Effects of Age and Lingual-Palatal Pressure Levels on Submental Surface Electromyography Measures.

Submental surface electromyography (sEMG) may provide information about the lingual-palatal pressure (LPP) during swallowing. However, the extent to which changes in age and LPP levels are reflected in different sEMG measures is unclear. This study aimed to understand the effects of age and different levels of submaximal LPPs on submental sEMG peak, average, and integrated values in healthy adults. Ninety community-dwelling healthy participants were categorized into three age groups (young: 20-39 years, middle age: 40-59 years, older: 60 ≥ years). sEMG and LPP measurements were collected concurrently. After placing the sEMG electrodes, the maximal isometric LPP was established using the Iowa oral performance instrument (IOPI) on the anterior tongue. sEMG recordings were conducted for three submaximal LPP levels, including 40%, 60%, and 80% of the maximum LPP. Two-way repeated measure ANOVAs were conducted to find the effects of age and varying LPP levels on mean sEMG peak, average, and integrated measures. A significant age by LPP level interaction was identified for sEMG peak [F (4, 172) = 4.116, p < 0.007, ηp2 = 0.087], sEMG average [F (4, 170) = 5.049, p < 0.001, ηp2 = 0.106], and sEMG integrated values [F (4, 170) = 4.179, p < 0.003, ηp2 = 0.090]. Post hoc testing demonstrated that, in general, sEMG values significantly increased with rising LPP levels, primarily for younger and middle-aged adults. Furthermore, at 80% of maximum LPP, older adults generated less sEMG average and integrated values than middle age (only significant for sEMG integrated value) and younger adults. Likewise, max LPP was lower in older adults compared with young and middle-aged groups. Submental sEMG has the potential to be incorporated into a skill-based lingual exercise paradigm to improve tongue function during swallowing. Moreover, submental sEMG can characterize some age-related subclinical changes in swallowing.

Spontaneous Swallowing Frequency, Dysphagia, and Drooling in Children With Cerebral Palsy.

OBJECTIVE: To evaluate relationships between spontaneous swallowing frequency, dysphagia, and drooling in children with cerebral palsy. Spontaneous swallowing frequency was predicted to be inversely related to both dysphagia and drooling among children with cerebral palsy. A secondary objective compared patterns among spontaneous swallowing frequency, drooling, and age in healthy children vs children presenting with cerebral palsy. DESIGN: Cross sectional study. SETTING: Children with cerebral palsy were tested at a Cerebral Palsy Reference Center in a university hospital. Healthy children were tested in their home setting. PARTICIPANTS: Twenty children with cerebral palsy were recruited from the local registry for cerebral palsy children and purposive sampling among parents. A group of 30 healthy children was recruited by purposive sampling among family, friends, and the local community. Children below 1 year of age up to 5 years of age were included in the healthy group. This age range was targeted to maximize the potential for drooling in this group. MAIN OUTCOME MEASURES: Both groups provided data on spontaneous swallowing frequency (swallows per minute, or SPM), dysphagia, and drooling. Motor impairment was documented in the children with cerebral palsy. RESULTS: SPM was significantly lower in children with cerebral palsy. Among children with cerebral palsy, SPM correlated significantly with dysphagia severity and trended toward a significant correlation with drooling at rest. In this subgroup, SPM was not correlated with age or degree of motor impairment. Dysphagia was significantly correlated with drooling at rest and both dysphagia and drooling at rest were correlated with degree of motor impairment. The 2 groups did not differ in the degree of drooling at rest. Among healthy children, age but not SPM demonstrated a significant inverse correlation with drooling quotient at rest. CONCLUSIONS: Spontaneous swallowing frequency is related to dysphagia and drooling in children with cerebral palsy. The pattern of relationships among spontaneous swallowing frequency and drooling is different between children with cerebral palsy and younger healthy children.

Transcutaneous electrical stimulation as a resistance force in lingual exercise: A preliminary proof-of-concept study.

