Daily step counts to predict hospitalizations during chemoradiotherapy for head and neck cancer.

1571 Background: Wearable activity trackers could provide useful data for managing cancer patients with respect to treatment selection, toxicity monitoring, and implementation of supportive care measures. Here, we seek to evaluate the association between daily step counts and hospitalizations in a cohort of patients with head and neck cancer (HNC). Methods: This analysis consists of patients enrolled in one of three prospective trials involving activity monitoring (NCT02649569, NCT03115398, NCT03102229) during chemoradiation. Study subjects were asked to wear a commercial fitness tracker continuously during the therapy. ECOG performance status (PS) was assessed at baseline, and quality of life (QoL) EORTC QLQ-C30 questionnaires were completed weekly. Multivariable Cox regression models with time-dependent covariates (average step count over the past 3 days, most recent QoL score) and time-fixed covariates (age, sex, baseline PS, study number, baseline tumor volume, and treatment setting [definitive versus postoperative]) were used to identify predictors of first hospital admission during the chemoradiotherapy course. In addition to the Cox regression models, linear mixed models were fitted with daily step count as the dependent variable to examine its relationship with certain independent variables including age, sex, weekend status, days after treatment initiation, and study number. Results: Sixty-six HNC patients who received chemoradiotherapy between 2015 and 2019 were included in the analysis. Median age was 60 (range: 27-88). 47% of patients had ECOG PS score 0, 47% ECOG score 1, and 6% ECOG score 2. 29% of patients had HPV-positive oropharyngeal tumors, and the most common other tumor subsites were larynx (27%), and nasopharynx (12%). The Cox regression survival model demonstrated a 26% reduction in the short-term hospitalization risk for every 1000 daily steps (averaged over the past 3 days, hazard ratio 0.74; 95% confidence interval (CI) 0.55-0.98, p = 0.0367). Hospitalizations were not significantly associated with most recent QoL or baseline ECOG PS. Additionally, according to the linear mixed model results, daily step count was not associated with age (p = 0.8048). Study subjects moved less on weekends (on average 245 fewer steps on weekends than weekdays, 95% CI 134-357, p < 0.0001). Also, an increase in most recently measured ECOG PS was associated with a decrease in daily step count (167 fewer steps for every increase in ECOG PS, 95% CI -289 to -45, p < 0.0072). Conclusions: Daily step counts are a dynamic predictor of hospitalizations in patients undergoing chemoradiotherapy for head and neck cancer. Interventional studies are needed to demonstrate feasibility of leveraging physical activity data to optimize supportive care during cancer therapy and enhance cancer care quality. Clinical trial information: NCT02649569, NCT03115398, NCT03102229.