Effects of external beam radiation therapy and androgen deprivation therapy on physical activity of men with non-metastatic prostate cancer.

Abstract

e17028 Background: Physical activity (PA) has been shown to have a profound positive impact on the quality of life of people living with cancer and cancer survivors. However, there has been little research on the changes in PA for patients with prostate cancer despite its high prevalence. External beam radiation therapy (EBRT) and androgen deprivation therapy are standard treatments for non-metastatic prostate cancer (NMPC), although they are accompanied by side effects such as fatigue. Understanding these effects is crucial for identifying interventions to mitigate the consequences of NMPC and its associated treatments. Therefore, this natural history aimed to evaluate how EBRT and ADT influence free-living PA in men with NMPC. Methods: PA data was measured from 68 NMPC patients undergoing EBRT (51 with ADT, 17 without). Participants wore Actical devices around the waist continuously for four days during three assessment points: before EBRT (Time 1), mid-EBRT (Time 2: days 16–22), and end of EBRT (Time 3: days 38–44). PA metrics included Total Activity Counts (TAC), Inactive Time (< 100 counts/min), Light-Intensity Physical Activity (LIPA; ≥100 counts/min; < 1535 counts/min), and Moderate-to-Vigorous Physical Activity (MVPA; ≥1535 counts/min). Results: For men receiving EBRT alone, mean TAC decreased by 1.97%, from 98,791 in time 1 to 96,839 in time 3. Mean IT decreased by 3.16%, from 622.63 minutes in time 1 to 602.93 minutes in time 3. Mean LIPA increased by 11.83% over the same period, from 91.72 minutes to 102.58 minutes. Mean MVPA minutes decreased by 1.41%, from 36.95 minutes in time 1 to 36.43 minutes in time 3. For men receiving EBRT in conjunction with ADT, mean TAC decreased by 16.13%, from 80,534 in time 1 to 67,543 in time 3. Mean IT increased by 3.11%, from 601.13 minutes in time 1 to 619.85 minutes in time 3. Mean LIPA decreased slightly by 0.19%, from 80.34 minutes in time 1 to 80.19 minutes in time 3. Mean MVPA minutes decreased by 20.14%, from 23.34 minutes in time 1 to 18.63 minutes in time 3. ANCOVA revealed significant differences for LIPA (p = 0.024), TAC (p = 0.037), and MVPA (p = 0.0065) when comparing between the ADT (ADT+) and no ADT (ADT-) groups at time 3. Conclusions: Our results showed variability in PA levels among men receiving EBRT alone, with some even increasing their PA levels across treatment. However, men who received EBRT+ADT had significantly less PA than those who received EBRT alone by the end of treatment. This is consistent with previous reports that concomitant use of ADT presents a substantial barrier to maintaining PA levels. We further identify that these consequences are most significant at the end of EBRT treatment. Understanding these treatment specific effects is critically important to identify when patients are most vulnerable, informing interventions aimed at preserving PA through early rehabilitative services.