Submental Muscle Activity and Its Role in Diagnosing Sarcopenic Dysphagia

Figures & data

Figure 1 Placement of the electrodes for surface electromyography measurement.

Table 1 Characteristics of Study Participants

	Non-Dysphagic Group (n = 30)	Dysphagic Group (n = 30)	p-value
Age (years)	88 [79.75–91.00]	89 [85.00–90.00]	0.58
CCI	1 [0–2]	1 [1–2]	0.16
CRP (mg/dl)	0.40 [0.093–0.94]	0.60 [0.22–1.73]	0.25
SMI (kg/m^2)	5.04 [4.69–6.36]	4.39 [3.16–5.02]	0.002
Fat percentage (%)	25.7 [21.20–35.5]	19.1 [16.95–24.7]	0.003
Grip strength (kg)	17.4 [12.70–23.00]	12.0 [8.40–13.50]	<0.001
Sarcopenia	24 (80.0)	30 (100.0)	0.02
Malnutrition	16 (53.3)	29 (96.7)	<0.001
FOIS	6 [6–7]	5 [2.25–5]	<0.001
BI	66.5 [41.25–85.00]	30 [5.00–40.00]	<0.001
MMSE	23 [21.00–27.75]	21 [21.00–24.00]	0.02
BMI (kg/m^2)	19.6 [16.98–21.30]	16.7 [14.38–17.75]	<0.001
Primary Disease			0.05
Orthopedics	13 (43.3)	9 (30.0)
Digestive disorder	3 (10.0)	11 (36.7)
Heart failure	14 (46.7)	10 (33.3)

Note: Data are expressed as n (%) or median [interquartile range].

Abbreviations: BI, Barthel Index; BMI, body mass index; CCI, Charlson Comorbidity Index; CRP, C-reactive protein; FOIS, functional oral intake scale; MMSE, Mini-Mental State Examination; MNA-SF, Mini Nutritional Assessment Short-Form; SMI, Skeletal Muscle Mass Index.

Table 2 Comparison of sEMG Parameters and Lingual Pressure in the Non-Dysphagic and Sarcopenic Dysphagic Groups

	Non-Dysphagic Group	Dysphagic Group	p-value
Duration A (s)	0.27 [0.20–0.33]	0.31 [0.22–0.49]	0.15
Duration B (s)	1.00 [0.87–1.46]	2.54 [1.86–4.99]	<0.001
Total duration (s)	1.35 [1.14–1.75]	3.023 [2.27–5.85]	<0.001
Mean amplitude (% JOC)	95.29 [69.12–143.77]	169.33 [86.36–230.85]	0.014
Max. amplitude (% JOC)	224.64 [143.40–342.90]	451.81 [247.62–729.93]	<0.001
Lingual pressure (kPa)	26.75 [21.43–31.78]	18.10 [14.20–23.075]	<0.001

Note: Data are expressed as median [interquartile range].

Abbreviations: Max., maximum; s, second; sEMG, surface electromyograph; JOC, jaw opening contraction.

Table 3 Diagnostic Accuracy of sEMG Parameters and Cut-Off Values for Sarcopenic Dysphagia

	AUC (95% CI)	Cut-Off	Sensitivity	Specificity	DOR
Duration A (s)	0.61 (0.45–0.75)	0.44	0.33	0.9	4.5
Duration B (s)	0.94 (0.87–0.98)	1.61	0.9	0.83	45
Total duration (s)	0.95 (0.89–0.99)	1.96	0.93	0.87	91
Mean amplitude (% JOC)	0.61 (0.47–0.75)	143.32	0.57	0.73	3.60
Max. amplitude (% JOC)	0.76 (0.63–0.87)	387.09	0.57	0.83	6.54
Lingual pressure (kPa)	0.81 (0.69–0.91)	24	0.7	0.8	9.33

Abbreviations: AUC, area under the curve; CI, confidence interval; DOR, diagnostic odds ratio; JOC, jaw opening contraction; Max., maximum; s, second; sEMG, surface electromyograph.

Figure 2 Submental surface electromyography (sEMG) patterns in patients without and with dysphagia. (A) sEMG pattern in a patient without dysphagia. (B) sEMG pattern in a patient with sarcopenic dysphagia. Left-most blue vertical line, swallow onset; middle blue vertical line, maximum amplitude point; right-most blue vertical line, end of the swallowing activity.

Table 4 Association Between Duration, Amplitude, and Sarcopenia-Related Factors

Dependent Variables	Independent Variables	Coefficient (SE)	p-value
Total duration	Age (years)	0.02 (0.05)	0.64
	BI	−0.03 (0.01)	<0.001
	Malnutrition	1.80 (0.71)	0.01
	Grip strength (kg)	−0.19 (0.05)	0.001
	SMI (kg/m^2)	−0.34 (0.24)	0.16
	Fat percentage (%)	−0.08 (0.04)	0.07
	Lingual pressure (kPa)	−0.08 (0.04)	0.04
Maximum amplitude	Age (years)	0.54 (7.20)	0.94
	BI	−2.95 (1.60)	0.07
	Malnutrition	144.52 (108.82)	0.19
	Grip strength (kg)	−17.22 (8.69)	0.05
	SMI (kg/m^2)	−78.74 (33.91)	0.02
	Fat percentage (%)	−6.43 (6.26)	0.31
	Lingual pressure (kPa)	−8.59 (5.50)	0.12

Abbreviations: BI, Barthel Index; SE, standard error; SMI, Skeletal Muscle Mass Index.

Figure 3 Receiver operating characteristic curve for the diagnosis of sarcopenic dysphagia.