In the fully adjusted model (Model 3), which included dialysis duration, diabetes mellitus, cardiovascular disease, smoking status, serum creatinine, hemoglobin, GNRI, Kt/V, and CRP, PA remained independently associated with SF-36 physical functioning (β = 8.31, p < 0.001), role—physical (β = 8.46, p = 0.020), general health (β = 4.52, p = 0.006), and the KDQOL-SF work status domain (β = 8.37, p = 0.023). Here, CRP is linked to diabetes mellitus.