The study is only observational, and will not end the debate surrounding the treatment " miracle ", and very controversial and promoted by the professor in marseille Didier Raoult, since it bears on patients, with severe forms of Covid-19. It is, however, to this day, the most serious ever carried out to assess, among other things, the effectiveness of hydroxychloroquine, associated or not with a macrolide (antibiotic, editor's NOTE), in the treatment of the disease.
In this study, published Friday by The Lancet, researchers from the hospitals of Zurich and Boston have analyzed the treatment responses of 96 032 patients hospitalized between December 20, 2019 and April 14, 2020, all positive Sars-CoV-2, in 671 hospitals spread over 6 continents. At the end of the study, all patients were either deceased or out of the hospital.
We have been unable to confirm a benefit of hydroxychloroquine or chloroquine
And the results speak for themselves. "We have been unable to confirm a benefit of hydroxychloroquine or chloroquine (...) on the prognosis of patients Covid-19-hospitalized patients ", write the authors. On the other hand, " each of these protocols, when it has been used for the treatment of Covid-19, has been linked to reduced survival in hospital and an increase in the occurrence of ventricular arrhythmias ". In the treated groups, the mortality ranges between 16.4 per cent and 23.8 per cent, whereas it reached only 9.3 % in the control group. The cocktail hydroxychloroquine-macrolide is the most problematic, as resulting in the death of 23.8% of the patients, or one in four. For the patients subjected to this treatment, the study concluded, the risk of death is, therefore, multiplied by five.
serious side effects
The authors explain this excess mortality by the appearance of serious side effects, primarily cardiovascular, in patients submitted to treatment, the most deleterious being the association hydroxychloroquine-azithromycin. And it is not surprising : hydroxychloroquine and azithromycin are known to prolong the QT interval, the a data measured by the electrocardiogram. The prolongation of this interval may be at the origin of heart rhythm disturbances that can, in a small number of patients, cause of syncope, or even sudden deaths.
The doses administered in the treatment of Covid-19, close to the threshold of toxicity, and that more is on patients at a higher risk of complication, as with many co-morbidities, exposed to "an increased risk of ventricular arrhythmia," stressed the authors. Which conclude : "We found no evidence of the benefit of hydroxychloroquine or chloroquine, associated or not with a macrolide. Previous evidence came from a small number of studies, anecdotal evidence, or small randomized trials inconclusive. (...) Although observational studies cannot fully account for unmeasured confounding factors, our findings suggest not only the absence of therapeutic benefit from these treatments, but also their potential hazard for hospitalized patients with the Covid-19. "
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