Objective To investigate the incidence and influencing factors of parastomal hernia in patients with permanent colostomy.

Methods The retrospective cohort study was conduc-ted. The clinicopathological data of 72 patients with permanent colostomy in the Beijing Friendship Hospital of Capital Medical University from January 2016 to June 2020 were collected. There were 50 males and 22 females, aged (66±12)years. Observations indicators: (1) follow‑up; (2) analysis of factors affecting the incidence of parastomal hernia; (3) comparison of the incidence of parastomal hernia in patients with different age. Follow‑up was conducted using outpatient examination. Patients were followed up once every 12 months after surgery to detect the incidence of parastomal hernia up to September 2021. Measurement data with normal distribution were represented as Mean±SD, and comparison between groups was conducted using the t test. Measurement data with skewed distribution were represented as M(range). Count data were expressed as absolute numbers and percentages, and comparison between groups was conducted using the chi-square test. Univariate analysis was conducted using the corresponding statistical methods based on data type. Multivariate analysis was conducted using the Logistic regression model. Kaplan‑Meier method was used to draw the parastomal hernia occurrence curve and calculate the incidence rate of parastomal hernia and Log‑rank test was used to analyze the incidence of parastomal hernia.

Results (1) Follow‑up. All 72 patients were followed up for 23(range, 12‒76)months. During the follow‑up, there were 31 patients developed parastomal hernia, with the incidence as 20.8%(15/72), 36.1%(26/72) and 43.1%(31/72) at postoperative 1 year, postoperative 2 year and postoperative 5 year, respectively. Of the 31 patients with parastomal hernia, there were 21 cases of type Ⅰ, 3 cases of type Ⅱ and 7 cases of type Ⅲ. Patients with parastomal hernia recovered with conservative treatment. (2) Analysis of factors affecting the incidence of parastomal hernia. Results of univariate analysis showed that age, subcutaneous fat thickness and rectus abdominis thickness were related factors affecting the incidence of parastomal hernia (χ²=7.98, t=‒2.95, 2.02, P<0.05). Results of multivariate analysis showed that age, subcutaneous fat thickness and rectus abdominis thickness were independent factors affecting the incidence of parastomal hernia (odds ratio=4.07, 3.19, 0.07, 95% confidence interval as 1.46‒11.32, 1.43‒7.09, 0.01‒0.84, P<0.05). (3) Comparison of the incidence of parastomal hernia in patients with different age. Of the 72 patients, there were 37 cases with age <65 years and 35 cases with age >65 years. Of the 31 patients with parastomal hernia, there were 10 cases with age<65 years and all of them with type Ⅰ parastomal hernia, and the incidence of parastomal hernia in postoperative 1 year and postoperative 2 year was 13.5%(5/37) and 27.0%(10/37), respectively. There were 21 cases with age ≥65 years and cases with type Ⅰ, type Ⅱ and type Ⅲ parastomal hernia were 11, 3 and 7, respectively. The postoperative 1 year and postoperative 2 year incidence of parastomal hernia in the 21 cases was 28.6%(10/35) and 45.7%(16/35), respectively. There was a significant difference in the incidence of parastomal hernia between patients<65 years and ≥65 years (χ²=9.28, P<0.05).

Conclusion Age, subcutaneous fat thickness and rectus abdominis thickness are independent factors affecting the incidence of parastomal hernia.