Physical activity trajectories and associated factors in patients with lung cancer undergoing chemotherapy: A...

To characterize heterogeneity in physical activity (PA) trajectories among patients with lung cancer during early chemotherapy and examine associated demographic, clinical, and psychosocial factors.

This longitudinal study enrolled 155 patients initiating chemotherapy at the First Affiliated Hospital of Anhui Medical University in Anhui Province, China. PA was assessed using the International Physical Activity Questionnaire-Short Form at baseline and before the second, third, and fourth cycles. Symptom burden, exercise self-efficacy, outcome expectations for exercise, and social support were assessed exclusively at baseline. Latent class growth analysis was utilized to identify PA trajectories. Factors associated with trajectory membership were analyzed using a two-stage strategy combining least absolute shrinkage and selection operator regression and Firth's penalized logistic regression.

Among 122 completers, two distinct trajectories were identified. The majority (77.9%) followed a "Moderate-Sustained Decline" trajectory, showing a significant drop at cycle 2 with persistently low activity. Conversely, 22.1% exhibited a "High-Decline-Partial Recovery" trajectory, characterized by a behavioral rebound after the initial decline. Multivariate analysis revealed that higher symptom burden (OR = 1.105, P = 0.028) and more pessimistic outcome expectations (OR = 1.723, P = 0.005) increased the likelihood of sustained decline. Higher exercise self-efficacy (OR = 0.855, P = 0.003) was significantly associated with the partial recovery profile.

PA patterns are heterogeneous, though a decline prior to the second cycle is universal. Lower symptom burden and stronger cognitive resources may support more favorable physical activity trajectories. Proactive nursing interventions integrating symptom management with cognitive-behavioral empowerment targeting the critical window before the second cycle are recommended to prevent functional decline.