Estimating the minimal clinically important difference for balance and gait outcome measures in individuals with vestibular disorders

Physical Therapy and Aminopyridine for Downbeat Nystagmus Syndrome: A Case Report

BACKGROUND AND PURPOSE

Individuals with downbeat nystagmus (DBN) syndrome present with DBN, dizziness, blurred vision, and unsteady gait. Pharmacological intervention with 4-aminopyridine (4-AP) may be effective in improving oculomotor function, but there is minimal evidence to date that it improves gait. This suggests the possible benefit of combining pharmacotherapy with physical therapy to maximize outcomes. This case report documents improvements in gait and balance after physical therapy and aminopyridine (AP) in an individual with DBN syndrome.

CASE DESCRIPTION

The patient was a 70-year-old man with a 4-year history of worsening dizziness and imbalance, diagnosed with DBN syndrome. He demonstrated impaired oculomotor function, dizziness, and imbalance, which resulted in falls and limited community ambulation.

INTERVENTION

The patient completed a customized, tapered course of physical therapy over 6 months. Outcome measures included the 10-meter walk test, the Timed Up and Go (TUG), the Dynamic Gait Index (DGI), and the modified clinical test of sensory integration and balance.

OUTCOMES

Improvements exceeding minimal detectable change were demonstrated on the TUG and the DGI. Gait speed on the 10-meter walk test did not change significantly, but the patient was able to use a cane to ambulate in the community and reported no further falls.

DISCUSSION

Controlled studies are needed to explore the potential for AP to augment physical therapy in people with DBN syndrome. Physical therapists are encouraged to communicate with referring medical providers about the use of AP as pharmacotherapy along with physical therapy for individuals with DBN syndrome.

Adherence to customized vestibular rehabilitation therapy: influencing factors and clinical implications in vestibulopathy

Objective

Customized vestibular rehabilitation therapy (CVRT) is an effective treatment approach for various vestibular disorders. However, low adherence significantly limits its efficacy, and factors influencing adherence remain underexplored. This study aimed to identify factors affecting adherence to CVRT across major vestibulopathy categories, including acute unilateral vestibular hypofunction (AUVH), chronic unilateral vestibular hypofunction (CUVH), and bilateral vestibular hypofunction (BVH).

Methods

A retrospective analysis of 90 patients who were prescribed four sessions of CVRT and underwent the therapy was conducted. Patients were classified as adherent (≥3 sessions) or non-adherent (≤2 sessions). Demographic characteristics, baseline questionnaire scores, and vestibular function test (VFT) results were compared. Change in questionnaire scores and VFT results before and after CVRT, as well as mid-treatment follow-up questionnaire scores were analyzed.

Results

Adherence rates were highest in CUVH (86.7%) and lowest in BVH (46.2%). Among patients with AUVH, poor functional reach test scores were significantly associated with lower adherence (p = 0.045). In the CUVH category, patients with mild dizziness in the initial questionnaire were non-adherent (p = 0.019). CVRT improved subjective dizziness symptoms and VFT parameters, with the greatest gains observed in AUVH. However, no significant differences in symptom improvement were found between adherent and non-adherent patients. Patients whose symptoms improved rapidly to a mild degree after starting the CVRT were more likely to be non-adherent, with this tendency being especially pronounced in those with AUVH.

Conclusion

Adherence to CVRT varies by vestibulopathy category and is influenced by baseline symptom severity. Tailoring CVRT strategies based on individual clinical profiles may enhance adherence and optimize therapeutic outcomes.

Minimal Clinically Important Difference of Vestibular Migraine Patient Assessment Tool and Handicap Inventory (VM-PATHI)

OBJECTIVE

To calculate the minimal clinically important difference (MCID) for the Vestibular Migraine Patient Assessment Tool and Handicap Inventory (VM-PATHI).

STUDY DESIGN

Prospective cohort study.

SETTING

A single tertiary care balance and falls center.

METHODS

Fifty-three subjects meeting Barany Society criteria for vestibular migraine (VM) or probable VM were included and divided into 3 treatment groups. Treatment was not standardized, instead, management was decided individually between each patient and their provider. All subjects completed VM-PATHI before and after intervention. A Global Rating of Change (GRoC) questionnaire was also completed following intervention. Anchor-based methods, using a GRoC questionnaire, were utilized to estimate the MCID that produced the highest sensitivity and specificity on a receiver operating characteristic (ROC) curve.

