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Research Article| Volume 118, P224-229, May 2022

Assessment of Recovery Time, Worsening, and Death among Inpatients and Outpatients with COVID-19, Treated with Hydroxychloroquine or Chloroquine plus Azithromycin Combination in Burkina Faso

Open AccessPublished:February 25, 2022DOI:https://doi.org/10.1016/j.ijid.2022.02.034

      Highlights

      • Hydroxychloroquine + azithromycin (HCQ + AZ) did not reduce recovery time in COVID-19
      • HCQ + AZ had no effect on the risk of worsening or transfer to the intensive care unit
      • The use of HCQ + AZ appeared to be associated with lower mortality rates

      Abstract

      Objectives

      Our study aimed to assess the statistical relationship between the use of chloroquine phosphate or hydroxychloroquine plus azithromycin (CQ/HCQ + AZ) and virological recovery, disease worsening, and death among out- and inpatients with COVID-19 in Burkina Faso.

      Methods and Designs

      This was a retrospective observational study that compared outcomes in terms of time to recovery, worsening, and death in patients who received CQ/HCQ + AZ and those who did not using a multivariable Cox or Poisson model before and after propensity matching.

      Results

      Of the 863 patients included in the study, about 50% (432/863) were home-based follow-up patients and 50% were inpatients. Of these, 83.3% (746/863) received at least 1 dose of CQ/HCQ + AZ and 13.7% (118/863) did not. There were no significant differences in associated time to recovery for patients receiving any CQ/HCQ + AZ (adjusted HR 1.44; 95% CI 0.76–2.71). Similarly, there was no significant association between CQ/HCQ + AZ use and worsening (adjusted IRR 0.80; 95% CI 0.50–1.50). However, compared with the untreated group, the treated group had a lower risk of death (adjusted HR 0.20; 95% CI 0.10–0.44).

      Conclusions

      The study provided valuable additional information on the use of CQ/HCQ in patients with COVID-19 and did not show any harmful outcomes of CQ/HCQ + AZ treatment.

      Keywords

      Background

      The COVID-19 is a worldwide, ongoing pandemic due to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The first case was identified in the Chinese city of Wuhan in December 2019 (
      • Zhu N
      • Zhang D
      • Wang W
      • Li X
      • Yang B
      • Song J
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      A Novel Coronavirus from Patients with Pneumonia in China, 2019.
      ). On March 11, 2020, the COVID-19 outbreak was declared as pandemic by the WHO (

      World Health Organization. WHO Director-General's opening remarks at the media briefing on COVID-19-11 March 2020. 2020.

      ). In Burkina Faso, the first suspected case of COVID-19 was reported on February 5, 2020 (
      • Tarnagda Z
      • Cissé A
      • Ilboudo AK
      • Lingani M
      • Kondombo JC
      • Bationo Cedric
      • Stéphane Kyere AE
      • et al.
      COVID-19 Outbreak in Burkina Faso: Epidemiological Surveillance among High Risk Population.
      ), while the first confirmed case was notified on March 9, 2020 (
      WHO
      Coronavirus disease 2019 (COVID-19) Situation Report—51.
      ;

      Worldometer. Coronavirus Cases. Worldometer 2020. https://www.worldometers.info/coronavirus/coronavirus-cases/#daily-cases (accessed December 31, 2020).

      ). In the research of medicines that could potentially reduce the risk for disease worsening or death, the aminoquinolines chloroquine (CQ) and hydroxychloroquine (HCQ), which are commonly used for the treatment of malaria and rheumatic diseases, were suggested as effective treatments for COVID-19 based on a combination of anti-inflammatory and antiviral effects (
      • Devaux CA
      • Rolain JM
      • Colson P
      • Raoult D.
      New insights on the antiviral effects of chloroquine against coronavirus: what to expect for COVID-19?.
      ;
      • Fox RI.
      Mechanism of action of hy- droxychloroquine as an antirheumatic drug.
      ).
      HCQ was used for the first time in China during an early stage of the pandemic in a small randomized controlled trial of 62 patients to improve pneumonia regression and reduce the recovery time (
      • Zhaowei CJH
      • Zhang Z
      • Jiang S
      • Han S
      • Yan D
      • Zhuang R
      • et al.
      Efficacy of hydroxychloroquine in patients with COVID-19: results ofa randomized clinical trial.
      ). However, the first peer-review published study (open-label, single-arm, nonrandomized study enrolling 26 subjects) reporting the effectiveness of hydroxychloroquine in reducing the viral burden in patients with COVID-19 was conducted in France (
      • Gautret P
      • Lagier JC
      • Parola P
      • Hoang VT
      • Meddeb L
      • Mailhe M
      • et al.
      Hydroxychloroquine and azithromycin as a treatment of COVID-19: results of an open-label non-randomized clinical trial.
      ). Although this empirical scientific evidence has motivated several countries to use this old drug in association with or without azithromycin (AZ) for COVID-19 case management (
      • Dagens A
      • Sigfrid L
      • Cai E
      • Lipworth S
      • Cheung V
      • Harris E
      • et al.
      Scope, quality, and inclusivity of clinical guidelines produced early in the covid-19 pandemic: Rapid review.
      ;
      • Rouamba T
      • Barry H
      • Ouédraogo E
      • Tahita MC
      • Yaméogo NV
      • Poda A
      • et al.
      Safety of chloroquine or hydroxychloroquine plus azithromycin for the treatment of COVID-19 patients in Burkina Faso: An observational prospective cohort study.
      ;

