In people with type 2 diabetes most risk factors for covid-19 mortality are shared with pneumonia, however ethnicity related risk is very different

ABSTRACT

Aims: Previous UK population research identified multiple risk factors for increased covid-19 mortality in people with type 2 diabetes but it is unclear if these are general to respiratory infections or specific to covid-19. We aimed to compare risk factors associated with death from covid-19 (pre-vaccination roll-out) and pneumonia. Methods: In UK routine primary care data (CPRD), we followed adults with type 2 diabetes from 01/09/2019-31/ 01/2020 (pneumonia mortality cohort n = 609,079) and 01/02/2020-31/ 10/2020 (covid-19 mortality cohort n = 587,933). Multivariable Cox proportional hazards models were used to identify risk factors in each cohort. Results: We observed 2,690 deaths (0.5%) due to covid- 19, and 1,612 deaths due to pneumonia (0.3%). For covid- 19 mortality, we replicated previously reported risk factor associations for male sex, older age, higher deprivation, higher BMI, renal impairment, previous stroke and cardiovascular disease. These features were also associated with higher pneumonia mortality. A differential effect was observed for ethnicity compared to people of white ethnicity, black and south Asian groups had higher covid-19 mortality (adjusted hazard ratio [aHR] 2.07 [95%CI 1.81-2.38], p < 0.001, and 1.50 [1.33-1.70], p < 0.001 respectively), but lower pneumonia mortality (aHR 0.43 [95%CI 0.31-0.60], p < 0.001, and 0.54 [0.43-0.68], p < 0.001 respectively). Higher HbA1c was a stronger risk factor for covid-19 mortality than pneumonia mortality (aHRs [95%CI] HbA1c >86 vs 48-53 mmol 1.30 [1.09-1.54], p = 0.004 for covid- 19, 1.10 [0.86-1.42], p = 0.442 for pneumonia). Conclusions: In type 2 diabetes, clinical risk factors for covid-19 and pneumonia mortality are largely similar, but non-white ethnicities have disproportionately higher risk of covid-19 mortality compared to lower risk of pneumonia mortality, which needs further exploration.