Removal of uremic toxins by hemodialysis improves cognitive function, data suggest.
Researchers studied 15 patients with end-stage renal disease (ESRD) who were on maintenance hemodialysis for at least one month. They evaluated cognitive function two hours before and two hours after undergoing hemodialysis. The findings were compared with an age- and sex-matched group of healthy controls.
The investigators, led by Pankaj Madan, MD, of the Baylor College of Medicine in Houston, assessed P3 latency, which corresponds to the speed of cognitive processing and memory. It is measured in milliseconds (ms) using an apparatus that measures electrophysiological activity in the brain.
Before hemodialysis, patients’ P3 latency was significantly increased compared with that of the healthy controls (347.72 vs. 308.4 ms). After hemodialysis, patients’ P3 latency had decreased significantly to 325.20 ms, which was not significantly different from that of controls, the authors reported in Renal Failure (2007;29:699-703).
Dr. Madan’s group found no correlation between various biochemical parameters (hemoglobin, blood urea, creatinine, uric acid, and calcium) and improvement in cognitive function. Thus, hemodialysis probably improves cognitive function in ESRD patients through the removal of