      Wilson KC, Chotirmall SH, Bai C, Rello J. COVID-19: Interim Guidance on Management Pending Empirical Evidence. From an American Thoracic Society-led International Task Force 2020. https://www.thoracic.org/covid/covid-19-guidance.pdf.

      ), it should be highlighted that the efficacy and safety of HCQ in the treatment of patients with SARS-CoV-2 was subject to polemics in the scientific community because of conflicting results. Indeed, while most observational studies reported an improvement of the clinical outcomes with the use of HCQ (
      • Arshad S
      • Kilgore P
      • Chaudhry ZS
      • Jacobsen G
      • Wang DD
      • Huitsing K
      • et al.
      Treatment with hydroxychloroquine, azithromycin, and combination in patients hospitalized with COVID-19.
      ;
      • Ayerbe L
      • Risco-Risco C
      • Ayis S.
      The association of treatment with hydroxychloroquine and hospital mortality in COVID-19 patients.
      ;
      • Bernaola N
      • Mena R
      • Bernaola A
      • Carballo C
      • Lara A
      • Bielza C
      • et al.
      Observational study of the efficiency of treatments in patients hospitalized with Covid-19 in Madrid.
      ;
      • Catteau L
      • Dauby N
      • Montourcy M
      • Bottieau E
      • Hautekiet J
      • Goetghebeur E
      • et al.
      Low-dose hydroxychloroquine therapy and mortality in hospitalised patients with COVID-19: a nationwide observational study of 8075 participants.
      ;
      • Gautret P
      • Lagier JC
      • Parola P
      • Hoang VT
      • Meddeb L
      • Sevestre J
      • et al.
      Clinical and microbiological effect of a combination of hydroxychloroquine and azithromycin in 80 COVID-19 patients with at least a six-day follow up: A pilot observational study.
      ;
      • Lagier JC
      • Million M
      • Gautret P
      • Colson P
      • Cortaredona S
      • Giraud-Gatineau A
      • et al.
      Outcomes of 3,737 COVID-19 patients treated with hydroxychloroquine/azithromycin and other regimens in Marseille, France: A retrospective analysis.
      ;
      • Lammers AJJ
      • Brohet RM
      • Theunissen REP
      • Koster C
      • Rood R
      • Verhagen DWM
      • et al.
      Early hydroxychloroquine but not chloroquine use reduces ICU admission in COVID-19 patients.
      ;
      • Million M
      • Lagier JC
      • Gautret P
      • Colson P
      • Fournier PE
      • Amrane S
      • et al.
      Early treatment of COVID-19 patients with hydroxychloroquine and azithromycin: A retrospective analysis of 1061 cases in Marseille, France.
      ;
      • MILLION M
      • LAGIER J-C
      • TISSOT-DUPONT H
      • RAVAUX I
      • DHIVER C
      • TOMEI C
      • et al.
      Early combination therapy with hydroxychloroquine and azithromycin reduces mortality in 10,429 COVID-19 outpatients.
      ;
      • Yu B
      • Li C
      • Chen P
      • Li J
      • Jiang H
      • Wang DW.
      Beneficial effects exerted by hydroxychloroquine in treating COVID-19 patients via protecting multiple organs.
      ), randomized controlled studies (
      • Pan H
      • Peto R
      • Karim QA
      • Alejandria M
      • Henao-Restrepo AM
      • García CH
      • et al.
      Repurposed antiviral drugs for COVID-19 –interim WHO SOLIDARITY trial results.
      ; The RECOVERY Collaborative
      • Group The RECOVERY Collaborative
      Effect of Hydroxychloroquine in Hospitalized Patients with Covid-19.
      ) were suspended because of apparent ineffectiveness coupled with a tendency for increasing overall mortality.
      As of April 6, 2020, based on limited scientific circumstantial evidence and the observations and experiences of clinicians throughout the world, Burkina Faso has adopted the CQ/HCQ + AZ combination for the systematic treatment of detected COVID-19 cases in the country (

      Ministère de la Santé du Burkina Faso. Arrêté n° 2020-119/MS/CAB du 06 avril 2020 porrtant adoption du protocole national de prise en charge des cas confirmés de COVID-19 intégrant l'hydroxychloroquine et/ou de la chloroquine phosphate 2020.