BACKGROUND: Limited knowledge exists regarding whether transcutaneous electrical stimulation (TES)-based exercise can improve the lingual pressure generation. OBJECTIVES: To compare the effect of submental TES with two different pulse durations (PD) coupled with isometric lingual exercises on lingual pressure measures. METHODS: Twenty-eight healthy volunteers were divided into two submental TES groups: short PD (300 µs) and long PD (700 µs). The Iowa Oral Performance Instrument (IOPI) was used for lingual pressure measurements and exercise. In total, participants attended six exercise sessions 3 days per week for 2 consecutive weeks. Maximum and swallowing lingual pressures were measured 1 h following each exercise session and 3 days after the final session to assess any detraining effect. Data were analysed using repeated measure ANOVA. RESULTS: Mean maximum lingual pressure change was significantly greater in TES with short PD versus the long PD condition following the first week of exercise. Following the 2-week exercise, a significant increase was found in mean maximum lingual pressure for short and long PD conditions compared with the baseline. However, no significant difference was found between PD conditions for maximum lingual pressure. Likewise, no significant differences in swallowing lingual pressure were found compared with the baseline or across the two TES conditions. CONCLUSION: Although short PD induced greater gain in maximum lingual pressure than the long PD after week 1, the enhanced effect faded after week 2, leading to a comparable increase in maximum lingual pressure for both groups. However, increased gain in maximum lingual pressure was not transferred to lingual pressure during swallowing.

Transcutaneous Electrical Stimulation on the Submental Area: The Relations of Biopsychological Factors with Maximum Amplitude Tolerance and Perceived Discomfort Level.

Transcutaneous electrical stimulation (TES) is a frequently used adjunctive modality in dysphagia rehabilitation. Stimulating deeper swallowing muscles requires higher TES amplitude. However, TES amplitude is limited by maximum amplitude tolerance (MAT). Previous studies have reported high interindividual variability regarding MAT and perceived discomfort. This variability might be one of the potential reasons of conflicting outcomes in TES-based swallowing studies. MAT and perceived discomfort are influenced by a variety of biopsychological factors. The influence of these factors related to swallow applications is poorly understood. This study explored the relation of biopsychological factors with MAT and perceived discomfort related to TES in the submental area. A convenience sample of thirty community-dwelling older adults between 60 and 70 years of age provided data for this study. Gender, submental adipose tissue thickness, perceptual pain sensitivity, and pain-coping strategies were evaluated for each subject. Subsequently, MAT and perceived discomfort level were determined using TES on the submental area. Relation of different biopsychological variables with MAT and discomfort level was examined using Pearson and Spearman correlation, and Mann-Whitney U test. Results indicated that neither gender nor adipose thickness was related to MAT and perceived discomfort. Among studied pain-coping strategies, catastrophizing was significantly related to MAT(r = - 0.552, p < .002). Distraction was significantly related to perceived discomfort level (r = - 0.561, p < 0.002). Given the negative impact of pain catastrophizing on MAT and the positive impact of distraction on perceiving discomfort, these coping strategies should be considered as amplitude-limiting and discomfort-moderating factors in TES-based dysphagia rehabilitation.

Exercise-based swallowing intervention (McNeill Dysphagia Therapy) with adjunctive NMES to treat dysphagia post-stroke: A double-blind placebo-controlled trial.

BACKGROUND: Dysphagia following stroke is prevalent; however, dysphagia treatment is often applied haphazardly and outcomes unclear. Neuromuscular electrical stimulation (NMES) has received increased attention as a treatment for post-stroke dysphagia; but application data remain conflicted. OBJECTIVE: This study investigated effectiveness and safety of an exercise-based swallowing therapy (McNeill Dysphagia Therapy: MDTP) +NMES for dysphagia rehabilitation following stroke. METHODS: Stroke patients (n = 53, x̅ age: 66 [13.2], 47.2% male) with dysphagia admitted to sub-acute rehabilitation hospital were randomised to MDTP + NMES [NMES], MDTP + sham NMES [MDTP] or usual care [UC] swallowing therapy groups. Patients were treated for 1 hour per day for 3 weeks and monitored to 3 months by a blinded evaluator. Outcomes included clinical swallowing ability, oral intake, weight, patient perception of swallow and occurrence of dysphagia-related complications. RESULTS: Post-treatment dysphagia severity and treatment response were significantly different between groups (P ≤ .0001). MDTP demonstrated greater positive change than either NMES or UC arms, including increase in oral intake (χ2  = 5, P ≤ .022) and improved functional outcome by 3 months post-stroke (RR = 1.72, 1.04-2.84). Exploratory Cox regression revealed the MDTP group conferred the greatest benefit in time to "return to pre-stroke diet" of 4.317 [95% CI: 1.08- 17.2, P< .03]. CONCLUSION: Greater benefit (eg reduction in dysphagia severity, improved oral intake and earlier return to pre-stroke diet) resulted from a programme of MDTP alone vs NMES or UC.

