Primary and incisional ventral hernias are different in terms of patient characteristics and postoperative complications - A prospective cohort study of 4,565 patients.

BACKGROUND: Primary and incisional hernias are often pooled in publications studying hernia symptoms, treatment, or surgical outcomes. The question rises whether this is justified or if primary and incisional hernia should be considered as two separate entities. The aim of this prospective cohort study is to compare primary and incisional ventral hernias regarding patient characteristics, hernia characteristics, surgical characteristics, and postoperative complications.

MATERIALS AND METHODS: A registry-based, prospective cohort study was performed. All patients undergoing primary or incisional hernia repair surgery between September 1st, 2011 and February 29th, 2016 were included. Patient baseline characteristics, hernia characteristics, surgical characteristics, and postoperative outcomes were collected and analyzed.

RESULTS: A total of 4565 patients were included, of whom 2374 had a primary hernia and 2191 had an incisional hernia. All patient, hernia, and surgical characteristics were statistically significantly different between primary and incisional hernias except for corticosteroid use, history of inguinal hernia, incarceration, and emergency surgery. Overall complication rates (wound, surgical, and medical) were significantly different (105/2374 (4.4%) for primary hernia versus 323/2191 (15%) for incisional hernia, p < 0.001).

CONCLUSION: Primary and incisional hernia are statistically significantly different for almost all patient, hernia, surgical, and postoperative characteristics analyzed. Given these differences, data on primary hernias and incisional hernias should not be pooled in studies reporting on hernia repair.