Both too little and too much sleep is associated with low health-related quality of life (HRQOL) for patients with pre-dialysis chronic kidney disease (CKD), according to new study findings published in the Clinical Journal of the American Society of Nephrology.
Kyu-Beck Lee, MD, of Sungkyunkwan University School of Medicine in Seoul, South Korea, and colleagues studied sleep duration in 1910 adults from KNOW-CKD (Korean Cohort Study for Outcome in Patients with CKD). Of these, 11% of participants were short sleepers and 7% were long sleepers. Patients with advanced CKD tended to sleep longer.
The team found an inverted U-shaped relationship between sleep duration and HRQOL. CKD patients who slept 7 hours nightly had the highest HRQOL, based on both mental and physical component scores on the Short Form-36 Health Survey. Those who slept 5 or fewer hours or 9 or more hours had lower HRQOL.
“Kidney physiology is modulated by the sleep-wake cycle, including molecular expression of nephrons, sodium reabsorption, and glomerular filtration,” Dr Lee and colleagues explained. “Thus, disturbance of sleep and kidney function can have adverse effects on each other.”
The authors noted that sleep disorders, such as insomnia, restless leg syndrome, periodic limb movements, and sleep apnea, are common in patients with CKD, and especially those with end-stage renal disease.
Previous research has linked poor sleep with adverse cardiometabolic risk and mortality. The authors suggested future studies should investigate whether improving sleep increases HRQOL and other outcomes in CKD patients.
Sung SA, Hyun YY, Beck Lee K, et al. Sleep duration and health-related quality of life in predialysis CKD—KNOW-CKD study. Clin J Am Soc Nephrol. doi: 10.2215/CJN.11351017 [Published May 3, 2018].