Effects of hemodialysis treatment on saliva flow rate and saliva composition during in-center maintenance dialysis: a cross-sectional study

Figures & data

Table 1. Demographics and baseline clinical characteristics of participants prior to receiving hemodialysis for end-stage renal disease (N = 100).

Variable	n (%)	Mean	SD
Demographics
Age, years		62.45	11.09
≤40	3 (3%)
41–65	57 (57%)
≥66	40 (401%)
Gender, male	66 (66%)
Education
<12 years	47 (47%)
≧12 years	53 (53%)
Unemployed	81 (81%)
Married, yes	78 (78%)
Religious, yes	90 (90%)
Exercise ≧ 3 times per week, yes	30 (30%)
Frequency of teeth brushing in a day
Once, after waking up in the morning 21 (21%)
Once, before going to sleep at night 4 (4%)
Twice, in the morning and at night 65 (65%)
Three times or more 4 (4%)
Do not brush teeth and other oral hygiene habits 6 (6%)
Brush teeth for more than 3 min, yes 50 (50%)
Gargle after meal, yes 67 (67%)
Frequency of changing toothbrush
One mouth 15 (15%)
Two mouth 15 (15%)
More than three mouths 19 (19%)
When the bristles are splayed 46 (46%)
Other 5 (5%)
Brush pattern
Bass method	1 (1%)
Horizontally brushing	29 (29%)
Fones method	47 (47%)
Physiology brushing	9 (9%)
Brush at will	3 (3%)
Other	11 (11%)
See a dentist in the past year, yes	34 (34%)
Clinical characteristics
Smoker, yes	13 (13%)
Duration of hemodialysis (years)		5.10	4.96
Comorbidity
Hypertension	67 (67%)
Other	55 (55%)
Systolic blood pressure, mm HG		143.85	18.98
Diastolic blood pressure, mm Hg		77.65	10.13
Serum components
White blood cells, per uL		6.63	1.99
Red blood cells, per uL		3.67	0.50
Hemoglobin, g/dL		10.91	0.96
Hematocrit, %		32.55	2.83
Mean corpuscle volume		89.53	8.30
Mean corpuscular hemoglobin conc.		33.53	1.12
Platelets		171.98	62.03
Kt/v		1.48	0.17
GOT (u/L)		21.15	8.99
GPT (u/L)		18.88	12.30
Alkaline phosphatase		316.66	170.53
Albumin, g/dL		3.94	0.19
Blood urea nitrogen, mg/dL		67.99	14.35
Creatinine, mg/dL		9.63	1.68
Blood glucose (A1C), mg/dL		216.12	96.79
Electrolytes
Na, mEq/L		136.07	3.46
K, mEq/L		4.63	0.67
Ca, mEq/L		8.98	0.92
K, mEq/L		4.61	1.19

SD: standard deviation.

Table 2. Comparison of saliva variables before (pre-dialysis), during (mid-dialysis), and 1 h after completion of dialysis (post-dialysis) for participants (N = 100).

	Time of sampling
	Pre-dialysis (T1)	Mid-dialysis (T2)	Post-dialysis (T3)			Comparison
Saliva variables	Mean ± SD	Mean ± SD	Mean ± SD	Wald χ^2	p	Post-hoc
Saliva flow rate, ml/min	0.15 ± 0.10	0.17 ± 0.13	0.19 ± 0.12	10.40**	.006	3 > 1
Biochemicals, mg/L
BUN	57.29 ± 38.87	32.89 ± 22.35	24.97 ± 17.94	97.12***	<.001	3 < 2 < 1
Cr	0.80 ± 0.80	0.47 ± 0.86	0.31 ± 0.45	36.98***	<.001	2 < 1; 3 < 1
pH	7.83 ± 0.75	7.63 ± 0.68	7.30 ± 0.83	30.13***	<.001	3 < 2 < 1
Osmolality	257.59 ± 280.31	247.57 ± 379.46	170.81 ± 207.74	9.71**	.008	3 < 1; 3 < 2
Electrolytes, mEq/L
Na	40.84 ± 32.78	38.71 ± 32.47	34.59 ± 31.88	3.69	.158
K	25.79 ± 14.48	22.23 ± 13.17	22.86 ± 11.85	6.71*	.035	2 < 1; 1 > 3
Cl	53.36 ± 26.47	45.55 ± 27.39	41.09 ± 27.56	17.64***	<.001	1 > 2; 1 > 3
Ca	4.16 ± 3.46	4.26 ± 3.76	5.50 ± 4.02	12.73**	.002	3 > 1; 3 > 2

SD: standard deviation. *p < .05, **p < .01, ***p < .001.

Table 3. Differences in saliva flow rate by interdialytic weight gain (IDWG).

	IDWG/dry weight
	<5% (n = 85)	≧5% (n = 15)
	Mean ± SD	Mean ± SD	t	p
Pre-dialysis (T1)	.15	.14	.25	.80
Mid-dialysis (T2)	.18	.13	2.11	.04*
Post-dialysis (T3)	.20	.14	2.53	.02*

Figure 1. Participants’ changes in pH at each time point Participants’ changes in osmo at each time point.

Figure 2. Participants’ changes in sodium at each time point Participants’ changes in potassium at each time point.

Figure 3. Participants’ changes in chloride at each time point Participants’ changes in calcium at each time point.

Figure 4. Participants’ changes in potassium at each time point.

Figure 5. Participants’ changes in chloride at each time point.

Figure 6. Participants’ changes in calcium at each time point.