Obesity in the United States continues to increase and is projected to affect 41% of the population by 2030 [1]. This trend has important implications for surgical practice, particularly in abdominal wall reconstruction. Elevated body mass index (BMI) is a well-established risk factor for ventral and incisional hernia formation, driven by increased intra-abdominal pressure, abdominal wall strain, and impaired wound healing [2, 3]. Obesity is also associated with higher rates of postoperative complications, prolonged length of stay, and hernia recurrence [4].

Management of patients with obesity undergoing ventral hernia repair (VHR) remains challenging. Many surgeons defer elective repair above specific BMI thresholds, commonly 35 kg/m², despite the absence of universally accepted guidance for patients with class II-III obesity [5, 6]. This approach aims to reduce perioperative morbidity and recurrence risk; however, it may delay care in symptomatic patients. Preoperative weight loss is often difficult to achieve, and deferral of surgery has been associated with failure to undergo elective repair and increased likelihood of emergent intervention, which carries worse outcomes [7, 8].

Minimally invasive surgery (MIS) techniques have altered the risk profile of VHR and may mitigate obesity-associated morbidity. Compared with open repair, MIS approaches are associated with reduced wound complications, postoperative pain, and length of stay [9, 10]. Intraperitoneal onlay mesh (IPOM; without defect closure) and intraperitoneal onlay mesh plus (IPOM+; with defect closure) require less tissue dissection than retromuscular approaches and have demonstrated acceptable recurrence rates in selected populations [11]. However, the optimal BMI range for these approaches in patients with severe obesity remains understudied.

In this study, we evaluated postoperative outcomes following minimally invasive VHR in patients with BMI ≥40 kg/m², with a focus on hernia recurrence and perioperative complications. We hypothesized that MIS VHR could be performed in this high-risk population with acceptable perioperative outcomes and explored factors potentially associated with recurrence.

In this cohort of patients with class III obesity undergoing minimally invasive ventral hernia repair, we observed low short-term morbidity but a radiologic recurrence rate of 17.3%, which is on the higher end of recurrence rates reported after minimally invasive VHR and should not be characterized as low. This is likely attributable to several factors specific to this cohort, including prolonged and non-standardized imaging follow-up (median 793 days, with some patients followed beyond 3 years), a high proportion of incisional and recurrent incisional hernias (71.2% of the cohort), and use of radiologic rather than clinical recurrence as the primary endpoint, which is expected to capture asymptomatic and subclinical failures that would otherwise be missed on physical examination alone. Among patients with recurrence, the median time to CT-confirmed recurrence was 1208 days (IQR, 351–1694), indicating that clinically meaningful recurrence continued to accrue well beyond the first postoperative year. In unadjusted comparisons, we did not observe statistically distinguishable associations between recurrence and individual technical variables (including defect closure, mesh fixation, or suture type); however, the limited number of events constrains precision and increases the likelihood of false-negative findings. Recurrence occurred exclusively in incisional and recurrent incisional hernias, a pattern considered further below. Greater postoperative weight loss was associated with increased recurrence; given the observational design and time-dependent follow-up, causality cannot be inferred.

Long-term outcomes after ventral hernia repair in patients with class III obesity are not well characterized. In population-based data with complete follow-up, reoperation for recurrence after elective incisional hernia repair continued to accrue throughout 5 years of observation, indicating that recurrence risk does not plateau within the first postoperative years [12]. Our median imaging follow-up of 793 days therefore reflects mid-term rather than long-term durability, and the 17.3% radiologic recurrence rate reported here is best regarded as a lower bound on what would be observed with longer, protocol-driven surveillance. Comparable long-term data restricted to patients with BMI ≥40 kg/m² undergoing minimally invasive repair are, to our knowledge, not available, and this remains an important gap in the literature.