RESULTS

Forty-three subjects were classified as responders and 10 were classified as nonresponders. The mean VM-PATHI pretreatment score minus the posttreatment score between the responders (mean = 14, SD 13) and nonresponders (mean = 4 SD = 12) was statistically significant (mean difference = 10, 95% confidence interval, CI [1, 20], P = .03). The VM-PATHI score change cutoff that best differentiated between responders and nonresponders was a VM-PATHI change of 6. Thus, the MCID was defined as a change of 6 points (sensitivity = 72%, specificity = 70%). The area under the ROC curve was 0.89, 95% CI [0.80, 0.98], which demonstrates an excellent ability for the VM-PATHI score change to discriminate between responders and nonresponders. The average change in VM-PATHI scores was 9 points (SD 11) for those with "a little better" rating on the GRoC, 14 points (SD 14) for those with a "moderately better" rating, and 20 points (SD 13) for those with a "very much better" rating.

CONCLUSION

Patients with VM are likely to demonstrate clinical improvement if their VM-PATHI score decreases by 6 or more.

Three-dimensional exergaming conjunction with vestibular rehabilitation in individuals with Benign Paroxysmal Positional Vertigo: A feasibility randomized controlled study

BACKGROUND

To examine the effectiveness of 3D (dimensional)-vestibular rehabilitation therapy (VRT) on gait, balance problems, processing time speed and subjective complaints in patients with Benign Paroxysmal Positional Vertigo (BPPV) compared to a control group (CG). This study aimed to test the feasibility of virtual reality-based 3D exergaming conjunction with vestibular rehabilitation.

METHODS

Twenty-two patients with BPPV (negative DixHallpike/Roll test results, existing dizziness/balance complaints) were randomly allocated to the study group (SG, n:11 3D-VRT) or Control group (CG n:11, no exercise-rehabilitation) for 8 week. The SG performed 3D-VRT for 45 to 50 min/d, 3 times/wk, and the CG did receive only Canalith Repositioning Maneuver (CRM). CRM was applied in both groups before the study. Outcome measures included 10-Meter-Walk-Test (10-MWT) (with/without head turns), Dynamic Gait Index (DGI), Choice-Stepping-Reaction-Time-ped (CSRT-MAT), Fullerton Advanced Balance Scale (FAB), and Visual Analog Scale (VAS).

RESULTS

The SG showed significantly improvement in 10-MWT without (p5 = 0.00,η2 = 0.49), with horizontal (p5 = 0.00,η2 = 0.57),vertical (p5 = 0.01,η2 = 0.48) head turns, DGI (p5 = 0.00,η2 = 0.74), CSRT-MAT, FAB (p5 = 0.00,η2 = 0.78) and VAS-dizziness (p5 = 0.00,η2 = 0.65), VAS-balance problem (p5 = 0.00,η2 = 0.43), VAS-fear of falling (p5 = 0.00,η2 = 0.42) compared to the CG.

CONCLUSION

The 3D-VRT were effective in improving gait, balance, processing speed and resolving the subjective complaints in BPPV. The 3D-VRT method is feasible for patients who suffer from residual dizziness or balance complaints after CRM. Furthermore, the 3D-VRT is more accessible and less expensive than other virtual reality applications, which may facilitate further research or clinical use.

Investigating health disparities in vestibular rehabilitation

BACKGROUND

Health disparities (HD) impact care delivery and health outcomes in individuals with vestibular disorders (IVD).

OBJECTIVE

The purpose of this study is to identify whether health disparities (HD) exist in Vestibular Rehabilitation (VR) between individuals identifying as Caucasians or racial or ethnic minorities (REM).

METHODS

This study was a retrospective chart review of IVD who attended outpatient VR between 1/2014 and 9/2020. Data recorded included age, gender, race/ethnicity, vestibular diagnosis, VR interventions, and pre-post outcome measures such as Dizziness Handicap Inventory (DHI), and Activities-Specific Balance Confidence Scale (ABC), Gait speed (GS), and Functional Gait Assessment (FGA). Chi-squared tests, one-tailed, and two-tailed t-tests (α= 0.05) were utilized to compare Caucasian and REM groups.

