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.