CD274 and sleep disorder: Further subgroup analysis based on programmed death-ligand 1 (PD-L1) expression level (≥1% vs. <1%) showed that the negative association between sleep disorders and ICI efficacy (CR/PR/SD) was more pronounced in the subgroup with PD-L1 expression < 1% (P = 0.001), while in the PD-L1 expression ≥1% subgroup, the association exhibited a similar trend but did not reach statistical significance (P = 0.186).