Subjects, N | 108 | 1314 | | 431 | |
Baseline characteristics | | | | | |
Mean±sd age at admission (range), years | 73.0±12.9 (30–97) | 68.8±17.5 (19–98) | 0.016 | 68.8±16.7 (19–96) | 0.015 |
Male sex | 52/108 (48) | 734/1314 (56) | | 243/431 (56) | |
Median BMI (IQR), kg·m−2 | 25.0 (22.2–30.9) | 24.6 (21.3–29.0) | 0.107 | 25.0 (21.9–29.5) | 0.500 |
Current smokers | 18/108 (17) | 270/1305 (21) | 0.319 | 86/429 (20) | 0.427 |
Comorbidity | | | | | |
At least one | 97/108 (90) | 1147/1314 (87) | 0.446 | 368/431 (85) | 0.231 |
Chronic respiratory disease | 56/108 (52) | 610/1314 (46) | 0.277 | 166/431 (39) | 0.012 |
Chronic heart disease | 56/108 (52) | 509/1313 (39) | 0.008 | 176/431 (41) | 0.039 |
Diabetes mellitus | 26/108 (24) | 271/1314 (21) | 0.397 | 90/431 (21) | 0.470 |
Chronic renal disease | 20/108 (19) | 193/1314 (15) | 0.284 | 60/431 (14) | 0.229 |
Cancer (solid tumour and haematological malignancy) | 25/107 (23) | 228/1313 (18) | 0.166 | 72/431 (17) | 0.109 |
Other immunodeficiency | 9/108 (8) | 94/1314 (7) | 0.649 | 33/431 (8) | 0.815 |
Cirrhosis | 3/108 (3) | 72/1314 (5) | 0.227 | 20/431 (5) | 0.392 |
Current season influenza vaccination | 63/106 (59) | 665/1307 (51) | 0.090 | 206/428 (48) | 0.037 |
Presence of children <5 years old in household | 10/108 (9) | 86/1313 (7) | 0.281 | 27/430 (6) | 0.274 |
Pre-hospital medication | | | | | |
Immunosuppressive therapy | 10/108 (9) | 119/1309 (9) | 0.953 | 34/429 (8) | 0.651 |
Systemic corticosteroids | 22/108 (20) | 182/1309 (14) | 0.066 | 52/429 (12) | 0.026 |
Inhaled corticosteroids | 32/108 (30) | 267/1309 (20) | 0.024 | 89/429 (21) | 0.048 |
Hospitalisation in the previous 12 months | 46/108 (43) | 623/1308 (48) | 0.314 | 180/429 (42) | 0.905 |
Clinical presentation | | | | | |
Median time from symptom onset to admission (IQR), days | 2 (1–4) | 2 (1–3) | 0.620 | 2 (1–3) | 0.627 |
Symptoms | | | | | |
Fever | 94/108 (87) | 1127/1313 (86) | 0.730 | 381/431 (88) | 0.696 |
Cough | 93/108 (86) | 1026/1313 (78) | 0.052 | 380/430 (88) | 0.519 |
Dyspnoea | 98/108 (91) | 1049/1314 (80) | 0.006 | 306/431 (71) | <0.001 |
Sudden symptom onset | 33/105 (31) | 416/1293 (32) | 0.875 | 156/426 (37) | 0.320 |
Weakness/malaise | 25/105 (24) | 286/1306 (22) | 0.650 | 105/428 (25) | 0.877 |
Headache | 22/107 (21) | 368/1310 (28) | 0.094 | 148/429 (35) | 0.006 |
Myalgia | 19/106 (18) | 335/1310 (26) | 0.080 | 133/429 (31) | 0.008 |
Sore throat | 18/107 (17) | 207/1311 (16) | 0.779 | 83/429 (19) | 0.550 |