Use of Fecal Immunochemical Testing in Acute Patient Care in a Safety Net Hospital System

Objective: To characterize and analyze the prevalence, indications for, and outcomes of fecal immunochemical testing (FIT) in acute patient care within a safety net health care system’s emergency departments (EDs) and inpatient settings. Design: Retrospective cohort study derived from administrative data. Setting: A large, urban, safety net health care delivery system in Texas. The data gathered were from the health care system’s 2 primary hospitals and their associated EDs. This health care system utilizes FIT exclusively for fecal occult blood testing. Participants: Adults ≥18 years who underwent FIT in the ED or inpatient setting between August 2016 and March 2017. Chart review abstractions were performed on a sample (n = 382) from the larger subset. Measurements: Primary data points included total FITs performed in acute patient care during the study period, basic demographic data, FIT indications, FIT result, receipt of invasive diagnostic follow-up, and result of invasive diagnostic follow-up. Multivariable log-binomial regression was used to calculate risk ratios (RRs) to assess the association between FIT result and receipt of diagnostic follow-up. Chi-square analysis was used to compare the proportion of abnormal findings on diagnostic follow-up by FIT result. Results: During the 8-month study period, 2718 FITs were performed in the ED and inpatient setting, comprising 5.7% of system-wide FITs. Of the 382 patients included in the chart review who underwent acute care FIT, a majority had their test performed in the ED (304, 79.6%), 133 of which were positive (34.8%). The most common indication for FIT was evidence of overt gastrointestinal (GI) bleed (207, 54.2%), followed by anemia (84, 22.0%). While a positive FIT result was significantly associated with obtaining a diagnostic exam in multivariate analysis (RR, 1.72; P < 0.001), having signs of overt GI bleeding was a stronger predictor of diagnostic follow-up (RR, 2.00; P = 0.003). Of patients who underwent FIT and received diagnostic follow-up (n = 110), 48.2% were FIT negative. These patients were just as likely to have an abnormal finding as FITpositive patients (90.6% vs 91.2%; P = 0.86). Of the 382 patients in the study, 4 (1.0%) were subsequently diagnosed with colorectal cancer (CRC). Of those 4 patients, 1 (25%) was FIT positive. Conclusion: FIT is being utilized in acute patient care outside of its established indication for CRC screening in asymptomatic, average-risk adults. Our study demonstrates that FIT is not useful in acute patient care.