Sunday, August 23, 2020

Does Covid-19 matter if people would have died anyway?

One thing that appears commonly in reports of deaths due to coronavirus is that those who died were elderly or had underlying health conditions.

Partially based on this, there seem to be a lot of people making or supporting the argument that Covid-19 doesn't matter because it only kills ill or elderly people, and they would have died anyway.

How true is this?

Not true at all, as it happens.

You can easily see this from the ONS figures of excess deaths. Consider the extreme case, if they had died from Covid-19 1 second earlier than they would otherwise, then the deaths would have been reported as normal and there would have been zero excess deaths.

So, the existence of excess deaths indicates that those who died had their lives cut short. But cut short by how much?

If we take the main peak as being in April, then the fact that we're still seeing a significant excess indicates that most of those who died would still be alive now. So, before Covid-19 came along they clearly had those months at least to look forward to.

The term is displaced mortality. Basically, if people die at one point in time, then their death won't happen at a later time. Because everyone dies eventually, all the deaths in the April peak will result in a reduction in the numbers of deaths at the point when they would have died normally. So that peak will translate into a trough at a later date.

Given that we had roughly 60,000 deaths in the UK, and assuming 50 weeks a year to keep the numbers simple, then if the average remaining life expectancy of those who died was 1 year, then we would now be seeing a reduction in the current death rate of about 1,200 a week.

We're not seeing a trough anywhere near that size. If the average remaining life expectancy of those who died was 10 years, then we would now be seeing a reduction in the current death rate of about 120 a week. That would be plausible, given the current numbers.

About the lowest average remaining life expectancy consistent with the current data is something like 4 years - which would lead to a drop in the current death rate of 300 deaths per week. We're not seeing that, but it's something you could fit into the uncertainties.

In conclusion, those who died as a result of Covid-19 weren't at death's door, they would have had years of life to look forward to.