{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T04:59:02Z","timestamp":1787893142468,"version":"build-2784847793"},"reference-count":32,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2021,2,5]],"date-time":"2021-02-05T00:00:00Z","timestamp":1612483200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2021,3,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>Seasonal influenza remains a global health problem; however, there are limited data on the specific relative risks for pneumonia and death among outpatients considered to be at high risk for influenza complications. This population-based study aimed to develop prediction models for determining the risk of influenza-related pneumonia and death.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>We included patients diagnosed with laboratory-confirmed influenza between 2016 and 2017 (main cohort, n = 25 659), those diagnosed between 2015 and 2016 (validation cohort 1, n = 16 727), and those diagnosed between 2017 and 2018 (validation cohort 2, n = 34 219). Prediction scores were developed based on the incidence and independent predictors of pneumonia and death identified using multivariate analyses, and patients were categorized into low-, medium-, and high-risk groups based on total scores.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>In the main cohort, age, gender, and certain comorbidities (dementia, congestive heart failure, diabetes, and others) were independent predictors of pneumonia and death. The 28-day pneumonia incidence was 0.5%, 4.1%, and 10.8% in the low-, medium-, and high-risk groups, respectively (c-index, 0.75); the 28-day mortality was 0.05%, 0.7%, and 3.3% in the low-, medium-, and high-risk groups, respectively (c-index, 0.85). In validation cohort 1, c-indices for the models for pneumonia and death were 0.75 and 0.87, respectively. In validation cohort 2, c-indices for the models were 0.74 and 0.87, respectively.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>We successfully developed and validated simple-to-use risk prediction models, which would promptly provide useful information for treatment decisions in primary care settings.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1093\/ofid\/ofab068","type":"journal-article","created":{"date-parts":[[2021,2,6]],"date-time":"2021-02-06T05:33:59Z","timestamp":1612589639000},"source":"Crossref","is-referenced-by-count":15,"title":["Risk Factors for Pneumonia and Death in Adult Patients With Seasonal Influenza and Establishment of Prediction Scores: A Population-Based Study"],"prefix":"10.1093","volume":"8","author":[{"given":"Koichi","family":"Miyashita","sequence":"first","affiliation":[{"name":"Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Japan"},{"name":"Research Support Center, Shizuoka General Hospital, Shizuoka, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eiji","family":"Nakatani","sequence":"additional","affiliation":[{"name":"Research Support Center, Shizuoka General Hospital, Shizuoka, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5439-1543","authenticated-orcid":false,"given":"Hironao","family":"Hozumi","sequence":"additional","affiliation":[{"name":"Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoko","family":"Sato","sequence":"additional","affiliation":[{"name":"Research Support Center, Shizuoka General Hospital, Shizuoka, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshiki","family":"Miyachi","sequence":"additional","affiliation":[{"name":"Research Support Center, Shizuoka General Hospital, Shizuoka, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takafumi","family":"Suda","sequence":"additional","affiliation":[{"name":"Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2021,2,5]]},"reference":[{"key":"2021031212394670900_CIT0001","doi-asserted-by":"crossref","first-page":"697","DOI":"10.1016\/S0140-6736(17)30129-0","article-title":"Influenza","volume":"390","author":"Paules","year":"2017","journal-title":"Lancet"},{"key":"2021031212394670900_CIT0002","doi-asserted-by":"crossref","first-page":"e1","DOI":"10.1093\/cid\/ciy866","article-title":"Clinical practice guidelines by the Infectious 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