Rates of death in the HC, HC+AZ, and no HC groups were 27.8%, 22.1%, 11.4%, respectively.
Rates of ventilation in the HC, HC+AZ, and no HC groups were 13.3%, 6.9%, 14.1%, respectively.
Compared to the no HC group, the risk of death from any cause was higher in the HC group (adjusted hazard ratio, 2.61; 95% CI, 1.10 to 6.17; P=0.03) but not in the HC+AZ group (adjusted hazard ratio, 1.14; 95% CI, 0.56 to 2.32; P=0.72).
The risk of ventilation was similar in the HC group (adjusted hazard ratio, 1.43; 95% CI, 0.53 to 3.79; P=0.48) and in the HC+AZ group (adjusted hazard ratio, 0.43; 95% CI, 0.16 to 1.12; P=0.09), compared to the no HC group.
CONCLUSIONS:
In this study, we found no evidence that use of hydroxychloroquine, either with or without azithromycin, reduced the risk of mechanical ventilation in patients hospitalized with Covid-19.
An association of increased overall mortality was identified in patients treated with hydroxychloroquine alone.
These findings highlight the importance of awaiting the results of ongoing prospective, randomized, controlled studies before widespread adoption of these drugs.
.....
However, given its increasingly widespread use, not only as therapy but also as prophylaxis for Covid-19, there is a great and immediate need to obtain insights into the clinical outcomes among patients currently treated with hydroxychloroquine, particularly because of the non-negligible toxicities associated with its use.
A study, not peer-reviewed:
Outcomes of hydroxychloroquine usage in United States veterans hospitalized with Covid-19
HC= hydroxychloroquine,
HC+AZ = hydroxychloroquine and azithromycin
no HC = no hydroxychloroquine
The same result bigger n: https://blogs.sciencemag.org/pipeline/archives/2020/05/22/hydroxychloroquine-enough-already
The paper was retracted.