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We conducted this systematic review and meta-analysis to have a better understanding of the clinical characteristics of older COVID-19 patients.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A systematic search of PubMed and Scopus was performed from December 2019 to May 3rd, 2020. Observational studies including older adults (age\u2009\u2265\u200960\u2009years) with COVID-19 infection and reporting clinical characteristics or outcome were included. Primary outcome was assessing weighted pooled prevalence (WPP) of severity and outcomes. Secondary outcomes were clinical features including comorbidities and need of respiratory support.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Result<\/jats:title>\n                    <jats:p>\n                      Forty-six studies with 13,624 older patients were included. Severe infection was seen in 51% (95% CI\u2013 36-65%,\n                      <jats:italic>I<\/jats:italic>\n                      <jats:sup>\n                        <jats:italic>2<\/jats:italic>\n                      <\/jats:sup>\n                      \u201395%) patients while 22% (95% CI\u2013 16-28%,\n                      <jats:italic>I<\/jats:italic>\n                      <jats:sup>\n                        <jats:italic>2<\/jats:italic>\n                      <\/jats:sup>\n                      \u201388%) were critically ill. Overall, 11% (95% CI\u2013 5-21%,\n                      <jats:italic>I<\/jats:italic>\n                      <jats:sup>\n                        <jats:italic>2<\/jats:italic>\n                      <\/jats:sup>\n                      \u201398%) patients died. The common comorbidities were hypertension (48, 95% CI\u2013 36-60%\n                      <jats:italic>I<\/jats:italic>\n                      <jats:sup>\n                        <jats:italic>2<\/jats:italic>\n                      <\/jats:sup>\n                      \u201392%), diabetes mellitus (22, 95% CI\u2013 13-32%,\n                      <jats:italic>I<\/jats:italic>\n                      <jats:sup>\n                        <jats:italic>2<\/jats:italic>\n                      <\/jats:sup>\n                      \u201386%) and cardiovascular disease (19, 95% CI \u2013 11-28%,\n                      <jats:italic>I<\/jats:italic>\n                      <jats:sup>\n                        <jats:italic>2<\/jats:italic>\n                      <\/jats:sup>\n                      <jats:italic>\u2013<\/jats:italic>\n                      85%). Common symptoms were fever (83, 95% CI\u2013 66-97%,\n                      <jats:italic>I<\/jats:italic>\n                      <jats:sup>\n                        <jats:italic>2<\/jats:italic>\n                      <\/jats:sup>\n                      \u201391%), cough (60, 95% CI\u2013 50-70%,\n                      <jats:italic>I<\/jats:italic>\n                      <jats:sup>\n                        <jats:italic>2<\/jats:italic>\n                      <\/jats:sup>\n                      \u201371%) and dyspnoea (42, 95% CI\u2013 19-67%,\n                      <jats:italic>I<\/jats:italic>\n                      <jats:sup>\n                        <jats:italic>2<\/jats:italic>\n                      <\/jats:sup>\n                      \u201394%). Overall, 84% (95% CI\u2013 60-100%,\n                      <jats:italic>I<\/jats:italic>\n                      <jats:sup>\n                        <jats:italic>2<\/jats:italic>\n                      <\/jats:sup>\n                      \u201381%) required oxygen support and 21% (95% CI\u2013 0-49%,\n                      <jats:italic>I<\/jats:italic>\n                      <jats:sup>\n                        <jats:italic>2<\/jats:italic>\n                      <\/jats:sup>\n                      \u201391%) required mechanical ventilation. Majority of studies had medium to high risk of bias and overall quality of evidence was low for all outcomes.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Approximately half of older patients with COVID-19 have severe infection, one in five are critically ill and one in ten die. More high-quality evidence is needed to study outcomes in this vulnerable patient population and factors affecting these outcomes.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s12877-021-02261-3","type":"journal-article","created":{"date-parts":[[2021,5,19]],"date-time":"2021-05-19T14:15:28Z","timestamp":1621433728000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":124,"title":["Clinical features and outcomes of COVID-19 in older adults: a systematic review and meta-analysis"],"prefix":"10.1186","volume":"21","author":[{"given":"Sunny","family":"Singhal","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pramod","family":"Kumar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sumitabh","family":"Singh","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Srishti","family":"Saha","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0979-9413","authenticated-orcid":false,"given":"Aparajit Ballav","family":"Dey","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,5,19]]},"reference":[{"issue":"1","key":"2261_CR1","first-page":"157","volume":"91","author":"D Cucinotta","year":"2020","unstructured":"Cucinotta D, Vanelli M. 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