The assessment of anorexia in patients with cancer: cut-off values for the FAACT–A/CS and the VAS for appetite

Purpose Anorexia is a frequently observed symptom in patients with cancer and is associated with limited food intake and decreased quality of life. Diagnostic instruments such as the Anorexia/Cachexia Subscale (A/CS) of the Functional Assessment of Anorexia/Cachexia Therapy (FAACT) questionnaire and the visual analog scale (VAS) for appetite have been recommended in the assessment of anorexia, but validated cut-off values are lacking. This study aimed to obtain cut-off values of these instruments for the assessment of anorexia in patients with cancer. Methods The FAACT–A/CS and the VAS for appetite were administered to patients with cancer before start of chemotherapy. As reference standard for anorexia, two external criteria were used: (1) a cut-off value of ≥2 on the anorexia symptom scale of the EORTC QLQ C-30 and (2) the question “Do you experience a decreased appetite?” (yes/no). ROC curves were used to examine the optimal cut-off values for the FAACT–A/CS and VAS. Results A total of 273 patients (58 % male; 64.0 ± 10.6 years) were included. The median score on the FAACT–A/CS was 38 (IQR 32–42) points and 77 (IQR 47–93) points on the VAS. Considering both external criteria, the optimal cut-off value for the FAACT–A/CS was ≤37 (sensitivity (se) 80 %, specificity (sp) 81 %, positive predictive value (PV + ) 79 %, negative predictive value (PV − ) 82 %) and for the VAS was ≤70 (se 76 %, sp 83 %, PV + 80 %, PV − 79 %). Conclusions For the assessment of anorexia in patients with cancer, our study suggests cut-off values of ≤37 for the FAACT–A/CS and ≤70 for the VAS. Future studies should confirm our findings in other patient samples.