Table 1. Patient demographics and preoperative factors.
| Variable | Overall (n = 570) | Delirium (n = 38) | Non-delirium (n = 532) | P value |
|---|---|---|---|---|
| Median age, years (range) | 70 (35–88) | 75.5 (62–88) | 70 (35–88) | <0.001† |
| Male sex, n (%) | 369 (64.7) | 32 (84.2) | 337 (63.4) | 0.009†† |
| Body mass index, n (%) | 0.22†† | |||
| <18.5 | 41 (7.2) | 5 (13.2) | 36 (6.8) | |
| 18.5–24.9 | 396 (69.5) | 27 (71.1) | 369 (69.4) | |
| >25 | 133 (23.3) | 6 (15.7) | 127 (23.8) | |
| Brinkman index (range) | 750 (0–4000) | 900 (0–3600) | 700 (0–4000) | 0.008† |
| Pathological stage, n (%) | 0.67†† | |||
| 0–I | 378 (66.3) | 24 (63.2) | 354 (66.5) | |
| II–IV | 192 (33.7) | 14 (36.8) | 178 (33.5) | |
| Histologic structure, n (%) | <0.001†† | |||
| Adenocarcinoma | 356 (62.4) | 13 (34.2) | 343 (64.5) | |
| Squamous cell carcinoma | 160 (28.1) | 21 (55.3) | 139 (26.1) | |
| Others | 54 (9.5) | 4 (10.5) | 50 (9.4) | |
| ASA-PS, n (%) | <0.001††† | |||
| 1, 2 | 506 (88.8) | 26 (68.4) | 480 (90.2) | |
| 3+ | 64 (11.2) | 12 (31.6) | 52 (9.8) | |
| Preoperative comorbidity, n (%) | ||||
| Hypertension | 160 (28.1) | 10 (26.3) | 150 (28.2) | 0.80†† |
| Diabetes mellitus | 66 (11.6) | 7 (18.4) | 59 (11.1) | 0.19††† |
| Cardiovascular disease | 65 (11.4) | 9 (23.7) | 56 (10.5) | 0.03††† |
| Cerebrovascular disease | 30 (5.2) | 8 (21.1) | 22 (4.1) | <0.001††† |
| Psychiatric disorder | 7 (1.23) | 1 (2.6) | 6 (0.88) | 0.39††† |
| Dementia | 6 (1.05) | 3 (7.89) | 3 (0.56) | 0.005††† |
| Alcohol abuse | 1 (0.18) | 1 (2.6) | 0 (0.00) | 0.07††† |
| Other malignancy | 135 (23.7) | 11 (28.9) | 124 (23.3) | 0.43†† |
| Pulmonary emphysematous change | 257 (45.2) | 25 (65.8) | 232 (43.7) | 0.008†† |
| Preoperative blood measurements (range) | ||||
| Total protein (g/dl) | 7.1 (5.2–9.9) | 7.1 (5.2–8.6) | 7.1 (5.2–9.9) | 0.76† |
| Albumin (g/dl) | 4.2 (0.4–5.3) | 3.8 (0.4–4.9) | 4.2 (2.1–5.3) | <0.001† |
| Lymphocytes (103/μl) | 1.6 (0.4–6.5) | 1.6 (0.9–3.7) | 1.6 (0.4–6.5) | 0.35† |
| Median PNI (range) | 49.5 (4.5–77.5) | 47.5 (8.5–61.5) | 49.5 (4.5–77.5) | 0.69† |
| Sodium (mEq/l) | 140 (122–148) | 140 (131–143) | 140 (122–148) | 0.66† |
| Potassium (mEq/l) | 4.3 (3.0–5.5) | 4.2 (3.6–5.4) | 4.3 (3.0–5.5) | 0.66† |
| Glucose (mg/dl) | 102 (57–318) | 107 (71–241) | 101 (57–318) | 0.13† |
| Hemoglobin (g/dl) | 13.2 (8.4–16.9) | 13.1 (9.9–16.9) | 13.2 (8.4–16.9) | 0.34† |
| MCV (fL) | 95 (41.8–113.8) | 97.3 (85–113.8) | 94.9 (41.8–113.6) | 0.002† |
| CRP (mg/dl) | 0.09 (0–23.27) | 0.125 (0–7.91) | 0.09 (0–23.27) | 0.04† |
| Preoperative pukmonary function test (range) | ||||
| %VC (%) | 105.3 (45.6–162.9) | 96.5 (59.0–131.7) | 105.6 (45.6–162.9) | 0.02† |
| %FEV1 (%) | 102.3 (38.8–200.9) | 102.4 (58.3–186.0) | 102.3 (38.8–200.9) | 0.66† |
| FEV1% | 75.0 (40.8–100.0) | 73.1 (49.5–92.5) | 75.1 (40.8–100.0) | 0.29† |
%VC, percent vital capacity; %FEV1, percent forced expiratory volume in 1 s; FEV1%
ASA-PS, American Society of Anesthesiologists physical status; CRP, C-reactive protein; MCV, mean corpuscular volume; PNI, prognostic nutritional index; FEV1%, forced expiratory volume in 1 s
†, Mann–Whitney U-test
††, Pearson's chi-squared test
†††, Fisher's exact test