Introduction:
The aim of the study is to identify patient-related factors influencing the risk of early postoperative complications in Crohn’s disease (CD).

Material and methods:
A meta-analysis was conduced based on articles addressing early complications after abdominal surgery for CD. The analysis included the following risk factors: age, sex, hypoalbuminemia, serum CRP levels, anemia, blood leukocyte levels, BMI, smoking, diabetes mellitus and hypertension. A systematic review was performed between 21 November 2021 and 4 December 2021 and repeated after a three and a half years. Outcomes were reported as two effect sizes: odds ratio (OR) w and response ratio (R), both with 95% CI, p-value <0.05 and visualisation in a forest plot. The strength of evidence was determined based on Egger’s test p-value, sample size, and I² statistic.

Results:
The following significant risk factors of early postoperative complications in CD were identified assuming Level I strength of evidence: hypoalbuminemia (OR= 1.82; 95%CI 1.62-2.06), anemia (OR= 1.77; 95% CI 1.47-2.15), age≥40 years (OR= 1.44; 95%CI 1.18-1.77), diabetes (OR=1.28; 95%CI 1.04-1.57), hypertension (OR=1.27; 95% CI 1.06-1.51), smoking (OR=1.23; 95% CI 1.14-1.33). At Level II, included CRP levels (R= 1.58; 95% CI 1.32-1.89), male sex (OR=1.23; 95% CI 1.11-1.37), blood leukocyte levels (R=1.11; 95% CI 1.07-1.15).

Conclusions:
These findings suggest that nutritional status, age, comorbidities, and parameters of blood morphology and biochemistry should be carefully considered when assessing the risk of postoperative complications in patients with CD.