Obesity is consistently associated with worse outcomes following ventral hernia repair, particularly in open surgery, where higher complication and recurrence rates have been well documented [6, 13]. However, evidence supporting specific BMI thresholds for surgical eligibility remains limited [14]. Large registry studies demonstrate increasing risk with higher BMI, yet analyses focused on minimally invasive repair suggest attenuation of this effect [7, 15]. In an ACS-NSQIP analysis, only BMI ≥50 kg/m² was independently associated with complications after minimally invasive VHR [3]. A systematic review and meta-analysis of 11 studies and 3,199 patients found no significant differences in hernia recurrence, seroma, or SSI rates among patients with BMI >40 kg/m² undergoing minimally invasive VHR [16]. Similarly, Maspero et al. found that class III obesity was not associated with higher complication or recurrence rates after laparoscopic repair [2].

Recurrence was not independently associated with operative technique or any mesh-related variable; however, given the limited sample size and event count, this null finding should not be interpreted as evidence that technical factors do not influence repair durability, and larger, adequately powered studies are needed to clarify these associations. Recurrence appeared more closely associated with hernia phenotype than with the technical variables evaluated, occurring only in incisional and recurrent incisional hernias, consistent with prior evidence that defect complexity is a key determinant of failure [17, 18]. Parker et al., in a systematic review and meta-analysis of 274 studies, confirmed that recurrent hernia type is an independent prognostic factor for recurrence, above and beyond BMI alone [17].

This stepwise concentration of recurrence, from 0% in primary hernias to 12.5% in incisional hernias to 33.3% in recurrent incisional hernias, is consistent with the “vicious cycle” model of ventral hernia repair described by Holihan et al., in which postoperative complications increase the risk of recurrence and recurrence leads to further repair, with each successive operation leaving the abdominal wall more scarred, less vascularized, and structurally weaker than at the prior operation, so that each subsequent repair attempt carries a progressively higher risk of failure [19]. No 30-day complications were recorded among the patients who later developed recurrence in this cohort, so the complication-driven component of this cycle could not be observed directly; the stepwise gradient across hernia phenotypes is nonetheless consistent with its structural component. Under this framework, recurrent incisional hernia is not simply a more severe variant of incisional hernia, but a distinct risk state shaped by the cumulative physiological toll of prior surgery, independent of BMI.

No patient who underwent concomitant diastasis repair (0 of 5) developed a hernia recurrence, compared with 9 of 47 patients (19.1%) who did not undergo diastasis repair. This difference did not reach statistical significance (p = 0.573), and the small number of diastasis repairs limits any firm inference; however, the finding is mechanistically plausible and merits comment. Unaddressed diastasis may leave residual midline laxity and altered load distribution across the abdominal wall, which could plausibly place additional mechanical strain on the primary repair site over time. Considered alongside the weight-loss association described below, this observation raises the possibility that dynamic biomechanical factors of the abdominal wall, beyond the technical repair itself, contribute to recurrence in this population; this hypothesis warrants dedicated prospective evaluation.

Case acuity and hernia type also bear on the interpretation of these findings. No primary hernia recurred (0 of 15), a favorable signal; however, primary hernias in this cohort were by definition less likely to be complex or previously repaired, which likely explains this finding at least as much as any inherent protective effect of the primary phenotype itself. Among the two emergent repairs, one recurrence occurred, and among the nine urgent repairs, one recurrence occurred. These numbers are too small to support formal statistical comparison and are presented descriptively; the higher perioperative morbidity associated with emergent repair in this population is considered below.

The association between greater postoperative weight loss and recurrence is unexpected. One possible explanation is that substantial weight reduction alters abdominal wall mechanics and reduces tension across the repair, potentially destabilizing the mesh-tissue interface [20]. Prior work by Schlosser et al. demonstrated that weight change significantly impacts intra-abdominal and hernia volumes, providing a plausible mechanical basis for this observation [21]. Three alternative interpretations warrant consideration. First, reverse causation: patients with subclinical recurrence may experience altered abdominal wall integrity, caloric intake, or activity, which may contribute to weight change rather than the reverse. Second, ascertainment bias: patients who lose weight may be more likely to undergo repeated imaging, increasing the probability of detecting otherwise occult recurrence. Third, differential follow-up time and the use of the “most recent” weight/BMI (rather than a standardized timepoint) may inflate between-group differences if recurrence status correlates with duration or intensity of clinical observation. None of these mechanisms can be excluded by the present design.

