Influenza A-associated severe pneumonia in hospitalized patients- Risk factors and NAI treatments

Zou Q, Wang X, Liu S, Bao J. Yu F, Wu W, Wang X, Shen, B, Zhou T, Zhao Z, Wang Y, Chen R, Wang W, Ma J, Li Y, Wu X, Shen W, Xie F, Zheng S, Dhanasekaran V, Yu Chen 2020. International Journal of Infectious Diseases 92: 208-213.

Abstract

Objective

The risk factors and the impact of NAI treatments in patients with severe influenza A-associated pneumonia remain unclear.

Methods

A multicenter, retrospective, observational study was conducted in Zhejiang, China during a severe influenza epidemic in August 2017-May 2018. Clinical records of patients (>14 y) hospitalized with laboratory-confirmed influenza A virus infection and who developed severe pneumonia were compared to those with mild-to-moderate pneumonia. Risk factors related to pneumonia severity and effects of NAI treatments (monotherapy and combination of peramivir and oseltamivir) were analyzed.

Results

202 patients with influenza A-associated severe pneumonia were enrolled, of whom 84 (41.6%) had died. Male gender (OR = 1.782; 95% CI: 1.089-2.917; P = 0.022), chronic pulmonary disease (OR = 2.581; 95% CI: 1.447-4.603; P = 0.001) and diabetes mellitus (OR = 2.042; 95% CI: 1.135-3.673; P = 0.017) were risk factors related to influenza A pneumonia severity. In cox proportional hazards model, severe pneumonia patients treated with double dose oseltamivir (300mg/d) had a better survival rate compared to those receiving a single dose (150 mg/d) (HR = 0.475; 95%CI: 0.254-0.887; P = 0.019). However, different doses of peramivir (300 mg/d vs. 600 mg/d) and combination therapy (oseltamivir-peramivir vs. monotherapy) showed no differences in 60-day mortality (P = 0.392 and P = 0.658, respectively).

Conclusions

Patients with male gender, chronic pulmonary disease, or diabetes mellitus were at high risk of developing severe pneumonia after influenza A infection. Double dose oseltamivir might be considered in treating influenza A-associated severe pneumonia.