Clinical Features, <scp>CT</scp> Imaging Decisions and Yield by Age in Adults With Abdominal Pain in the Emergency Department

OBJECTIVES: Older adults with abdominal pain present diagnostic uncertainty due to less informative histories/exams, broader etiologies, and higher morbidity. Whether ED imaging decisions are calibrated to this risk is unclear. The objective of this study was to compare age-stratified clinical features, CT utilization, and CT diagnostic yield, and to assess how history/physical and clinician pretest suspicion relate to adverse outcomes. METHODS: This was a retrospective cohort analysis of data from a prospective cohort collected from March 2016-January 2017 at a single community teaching hospital emergency department in southwest Baltimore. We analyzed 1169 visits of adults presenting with nontraumatic abdominal pain including 229 (19.6%) aged ≥ 60 years. Patients < 18 years were excluded. Age groups were 18-39, 40-59, ≥ 60 years. Outcomes were CT ordering, acute actionable CT findings, admission, surgery, and a composite of adverse outcomes (any actionable CT finding, admission, surgery, or Emergency General Surgical diagnosis). History and physical examination operating characteristics (e.g., sensitivity/specificity of tenderness, rebound) were also calculated. RESULTS: Of 1169 visits, 19.6% were aged ≥ 60 years. CT ordering increased with age (41.7%, 66.2%, 70.7% for 18-39, 40-59, ≥ 60; p < 0.001), as did CT yield (18.4%, 31.2%, 37.7%; p < 0.001). Admissions (12.1%, 28.0%, 37.6%) and surgeries (4.6%, 9.0%, 10.6%) also rose with age. Clinician pretest suspicion was similar across age groups. Abdominal tenderness was less sensitive for adverse outcomes in older adults (sensitivity 0.58 in ≥ 60 vs. 0.73 in 18-39 and 0.73 in 40-59), while rebound tenderness was highly specific across ages (specificity 0.98, 0.96, 0.98). The number of potential diagnoses to consider rose with age. CONCLUSION: In this cohort, CT use and positivity increased with age and key exam findings (e.g., tenderness) being less informative in older adults, despite similar reported clinician pretest suspicion. These results support age-aware imaging decisions and motivate reframing ED abdominal pain as a geriatric-specific chief complaint.