Changes in cognitive function in patients with intractable dizziness following vestibular rehabilitation

Association of Alzheimer's Disease With Peripheral Vestibular Disorder: A Case-Control Study

OBJECTIVES

Vestibular disorders can impact cognitive domains, including spatial orientation and memory, which are also affected in Alzheimer's disease. This study aimed to examine the association between Alzheimer's disease and a prior diagnosis of peripheral vestibular disorders in the elderly Taiwanese population.

METHODS

The case-control study sample was retrieved from Taiwan's Longitudinal Health Insurance Database 2010. We included 3138 cases with Alzheimer's disease and 9414 propensity-matched controls. We conducted multivariable logistic regression modeling to investigate the association between Alzheimer's disease and a prior diagnosis of peripheral vestibular disorders after accounting for sociodemographic characteristics and medical comorbidities including diabetes, coronary heart disease, hypertension, hyperlipidemia, and hearing loss.

RESULTS

The results revealed a statistically significant difference in the prevalence of prior peripheral vestibular disorders between patients with Alzheimer's disease and controls; 20.6% among patients with Alzheimer's disease and 11.4% among controls (p < 0.001). Multivariable logistic regression analysis found that patients with Alzheimer's disease were twice as likely as controls to have had a prior diagnosis of peripheral vestibular disorders, adjusted odds ratio 2.040 (95% confidence interval: 1.829-2.274).

CONCLUSIONS

The findings suggest the possibility of shared or related pathophysiological pathways in Alzheimer's disease and vestibular dysfunction disorders.

LEVEL OF EVIDENCE

3 Laryngoscope, 2024.

Vestibular dysfunction in Parkinson's disease: a neglected topic

Dizziness and postural instability are frequently observed symptoms in patient with Parkinson's disease (PD), potentially linked to vestibular dysfunction. Despite their significant impact on quality of life, these symptoms are often overlooked and undertreated in clinical practice. This review aims to summarize symptoms associated with vestibular dysfunction in patients with PD and discusses vestibular-targeted therapies for managing non-specific dizziness and related symptoms. We conducted searches in PubMed and Web of Science using keywords related to vestibular dysfunction, Parkinson's disease, dizziness, and postural instability, alongside the reference lists of relevant articles. The available evidence suggests the prevalence of vestibular dysfunction-related symptoms in patients with PD and supports the idea that vestibular-targeted therapies may be effective in improving PD symptoms.

Cognition in vestibular disorders: state of the field, challenges, and priorities for the future

Vestibular disorders are prevalent and debilitating conditions of the inner ear and brain which affect balance, coordination, and the integration of multisensory inputs. A growing body of research has linked vestibular disorders to cognitive problems, most notably attention, visuospatial perception, spatial memory, and executive function. However, the mechanistic bases of these cognitive sequelae remain poorly defined, and there is a gap between our theoretical understanding of vestibular cognitive dysfunction, and how best to identify and manage this within clinical practice. This article takes stock of these shortcomings and provides recommendations and priorities for healthcare professionals who assess and treat vestibular disorders, and for researchers developing cognitive models and rehabilitation interventions. We highlight the importance of multidisciplinary collaboration for developing and evaluating clinically relevant theoretical models of vestibular cognition, to advance research and treatment.

Physical Health and Mental Fatigue Disability Associated with Long COVID: Baseline Results from a US Nationwide Cohort

BACKGROUND

Persistent symptoms after severe acute respiratory disease coronavirus 2 (SARS-COV-2; long COVID) occur in 10%-55% of individuals, but the impact on daily functioning and disability remains unquantified.

METHODS

To characterize disability associated with long COVID, we analyzed baseline data from an online, US-based cohort study. Adult participants included those reporting a history of COVID-19 (n = 8874) or never having COVID-19 (n = 633) without prior disability. The main outcomes were self-reported physical mobility, instrumental activities of daily living (IADL), and mental fatigue disability, assessed by measuring 5 disability components: difficulty walking a quarter mile or climbing 10 stairs (mobility), difficulty doing light or heavy housework (IADL), and Wood Mental Fatigue Inventory score (mental fatigue).

RESULTS

Of 7926 participants with long COVID, 65% were classified with at least one disability, as compared with 6% and 14% for resolved COVID and no COVID, respectively. Additionally, 22% were classified as disabled in all 3 categories. Age, prior comorbidity, increased body mass index, female sex, COVID-19 hospitalization, non-white/multi-race were associated with higher disability burden. Dizziness and heavy limbs at infection were associated with disability regardless of hospitalization. Dyspnea and tremors were associated with disability in non-hospitalized individuals. Vaccination was protective against disability.

