Prevalence of and Risk Factors for Dysphagia in the Community Dwelling Elderly: A Systematic Review.

OBJECTIVES: This review clarifies current information regarding the prevalence of and risk factors associated with dysphagia (swallowing disorders) in the community dwelling elderly (CDE). A better understanding of prevalence and characteristics of dysphagia in the CDE will help to determine the scope of this problem. Understanding the scope of dysphagia is a critical first step towards early identification, management, and prevention of dysphagia related morbidities in the CDE. METHODS: Studies identified from multiple electronic databases (MEDLINE (Pubmed), PsychInfo, Google Scholar, EBSCO, PROQUEST, Web of Science and WorldCat dissertations and theses) evaluating prevalence and risk factors for dysphagia in the CDE were reviewed. Data from all eligible studies were abstracted by the first author and independently reviewed by two raters, using the Newcastle-Ottawa scale (NOS). RESULTS: 15 studies (n = 9947 participants) were eligible for inclusion. Studies included were all observational: 14 cross-sectional and 1 prospective cohort. Significant heterogeneity was observed in methodology among studies of dysphagia in the CDE. The average NOS study quality rating was 4.54 points (SD: 0.9), with a mode of 4 points (range 3-6). Only 6 of the 15 studies were identified as high quality research studies, with a mean of 5.33 points (SD: 0.47). Among reviewed studies, the prevalence of swallowing difficulty in the CDE ranged from 5% to 72%. However, the average prevalence of dysphagia estimated from the 6 high quality studies was 15%. Reported risk factors associated with dysphagia include advancing age; history of clinical disease; and physical frailty, including reduced ability to carry out activities of daily living. CONCLUSION: Research on dysphagia in CDE is modest and consists mostly of observational studies with diverse methodology. However, prevalence rate of 15% from the high quality research suggests a significant public health impact of this impairment. Identification of specific risk factors that cause dysphagia in the CDE is premature, given the rigor of published studies. Future research efforts should focus on developing a valid definition and assessment of dysphagia in this population before clarifying causative risk factors.

Hyoid and laryngeal excursion kinematics - magnitude, duration and velocity - changes following successful exercise-based dysphagia rehabilitation: MDTP.

Variability in magnitude of deglutitional hyolaryngeal excursion in patients with dysphagia suggests that it does not adequately represent the kinematics of swallowing difficulties or recovery following rehabilitation. On the other hand, reduced hyolaryngeal excursion velocity has been reported in patients with dysphagia. While increased movement velocity often accompanies clinical and functional recovery in many diseases, velocity changes in swallowing-related movement following dysphagia therapy have not been well studied. This study evaluated changes in hyoid and laryngeal excursion (magnitude, duration and velocity) before and following successful dysphagia therapy to provide a more comprehensive representation of improvement to swallowing kinematics in patients who have experienced successful rehabilitation. A secondary analysis of case series data was completed. Eight patients with severe, chronic dysphagia completed a standard course of an exercise-based dysphagia treatment programme (McNeill dysphagia therapy program, MDTP). Pre- and post-treatment, kinematic aspects of swallowing were evaluated for thin liquid, thick liquid and pudding swallows. Maximum hyoid and laryngeal excursion magnitude and excursion duration were measured. Excursion velocities were calculated from excursion magnitude and duration measures. Successful treatment for dysphagia facilitated increased hyolaryngeal excursion magnitude, duration and velocity. These changes were most prominent for the hyoid and most often observed with thin liquids. By examining hyoid and laryngeal excursion velocity in patients who have experienced successful dysphagia rehabilitation, this study demonstrated the value of evaluating spatial and temporal aspects of swallowing kinematics in a single measure for a more comprehensive representation of positive changes underlying functional recovery.

Laryngeal recovery following type I thyroplasty.

OBJECTIVE: To describe the pattern of laryngeal recovery and its relationship to voice improvement following thyroplasty. DESIGN: We used a 5-point scale to rate 5 laryngeal characteristics preoperatively and 1 day, 1 week, 1 month, and 3 months following thyroplasty. SETTING: A university-affiliated health center. PATIENTS: Forty-four patients who underwent thyroplasty to correct incomplete glottal closure. RESULTS: Improved glottal closure and reduced supraglottic activity followed thyroplasty. Although evidence of postoperative irritation (erythema, edema, or hematoma) was present in many patients, it resolved within the first 1 to 4 weeks postoperatively in 22 (73%) of the 30 subjects available for follow-up at 3 months following thyroplasty. CONCLUSIONS: Thyroplasty is an effective procedure in correcting incomplete glottal closure and works to reduce excessive supraglottic activity in some patients. Recovery from postoperative vocal-fold irritation occurs rapidly, typically between the first week to first month, depending on the type and severity of irritation. These findings may help explain variations in postoperative voice improvement.

