Exploring the relationship between sleep apnea and vestibular symptoms following traumatic brain injury.

BACKGROUND: Traumatic brain injury (TBI) is a complex health problem in military veterans and service members (V/SM) that often involves comorbid vestibular impairment. Sleep apnea is another comorbidity that may exacerbate, and/or be exacerbated by, vestibular dysfunction. OBJECTIVE: To examine the relationship between sleep apnea and vestibular symptoms in V/SM diagnosed with TBI of any severity. DESIGN: Multicenter cohort study; cross-sectional sample. SETTING: In-patient TBI rehabilitation units within five Veterans Affairs (VA) Polytrauma Rehabilitation Centers. PARTICIPANTS: V/SM with a diagnosis of TBI (N = 630) enrolled in the VA TBI Model Systems study. INTERVENTION: Not applicable. METHODS: A multivariable regression model was used to evaluate the association between sleep apnea and vestibular symptom severity while controlling for relevant covariates, for example, posttraumatic stress disorder (PTSD). MAIN OUTCOME MEASURES: Lifetime history of sleep apnea was determined via best source reporting. Vestibular disturbances were measured with the 3-item Vestibular subscale of the Neurobehavioral Symptom Inventory (NSI). RESULTS: One third (30.6%) of the sample had a self-reported sleep apnea diagnosis. Initial analysis showed that participants who had sleep apnea had more severe vestibular symptoms (M = 3.84, SD = 2.86) than those without sleep apnea (M = 2.88, SD = 2.67, p < .001). However, when the data was analyzed via a multiple regression model, sleep apnea no longer reached the threshold of significance as a factor associated with vestibular symptoms. PTSD severity was shown to be significantly associated with vestibular symptoms within this sample (p < .001). CONCLUSION: Analysis of these data revealed a relationship between sleep apnea and vestibular symptoms in V/SM with TBI. The significance of this relationship was affected when PTSD symptoms were factored into a multivariable regression model. However, given that the mechanisms and directionality of these relationships are not yet well understood, we assert that in terms of clinical relevance, providers should emphasize screening for each of the three studied comorbidities (sleep apnea, vestibular symptoms, and PTSD).

Use of the knowledge to action model improved physical therapist adherence to a common clinical practice guideline across multiple settings: a multisite case series.

BACKGROUND: When a new guideline is published there is a need to understand how its recommendations can best be implemented in real-world practice. Yet, guidelines are often published with little to no roadmap for organizations to follow to promote adherence to their recommendations. The purpose of this study was to evaluate the impact of using a common process model to implement a single clinical practice guideline across multiple physical therapy clinical settings. METHODS: Five organizationally distinct sites with physical therapy services for patients with peripheral vestibular hypofunction participated. The Knowledge to Action model served as the foundation for implementation of a newly published guideline. Site leaders conducted preliminary gap surveys and face-to-face meetings to guide physical therapist stakeholders' identification of target-behaviors for improved guideline adherence. A 6-month multimodal implementation intervention included local opinion leaders, audit and feedback, fatigue-resistant reminders, and communities of practice. Therapist adherence to target-behaviors for the 6 months before and after the intervention was the primary outcome for behavior change. RESULTS: Therapist participants at all sites indicated readiness for change and commitment to the project. Four sites with more experienced therapists selected similar target behaviors while the fifth, with more inexperienced therapists, identified different goals. Adherence to target behaviors was mixed. Among four sites with similar target behaviors, three had multiple areas of statistically significantly improved adherence and one site had limited improvement. Success was most common with behaviors related to documentation and offering patients low technology resources to support home exercise. A fifth site showed a trend toward improved therapist self-efficacy and therapist behavior change in one provider location. CONCLUSIONS: The Knowledge to Action model provided a common process model for sites with diverse structures and needs to implement a guideline in practice. Multimodal, active interventions, with a focus on auditing adherence to therapist-selected target behaviors, feedback in collaborative monthly meetings, fatigue-resistant reminders, and developing communities of practice was associated with long-term improvement in adherence. Local rather than external opinion leaders, therapist availability for community building meetings, and rate of provider turnover likely impacted success in this model. TRIAL REGISTRATION: This study does not report the results of a health care intervention on human participants.

Sensory Phenotypes for Balance Dysfunction After Mild Traumatic Brain Injury.

