What is the best term in Spanish to express the concept of cancer-related fatigue?

Abstract

Introduction: Fatigue is one of the most frequent symptoms in patients with cancer. No adequate term in Spanish has been defined to describe the English concept of fatigue.

Aim: To identify the most suitable Spanish words that define the concept of fatigue and to check psychometric characteristics.

Method: Consensus with professional experts on Spanish words that best suit the English concept of fatigue. A prospective study on oncologic patients was also undertaken, which included an evaluation of the intensity of fatigue through visual numeric scales (VNS) where the words had been previously selected. The fatigue subscale of the Functional Assessment of Cancer Therapy-Fatigue (FACT-F) questionnaire was taken as a reference.

Results: The experts highlighted the words cansancio, agotamiento, and debilidad (tiredness, exhaustion, and weakness) as the terms that best defined the concept of fatigue. In the psychometric assessment study, 100 patients were included, of which 61 (61%) presented diagnostic values for cancer-related fatigue in the FACT-F fatigue subscale (score 34/52 or lower). The VNS for the chosen terms obtained a high correlation with the FACT-F fatigue subscale results: cansancio (tiredness) r = −0.71, agotamiento (exhaustion) r = −0.74, debilidad (weakness) r = −0.74, with no statistical differences between them. For the detection of fatigue by means of the VNS, tiredness (cutoff point ≥4/10) gave sensitivity (S) 0.90 and specificity (E) 0.72; exhaustion (cutoff point ≥3/10) S 0.95 and E 0.90 and weakness (cutoff point ≥4/10) S 0.92 and E 0.72. The ROC curve was 0.88 for tiredness, 0.94 for exhaustion, and 0.92 for weakness, with no significant difference between the areas mentioned. The terms cansancio, agotamiento, and debilidad (tiredness, exhaustion, and weakness) are suitable for defining the English concept of fatigue in Spanish, and should be the preferred option for inclusion in evaluation tools.