CONCLUSIONS

We observed a high burden of new disability associated with long COVID, which has serious implications for individual and societal health. Longitudinal evaluation of COVID-19 patients is necessary to identify patterns of recovery and treatment options.

Dizziness, psychological disorders and cognitive decline

INTRODUCTION

Dizziness is a common disorder, particularly among the elderly population. Aim of this paper was to revise the current concepts surrounding the relationship between dizziness, psychological disorders and cognitive decline.

EVIDENCE ACQUISITION

This is a PRISMA-compliant systematic review, including observational studies in people with dizziness. Database inception, Medline/Cochrane/Embase/Web of Science/Scopus/NHS evidence were searched until October 30, 2019.

EVIDENCE SYNTHESIS

Overall 22 studies, and 65,730 participants were included. Eleven studies were cross-sectional, 7 cross-sectional controlled, 2 prospective case-control, 1 retrospective case series, and 1 cohort study. The persistence of vestibular impairment (for 6 months or more) was correlated to the presence of psychological disorders affecting patient's Quality of Life and causing social anxiety, particularly in some conditions such as Ménière's disease. Interestingly, vestibular loss has been also correlated to cognitive impairment, with certain vestibular dysfunctions reported to be more prevalent in cognitive impaired individuals.

CONCLUSIONS

The current literature suggests that there is an association between vestibular function, psychological disorders and cognitive functions. The findings from this review could be useful in informing on the need for a multidimensional diagnostic and rehabilitative programs for patients with dizziness. More studies could explore the role of counseling or behavioral therapy with an aim to reduce the perceived dizziness-related disability.

Physical and mental health disability associated with long-COVID: Baseline results from a US nationwide cohort

Importance

Persistent symptoms after SARS-COV-2 infection, or long-COVID, may occur in anywhere from 10-55% of those who have had COVID-19, but the extent of impact on daily functioning and disability remains unquantified.

Objective

To characterize physical and mental disability associated with long-COVID.

Design

Cross-sectional analysis of baseline data from a cohort study.

Setting

Online US nationwide survey.

Participants

Adults 18 years of age and older who live in the US who either report a history of COVID-19 illness (n=8,874) or report never having had COVID-19 (n=633).

Main Outcome and Measures

Self-reported mobility disability (difficulty walking a quarter of a mile and/or up 10 stairs, instrumental activities of daily living [IADL] disability (difficulty doing light or heavy housework), and mental fatigue as measured by the Wood Mental Fatigue Inventory (WMFI).

Results

Of 7,926 participants with long-COVID, the median age was 45 years, 84% were female, 89% self-reported white race, and 7.4% self-reported Hispanic/Latino ethnicity. Sixty-five percent of long-COVID participants were classified as having at least one disability, compared to 6% of those with resolved-COVID (n=948) and 14% of those with no-COVID (n=633). Of long-COVID participants, about 1% and 5% were classified as critically physically disabled or mentally fatigued, respectively. Age, prior comorbidity, increased BMI, female gender, hospitalization for COVID-19, non-white race, and multi-race were all associated with significantly higher disability burden. Dizziness at the time of infection (33% non-hospitalized, 39% hospitalized) was associated with all five disability components in both hospitalized and non-hospitalized groups. Heavy limbs, dyspnea, and tremors were associated with four of the five components of disability in the non-hospitalized group, and heavy limbs was associated with four of the five components in the hospitalized group. Vaccination was protective against development of disability.

Conclusion and Relevance

We observed a high burden of physical and mental disability associated with long-COVID which has serious implications for individual and societal health that may be partially mitigated by vaccination. Longitudinal characterization and evaluation of COVID-19 patients is necessary to identify patterns of recovery and treatment options.

Associations of Bilateral Vestibulopathy With Cognition in Older Adults Matched With Healthy Controls for Hearing Status

Question

Is bilateral vestibulopathy (BV) associated with cognitive function in older adults?

Findings

In this cross-sectional study including 34 participants with BV and 34 age-, sex-, and hearing performance–matched controls, participants with BV had worse cognitive function in general, which was most pronounced in the subdomains of immediate memory, visuospatial cognition, and attention.

Meaning

These findings support existing evidence on an association between vestibular loss and cognitive impairment.

Importance

Recent literature suggests there may be a significant effect of the vestibular system on cognition and visuospatial processing. Given the increasing prevalence of dementia and individuals at risk for it, exploring possible modifiable risk factors, including vestibular dysfunction, is vital.

