BMI- and age-related associations with mortality from COVID-19.

We congratulate the COVIDSurg and GlobalSurg Collaboratives for their recent article [1], which addresses a fundamental surgical concern during the COVID‐19 pandemic. Although the authors rightfully decided on a host of probable confounding factors to include in their regression modelling a priori, we believe an important variable was omitted from the analysis that requires adjustment, namely BMI. Since higher BMIs are associated with a greater risk of contracting COVID‐19 [2] and COVID‐19‐related mortality [3], this variable could potentially complicate the results of this investigation and conclusions based on its findings. Thus, the regression models should account for BMI in order to better ascertain the correlation between timing of surgery after COVID‐19 and mortality.

As paediatric anaesthetists, we are also concerned as to whether the results of this study can be generalised to our paediatric practice, because COVID‐19‐related death occurs at a far lower rate in those aged 0–17 y relative to those who are older [4]. We believe that performing a sensitivity analysis that includes only patients aged < 18 y would be beneficial to paediatric anaesthetists and surgeons in our continual pursuit of optimal patient care and safety.