Background: AIs are commonly used for treatment of postmenopausal women with hormone receptor-positive breast cancer for 5-10 years. However, women often experience side effects including musculoskeletal pain and sleep disturbances that lead to treatment discontinuation and worse healthcare-related outcomes. There is a need to understand the impact of adjuvant AI therapy on sleep and activity patterns in treated patients and associations with treatment adherence. This study examines objective and subjective changes in sleep patterns and daytime function in patients starting AI therapy using actigraphy and questionnaires.
Methods: 49 postmenopausal women with hormone receptor-positive breast cancer who completed local surgery and chemotherapy and were planning to start AI therapy were enrolled. Patients completed 10 consecutive days of actigraphy and validated questionnaires to assess pain, sleep quality, fatigue and physical function at baseline and after three months of AI therapy. Changes in actigraphy parameters after 3 months of AI therapy were examined using paired T-tests and associations between actigraphy measures and patient-reported outcomes were examined using Pearson’s correlations.
Results: 42 patients completed the baseline assessment and 22 patients completed the 3 month assessment. 20 patients were excluded due to incomplete actigraphy data (n=3), discontinuation of AI therapy (n=5) or withdrawal from the study per patient preference (n=12) prior to the 3 month assessment. Total 24 hour activity, average activity per minute and maximum activity over a 24 hour period worsened after 3 months of AI therapy (all p-values <0.05). There was a trend towards worse sleep efficiency after 3 months. Patient-reported physical function also decreased after 3 months of AI therapy (p-value <0.05), but pain severity remained unchanged. Worsening patient-reported fatigue after 3 months of AI treatment correlated to a decrease in average activity per minute (r=-0.55, p-value <0.05) and maximum activity over a 24 hour period (r=-0.61, p-value <0.05).