Associations Between Spontaneous Swallowing Frequency at Admission, Dysphagia, and Stroke-Related Outcomes in Acute Care.

OBJECTIVE: To expand the scope of prior spontaneous swallowing frequency analysis (SFA) studies, by evaluating the role of SFA in dysphagia-and stroke-related outcomes at acute stroke discharge. DESIGN: Period prevalence study. SETTING: Tertiary care university hospital. PARTICIPANTS: Patients with acute stroke (N=96). INTERVENTIONS: Subjects were screened for dysphagia using SFA. Mode of screening was 24 hours from identified stroke onset. All patients completed dysphagia- and stroke-related assessments. Patients were followed to discharge from acute care, and admission SFA was compared with status at discharge. RESULTS: Lower SFA rates at admission were significantly associated with presence of dysphagia. Lower SFA rates were also associated with persistent dysphagia and restricted diet at discharge. The SFA rates were lower for patients with identified aspiration on fluoroscopic swallowing study. Negative stroke-related outcomes from acute care were associated with lower SFA rates including disability at admission, disability and handicap at discharge, and institutionalization at discharge. Regression analysis identified SFA as an independent predictor of the negative composite outcome of death-disability-institutionalization. CONCLUSIONS: Swallowing frequency analysis not only has a high accuracy of dysphagia identification in acute stroke and relates to dysphagia severity, but it is also associated with multiple dysphagia- and stoke-related outcomes from acute care. Early poststroke dysphagia identification with SFA may lead to earlier and more effective interventions targeted at identified negative stroke outcomes.

Longitudinal Kinematic Evaluation of Pharyngeal Swallowing Impairment in Thyroidectomy Patients.

The aim of this study was to assess pharyngeal swallowing impairments in thyroidectomy patients and to delineate the contributory kinematic components. Forty consecutive patients (mean age = 47.33 years) and fourteen age- and sex-matched heathy adult volunteers (mean age = 42.64 years) participated in this study. A videofluoroscopic swallowing study (VFSS) was performed 1 day prior to surgery, and at 1 week and 3 months post-surgery. VFSS images were evaluated using the Modified Barium Swallowing Impairment Profile (MBSImp). Kinematic and temporal aspects of swallowing were characterized by measurement of maximum hyoid and laryngeal excursion, pharyngeal transit duration, laryngeal response duration (LRD), and laryngeal closure duration at each three time-points. At 1 week post-surgery, only pharyngeal impairment was significantly deteriorated than pre-surgery (p = 0.001). However, at 3 months, a significant improvement was observed to pre-surgery level (p = 0.01). Post-surgery, maximum hyoid excursion was significantly reduced in patients compared controls (p = 0.001). Although the maximal distance of the hyoid and the laryngeal excursion was shorter than before surgery, laryngeal excursion at all three time-points was similar to that of controls. At all three time-points, LRD was significantly longer in patients than in controls (p = 0.01). Following thyroidectomy, pharyngeal aspects of swallowing as measured by the MBSImp and kinematic aspects of swallowing were reduced with incomplete recovery at 3 months. These exploratory data may guide decision regarding management of pharyngeal swallowing impairment with patients undergoing total thyroidectomy.

The Effects of Electrical Stimulation Pulse Duration on Lingual Palatal Pressure Measures During Swallowing in Healthy Older Adults.