RESULTS

Three hundred and forty-three charts (N = 343) met inclusion/exclusion criteria. REM demonstrated higher median DHI scores (46 vs. 38, p = 0.008) and lower ABC scores (53.10% vs. 66.30%, p < 0.001) at VR evaluation compared to Caucasians. There were no statistically significant differences in DHI, ABC, FGA, and GS scores between Caucasians and REM at discharge.

CONCLUSIONS

VR was able to equalize HD in DHI and ABC which initially existed between REM and Caucasians. VR therapists should work with public health and policy researchers to improve access to VR.

Item Level Psychometrics of the Dizziness Handicap Inventory in Vestibular Migraine and Meniere's Disease

OBJECTIVES

Evaluate the measurement properties of the Dizziness Handicap Inventory (DHI) using item response theory in patients diagnosed with vestibular migraine (VM) and Meniere's disease (MD).

DESIGN

One hundred twenty-five patients diagnosed with VM and 169 patients diagnosed with MD by a vestibular neurotologist according to the Bárány Society criteria in two tertiary multidisciplinary vestibular clinics and who completed the DHI at their initial visit, were included in the study. The DHI (total score and individual items) was analyzed using the Rasch Rating Scale model for patients in each subgroup, VM and MD, and as a whole group. The following categories were assessed: rating-scale structure, unidimensionality, item and person fit, item difficulty hierarchy, person-item match, and separation index, standard error of measurement, and minimal detectable change (MDC).

RESULTS

Patients were predominantly female (80% of the VM subgroup and 68% of the MD subgroup) with a mean age of 49.9 ± 16.5 years and 54.1 ± 14.2 years, respectively. The mean total DHI score for the VM group was 51.9 ± 22.3 and for the MD group was 48.5 ± 26.6 ( p > 0.05). While neither all items nor the separate constructs met all criteria for unidimensionality (i.e., items measuring a single construct), post hoc analysis showed that the all-item analysis supported a single construct. All analyses met the criterion for showing a sound rating scale and acceptable Cronbach's alpha (≥0.69). The all-item analysis showed the most precision, separating the samples into three to four significant strata. The separate-construct analyses (physical, emotional, and functional) showed the least precision, separated the samples into less than three significant strata. Regarding MDC, the MDC remained consistent across the analyses of the different samples; approximately 18 points for the full analyses and approximately 10 points for the separate construct (physical, emotional, and functional).

CONCLUSIONS

Our evaluation of the DHI using item response theory shows that the instrument is psychometrically sound and reliable. The all-item instrument fulfills criteria for essential unidimensionality but does seem to measure multiple latent constructs in patients with VM and MD, which has been reported in other balance and mobility instruments. The current subscales did not show acceptable psychometrics, which is in line with multiple recent studies favoring the use of the total score. The study also shows that the DHI is adaptable to episodic recurrent vestibulopathies. The total score shows better precision and separation of subjects in up to four strata compared to the separate construct that separate subjects into less than three strata. The measurement error smallest detectable change was found in our analysis to be 18 points, which means any change in the DHI of less than 18 points is not likely to be clinically significant. The minimal clinically important difference remains indeterminate.

Contextual sensory integration training vs. traditional vestibular rehabilitation: a pilot randomized controlled trial

BACKGROUND

We created a clinical virtual reality application for vestibular rehabilitation. Our app targets contextual sensory integration (C.S.I.) where patients are immersed in safe, increasingly challenging environments while practicing various tasks (e.g., turning, walking). The purpose of this pilot study was to establish the feasibility of a randomized controlled trial comparing C.S.I. training to traditional vestibular rehabilitation.

METHODS

Thirty patients with vestibular dysfunction completed the Dizziness Handicap Inventory (DHI), Activities-Specific Balance Confidence Scale (ABC), Visual Vertigo Analog Scale (VVAS), Functional Gait Assessment (FGA), Timed-Up-and-Go (TUG), and Four-Square Step Test (FSST). Following initial assessment, the patients were randomized into 8 weeks (once per week in clinic + home exercise program) of traditional vestibular rehabilitation or C.S.I. training. Six patients had to stop participation due to the covid-19 pandemic, 6 dropped out for other reasons (3 from each group). Ten patients in the traditional group and 8 in the C.S.I group completed the study. We applied an intention to treat analysis.

