The effect of frequent hemodialysis on self-reported sleep quality: Frequent Hemodialysis Network Trials

Many patients who receive maintenance hemodialysis experience poor sleep. Uncontrolled studies suggest frequent hemodialysis improves sleep quality, which is a strong motivation for some patients to undertake the treatment. We studied the effects of frequent in-center ('daily') and nocturnal home hemodialysis on self-reported sleep quality in two randomized trials.Participants were randomly assigned to frequent (six times per week) or conventional (three times per week) hemodialysis in the Frequent Hemodialysis Network Daily (n = 245) and Nocturnal (n = 87) Trials. We used the Medical Outcomes Study Sleep Problems Index II (SPI II), a validated and reliable instrument in patients with end-stage renal disease, to measure self-reported sleep quality. The SPI II is scored from 0-100, with a higher value indicating poorer quality of sleep. A mean relative decline in SPI II would suggest improved sleep quality. The primary sleep outcome was the change in the SPI II score over 12 months.In the Daily Trial, after adjustment for baseline SPI II, subjects randomized to frequent as compared with conventional in-center hemodialysis experienced a 4.2 [95% confidence interval (CI) 0.4-8.0] point adjusted mean relative decline in SPI II at 4 months and a 2.6 (95% CI -2.3-7.5) point adjusted mean relative decline at 12 months. In the Nocturnal Trial, subjects randomized to frequent nocturnal as compared with conventional home hemodialysis experienced 2.9 (95% CI -3.4-9.3) and 4.5 (95% CI -3.2-12.2) point mean relative declines at Months 4 and 12, respectively.Although a possible benefit of frequent in-center hemodialysis was observed at 4 months, neither frequent in-center hemodialysis nor home nocturnal hemodialysis demonstrated significant improvements in self-reported sleep quality compared with conventional hemodialysis at 12 months.