Limited research in swallowing physiology has suggested that the most common existing transcutaneous electrical stimulation (TES) protocol (VitalStim) may not penetrate to layers of tissue to affect deep swallowing muscles. TES amplitude is the primary parameter that determines the depth of electrical current penetration (DECP). Preliminary work suggests that replacing a long-pulse duration with a short-pulse duration can increase maximum amplitude tolerance (MAT) within subjects' comfort level. Increasing MAT may indicate a higher DECP. The current study evaluates this premise in reference to the effects of varying pulse duration on lingual-palatal pressure during swallowing. Thirty healthy older adults (60-70 years of age) participated in this study. Each subject swallowed three trials of 10 mL pudding under three TES conditions: no stimulation, short-pulse duration, and long-pulse duration. TES was delivered using two pairs of surface electrodes on the submental muscles. MAT and perceived discomfort levels were identified separately for short and long-pulse TES conditions. Lingual-palatal peak pressure, pressure integral, and pressure duration were measured under each condition. Two-way repeated measures ANOVAs were conducted to identify within subject effects of TES condition and tongue bulb location. Lingual-palatal pressure and pressure integral were significantly reduced in the short-pulse duration condition. MAT was significantly higher in the short-pulse duration versus the long-pulse duration condition. Furthermore, MAT was significantly correlated with lingual-palatal pressure. Changing pulse duration had no significant impact on tongue pressure duration. Results suggest that a short-pulse duration may penetrate deeper into muscles involved in swallowing. The specific impact is reflected in a reduced upward pressure of the tongue on the palate during swallowing. This 'restrictive' effect of TES on tongue pressure may have the potential to be used during a resistive exercise paradigm for tongue elevation during swallowing.

Dysphagia and Oral Morbidities in Chemoradiation-Treated Head and Neck Cancer Patients.

This study prospectively evaluated relationships between oral morbidities and swallowing ability in head/neck cancer patients following chemoradiation therapy (CRT) and at 3 months following CRT. Thirty patients with confirmed head/neck cancer undergoing chemoradiation were assessed with a battery of swallowing measures and measures of oral morbidities related to chemoradiation (xerostomia, mucositis, pain, taste/smell, oral moisture). All measures were completed at baseline (within the first week of CRT), at 6 weeks (end of treatment), and at 3 months following chemoradiation. Descriptive and univariate statistics were used to depict change over time in swallowing and each oral morbidity. Correlation analyses evaluated relationships between swallowing function and oral morbidities at each time point. Most measures demonstrated significant negative change at 6 weeks with incomplete recovery at 3 months. At 6 weeks, mucositis ratings, xerostomia, and retronasal smell intensity demonstrated significant inverse relationships with swallowing function. In addition, oral moisture levels demonstrated significant positive relationships with swallowing function. At 3 months, mucositis ratings maintained a significant, inverse relationship with swallow function. Taste and both orthonasal and retronasal smell intensity ratings demonstrated inverse relationships with measures of swallow function. Swallow functions and oral morbidities deteriorate significantly following CRT with incomplete recovery at 3 months post treatment. Furthermore, different patterns of relationships between swallow function measures and oral morbidities were obtained at the 6-week versus the 3-month assessment point suggesting that different mechanisms may contribute to the development versus the maintenance of dysphagia over the trajectory of treatment in these patients.

Transcutaneous electrical stimulation on the anterior neck region: The impact of pulse duration and frequency on maximum amplitude tolerance and perceived discomfort.

Maximum amplitude tolerance (MAT) has been known as a primary factor determining the depth of electrical current penetration. However, the effect of varying transcutaneous electrical stimulation (TES) parameters on MAT and discomfort level is poorly understood. Furthermore, limited information exists regarding the biopsychological factors that may impact MAT and discomfort. The primary aims of this study were to compare the effects TES protocol with varying levels of pulse duration (300 µs vs 700 µs) and frequency (30 Hz vs 80 Hz) on the MAT and discomfort in healthy older adults. The exploratory aim of this study was to examine relationships between submental adipose tissue thickness, pain sensitivity and gender with MAT and discomfort. Twenty-four healthy older adults participated in this study. Transcutaneous electrical stimulation was delivered to the submental region. Maximum amplitude tolerance and discomfort were measured for each condition. Furthermore, submental adipose tissue thickness and pain sensitivity were measured for each subject. Maximum amplitude tolerance was significantly increased for the TES protocols with short-pulse duration [F (3, 69) = 38.695, P < .0001]. Discomfort was similar across different TES protocols. Submental adipose tissue thickness (r = .30, P < .003) and pain sensitivity (r = -.43, P < .0001) were related to MAT. Pain sensitivity rating was also related to discomfort (r = .45, P < .0001). In conclusion, using TES protocols with short-pulse duration may increase the MAT. Higher amplitude stimulation may increase the impact on deep swallowing muscles. In addition, submental adipose tissue thickness and pain sensitivity are potential biopsychological factors that may affect MAT and discomfort.

