalized 7 days later

6/10

But in November, that number starts falling

Initially to 3.2% by Nov 8

By Nov 15, drops to 3.0%

By Nov 22, drops to 2.5%

And by Nov 29, down to 2.1%

So what’s going on? What does this mean?

7/12

May be more testing means we're picking up more cases?

No

% test + is rising from 5.1% (Oct 1) to 12.1% (Nov 15)

So number of cases being missed is climbing

Proportion of pts being admitted from identified cases should be RISING

That 3.5%? Should go up. Instead, its falling

So what’s happening?

What you’d expect – doctors’ threshold for admission is likely going up

In early Oct, with plenty of beds, a COVID patient who is clinically borderline likely gets admitted to ensure they do OK

By Nov 15, beds in short supply, that person likely goes home

Of course, critically ill patients always get admitted

But over time, marginal admissions start disappearing

And as hospitals get fuller, what is defined as “marginal” keeps changing

Until you only admit the sickest folks

10/12

And that’s what appears to be happening

Here's the bottom line:

1 in 3 people who would have been admitted on October 1 aren’t being admitted by November 22

That’s a big change!

And given big rise in test positivity – its likely much higher

11/15

Best guess? we're admitting half the COVID pts we would have admitted October 1

Is this a problem?

If those people don’t need hospitalization, is this bad?

Well, on Oct 1, we would have said that they need hospitalization

So “need” is fluid

But here's the other key issue

The evidence suggests that many of these pts now being sent home will likely do worse at home

Some may be OK -- but others will come back sicker or even die at home

And one more thing

When hospitals fill up, threshold for admission for everything goes up

Everything -- COVID and non-COVID is affected

So borderline admission for heart failure? Person now goes home

Pt with infected leg where you’d prefer IV antibiotics in hospital? They go home with oral antibiotics

This is what is happening in hospitals across America right now

This is not Doctors being cruel

Its that with fewer and fewer beds, bar for hospitalizing anyone is rising

And likely means more people are suffering, getting worse, or even dying at home

All because our hospitals are really full

15/17

So what's the bottom line?

We can see in data that we are likely admitting far fewer COVID patients than we would have just 2 months ago

Likely due to very full hospitals

Because political leaders have politicized mask wearing, social distancing

Its a travesty

16/17

So remember:

Hospitalizations are not static thing

When hospitals get full, by definition you can’t hospitalize all the folks you'd like to hospitalize

And many who would benefit from hospitalization suffer

Because only the very sickest get a bed

Everyone else goes home

Fin