Objectives

To explore the association of bilateral vestibulopathy (BV) with cognitive function in older adults, taking hearing status into account, and to explore multiple vestibular characteristics and their potential associations with cognition in patients with BV.

Design, Setting, and Participants

This cross-sectional study assessed older adults (age 55-84 years) with diagnosed BV from a single center using baseline measurements from the Gehoor, Evenwicht en Cognitie (GECKO) study, an ongoing prospective longitudinal cohort study. Each participant was individually matched with a healthy control based on age, sex, and hearing performance. Data were analyzed in January 2022.

Main Outcomes and Measures

The primary outcome measure was cognition, measured by the Repeatable Battery for the Assessment of Neuropsychological Status for Hearing-Impaired Individuals (RBANS-H).

Results

A total of 68 patients were assessed, including 34 patients with BV (mean [SD] age, 63.3 [6.0] years; 18 [53%] men) matched with 34 control individuals without BV. Overall, participants with BV had a clinically meaningful lower score on the RBANS-H total scale compared with those without BV (mean [SD] score, 98.62 [12.70] vs 105.91 [11.03]). This decline was most pronounced in the subdomains of immediate memory (mean [SD] score, 107.74 [10.66] vs 112.26 [10.66]), visuospatial cognition (mean [SD] score, 90.06 [13.34] vs 100.47 [13.91]), and attention (mean [SD] score, 94.79 [16.39] vs 102.06 [12.97]). There were no differences in language or delayed memory subdomains. Within the BV population, 1 vestibular parameter (the Performance-Oriented Mobility Assessment, in particular the balance subscale) was associated with lower cognitive scores (r₃₂ = 0.51; 95% CI, 0.20 to 0.72; η² = 0.26). Other vestibular parameters, including measurements of the peripheral vestibular end organ and questionnaires, showed no association.

Conclusions and Relevance

These findings suggest there was an association between vestibular loss and cognitive impairment. Further research on the causal mechanisms underlying this association and the possible impact of vestibular rehabilitation on cognition is needed.

Resting-State Electroencephalography and P300 Evidence: Age-Related Vestibular Loss as a Risk Factor Contributes to Cognitive Decline

Background:

In recent years, there have been several meaningful advances in the understanding of the cognitive effects of vestibular loss. However, there has not yet been an investigation exploring the early biomarkers of preclinical cognitive decline in individuals with age-related vestibular loss.

Objective:

We aim to explore the “early biomarkers” of preclinical cognitive decline based on altered cortical activity (resting-state electroencephalography (EEG) and P300) with a multichannel EEG system in individuals with age-related vestibular loss.

Method:

This is a case-control study. A total of 21 patients with age-related vestibular loss (66.50±5.79 years, 13 [62% ] females), 19 patients with cognitive decline (68.42±5.82 years, 13 [68% ] females), and 21 age- and sex-matched healthy controls were recruited. All participants underwent a comprehensive battery of neuropsychological tests, audio-vestibular evaluations, resting-state EEG and P300 recordings.

Results:

Significant visuo-spatial, executive, and attention hypofunction were observed in the age-related vestibular group, reflected by decreased subscale scores. Reduced gamma functional connectivity between the right cuneus (Brodmann area 19, BA19) and the left superior parietal gyrus (BA7) was observed in both the age-related vestibular group and the cognitive impairment group. Smaller P300 amplitudes were observed in the age-related vestibular group (1.43±3.69μV) and cognitive impairment group (1.15±4.24μV) than in the healthy control group (3.97±2.38μV).

Conclusion:

Decreased P300 amplitude and functional connectivity between the right BA19 and the left BA7 were “early biomarkers” observed in individuals with age-related vestibular loss; these biomarkers may contribute to visuospatial, executive, and attention hypofunction.

Hearing loss versus vestibular loss as contributors to cognitive dysfunction

In the last 5 years, there has been a surge in evidence that hearing loss (HL) may be a risk factor for cognitive dysfunction, including dementia. At the same time, there has been an increase in the number of studies implicating vestibular loss in cognitive dysfunction. Due to the fact that vestibular disorders often present with HL and other auditory disorders such as tinnitus, it has been suggested that, in many cases, what appears to be vestibular-related cognitive dysfunction may be due to HL (e.g., Dobbels et al. Front Neurol 11:710, 2020). This review analyses the studies of vestibular-related cognitive dysfunction which have controlled HL. It is suggested that despite the fact that many studies in the area have not controlled HL, many other studies have (~ 19/44 studies or 43%). Therefore, although there is certainly a need for further studies controlling HL, there is evidence to suggest that vestibular loss is associated with cognitive dysfunction, especially related to spatial memory. This is consistent with the overwhelming evidence from animal studies that the vestibular system transmits specific types of information about self-motion to structures such as the hippocampus.

