Misleading: Comorbidities are medical conditions that weaken the patient and may lower their chance of surviving COVID-19 but are not the underlying cause of death. The claim fails to consider that doctors assess the entire chain of clinical events leading to the death of a patient in order to determine the cause. For deaths to be attributed to COVID-19, the clinical events assessed must be compatible with known COVID-19 symptoms.
FULL CLAIM: only 6% of all the 153,504 deaths recorded actually died from Covid, the rest had other serious illnesses
The claim that only 6% of COVID-19 deaths officially recorded in the U.S. were actually due to the disease started circulating on social media in late August 2020, and was shared on Twitter by U.S. President Donald Trump. The author of this claim uses flawed reasoning by confusing a cause of death with a comorbidity in its challenge against the accuracy of data from the U.S. Centers for Disease Control and Prevention (CDC) that list the comorbidities of patients who died from COVID-19.
On 26 August 2020, the CDC reported that 6% of the deaths from COVID-19 were not associated with comorbidities. Based on this report, the claim suggests that only those 6% actually died from the disease and that the other 94% died from their comorbidities. An alternate version of the claim states that only 6% of the deaths currently attributed to COVID-19 are due to the disease alone, and that the comorbidities reported for the other patients with COVID-19 are additional or alternate causes of death. Both claims misrepresent comorbidity as a cause of death, instead of a contributing factor to the patient’s demise.
In its guidelines, the CDC explains that cause of death is “the disease or injury which initiated the train of morbid events leading directly to death”. In the case of COVID-19, comorbidities, which are reported elsewhere on the death certificate, are medical conditions that decrease the overall health of the patient and weaken their ability to survive COVID-19. Some of the comorbidities can be pre-existing, such as diabetes, while others may be a consequence of the infection by SARS-CoV-2, although not directly involved in the sequence of clinical events leading to death. Hence, the major difference between a cause of death and a comorbidity is that comorbidities do not trigger the series of events leading to the patient’s death. In many cases, if the disease or injury had been avoided, those patients with comorbidities would not have died at that time. For example, as seen in Table 3 of this CDC report, 4.6% of patients reported as dying from COVID-19 also had malignant neoplasms (cancer), which may have contributed to their inability to survive COVID-19.
On 16 April 2020, the World Health Organization stated that comorbidities can increase a patient’s risk of dying from COVID-19 in its international guidelines for certification and classification of COVID-19 as the cause of death:
“There is increasing evidence that people with existing chronic conditions or compromised immune systems due to disability are at higher risk of death due to COVID-19. Chronic conditions may be non-communicable diseases such as coronary artery disease, chronic obstructive pulmonary disease (COPD), and diabetes or disabilities. If the decedent had existing chronic conditions, such as these, they should be reported in Part 2 of the medical certificate of cause of death.”
In addition, the claim fails to consider that a patient’s death certificate reports the whole chain of medical events leading to their death. For instance, a typical death certificate of someone who died from COVID-19 reports that the death occurred following an acute respiratory distress syndrome due to pneumonia triggered by COVID-19. Deaths are not classified as “COVID-19 deaths” merely because the disease is confirmed or suspected. Instead, the clinical evolution of the patient has to be compatible with the course of the disease to be classified as a death from COVID-19. World Health Organization (WHO) guidelines also state that “Persons with COVID-19 may die of other diseases or accidents, such cases are not deaths due to COVID-19 and should not be certified as such.” For instance, a patient whose death certificate lists cancer as a cause of death would have presented clinical signs and symptoms consistent with cancer, not with COVID-19. Such a patient would not be reported as a COVID-19 death.
Furthermore, the claim incorrectly concludes that only the 6% of patients who did not have comorbidities actually died from the disease. By doing so, the claim falsely assumes that if a comorbidity was present in patients who died from COVID-19, then the comorbidity was the cause of death, not COVID-19. There is no reason to assume that a patient suffering from Alzheimer’s disease and COVID-19, for example, would always die from the former and never from the latter, nor that all deceased patients who were both obese and suffering from COVID-19 died from obesity and not from COVID-19.
The CDC also compares the number of deaths that occurred in 2020 with the average number of deaths from the previous year to quantify “excess deaths”. As shown in the figure below, there was a slight increase in the number of excess deaths in early January 2018, corresponding to a severe influenza season (Figure 1). A significant number of excess of deaths also occurred during the second and third quarter of 2020. For April 2020 and May 2020 alone, the number of deaths that exceeded the average number of deaths from previous years was more than 110,000. The New York Times has reported that at least 200,000 excess deaths have occurred in the U.S. between March and August 2020. This number is far larger than the 9,000 deaths of patients who did not present comorbidities. The claim’s hypothesis is thus incompatible with the higher mortality observed in the U.S. this year.
In summary, the claim confuses the actual cause of death, which is the event that triggers a chain of medical events leading to death, with comorbidity, which is a medical condition that may weaken the overall health of a patient and thus contribute to the fatal outcome of a disease. As stated by the WHO, patients in poor health are more likely to die from COVID-19 relative to patients who are generally in good health. However, the presence of additional medical conditions does not mean that these patients cannot die from COVID-19. The claim’s logic is flawed, as it assumes that the 94% of deceased patients who had COVID-19 and another medical condition did not die from COVID-19 and always died from the other conditions. The deaths recorded in 2020 show a significant number of excess deaths compared to previous years, however there is no data or mechanism to explain why there would be an increase in the number of deaths from previously-known medical conditions, such as Alzheimer’s, diabetes or obesity. The spike in excess deaths seen this year can only be attributed to the COVID-19 pandemic caused by the novel coronavirus SARS-CoV-2.