Table 1.

Patient characteristics by different chronic kidney disease (CKD) stages.

Variable	Stage 1 (n = 19)	Stage 2 (n = 26)	Stage 3 (n = 38)	Stage 4 (n = 21)	Stage 5 (n = 17)	All (n = 121)	p-Value
Age (year)	49.4 ± 4.1	58.3 ± 2.3	66.4 ± 2.3	66.4 ± 3.2	66.0 ± 3.6	61.9 ± 1.4	<0.001
Male (%)	8 (42.1%)	16 (61.5%)	19 (50%)	11 (52.4%)	8 (47.1%)	62 (51.2%)	0.756
Body weight (Kg)	68.2 ± 3.4	70.1 ± 3.0	63.2 ± 1.7	64.3 ± 2.6	60.2 ± 2.0	65.3 ± 1.1	0.067
Hemoglobin (g/mL)	12.8 ± 0.7	14.9 ± 0.4	15.4 ± 1.6	13.9 ± 1.6	9.8 ± 0.3	13.8 ± 0.7	0.089
Albumin (g/dL)	4.29 ± 0.16	4.19 ± 0.11	4.19 ± 0.08	4.04 ± 0.09	3.99 ± 0.09	4.12 ± 0.04	0.251
BUN (mg/dL)	15.6 ± 1.9	17.7 ± 1.1	24.4 ± 1.6	42.6 ± 2.5	85.1 ± 7.5	38.7 ± 3.1	<0.001
Creatinine (mg/dL)	0.65 ± 0.03	0.95 ± 0.04	1.34 ± 0.04	2.87 ± 0.12	6.46 ± 0.50	2.13 ± 0.19	<0.001
eGFR (mL/min)	116 ± 5.7	75 ± 1.4	48 ± 1.3	20 ± 1.0	9 ± 0.6	54 ± 3.3	<0.001
Breath ammonia (ppb)	636 ± 94	1020 ± 120	1943 ± 326	4421 ± 1042	12781 ± 1807	3493 ± 484	<0.001
Salivary pH	6.52 ± 2.68	6.84 ± 0.50	7.13 ± 0.54	7.61 ± 0.48	8.10 ± 0.41	7.21 ± 0.68	<0.001
Comorbidity
CHF	0 (0%)	1 (3.8%)	1 (2.6%)	1 (4.8%)	0 (0%)	3 (2.5%)	0.814
CAD	1 (5.3%)	2 (7.7%)	4 (10.5%)	0 (0%)	4 (23.5%)	11 (9.1%)	0.142
HTN	8 (42.1%)	21 (80.8%)	28 (73.7%)	19 (90.5%)	12 (70.6%)	8 (72.7%)	0.010
DM	7 (36.8%)	11 (40.7%)	13 (34.2%)	9 (42.9%)	6 (35.3%)	46 (38.0%)	0.950
Medication
Steroids	6 (31.6%)	3 (11.5%)	5 (13.2%)	3 (14.3%)	2 (11.8%)	19 (15.7%)	0.358
ACEi/ARB	8 (42.1%)	20 (76.9%)	21 (55.3%)	10 (47.6%)	6 (35.3%)	65 (53.7%)	0.053
PPI use	0 (0%)	0 (0%)	2 (5.3%)	0 (0%)	1 (5.9%)	3 (2.5%)	0.447

CKD, chronic kidney disease; BUN, blood urea nitrogen; CHF, congestive heart failure; CAD, coronary heart disease; DM, diabetes mellitus; eGFR, estimated glomerular filtration rate; ACEi, angiotensin converting enzyme inhibitor; ARB, angiotensin receptor II blocker; PPI, proton pump inhibitor.