The diagnostic yield of gastroscopy in the evaluation of asymptomatic patients with iron deficiency anemia.

OBJECTIVES

The diagnostic value of upper endoscopy (EGD) in asymptomatic patients with iron deficiency anemia (IDA) remains uncertain, given the low prevalence of upper gastrointestinal (GI) malignancy.

METHODS

We performed a retrospective cohort study comparing asymptomatic patients with laboratory-confirmed IDA to asymptomatic controls referred for pre-bariatric endoscopy. Between-group comparisons assessed demographic, procedural, and endoscopic features. Diagnostic yield was evaluated for clinically significant findings (CSFs) and histologically confirmed malignancy. Diagnostic efficiency was expressed as the number needed to investigate (NNTI). Predictors of CSF and malignancy were identified by multivariable logistic regression, and receiver operating characteristic (ROC) analysis determined optimal age cutoffs.

RESULTS

Among 6,185 IDA patients and 2,010 controls, endoscopic pathology was significantly more frequent in the anemia group. Major CSFs were detected in 8.2 % of IDA patients vs. 2.9 % of controls (p<0.0001), while malignancy occurred in 1.3 vs. 0.1 % (p<0.0001). Diagnostic efficiency was superior in IDA (NNTI˜12 for CSF; <100 for malignancy) compared with controls (>30 and >1,000, respectively). In adjusted models, IDA and age ≥50 years independently predicted CSFs and malignancy, whereas female sex was inversely associated. ROC analysis identified optimal age thresholds of approximately 60 years for CSFs and 65 years for malignancy.

CONCLUSIONS

Among asymptomatic patients with IDA, EGD demonstrated a substantially higher yield of CSFs and upper gastrointestinal malignancy than in asymptomatic controls, particularly among older individuals. These findings provide a large real-world benchmark for the isolated diagnostic yield of EGD and may inform future risk-stratified approaches to IDA evaluation.