Effect of transcutaneous electrical stimulation amplitude on timing of swallow pressure peaks between healthy young and older adults.

OBJECTIVES: This study compared the effect of transcutaneous electrical stimulation (TES) amplitude on timing of lingual-palatal and pharyngeal peak pressures during swallowing in healthy younger and older adults. BACKGROUND: Transcutaneous electrical stimulation amplitude is one parameter that may have different impacts on the neuromotor system and swallowing physiology. One aspect of swallowing physiology influenced by age is the timing of swallowing events. However, the effect of varying TES amplitudes on timing of swallowing physiology is poorly understood, especially in older adults. MATERIALS AND METHODS: Thirty-four adults (20 younger and 14 older) swallowed 10 ml of nectar-thick liquid under three TES conditions: no stimulation, low-amplitude stimulation and high-amplitude stimulation. TES was delivered by surface electrodes on the anterior neck. Timing of pressure peaks for lingual-palatal contacts and pharyngeal pressures were measured under each condition. RESULTS: A significant age × stimulation amplitude interaction was identified for the base of tongue (BOT) [F(2,62) = 5.087, p < 0.009] and the hypopharynx (HYPO) [F(2,62) = 3.277, p < 0.044]. At the BOT, low-amplitude TES resulted in slower swallows in the younger adults compared with no TES. In older adults, low-amplitude TES resulted in faster swallows compared with high-amplitude TES. At the HYPO, no significant differences were identified in pressure timing across the three TES amplitudes in both age groups. In each case, low-amplitude TES resulted in faster swallows in older adults compared with younger adults. CONCLUSIONS: Transcutaneous electrical stimulation influences pharyngeal pressure timing differently in young and old people, which questions the appropriateness of using a 'one-size-fits-all' TES amplitude for rehabilitating people with dysphagia.

Clinical Variables Associated with Hydration Status in Acute Ischemic Stroke Patients with Dysphagia.

Acute stroke patients with dysphagia are at increased risk for poor hydration. Dysphagia management practices may directly impact hydration status. This study examined clinical factors that might impact hydration status in acute ischemic stroke patients with dysphagia. A retrospective chart review was completed on 67 ischemic stroke patients who participated in a prior study of nutrition and hydration status during acute care. Prior results indicated that patients with dysphagia demonstrated elevated BUN/Cr compared to non-dysphagia cases during acute care and that BUN/Cr increased selectively in dysphagic patients. This chart review evaluated clinical variables potentially impacting hydration status: diuretics, parenteral fluids, tube feeding, oral diet, and nonoral (NPO) status. Exposure to any variable and number of days of exposure to each variable were examined. Dysphagia cases demonstrated significantly more NPO days, tube fed days, and parenteral fluid days, but not oral fed days, or days on diuretics. BUN/Cr values at discharge were not associated with NPO days, parenteral fluid days, oral fed days, or days on diuretics. Patients on modified solid diets had significantly higher mean BUN/Cr values at discharge (27.12 vs. 17.23) as did tube fed patients (28.94 vs. 18.66). No difference was noted between these subgroups at baseline (regular diet vs. modified solids diets). Any modification of solid diets (31.11 vs. 17.23) or thickened liquids (28.50 vs. 17.81) resulted in significantly elevated BUN/Cr values at discharge. Liquid or diet modifications prescribed for acute stroke patients with dysphagia may impair hydration status in these patients.

Immediate effects of transcutaneous electrical stimulation on physiological swallowing effort in older versus young adults.

