Gait and Falls in Benign Paroxysmal Positional Vertigo: A Systematic Review and Meta-analysis.

BACKGROUND AND PURPOSE: Benign paroxysmal positional vertigo (BPPV) is one of the most common vestibular disorders, and is treated effectively with particle repositioning maneuvers (PRM). The aim of this study was to assess the influence of BPPV and treatment effects of PRM on gait, falls, and fear of falling. METHODS: Three databases and the reference lists of included articles were systematically searched for studies comparing gait and/or falls between (1) people with BPPV (pwBPPV) and controls and (2) pre- and posttreatment with PRM. The Joanna Briggs Institute critical appraisal tools were used to assess risk of bias. RESULTS: Twenty of the 25 included studies were suitable for meta-analysis. Quality assessment resulted in 2 studies with high risk of bias, 13 with moderate risk, and 10 with low risk. PwBPPV walked slower and demonstrated more sway during tandem walking compared with controls. PwBPPV also walked slower during head rotations. After PRM, gait velocity during level walking increased significantly, and gait became safer according to gait assessment scales. Impairments during tandem walking and walking with head rotations did not improve. The number of fallers was significantly higher for pwBPPV than for controls. After treatment, the number of falls, number of pwBPPV who fell, and fear of falling decreased. DISCUSSION AND CONCLUSIONS: BPPV increases the odds of falls and negatively impacts spatiotemporal parameters of gait. PRM improves falls, fear of falling, and gait during level walking. Additional rehabilitation might be necessary to improve gait while walking with head movements or tandem walking.Video Abstract available for more insights from the authors (see the Supplemental Digital Content Video, available at: http://links.lww.com/JNPT/A421 ).

Circulating Follicular Regulatory T Cells Are Defective in Multiple Sclerosis.

Follicular regulatory T cells (TFR) have been extensively characterized in mice and participate in germinal center responses by regulating the maturation of B cells and production of (auto)antibodies. We report that circulating TFR are phenotypically distinct from tonsil-derived TFR in humans. They have a lower expression of follicular markers, and display a memory phenotype and lack of high expression of B cell lymphoma 6 and ICOS. However, the suppressive function, expression of regulatory markers, and FOXP3 methylation status of blood TFR is comparable with tonsil-derived TFR. Moreover, we show that circulating TFR frequencies increase after influenza vaccination and correlate with anti-flu Ab responses, indicating a fully functional population. Multiple sclerosis (MS) was used as a model for autoimmune disease to investigate alterations in circulating TFR. MS patients had a significantly lower frequency of circulating TFR compared with healthy control subjects. Furthermore, the circulating TFR compartment of MS patients displayed an increased proportion of Th17-like TFR. Finally, TFR of MS patients had a strongly reduced suppressive function compared with healthy control subjects. We conclude that circulating TFR are a circulating memory population derived from lymphoid resident TFR, making them a valid alternative to investigate alterations in germinal center responses in the context of autoimmune diseases, and TFR impairment is prominent in MS.

Three Years of Vestibular Infant Screening in Infants With Sensorineural Hearing Loss.

OBJECTIVES: Although vestibular deficits are more prevalent in hearing-impaired children and can affect their development on many levels, a pediatric vestibular assessment is still uncommon in clinical practice. Since early detection may allow for timely intervention, this pioneer project has implemented a basic vestibular screening test for each six-month-old hearing-impaired infant in Flanders, Belgium. This study aims to report the vestibular screening results over a period of three years and to define the most important risk factors for abnormal vestibular screening results. METHODS: Cervical Vestibular Evoked Myogenic Potentials with bone-conduction were used as a vestibular screening tool in all reference centers affiliated to the Universal Newborn Hearing Screening Program in Flanders. From June 2018 until June 2021, 254 infants (mean age: 7.4 months, standard deviation: 2.4 months) with sensorineural hearing loss were included. RESULTS: Overall, abnormal vestibular screening results were found in 13.8% (35 of 254) of the infants. The most important group at risk for abnormal vestibular screening results were infants with unilateral or bilateral severe to profound sensorineural hearing loss (20.8%, 32 of 154) (P < .001, odds ratio = 9.16). Moreover, abnormal vestibular screening results were more prevalent in infants with hearing loss caused by meningitis (66.7%, 2 of 3), syndromes (28.6%, 8 of 28), congenital cytomegalovirus infection (20.0%, 8 of 40), and cochleovestibular anomalies (19.2%, 5 of 26). CONCLUSIONS: The vestibular screening results in infants with sensorineural hearing loss indicate the highest risk for vestibular deficits in severe to profound hearing loss, and certain underlying etiologies of hearing loss, such as meningitis, syndromes, congenital cytomegalovirus, and cochleovestibular anomalies.

