Table 2.
Characteristics of eligible patients categorised by quadrisected body mass index categories
| Variable | Category | Quadrisected groups based on quartiles of body mass index | P value | |||
|---|---|---|---|---|---|---|
| Low, ≤ 18.5 kg/m2 |
Medium–low, 18.6–21.0 kg/m2 |
Medium–high, 21.1–23.7 kg/m2 |
High, ≥ 23.8 kg/m2 |
|||
| N = 987 | N = 989 | N = 986 | N = 990 | |||
| Age (years) | 85.0 (8.4) | 84.3 (8.6) | 82.3 (8.6) | 81.0 (8.5) | < 0.001 | |
| Male | 482 (48.8%) | 470 (47.5%) | 371 (37.6%) | 409 (41.3%) | < 0.001 | |
| Smoking history | Non-smoker | 639 (64.7%) | 635 (64.2%) | 580 (58.8%) | 586 (59.2%) | 0.006 |
| Current/past smoker | 348 (35.3%) | 354 (35.8%) | 406 (41.2%) | 404 (40.8%) | ||
| Estimated glomerular filtration rate (ml/min/1.73 m2) | 40.6 (13.7) | 40.2 (14.0) | 41.1 (13.4) | 40.3 (13.4) | 0.49 | |
| CKD staging | CKD stage G3 | 766 (77.6%) | 739 (74.7%) | 780 (79.1%) | 769 (77.7%) | 0.39 |
| CKD stage G4 | 162 (16.4%) | 191 (19.3%) | 155 (15.7%) | 166 (16.8%) | ||
| CKD stage G5 | 59 (6.0%) | 59 (6.0%) | 51 (5.2%) | 55 (5.6%) | ||
| Creatinine clearance (ml/min) | 24.3 (9.6) | 29.0 (12.0) | 33.7 (13.0) | 40.4 (16.6) | < 0.001 | |
| Dehydration | 677 (68.6%) | 624 (63.1%) | 578 (58.6%) | 535 (54.0%) | < 0.001 | |
| Respiratory failure | None | 513 (52.0%) | 525 (53.1%) | 562 (57.0%) | 529 (53.4%) | 0.018 |
| Moderate | 313 (31.7%) | 336 (34.0%) | 317 (32.2%) | 335 (33.8%) | ||
| Severe | 161 (16.3%) | 128 (12.9%) | 107 (10.9%) | 126 (12.7%) | ||
| Orientation disturbance | 212 (21.5%) | 184 (18.6%) | 126 (12.8%) | 126 (12.7%) | < 0.001 | |
| Immunosuppression | 154 (15.6%) | 171 (17.3%) | 171 (17.3%) | 168 (17.0%) | 0.70 | |
| Pulmonary consolidation | 245 (24.8%) | 266 (26.9%) | 268 (27.2%) | 254 (25.7%) | 0.60 | |
| Hypotension on admission | 111 (11.2%) | 79 (8.0%) | 51 (5.2%) | 47 (4.7%) | < 0.001 | |
| Pneumonia type | Community-acquired | 900 (91.2%) | 924 (93.4%) | 947 (96.0%) | 953 (96.3%) | < 0.001 |
| Nursing and healthcare-associated | 87 (8.8%) | 65 (6.6%) | 39 (4.0%) | 37 (3.7%) | ||
| Charlson comorbidity index | 1.7 (1.7) | 1.7 (1.6) | 1.7 (1.7) | 1.6 (1.6) | 0.57 | |
Data are presented as mean (standard deviation) for continuous measures and as n (%) for categorical measures
CKD Chronic kidney disease