Abstract

In the Hemodialysis (HEMO) Study, the lower death rate in women but not in men assigned to the higher dose (Kt/V) could have resulted from use of "V" as the normalizing factor, since women have a lower anthropometric V per unit of surface area (V/SA) than men.The effect of Kt/V on mortality was re-examined after normalizing for surface area and expressing dose as surface area normalized standard Kt/V (SAn-stdKt/V).Both men and women in the high-dose group received approximately 16% more dialysis (when expressed as SAn-stdKt/V) than the controls. SAn-stdKt/V clustered into three levels: 2.14/wk for conventional dose women, 2.44/wk for conventional dose men or 2.46/wk for high-dose women, and 2.80/wk for high-dose men. V/SA was associated with the effect of dose assignment on the risk of death; above 20 L/m(2), the mortality hazard ratio = 1.23 (0.99 to 1.53); below 20 L/m(2), hazard ratio = 0.78 (0.65 to 0.95), P = 0.002. Within gender, V/SA did not modify the effect of dose on mortality.When normalized to body surface area rather than V, the dose of dialysis in women in the HEMO Study was substantially lower than in men. The lowest surface-area-normalized dose was received by women randomized to the conventional dose arm, possibly explaining the sex-specific response to dialysis dose. Results are consistent with the hypothesis that when dialysis dose is expressed as Kt/V, women, due to their lower V/SA ratio, require a higher amount than men.

View details for DOI 10.2215/CJN.02350310

View details for Web of Science ID 000281685600015

View details for PubMedID 20595687

View details for PubMedCentralID PMC2974404