Cognitive impairment is common among patients with end-stage renal disease receiving hemodialysis 3x-per-week.
Randomized Clinical Trial
Setting & Participants
218 subjects participating in the Frequent Hemodialysis Network (FHN) Daily Trial and 81 subjects participating in the FHN Nocturnal Trial.
The Daily Trial tested in-center hemodialysis 6x-per-week versus 3x-per-week. The Nocturnal Trial tested home nocturnal hemodialysis 6x-per-week versus home or in-center hemodialysis 3x-per-week.
Cognitive function was measured at baseline, month four, and month 12. The primary outcome was performance on the Trail-Making Test, Form B, a measure of executive function, and a secondary outcome was performance on the Modified Mini-Mental State Examination, a measure of global cognition. The domains of attention, psychomotor speed, memory and verbal fluency were assessed in 59 participants in the Daily Trial and 19 participants in the Nocturnal Trial.
We found no benefit of frequent hemodialysis in either trial for the primary cognitive outcome (Daily Trial: OR for improvement, 0.99; 95% CI, 0.59–1.66; Nocturnal Trial: OR, 1.19; 95% CI, 0.48–2.96). Similarly, there was no benefit of frequent hemodialysis in either trial on global cognition, the secondary cognitive outcome. Exploratory analyses in the Daily Trial suggested possible benefits of frequent hemodialysis on memory and verbal fluency, but not on attention and psychomotor speed. Exploratory analyses in the Nocturnal Trial suggested no benefit of frequent hemodialysis on attention, psychomotor speed, memory, or verbal fluency.
Unblinded intervention, small sample
Frequent hemodialysis did not improve executive function or global cognition.