Symptom clusters using the Brief Pain Inventory in patients with breast cancer

BACKGROUND: The purpose of this study was to assess symptom clusters in functional interference using the brief pain inventory (BPI) in patients with non-metastatic breast cancer (BC) during and after chemotherapy. METHODS: A principal component analysis with varimax rotation was conducted on data from 228 patients to identify two clusters at baseline and two intervals following treatment. RESULTS: Physical (general activity, normal work, walking ability) and psychosocial (mood, relationships, sleep, enjoyment of life) interference clusters were present at baseline. Clusters were observed at 1-month (cluster 1: general activity, normal work, enjoyment of life; cluster 2: relationships, sleep) and 3-month (cluster 1: general activity, normal work, relationships; cluster 2: sleep, enjoyment of life) post-treatment. CONCLUSIONS: Results from our study suggest dynamic symptom clusters in this patient population, and encourage continued symptom management following completion of treatment.