Zoe X Z Zhang1, Win Mar Kyaw2, Hanley J Ho2, Min Zhi Tay3, Hongjie Huang4, Aung Aung Hein2, Angela Chow2. 1. Department of Epidemiology, Singapore General Hospital, Singapore; Department of Clinical Epidemiology, Office of Clinical Epidemiology, Analytics, and kNowledge (OCEAN), Tan Tock Seng Hospital, Singapore. Electronic address: 0000-0002-7064-3023zoe_zhang_xz@ttsh.com.sg. 2. Department of Clinical Epidemiology, Office of Clinical Epidemiology, Analytics, and kNowledge (OCEAN), Tan Tock Seng Hospital, Singapore. 3. Department of Clinical Epidemiology, Office of Clinical Epidemiology, Analytics, and kNowledge (OCEAN), Tan Tock Seng Hospital, Singapore; Preventive Medicine Residency Programme, National University Health System, Singapore. 4. Department of Epidemiology, Singapore General Hospital, Singapore.
Abstract
BACKGROUND: Seasonal influenza can cause severe illness leading to intensive care unit (ICU) admission and death. OBJECTIVE: To define the clinical and epidemiological features of severe seasonal influenza infection and factors associated with mortality. STUDY DESIGN: A retrospective review was conducted on all patients with laboratory-confirmed influenza infection who were either admitted into the ICU or died in the two largest tertiary hospitals in Singapore from 2011-2015. RESULTS: Of 520 patients included in our study, 423 (81.3%) had influenza A infection and the rest with influenza B. Of patients with influenza A infection, 70.0% (296/423) were subtyped, of whom 24.0% (71/296) had A/H1N1pdm2009 and 76.0% (225/296) had A/H3N2. The median age of patients was 72 years (IQR 61-82). Males constituted 53.1% (276/520). Median Charlson comorbidity index score was 1 (IQR 0-3). About 70% had physical or radiological evidence of pneumonia upon admission. In-hospital mortality was 58.1% (302/520). On multiple logistic regression analysis, factors positively associated with mortality were age ≥65 years (adjusted odds ratio, aOR = 3.64, 95%CI 2.21-5.99, p < 0.001), malignancy (aOR = 2.53, 95%CI 1.12-5.73; p = 0.026), and hypoalbuminemia (aOR = 2.16, 95%CI 1.26-3.73; p = 0.005), while antiviral therapy (aOR = 0.33, 95%CI 0.17-0.63; p < 0.001) and ventilation (aOR = 0.23, 95% CI 0.13-0.39; p < 0.001) were negatively associated. CONCLUSIONS: Patients with severe seasonal influenza infection were characterized by advanced age, hypoalbuminemia and presence of pneumonia on admission. Age ≥65 years, malignancy, and hypoalbuminemia were associated with increased mortality, and antiviral therapy and ventilation with decreased mortality.
BACKGROUND: Seasonal influenza can cause severe illness leading to intensive care unit (ICU) admission and death. OBJECTIVE: To define the clinical and epidemiological features of severe seasonal influenza infection and factors associated with mortality. STUDY DESIGN: A retrospective review was conducted on all patients with laboratory-confirmed influenza infection who were either admitted into the ICU or died in the two largest tertiary hospitals in Singapore from 2011-2015. RESULTS: Of 520 patients included in our study, 423 (81.3%) had influenza A infection and the rest with influenza B. Of patients with influenza A infection, 70.0% (296/423) were subtyped, of whom 24.0% (71/296) had A/H1N1pdm2009 and 76.0% (225/296) had A/H3N2. The median age of patients was 72 years (IQR 61-82). Males constituted 53.1% (276/520). Median Charlson comorbidity index score was 1 (IQR 0-3). About 70% had physical or radiological evidence of pneumonia upon admission. In-hospital mortality was 58.1% (302/520). On multiple logistic regression analysis, factors positively associated with mortality were age ≥65 years (adjusted odds ratio, aOR = 3.64, 95%CI 2.21-5.99, p < 0.001), malignancy (aOR = 2.53, 95%CI 1.12-5.73; p = 0.026), and hypoalbuminemia (aOR = 2.16, 95%CI 1.26-3.73; p = 0.005), while antiviral therapy (aOR = 0.33, 95%CI 0.17-0.63; p < 0.001) and ventilation (aOR = 0.23, 95% CI 0.13-0.39; p < 0.001) were negatively associated. CONCLUSIONS:Patients with severe seasonal influenza infection were characterized by advanced age, hypoalbuminemia and presence of pneumonia on admission. Age ≥65 years, malignancy, and hypoalbuminemia were associated with increased mortality, and antiviral therapy and ventilation with decreased mortality.
Authors: Alvaro Lorente-Ros; Juan Manuel Monteagudo Ruiz; Luis M Rincón; Rodrigo Ortega Pérez; Sonia Rivas; Rafael Martínez-Moya; Maria Ascensión Sanromán; Luis Manzano; Gonzalo Luis Alonso; Borja Ibáñez; Jose Luis Zamorano Journal: Cardiol J Date: 2020-06-26 Impact factor: 2.737