et al., Annals of the Rheumatic Diseases, doi:10.1136/annrheumdis-2020-217717 (Letter)
Survey of 165 SLE patients, 127 on HCQ. 8 patients with suspected COVID-19 and 4 confirmed cases. No mortality, one ICU case. 7 patients had no symptoms despite contact with a COVID-19 patient.
No adjustment for concomitant medications or severity of SLE. Confounding by indication.
Cassione et al., 5/12/2020, retrospective, Italy, Europe, preprint, survey, median age 52.5, 6 authors.
risk of COVID-19 case, 49.6% higher, RR 1.50, p = 0.59, treatment 10 of 127 (7.9%), control 2 of 38 (5.3%).