Table 1– Characteristics of patients with clinical success versus clinical failure
VariableClinical successClinical failurep-value
Subjects n8218
Patient characteristics
 Age yrs40.4±17.540.4±161.000
 Age >65 yrs8 (9.8)1 (5.6)1.000
 Female37 (57.3)6 (33.3)0.065
 Pregnant7 (18.9)0 (0.0)0.346
 Breastfeeding2 (2.4)0 (0.0)1.000
 Oseltamivir before admission12 (14.6)5 (27.8)0.183
 Prior influenza vaccination16 (21.3)4 (22.2)1.000
 Smoker15 (18.3)2 (17.7)1.000
History and physical findings
 Exposure history
  Definitive3 (3.7)1 (5.6)0.554
  Possible15 (18.3)2 (11.1)0.730
  Negative64 (78.1)14 (77.8)1.000
 Influenza-like illness
  Fever80 (97.6)17 (94.4)0.452
  Chills37 (45.1)6 (35.3)0.457
  Myalgia60 (73.2)11 (64.7)0.557
  Rhinitis25 (30.5)6 (33.3)0.813
  Headache51 (62.2)6 (35.3)0.041
  Cough75 (91.5)14 (82.4)0.369
  Wheezing27 (32.9)6 (33.3)0.974
  Painful swallowing28 (34.2)7 (41.2)0.588
  Abdominal pain12 (14.6)4 (23.5)0.467
  Diarrhoea12 (14.6)1 (5.9)0.457
 Respiratory compromise
  Respiratory rate ≥30 breaths·min−115 (22.1)14 (77.8)<0.001
  Respiratory rate breaths·min−126±5.736.7±9.1<0.001
  Shortness of breath46 (56.1)16 (94.1)0.003
  Cyanosis4 (4.9)7 (38.9)<0.001
  Crackles43 (52.4)15 (83.3)0.016
  Pa,O2<60 mmHg15 (18.3)16 (88.9)<0.001
  Pulmonary infiltrate59 (72.0)18 (100)0.228
  Multilobar infiltrates31 (50.8)15 (88.2)0.006
  Bilateral infiltrates28 (45.9)15 (88.2)0.002
  Pleural effusion0 (0.0)0 (0.0)
 Other
  Altered mental status1 (1.2)4 (22.2)0.003
  Systolic blood pressure <90 mmHg1 (1.2)1 (5.6)0.329
  Heart rate beats·min−1103.5±19.6112.4±27.80.123
Comorbidities
 Obesity5 (6.1)6 (33.3)0.004
 Cardiac disease10 (12.2)2 (11.1)1.000
 Diabetes13 (15.9)3 (16.7)1.000
 COPD25 (30.5)3 (16.7)0.237
 Liver disease1 (1.2)1 (5.6)0.329
 Kidney disease1 (1.2)2 (11.1)0.083
Laboratory characteristics
 WBC cells·mm−310.2±67.4±3.40.094
 Haematocrit %40.2±4.941.6±8.70.344
 Platelets cells·mm−3242.8±85.5216.7±71.70.215
 Glucose mg·dL−1133.3±52134.7±57.90.897
 Creatinine mg·dL−10.8±0.62.2±2.10.001
  • Data are presented as mean±sd or n (%), unless otherwise stated. Pa,O2: arterial oxygen tension; COPD: chronic obstructive pulmonary disease; WBC: white blood cells.