Nerve conduction studies and prediction of mortality in hemodialysis patients

The electrophysiological aspects of uremic neuropathy have been studied extensively, but never for prediction of mortality. In order to assess the parameters of nerve conduction study (NCS) as predictors of mortality in hemodialysis patients, a post hoc analysis of a prospective observation study was made.

We examined conventional electrophysiological parameters (motor nerve conduction velocity [MCV], terminal latency [TL], and F wave latency of the peroneal nerve, as well as sensory nerve conduction velocity [SCV] of the sural nerve) in 75 nondiabetic patients. Hemodialysis modality (bicarbonate dialysis and biocompatible membranes), Kt/V, comorbidity (ischemic heart disease and congestive heart failure), and clinical and laboratory parameters were also evaluated. Survival was analyzed using the Cox proportional hazard model.

SCV was significantly higher (t-test, p < 0.01) in the group of patients treated with polysulfone compared to those using cuprophane membranes. On the other hand, MCV significantly correlated with Kt/V (Pearson, r = 0.388; p < 0.01). Multivariate Cox regression revealed only MCV as a significant predictor of mortality in this group of hemodialysis patients (HR = 0.92; CI (0.86-0.99); p < 0.05).

Only MCV was a significant mortality risk predictor among NCS parameters. This parameter correlates significantly with dialysis dose. SCV was related to the use of biocompatible membranes, indicating the complexity of polyneuropathy in dialysis patients.