Sleep apnea in patients with chronic kidney disease: a single center experience

Figures & data

Table 1. Baseline characteristics of the participants divided by dialysis status.

Variable	Study cohort (mean ± SD)	Dialysis group (mean ± SD)	Non-dialysis group (mean ± SD)	p-Value^a
n	303	101	202
Age (years)	62.7 ± 14.5	60.6 ± 14.4	63.8 ± 14.4	0.07
BMI (kg/m^2)	29.8 ± 6.5	29.4 ± 5.9	30 ± 6.7	0.43
Female gender, n (%)	125 (41.2)	86 (43)	39 (39)	0.50
Diabetes, n (%)	141 (46.7)	53 (52.5)	88 (43.8)	0.15
Smoking, n (%)	28 (9.2)	12 (11.8)	16 (7.9)	0.26
BQ	157 (51.8)	56 (55)	101 (50)	0.37

Notes: BMI: body mass index; BQ: Berlin questionnaire

^ap-Value indicates comparison between the dialysis and non-dialysis groups.

Table 2. Summary of laboratory parameters.

Variable	Study cohort (mean ± SD)	Dialysis group (mean ± SD)	Non-dialysis group (mean ± SD)	p-Value^a
e-GFR (mL/min/1.73 m^2)	21 (7–41)^b	6.2 ± 2.6	36.6 ± 16.3	0.0001
Hb (g/L)	119 ± 22.3	107 ± 20	126 ± 20	0.0001^c
Albumin (g/L)	34.7 ± 4.9	32 ± 5	35.9 ± 4.3	0.0001
PTH (pg/mL)	200 (99–475)^b	635 ± 570	148 ± 118	0.0001^c
Ca^d (mmol/L)	2.2 ± 0.67	2.38 ± 0.18	2.11 ± 0.8	0.88^c
P (mmol/L)	1.4 ± 0.4	1.8 ± 0.5	1.2 ± 0.3	0.0001^c
Glucose (mmol/L)	6.1 (4.9–8.6)^b	8.6 ± 7.5	7.1 ± 3.3	0.3^c

Notes: Ca: calcium; e-GFR: estimated glomerular filtration rate; Hb: hemoglobin; PTH: parathyroid hormone; P: phosphate.

^ap-Value indicates comparison between the dialysis and non-dialysis groups.

^bIndicates median (interquartile range).

^cIndicates Mann–Whitney U-test.

^dIndicates corrected calcium.

Figure 1. Box plot displaying PCS scores in patients with high and low risk for sleep apnea. Note: PCS, physical component summary.

Figure 2. Box plot displaying MCS scores in patients with high and low risk for sleep apnea. Note: MCS, mental component summary.

Table 3. Summary of reduced models for sleep apnea.

Variable^a	Exp (B)	95% CI	p-Value
Age (years)	0.98	0.96–1	0.04
BMI (kg/m^2)	1.06	1.03–1.13	0.001
PCS	0.97	0.94–0.99	0.02
MCS			0.0001
Category 1^b	0.65	0.31–1.35	0.24
Category 2^c	0.38	0.21–0.71	0.002
Category 3^d	0.38	0.21–0.70	0.002

Notes: MCS, mental component summary; PCS, physical component summary.

^aLogistic regression with enter method (p = 0.05) was performed to identify factors independently associated with sleep quality in the study cohort.

^bIndicates comparison of <25% percentile with 25–50% percentile categories.

^cIndicates comparison of 25–50% percentile with 50–75% percentile categories.

^dIndicates comparison of 50–75% percentile with >75% percentile categories.