Is metformin use associated with low mortality in patients with type 2 diabetes mellitus hospitalized for COVID-19? a multivariable and propensity score-adjusted meta-analysis

{ 'indexed': {'date-parts': [[2023, 2, 24]], 'date-time': '2023-02-24T05:21:00Z', 'timestamp': 1677216060751}, 'reference-count': 46, 'publisher': 'Public Library of Science (PLoS)', 'issue': '2', 'license': [ { 'start': { 'date-parts': [[2023, 2, 23]], 'date-time': '2023-02-23T00:00:00Z', 'timestamp': 1677110400000}, 'content-version': 'vor', 'delay-in-days': 0, 'URL': 'http://creativecommons.org/licenses/by/4.0/'}], 'content-domain': {'domain': ['www.plosone.org'], 'crossmark-restriction': False}, 'abstract': '<jats:sec id="sec001">\n' '<jats:title>Background</jats:title>\n' '<jats:p>Coronavirus disease 2019 (COVID-19) is a new pandemic that the entire world is facing ' 'since December of 2019. Increasing evidence has shown that metformin is linked to favorable ' 'outcomes in patients with COVID-19. The aim of this study was to address whether outpatient ' 'or inpatient metformin therapy for type 2 diabetes mellitus is associated with low ' 'in-hospital mortality in patients hospitalized for COVID-19.</jats:p>\n' '</jats:sec>\n' '<jats:sec id="sec002">\n' '<jats:title>Methods</jats:title>\n' '<jats:p>We searched studies published in PubMed, Embase, Google Scholar and Cochrane Library ' 'up to November 1, 2022. Raw event data extracted from individual study were pooled using the ' 'Mantel-Haenszel approach. Odds ratio (OR) or hazard ratio (HR) adjusted for covariates that ' 'potentially confound the association using multivariable regression or propensity score ' 'matching was pooled by the inverse-variance method. Random effect models were applied for ' 'meta-analysis due to variance among studies.</jats:p>\n' '</jats:sec>\n' '<jats:sec id="sec003">\n' '<jats:title>Results</jats:title>\n' '<jats:p>Twenty-two retrospective observational studies were selected. The pooled unadjusted ' 'OR for outpatient metformin therapy and in-hospital mortality was 0.48 (95% CI, 0.37–0.62) ' 'and the pooled OR adjusted with multivariable regression or propensity score matching was ' '0.71 (95% CI, 0.50–0.99). The pooled unadjusted OR for inpatient metformin therapy and ' 'in-hospital mortality was 0.18 (95% CI, 0.10–0.31), whereas the pooled adjusted HR was 1.10 ' '(95% CI, 0.38–3.15).</jats:p>\n' '</jats:sec>\n' '<jats:sec id="sec004">\n' '<jats:title>Conclusions</jats:title>\n' '<jats:p>Our results suggest that there is a significant association between the reduction of ' 'in-hospital mortality and outpatient metformin therapy for type 2 diabetes mellitus in ' 'patients hospitalized for COVID-19.</jats:p>\n' '</jats:sec>', 'DOI': '10.1371/journal.pone.0282210', 'type': 'journal-article', 'created': {'date-parts': [[2023, 2, 23]], 'date-time': '2023-02-23T18:31:15Z', 'timestamp': 1677177075000}, 'page': 'e0282210', 'update-policy': 'http://dx.doi.org/10.1371/journal.pone.corrections_policy', 'source': 'Crossref', 'is-referenced-by-count': 0, 'title': 'Is metformin use associated with low mortality in patients with type 2 diabetes mellitus ' 'hospitalized for COVID-19? a multivariable and propensity score-adjusted meta-analysis', 'prefix': '10.1371', 'volume': '18', 'author': [ { 'ORCID': 'http://orcid.org/0000-0002-0381-7804', 'authenticated-orcid': True, 'given': 'Zhiyuan', 'family': 'Ma', 'sequence': 'first', 'affiliation': []}, { 'ORCID': 'http://orcid.org/0000-0002-1132-1788', 'authenticated-orcid': True, 'given': 'Mahesh', 'family': 'Krishnamurthy', 'sequence': 'additional', 'affiliation': []}], 'member': '340', 'published-online': {'date-parts': [[2023, 2, 23]]}, 'reference': [ { 'issue': '18', 'key': 'pone.0282210.ref001', 'doi-asserted-by': 'crossref', 'first-page': '1708', 'DOI': '10.1056/NEJMoa2002032', 'article-title': 'Clinical Characteristics of Coronavirus Disease 2019 in China', 'volume': '382', 'author': 'WJ Guan', 'year': '2020', 'journal-title': 'N Engl J Med'}, { 'key': 'pone.0282210.ref002', 'article-title': 'Characteristics of and Important Lessons From the Coronavirus Disease ' '2019 (COVID-19) Outbreak in China: Summary of a Report of 72314 Cases 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