Impact of chemotherapy on medium-term physical function and activity of older breast cancer survivors, and associated biomarkers

Abstract Objective Chemotherapy is less often prescribed in older individuals due to concerns about post-treatment morbidity and quality of life. We evaluated the physical performance of breast cancer survivors treated with and without adjuvant chemotherapy. Materials and Methods We conducted a case–control study in 56 estrogen receptor positive breast cancer survivors (BCS) on adjuvant aromatase inhibitors 1–2 years after definitive surgery. Cases had received adjuvant chemotherapy (n = 27; age 70.5 ± 3.6 years) versus age-matched controls who had not (n = 29; age 70.0 ± 4.3 years). Measures of grip strength, physical activity and performance, walking speed, fatigue, and self-reported physical function were collected. Biological correlates of inflammation, frailty and markers of DNA and RNA oxidation were compared. Results Grip strength (controls: 21 ± 7.4 vs. cases: 29.7 ± 5.0 kg, p = 0.20), physical activity (5403 ± 3204 vs. 6801 ± 9320 steps/day, p = 0.45), physical performance (short physical performance battery score: 10.1 ± 1.8 vs. 10.4 ± 1.1, p = 0.52) and long-distance walking speed (1.2 ± 0.21 vs. 1.3 ± 0.41 m/s, p = 0.17) were similar between the two groups. Self-reported physical function was marginally lower in cases than controls (controls: 72 ± 24 vs. cases: 57 ± 34 AU, p = 0.07). Fatigue disruptiveness was not different between groups (controls: 11.1 ± 13.0 vs. cases: 15.7 ± 16.2 AU, p = 0.24). Similarly, the inflammation, oxidation, and frailty markers did not present a significant difference between groups, except for vitamin D levels (p = 0.04). Conclusion Older women who received chemotherapy reported having slightly lower physical function, but a similar physical performance compared to women who did not. These data suggest that older BCS treated with chemotherapy recover to an extent similar to survivors who only received hormonal therapy.