Abstract
BACKGROUND: Enrollment of Medicare beneficiaries in medicare advantage (MA) plans has been steadily increasing. Prior research has shown differences in healthcare access and outcomes based on Medicare enrollment status. This study sought to compare utilization of minimally invasive colorectal cancer (CRC) surgery and postoperative outcomes between MA and Fee-for-Service (FFS) beneficiaries. METHODS: A retrospective cohort study of beneficiaries ≥ 65.5 years of age enrolled in FFS and MA plans was performed of patients undergoing a CRC resection from 2016 to 2019. The primary outcome was operative approach, defined as minimally invasive (laparoscopic) or open. Secondary outcomes included robotic assistance, hospital length-of-stay, mortality, discharge disposition, and hospital readmission. Using balancing weights, we performed a tapered analysis to examine outcomes with adjustment for potential confounders. RESULTS: MA beneficiaries were less likely to have lymph node (12.9 vs 14.4%, p < 0.001) or distant metastases (15.5% vs 17.0%, p < 0.001), and less likely to receive chemotherapy (6.2% vs 6.7%, p < 0.001), compared to FFS beneficiaries. MA beneficiaries had a higher risk-adjusted likelihood of undergoing laparoscopic CRC resection (OR 1.12 (1.10-1.15), p < 0.001), and similar rates of robotic assistance (OR 1.00 (0.97-1.03), p = 0.912), compared to FFS beneficiaries. There were no differences in risk-adjusted length-of-stay (β coefficient 0.03 (- 0.05-0.10), p = 0.461) or mortality at 30-60-and 90-days (OR 0.99 (0.95-1.04), p = 0.787; OR 1.00 (0.96-1.04), p = 0.815; OR 0.98 (0.95-1.02), p = 0.380). MA beneficiaries had a lower likelihood of non-routine disposition (OR 0.77 (0.75-0.78), p < 0.001) and readmission at 30-60-and 90-days (OR 0.76 (0.73-0.80), p < 0.001; OR 0.78 (0.75-0.81), p < 0.001; OR 0.79 (0.76-0.81), p < 0.001). CONCLUSIONS: MA beneficiaries had less advanced disease at the time of CRC resection and a greater likelihood of undergoing a laparoscopic procedure. MA enrollment is associated with improved health outcomes for elderly beneficiaries undergoing operative treatment for CRC.