RESULTS

Following intervention, we observed a significant main effect of time with no main effect of group or group by time interaction for the DHI (mean difference - 18.703, 95% CI [-28.235, -9.172], p = 0.0002), ABC (8.556, [0.938, 16.174], p = 0.028), VVAS, (-13.603, [-25.634, -1.573], p = 0.027) and the FGA (6.405, [4.474, 8.335], p < 0.0001). No changes were observed for TUG and FSST.

CONCLUSION

Patients' symptoms and function improved following either vestibular rehabilitation method. C.S.I training appeared comparable but not superior to traditional rehabilitation.

TRIAL REGISTRATION

This study (NCT04268745) was registered on clincaltrials.gov and can be found at https://clinicaltrials.gov/ct2/show/NCT04268745 .

Effects of contact/collision sport history on gait in early- to mid-adulthood

BACKGROUND

To determine the effect of contact/collision sport participation on measures of single-task (ST) and dual-task (DT) gait among early- to middle-aged adults.

METHODS

The study recruited 113 adults (34.88 ± 11.80 years, (mean ± SD); 53.0% female) representing 4 groups. Groups included (a) former non-contact/collision athletes and non-athletes who are not physically active (n = 28); (b) former non-contact/collision athletes who are physically active (n = 29); (c) former contact/collision sport athletes who participated in high-risk sports and are physically active (n = 29); and (d) former rugby players with prolonged repetitive head impact exposure history who are physically active (n = 27). Gait parameters were collected using inertial measurement units during ST and DT gait. DT cost was calculated for all gait parameters (double support, gait speed, and stride length). Groups were compared first using one-way analysis of covariance. Then a multiple regression was performed for participants in the high-risk sport athletes and repetitive head impact exposure athletes groups only to predict gait outcomes from contact/collision sport career duration.

RESULTS

There were no significant differences between groups on any ST, DT, or DT cost outcomes (p > 0.05). Contact/collision sport duration did not predict any ST, DT, or DT cost gait outcomes.

CONCLUSION

Years and history of contact/collision sport participation does not appear to negatively affect or predict neurobehavioral function in early- to mid-adulthood among physically active individuals.

Team Approach to Delayed Pediatric Vestibular Diagnosis: A Case Study

BACKGROUND AND PURPOSE

This report highlights the challenges of diagnosing pediatric vestibular neuritis following dental treatment and addressing fear avoidance behaviors.

CASE DESCRIPTION

An 11-year-old boy came to physical therapy with vestibular dysfunction following dental treatment that was unable to be diagnosed by emergency department staff. The participant received multispecialty treatment for 6 weeks.

MEASUREMENTS

Computerized Dynamic Posturography, Limits of Stability, Dizziness Handicap Inventory, Functional Gait Assessment, Dynamic Visual Acuity, and Modified Clinical Test of Sensory Interaction on Balance.

OUTCOMES

Most notable improvements were seen in Limits of Stability and Computerized Dynamic Posturography. The participant made a full return to school and sport.

CONCLUSIONS

The difficulty of pediatric vestibular neuritis diagnosis led to fear avoidance behaviors that were addressed by a collaborative specialty approach.

WHAT THIS ADDS TO EVIDENCE

This is the first documented case of pediatric vestibular neuritis as a complication of a dental procedure with intervention focused on fear avoidance behaviors.

The minimal clinically important difference for gait speed in significant unilateral vestibular hypofunction after vestibular rehabilitation

Gait speed is a valid measure of both physical function and vestibular health. Vestibular rehabilitation is useful to improve gait speed for patients with vestibular hypofunction, yet there is little data to indicate how changes in gait speed reflect changes in patient-reported health outcomes. We determined the minimal clinically important difference in the gait speed of patients with unilateral vestibular hypofunction, mostly due to deafferentation surgery, as anchored to the Dizziness Handicap Index and the Activities Balance Confidence scale, validated using regression analysis, change difference, receiver-operator characteristic curve, and average change methods. After six weeks of vestibular rehabilitation, a change in gait speed from 0.20 to 0.34 m/s with 95% confidence was required for the patients to perceive a significant reduction in perception of dizziness and improved balance confidence.