Retrospective 50 COVID-19 patients that take chronic HCQ, compared to a matched sample of patients not taking chronic HCQ, showing lower mortality and ICU admission, and shorter hospitalization for HCQ patients, but not statistically significant due to the small number of events.
The actual benefit for HCQ could be much larger. The study does not address the risk of being sick enough to visit the hospital. HCQ users are likely systemic autoimmune disease patients and authors do not adjust for the very different baseline risk for these patients. Other research shows that the risk of COVID-19 for systemic autoimmune disease patients is much higher overall, Ferri et al. show OR 4.42,
p<0.001 [1].
Rangel et al., 1/10/2021, retrospective, USA, North America, peer-reviewed, 5 authors.
risk of death, 25.1% lower, RR 0.75, p = 0.77, treatment 4 of 50 (8.0%), control 11 of 103 (10.7%), from all patients.
risk of hospitalization, 22.2% lower, RR 0.78, p = 0.29, treatment 17 of 50 (34.0%), control 45 of 103 (43.7%).
hospitalization time, 41.2% lower, relative time 0.59, p = 0.12, treatment 21, control 54.