Short Vestibular and Cognitive Training Improves Oral Reading Fluency in Children with Dyslexia

(1) Background: This study explored the effect of short vestibular and cognitive training on the reading speed in dyslexic children. (2) Methods: The reading speed was evaluated by using a reading test (Évaluation de la Lecture en FluencE, ELFE) in a crossover design before (baseline) and after vestibular training (post VT) and no vestibular training (post no VT). Nineteen dyslexic children (9.48 ± 0.15 years) participated in the study. The vestibular and cognitive training (software developed by BeonSolution S.r.l.) consisted in four exercises presented on a Wacom tablet 10″ done for 16 min per session two times per week for four weeks; each exercise was composed of eight levels with increased difficulty. (3) Results: Following vestibular and cognitive training, dyslexic children increased their reading speed; interestingly, such an increase persisted at least one month after training. (4) Conclusions: Vestibular and cognitive training could improve the vestibular network, which is well known for being involved in several cognition functions leading to reading improvement in dyslexic children. Adaptive mechanisms could be responsible for maintaining such improvement for at least one month.

The role of nutrition in space exploration: Implications for sensorimotor, cognition, behavior and the cerebral changes due to the exposure to radiation, altered gravity, and isolation/confinement hazards of spaceflight

Multi-year crewed space exploration missions are now on the horizon; therefore, it is important that we understand and mitigate the physiological effects of spaceflight. The spaceflight hazards-radiation, isolation, confinement, and altered gravity-have the potential to contribute to neuroinflammation and produce long-term cognitive and behavioral effects-while the fifth hazard, distance from earth, limits capabilities to mitigate these risks. Accumulated evidence suggests that nutrition has an important role in optimizing cognition and reducing the risk of neurodegenerative diseases caused by neuroinflammation. Here we review the nutritional perspective of how these spaceflight hazards affect the astronaut's brain, behavior, performance, and sensorimotor function. We also assess potential nutrient/nutritional countermeasures that could prevent or mitigate spaceflight risks and ensure that crewmembers remain healthy and perform well during their missions. Just as history has taught us the importance of nutrition in terrestrial exploration, we must understand the role of nutrition in the development and mitigation of spaceflight risks before humans can successfully explore beyond low-Earth orbit.

Usefulness of postural sway spectral analysis in the diagnostic route and clinical integration of cervicogenic and vestibular sources of dizziness: A cross-sectional preliminary study

BACKGROUND

Posturography power spectra (PS) implementation has been proven to discriminate between sensory inputs detriment of vestibular and proprioceptive origin.

OBJECTIVE

To deepen the role of posturography testing in the diagnostic route of dizzy conditions, by comparing two groups of patients -93 affected by cervicogenic dizziness (CGD) and 72 by unilateral vestibular hypofunction (UVH) -with a group of 98 age- and gender-matched healthy subjects, serving as control group (CON).

METHODS

All participants underwent otoneurological testing including video head impulse test (vHIT) and posturography testing with PS analysis. They also filled in Dizziness Handicap Inventory (DHI), Tampa Scale for Kinesiophobia and Hospital Anxiety and Depression Scale questionnaires.

RESULTS

UVH and CGD patients were found to have significant increase in vestibular- and proprioceptive-related PS values when compared with CON. Receiver operating characteristic curves found PS values to reliably discriminate both groups from CON. Positive and negative correlations were respectively found between vestibular-/proprioceptive-related PS domain and DHI in both groups and between PS and vHIT scores in UVH patients.

CONCLUSIONS

PS analysis demonstrated to be useful in differentiating CGD and UVH patients each other and when compared to CON, to objectively represent perceived symptoms filled along the DHI scale and to corroborate the rate of vestibular deficit in UVH patients.

Does Cognitive Dysfunction Correlate With Dizziness Severity in Meniére's Disease Patients

OBJECTIVE

Characterize the relationship between cognitive dysfunction and the dizziness severity in Meniére's disease (MD) patients.

STUDY DESIGN

Retrospective review.

SETTING

University-based tertiary medical center.

PATIENTS

Three hundred patients were evaluated for MD from 2015 to 2019. Excluding comorbid or alternative vestibular disorders, 29 patients with definite MD and available pre- and postintervention data were included for analysis.

INTERVENTIONS

A progressive protocol of salt restriction, diuretics, steroid and/or gentamycin injection, and endolymphatic sac decompression for those refractory to medical therapy.

