Acoustic Characteristics of Voice in Patients with Chronic Kidney Disease

Figures & data

Figure 1 Sex of participants.

Figure 2 Age of participants.

Abbreviation: SD, Standard deviation.

Table 1 Comparisons Among Control (n=20), HD (n= 20), and CKD (n=20) groups on Hemoglobin, Uric Acid, HCO₃, eGFR, Urea-Reduction Ratio, Urea, and Creatinine

		Control	HD	CKD	µ*	P	Post hoc Analysis
		n=20	n=20	n=20			P1	P2	P3
Hemoglobin	Mean ± SD	11.93±0.73	9.78±1.35	10.60±1.60	13.719	0	0	0.002	0.098
	Range	10.5–13	8–12	8–13
Uric acid	Mean ± SD	3.77±0.60	6.80±0.77	7.10±0.79	129.715	0	0	0	0.230
	Range	3–5	6–8	6–8
HCO3	Mean ± SD	23.20±1.32	18.60±1.31	16.95±1.85	91.329	0	0	0	0.002
	Range	21–26	16–20	14–20
eGFR	Mean ± SD	116.25±18.81	8.10±2.95	31.60±5.51	494.045	0	0	0	0
	Range	79–142	5–12	23–40
Urea-reduction ratio	Mean± SD	—	64.60±6.84	—	NA	NA
	Range	—	55–76	—
Urea	Mean ± SD	32.45±6.37	177.30±20.09	110.30±13.80	496.621	0	0	0	0
	Range	23–41	140–200	96–135
Creatinine	Mean ± SD	0.88±0.18	8.80±0.89	3.42±1.38	358.480	0	0	0	0
	Range	0.5–1.2	8–11	1.3–6

Notes: *One-way ANOVA; P₁, control vs HD; P₂, control vs CKD; P₃, HD vs CKD.

Abbreviation: eGFR, estimated glomerular filtration rate.

Table 2 Comparisons Among Control (n=20), HD (n= 20), and CKD (n=20) Groups on Respiratory Function Tests

		Control	HD	CKD	µ*	P	Post hoc Analysis
		n=20	n=20	n=20			P1	P2	P3
Expiratory time (seconds)	Mean ± SD	3.21±1.01	3.24±0.49	3.35±0.65	0.194	0.825	0.907	0.606	0.550
	Range	1.5–4.5	2.4–4	3–5
VC	Mean ± SD	106.50±11.98	57.70±14.66	67.30±13.39	74.559	0	0	0	0.037
	Range	93–125	47–85	55–87
FVC	Mean ± SD	94.30±7.89	55.90±14.48	62.40±11.93	61.165	0	0	0	0.130
	Range	83–112	45–83	45–85
FEV1	Mean ± SD	97.55±8.38	60.40±15.49	70.60±12.16	48.283	0	0	0	0.026
	Range	83–112	49–90	50–84
FEV1/FVC	Mean ± SD	1.04±0.12	1.12±0.31	1.20±0.10	1.296	0	0.030	0.010	0.777
	Range	0.77–1.32	0.69–1.96	0.99–1.28
FEF25%	Mean ± SD	7.32±0.98	63.40±1.67	64.50±3.15	4,690.336	0	0	0	0.176
	Range	5.82–8.56	60–65	60–69
FEF75%	Mean ± SD	2.79±0.57	63.40±1.39	63.70±1.38	17,731.312	0	0	0	0.498
	Range	1.62–3.42	62–65	62–65

Notes: *One-way ANOVA; P₁, control vs HD; P₂, control vs CKD; P₃, HD vs CKD.

Abbreviations: FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; FEF, forced expiratory flow.

Table 3 Comparisons Among Control (n=20), HD (n= 20), and CKD (n=20) Groups on Acoustic Parameters

		Control	HD	CKD	µ*	P	Post hoc snalysis
		n=20	n=20	n=20			P1	P2	P3
Fundamental frequency	Mean ± SD	144.15±47.14	177.02±35.77	174.23±37.74	4.046	0.013	0.018	0.032	0.812
	Range	98–213	135.2–225.7	127.9–216.8
Shimmer percentage	Mean ± SD	0.63±0.13	2.40±0.59	2.67±0.64	93.492	0	0	0	0.176
	Range	0.5–0.99	1.84–3.75	1.95–3.4
Jitter percentage	Mean ± SD	2.00±0.61	1.10±1.12	1.43±0.81	3.732	0	0	0.017	0.641
	Range	0.55–2.8	0.43–3.98	0.39–2.77
Harmonic:noise ratio	Mean ± SD	7.80±0.23	6.29±1.22	6.87±0.40	20.544	0	0	0	0.050
	Range	7.4–8.2	3.7–7.3	6.2–7.4

Notes: *One-way ANOVA; P₁, control vs HD; P₂, control vs CKD; P₃, HD vs CKD.

Abbreviation: CKD, chronic kidney disease.

Table 4 Correlations between duration of HD and demographic data, laboratory tests, respiratory function tests, and acoustic parameters

	Duration of HD
	R	P
Age	−0.415	0.069
Hb	−0.178	0.479
Uric acid	0.362	0.117
HCO3	−0.602*	0.005
eGFR	−0.362	0.117
Urea-reduction ratio	0.266	0.257
Urea	−0.310	0.184
Creatinine	−0.311	0.182
Expiratory time (seconds)	−0.275	0.241
VC	−0.579*	0.007
FVC	−0.576*	0.008
FEV1	−0.511*	0.021
FEV1/FVC	−0.019	0.936
FEF25%	−0.334	0.151
FEF75%	−0.123	0.605
Fundamental frequency	0.066	0.783
Shimmer percentage	−0.781*	0
Jitter percentage	−0.823*	0
Harmonic:noise ratio	0.850*	0

Note: *P<0.05.