Surface electromyographic characteristics of swallowing in dysphagia secondary to brainstem stroke.

Surface electromyography (SEMG) provides an noninvasive avenue for evaluating swallowing physiology. This report describes SEMG characteristics associated with swallow attempts in 6 dysphagic patients who had suffered brainstem stroke compared with 6 age and gender-matched controls. Results indicated that patients with dysphagia secondary to brainstem stroke differed in both amplitude and timing aspects of swallowing attempts from asymptomatic controls. Specifically, the results indicated that during swallow attempts, dysphagic patients produced more muscle activity over a shorter duration and with less coordination than controls. Potential physiological mechanisms of these results are discussed.

Dynamic magnetic resonance imaging in the study of vocal tract configuration.

Studies of vocal tract configuration using magnetic resonance imaging (MRI) techniques have relied on static images. These images fail to identify transient movements and are subject to distortion from motion artifact limiting research application to stable motor events. This paper describes a dynamic MRI technique that permits study of transient movements within the vocal tract during speech and nonspeech tasks. Following description of the technique, results of two preliminary studies are presented. The initial study evaluated issues of measurement error and reliability. Results indicated that distance and area measurements obtained from this technique are accurate in reference to a calibration referent and reliable both within and among judges. The second study compared two aspects of vocal tract configuration in patients with adductor spasmodic dysphonia before and following treatment with Botox injection. Changes in vocal tract configuration are discussed in reference to prior observations of patients with spasmodic dysphonia. These preliminary investigations suggest that dynamic MRI has promise as a useful technique in the study of vocal tract configuration.

Using botulinum toxin A to improve speech and swallowing function following total laryngectomy.

OBJECTIVE: To evaluate a technique to reduce dysfunctional spasm in the pharyngoesophageal segment (PES) in patients after laryngectomy. DESIGN: Pharyngoesophageal segment function related to voice and/or swallowing in patients who had undergone a laryngectomy was evaluated before and after the injection of botulinum toxin A. SETTING: Academic referral medical center. PATIENTS: Eight outpatients with voice and/or swallowing complaints after undergoing a total laryngectomy. INTERVENTIONS: Videofluoroscopic contrast examination was completed to identify stricture vs spasm in the PES in patients with voice and/or swallowing complaints after undergoing a laryngectomy. Lidocaine hydrochloride injection under fluoroscopic guidance was completed to facilitate immediate relaxation of spasm. After positive results with lidocaine, botulinum toxin was injected into the same area to facilitate longer-lasting benefit. MAIN OUTCOME MEASURE: Patient report of benefit and videofluoroscopic evaluation of PES function. RESULTS: Six of 8 patients demonstrated improved function within the PES after lidocaine injection. Five of these 6 received transcutaneous injection of botulinum toxin. Four of the 5 patients demonstrated improved swallowing and/or voice function, and 3 of these 4 received subsequent injections of botulinum. No serious complications were encountered. CONCLUSIONS: Transcutaneous injection of botulinum toxin in the PES under videofluoroscopic guidance provides improvement in voice and/or swallowing function without significant complications. Additional clinical study will be required to evaluate dose and technique influences on degree and duration of benefit and complications.

Laryngeal aerodynamic aspects of women with adductor spasmodic dysphonia.

OBJECTIVE: To determine if laryngeal aerodynamic parameters distinguish the voice of patients diagnosed as having adductor spasmodic dysphonia (SD) from individuals with normal voice production. DESIGN: A group comparison between 10 women diagnosed as having adductor SD and 10 women with no evidence of vocal abnormalities or vocal dysfunction. SETTING: University and university-affiliated health center. PATIENTS: Ten women (age range, 38 through 82 years) diagnosed as having adductor SD and 10 age-matched women (+/- 2 years) with no evidence of pathologic vocal features or vocal dysfunction. RESULTS: Multivariate statistical analysis revealed significantly higher values for amplitude-based glottal airflow measures of maximum flow declination rate, peak glottal airflow, and minimum glottal airflow. CONCLUSIONS: Spasmodic dysphonia affects the ability of the laryngeal mechanism to function effectively. To date, few empirical studies have examined glottal airflow characteristics associated with adductor SD. Results from our study demonstrate that certain amplitude-based glottal airflow parameters distinguish adductor SD from normal voice. Therefore, aerodynamic measures may offer additional objectivity for the study.

