The average figure of 10.1 years of life lost does not account for the
fact that those who have died with COVID-19 have often been in poor
health, conditional on their age. In their detailed study of 23,804
hospital deaths in England from COVID-19 from 1st March 2020 to 11th May
2020, Valabhji et al (2020) (22) found that various life-shortening risk
factors were significantly more prevalent in those patients who died of
COVID-19 than in the general population. This included diabetes (33% vs
5%), and previous hospital admission for significant cardiovascular
comorbidities including coronary heart disease (31% vs 3.5%),
cerebrovascular disease (19.8% vs 1.5%) and heart failure (17.7% vs
1%).
Other comorbidities such as dementia in its various forms, chronic
obstructive pulmonary disease (COPD), vitamin D deficiency, and
hyperlipidaemia were not collected and compared, but it is plausible
that these would also show similar levels of differences. Each of these
comorbidities has been shown to significantly increases the risk of
early death. The National Diabetes
Audit in their mortality study
(23) found that the presence of diabetes increases a person standard
mortality risk by a factor of 1.6.
It is, therefore, plausible that those patients who died of COVID-19
were, on average, already in relatively poor health for their age and
this poor health would give them a life expectancy, on average,
significantly below that of the age-equivalent general population.
These comorbidities and conditions also reduce the person’s quality of
life, as well as its quantity (24). The impact of poor health through
long-term conditions and comorbidities are usually incorporated into
modelling through a quality of life utility factor which ranges from 1
(healthy) to 0 (death); this is used to adjust the total life years.
Beaudet et al (2014) (25), found that the basic type 2 diabetes without
complication had a factor of 0.79 and then other comorbidities would
reduce this further including myocardial infarction −0.06, ischemic
heart disease −0.09, heart failure −0.11, and stroke -0.16. An average
poor health utility factor of 0.8 could be applied to the population of
those who have died with COVID-19.
A substantial downwards adjustment to the 10 years estimate of the
residual life expectancy based on the general population would seem
appropriate for the group who have died with COVID-19. How great an
adjustment is hard to be precise about, but It might plausibly be by one
half. In the calculations below we apply either no adjustments for
co-morbidities or an adjustment of one-half, using lost average
quality-adjusted life years per COVID-19 death of 10 or 5 years.