      ). In such a context, it was important to carry out an observational study to support the implementation of this new treatment policy to assess its effectiveness and safety. Thus, the CHLORAZ research group proposed to conduct an observational study to evaluate the therapeutic protocol proposed by Burkina Faso Ministry of Health (MoH) for the treatment of COVID-19.
      The study aimed to assess the statistical relationship between the use of CQ/HCQ + AZ and virological recovery, disease worsening, and death among patients with COVID-19 in Burkina Faso. The research hypothesis of the study was to test whether the use of CQ/HCQ + AZ would have a beneficial effect on reducing the time to viral negativation, worsening/transfer to an intensive care unit (ICU), or death.

      Methods

      Study design, sites, and participants

      This was a retrospective observational cohort study conducted at the two main cities of Burkina Faso, Ouagadougou and Bobo-Dioulasso, which are the two epicenters of the COVID-19 epidemic in the country, while the other cities of the country reported almost no cases or few cases of COVID-19. The study enrolled patients who had a positive test result for the SARS-CoV-2 regardless of sex and age, admitted to a hospital (university hospitals of Tengandogo and Souro Sanou, Princesse Sara polyclinic, and Pissy medical center), or followed-up at home.

      Data sources and variables assessed

      Patients were included in the study on the basis of the availability of their medical records. These records were reviewed by the study clinicians prior to the data capturing. The data collected included symptoms, medical history, and history of medication use (including HCQ or CQ). At admission, date of diagnosis confirmation by real-time reverse transcriptase polymerase chain reaction (rRT-PCR), CQ/HCQ treatments for the management of the current episode of SARS-CoV-2 infection were collected. Moreover, the duration of the hospital stay (or disease course in terms of worsening or referral to the ICU), date of SARS-CoV-2 negativation confirmed by rRT-PCR, and disease outcomes (in terms of death or recovery) were collected. This study did not consider the viral load because these data were not available for the majority of participants Table 1. summarizes the variables assessed during the study.
      Table 1Summary of parameters used for patient management.
      ParametersUnits of measurement/main modalities
      Type of follow-upHospitalized or followed at home
      Patient demographicsAge (Year), sex (Male, Female)
      Date of hospitalizationDay/Month/Year
      Date of PCR confirmation of diagnosisDay/Month/Year
      Date of SARS-CoV-2 PCR negativityDay/Month/Year
      Medication history on admissionHCQ/CQ, Antibiotics, Antivirals
      Comorbidities and risk factorsTypes/names of comorbidity/risk factors
      Vital signs and general condition and state of consciousness on admissionSaO2, Temperature, Heart rate
      Signs and symptoms on admissionGeneral condition: good, fair, poor; Consciousness: good or impaired; Types/names of signs and symptoms
      HCQ/CQ treatmentsHCQ/CQ prescribed yes or no; Dosage, duration of treatment
      Disease progressionAggravation, referral to intensive care unit; Date of worsening or referral to intensive care unit
      Disease outcomesRecovered or Died; Date of recovery or death

      Hydroxychloroquine or chloroquine or exposure and study end points

      According to the national protocol, hydroxychloroquine was administered at a dose of 200 mg three times a day for 10 days, whereas chloroquine phosphate was administered at 250 mg twice a day for 10 days. Azithromycin was administered at 500 mg on Day 0 and at 250 mg per day from Day 1 to Day 4, for a total of 5 days of treatment. The definition of patients who received CQ/HCQ in our study consisted of patients who received CQ/HCQ at baseline (once the PCR result was positive) or during the follow-up period before the study outcome occurred without counting the duration of the actual treatment of the patients. The study considered three primary outcomes: recovery time, worsening/transfer to the ICU, and death.

