Seasonal trend and mortality in adults with viral pneumonia

ABSTRACT

OBJECTIVE: Viral infections are being identified increasingly in patients with pneumonia and can be fatal, particularly in immune-compromised patients. This study examined the seasonal trend and mortality in adult patients with viral pneumonia. METHODS: Retrospective data of adult patients who visited the emergency room and were diagnosed with viral pneumonia was collected between January 2012 and December 2015 at a tertiary referral center. The monthly incidence of each viral pathogen and in-hospital mortality were analyzed. RESULTS: A total of 1,179 patients were analyzed. The mean age was 66.0 years and male comprised 60.0% of cases. Multiple viral infections and viral-bacterial co-infection were found in 5.2% and 24.7% of patients, respectively. The underlying diseases were as follows diabetes mellitus in 32.8%, malignancy in 30.3%, and chronic lung disease in 30.9%. In-hospital mortality occurred in 7.9% of the total patients. Rhinovirus was the most common viral pathogen throughout the year. Influenza A was the most common from January to March and rhinovirus was the most common from September to November. Among the viral pathogens, a coronavirus infection resulted in the highest mortality of 12.6% but there was no significant difference in mortality among the viral pathogens. Multivariate analysis for in-hospital mortality revealed a viral-bacterial co-infection (odds ratio [OR], 1.46; 95% confidence interval [CI], 1.02–2.34), malignancy (OR, 2.34; 95% CI, 1.48–3.71), C-reactive protein (CRP; OR, 1.04; 95% CI, 1.02–1.07), CURB-65 score 2 (OR, 2.46; 95% CI, 1.47–4.12), and CURB-65 score ≥3 (OR, 4.60; 95% CI, 2.31–9.16) to be significantly associated with mortality. CONCLUSION: The outcome from viral pneumonia was poor in adult patients. A viral-bacterial co-infection, malignancy, elevated CRP, and CURB-65 score were significant predictors of mortality.