TABLE 1.
Clinical characteristics of the participants with and without postoperative delirium.
| Variables | With postoperative delirium | Without postoperative delirium | P-value |
| (N = 44) | (N = 99) | ||
| Demographic variables | |||
| Sex, Female, n (%) | 29 (66) | 70 (71) | 0.566 |
| Male, n (%) | 15 (34) | 29 (29) | |
| Age, median (IQR, 25th–75th), yr. | 71 (68–79) | 70 (66–75) | 0.387 |
| Education, median (IQR, 25th–75th), yr. | 9 (5–12) | 9 (6–12) | 0.660 |
| CCI, n (%) | |||
| 2 | 10 (23) | 26 (26) | 0.330 |
| 3 | 11 (25) | 36 (36) | |
| 4 | 15 (34) | 21 (21) | |
| ≥ 5 | 8 (18) | 16 (16) | |
| BMI, mean ± S.D., kg/m2 | 26.15 ± 4.10 | 25.92 ± 3.37 | 0.741 |
| Type of surgery, n (%) Keen surgery |
36 (81) | 90 (91) | 0.161 |
| Hip surgery | 8 (19) | 9 (9) | |
| ASA, n (%) | |||
| I | 1 (2) | 5 (5) | 0.194 |
| II | 31 (71) | 79 (80) | |
| III | 12 (27) | 15 (15) | |
| Length of anesthesia, mean ± S.D., minutes | 134 ± 40 | 131 ± 51 | 0.773 |
| Length of surgery, mean ± S.D., minutes | 102 ± 33 | 91 ± 30 | 0.042 |
| Preoperative MMSE, median (IQR), scores | 26 (23–27) | 26 (24–28) | 0.094 |
| Peak CAM-S scores, median (IQR), scores | 6 (5–7) | 3 (2–4) | < 0.001 |
| Preoperative VAS Scores, median (IQR) | 8.0 (6.0–9.0) | 6.0 (5.0–8.0) | 0.027 |
| Postoperative day 1 VAS Scores, median (IQR) | 7.5 (6.0–8.0) | 6.0 (4.0–8.0) | 0.055 |
| Postoperative day 2 VAS Scores, median (IQR) | 6.0 (6.0–8.0) | 6.0 (4.0–8.0) | 0.017 |
| Postoperative day 3 VAS Scores, median (IQR) | 6.0 (5.0–8.0) | 5.0 (4.0–7.0) | 0.064 |
| Plasma variables | |||
| Preoperative homocysteine, (IQR, 25th–75th) (mmol/L) | 15.43 (12.23, 21.26) | 12.51 (10.42, 16.32) | 0.036 |
| Postoperative CRP, median (IQR, 25th–75th), (mg/L) | 61.60 (40.48, 106.31) | 46.50 (27.60, 78.20) | < 0.001 |
ASA, American Society of Anesthesiologists; BMI, Body-Mass-Index; CCI, Charlson comorbidity index; CAM-S, Confusion Assessment Method—Severity; CRP, C-Reactive Protein; MMSE, Mini-Mental State Examination; VAS, Visual Analog Scale. Normally distributed continuous variables were presented as Mean ± standard deviation (S.D.). An Independent t-test evaluated the difference; non-normally distributed continuous variables were presented in the median and interquartile range (25th to 75th percentile). The difference was assessed by Mann–Whitney test. The Chi-square test or Fisher’s exact test was used to determine the difference in the categorical variables.