Among individuals who die of COVID-19, is the percentage who had diabetes actually higher than in those dying of other viral infections?

Background: Early in the COVID-19 pandemic, mainstream news outlets sensationalized that 30-40% of all coronavirus deaths in the United States occurred among individuals with diabetes. It was unclear why this would be news-worthy because 30-40% is approximately the prevalence of diabetes in older adult, the age group most at risk for mortality from COVID-19. Thus, we sought to quantify the proportion of decedents from COVID-19 who had diabetes. To understand the proportion in context, we also calculated the proportion of decedents from influenza who had diabetes. Methods: For assessing COVID-19 decedents who had diabetes, we used the National COVID Cohort Collaborative (N3C) data enclave, a nationally-representative, harmonized, and de-identified electronic health record database. For assessing influenza decedents who had diabetes, we used Medicare data. We restricted the N3C sample to > 65 years to align with Medicare eligibility. Results: Among seniors with inpatient mortality due to COVID-19, 46.6% (95% CI: 46.1-47.0) had diabetes. Among seniors with inpatient mortality from influenza, the crude percent with diabetes was 61.2%. When age-standardized to match the N3C COVID-19 data, the percentage of influenza decedents with diabetes was 63.1% (95% CI: 59.1-67.1). Conclusions: Among seniors with inpatient mortality from respiratory viruses, a very large proportion had diabetes before infection: 63% of influenza decedents and 47% of COVID-19 decedents. Thus, a high proportion of decedents having diabetes is not new or unique to COVID-19. These findings highlight the value of using available data to contextualize health communication to the public.