Relationships between T-lymphocytes and physical function in adults with chronic lymphocytic leukemia: Results from the HEALTH4CLL pilot study

Objective: Examine physical function and T-cell phenotype in patients with chronic lymphocytic leukemia (CLL) before and after a physical activity (PA) intervention. Methods: Physical function measures and blood samples were collected from CLL patients (Rai stage 0–4, 50% receiving targeted therapy, N = 24) enrolled in a 16-week intervention of at-home aerobic and/or resistance exercise. Flow cytometry characterized T-cells in cryopreserved peripheral blood cells. Wilcoxon signed-rank test compared physical function and T-cell phenotype at baseline and 16-weeks; Kendall's Tau assessed associations between variables. Results: Godin leisure-time PA score increased from baseline to 16-weeks (mean difference: 14.61, p <.01) and fatigue decreased (mean difference: 6.71, p <.001). At baseline, lower fatigue correlated with a lower proportion of CD8+ T-cells (τ = 0.32, p =.03) and cardiorespiratory fitness (CRF) inversely correlated with the percentage of PD-1+CD8+ T-cells (τ −0.31, p =.03). At 16-weeks, CRF inversely correlated with the proportion of PD-1+CD4+ T-cells (τ −0.34, p =.02). Reduced fatigue at 16-weeks correlated with an increased CD4:CD8 ratio (τ = 0.36, p =.02) and lower percentage of HLA-DR+PD-1+CD4+ T-cells (τ = −0.37, p =.01). Conclusions: This intervention increased leisure-time PA and decreased fatigue in CLL patients. These changes correlated with an increased CD4:CD8 T-cell ratio and reduced proportion of T-cells subsets previously associated with poor outcomes in CLL patients. Trial registration: ClinicalTrials.gov Identifier: NCT02194387.