Effects of laparoscopic vs open abdominal surgery on costs and hospital readmission rate and its effect modification by surgeons’ case volume

Background: Laparoscopy provides a minimally invasive alternative to open abdominal surgery. Current data describing its association with hospital readmission and costs in relation to surgeon laparoscopic case volume is limited to smaller databases and subsets of operations. Methods: This retrospective cohort study of 23,285 adult abdominal operations from 2007 to 2015 compares 30-day readmission rate and costs between laparoscopic and open abdominal operations and examines effect modification by surgeon laparoscopic case volume. Outcomes were all-cause hospital readmission within 30 days after discharge and index hospital admission cost. Results: All-cause hospital readmission rates were significantly lower after laparoscopic abdominal operations compared with open operations (adjusted odds ratio [aOR] 0.56, 95% CI 0.46–0.69, p ' 0.001) with a difference in readmission risk attributable to laparoscopic approach of − 4.0% (95% CI − 5.4 to − 2.6%) in complete-case analysis. Among surgeons with a high laparoscopic case volume, the estimated difference in readmission risk through laparoscopy was magnified (− 5.8%, 95% CI − 7.5 to − 4.1%) compared to low surgeon laparoscopic case volume (− 2.9%, 95% CI − 4.8 to −1.1%, p for interaction = 0.005). The estimated difference in costs of the index hospital admission attributable to laparoscopic approach was − $3869 (95% CI − $4200 to − $3538; adjusted incidence rate ratio 0.77, 95% CI 0.75–0.79, p ' 0.001). Laparoscopy was followed by significantly lower rates of readmissions related to gastrointestinal (aOR 0.68, 95% CI 0.55–0.85, p = 0.001), wound complications (infection: aOR 0.33, 95% CI 0.23–0.47, p ' 0.001; non-infectious: aOR 0.47, 95% CI 0.30–0.74, p = 0.001), and malignancy (aOR 0.68, 95% CI 0.55–0.85, p ' 0.001). The findings remain robust after multiple imputation and sensitivity analyses. Conclusions: Laparoscopy versus open abdominal surgery is associated with reduced hospital readmissions related to malignancy, gastrointestinal, and wound complications. Effect modification by higher laparoscopy case volume argues for continued proliferation of laparoscopy in abdominal surgeries.