Deferral of repair carries its own risks. A large NSQIP analysis showed that obese patients are disproportionately represented in emergent VHR, with complication rates nearly doubling [22]. Liu et al. identified a BMI of 35.3 kg/m² as a statistically derived recurrence threshold [23], yet a recent systematic review found that BMI does not independently affect recurrence after open abdominal wall reconstruction, reinforcing the need for individualized patient selection [24]. In a cohort restricted to BMI ≥40 kg/m², such thresholds should be viewed as context-setting rather than prescriptive, and decisions should remain phenotype- and risk-based.

This study has several important limitations that should temper interpretation of our findings. It is a small, single-center, retrospective series of 52 patients with only 9 recurrence events; a study of this size is not powered to support strong clinical conclusions and should be regarded as exploratory and hypothesis-generating rather than confirmatory. All comparisons are unadjusted, and the limited event count precluded meaningful multivariable modeling; we therefore cannot exclude confounding by unmeasured or imprecisely measured variables, and associations that did not reach significance in this sample (such as male sex, p = 0.057) may still reflect a true effect that this study was underpowered to detect.

Restricting inclusion to patients with postoperative imaging follow-up may have introduced selection or ascertainment bias, as clinicians may have preferentially ordered CT imaging in patients with symptoms or clinical concern for recurrence, potentially inflating the observed recurrence rate relative to the full operative cohort. In addition, all procedures were performed by attending surgeons within a single, high-volume Division of MIS and Bariatric Surgery, whose comfort and expertise in operating on patients with severe obesity and in performing complex minimally invasive abdominal wall reconstruction likely exceed that of general surgeons in most practice settings; the low short-term morbidity observed here may reflect this concentrated expertise rather than the safety of MIS VHR at this BMI threshold more broadly, and our results should not be generalized to lower-volume centers or to surgeons without comparable subspecialty training. Heterogeneity in operative technique, mesh selection, and fixation across a 12-year, multi-surgeon experience further limits the ability to draw technique-specific conclusions. The association between postoperative weight loss and recurrence should be interpreted with particular caution given the observational design, the use of “most recent” weight rather than a standardized timepoint, and the potential for reverse causation and ascertainment bias discussed above. Strengths of this study include imaging-based follow-up with explicitly reported CT intervals, use of objective radiologic recurrence rather than clinical recurrence alone, and inclusion of consecutive patients at a high-volume academic center with prospectively maintained data capture.

Several considerations follow for future study of this population. First, prospective multicenter collaboration or registry-based designs will be required to accumulate sufficient events for multivariable modeling, since single-center cohorts of this size cannot support adjusted analysis. Second, imaging follow-up should be protocol-driven and obtained at prespecified intervals rather than clinically indicated, which would remove the ascertainment bias inherent to our design and permit valid time-to-event analysis. Third, postoperative weight should be recorded at standardized timepoints so that the relationship between weight trajectory and recurrence can be assessed without the confounding introduced by variable follow-up duration. Fourth, the apparent signal associated with concomitant diastasis repair, and more broadly the contribution of abdominal wall biomechanics to repair durability, merits dedicated prospective evaluation. Finally, studies in this population should report patient-reported outcomes and long-term durability alongside recurrence, since the question facing surgeons is not only whether repair is technically feasible but whether it durably benefits the patient.

In this exploratory single-center cohort, MIS VHR in patients with class III obesity was associated with low short-term morbidity, but the mid-term radiologic recurrence rate of 17.3% should not be characterized as low, and it reached 24.3% once primary hernias were excluded. Recurrence was observed exclusively in incisional and recurrent incisional hernias; associations with the technical variables evaluated did not reach statistical significance, and this study was not powered to compare these factors against one another. Given the retrospective design, limited sample size, and small number of recurrence events, these findings should be interpreted cautiously and considered hypothesis-generating. Larger prospective multicenter studies with protocol-driven, longer-term imaging follow-up are needed to confirm these observations, to characterize long-term durability in this population, and to better define patient selection and factors associated with durable repair.