General information
Among 510 patients with IBD, CD accounted for 23.9%, UC accounted for 61.8%, and IBDU accounted for 14.3%, which showed an overall upward trend. In the past 9 years, the number of inpatients with IBD increased by 3.84 times, CD increased by 14.5 times, UC increased by 1.4 times, IBDU increased by 7.7 times, and the number of newly added patients increased by 3 times. The specific growth trend was shown in Fig. 1. The peak incidence of CD and UC was between 21-30 years old, while IBDU has double peaks between 21-30 years old and 41-50 years old. The specific age of onset and the distribution of male and female are shown in Fig. 2.
The incidence of severe complications of hospitalized IBD patients was 39.02% (199 cases), among which 71.9% (143 cases) had one severe complication, 19.1% (38 cases) had two severe complications, and 9.0% (18 cases) had three or more severe complications. The incidence of severe complications of CD was 71.31% (87 cases), 23.81% (75 cases) for UC, and 50.68% (37 cases) for IBDU. The differences between CD and UC, CD and IBDU, UC and IBDU in the incidence of severe complications were statistically significant (P <0.005).
The course of IBD patients ranged from 0 to 41 years, with an average duration of 6.4 ± 6.6 years, 419 patients with the course of 0-10 years, and 91 patients with the course of >10 years. The course of CD patients ranged from 0 to 41 years, with an average duration of 4.6 ± 3.1 years, 99 patients with the course of 0-10 years, and 23 patients with the course of >10 years. The course of UC patients ranged from 0 to 33 years, with an average duration of 6.4 ± 6.7 years, 256 patients with the course of 0-10 years, and 59 patients with the course of >10 years. The course of IBDU patients ranged from 0 to 33 years, with an average duration of 4.9 ± 5.8 years, 64 patients with the course of 0-10 years, and 9 patients with the course of >10 years.
Gender factors
Among the 87 CD patients with severe complications, 60 were male and 27 were female, with a male-female ratio of 2.2:1. Among the 75 UC patients with severe complications, 47 were male and 28 were female, with a male-female ratio of 1.7:1. Among the 37 IBDU patients with severe complications, 24 were male and 13 were female, with a male-female ratio of 1.9:1. The gender difference in the incidence of severe complications among the three groups were not statistically significant ( P >0.05), as shown in Table 1. However, among the 34 patients with gastrointestinal fistula, 28 were male and 6 were female, the gender difference in the incidence rate was statistically significant (c2=5.165, P=0.023), as detailed in Table 1.
The factor of disease course
The cumulative incidence of severe complications was 36.99% (155 cases) in IBD patients with the course of 0-10 years, and 48.35% (44 cases) with the course of >10 years, the difference between them was statistically significant (c2=4.054, P=0.044). The cumulative incidence of severe complications was 67.68% (67 cases) in CD patients with the course of 0-10 years, and 86.96% (20 cases) with the course of >10 years, the difference between them was not statistically significant (c2=3.391, P=0.066). The cumulative incidence of severe complications was 22.66% (58 cases) in UC patients with the course of 0-10 years, and 28.81% (17 cases) with the course of >10 years, the difference between them was not statistically significant (c2=1.002, P=0.317). The cumulative incidence of severe complications was 46.88% (30 cases) in IBDU patients with the course of 0-10 years, and 77.78% (7 cases) with the course of >10 years, the difference between them was not statistically significant (c2=3.015, P=0.083). The details are reported in Table 2.
The factor of onset age
In CD, 12 patients were diagnosed with ≤ 16 years old, the incidence of severe complications was 66.67% (8 cases). 72 patients were diagnosed with 17-40 years old, the incidence of severe complications was 65.28% (47 cases). 38 patients were diagnosed with >40 years old, the incidence of severe complications was 84.21% (32 cases), the incidence differences between three onset age groups were not statistically significant (c2=4.498, P=0.106). However, it is worth mentioning that P=0.036 ( but, P>0.05/3) when comparing the incidence of severe complications between group of 17-40 years old and >40 years old, the specific trend is shown in Fig. 3. In UC, 16 patients were diagnosed with <20 years old, the incidence of severe complications was 25.00% (4 cases). 221 patients were diagnosed with 20-49 years old, the incidence of severe complications was 19.00% (42 cases). 78 patients were diagnosed with ≥50 years old, the incidence of severe complications was 37.18% (29 cases). The incidence differences between three onset age groups were statistically significant (c2=10.511, P=0.005), and there was a significant difference between group of 20-49 years old and ≥50 years old (P=0.001, P<0.05/3), the specific trend is shown in Fig. 3. In IBDU, 10 patients were diagnosed with <20 years old, the incidence of severe complications was 70.00% (7 cases). 45 patients were diagnosed with 20-49 years old, the incidence of severe complications was 46.67% (21 cases). 18 patients were diagnosed with ≥50 years old, the incidence of severe complications was 50.00% (9 cases). The incidence differences between three onset age groups were not statistically significant (c2=1.787, P=0.409), the specific trend is shown in Fig. 3.
