Table 1.
Baseline variables
| Variables | All patients (n = 915) |
Control group (n = 425) |
Malnutrition group (n = 490) | P |
|---|---|---|---|---|
| Age, year, mean ± SD | 71.6 ± 5.2 | 69.3 ± 4.2 | 73.6 ± 5.2 | < 0.001 |
| ≥75 years, n (%) | 264 (28.9 %) | 61(14.4 %) | 203(41.1 %) | < 0.001 |
| Male, n (%) | 548 (59.9 %) | 180(44.0 %) | 310(56.0 %) | 0.025 |
| BMI, kg/m2, mean ± SD | 24.2 ± 3.5 | 25.2 ± 3.0 | 23.2 ± 3.6 | < 0.001 |
| Preoperative comorbidity, n (%) | ||||
| Stroke | 52 (5.7 %) | 14(3.3 %) | 38(7.8 %) | 0.004 |
| Hypertension | 475 (51.9 %) | 226(53.2 %) | 249(50.8 %) | 0.476 |
| Coronary heart disease | 129 (14.1 %) | 61(14.4 %) | 68(13.9 %) | 0.837 |
| Arrhythmia | 57 (6.2 %) | 26(6.1 %) | 31(6.3 %) | 0.896 |
| Pulmonary disease a | 66 (7.2 %) | 27(6.4 %) | 39(8.0 %) | 0.349 |
| Diabetes | 219 (23.9 %) | 108(25.4 %) | 111(22.7 %) | 0.329 |
| Hyperlipidemia | 95 (10.4 %) | 49(11.5 %) | 46(9.4 %) | 0.290 |
| Hepatic dysfunction b | 45 (4.9 %) | 14(3.3 %) | 31(6.3 %) | 0.034 |
| Malignant tumor c | 105 (11.5 %) | 37(8.7 %) | 68(13.9 %) | 0.014 |
| Chronic smoking d | 223 (24.4 %) | 105(24.7 %) | 118(24.1 %) | 0.826 |
| Cognitive impairment e | 597 (65.2 %) | 260(61.2 %) | 337(68.8 %) | 0.016 |
| History of surgery, n (%) | 491(53.7 %) | 221(52.0 %) | 270(55.1 %) | 0.881 |
| CCI, median (IQR)e | 2 (2,3) | 2(2,3) | 3(2,3) | < 0.001 |
| ASA classification, n (%) | 0.001 | |||
| Class II | 678 (74.0 %) | 336(79.1 %) | 342(69.8 %) | |
| Class III | 237 (26.0 %) | 89(20.9 %) | 148(30.2 %) | |
| Laboratory tests, | ||||
| Albumin, g/L, mean ± SD | 40.6 ± 4.7 | 41.7 ± 3.3 | 39.6 ± 5.5 | < 0.001 |
| <30 g/L, n (%) | 22(2.4 %) | 0(0.0 %) | 22(4.5 %) | < 0.001 |
| Creatinine, µmol/L, mean ± SD | 80.2 ± 20.9 | 77.4 ± 18.7 | 82.5 ± 22.3 | 0.004 |
| Glucose, mmol/L, mean ± SD | 6.0 ± 1.7 | 6.0 ± 1.6 | 6.1 ± 1.8 | 0.332 |
| Hematocrit, %, mean ± SD | 39.4 ± 5.3 | 40.8 ± 4.7 | 38.2 ± 5.5 | 0.002 |
| Barthel index, median (IQR) f | 100 (100,100) | 100 (95,100) | 100 (100,100) | 0.606 |
| NRS 2002, median (IQR) | 3 (2,4) | 2 (1,2) | 3 (3,5) | < 0.001 |
SD standard deviation, BMI body mass index, CCI Charlson Comorbidity Index, IQR interquartile range, ASA American Society of Anesthesiology, NRS 2002 nutritional risk screening 2002
a Pulmonary disease included chronic obstructive pulmonary disease and asthma
b Hepatic dysfunction was defined as Alanine transaminase and/or aspartate transaminase higher than 5 times of the upper normal limit
c Malignant tumor was defined as carcinoma (carcinoma, squamous cell carcinoma and adenocarcinoma), sarcoma and undifferentiated carcinoma
d Chronic smoking was defined as half a pack of cigarettes per day for at least 2 years
e Cognitive impairment was defined as Mini-Mental State Examination (MMSE) score less than 27
f Barthel index was used to assess activity of daily life (0-100 score, and higher score indicates better activity)