OBJECTIVE: This study compared the immediate impact of different transcutaneous electrical stimulation (TES) amplitudes on physiological swallowing effort in healthy older adults versus young adults. BACKGROUND: Swallowing physiology changes with age. Reduced physiological swallowing effort in older adults including lower lingua-palatal and pharyngeal pressures may increase risk for swallowing dysfunction (i.e. dysphagia). Transcutaneous electrical stimulation (TES) has been advocated as an adjunctive modality to enhance outcomes in exercise-based therapy for individuals with dysphagia. However, significant variation in how TES is applied during therapy remains and the physiological swallowing response to TES is poorly studied, especially in older adults. MATERIALS AND METHODS: Physiological change in swallowing associated with no stimulation, sensory stimulation and motor stimulation was compared in 20 young adults versus 14 older adults. Lingua-palatal and pharyngeal manometric pressures assessed physiological swallowing effort. RESULTS: Multivariate analyses identified interactions between age and stimulation amplitude on lingual and pharyngeal functions. Motor stimulation reduced anterior tongue pressure in both age groups but selectively reduced posterior lingua-palatal pressures in young adults only. Sensory stimulation increased base of tongue (BOT) pressures in older adults but decreased BOT pressures in young adults. Motor stimulation increased hypopharyngeal pressures in both groups. CONCLUSION: Age and TES level interact in determining immediate physiological responses on swallow performance. A one-size-fit-all approach to TES in dysphagia rehabilitation may be misdirected.

Effects of Age and Bolus Volume on Velocity of Hyolaryngeal Excursion in Healthy Adults.

Reduced movement velocity has been identified as a risk marker for movement impairment in older adults. Hyolaryngeal excursion is a key movement feature of normal swallowing function which is known to change with age and other extrinsic variables such as bolus volume. However, velocity of hyolaryngeal excursion has received limited attention in the literature on normal or abnormal swallowing. This study evaluated the effects of age and bolus volume on the velocity of hyoid and laryngeal excursion during swallowing in healthy adults. Forty-four healthy volunteers were grouped into three age bands (young: 20-35 years, middle age: 36-55 years, older: 56 ≥ years). All subjects swallowed 5 and 20 mL of thin liquid during fluoroscopic recording. Fluoroscopic images were extracted for each swallow representing the onset and maximum excursion positions of the hyoid and larynx. Superior and anterior excursion distance (excursion magnitude) and the time difference between rest and maximum excursion (excursion duration) were calculated. Velocity was calculated as a ratio of distance over time. Superior hyoid excursion magnitude was significantly increased for the 20 mL volume. Anterior laryngeal excursion magnitude was also significantly increased for the 20 mL volume. No kinematic duration measure demonstrated significant change across age or bolus conditions. Superior hyoid excursion velocity was significantly faster for the 20 mL volume. Superior and anterior laryngeal excursion velocity were significantly faster for the 20 mL volume only in the older group. Results of this study indicate that magnitude and velocity of hyoid and laryngeal excursion vary with age and volume. Comprising both excursion magnitude and duration, kinematic velocity may be a more complete metric to evaluate age-related swallowing performance.

'Food Sticking in My Throat': Videofluoroscopic Evaluation of a Common Symptom.

Prevalence of the symptom of food 'sticking' during swallowing has been reported to range from 5 to 50%, depending on the assessment setting. However, limited objective evidence has emerged to clarify factors that contribute to this symptom. Three hundred and fifteen patient records from an outpatient dysphagia clinic were reviewed to identify patients with symptoms of 'food sticking in the throat.' Corresponding videofluoroscopic swallowing studies for patients with this complaint were reviewed for the following variables: accuracy of symptom localization, identification and characteristics (anatomic, physiologic) of an explanatory cause for the symptom, and the specific swallowed material that identified the explanatory cause. One hundred and forty one patients (45%) were identified with a complaint of food 'sticking' in their throat during swallowing. Prevalence of explanatory findings on fluoroscopy was 76% (107/141). Eighty five percent (91/107) of explanatory causes were physiologic in nature, while 15% (16/107) were anatomic. The majority of explanatory causes were identified in the esophagus (71%). Symptom localization was more accurate when the explanatory cause was anatomic versus physiologic (75 vs. 18%). A non-masticated marshmallow presented with the highest diagnostic yield in identification of explanatory causes (71%). Patients complaining of 'food sticking in the throat' are likely to present with esophageal irregularities. Thus, imaging studies of swallowing function should include the esophagus. A range of materials, including a non-masticated marshmallow, is helpful in determining the location and characteristics of swallowing deficits contributing to this symptom.

