The hypothesis that immunosuppression may protect you from severe COVID-19 is gaining traction. New data released on the 4th April 2020 from the UK’s Intensive Care National Audit & Research Centre suggests it may. When comparing 2249 patients admitted to ITU in the UK with severe COVID-19 the proportion of immunocompromised patients was 3.7x lower than the proportion of immunocompromised patients admitted to ITU with viral pneumonia (the comparator) between 2017 and 2019 (2.3% vs. 8.5%). This was a highly significant difference (p<0.00001).
This clearly justifies the current research strategy being tested across the planet to see if immunosuppressive therapies may improve disease outcome in patients with COVID-19.
Does this mean we can now assume that immunosuppression protects against severe COVID-19 and COVID-19-related ARDS (adult respiratory distress syndrome)? Not yet. The UK’s ITU cohort of severe COVID-19 is biased in that those patients who are deemed too frail and/or disabled may never get to ITU, which may include a disproportionate number of immunosuppressed patients. Whereas this specific bias is unlikely to apply to ITU admissions between 2017 and 2019 (viral pneumonia cohort) when there was no such pressure on resources.
Despite this caveat, this is an important tidbit of information that will allow pwMS on immunosuppression to sleep a bit easier. I sincerely hope the wider MS community will reconsider their advice about not giving MS DMTs that are if anything mildly immunosuppressive to patients with active MS. By not treating our patients we may unintentionally be increasing their chances of developing severe COVID-19. Could our guidelines be another example of the law of unintended consequences? Let’s hope the real-world data that is being collected at present will answer this question.