Table 1.
Preoperative characteristics before and after propensity score matching.
| Characteristics | Entire cohort | SMD | |
|---|---|---|---|
| GCG (n = 32) | HCG (n = 44) | ||
| Age, median [year (IQR)] | 70.0 (60.3–73.0) | 64.0 (61.0–68.8) | 0.21 |
| Sex, Males (%)/Females (%) | 27 (84.4)/5 (15.6) | 31 (70.5)/13 (29.5) | 0.16 |
| BMI, median [kg/m2 (IQR)] | 23.1 (20.6–25.5) | 21.6 (19.9–23.2) | 0.23 |
| Preoperative RSST score | 5.0 (4.0–6.8) | 4.0 (3.3–5.0) | 0.43 |
| Preoperative tongue pressure [kpa (IQR)] | 34.9 (30.5–40.3) | 35.4 (29.9–41.3) | 0.03 |
| Neoadjuvant chemotherapy ( +) | 23 (71.9) | 28 (63.6) | 0.09 |
|
Clinical stage (8th UICC) 0, I, II (%)/III, IV (%) |
18 (56.3)/14 (43.8) | 31 (70.5)/13 (29.5) | 0.15 |
| Histological diagnosis | 0.28 | ||
| SCC (%)/adenocarcinoma (%)/others (%) | 26 (81.3)/4 (12.5)/ 2 (6.3) | 43 (97.7)/0 (0.0)/ 1 (2.3) | |
| Smoking status | 0.24 | ||
| Never (%)/Past (%)/Current (%) | 3 (9.4)/26 (81.3)/3(9.4) | 6 (13.6)/38 (86.4)/0 (0.0) | |
| Quantity and frequency of drinking (/week) | 0.55 | ||
| Never (%)/Light (%)/Moderate (%)/Heavy (%) | 8 (25.0)/4 (12.5)/12 (37.5)/8 (25.0) | 5 (11.4)/1 (2.3)/38 (86.4)/0 (0.0) | |
| Preoperative WBC count [103/µL (IQR)] | 5.25 (4.45–6.49) | 4.86 (4.08–5.47) | 0.20 |
| Preoperative CRP concentration [mg/dL (IQR)] | 0.12 (0.05–0.19) | 0.12 (0.05–0.21) | − 0.01 |
| Preoperative albumin concentration [g/dL (IQR)] | 3.9 (3.6–4.0) | 3.9 (3.6–4.2) | − 0.10 |
| Characteristics | Propensity score-matched cohort | SMD | |
|---|---|---|---|
| GCG (n = 25) | HCG (n = 25) | ||
| Age, median [year (IQR)] | 70.0 (61.5–73.0) | 64.0 (60.5–69.5) | 0.19 |
| Sex, Males (%)/Females (%) | 21 (84.0)/4 (16.0) | 20 (80.0)/5 (20.0) | 0.05 |
| BMI, median [kg/m2 (IQR)] | 23.0 (20.6–25.4) | 21.5 (19.5–23.4) | 0.22 |
| Preoperative RSST score | 5.0 (4.0–6.0) | 4.0 (4.0–5.0) | 0.24 |
| Preoperative tongue pressure [kpa (IQR)] | 35.0 (30.7–41.4) | 38.2 (30.4–43.8) | −0.05 |
| Neoadjuvant chemotherapy ( +) | 19 (76.0) | 15 (60.0) | 0.18 |
| Clinical stage (8th UICC) | 0.31 | ||
| 0, I, II (%)/III, IV (%) | 14 (56.0)/11 (44.0) | 21 (84.0)/4 (16.0) | |
| Histological diagnosis | 0.33 | ||
| SCC (%)/adenocarcinoma (%)/others (%) | 20 (80.0)/3 (12.0)/2(8.0) | 25 (100)/0 (0.0) /0 (0.0) | |
| Smoking status | 0.08 | ||
| Never (%)/Past (%)/Current (%) | 2 (8.0)/20 (80.0)/3 (12.0) | 3 (12.0)/22 (88.0)/0 (0.0) | |
| Quantity and frequency of drinking (/week) | 0.13 | ||
| Never (%)/Light (%)/Moderate (%)/Heavy (%) | 7 (28.0)/3 (12.0)/11 (44.0)/4(16.0) | 4 (16.0)/1 (4.0)/20 (80.0)/0 (0.0) | |
| Preoperative WBC count [103/µL (IQR)] | 5.64 (4.52–6.69) | 4.87 (4.18–5.32) | 0.24 |
| Preoperative CRP concentration [mg/dL (IQR)] | 0.12 (0.05–0.19) | 0.12 (0.04–0.29) | 0.02 |
| Preoperative albumin concentration [g/dL (IQR)] | 3.9 (3.7–4.0) | 4.0 (3.7–4.2) | −0.12 |
GCG gum-chewing group, HCG historical control group, IQR interquartile range, BMI body mass index, RSST repetitive saliva swallowing test, UICC Union for International Cancer Control, SCC squamous cell carcinoma, WBC white blood cell, CRP C-reactive protein, SMD standardized mean difference.