Breast cancer treatments are associated with frequent and sometimes severe adverse effects that may significantly impair quality of life and lead to functional disability. Chronic pain and cognitive impairment are common treatment-related complications. However, no study has yet investigated the influence of cancer treatment-related cognitive impairment on chronic pain in this population.
Primary Objective:
To evaluate the influence of cognitive impairment, defined as a significant alteration in the Global Composite Score (GCS), measured 6 months (±1 week) after completion of chemotherapy, on chronic pain over a one-year period following inclusion. Chronic pain is defined as persistent pain intensity ≥4.
The GCS includes 8 measures derived from cognitive tests assessing long-term memory, inhibition, cognitive flexibility, verbal fluency (categorical and phonemic), nonverbal fluency, working memory, and phasic attention.
The primary endpoint is the comparison of the percentage of patients with chronic pain between patients with and without cognitive impairment at 6 months after chemotherapy completion (T3).
Secondary Objectives:
1. Compare the percentage of chronic pain in patients with and without cognitive impairment at T2 (±2 weeks after chemotherapy completion), based on persistent pain intensity ≥4/10 on the Brief Pain Inventory (BPI).
2. Compare chronic pain characteristics and pain-related disability between patients with and without cognitive impairment at T2 and T3, including etiology, incidence, severity, localization, and disability. Pain characteristics will be assessed using the BPI, McGill Pain Questionnaire, DN4, NPSI, and a body diagram.
3. Compare, at T2 and T3, cognitive test scores used to calculate the GCS in patients with chronic pain to determine whether impairment in specific cognitive functions has a greater influence on chronic pain.
4. Compare the percentage of chronic pain in patients with cognitive complaints versus those without cognitive complaints at T2 and T3. Cognitive complaints will be assessed using the FACT-Cog and WMQ questionnaires.
5. Evaluate the influence of cognitive impairment on pain coping strategies at T2 and T3 using the Coping Strategies Questionnaire (CSQ).
6. Evaluate the influence of cognitive impairment on fatigue, anxiety, depressive symptoms, and sleep disturbances in patients with and without chronic pain at T2 and T3. Fatigue will be assessed using the MFI, sleep disturbances using the PSQI, and anxiety/depressive symptoms using the HADS.
Assessments will be performed at the following time points:
T1: before chemotherapy, but after surgery T2: after completion of chemotherapy (± 2 weeks) T3: 6 months after completion of chemotherapy (± 1 week)