      Data management and statistical analysis

      Data were collected by the study physicians on an individual paper case report form from the source documents (patient medical records) before being double-entered into an electronic database developed on OpenClinica database management system. The final database was generated after the resolution of all queries by the field coordinators of the study.
      Categorical variables were presented as frequencies and percentages, and continuous variables were presented as means with standard deviations or median with interquartile ranges (IQRs) and minimum and maximum values, when appropriate. When required, a comparison of continuous data between groups was performed using the unpaired Student's t-test and categorical data was compared using the chi-square test or Fisher exact test. The median time to recovery and the 95% confidence intervals (95% CIs) were calculated using the Kaplan-Meier method. The log-rank statistical test was performed to test the null hypothesis of equal survival curves between the CQ/HCQ group and the non-CQ/HCQ group.
      Unadjusted and adjusted Cox proportional hazards regression models (including demographic variables, Charlson comorbidity index (
      • Charlson M
      • Szatrowski TP
      • Peterson J.
      Validation of a combined comorbidity index.
      ), the severity of illness at admission, previous use of other drugs, and period of chloroquine adoption by the MoH) were used to estimate the association between CQ/HCQ + AZ use and cure rate as well as the mortality rate. The association between CQ/HCQ + AZ use and the rate of worsening and/or transfer to the ICU was estimated using Poisson regression. These unadjusted and adjusted models were then stratified according to the type of follow-up (inpatients and outpatients). In addition, to account for the nonrandomized administration of the CQ/HCQ + AZ, propensity score matching method was used to reduce confounding effects. In the propensity score matching analysis, the “nearest neighbor” matching method was applied to create a matched control sample. Individual propensities to receive chloroquine treatment were estimated using a multivariate logistic regression model. The propensity score was based on the following variables: age, sex, SaO2, Charlson comorbidity index, and history of chloroquine or antibiotic use. From the matched sample, we performed a secondary analysis (multivariate Cox proportional hazards regression analysis) using the propensity-matched sample. For the models, complete case analysis was performed.
      The statistical analyses were performed with the R software, version 4.1.1 (R Project for Statistical Computing).

      Ethical aspects

      The Burkina Faso Health Research Ethics Committee approved the research protocol on June 10, 2020, under deliberation no. 2020-000101/MS/MESRSI/CERS.

      Results

      Characteristics of the Cohort

      A total of 863 patients attending the COVID-19 case management centers in Ouagadougou and Bobo-Dioulasso between March 9, 2020, and October 31, 2020, were included in the study. Of them, about 50% (432/863) were followed at home and the other half were inpatients admitted at the hospital. Of the patients included, 83.3% (746/863) received CQ/HCQ + AZ treatment and 13.7% (118/863) did not. Among the inpatients, 80.3% were treated with CQ/HCQ + AZ, whereas 92.4% of the patients followed at home received CQ/HCQ + AZ treatment. About 35.1% of study participants were women (p = 0.016). The mean age of patients was estimated at 42.2 years (SD = 15.7). Patients who received CQ/HCQ + AZ had a higher mean age than the untreated group (46 vs 39 years, p <0.001).
      About 84.0% of the patients had a good general condition at admission, whereas 8.6% (37/432) had a poor general condition. The mean oxygen saturation (SaO2) was estimated at 97.0% (SD = 7.2). The main clinical signs presented by the patients at admission were cough (29.7%), general malaise (18.3%), headache (13.1%), shortness of breath (12.9%), myalgias (9.5%), arthralgias (9.5%), and rhinorrhea (7.8%). The other signs or symptoms are listed in the Table 2 below.
      Table 2Measured vital signs and reported clinical signs at admission.
      Vital signs/clinical signsOverallHCQ/CQ Treatment
      UntreatedTreated
      General condition, n/N (%)<0.001
       Good704/836 (84.2)75/112 (67.0)629/724 (86.9)
       Fair96/836 (11.5)18/112 (16.1)78/724 (10.8)
       Bad36/836 (4.3)19/112 (17.0)17/724 (2.3)
      SaO2, Mean (SD)95.7 (7.2)90.6 (15.0)96.5 (4.6)<0.001
      Temperature (°C), Mean (SD)37.0 (0.6)37.2 (0.9)36.9 (0.6)0.004
      History of fever, n/N (%)239/863 (27.7)49/118 (41.5)190/745 (25.5)<0.001
      Cough, n/N (%)254/856 (29.7)46/114 (40.4)208/742 (28.0)0.031
      Malaise, n/N (%)157/856 (18.3)27/114 (23.7)130/742 (17.5)0.17
      Headache, n/N (%)110/840 (13.1)17/114 (14.9)93/726 (13.3)0.54
      Shortness of breath, n/N (%)110/856 (12.9)26/114 (22.8)84/742 (11.3)0.001
      Myalgia, n/N (%)81/856 (9.5)14/114 (12.3)67/742 (9.0)0.40
      Arthralgia, n/N (%)81/856 (9.5)20/114 (17.5)61/742 (8.2)<0.001
      Rhinorrhea, (runny nose), n/N (%)67/856 (7.8)12/144 (10.5)55/742 (7.4)0.36
      Throat pain, n/N (%)61/856 (7.1)11/114 (9.6)50/742 (6.7)0.34
      Chest pain, n/N (%)53/856 (6.2)11/114 (9.6)42/742 (5.7)0.22
      Anosmia, n/N (%)33/856 (3.9)2/114 (1.8)31/742 (4.2)0.30
      Agueusia, n/N (%)24/856 (2.8)2/114 (1.8)22/742 (3.0)0.76
      Wheezing, n/N (%)4/856 (0.5)2/114 (1.8)2/742 (0.3)0.09
      Charlson comorbidity index, n/N (%)0.043
       0728/856 (85.0)91/114 (79.8)637/742 (85.8)
       1 – 2123/856 (14.4)23/114 (20.2)100/742 (13.5)
       3 – 44/856 (0.5)0/114 (0.0)4/742 (0.5)
      At admission, the documented medical history was balanced between the two groups of patients (treated with CQ/HCQ vs untreated). There were no significant differences between the groups regarding comorbidities. For the Charlson comorbidity index, 14.4% and 0.5% of patients had an index of 1–2 and 3, respectively. Among the 5 most commonly used therapeutic classes, antibiotics were on top level (16%), followed by antipyretics/NSAIDs (10.9%), chloroquine-based drugs (8.2%), antihypertensive drugs (7.2%), and other antimalarials (5.6%).

