The association of health-care contact days with physical function and survival in CCTG/AGITG CO.17

Introduction: Although contact days—days with health-care contact outside home—are increasingly adopted as a measure of time toxicity and treatment burden, they could also serve as a surrogate of treatment-related harm. We sought to assess the association between contact days and patient-reported outcomes and the prognostic ability of contact days. 

Methods: We conducted a secondary analysis of CO.17 that evaluated cetuximab vs supportive care in patients with advanced colorectal cancer. CO.17 collected European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 instrument data. We assessed the association between number of contact days in a window and changes in physical function and global health status and the association between number of contact days in the first 4 weeks with overall survival. 

Results: There was a negative association between the number of contact days and change in physical function (per each additional contact day: at 4 weeks, 1.50-point decrease; 8 weeks, 1.06-point decrease; P < .0001 for both) but not with global health status. This negative association was seen in patients receiving cetuximab but not supportive care. More contact days in the first 4 weeks was associated with worse overall survival for all participants and patients receiving cetuximab (per each additional contact day: all participants, adjusted hazard ratio [HR] = 1.07, 95% confidence interval [CI] = 1.05 to 1.10; and cetuximab, adjusted HR = 1.08, 95% CI = 1.05 to 1.11; P < .0001 for both). 

Conclusions: In this secondary analysis of a clinical trial, more contact days early in the course were associated with declines in physical function and worse survival in all participants and in participants receiving cancer-directed treatment.