- Hydroxychloroquine, azithromycin, or the combination was not associated with significantly lower in-hospital mortality in this US cohort study of hospitalized patients with COVID-19.
Why this matters
- Editorials have already called for caution because of concerns about prolonged QTc and preliminary findings of an earlier phase 3 study from Brazil suggesting safety and mortality concerns with higher doses of chloroquine diphosphate.
- 1438 patients included; most were male, age >45 years.
- Hydroxychloroquine+azithromycin: 51.1% (735).
- Hydroxychloroquine alone: 18.8% (271).
- Azithromycin alone: 14.7% (211).
- Neither: 15.4% (221).
- At 21 days, estimated mortality averaged across all observed patient covariate patterns (95% CIs):
- Hydroxychloroquine+azithromycin: 22.5% (19.7%-25.1%).
- Hydroxychloroquine alone: 18.9% (14.3%-23.2%).
- Azithromycin alone: 10.9% (5.8%-15.6%).
- Neither: 17.8% (11.1%-23.9%).
- Adjusted HRs (95% CIs) for mortality were not significant vs use of neither drug:
- Combination: 1.35 (0.76-2.40).
- Hydroxychloroquine alone: 1.08 (0.63-1.85).
- Azithromycin alone: 0.56 (0.26-1.21).
- Mortality did not differ significantly between hydroxychloroquine only vs azithromycin only (adjusted HR, 1.92; 95% CI, 0.99-3.74).
- Compared with patients receiving neither drug, cardiac arrest was more likely with the combination (aOR, 2.13; 95% CI, 1.12-4.05), but not with hydroxychloroquine alone (1.91; 0.96-3.81) or azithromycin alone (0.64; 0.27-1.56).
- Retrospective, multicenter cohort study of hydroxychloroquine and azithromycin prescribing patterns in patients hospitalized with COVID-19 in New York State.
- Funding: None disclosed.
- Retrospective, observational.
- Uncaptured readmissions.
- Residual confounding likely.