Association between Serum 2-Microglobulin Level and Infectious Mortality in Hemodialysis Patients

Background and objectives: Secondary analysis of the Hemodialysis Study showed that serum 2-microglobulin levels predicted all-cause mortality and that high-flux dialysis was associated with decreased cardiac deaths in hemodialysis patients. This study examined the association of serum 2-microglobulin levels and dialyzer 2-microglobulin kinetics with the two most common causes of deaths: Cardiac and infectious diseases. Cox regression analyses were performed to relate cardiac or infectious deaths to cumulative mean follow-up predialysis serum 2-microglobulin levels while controlling for baseline demographics, comorbidity, residual kidney function, and dialysis-related variables. Results: The cohort of 1813 patients experienced 180 infectious deaths and 315 cardiac deaths. The adjusted hazard ratio for infectious death was 1.21 (95 % confidence interval 1.07 to 1.37) per 10-mg/L increase in 2-microglobulin. This association was independent of the prestudy years on dialysis. In contrast, the association between serum 2-microglobulin level and cardiac death was not statistically significant. In similar regression models, higher cumulative mean Kt/V of 2-microglobulin was not significantly associated with either infectious or cardiac mortality in the full cohort but exhibited trends suggesting a