Development and validation of a cancer-specific swallowing assessment tool: MASA-C.

OBJECTIVE: We present data from a sample of patients receiving radiotherapy for head/neck cancer to define and measure the validity of a new clinical assessment measure for swallowing. METHODS: Fifty-eight patients undergoing radiotherapy (±chemotherapy) for head/neck cancer (HNC) supported the development of a physiology-based assessment tool of swallowing (Mann Assessment of Swallowing Ability--Cancer: MASA-C) administered at two time points (baseline and following radiotherapy treatment). The new exam was evaluated for internal consistency of items using Cronbach's alpha. Reliability of measurement was evaluated with intraclass correlation (ICC) and the Kappa statistic between two independent raters. Concurrent validity was established through comparison with the original MASA examination and against the referent standard videofluoroscopic swallowing examination (VFE). Sensitivity, specificity, and likelihood ratios along with 95 % confidence intervals (CIs) were derived for comparison of the two evaluation forms (MASA vs. MASA-C). Accuracy of diagnostic precision was displayed using receiver operator characteristic curves. RESULTS: The new MASA-C tool demonstrated superior validity to the original MASA examination applied to a HNC population. In comparison to the VFE referent exam, the MASA-C revealed strong sensitivity and specificity (Se 83, Sp 96), predictive values (positive predictive value (PPV) 0.95, negative predictive value (NPV) 0.86), and likelihood ratios (21.6). In addition, it demonstrated good reliability (ICC = 0.96) between speech-language pathology raters. CONCLUSIONS: The MASA-C is a reliable and valid scale that is sensitive to differences in swallowing performance in HNC patients with and without dysphagia. Future longitudinal evaluation of this tool in larger samples is suggested. The development and refinement of this swallowing assessment tool for use in multidisciplinary HNC teams will facilitate earlier identification of patients with swallowing difficulties and enable more efficient allocation of resources to the management of dysphagia in this population. The MASA-C may also prove useful in future clinical HNC rehabilitation trials with this population.

Spontaneous swallow frequency compared with clinical screening in the identification of dysphagia in acute stroke.

BACKGROUND: The aim of this study was to compare spontaneous swallow frequency analysis (SFA) with clinical screening protocols for identification of dysphagia in acute stroke. METHODS: In all, 62 patients with acute stroke were evaluated for spontaneous swallow frequency rates using a validated acoustic analysis technique. Independent of SFA, these same patients received a routine nurse-administered clinical dysphagia screening as part of standard stroke care. Both screening tools were compared against a validated clinical assessment of dysphagia for acute stroke. In addition, psychometric properties of SFA were compared against published, validated clinical screening protocols. RESULTS: Spontaneous SFA differentiates patients with versus without dysphagia after acute stroke. Using a previously identified cut point based on swallows per minute, spontaneous SFA demonstrated superior ability to identify dysphagia cases compared with a nurse-administered clinical screening tool. In addition, spontaneous SFA demonstrated equal or superior psychometric properties to 4 validated, published clinical dysphagia screening tools. CONCLUSIONS: Spontaneous SFA has high potential to identify dysphagia in acute stroke with psychometric properties equal or superior to clinical screening protocols.

Spontaneous swallowing frequency has potential to identify dysphagia in acute stroke.