      Study endpoints

      The primary endpoint of rRT-PCR results was available for 701 patients (81.2%). Among the included patients, 10.9% (94/863) worsened or have been admitted to an ICU and 48 died.
      The median time to recovery was estimated at 14 days (95% CI 12–15) and 11 days (95% CI 10 to 12), respectively, for the untreated and treated groups. In the crude unadjusted analysis, patients who had received CQ/HCQ + AZ were more likely to have a short rRT-PCR negativation time than patients who did not (hazard ratio 1.30; 95% CI 1.02–1.65). However, in the Cox multivariable analysis, there was no significant association between CQ/HCQ + AZ use and time to recovery (hazard ratio 1.15; 95% CI 0.89–1.49). There was no statistical association between time to recovery and the use of CQ/HCQ + AZ irrespective of the type of follow-up (outpatient or inpatient) (Figure S1). After using the propensity score-matched samples, the Cox multivariable analysis confirmed the absence of statistical association between the use of CQ/HCQ + AZ and recovery time.
      Throughout the follow-up, 10.1% (75/745) and 16.1% (19/118) experienced a worsening of their clinical conditions in the CQ/HCQ group and in the non-CQ/HCQ group, respectively. Crude and adjusted analysis (and stratified by type of follow-up) to assess association between patients who received CQ/HCQ and the rate of disease worsening or ICU transfer seemed to show a decrease in the rate of ICU transfer (especially in the outpatient group), but this was not statistically significant (Table S1). After controlling for the period of chloroquine uptake (before vs after) in the adjusted Poisson regression, treatment with CQ/HCQ did not show a statistically significant association (odds ratio 0.76; 95% CI 0.43–1.30).
      Table 3.
      Table 3Statistical associations between chloroquine or hydroxychloroquine use and rRT-PCR negativation, worsening, and death in crude analysis, multivariable analysis, and propensity score analyses.
      Analysis itemsRecoveryWorseningDeath
      No. of events/no. of patients at risk (%)
       Treated with HCQ/CQ60875/745 (10.1)20/336 (5.9)
       Not treated with HCQ/CQ7319/118 (16.1)24/73 (32.9)
      Measures of association (95% CI)
       Crude analysis1.30 (1.02–1.65)
      Hazard ratio; ‡ Incidence Rate Ratios.
      0.62 (0.38–1.03)0.15 (0.08–0.27)
      Hazard ratio; ‡ Incidence Rate Ratios.
       Multivariate analysis1.25 (0.97–1.62)
      Hazard ratio; ‡ Incidence Rate Ratios.
      0.72 (0.43–1.30)0.22 (0.10–0.46)
      Hazard ratio; ‡ Incidence Rate Ratios.
       Multivariate analysis adjusted by timing of HCQ/CQ adoption1.15 (0.89–1.49)
      Hazard ratio; ‡ Incidence Rate Ratios.
      0.80 (0.50–1.50)0.20 (0.10–0.44)
      Hazard ratio; ‡ Incidence Rate Ratios.
      Propensity-score analysis
       No. of events/no. of patients at risk (%)
        Treated with HCQ/CQ673/67 (6.0)0/71 (0.0)
        Not treated with HCQ/CQ674/67 (4.5)22/71 (31.0)
       Measures of association (95% CI)
        With matching1.31 (0.72–2.40)
      Hazard ratio; ‡ Incidence Rate Ratios.
        Adjusted for propensity score1.44 (0.76–2.71)
      Hazard ratio; ‡ Incidence Rate Ratios.
      Adjusted for age, history of chloroquine, antibiotic, antimalarial drug use, Charlson comorbidity index, general condition at inclusion, and timing of chloroquine adoption.
      Hazard ratio; ‡ Incidence Rate Ratios.
      Of the 44 deaths, 68.2% (30/44) were in bad general conditions at admission. Of them, 45.4% (20/44) were recorded in the CQ + AZ treatment group. Compared with the untreated group, the treated group had lower probability (log-rank test, p <0.001) of death (Figure 1). Similarly, after controlling for the period of adoption of chloroquine-based treatment (before vs after the introduction of CQ/HCQ in the treatment policy), as well as age, history of drug use (chloroquine, antibiotic, and antimalarial), Charlson comorbidity index, and general conditions at inclusion, the association between mortality and CQ/HCQ treatment was consistent with the crude results (adjusted hazard ratio 0.20; 95% CI 0.10– 0.44).
      Figure 1
      Figure 1Death at 30 days in treated and untreated group.

