Tuberc Respir Dis.  2010 Mar;68(3):162-167. 10.4046/trd.2010.68.3.162.

Associated Factor Related to Major Complications of Patients with Hospitalized for 2009 H1N1 Influenza Pneumonia

• Choi SS
• Kim WY
• Kim SH
• Hong SB
• Lim CM
• Koh YS
• Kim W
• Lim KS

• KMID: 1728961
• DOI: http://doi.org/10.4046/trd.2010.68.3.162

Abstract

BACKGROUND
To date, there are few data on the risk factors for severe cases and deaths associated with the 2009 pandemic H1N1 influenza A. Here, we describe the clinical and epidemiologic characteristics of patients hospitalized for pneumonia and identify those factors associated with the development of major complications (MC).
METHODS
We reviewed the medical records of 41 cases of pneumonia admitted to a university-affiliated tertiary hospital between Aug 26 and Dec 10, 2009, and who had confirmed H1N1 influenza A based on real-time reverse transcriptase-polymerase-chain-reaction assay. There were 7,962 patients that fit these criteria. We compared the clinical features and demographic characteristics of patients who developed MC to with those who did not develop MC.
RESULTS
During the study period, 10 patients developed MC (required admission to the intensive care unit, n=10; required ventilator therapy, n=6; death, n=4). Patients with MC were significantly older than those without MC and more frequently had underlying medical conditions (90.0% vs 41.9%, p-value <0.01). In the patients with developed MC, the median PaO2/FiO2 ratio of 230.0 (145.0~347.3) at admission and pneumonia severity index (PSI) score of 141.5 (88.3~158.5) were higher than patients without MC. However, no differences were observed in laboratory findings or in viral shedding between the 2 groups.
CONCLUSION
In hospitalized pneumonia patients of 2009 H1N1 influenza, old age, a history of malignancy, initial hypoxemia, PaO2/FiO2 ratio, and PSI score appear to be risk factor significantly related to developing MC. These findings might be the basis to influence strategies for admitting patients to an intensive or intermediate care unit and for pre-emptive antiviral therapy.

Keyword

Influenza A Virus, H1N1 Subtype; Pneumonia; Critical Illness; Risk Factors

MeSH Terms

Anoxia
Critical Illness
Humans
Influenza A Virus, H1N1 Subtype
Influenza, Human
Intensive Care Units
Medical Records
Pandemics
Pneumonia
Risk Factors
Tertiary Care Centers
Ventilators, Mechanical
Virus Shedding

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