MAIN OUTCOME MEASURES

Quality of life measured with the Dizziness Handicap Inventory (DHI) and cognitive function measured with the Cognitive Failures Questionnaire (CFQ). Pre- and posttreatment DHI and DHI subscale scores and change in these scores were correlated with pre- and posttreatment CFQ scores and change in CFQ with therapy.

RESULTS

Analysis showed a number of limited associations between improvement in DHI and improvement in CFQ. Total DHI scores failed to correlate scores or variation in scores with change in CFQ (p = 0.091 and p = 0.085, respectively). Improvement in the CFQ false-triggering domain was significantly associated with improvement in the DHI physical subscale (r = 0.491, p = 0.007) and was nonsignificantly associated with improvement in total DHI and DHI emotional subscale scores (r = 0.422, p = 0.016 and r = 0.399, p = 0.032).

CONCLUSIONS

The DHI correlates with several pre- and posttreatment measures of cognitive dysfunction (CFQ) in MD patients. However, change in DHI and CFQ with therapy correlate poorly. Overall, the commonly used DHI may fail to adequately assess cognitive dysfunction in MD patients possibly due to factors not directly implicated by measures of vestibular dysfunction, such as central nervous system or cognitive dysfunction; however, the specific physical and emotional subscales may offer helpful insight into cognitive dysfunction change/improvement with treatment.

Vestibular Functioning in Children with Neurodevelopmental Disorders Using the Functional Head Impulse Test

Several studies in children with neurodevelopmental disorders (NDDs) including autism spectrum disorders (ASDs), reading impairment, or attention deficit/hyperactive disorder (ADHD) pointed toward a potential dysfunction of the vestibular system, specifically in its complex relationship with the cerebellum. The aim of the present study was to test the functional vestibulo-ocular reflex (VOR) responses in children with NDDs to measure functional performance of the vestibular system. The VOR is specifically involved in this stabilization of the image on the retina during rapid movements of the head. To perform this study, four groups of children with ASD, ADHD, reading impairment, and with neurotypical development (TD) were enrolled (n = 80). We performed the functional head impulse test (fHIT), which measured the percentage of correct responses by asking the child to identify an optotype briefly presented during passive head impulse in each direction of each semicircular canal plane. We observed significantly lower correct answers in children with NDDs compared with those with TD (p < 0.0001). Surprisingly, there was no significant difference between the three groups of children with NDDs. Our study fostered preliminary evidence suggesting altered efficiency of vestibular system in children with NDDs. VOR abnormalities estimated using the fHIT could be used as a proxy of NDD impairments in children, and represent a potential biomarker.

Altered Regional Cerebral Blood Perfusion in Mild Cognitive Impairment Patients with Dizziness

Dizziness is a common symptom among the general population, especially in the elderly. Previous studies have reported that dizziness may be associated with various cognitive functions including memory impairment. However, few studies have investigated the neural correlates of dizziness in patients with cognitive impairment. The aim of this study was to examine regional cerebral blood flow (rCBF) in mild cognitive impairment (MCI) patients with or without dizziness using single photon emission computed tomography (SPECT). A total of 50 patients with MCI were recruited. All participants underwent technetium-99m ethyl cysteinate dimer brain SPECT and a neuropsychological battery and completed the Dizziness Handicap Inventory (DHI). Participants were divided into a dizziness group (DHI ≥ 1, n = 18) and a non-dizziness group (DHI = 0, n = 32). Voxel wise differences in rCBF between the groups were estimated. SPECT analysis revealed decreased rCBF in the left superior temporal gyrus, left lateral orbital gyrus, and right middle frontal gyrus in the dizziness group compared with the non-dizziness group (p < 0.005). No significant clusters of increased rCBF were observed in the dizziness group compared with the non-dizziness group. Results of the neuropsychological tests showed a significant difference in Controlled Oral Word Association Test performance between MCI patients with and without dizziness. In conclusion, MCI patients with dizziness showed multifocal frontal and left temporal hypoperfusion compared with patients without dizziness. Our results suggest that hypoperfusion in the frontal and temporal cortices might be reflecting the negative impact of dizziness in MCI patients.

[Poststroke cognitive impairment and the possibility of its nonpharmacological treatment with vestibular stimulation based on biological feedback to supporting reaction]

Cognitive impairment is common in poststroke patients. Today in rehabilitation programs the specialists use the vestibular stimulation including biological feedback to supporting reaction for treatment poststroke cognitive impairment. These studies show the relationship of vestibular function with memory, attention, spatial orientation, navigation, mental representation of three-dimensional space and other cognitive functions. It makes possible to build rehabilitation programs for patients with stroke.