Cervical Interferential Current Transcutaneous Electrical Sensory Stimulation for Patients with Dysphagia and Dementia in Nursing Homes

Figures & data

Figure 1 Participant flowchart.

Figure 2 Positions of electrodes. The upper electrodes are placed directly below the mandibular angle, and the lower electrodes are placed at the level of the thyroid cartilage along the anterior edge of the sternocleidomastoid muscle. A 50-beat interferential wave is generated from two different alternating currents (2000 or 2500 Hz).

Table 1 Baseline Characteristics of the Patients

Characteristics	Total (n = 54)
Age (years)	84.5±10.7
Female, n (%)	41 (75.9)
Male, n (%)	13 (24.1)
BMI (kg/m^2)	20.5±3.0
MNA	19.7+3.9
BI score	36.2±29.0
MMSE score	11.4±9.1
Comorbidities, n (%)
Stroke	21 (38.9)
Cognitive disorder	15 (27.8)
Parkinson disease	3 (5.6)
Head and neck disease	5 (9.2)
Others	10 (18.5)

Note: Data are given as mean±SD or n (%).

Abbreviations: BI, Barthel index; BMI, body mass index; MMSE, mini-mental state examination; MNA, mini nutritional assessment; SD, standard deviation.

Table 2 Outcome Comparisons of Cough Reflex and Nutritional Intake Before and After the 3-Week IFC-TESS

	Before (n = 54)	After 3 Weeks (n = 54)	p-value	Effect Size
Cough latency (s)	15.8 (7.0–60.0)	6.7 (3.6–30.7)	<0.001^a	0.469
Cough frequency (n/min)	5.0 (0.0–5.0)	5.0 (5.0–5.0)	0.001^a	0.507
FOIS score	5.0 (5.0–6.0)	5.0 (5.0–6.0)	0.020^a	0.156
Nutritional oral intake (kcal/day)	1300.0 (862.5–1420.0)	1300.0 (1005.0–1462.5)	<0.001^a	0.235

Note: Data are given as median (IQR) for Wilcoxon signed-rank test. ^aStatistically significant.

Abbreviations: FOIS, functional oral intake scale; IFC-TESS, interferential current transcutaneous electrical sensory stimulation; IQR, interquartile range.

Table 3 Comparison of Differences in Cough Latency, Cough Frequency, FOIS, and Nutritional Oral Intake Before and After the 3-Week IFC-TESS

Dependent Variable	Independent Variable	B (95% CI)	β	p-value	VIF	Adjusted R^2
Cough latency	Age (years)	0.137 (−0.542 to 0.816)	0.062	0.687	1.143
	Sex	8.509 (−7.634 to 24.651)	0.156	0.294	1.059
	BMI (kg/m^2)	−0.570 (−3.493 to 2.353)	−0.073	0.697	1.700	−0.083
	MNA	0.409 (−2.281 to 3.098)	0.067	0.761	2.383
	BI score	0.064 (−0.315 to 0.442)	0.078	0.737	2.628
	MMSE score	−0.094 (−1.214 to 1.026)	−0.036	0.866	2.252
Cough frequency	Age (years)	0.022 (−0.040 to 0.084)	0.109	0.472	1.143
	Sex	0.730 (−0.739 to 2.198)	0.145	0.323	1.059
	BMI (kg/m^2)	−0.167 (−0.433 to 0.099)	−0.232	0.212	1.700	−0.046
	MNA	0.087 (−0.157 to 0.332)	0.156	0.477	2.383
	BI score	−0.003 (−0.037 to 0.032)	−0.034	0.883	2.628
	MMSE score	0.003 (−0.099 to 0.105)	0.013	0.952	2.252
FOIS	Age (years)	0.003 (−0.008 to 0.014)	0.088	0.557	1.143
	Sex	0.030 (−0.233 to 0.292)	0.033	0.821	1.059
	BMI (kg/m^2)	0.030 (−0.018 to 0.077)	0.228	0.217	1.700	−0.038
	MNA	−0.030 (−0.073 to 0.014)	−0.293	0.181	2.383
	BI score	0.000 (−0.007 to 0.006)	−0.026	0.909	2.628
	MMSE score	0.013 (0.006 to 0.031)	0.292	0.171	2.252
Nutritional oral intake	Age (years)	1.980 (−1.357 to 5.316)	0.182	0.239	1.143
	Sex	22.571 (−56.739 to 101.881)	0.084	0.570	1.059
	BMI (kg/m^2)	−0.680 (−15.041 to 13.681)	−0.018	0.925	1.700	−0.078
	MNA	−3.412 (−16.627 to 9.802)	−0.114	0.606	2.383
	BI score	0.011 (−1.849 to 1.872)	0.003	0.990	2.628
	MMSE score	0.774 (−4.729 to 6.276)	0.061	0.778	2.252

Note: Data are given for multiple regression model.

Abbreviations: B, unstandardized coefficient; β, standardized coefficient; BI, Barthel index; BMI, body mass index; IFC-TESS, interferential current transcutaneous electrical sensory stimulation; MMSE, mini-mental state examination; MNA, mini nutritional assessment; R², coefficient of determination; VIF, variance inflation factor; 95% CI, 95% confidence interval.