Covid Scotland: Are excess death rates really soaring?

In recent months, there has been a lot of interest in excess deaths - particularly in December when winter viruses such as flu surged back after a two-year hiatus and scenes of ambulances stacked outside A&E departments vividly illustrated an NHS in gridlock.

Indeed, according to provisional data published this week by the National Records of Scotland, there were 4,646 “excess deaths” during 2022, and 606 in January and February 2023.

In other words, more people died than expected, when compared to previous years.

In the case of 2022, that meant there were 4,646 more deaths - from all causes - than there were per year, on average, from 2016-2019 and 2021.

The five-year average for 2023 is based on a comparison with 2017-19 plus 2021 and 2022. Statisticians exclude 2020 due to the highly unusual surge in mortality caused by Covid.

READ MORE: A&E delays and excess deaths - is this the new normal? 

On the basis of these excess death counts, we can say that mortality in Scotland was 7.9 per cent higher than the five-year average in 2022, and 5.5% higher than the five-year average in the first two months of 2023.

At face value, that paints a pretty shocking picture of a country whose health - and health service - has taken a fairly dramatic turn for the worse.

Undoubtedly, such a divergence from previous trends is worthy of note.

From 2013 to 2019 - with the exception of a couple of winter-related spikes in 2014/15 and 2017/18 - the number of deaths recorded largely overlapped with the five-year averages.

Before 2020, the number of deaths registered each month in Scotland (purple line) tended to be similar to the five-year average (dotted line); since 2020 the number of deaths has tended to be higher than the five-year average (Image: National Records of Scotland)

From 2020 onwards, however, the two measures drifted apart as first Covid and then the longer-term effects of the virus, and all the measures taken to suppress it, took their toll.

That said, tracking excess deaths by number alone is a fairly blunt tool.

Statisticians prefer to count them using something called the ‘age-standardised mortality rate’ (ASMR).

This has two key effects: it adjusts for the size of the population, and for the age structure of the population, which means that - despite changing demographics over time - mortality patterns in Scotland can be validly compared against both previous years and other European countries (the standardisation used is against the 2013 European Standard Population).

This data was made available for the first time this week by National Records of Scotland, and it reveals a somewhat different picture.

Changes in excess deaths over time by ASMR (solid purple line) compared to number of deaths (broken purple line) (Image: NRS)

For 2022 as a whole, the excess death rate (ASMR) was 1.5% higher than the five year average.

Put another way, there were 212 more deaths per 100,000 people than would have been expected.

By way of comparison, excess deaths in England were up 6.3% in 2022, but measured by ASMR the mortality rate was actually 0.7% lower than expected.

READ MORE: Why are Scotland's cancer deaths lower in 2022 than before the pandemic

The same statistics can also be used to look at trends for different types of disease.

Under the umbrella of ‘circulatory’ deaths, which includes heart disease, strokes, haemorrhages and blood clots, the figures show that there were 1,167 excess deaths in Scotland during 2022.

The number of deaths from circulatory causes was up 7.7% on the five-year average.

But if ASMR is used instead, the trend is less dramatic: 33 extra circulatory deaths per 100,000 in 2022, or an increase in the death rate of 0.9% compared to the five-year average.

What about cancer deaths?

The impact of the pandemic, from screening pauses to growing bottlenecks for diagnostics scans and tests, had been widely tipped to store up a “cancer timebomb”.

For now, at least, that isn’t backed up by the statistics.

It is possible that people are dying of undetected cancers, however, or that it is simply too early to see the effect.

According to NRS, there were 134 excess cancer deaths in 2022 - an increase of 0.8% on the five-year average.

Most of this uptick occurred towards the end of the year, signalling a slight reverse after months of lower-than-normal cancer deaths.

Based on ASMR, however, Scotland’s cancer mortality in 2022 was 4.9% lower than the five-year average with 182 fewer deaths than expected per 100,000.

It might seem odd that there can be such a gulf between excess deaths by number and by rate, but it is normal to have a gap during a period when the population is changing.

Explaining, one NRS statistician said: “We calculate excess deaths by comparing to the last five years, so we’re comparing to a time when the population was smaller and younger than it is now.

"We might therefore expect to have more deaths now than we did in the past.

“As the excess deaths figure calculated on the ASMR removes the effects of the population changes, this is why we see a gap.

“The size of the gap will be driven by how much the population has changed over recent years.

"So if our population hadn’t changed at all (in terms of size or age-composition) we would expect the two excess deaths measures to show similar results.”

They added that while the ASMR measure is “more reliable”, counting excess deaths by number “is easier to understand” - hence why it tends to be used to communicate with the public.

READ MORE: What can Scotland learn from Ireland's surge in life expectancy?

Of course, the ripple effects of the pandemic on health will be felt for years, if not probably decades, to come.

Life expectancy - another shorthand for population health - is already falling in Scotland, and that decline may get steeper in the years ahead as the repercussions austerity, Covid, and the cost-of-living play out.

Also important are health inequalities, which are widening.

By 2021, people living in Scotland's poorest communities were 56 per cent more likely to die before the age of 75 than the Scottish average (Image: Scottish Government)

On Tuesday, a Scottish Government report found that the difference in premature mortality rates (dying before the age of 75) between Scots living in the most deprived communities versus the Scottish average is wider now than at any point since 1997.

If there one clear legacy from the pandemic it is this: that the poorest are getting sicker, faster, than those who can afford to buy their way to quicker treatment and better health.