Hong WP, et al. - By performing a retrospective review of data from the Korean Society of Nephrology registry, researchers examined the link between hemodialysis (HD) adequacy and mortality by body mass index (BMI) in HD patients, as well as focused on a combined impact of BMI and HD adequacy on mortality risk. Participants were patients ≥ 18 years old on maintenance HD. As per baseline BMI, these were divided into < 20 (low), 20 to < 23 (normal), and ≥ 23 (high) kg/m² groups. In Cox regression analysis, the link of lower and higher baseline single-pool Kt/V_urea (spKt/V) with greater and lower risks for all-cause mortality, respectively, was observed, compared with the reference (spKt/V 1.2–1.4). However, all adjusted models showed an attenuated link between higher spKt/V and lower all-cause mortality in patients with high BMI (n = 5,588). At all spKt/V levels, a higher risk for all-cause mortality was observed in those with low BMI vs those with normal BMI and spKt/V within the target range (1.2–1.4). For higher values of spKt/V, the gap in death risk became narrower. No increased risk for mortality was evident despite low dialysis adequacy in patients with high BMI and spKt/V < 1.2 vs those with normal BMI and spKt/V in the target range. Experts concluded BMI as a possible modifier of the link between spKt/V and mortality in HD patients.