A pilot study of an accelerometer-equipped smartphone to monitor older adults with cancer receiving chemotherapy in Mexico

Objectives: Older adults with cancer in developing countries face challenges accessing healthcare due to a lack of personnel and infrastructure. A decline in physical activity (defined as a decrease in the number of daily steps) may be a novel method for the timely detection of toxicity in older adults receiving chemotherapy in resource-constrained settings.

Materials and methods: In this feasibility study, patients aged ≥65years starting first-line chemotherapy for solid tumors were given a smartphone with a pedometer application. Daily steps were monitored daily for one cycle. If a ≥15% decrease from baseline was identified, the patient was called and the presence of toxicity assessed. The intervention would be feasible if ≥75% of the subjects recorded steps for ≥75% of the planned chemotherapy days.

Results: Forty patients (median age 73; 57% [N=23] female) were included. Seventy percent (N=28) had stage III-IV disease with 45% (N=18) gastrointestinal, 23% (N=9) breast, and 32% (N=13) other malignancies. Mean pre-treatment daily steps was 3111 (Standard Deviation [SD] 1731), and median follow-up was 21days (range 2-28). Despite having limited exposure to mobile technology, most (93%) patients used the smartphone appropriately, and 85% found it easy to use. Sixty percent of patients (N=24) had toxicities managed over the phone, 27.5% (N=10) were sent for urgent medical attention and 15% (N=6) were hospitalized.

Conclusion: Using smartphones to monitor older adults with cancer receiving chemotherapy in a resource-constrained setting is feasible and acceptable. A decrease in the number of daily steps was common and helped to identify chemotherapy toxicity.