Assessment of potential influencing factors on the outcome in small (< 2 cm) umbilical hernia repair: a registry-based multivariable analysis of 31,965 patients.

INTRODUCTION: How best to treat a small (< 2 cm) umbilical hernia continues to be the subject of controversial debate. The recently published guidelines for treatment of umbilical hernias from the European Hernia Society and Americas Hernia Society recommend open mesh repair for defects ≥ 1 cm. Since the quality of evidence is limited for hernias with defect sizes smaller than 1 cm, suture repair can be considered. To date, little is known about the potential influencing factors on the outcome in small (< 2 cm) umbilical hernia repair. This multivariable analysis of data from the Herniamed Registry now aims to assess these factors. METHODS: The data of patients with primary elective umbilical hernia repair and defect size < 2 cm entered into the Herniamed Registry from September 1, 2009 to December 31, 2018 were analyzed to assess through multivariable analysis all confirmatory pre-defined potential influencing factors on the primary outcome criteria intraoperative and postoperative complications, general complications, complication-related reoperations, recurrence rate and rates of pain at rest, pain on exertion and chronic pain requiring treatment at 1-year follow-up. RESULTS: 31,965 patients (60%) met the inclusion criteria. The proportion of suture repairs was 78.6% (n = 25,119), of open mesh repairs 15.2% (n = 4853), and of laparoscopic mesh repairs 6.2% (n = 1993). Compared with open mesh repair, suture repair had a highly significantly unfavorable association with the recurrence rate (OR = 1.956 [1.463; 2.614]; p < 0.001). Female gender also had an unfavorable relation to the recurrence rate (OR = 1.644 [1.385; 1.952]; p < 0.001). Compared with open mesh repair, open suture repair had a highly significantly favorable association with the rate of postoperative complications (OR = 0.583 [0.484; 0.702]; p < 0.001) and complication-related reoperations (OR = 0.567 [0.397; 0.810]; p = 0.002).While laparoscopic IPOM showed a favorable relationship with the postoperative complications and complication-related reoperations, it demonstrated an unfavorable association with the intraoperative complications, general complications, recurrence rate and pain rates. CONCLUSION: Suture repair continues to be used for 78% of umbilical hernias with a defect < 2 cm. While suture repair has a favorable influence on the rates of postoperative complications and complication-related reoperations, it has a higher risk of recurrence. Female gender also has an unfavorable influence on the recurrence rate. Laparoscopic IPOM appears to be indicated only in settings of obesity (BMI ≥ 30).