Occurrence and Characteristics of Hospitalizations During First-Line Chemotherapy Among Individuals with Metastatic Colorectal Cancer

Objective Choosing chemotherapy for metastatic colorectal cancer (mCRC) requires balancing clinical effectiveness and risk of complications. This study characterized real-world inpatient/emergency department (ED) hospitalizations during first-line chemotherapy among individuals with mCRC. Methods This retrospective cohort study used data from medical and pharmacy claims. All patients had mCRC with ≥1 claim for ≥1 of the 5 most frequently utilized first-line chemotherapy agents (fluorouracil, oxaliplatin, bevacizumab, irinotecan, capecitabine). The main outcome was all-cause hospitalizations (inpatient or ED setting) identified from claims via ICD-9/10-CM coding from index date until 30 days after the end of first-line chemotherapy or last available data. Results A total of 717 individuals (mean age 55 years; 58% male; ECOG 0/1/2+/missing in 44%/39%/6%/11%; median follow-up 116 days) met study criteria. Thirty-four distinct chemotherapy regimens were used. Overall, 40% of patients had ≥1 hospitalization (n=285; total 415 hospitalizations); 12% (n=85) had ≥2 hospitalizations. The median time to first hospitalization was 52 days; median inpatient length of stay was 4 days; infections/neutropenia (21%) and bowel-related complications (17%) were the most common issues associated with inpatient hospitalizations. In univariate analyses, insurance plan type, geographical location, ECOG, and renal disease were associated with hospitalization. In multivariable analyses, ECOG ≥1 was associated with a 67% increase (p