Predictors of Death in Patients with H۱N۱ Influenza: A Retrospective Analytical Study

Aims: Influenza A virus subtype H۱N۱, known as H۱N۱ influenza virus, could cause moderate to severe swine influenza in humans. H۱N۱ influenza is associated with high mortality rate. Effective symptom management could significantly reduce the mortality rate. This study aimed to determine the clinical manifestations, outcomes, and predictors of mortality in patients with H۱N۱ influenza, admitted to hospitals during January to September ۲۰۱۶.Materials & Methods: This retrospective descriptive-analytical study was conducted during January to September ۲۰۱۶ in eight hospitals located in Razavi Khorasan province, northeastern Iran. The medical records of ۶۵ patients were retrieved, and the necessary data were extracted from the records using a demographic questionnaire and a clinical manifestations checklist. The SPSS software Version ۲۳.۰ was used to analyze the data via the measures of descriptive statistics and the logistic regression analysis with odds ratio.findings: The most common clinical manifestations of H۱N۱ influenza were headache (۷۰.۸%), numbness in the extremities (۶۳.۱%), myalgia (۶۰%), cough (۵۸.۵%), fever and shivering (۵۳.۸%), and nausea (۵۳.۸%). In total, ۱۴ (۲۱.۵۳%) patients had died due to H۱N۱ influenza. The significant predictors of death were dyspnea (OR: ۱۳.۹۱, p: .۰۳۲), myalgia (OR: ۰.۰۴. p: .۰۱۰), and age (OR: ۱.۰۵, p: .۰۲۴) so that dyspnea and myalgia were associated with ۱۳.۹ and ۰.۰۴ times higher odds of death, respectively. Moreover, each one year increase in age was associated with ۵% increase in the odds of experiencing death.Conclusions: In the case of H۱N۱ influenza epidemics, care services need to be allocated more to patients who have higher age and suffer from myalgia and dyspnea.

Keywords:

Influenza A virus , H۱N۱ subtype , Risk factors , Mortality