BACKGROUND AND OBJECTIVES: Recent team-based models of care use symptom subtypes to guide treatments for individuals with chronic effects of mild traumatic brain injury (mTBI). However, these subtypes, or phenotypes, may be too broad, particularly for balance (e.g., 'vestibular subtype'). To gain insight into mTBI-related imbalance we 1) explored whether a dominant sensory phenotype (e.g., vestibular impaired) exists in the chronic mTBI population, 2) determined the clinical characteristics, symptomatic clusters, functional measures, and injury mechanisms that associate with sensory phenotypes for balance control in this population, and 3) compared the presentations of sensory phenotypes between individuals with and without previous mTBI. METHODS: A secondary analysis was conducted on the Long-Term Impact of Military-Relevant Brain Injury Consortium - Chronic Effects of Neurotrauma Consortium. Sensory ratios were calculated from the Sensory Organization Test, and individuals were categorized into one of eight possible sensory phenotypes. Demographic, clinical, and injury characteristics were compared across phenotypes. Symptoms, cognition, and physical function were compared across phenotypes, groups, and their interaction. RESULTS: Data from 758 Service Members and Veterans with mTBI and 172 with no lifetime history of mTBI were included. Abnormal visual, vestibular, and proprioception ratios were observed in 29%, 36%, and 38% of people with mTBI, respectively, with 32% exhibiting more than one abnormal sensory ratio. Within the mTBI group, global outcomes (p<0.001), self-reported symptom severity (p<0.027), and nearly all physical and cognitive functioning tests (p<0.027) differed across sensory phenotypes. Individuals with mTBI generally reported worse symptoms than their non-mTBI counterparts within the same phenotype (p=0.026), but participants with mTBI in the Vestibular-Deficient phenotype reported lower symptom burdens than their non-mTBI counterparts [e.g., mean(SD) Dizziness Handicap Inventory = 4.9(8.1) for mTBI vs. 12.8(12.4) for non-mTBI, group*phenotype interaction p<0.001]. Physical and cognitive functioning did not differ between groups after accounting for phenotype. DISCUSSION: Individuals with mTBI exhibit a variety of chronic balance deficits involving heterogeneous sensory integration problems. While imbalance when relying on vestibular information is common, it is inaccurate to label all mTBI-related balance dysfunction under the 'vestibular' umbrella. Future work should consider specific classification of balance deficits, including specific sensory phenotypes for balance control.

Use of Stakeholder Feedback to Develop an App for Vestibular Rehabilitation-Input From Clinicians and Healthy Older Adults.

Close to half people over 60 years of age experience vestibular dysfunction. Although vestibular rehabilitation has been proven effective in reducing dizziness and falls in older adults, adherence to exercise programs is a major issue and reported to be below 50%. Therefore, this research aimed to develop an app with gaming elements to improve adherence to exercises that are part of vestibular rehabilitation, and to provide feedback to increase the accuracy during exercise performance. A clinician-informed design was used where five physical therapists were asked identical questions about the exercises they would like to see in the app, including their duration and frequency. Games were developed to train the vestibulo-ocular (VOR) reflex using VOR and gaze shifting exercises; and to train the vestibulo-spinal system using weight shifting and balance exercises. The games were designed to progress from simple to more complex visuals. The games were controlled by an Inertial Measurement Unit placed on the head or anterior waist. The app was tested on ten healthy females (69.1 ± 5.1 years) with no prior history of vestibular dysfunction or complaints of dizziness. Participants completed gaze stabilization and balance exercises using the app and provided feedback on the user interface, ease of use, usefulness and enjoyment using standardized questionnaires and changes they would like to see in the form of open-ended questions. In general, participants reported that they found the app easy to use, the user interface was friendly, and they enjoyed playing the games due to the graphics and colors. They reported that the feedback provided during the exercise session helped them recognize their mistakes and motivated them to do better. However, some elements of the app were frustrating due to incomplete instructions and inability to distinguish game objects due to insufficient contrast. Feedback received will be implemented in a revised version which will be trialed in older adults with dizziness due to vestibular hypofunction. We have demonstrated that the "Vestibular AppTM" created for rehabilitation with gaming elements was found to be enjoyable, useful, and easy to use by healthy older adults. In the long term, the app may increase adherence to vestibular rehabilitation.