Emergency presentation of cancer and subsequent care fragmentation: A SEER-Medicare study.

516 Background: Emergency presentation (EP) of cancer, defined as cancer diagnosis through unplanned ED visits, is associated with advanced disease and worse survival. We hypothesized that (1) individuals with EP may have more fragmented care than those diagnosed in routine outpatient encounters, which may contribute to worse outcomes, and (2) EP-fragmentation patterns vary depending on the subsequent care pathway following an EP. Methods: Using SEER-Medicare data (2008–2019), we identified fee-for-service beneficiaries aged 66+ with newly diagnosed breast, colorectal, lung, ovarian, prostate, or uterine cancer. EP was categorized as diagnosis during an emergency inpatient admission (inpatient EP), or via outpatient care after an emergency visit (outpatient EP). We assessed different types of fragmentation: 1) “outpatient” via inversed Bice-Boxerman index, 2) “acute-care” via inversed ratio of facilities to encounters, 3) “care transitions” via inpatient stays, transfers, and discharges, and 4) “early-treatment” as multiple vs. single facility for surgery/chemotherapy/radiation. We estimated odds ratios (ORs) for each type of fragmentation using logistic regression, adjusting for sociodemographic and clinical characteristics and prior utilization over multiple follow-up periods. Results: Among 530,662 Medicare beneficiaries, EP and care fragmentation associations varied by diagnosis pathway and fragmentation types. EP patients consistently had lower outpatient fragmentation compared to non-EP ≤6 months of diagnosis (inpatient EP OR 0.81, 95% CI 0.78-0.84; outpatient EP 0.92, 0.89-0.96), and ≤12 months (0.83, 0.81-0.86; 0.96, 0.93-1.00). Conversely, compared to non-EPs, acute-care fragmentation was higher for outpatient EPs (OR 1.10, 95% CI 1.07-1.15) but similar for inpatient EPs (1.02, 0.99-1.08). Compared to non-EPs, care transitions were markedly higher for inpatient EPs (≥3 stays OR 1.88, 95% CI 1.83-1.93; ≥2 transfers 1.59, 1.51-1.67; ≥3 discharges 1.54, 1.50-1.58) but similar for outpatient EPs (1.04, 1.01-1.08; 1.01, 0.94-1.09; 1.10, 1.07-1.14). Early-treatment fragmentation was slightly higher for outpatient EPs (1.10, 1.06-1.14) but lower for inpatient EPs (0.86, 0.84-0.89). Conclusions: EP of cancer is associated with care fragmentation, and the association varies by specific EP pathway and fragmentation type. Those diagnosed during emergency inpatient admission have lower early treatment fragmentation but markedly higher transitions while those diagnosed after ED referral experience higher acute-care dispersion and early-treatment fragmentation, highlighting the importance of separating these groups. Our findings provide some clues towards understanding the drivers of reduced survival among EPs, such as through breakdowns in care coordination and less time for advance care planning, particularly when care is primarily received in acute care settings.