Higher dialysis adequacy tied to better patient survival

In patients on maintenance haemodialysis (MHD), better dialysis adequacy appears to be an important factor for higher survival, particularly among young patients, reports a recent study.

The study included 558 MHD patients (median age 58 years, 55.6 percent men), in whom dialysis adequacy was expressed as the single-pool Kt/V_urea (spKt/V). Patients were divided into three groups of dialysis adequacy: spKt/V <1.2 (n=155), spKt/V 1.2–1.4 (n=182), and spKt/V >1.4 (n=221). The primary outcome was all-cause mortality, compared across the three patient subgroups.

Kaplan-Meier curves revealed that patient mortality differed significantly across all three spKt/V groups (log-rank p=0.014), such that those in the topmost category had better cumulative survival than the other two subgroups. No such pattern was reported for cardiovascular mortality.

Cox regression analysis confirmed these primary results, showing that patients with spKt/V >1.4 were more than 30 percent less likely to die of all causes than comparators in the lowest dialysis adequacy category (hazard ratio [HR], 0.67, 95 percent confidence interval [CI], 0.47–0.98). A similar effect was reported for cardiovascular mortality, but fell short of statistical significance (HR, 0.68, 95 percent CI, 0.43–1.09).

Of note, stratified analysis according to age showed that high spKt/V was significantly protective against all-cause (HR, 0.46, 95 percent CI, 0.26–0.81) and cardiovascular disease (HR, 0.42, 95 percent CI, 0.20–0.88) mortality in participants aged <65 years. Both endpoints were not significant in older patients.

“Our findings may [help] in developing guidance for dialysis dose in patients on MHD. Future large prospective studies are required to confirm our findings,” the researchers said.