Safety and outcome of elective synthetic mesh repair for incisional ventral hernias in immunosuppressed patients - a retrospective propensity-score-matched analysis.

Introduction: Incisional hernia remain an important complication after abdominal surgery. Repair often includes use of synthetic mesh, but certain risk factors for complication after mesh hernia repair have been described. Among these, immunosuppression due to co-existing conditions is hypothesized to increase postoperative complications, but data is scarce and contradicting. Therefore, the aim was to assess outcome after mesh hernia repair in immunosuppressed patients.

Material & Methods: Patients with and without immunosuppression undergoing elective incisional hernia repair at our clinic between 2010 and 2019 were analyzed in this retrospective study. Pre-existing conditions, details of immunosuppression, postoperative course and outpatient follow-up for hernia recurrence were collected and impact of clinical variables on outcome was analyzed. Propensity score matching was performed for comparison of cohorts.

Results: Immunosuppression was associated with increased postoperative complications in the overall cohort of 732 patients undergoing incisional ventral hernia repair in univariate but not multivariate analysis (p = 0.036 and p = 0.25, respectively). Overall postoperative complications did not differ between patients with immunosuppression compared to the matched collective. However, use of > 2 immune suppressive agents and immunosuppression history > 48 months showed significant impact on postoperative complications in univariate and multivariate analysis (p = 0.003/p = 0.023 and p = 0.018/p = 0.03, respectively). Age (< 60 years), duration of surgery (> 120 min), midline hernia according to EHS classification and number of immunosuppressive agents administered were identified as important risk factors for recurrence in immunocompromised patients (p = 0.045, p = 0.023, p = 0.012 and 0.049, respectively).

Conclusion: In this study, overall safety with desirable outcome of mesh implantation in immunosuppressed patients was documented. Furthermore, data suggested significant impact of number of immunosuppressive agents as a predicator of postoperative complications in this collective, possibly enabling risk stratification within this subgroup.