Original Article

Predictors of Endoscopic and Laboratory Evaluation of Iron Deficiency Anemia in Hospitalized Patients

Authors: George N. Ioannou, MD, MS, Jeremy Spector, MD, Don C. Rockey, MD

Abstract

Background: Many hospitalized anemic patients do not undergo appropriate evaluation. We hypothesized that specific clinical variables were likely to be important in triggering evaluation for iron deficiency anemia.


Methods: We prospectively identified 637 consecutive anemic patients without acute gastrointestinal bleeding admitted over a three-month period to medical inpatient teams of two teaching hospitals and examined clinical variables that predicted diagnostic evaluation.


Results: Serum ferritin or serum transferrin saturation (TS) were measured in 43% (271/637) of subjects and were low in 38% (102/271). Predictors of serum ferritin or TS measurement included low hemoglobin concentration and a history of iron supplementation. Predictors of iron deficiency included low hemoglobin concentration (OR 1.9, 95% CI 1.06–3.5) and low mean cell volume (OR 4.6, 95% CI 2.5–8.6). Of 102 patients with iron deficiency anemia, 31% underwent endoscopic evaluation, and 39% had serious gastrointestinal lesions. The only significant predictor of having an endoscopic evaluation was a positive fecal occult blood test (FOBT) (OR 5.2, 95% CI 1.7–16.2).


Conclusions: In patients with anemia, tests to ascertain iron status are not appropriately performed in hospitalized patients. Patients found to have iron deficiency anemia who are FOBT-positive undergo endoscopic evaluation more frequently than FOBT-negative patients.


Key Points


* Serum ferritin or serum transferrin saturation (TS) were measured in less than half of patients admitted with anemia.


* In patients with iron deficiency anemia, follow-up tests to determine the cause of iron deficiency anemia are not appropriately performed.


* Patients found to have iron deficiency anemia who are FOBT-positive undergo endoscopic evaluation more frequently than FOBT-negative patients.

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