In Japan, routine use of early antiviral therapy for patients with influenza is standard.
Multicenter prospective cohort evaluation of hospitalized patients with laboratory-confirmed influenza to identify prognostic factors among patients receiving antiviral therapy.
The population included 1345 influenza patients ( 766 pediatric and 579 adult), and excluding those < age 1(not approved for anti-viral therapy) , 97.7% (1224/1253) received antiviral therapy. Among 579 adult patients, 24 (4.1%) died within 30 days , while none of the 766 pediatric patients died. 528 of the adult patients (91.2%) had influenza A, 509 (87.9%) had a chronic underlying illness, 211 (36.4%) had radiographically confirmed pneumonia . 20 of the 24 patients who died, had pneumonia , and the etiologies were: Streptococcus pneumoniae (12.3%), Staphylococcus aureus (10.9%), including methicillin-resistant S. aureus (MRSA) (3.3%), Enterobacteriaceae (8.1%), and Pseudomonas aeruginosa (3.3%). Of these, 151 were classified as community-acquired pneumonia (CAP), and 60 as healthcare-associated pneumonia (HCAP). Inappropriate therapy was more common in HCAP than CAP ( 15.2% vs. 2%, p=0.001). Potential multidrug-resistant (MDR) pathogens were more common ( 21.7%vs 2.6%, p<0.001) in HCAP patients, particularly MRSA (10% vs 0.7%, p=0.002) and Pseudomonas aeruginosa (8.3% vs 1.3%, p=0.021). Using Cox proportional hazards modeling with prescribed independent variables, male gender, severity score, serum albumin (malnutrition), and pneumonia were associated with survival 30 -days from the onset of influenza.
Among the prognostic factors, malnutrition and pneumonia are amenable to medical intervention. There is an opportunity to improve empiric therapy for patients with HCAP and influenza.
Japan Medical Association Center for Clinical Trials JMA-IIA00123.