      Discussion

      Relationship between the use of CQ/HCQ + AZ and virological recovery, disease worsening, and deaths among patients with COVID-19

      Our study showed that the time to viral clearance and risk of worsening or transfer to an ICU were not significantly higher or lower in patients who received CQ/HCQ + AZ than in those who did not. Similar results have also been reported in other studies carried out in several countries worldwide (
      • Chen C
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      • Xiaoye Li
      • Chen Z
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      Safety of hydroxychloroquine in COVID-19 and other diseases: a systematic review and meta-analysis of 53 randomized trials.
      ;
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      Efficacy of chloroquine and hydroxychloroquine in treating COVID-19 infection: A meta-review of systematic reviews and an updated meta-analysis.
      ;
      • Elavarasi A
      • Prasad M
      • Seth T
      • Sahoo RK
      • Madan K
      • Nischal N
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      Chloroquine and Hydroxychloroquine for the Treatment of COVID-19: a Systematic Review and Meta-analysis.
      ;
      • Eze P
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      Efficacy and safety of chloroquine and hydroxychloroquine for treatment of COVID-19 patients-a systematic review and meta-analysis of randomized controlled trials.
      ;
      • Fiolet T
      • Guihur A
      • Rebeaud ME
      • Mulot M
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      Effect of hydroxychloroquine with or without azithromycin on the mortality of coronavirus disease 2019 (COVID-19) patients: a systematic review and meta-analysis.
      ;
      • Maraolo AE
      • Grossi A.
      Safety of hydroxychloroquine for treatment or prevention of SARS-CoV-2 infection: A rapid systematic review and meta-analysis of randomized clinical trials.
      ;
      • Mittal N
      • Mittal R
      • Gupta M
      • Kaushal J
      • Chugh A
      • Khera D
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      Systematic review and meta-analysis of efficacy and safety of hydroxychloroquine and chloroquine in the treatment of COVID-19.
      ). Consistent with other studies, the overall mortality over our study period was significantly lower in the CQ/HCQ + AZ group (
      • Arshad S
      • Kilgore P
      • Chaudhry ZS
      • Jacobsen G
      • Wang DD
      • Huitsing K
      • et al.
      Treatment with hydroxychloroquine, azithromycin, and combination in patients hospitalized with COVID-19.
      ;
      • Ayerbe L
      • Risco-Risco C
      • Ayis S.
      The association of treatment with hydroxychloroquine and hospital mortality in COVID-19 patients.
      ;
      • Bernaola N
      • Mena R
      • Bernaola A
      • Carballo C
      • Lara A
      • Bielza C
      • et al.
      Observational study of the efficiency of treatments in patients hospitalized with Covid-19 in Madrid.
      ;
      • Catteau L
      • Dauby N
      • Montourcy M
      • Bottieau E
      • Hautekiet J
      • Goetghebeur E
      • et al.
      Low-dose hydroxychloroquine therapy and mortality in hospitalised patients with COVID-19: a nationwide observational study of 8075 participants.
      ;
      • Lagier JC
      • Million M
      • Gautret P
      • Colson P
      • Cortaredona S
      • Giraud-Gatineau A
      • et al.
      Outcomes of 3,737 COVID-19 patients treated with hydroxychloroquine/azithromycin and other regimens in Marseille, France: A retrospective analysis.
      ;
      • MILLION M
      • LAGIER J-C
      • TISSOT-DUPONT H
      • RAVAUX I
      • DHIVER C
      • TOMEI C
      • et al.
      Early combination therapy with hydroxychloroquine and azithromycin reduces mortality in 10,429 COVID-19 outpatients.
      ;
      • Yu B
      • Li C
      • Chen P
      • Zhou N
      • Wang L
      • Li J
      • et al.
      Low dose of hydroxychloroquine reduces fatality of critically ill patients with COVID-19.
      ); although the sample selection in our study did not allow for propensity score-adjusted analysis of risk of death, making it difficult to conclude in one direction or the other. However, it is important to stress that the introduction of chloroquine-based treatment for the management of COVID-19 cases in Burkina Faso occurred in a context of improved knowledge of SARS-CoV-2, both internationally and nationally, which may have resulted in a better organization of the response through improved medical practices. Our study (comparison of survival curves between the periods before and after the introduction of CQ/HCQ + AZ in the treatment policy), did not show a statistically significant decrease or increase in mortality attributable to the post-adoption period (April 07, 2020–October 31, 2020) of CQ/HCQ.