Laryngeal complications after type 1 thyroplasty.

Type I thyroplasty has become a primary surgical choice for voice restoration in patients with glottal incompetence. This study examines factors associated with laryngeal complications after type I thyroplasty. Ten laryngoscopic variables were analyzed from preoperative, intraoperative, and postoperative videolaryngoscopies of 51 patients undergoing 58 medialization procedures. Ten patient and operative variables were examined by medical record review. Major complications were defined as wound hemorrhage, airway obstruction, or prosthesis extrusion. Minor complications were defined as vocal fold hematoma without airway obstruction or prosthesis movement. The major complication rate was 8.6%, and the minor complication rate was 29%. No delayed hemorrhage or airway obstruction occurred. Prosthesis extrusion occurred in five (8.6%) patients 1 week to 5 months after surgery. Extrusion was associated with suboptimal prosthesis placement in 80% of cases. Two patients retained excellent glottal closure despite extrusion. Vocal fold hematoma was identified in 14 (24%) cases and resolved within 1 week. Prosthesis movement occurred in three (5%) patients 1 week to 6 months after surgery and resulted in poor glottal closure. All patients with prosthesis extrusion or movement were female. Type I thyroplasty remains a safe outpatient procedure with few major complications. Prosthesis extrusion was associated with suboptimal prosthesis placement and may or may not result in poor glottal closure. Minor vocal fold hematomas were relatively frequent, resolved rapidly, and were not associated with airway obstruction. Female patients may be more prone to complications because of their small laryngeal size.

A direct intervention program for chronic neurogenic dysphagia secondary to brainstem stroke.

Little objective documentation is available regarding the efficacy of therapies for oropharyngeal dysphagia. Information specifying efficacy of treatment for chronic dysphagic conditions is almost nonexistent. This report describes a direct therapy program for chronic neurogenic dysphagia resulting from brainstem stroke, and provides information on immediate and long-term clinical outcome. Changes in swallowing physiology reflect goals of therapy. Long-term follow-up shows that functional benefits are long lasting without related health complications.

Objective distance measurements from videofluorographic swallow studies using computer interactive analysis: technical note.

Application of new technologies to study swallowing and its disorders will facilitate better understanding of both normal and disordered swallowing. Recent application of computer-assisted analysis of video-fluorographic swallow tapes has enhanced objective measurement of distance as well as timing characteristics of swallowing. Application of these systems requires consideration of system capability, calibration for distance measures, nature of measurements, and potential clinical/research benefits. This report describes a commercially available computer-interactive system for analyzing video images, discusses calibration procedures, and demonstrates practical applications using defined measures.

Production of linguistic prosody by normal and speech-disordered children.

Features associated with the production of linguistic prosody were investigated in seven speech-disordered children and seven children with age-appropriate speech abilities. All subjects were required to imitate 40 stimuli containing either a rising or falling terminal contour. Half of the stimuli were meaningful sentences whereas the other half were nonmeaningful repetitions of a single syllable. Both types of stimuli were produced with the same suprasegmental features. Acoustic analyses were used to measure a variety of prosodic features associated with the intonation (Fo) and timing characteristics of the imitated stimuli. The primary differences between the two groups of children focused on timing characteristics of the imitated responses. Differences in Fo characteristics also were identified, but in some instances interacted with timing deviations. Results are discussed in reference to potential physiologic and/or linguistic processes that might contribute to dysprosody in speech-disordered children.

Human pinch-force discrimination.

Pinch-sustaining tasks such as holding a pencil, fork, or key require the exertion of different levels of force. There is little information concerning normal subjects' ability to discriminate differences in their pinching force, so the purpose of this study was to evaluate the ability of 24 normal young women to discriminate differences in their self-generated isometric tip and lateral pinching force. Resistance forces of 10, 25, 50, and 75% of known normal maximum pinching force were selected as standards. Subjects were presented a series of paired resistance settings of which the first resistance in each pair was the standard and the second resistance a comparator of some greater amount. This procedure of paired comparisons was continued until subjects' threshold of discrimination between two pinching forces was established. The results indicated that subjects' pinch-force discrimination at the standard of 50% of reported maximum pinching force was significantly better for the tip condition than for the lateral condition. This study has described an instrumentation and the methodology for assessing individuals' ability to discriminate differences in their pinching force at submaximal levels.

