Patient characteristics
A total of 602 CRC patients were included in the study. After random division, 401 patients (anxiety rate = 36.2, depression rate = 35.7%) were in the development set and 201 patients (anxiety rate = 41.3%, depression rate = 36.8%) were in the validation set. No significant difference could be found in age (P = 0.604), gender (P = 0.403), marital status (P = 0.662), income (P = 0.467), education (P = 0.534), TNM stage (P = 0.294) and ECOG score (P = 0.922) between the two sets (Table 1).
Table 1
Characteristics of patients in the development and validation sets
Variable
|
Development set
|
Validation set
|
P
|
Gender
|
|
|
|
Male
|
212 (52.9)
|
99 (49.3)
|
0.403
|
Female
|
189 (47.1)
|
102 (50.7)
|
|
Age (years)
|
|
|
|
< 65
|
260 (64.8)
|
126 (62.7)
|
0.604
|
≥ 65
|
141 (35.2)
|
75 (37.3)
|
|
Marital status
|
|
|
|
Married
|
331 (82.5)
|
163 (81.1)
|
0.662
|
Single
|
70 (17.5)
|
38 (18.9)
|
|
Income
|
|
|
|
Satisfied
|
233 (58.1)
|
123 (61.2)
|
0.467
|
Unsatisfied
|
168 (41.9)
|
78 (38.8)
|
|
Education
|
|
|
|
Middle school or less
|
291 (72.6)
|
141 (70.1)
|
0.534
|
Higher than middle school
|
110 (27.4)
|
60 (29.9)
|
|
TNM stage
|
|
|
|
I/II
|
256 (63.8)
|
137 (68.2)
|
0.294
|
III
|
145 (36.2)
|
64 (31.8)
|
|
ECOG score
|
|
|
|
0–1
|
255 (63.6)
|
127 (63.2)
|
0.922
|
2–4
|
146 (36.4)
|
74 (36.8)
|
|
Anxiety rate
|
36.2
|
41.3
|
0.221
|
Depression rate
|
35.7
|
36.8
|
0.781
|
HADS
|
|
|
|
Anxiety a
|
6.71 ± 4.38
|
6.67 ± 4.26
|
0.917
|
Depression a
|
6.03 ± 4.23
|
6.14 ± 4.17
|
0.748
|
a Mean ± SD |
Risk factors related to postoperative anxiety in the development set
Univariate analysis revealed the association between each factor and postoperative anxiety, including age (P = 0.516), gender (P = 0.027), marital status (P = 0.000), income (P = 0.024), education (P = 0.857), TNM stage (P = 0.000) and ECOG score (P = 0.004). Multivariate analysis indicated that gender (OR = 2.176, 95%CI = 1.367–3.463 for female, P = 0.001; using male as the reference), marital status (OR = 3.302, 95%CI = 1.854–5.880 for single, P = 0.000, using married as the reference), income (OR = 1.782, 95%CI = 1.116–2.844 for single, P = 0.016 for unsatisfied, using satisfied as the reference), TNM stage (OR = 2.131, 95%CI = 1.351–3.362 for stage III, P = 0.001, using stage I/II as the reference) and ECOG score (OR = 2.493, 95%CI = 1.548–4.013 for 2–4 points, P = 0.000, using 0–1 point as the reference) were the statistically significant predictors related to postoperative anxiety (Table 2).
