Self-assessed sleep quality in chronic kidney disease.

BACKGROUND

Although sleep complaints are commonly reported in persons with end stage renal disease (ESRD), little is known about the prevalence of sleep complaints in chronic kidney disease (CKD), and the relation of sleep quality to the severity of kidney disease.

METHODS

We administered the Kidney Disease Quality of Life (KDQOL) sleep scale to 156 subjects, 78 with ESRD and 78 with CKD. Glomerular filtration rate (GFR) was estimated using the six variable Modification of Diet in Renal Disease (MDRD) equation and used to stratify subjects with CKD as mild-moderate (GFR >25 ml/min/1.73 m(2)) and advanced (GFR <25 ml/min/1.73 m(2)). We used multivariable linear regression to determine independent predictors of KDQOL sleep scale scores. Higher scores indicate higher self-reported quality of sleep.

RESULTS

Median scores on the KDQOL sleep scale were 59 (interquartile range 40-80) in subjects with ESRD and 69 (interquartile range 53-80) in subjects with CKD (P=0.04). Thirty-four percent of subjects with ESRD, 27% of subjects with advanced CKD, and 14% of subjects with mild to moderate CKD had sleep maintenance disturbances (P=0.05). Thirteen percent of subjects with ESRD, 11% of subjects with advanced CKD, and no subjects with mild-moderate CKD had complaints of daytime somnolence (P=0.03). There was no significant difference in the prevalence of sleep adequacy complaints in persons with ESRD versus CKD. In multivariable analyses, only age and ESRD status (vs. CKD) were significant predictors of lower KDQOL sleep scores. Among subjects with CKD, there was a significant direct association between estimated GFR and scores on the KDQOL sleep scale in non-African American subjects (P=0.01).

CONCLUSIONS

Sleep complaints are common in persons with CKD and ESRD and may be associated with the severity of kidney disease.