Protein-energy wasting (PEW) is a leading driver of mortality in maintenance hemodialysis (MHD) patients. Current nutritional assessment relies heavily on serum albumin, a lagging indicator that often masks active nutritional deterioration until stores are significantly depleted. While serum prealbumin offers higher sensitivity, it is frequently dismissed as merely a surrogate for systemic inflammation. It remains unclear whether the longitudinal velocity of prealbumin decline provides prognostic information beyond static markers, average concentration levels, and the acute-phase response.