Patient-reported outcomes: using ESAS to screen for anemia

Patient perspectives of their symptom burden provide valuable data to clinicians. We have investigated the Edmonton Symptom Assessment Scale (ESAS) extensively in our radiation oncology and supportive care clinics. We were interested in examining whether ESAS data could correlate with anemia.

Our clinics have used a modified ESAS since 2015; patients now input data directly into the electronic medical record using a tablet interface. Of 9813 patients providing ESAS reports, we retrieved hemoglobin (Hb) data from 8304. Of these, 1351 patients had both performed on the same day. Anemia existed if Hb was < 13.0 g/L (man) or < 12 g/L (woman).

When self-reported scores for both tiredness and shortness of breath were 7 and above, the positive predictive value (PPV) for anemia was 80%, and specificity was 97.6%. Corresponding sensitivity was 8.2% and accuracy was 48.9%. This 2-item model could be a valuable screening tool for lack of anemia in cancer patients in the outpatient setting: if patients rate both these ESAS items < 7, there exists < 3% false positive risk. An expanded 5-item model adding lack of appetite, pain, and bone marrow primary site increased sensitivity and accuracy at the expense of specificity and PPV. We consider this less clinically functional than the two-item screen.

This is one of the first reports of PRO data screening for a clinical sign, in this case, anemia. Predicting freedom from anemia is feasible using 2 ESAS survey questions: tiredness and shortness of breath.