Predicting the Western Aphasia Battery Aphasia Quotient.

Administration of the Western Aphasia Battery (WAB) yields a total score termed the Aphasia Quotient (AQ), which is said to reflect the severity of the spoken language deficit in aphasia. This score is a weighted composite of performance on 10 separate WAB subtests. Based on data from 100 patients, all 10 subtests were found to correlate highly with each other and with the AQ, but the score from one subtest, Information Content, was the best predictor of the AQ. Time postonset had no influence on the relationships among the subtests or between the 10 subtests and the AQ. These findings are useful in understanding the Western Aphasia Battery and in interpreting the Aphasia Quotient.

Verbal reaction time patterns in aphasic adults: consideration for apraxia of speech.

Verbal reaction time patterns were compared in aphasic adults presenting anterior and posterior left hemisphere lesions. Reaction Times were measured from simultaneous recording of the subjects' verbal responses and electromyographic activity from three oral-facial sites. Total Reaction Time was fractionated into Premotor Time and Motor Time components to assess latencies associated with motor speech planning and execution. The results suggested that only anterior lesions result in deficits in motor speech planning and/or execution while posterior lesion patients perform no differently than normal. The evidence supports traditional concepts regarding apraxia of speech as being associated with frontal lobe lesions.

Letter imagery deficits in a case of pure apraxic agraphia.

Pure apraxic agraphia is a condition in which motor writing is impaired but limb praxis and nonmotor writing (typing, anagram letters) are preserved. This condition is believed to result from disruption of a parietal lobe graphemic area which generates grapheme representations used to program motor-writing patterns. We report a single case of pure apraxic agraphia in which defective letter imagery was evident. Results of writing and imagery evaluations suggest that the graphemic area may be responsible for generating letter images. In this respect, clinical evaluation of letter imagery abilities in cases of apraxic agraphia may be useful in identifying subtypes of the disorder resulting in a better understanding of the neuropsychological process involved in writing.

Phonological error patterns in developmental verbal dyspraxia.

Phonological error patterns are analyzed in a group of 10 children presenting symptoms consistent with Developmental Verbal Dyspraxia. Results indicate a dominance of "sequentially constrained" errors primarily involving sound and syllable omissions and timing errors. Rank-order correlations among the phonological errors and between phonological errors and developmental indices suggest that these children have a specific expressive language problem dominated by phonological errors of sequential reduction. Interpretation of the data points to a central motor planning deficit. Comparisons are made with other studies depicting neuropsychological deficits in similar children.

Phonological process analysis from spontaneous speech: the influence of sample size.

Phonological process analysis is becoming a popular technique for the evaluation of unintelligible children and adults. Spontaneous speech sampling procedures have been advocated as a representative sampling base for phonological process analysis; however, little research has been reported detailing the parameters of spontaneous samples in reference to this assessment technique. The purpose of the present study was to evaluate the influence of increasing sample size on phonological process analyses from spontaneous speech. Results clearly indicated that samples of 50 words provided descriptive information similar to samples of 100 words. Additional studies are called for to investigate other variables that might influence the results of spontaneous speech analysis.

Interaction of sensory feedback: a child-adult comparison of oral sensory and temporal articulatory function.

Recent studies have demonstrated a systematic increase in lingual sensory thresholds and a temporal articulatory reorganization in subjects speaking under exposure to auditory masking. These data suggest that auditory and lingual sensory feedback systems exist in a balanced interaction specific to the oral articulations involved in speech production. The present study attempted to gain additional information on this proposed interaction. Lingual sensory and temporal articulatory measurements were obtained from 10 adults and 10 children under each of four feedback conditions: (1) normal feedback, (2) exposure to binaural auditory masking during speech, (3) topical application of anesthesia to the lingual dorsum prior to speech, and (4) combined masking and anesthesia. Analysis indicated that children had lower lingual sensory thresholds than adults in all conditions and that they were more susceptible to the disruption of auditory feedback. Also, measurements of durations of vowels indicated no age-related differences with durations in both groups increasing when auditory feedback was impaired.