Ethics and regulation:
This is a retrospective, observational cohort study. All patients
diagnosed with COVID-19 by PCR identification of SARS-CoV-2 were invited
to attend either the outpatient clinic or our hospital for evaluation
and treatment. Data which emerged from epidemiological interviews and
clinical and biological assessments were recorded in the hospital
information system (HIS). For the purposes of this study, data from
patients hospitalised between 3 March 2020 and 13 March 2021 were
extracted from the HIS. To comply with the European General Data
Protection Regulation, all patients were informed that their personal
and medical data might be used for research purposes unless they
refused. The investigators’ declaration to comply with reference method
MR 004 was filed prior to the onset of this study and was the subject of
a declaration in the GDPR/APHM Register No.2020-152.
Data collection: We first selected all patients
hospitalised in our Institute within the one-year study period. To avoid
bias or the use of inappropriate data, we excluded those who were
immunocompromised (3), those mis-diagnosed as having COVID-19 (3), those
treated with ivermectin alone (48), one minor patient (under the age of
18), 273 patients who were hospitalised for less than three days, 95
patients for whom treatment started more than four days after admission,
and 17 patients for whom the timescale between admission and the first
PCR test was more than 15 days (Figure 1 ). We then retained
those for whom a positive PCR was obtained between D0-1 and D0+1. For
patients who were treated with HCQ and/or AZT, “D0” was defined as the
date treatment started (first treatment received). For patients who were
not treated with HCQ or AZT, “D0” was defined as the date of admission
to the IHU. Finally, we included those who had a second (positive or
negative) PCR test between D0+1 and D0+10. All qPCR tests were performed
in the same laboratory. When the CT of the qPCR was over 35 cycles, it
was considered to be negative timescale between the onset (18).
Explicative variables such as, age, initial viral load, date of onset of
symptoms, treatment, and death were extracted from the HIS in compliance
with the provisions of the GDPR. We identified four treatment groups:
those who were treated with the HCQ regimen; those that did not receive
HCQ; those treated with a combination of HCQ and AZ; and those treated
only with AZ. We conducted an initial analysis of treatment with HCQ
(with or without AZ) compared to treatment without HCQ (AZ alone or
nothing), and a second analysis comparing patients treated with HCQ and
AZ to those receiving AZ alone (excluding those receiving HCQ alone).