BACKGROUND AND PURPOSE: Spontaneous swallowing frequency has been described as an index of dysphagia in various health conditions. This study evaluated the potential of spontaneous swallow frequency analysis as a screening protocol for dysphagia in acute stroke. METHODS: In a cohort of 63 acute stroke cases, swallow frequency rates (swallows per minute [SPM]) were compared with stroke and swallow severity indices, age, time from stroke to assessment, and consciousness level. Mean differences in SPM were compared between patients with versus without clinically significant dysphagia. Receiver operating characteristic curve analysis was used to identify the optimal threshold in SPM, which was compared with a validated clinical dysphagia examination for identification of dysphagia cases. Time series analysis was used to identify the minimally adequate time period to complete spontaneous swallow frequency analysis. RESULTS: SPM correlated significantly with stroke and swallow severity indices but not with age, time from stroke onset, or consciousness level. Patients with dysphagia demonstrated significantly lower SPM rates. SPM differed by dysphagia severity. Receiver operating characteristic curve analysis yielded a threshold of SPM≤0.40 that identified dysphagia (per the criterion referent) with 0.96 sensitivity, 0.68 specificity, and 0.96 negative predictive value. Time series analysis indicated that a 5- to 10-minute sampling window was sufficient to calculate spontaneous swallow frequency to identify dysphagia cases in acute stroke. CONCLUSIONS: Spontaneous swallowing frequency presents high potential to screen for dysphagia in acute stroke without the need for trained, available personnel.

Validation and demonstration of an isolated acoustic recording technique to estimate spontaneous swallow frequency.

Spontaneous swallowing is considered a reflexive, pharyngeal clearance mechanism. Reductions in spontaneous swallow frequency may be a sensitive index for dysphagia and related morbidities. This study evaluated an acoustic recording technique as a measure to estimate spontaneous swallow frequency. Initially, a multichannel physiologic (surface electromyography, swallow apnea, cervical auscultation) recording technique was validated and subsequently compared to an isolated acoustic (microphone) recording technique on a sample of younger (25 ± 2.8 years) and older (68 ± 5.3 years) healthy adult participants. Sensitivity (94 %), specificity (99 %), and classification accuracy (98 %) were high for swallow identification from the multichannel physiologic recording technique. Interjudge reliability was high (k = 0.94, 95 % CI = 0.92-0.96). No significant differences in spontaneous swallow frequency were observed between the multichannel physiologic recordings and the acoustic recordings (0.85 vs. 0.81 swallows per minute). Furthermore, these two techniques were highly correlated (r = 0.95). Interjudge reliability for swallow identification via acoustic recordings was high (k = 0.96, 95 % CI = 0.94-0.99). Preliminary evaluation of the temporal stability of spontaneous swallow frequency measured from acoustic recordings indicated that time samples as short as 5 min produce viable results. Age differences were identified in spontaneous swallow frequency rates, with older participants swallowing less frequently than younger participants (0.47 vs. 1.02 swallows per minute). Collectively, these results indicate that an isolated acoustic recording technique is a valid approach to estimate spontaneous swallow frequency.

Dysphagia, nutrition, and hydration in ischemic stroke patients at admission and discharge from acute care.

Dysphagia may predispose stroke patients toward undernutrition and hydration. These comorbidities increase patient risks for reduced functional outcome and short-term mortality. Despite this impact, available information on relationships among dysphagia, nutrition, and hydration status in acute stroke is limited and conflicted. This study evaluated nutrition and hydration status in ischemic stroke patients with versus without clinically significant dysphagia at admission and at discharge from acute care. Sixty-seven patients admitted to the stroke unit in a tertiary-care hospital provided data for this study. On the day of hospital admission and upon discharge or at 7 days post admission, serum biochemical measures were obtained for nutrition (prealbumin) and hydration status (BUN/Cr). Clinical evaluation for dysphagia, nutrition status, and stroke severity were completed an average of 1.4 days following hospital admission. Dysphagia was identified in 37 % of the cohort. At admission 32 % of patients demonstrated malnutrition based on prealbumin levels and 53 % demonstrated evidence of dehydration based on BUN/Cr levels. No differences in nutrition status were attributed to dysphagia. Patients with dysphagia demonstrated significantly higher BUN/Cr levels (greater dehydration) than patients without dysphagia at admission and at discharge. Dehydration at both admission and discharge was associated with dysphagia, clinical nutrition status, and stroke severity. Results of this study support prior results indicating that dysphagia is not associated with poor nutrition status during the first week post stroke. Dehydration status is associated with dysphagia during this period. The results have implications for future confirmatory research and for clinical management of dysphagia in the acute stroke period.