      With an observational design and a relatively large confidence intervals, this study could not be considered to exclude the benefits or harms of CQ/HCQ + AZ treatment. Indeed, referring to published research on the same topic, several observational cohort studies have shown conflicting results. Some have shown a decrease in mortality that could be attributed to the use of HCQ (
      • Arshad S
      • Kilgore P
      • Chaudhry ZS
      • Jacobsen G
      • Wang DD
      • Huitsing K
      • et al.
      Treatment with hydroxychloroquine, azithromycin, and combination in patients hospitalized with COVID-19.
      ;
      • Ayerbe L
      • Risco-Risco C
      • Ayis S.
      The association of treatment with hydroxychloroquine and hospital mortality in COVID-19 patients.
      ;
      • Bernaola N
      • Mena R
      • Bernaola A
      • Carballo C
      • Lara A
      • Bielza C
      • et al.
      Observational study of the efficiency of treatments in patients hospitalized with Covid-19 in Madrid.
      ;
      • Di Castelnuovo A
      • Bonaccio M
      • Costanzo S
      • Gialluisi A
      • Antinori A
      • Berselli N
      • et al.
      Common cardiovascular risk factors and in-hospital mortality in 3,894 patients with COVID-19: survival analysis and machine learning-based findings from the multicentre Italian CORIST Study.
      ;
      • Catteau L
      • Dauby N
      • Montourcy M
      • Bottieau E
      • Hautekiet J
      • Goetghebeur E
      • et al.
      Low-dose hydroxychloroquine therapy and mortality in hospitalised patients with COVID-19: a nationwide observational study of 8075 participants.
      ;
      • Lagier JC
      • Million M
      • Gautret P
      • Colson P
      • Cortaredona S
      • Giraud-Gatineau A
      • et al.
      Outcomes of 3,737 COVID-19 patients treated with hydroxychloroquine/azithromycin and other regimens in Marseille, France: A retrospective analysis.
      ), while others have shown no difference (
      • Baguiya A
      • Poda A
      • Cissé K
      • Sondo AK
      • Ouedraogo B
      • Ouedraogo AR
      • et al.
      Effect of Hydroxychloroquine or Chloroquine and Azithromycin on COVID-19 Patients’ Recovery and Mortality: Evidence from a Hospital Based Retrospective Cohort Study Conducted in Burkina Faso.
      ;
      • Geleris J
      • Sun Y
      • Platt J
      • Zucker J
      • Baldwin M
      • Hripcsak G
      • et al.
      Observational Study of Hydroxychloroquine in Hospitalized Patients with Covid-19.
      ;
      • Ip A
      • Berry DA
      • Hansen E
      • Goy AH
      • Pecora AL
      • Sinclaire BA
      • et al.
      Hydroxychloroquine and tocilizumab therapy in COVID-19 patients-An observational study.
      ;
      • Lammers AJJ
      • Brohet RM
      • Theunissen REP
      • Koster C
      • Rood R
      • Verhagen DWM
      • et al.
      Early hydroxychloroquine but not chloroquine use reduces ICU admission in COVID-19 patients.
      ;
      • Rosenberg ES
      • Dufort EM
      • Udo T
      • Wilberschied LA
      • Kumar J
      • Tesoriero J
      • et al.
      Association of Treatment with Hydroxychloroquine or Azithromycin with In-Hospital Mortality in Patients with COVID-19 in New York State.
      ;
      • Sbidian E
      • Josse J
      • Lemaitre G
      • Meyer I
      • Bernaux M
      • Gramfort A
      • et al.
      Hydroxychloroquine with or without azithromycin and in-hospital mortality or discharge in patients hospitalized for COVID-19 infection: A cohort study of 4,642 in-patients in France.
      ;
      • Singh S
      • Khan A
      • Chowdhry M
      • Chatterjee A.
      Outcomes of hydroxychloroquine treatment among hospitalized COVID-19 patients in the united states- real-world evidence from a federated electronic medical record network.
      ). Randomized clinical trials that minimize unmeasured confounding and bias are the best approaches for determining whether a benefit can be attributed to a given therapeutic intervention. Thus, the RECOVERY randomized clinical trial that investigated the efficacy of HCQ on mortality concluded that there was no significant difference between standard treatments (25% mortality) and HCQ treatment (26.8% mortality) (The RECOVERY Collaborative
      • Group The RECOVERY Collaborative
      Effect of Hydroxychloroquine in Hospitalized Patients with Covid-19.
      ).

