Table 1.
Baseline characteristics
| Total | < 74 years | > 75 years | P value | |
|---|---|---|---|---|
| No. of patients | 667 | 231 | 436 | |
| died within 30 days | 66 (10.0%) | 11 (4.8%) | 55 (12.6%) | < 0.01* |
| Male / female | 424 (63.6%)/243 (36.4%) | 1 52 (65.8%)/79 (34.2%) | 272 (62.4%)/164 (37.6%) | 0.38 |
| Age(years) | 80.0 (71.0–86.0) | 67.0 (55.0–71.0) | 85.0 (80.0–89.0) | < 0.01* |
| CAP / HCAP | 396 (59.4%)/271 (40.6%) | 1 75 (75.8%)/56 (24.2%) | 221 (50.7%)/21 5 (49.3%) | < 0.01* |
| PSI class | ||||
| I | 35 (5.3%) | 35 (15.1%) | 0 | < 0.01* |
| II | 84 (1 2.6%) | 75 (32.5%) | 9 (2.1%) | |
| III | 151 (22.6%) | 50 (21.6%) | 101 (23.1%) | |
| IV | 288 (43.2%) | 60 (26.0%) | 228 (52.3%) | |
| V | 109 (16.3%) | 11 (4.8%) | 98 (22.4%) | |
| BMI(kg/m2) | 19.8 (17.0–22.5) | 20.0 (17.9–22.7) | 19.6 (16.9–22.5) | 0.10 |
| Albumin(g/dL) | 3.2 (2.8–3.6) | 3.4 (2.9–3.8) | 3.1 (2.7–3.5) | < 0.01* |
| Procalcitonin(ng/mL) | 0.35 (0.10–2.09) | 0.20 (0.07–0.84) | 0.52 (0.13–2.66) | < 0.01* |
| WBC(/mm3) | 10,500 (7700–14,400) | 11,100 (7600–14,800) | 10,300 (7700–13,900) | 0.38 |
| CRP(mg/dL) | 9.09 (3.99–16.20) | 9.91 (4.43–18.0) | 8.01 (3.52–15.01) | < 0.01* |
| BUN(mg/dL) | 18 (14–26) | 14 (10–19) | 20 (15–29) | < 0.01* |
| Comorbidity Charlson comorbidity index | ||||
| 0 | 224 (33.6%) | 104 (45.0%) | 120 (27.5%) | < 0.01* |
| 1 | 244 (36.6%) | 62 (26.9%) | 182 (41.7%) | |
| 2 | 126 (18.9%) | 46 (19.9%) | 80 (18.4%) | |
| 3 | 56 (8.4%) | 1 6 (6.9%) | 40 (9.2%) | |
| 4 | 13 (1.9%) | 2 (0.9%) | 11 (2.5%) | |
| 5 | 1 (0.1%) | 0 (0%) | 1 (0.2%) | |
| 6 | 3 (0.5%) | 1 (0.4%) | 2 (0.5%) | |
| Chronic lung disease | 1 89 (28.3%) | 69 (29.9%) | 120 (27.5%) | 0.53 |
| Diabetes mellitus | 128 (19.2%) | 44 (19.0%) | 84 (19.3%) | 1.00 |
| Dementia | 123 (18.4%) | 10 (4.3%) | 113 (25.9%) | < 0.01* |
| Cerebrovascular disease | 67 (10.0%) | 26 (11.3%) | 41 (9.4%) | 0.50 |
| Chronic heart failure | 62 (9.3%) | 7 (3.0%) | 55 (12.6%) | < 0.01* |
| Malignancy | 33 (4.9%) | 9 (3.9%) | 24 (5.5%) | 0.45 |
| Kidney disease | 29 (4.3%) | 6 (2.6%) | 23 (5.3%) | 0.12 |
| Liver disease | 15 (2.2%) | 3 (1.3%) | 12 (2.8%) | 0.28 |
| Pathogen Streptococcus pneumoniae | 126 (18.9%) | 39 (16.9%) | 87 (20.0%) | 0.35 |
| Haemophilus influenzae | 40 (6.0%) | 14 (6.1%) | 26 (6.0%) | 1.00 |
| Klebsiella pneumoniae | 30 (4.5%) | 5 (2.2%) | 25 (5.7%) | 0.04* |
| Escherichia coli | 25 (3.7%) | 3 (1.3%) | 22 (5.0%) | 0.01* |
| Pseudomonas aeruginosa | 23 (3.4%) | 10 (4.3%) | 13 (3.0%) | 0.38 |
| Moraxella catarrhalis | 16 (2.3%) | 6 (2.6%) | 10 (2.3%) | 0.78 |
| MSSA | 13 (1.9%) | 2 (0.9%) | 11 (2.5%) | 0.24 |
| MRSA | 11 (1.6%) | 2 (0.9%) | 9 (2.1%) | 0.35 |
| Serratia marcescens | 8 (1.2%) | 4 (1.7%) | 4 (0.9%) | 0.46 |
| Enterococcus faecalis | 7 (1.0% | 2 (0.9%) | 5 (1.1%) | 1.00 |
| Stenotrophomonas maltophilia | 6 (0.9%) | 2 (0.9%) | 4 (0.9%) | 1.00 |
| Legionella pneumoniae | 5 (0.7%) | 3 (1.3%) | 2 (0.5%) | 0.35 |
| Proteus merabilis | 5 (0.7%) | 1 (0.4%) | 4 (0.9%) | 0.66 |
| Enterobacter cloacae | 4 (0.6%) | 1 (0.4%) | 3 (0.7%) | 0.66 |
| Mycoplasma pneumoniae | 30 (4.5%) | 21 (9.1%) | 9 (2.1%) | < 0.01* |
| Chlamydophila pneumoniae | 22 (3.3%) | 10 (4.3%) | 12 (2.8%) | 0.36 |
CAP Community acquired pneumonia, HCAP Healthcare-associated pneumonia, PSI Pneumonia severity index, BMI Body mass index, WBC White blood cell, CRP C-reactive protein, BUN Blood urea nitrogen, MSSA Methicillin-sensitive Staphylococccusaureus, MRSA Methicillin-resistant Staphylococcus aureus Data are presented as number (%) or median (1st quartile - 3rd quartile)
P value: < 74 years vs > 75 years * Statistically significant