Abbreviations: Hb, hemoglobin; eGFR, estimated glomerular filtration rate; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; FEF, forced expiratory flow.

Table 5 Correlations Between Laboratory Tests and Respiratory Function Tests Against Acoustic Parameters in the HD Group

	Fundamental Frequency		Shimmer Percentage		Jitter Percentage		Harmonic:Noise Ratio
	r	P	r	P	r	P	r	P
Hb	0.369	0.132	−0.073	0.773	0.153	0.544	−0.044	0.863
Uric acid	−0.242	0.303	−0.156	0.512	−0.107	0.654	0.278	0.235
HCO3	0.191	0.421	0.365	0.114	0.394	0.085	−0.403	0.078
eGFR	−0.129	0.588	0.323	0.165	0.217	0.357	−0.297	0.203
Urea-reduction ratio	0.202	0.394	−0.127	0.593	0.078	0.745	−0.032	0.893
Urea	−0.255	0.278	0.347	0.134	0.383	0.095	−0.250	0.288
Creatinine	0.638*	0.002	0.539*	0.014	0.613*	0.004	−0.455*	0.044
Expiratory time (seconds)	0.423	0.063	0.181	0.444	0.502*	0.024	−0.217	0.357
VC	0.369	0.110	0.416	0.068	0.694*	0.001	−0.469*	0.037
FVC	0.364	0.114	0.409	0.073	0.693*	0.001	−0.462*	0.040
FEV1	0.170	0.475	0.658*	0.002	0.836*	0	−0.827*	0
FEV1/FVC	−0.283	0.227	0.216	0.362	0.198	0.403	−0.383	0.096
FEF25%	−0.121	0.611	0.567*	0.009	0.438	0.053	−0.510*	0.022
FEF75%	0.015	0.951	0.435	0.055	0.384	0.095	−0.443	0.050

Note: *P<0.05.

Abbreviations: Hb, hemoglobin; CKD, chronic kidney disease; eGFR, estimated glomerular filtration rate; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; FEF, forced expiratory flow.

Table 6 Correlations between Laboratory Tests and Respiratory Function Tests Against Acoustic Parameters in the CKD Group

	Fundamental Frequency		Shimmer Percentage		Jitter Percentage		Harmonic:Noise Ratio
	r	P	r	P	r	P	r	P
Hb	0.021	0.930	−0.144	0.545	−0.084	0.725	0.660*	0.002
Uric acid	0.051	0.830	0.319	0.171	0.061	0.798	−0.072	0.763
HCO3	−0.514*	0.020	−0.121	0.612	−0.355	0.124	−0.248	0.292
eGFR	0.165	0.486	−0.357	0.122	−0.197	0.404	0.731*	0
Urea	−0.054	0.820	−0.141	0.553	0.238	0.311	−0.716*	0
Creatinine	0.079	0.742	−0.372	0.106	−0.139	0.560	−0.666*	0.001
Expiratory time (seconds)	−0.362	0.117	−0.122	0.609	−0.468*	0.037	0.162	0.495
VC	−0.272	0.245	0.418	0.067	−0.131	0.582	0.376	0.103
FVC	−0.323	0.165	0.152	0.523	−0.159	0.503	0.521*	0.019
FEV1	−0.277	0.237	0.423	0.063	0.046	0.846	0.510*	0.022
FEV1/FVC	0.051	0.832	0.391	0.088	0.315	0.176	−0.071	0.766
FEF25%	−0.195	0.411	−0.098	0.682	0.073	0.759	0.017	0.943
FEF75%	0.191	0.421	−0.488*	0.029	−0.503*	0.024	0.113	0.636

Note: *P<0.05.

Abbreviations: Hb, hemoglobin; eGFR, estimated glomerular filtration rate; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; FEF, forced expiratory flow.

Table 7 Linear Regression for Predictors of Changes of Acoustic Parameters

	Fundamental Frequency		Jitter Percentage		Shimmer Percentage		Harmonic:Noise Ratio
	Unstandardized β Coefficient	P	Unstandardized β Coefficient	P	Unstandardized β Coefficient	P	Unstandardized β coefficient	P
Hb	−52.236	0*	0.488	0*			0.404	0*
Uric acid	−27.697	0*	0.888	0*	0.829	0*
HCO3			0.437	0*			−0.162	0*
eGFR	3.411	0*			−0.200	0*	−0.077	0*
Urea-reduction ratio	4.597	0*	0.058	0*	−0.105	0*
Urea	−2.702	0*			−0.008	0*
Creatinine			0.912	0*			−0.347	0*
Expiratory time (seconds)	43.650	0*	−1.690	0*	−0.273	0*
VC			0.045	0*
FVC	2.630	0*			−0.040	0*	−0.025	0*
FEV1
FEV1/FVC					0.285	0*	−0.082	0*
FEF25%			0.114	0*			−0.089	0.002*
FEF75%					−0.414	0*	0.211	0.001*
Constant	−752.85	0*	−26.559	0*	11.297	0*	9.915	0.015*

Note: *P<0.05.

Abbreviations: Hb, hemoglobin; eGFR, estimated glomerular filtration rate; FEV₁, forced expiratory volume in 1 second; FVC, forced vital capacity; FEF, forced expiratory flow.