J Korean Med Sci.  2011 Apr;26(4):499-506. 10.3346/jkms.2011.26.4.499.

A Prediction Rule to Identify Severe Cases among Adult Patients Hospitalized with Pandemic Influenza A (H1N1) 2009

• Oh WS
• Lee SJ
• Lee CS
• Hur JA
• Hur AC
• Park YS
• Heo ST
• Bae IG
• Park SW
• Kim ES
• Kim HB
• Song KH
• Lee KS
• Lee SR
• Yeom JS
• Lee SJ
• Kim BN
• Kwak YG
• Lee JH
• Kim YK
• Kim HY
• Kim NJ
• Oh MD

• KMID: 1777879
• DOI: http://doi.org/10.3346/jkms.2011.26.4.499

Abstract

The purpose of this study was to establish a prediction rule for severe illness in adult patients hospitalized with pandemic influenza A (H1N1) 2009. At the time of initial presentation, the baseline characteristics of those with severe illness (i.e., admission to intensive care unit, mechanical ventilation, or death) were compared to those of patients with non-severe illnesses. A total of 709 adults hospitalized with pandemic influenza A (H1N1) 2009 were included: 75 severe and 634 non-severe cases. The multivariate analysis demonstrated that altered mental status, hypoxia (PaO2/FiO2 < or = 250), bilateral lung infiltration, and old age (> or = 65 yr) were independent risk factors for severe cases (all P < 0.001). The area under the ROC curve (0.834 [95% CI, 0.778-0.890]) of the number of risk factors were not significantly different with that of APACHE II score (0.840 [95% CI, 0.790-0.891]) (P = 0.496). The presence of > or = 2 risk factors had a higher sensitivity, specificity, positive predictive value and negative predictive value than an APACHE II score of > or = 13. As a prediction rule, the presence of > or = 2 these risk factors is a powerful and easy-to-use predictor of the severity in adult patients hospitalized with pandemic influenza A (H1N1) 2009.

Keyword

pandemic influenza A (H1N1) 2009; Severity; Risk Factors; Prediction Rule

MeSH Terms

APACHE
Adult
Aged
Antiviral Agents/therapeutic use
Female
Hospitalization
Humans
Influenza A Virus, H1N1 Subtype/*isolation & purification
Influenza, Human/drug therapy/*epidemiology/mortality
Intensive Care Units
Male
Middle Aged
Pandemics
Predictive Value of Tests
ROC Curve
Respiration, Artificial
Risk Factors
Severity of Illness Index

Figure

• 

  Fig. 1 Receiver operating characteristic (ROC) curves for the number of risk factors and APACHE II score. The areas under the ROC curves are 0.834 (95% confidence interval [CI], 0.778-0.890) for the number of risk factors and 0.840 (95% CI, 0.790-0.891) for the APACHE II score (P = 0.496 for each pairwise comparison).

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