Non-COVID-19 excess deaths by cause
Excess deaths by underlying cause and area deprivation 26 August 2020

Main points

A sizeable proportion of the excess deaths[1] in Scotland during the COVID-19 pandemic have not been coded as being directly due to COVID-19[2]. Here we summarise our analysis of which underlying causes have contributed to these non-COVID-19 excess deaths: our detailed report can be found on the website.

Using provisional death register data from National Records of Scotland we calculated the excess in age-sex standardised rates of death from key underlying causes[3] during the 14 week period from the registration of the first COVID-19 deaths in Scotland until numbers of deaths from all causes had returned to normal levels[4] (16 March to 21 June 2020, inclusive). We also quantified how excess mortality by cause varied by area deprivation (quintiles of the 2020 Scottish Index of Multiple Deprivation, or SIMD).

Deaths with an underlying cause of COVID-19 contributed most (82%) to the 32% excess in mortality rates in the 14 week period, compared to the average for the time of year (Figure xx). Other underlying causes contributing to the excess were dementia and Alzheimer’s (8% contribution), external and ill-defined causes (8%), circulatory causes (3%), other causes (3%), cancer (2%) and diabetes (2%). Deaths from respiratory causes were lower than the average for the time of year (-7% contribution), potentially due to COVID-19 being the underlying cause of death for people who may otherwise have died from respiratory conditions.

Pre-existing absolute and relative inequalities in mortality from dementia and Alzheimer’s, external and ill-defined causes, and circulatory causes widened further during the 14 week period. Inequalities in external and ill-defined causes widened the most. External and ill-defined causes of death were grouped for our analysis because some external causes (including some drug-related deaths, alcohol-related deaths, and suicides) are coded as ill-defined in these provisional data, pending further investigation.

The findings provide some support for various hypotheses about non-COVID-19 excess mortality, including undiagnosed COVID-19, reduced use of health services by those that need them, and unintended consequences of measures taken to control the spread of the virus. To inform future measures that may be taken to control the spread of viruses such as COVID-19 it will be important to understand these wider implications of non-clinical responses to the pandemic.

[1] Excess deaths defined as those in excess of the average for the time of year. Our analysis used the pooled average for the same weeks of 2015-19 as the average for the time of year.

[2] Deaths involving coronavirus (COVID-19) in Scotland. Week 23 (1 to 7 June 2020). Edinburgh, National Records of Scotland, 10 June 2020.

[3] Underlying causes: COVID-19 (ICD10 code U07), cancer (C00-C97), respiratory (J00-J99), circulatory (I00-I99), dementia and Alzheimer’s (F01, F03, G30), diabetes mellitus (E10-E14), external and ill-defined (V, W, X, Y, R), other.

[4] Deaths involving coronavirus (COVID-19) in Scotland. Week 26 (22 to 28 June 2020). Edinburgh, National Records of Scotland, 1 July 2020.