Table 2
Logistic regression analysis for postoperative anxiety in the development set
Variable
|
Univariate analyses
|
Multivariate analyses
|
HR [95%CI]
|
P
|
HR [95%CI]
|
P
|
Gender
|
|
|
|
|
Male
|
1
|
|
1
|
|
Female
|
1.589 [1.054–2.394]
|
0.027
|
2.176 [1.367–3.463]
|
0.001
|
Age (years)
|
|
|
|
|
< 65
|
1
|
|
|
|
≥ 65
|
0.867 [0.564–1.333]
|
0.516
|
|
|
Marital status
|
|
|
|
|
Married
|
1
|
|
1
|
|
Single
|
2.870 [1.694–4.861]
|
0.000
|
3.302 [1.854–5.880]
|
0.000
|
Income
|
|
|
|
|
Satisfied
|
1
|
|
1
|
|
Unsatisfied
|
1.625 [1.066–2.476]
|
0.024
|
1.782 [1.116–2.844]
|
0.016
|
Education
|
|
|
|
|
Middle school or less
|
1
|
|
|
|
Higher than middle school
|
0.959 [0.607–1.515]
|
0.857
|
|
|
TNM stage
|
|
|
|
|
I/II
|
1
|
|
1
|
|
III
|
2.150 [1.410–3.279]
|
0.000
|
2.131 [1.351–3.362]
|
0.001
|
ECOG score
|
|
|
|
|
0–1
|
1
|
|
1
|
|
2–4
|
1.872 [1.229–2.851]
|
0.004
|
2.493 [1.548–4.013]
|
0.000
|
Risk factors related to postoperative depression in the development set
Similarly, univariate analysis revealed the association between each factor and postoperative depression, including age (P = 0.350), gender (P = 0.002), marital status (P = 0.000), income (P = 0.037), education (P = 0.857), TNM stage (P = 0.004) and ECOG score (P = 0.002). Multivariate analysis indicated that gender (OR = 2.667, 95%CI = 1.665–4.273 for female, P = 0.000; using male as the reference), marital status (OR = 3.40, 95%CI = 1.900-6.085 for single, P = 0.000, using married as the reference), income (OR = 1.671, 95%CI = 1.045–2.672 for single, P = 0.032 for unsatisfied, using satisfied as the reference), TNM stage (OR = 1.854, 95%CI = 1.171–2.935 for stage III, P = 0.008, using stage I/II as the reference) and ECOG score (OR = 2.702, 95%CI = 1.671–4.369 for 2–4 points, P = 0.000, using 0–1 point as the reference) were independent indicators for postoperative depression (Table 3).
Table 3
Logistic regression analysis for postoperative depression in the development set
Variable
|
Univariate analyses
|
Multivariate analyses
|
HR [95%CI]
|
P
|
HR [95%CI]
|
P
|
Gender
|
|
|
|
|
Male
|
1
|
|
1
|
|
Female
|
1.897 [1.254–2.869]
|
0.002
|
2.667 [1.665–4.273]
|
0.000
|
Age (years)
|
|
|
|
|
< 65
|
1
|
|
|
|
≥ 65
|
0.814 [0.528–1.254]
|
0.350
|
|
|
Marital status
|
|
|
|
|
Married
|
1
|
|
1
|
|
Single
|
2.746 [1.623–4.645]
|
0.000
|
3.400 [1.900-6.085]
|
0.000
|
Income
|
|
|
|
|
Satisfied
|
1
|
|
1
|
|
Unsatisfied
|
1.568 [1.028–2.391]
|
0.037
|
1.671 [1.045–2.672]
|
0.032
|
Education
|
|
|
|
|
Middle school or less
|
1
|
|
|
|
Higher than middle school
|
1.043 [0.661–1.647]
|
0.857
|
|
|
TNM stage
|
|
|
|
|
I/II
|
1
|
|
1
|
|
III
|
1.854 [1.216–2.827]
|
0.004
|
1.854 [1.171–2.935]
|
0.008
|
ECOG score
|
|
|
|
|
0–1
|
1
|
|
1
|
|
2–4
|
1.942 [1.273–2.962]
|
0.002
|
2.702 [1.671–4.369]
|
0.000
|
Nomogram for postoperative anxiety and depression
Subsequently, gender, marital status, income, TNM stage and ECOG score were used to construct the risk nomogram for postoperative anxiety (Fig. 1A) and depression (Fig. 1B).
In terms of nomogram for postoperative anxiety, the AUCs of the development and validation sets were 0.696 (95%CI = 0.640–0.751) and 0.677 (95%CI = 0.598–0.756), respectively (Fig. 2A). The calibration curves also demonstrated good consistencies between predicted and observed anxiety rates in development and validation sets (Fig. 3A). Additionally, DCA also indicated that the proposed nomogram owned excellent net benefits in guiding clinical decision in both sets (Fig. 4A).
Regarding to nomogram for postoperative depression, the AUCs of the development and validation sets were 0.710 (95%CI = 0.655–0.765) and 0.699 (95%CI = 0.621–0.777), respectively (Fig. 2B). Moreover, the same as the nomogram for postoperative anxiety, the calibration curves (Fig. 3B) and DCA (Fig. 4B) also presented satisfy results in both development and validation sets.