      Weighting to be done in this study

      Although this study has provided additional insight into the use of CQ/HCQ + AZ as a treatment for COVID-19 in sub-Saharan Africa, it had several weaknesses that were primarily inherent to its design. Indeed, the lack of a priori designing of methodological criteria such as patient follow-up criteria and the lack of standardization of practices (in the different COVID-19 case management centers, including home follow-up) suggested numerous biases and confounding factors. First of all, as most infected patients in the African context are asymptomatic, it is possible that many infected patients did not visit the health centers at the infection onset, which may lead to over- or underestimation of the statistical relationships that the study postulates. Second, similar to the hypothesized relationship between the implementation of the treatment regimen and the reduction of severe cases or mortality, patient-related factors and/or factors related to the characteristics of the medical management, the quality and reliability of the diagnostic, and therapeutic approach including the follow-up could influence the occurrence of symptoms attributed to COVID-19 and/or their worsening and/or viral clearance. Third, information bias could arise from the definition of virological recovery, worsening, or death attributable to COVID-19. Furthermore, although the time (in days) from the diagnosis to the confirmation of virological recovery by rRT-PCR was similar in both groups, it should be noted that the date of the rRT-PCR result release varied between 48 and 72 hours. Only the date of the result (without the date of sampling) was recorded in the patient's records. This could extend the time of the patient's recovery. A fourth limitation of this study could also come from the adherence of the CQ/HCQ treatment, particularly for patients followed at home.
      Nevertheless, the results of this study and the recommendations that follow are to be considered within the framework of scientific presumption and not that of firmly scientific evidence.

      Conclusion

      This observational study provided valuable additional information on the use of CQ/HCQ in patients with COVID-19 in Burkina Faso and did not show any harmful outcomes of CQ/HCQ + AZ treatment. In accordance with data from several published retrospective studies and in contrast with data from other observational studies and randomized clinical trials on the effectiveness of this combination treatment, our study showed that the use of CQ/HCQ appeared to be associated with a reduced risk of mortality after adjusting for measured potential confounders (propensity score matching not done). However, the observational methodological approach of the study requires that these results be interpreted with caution despite the 95% confidence level of the statistical tests. In the absence of an approach that generates a level A scientific evidence, these results could guide health care decisions that should be made based on bundles of evidence including those from this study.

      Acknowledgments

      We thank all the participants in the study and the staff of the two participating University hospitals (Tengandogo and Sourou Sanon). The study was funded by the Fond National de la Recherche et de l'Innovation pour le Developpement (FONRID) from Burkina Faso Ministry of Higher Education, Scientific Research, and Innovation (MESRSI).
      The Burkina Faso CHLORAZ Study Group included the Centre Hospitalier Universitaire de Tengandogo team (Pr Sanou Adama, Dr Abdoul Risgou Ouedraogo, Dr Konate Lassina, Dr Diallo Issa, Dr Some Hippolyte, Dr Rouamba Nadège, Dr Sere Lassina, Dr Yanogo Donald, Mr GuigmA Nicolas, Mr Kabre Moussa, and Mr Bado Gnaboe Maurice). The Clinique Princesse Sarah team (Dr Minoungou Jules Christian W, Dr Zida Justin, Dr Barro Djamilatou, Dr Illa Joseph, Dr Kambou Bruno, Dr Ilboudo David, Dr Ki Ghislain, DR Agbodossindji Fiacre, Dr Gnamou Arouna, Mr Kawane Justine, and Mr Kafando Mathieu). The district sanitaire de Pissy team (Dr Tiemtore Ousseni, Dr Sow Abobacar, Dr Seydou Zida, and Mr Banhoro Honore Achille). The Equipe mobile team (Dr Kabore Mikaila, Dr Nana Harouna). The Clinical Research Unit of Nanoro (Mr Hien S. Franck). The Centre Muraz/Institut National de Santé Publique team (Zoma Aristide). Service des maladies infectieuses team (Boly Raïnatou). Médecine Interne, Centre Hospitalier Universitaire de Sourou Sanon, Bobo-Dioulasso team (Nignan Issan Urbain). Service de pneumologie, Centre Hospitalier Universitaire de Sourou Sanon, Bobo-Dioulasso, Burkina Faso (Ouedraogo Patricia Roseline).

      Funding

      This work was supported by the Fonds National de la Recherche et de l'Innovation pour le Devéloppement (FONRID), Burkina Faso [grant numbers PO 05-2_COVID_FONRID].

      Competing interests

      The authors declare that they have no competing interests.

      Data sharing

      Anonymized participant data could be made available upon requests directed to the corresponding author. If agreed, data can be shared through a secure online platform after signing a data transfer agreement.

      Contributions

      All authors conceived the study, carried out the analysis, wrote the draft, discussed the results, revised the manuscript critically, and approved it for publishing.

      Ethics approval

      This study was approved by the National Ethics Committee (Deliberation number: 2020-000101/MS/MESRSI/CERS) and was registered on ClinicalTrials.gov (NCT04445441).

      Consent for publication

      Not applicable.

      Appendix. Supplementary materials

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