Nine severe complications
13 patients with digestive tract perforation: the incidence of digestive tract perforation in CD patients was 6.56% (8 cases), UC was 0.32% (1 case), IBDU was 5.48% (4 cases), and the difference in the incidence between CD and UC, IBDU and UC was statistically significant (P <0.001). 13 patients with massive digestive tract hemorrhage: the incidence of massive digestive tract hemorrhage in CD patients was 5.36% (6 cases), UC was 1.59% (5 cases), IBDU was 2.74% (2 cases), and the difference in the incidence between CD and UC was statistically significant (P=0.046). 7 patients with thrombosis: the incidence of thrombosis in CD patients was 0.82% (1 case), UC was 1.27% (4 cases), IBDU was 2.74% (2 cases), and there was no statistically significant difference in the incidence between the three groups (P>0.05). 6 patients with toxic megacolon: the incidence of toxic megacolon in UC patients was 1.58% (5 cases), IBDU was 1.37% (1 case), and the difference in the incidence between two groups was not statistically significant (P>0.05). 34 patients with digestive tract fistula: the incidence of digestive tract fistula in CD patients was 13.93% (17 cases), UC was 3.81% (12 cases), IBDU was 6.85% (5 cases). There was a statistically significant difference in the incidence between CD and UC groups (P< 0.001). 118 patients with digestive tract stenosis: the incidence of digestive tract stenosis in CD patients was 59.02% (72 cases), UC was 6.67% (21 cases), IBDU was 34.25% (25 cases), and the incidence differences between CD and UC, CD and IBDU, UC and IBDU were statistically significant (P< 0.001). 39 patients with severe malnutrition: the incidence of severe malnutrition in CD patients was 11.48% (14 cases), UC was 6.35% (20 cases), IBDU was 6.85% (5 cases), and there were no statistical differences in incidence between the three groups (P> 0.05). 41 patients with severe infection: the incidence of severe infection in CD patients was 10.66% (13 cases), UC was 6.98% (22 cases), IBDU was 8.22% (6 cases), and there were no significant differences in the incidence between the three groups (P> 0.05). 11 patients with carcinogenesis: the incidence of Carcinogenesis in CD patients was 1.64% (2 cases) , UC was 2.86% (9 cases), and the difference in the incidence between CD and UC was not statistically significant (P> 0.05). The detailed situation is shown in Table 3.
According to the time when severe complications occurred: in the course of 0-10 years, severe complications of CD patients were most common in digestive tract stenosis (65 cases), UC were severe infection (20 cases), and IBDU were digestive tract stenosis (23 cases). In the course of >10 years, severe complications of CD patients were most common in digestive tract stenosis (7 cases), UC were carcinogenesis (5 cases), IBDU were digestive tract stenosis (2 cases). The incidence and distribution of severe complications are shown in Table 4. Between the two groups, the incidence differences of CD patients in digestive tract and digestive tract stenosis were statistically significant (P<0.05), and the incidence difference of UC patients in carcinogenesis was statistically significant (P<0.01), as detailed in Table 5.
In CD patients, the incidence of nine severe complications were no statistically significant difference among different onset age groups (P >0.05). In UC patients, the incidence of toxic megacolon were statistically significant difference among different onset age groups (c2=6.597, P=0.037), and the difference was significant when compared the group of age <20 years old and 20-49 years old (P=0.014, P<0.05/3). The incidence of severe malnutrition were statistically significant difference among different onset age groups (c2=14.752, P<0.001), and the difference was significant when compared the group of age 20-49 years old and ≥50 years old (P<0.001, P<0.05/3). In IBDU patients, the incidence of nine severe complications were no statistically significant difference among different onset age groups (P>0.05). The incidence and distribution of nine severe complications in IBD patients is shown in Table 6.
Prognosis
53 hospitalized IBD patients (10.39%) received surgical treatment in our center, including 48 patients received one operation, 3 patients received two operations (both CD), and 2 patients received three operations (1 CD and 1 IBDU). The surgical rate of CD patients was 27.87% (34 cases), UC was 5.08% (16 cases), IBDU was 4.11% (3 cases), the surgical rates of IBD patients were shown in Fig. 4, and the differences of operative rate between CD and UC, CD and IBDU were statistically significant (c2=45.075, P< 0.001). The surgical rate of IBD patients in the course of 0-10 years was 11.22% (47 cases), CD was 31.31% (31 cases), UC was 5.08% (13 cases), IBDU was 4.69% (3 cases). In the course of >10 years, the surgical rate of IBD patients was 6.59% (6 cases), CD was 13.04% (3 cases), UC was 5.08% (3 cases). There were no statistically significant differences in the surgical rate between IBD, CD, UC and IBDU patients at different courses (P>0.05), as detailed in Table 7. The mortality of IBD patients was 1.57% (8 cases), including 4 cases of CD and 4 cases of UC, and there was no statistically significant difference in mortality between the two groups (P>0.05), the mortalities of IBD patients were shown in Fig. 4. The causes of death included: postoperative complications (4 cases), toxic megacolon (2 cases), digestive tract perforation (1 case), and colonic malignant tumor metastasis (1 case).