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. 2020 Dec:101:283-289.
doi: 10.1016/j.ijid.2020.09.1460. Epub 2020 Sep 29.

Early hydroxychloroquine but not chloroquine use reduces ICU admission in COVID-19 patients

A J J Lammers  1 , R M Brohet  2 , R E P Theunissen  3 , C Koster  3 , R Rood  4 , D W M Verhagen  5 , K Brinkman  6 , R J Hassing  7 , A Dofferhoff  8 , R El Moussaoui  9 , G Hermanides  10 , J Ellerbroek  11 , N Bokhizzou  12 , H Visser  13 , M van den Berge  14 , H Bax  15 , D F Postma  16 , P H P Groeneveld  3
Affiliations

Early hydroxychloroquine but not chloroquine use reduces ICU admission in COVID-19 patients

A J J Lammers et al. Int J Infect Dis. 2020 Dec.

Abstract

Background: The global push for the use of hydroxychloroquine (HCQ) and chloroquine (CQ) against COVID-19 has resulted in an ongoing discussion about the effectivity and toxicity of these drugs. Recent studies report no effect of (H)CQ on 28-day mortality. We investigated the effect of HCQ and CQ in hospitalized patients on the non-ICU COVID-ward.

Methods: A nationwide, observational cohort study was performed in The Netherlands. Hospitals were given the opportunity to decide independently on the use of three different COVID-19 treatment strategies: HCQ, CQ, or no treatment. We compared the outcomes between these groups. The primary outcomes were 1) death on the COVID-19 ward, and 2) transfer to the intensive care unit (ICU).

Results: The analysis included 1064 patients from 14 hospitals: 566 patients received treatment with either HCQ (n = 189) or CQ (n = 377), and 498 patients received no treatment. In a multivariate propensity-matched weighted competing regression analysis, there was no significant effect of (H)CQ on mortality on the COVID ward. However, HCQ was associated with a significantly decreased risk of transfer to the ICU (hazard ratio (HR) = 0.47, 95% CI = 0.27-0.82, p = 0.008) when compared with controls. This effect was not found in the CQ group (HR = 0.80, 95% CI = 0.55-1.15, p = 0.207), and remained significant after competing risk analysis.

Conclusion: The results of this observational study demonstrate a lack of effect of (H)CQ on non-ICU mortality. However, we show that the use of HCQ - but not CQ - is associated with a 53% reduction in risk of transfer of COVID-19 patients from the regular ward to the ICU. Recent prospective studies have reported on 28-day, all-cause mortality only; therefore, additional prospective data on the early effects of HCQ in preventing transfer to the ICU are still needed.

Keywords: Azithromycin; COVID-19; Chloroquine; Clinical course; Hydroxychloroquine.

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Figures

Figure 1
Figure 1
Number of included COVID-19 patients. HCQ = hydroxychloroquine, CQ = chloroquine.
Figure 2
Figure 2
Cumulative incidence functions (CIF) by type of medication. A. Cumulative risk of death. B. Cumulative risk of transfer to ICU.
See this image and copyright information in PMC

Comment in

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