Extending the value of the National Surgical Quality Improvement Program claims dataset to study long-term outcomes: Rate of repeat ventral hernia repair

Abstract

Existing large clinical registries capture short-term follow-up. Yet, there are many important long-term outcomes in surgery, such as recurrence of a ventral hernia after ventral hernia repair. The goal of the current study was to conduct an exploratory analysis to determine whether the rates, timing, and risk factors for ventral hernia re-repair in claims data linked to registry data were consistent with the known clinical literature. The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) and Medicare inpatient claims linked data set from 2005 to 2008 was queried to identify ventral hernia re-repairs after index ventral hernia repairs. Survival analysis was used to examine the ventral hernia re-repair rate over time and to quantify the relationship with clinical variables. Of 3,730 index ventral hernia repairs identified in ACS-NSQIP, 247 patients (6.6%) underwent re-repair of a ventral hernia during the study period (2005-2008) in the Medicare claims data. ACS-NSQIP clinical variables that were associated with the ventral hernia re-repair rate in Medicare claims data 1 year after index ventral hernia repair were being a smoker (hazard ratio [HR] = 1.70, P = .02), body mass index (HR = 1.16, P = .04), and postoperative superficial surgical-site infection (HR = 2.88, P < .001). Long-term rate and timing of ventral hernia re-repair obtained from claims data were an underestimate compared with clinical studies. Yet, several known clinical risk factors for recurrence in the clinical registry were associated with the re-repair rate in claims data at one year. It may be possible to study certain long-term outcomes using selected reoperation rates using the technique of linked clinical registry-claims data, with an understanding that event rates are conservative estimates.