Hydroxychloroquine in the treatment of outpatients with mildly symptomatic COVID-19: A multi-center observational study

DOI record: { "DOI": "10.1186/s12879-021-05773-w", "ISSN": [ "1471-2334" ], "URL": "http://dx.doi.org/10.1186/s12879-021-05773-w", "abstract": "<jats:title>Abstract</jats:title><jats:sec>\n <jats:title>Background</jats:title>\n <jats:p>Hydroxychloroquine has not been associated with improved survival among hospitalized COVID-19 patients in the majority of observational studies and similarly was not identified as an effective prophylaxis following exposure in a prospective randomized trial. We aimed to explore the role of hydroxychloroquine therapy in mildly symptomatic patients diagnosed in the outpatient setting.</jats:p>\n </jats:sec><jats:sec>\n <jats:title>Methods</jats:title>\n <jats:p>We examined the association between outpatient hydroxychloroquine exposure and the subsequent progression of disease among mildly symptomatic non-hospitalized patients with documented SARS-CoV-2 infection. The primary outcome assessed was requirement of hospitalization. Data was obtained from a retrospective review of electronic health records within a New Jersey USA multi-hospital network. We compared outcomes in patients who received hydroxychloroquine with those who did not applying a multivariable logistic model with propensity matching.</jats:p>\n </jats:sec><jats:sec>\n <jats:title>Results</jats:title>\n <jats:p>Among 1274 outpatients with documented SARS-CoV-2 infection 7.6% were prescribed hydroxychloroquine. In a 1067 patient propensity matched cohort, 21.6% with outpatient exposure to hydroxychloroquine were hospitalized, and 31.4% without exposure were hospitalized. In the primary multivariable logistic regression analysis with propensity matching there was an association between exposure to hydroxychloroquine and a decreased rate of hospitalization from COVID-19 (OR 0.53; 95% CI, 0.29, 0.95). Sensitivity analyses revealed similar associations. QTc prolongation events occurred in 2% of patients prescribed hydroxychloroquine with no reported arrhythmia events among those with data available.</jats:p>\n </jats:sec><jats:sec>\n <jats:title>Conclusions</jats:title>\n <jats:p>In this retrospective observational study of SARS-CoV-2 infected non-hospitalized patients hydroxychloroquine exposure was associated with a decreased rate of subsequent hospitalization. Additional exploration of hydroxychloroquine in this mildly symptomatic outpatient population is warranted.</jats:p>\n </jats:sec>", "alternative-id": [ "5773" ], "article-number": "72", "assertion": [ { "group": { "label": "Article History", "name": "ArticleHistory" }, "label": "Received", "name": "received", "order": 1, "value": "25 August 2020" }, { "group": { "label": "Article History", "name": "ArticleHistory" }, "label": "Accepted", "name": "accepted", "order": 2, "value": "6 January 2021" }, { "group": { "label": "Article History", "name": "ArticleHistory" }, "label": "First Online", "name": "first_online", "order": 3, "value": "14 January 2021" }, { "group": { "label": "Ethics approval and consent to participate", "name": "EthicsHeading" }, "name": "Ethics", "order": 1, "value": "Institutional Review Board approval was obtained for access to the prospective observational database (Hackensack Meridian Health under Study# Pro2020–0342). The requirement for patient informed consent, verbal or written, and HIPAA aurthorization was waived by the IRB as this project represented a non-interventional study utilizing routinely collected data for secondary research purposes." }, { "group": { "label": "Consent for publication", "name": "EthicsHeading" }, "name": "Ethics", "order": 2, "value": "Not applicable." }, { "group": { "label": "Competing interests", "name": "EthicsHeading" }, "name": "Ethics", "order": 3, "value": "<i>Potential conflicts of interest</i>: AHG reports being a study investigator for Genentech-Hoffman La Roche, during the conduct of the study; research funding as study investigator from Acerta, AstraZeneca, Celgene, Kite Pharma, Elsevier’s PracticeUpdate Oncology, Gilead, Medscape, MJH Associates, OncLive Peer Exchange, Physicians Education Resource, and Xcenda, outside the submitted work, and research funding as a study investigator for Constellation, Infinity, Infinity Verastem, Janssen, Karyopharm, and Pharmacyclics, outside of the submitted work.<i>Potential conflicts of interest:</i> EH report consulting for Regional Cancer Care Associates and Hackensack Meridian Health, outside the submitted work.<i>Potential conflicts of interest:</i> ALP and SLG report having equity ownership in COTA, outside the submitted work.<i>No conflicts of interest:</i> AI, JA, YZ, BAS, UB, MM, ISS, JPU, DMW, RP, RLS, MGP, SLC, FJC, AGC, BLP, DR, GEM, MPE, KLZ, and PM." } ], "author": [ { "ORCID": "http://orcid.org/0000-0003-0456-5618", "affiliation": [], "authenticated-orcid": false, "family": "Ip", "given": "Andrew", "sequence": "first" }, { "affiliation": [], "family": "Ahn", "given": "Jaeil", "sequence": "additional" }, { "affiliation": [], "family": "Zhou", "given": "Yizhao", "sequence": "additional" }, { "affiliation": [], "family": "Goy", "given": "Andre H.", "sequence": "additional" }, { "affiliation": [], "family": "Hansen", "given": "Eric", "sequence": "additional" }, { "affiliation": [], 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