Nearly 30% of excess deaths in New York state not related to coronavirus pandemic, says study
Researchers have identified a substantial proportion of excess deaths during the coronavirus pandemic that are not attributed to COVID-19.
They may represent an excess of deaths due to other causes, show a new study, which analyzed data for New York State in the US and three Northern European countries (England and Wales, Scotland and the Netherlands).
According to the analysis, there has been a substantial increase — ranging from 26 to 62% — in observed deaths, compared with expected death at a population level.
The increase in deaths is not wholly explained by deaths attributed to COVID-19. An estimated 51 to 70% of the excess in deaths can be explained by official COVID-19 reports, says the research team.
The data from New York state support these findings, with an even more striking picture in New York City, they emphasize.
The two most likely explanations for the discrepancy between the overall excess of deaths and the extra deaths explained by COVID-19 are either that there are additional deaths caused (or contributed to) by COVID-19, but not recognized as such, or that there is an increase in deaths from non-COVID-19 causes, potentially resulting from reduced routine diagnosis and treatment of other condition, say experts.
"We believe that both are likely," says the team. They explain, "In many reports of mortality attributed to COVID-19, the focus has been on deaths occurring in the hospital. Similarly, in some countries due to limited testing for SARS-CoV-2 (the virus that causes COVID-19), deaths among elderly people in care homes and other places potentially caused (or contributed to) by COVID-19 are not attributed to that condition."
"There are anecdotal reports of people with COVID-19-like symptoms frightened to attend hospital or choosing to remain at home because of fear of dying in isolation from their family in the hospital."
The team includes researchers from the University of Glasgow, UK, Brigham and Women's Hospital, US, Rigshospitalet Copenhagen University Hospital, Denmark, University of Groningen, University Medical Center Groningen, Netherlands, and Associazione Nazionale Medici Cardiologi Ospedalieri Research Center, Italy.
"There was an increase in observed, compared with expected, mortality in Scotland (+27%), England and Wales (+35%), the Netherlands (+60%), and New York state (+26%). Of these deaths, 57% in Scotland, 57% in England and Wales, 51% in the Netherlands, and 70% in New York state were attributed to COVID-19, leaving a number of excess deaths not attributed to COVID-19," say researchers in their findings, a pre-print version of which has been published.
The results
For the study, the research team extracted reports of the numbers of deaths related to COVID-19 published by national agencies and death registration authorities that had been publicly reported upto April 16, 2020.
Data on the number of deaths due to COVID-19 and the total number of deaths registered in the population over the same period were collected. Historical numbers of deaths or the average number of deaths from 2015-2019 for the same week were extracted from available records.
"The number of excess deaths was defined as the difference between the observed number of deaths and the number of deaths expected according to the observed number from 2015-2019. The number of deaths related to COVID-19 was then deducted from the excess deaths to calculate the number of non-COVID-19 defined excess deaths," explains the team.
The analysis for New York State shows that the number of deaths increased from an expected 34,835 (based on the prior average from 2015-2018) to 43,962 (26% increase) between January 26 to April 11 this year. Of the 9,127 excess deaths, 6,402 (70%) were related to COVID-19.
"As a result, the overall death rate for the 11 weeks increased from an expected 1,783 per million to 2,250 per million of population. The rate of COVID-19-related deaths was 328 per million, and the rate of excess deaths not attributed to COVID-19 was 139 per million of population," says the study.
The equivalent figures for New York City were a 62% increase — from 12,088 expected deaths (based on 2015-2017 average) to 19,569 deaths over the period of January 26 to April 11.
Of the 7,481 excess deaths, 4,483 (60%) were related to the new coronavirus. The overall death rate rose from an expected 1,439 per million to 2,329 per million of the population.
The rate of COVID-19-related deaths was 534 per million, and the rate of excess deaths not attributed to COVID-19 was 357 per million of population, shows analysis. “After averaging the rates into a 7-day period, similar rates of deaths and excess COVID-19 and non-COVID-19 deaths were observed," says the team.
Similarly, in England and Wales, there were 7,093 excess deaths between March 21 to April 3, a 35% increase from the prior five-year average. Of these excess deaths, 4014 (57%) were COVID-19-related.
"As a result, the death rate rose from an expected of 346 per million to 466 per million of population. The rate of COVID-19-related deaths was 68 per million, and the rate of excess deaths not attributed to COVID-19 was 52 per million of population," the findings state.
In Scotland, there were 604 excess deaths between March 23 to April 5, compared to the same period in 2015-2019 (an increase of 27%). Of these excess deaths, 344 (57%) were recorded as related to COVID-19.
Researchers found that the death rate for the two weeks examined went up from 408 per million (based on the 5-year average) to 519 per million of the population. The rate of excess deaths attributed to COVID-19 was 63 per million, and the rate of excess deaths not attributed to COVID-19 was 48 per million.
The assessment for the Netherlands shows that the number of deaths increased from an expected 5,953 (based on the prior 5-year average) to 9,523 (60% increase) between March 23 Apri 5 this year. Of the 3,570 excess deaths, 1,814 (51%) were related to COVID-19.
The overall death rate increased from an expected 346 per million to 553 per million of the population. The rate of COVID-19-related deaths was 105 per million, and the rate of excess deaths not attributed to COVID-19 was 102 per million of the population.
Researchers say it will take time to fully explain the trends described in the study, particularly to quantify the exact causes of the excess of non-COVID-19 deaths. "Even then, it may be difficult to accurately determine whether COVID-19 caused or contributed to death," they add.
What are the implications of these findings? According to experts, the study suggests that people should be reminded that it is still appropriate to seek medical attention for other serious life-threatening illnesses during this period and service delivery must be adapted to provide this.
"We believe that the public health message to 'stay at home' needs to be more nuanced, with an equally clear message to patients with symptoms suggestive of an acute coronary syndrome, stroke, and worsening of chronic heart failure to still seek urgent medical attention. This may need reconfiguration of admission procedures to avoid mixing of suspected Covid-19 patients and other emergencies," say researchers.
The findings reinforce the "necessity of efforts being made to adapt ambulatory secondary care and primary care services." This will enable the continued delivery of essential treatment to high-risk patients with chronic diseases and the triage of newly presenting individuals with potentially life-threatening conditions, says the team.