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<0.01) and fatigue decreased (mean difference: 6.71, p<0.001). At baseline, lower fatigue correlated with a lower proportion of CD8+T-cells (τ= 0.32, p=0.03) and cardiorespiratory fitness (CRF) inversely correlated with the percentage of PD-1+CD8+T-cells (τ -0.31, p=0.03). At 16-weeks, CRF inversely correlated with the proportion of PD-1+CD4+T-cells (τ -0.34, p=0.02). Reduced fatigue at 16-weeks correlated with an increased CD4:CD8 ratio (τ=0.36, p=0.02) and lower percentage of HLA-DR+PD-1+ CD4+ T-cells (τ =-0.37, p=0.01).

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.