Vestibular Infant Screening (VIS)-Flanders: results after 1.5 years of vestibular screening in hearing-impaired children.

Due to the close anatomical relationship between the auditory and vestibular end organs, hearing-impaired children have a higher risk for vestibular dysfunction, which can affect their (motor) development. Unfortunately, vestibular dysfunction often goes unnoticed, as vestibular assessment in these children is not standard of care nowadays. To timely detect vestibular dysfunction, the Vestibular Infant Screening-Flanders (VIS-Flanders) project has implemented a basic vestibular screening test for hearing-impaired infants in Flanders (Belgium) with a participation rate of 86.7% during the first year and a half. The cervical Vestibular Evoked Myogenic Potentials (cVEMP) test was applied as vestibular screening tool to map the occurrence of vestibular (mainly saccular) dysfunction in this population. At the age of 6 months, 184 infants were screened. No refers on vestibular screening were observed in infants with permanent conductive hearing loss. In infants with permanent sensorineural hearing loss, a cVEMP refer rate of 9.5% was observed. Failure was significantly more common in infants with severe-profound compared to those with mild-moderate sensorineural hearing loss (risk ratio = 9.8). Since this is the first regional study with a large sample size and successful participation rate, the VIS-Flanders project aims to set an example for other regions worldwide.

Occupational noise, smoking, and a high body mass index are risk factors for age-related hearing impairment and moderate alcohol consumption is protective: a European population-based multicenter study.

A multicenter study was set up to elucidate the environmental and medical risk factors contributing to age-related hearing impairment (ARHI). Nine subsamples, collected by nine audiological centers across Europe, added up to a total of 4,083 subjects between 53 and 67 years. Audiometric data (pure-tone average [PTA]) were collected and the participants filled out a questionnaire on environmental risk factors and medical history. People with a history of disease that could affect hearing were excluded. PTAs were adjusted for age and sex and tested for association with exposure to risk factors. Noise exposure was associated with a significant loss of hearing at high sound frequencies (>1 kHz). Smoking significantly increased high-frequency hearing loss, and the effect was dose-dependent. The effect of smoking remained significant when accounting for cardiovascular disease events. Taller people had better hearing on average with a more pronounced effect at low sound frequencies (<2 kHz). A high body mass index (BMI) correlated with hearing loss across the frequency range tested. Moderate alcohol consumption was inversely correlated with hearing loss. Significant associations were found in the high as well as in the low frequencies. The results suggest that a healthy lifestyle can protect against age-related hearing impairment.

Age-related hearing impairment (ARHI): environmental risk factors and genetic prospects.

This paper reviews what is known about the environmental risk factors and medical conditions that contribute to age-related hearing impairment (ARHI), and evaluates which analyses could be performed to identify genetic factors that are involved. Although hearing acuity declines with aging in everybody, the variation in hearing thresholds is large. Part of this variation can be explained by medical conditions, and by a different exposure to environmental factors. In particular, many studies have been dedicated to the influence of occupational noise on hearing. The importance of other environmental risk factors is less clear and often controversial. In contrast, almost nothing is known about the genetic compound of ARHI. Heritability estimates have shown that approximately half of the variance in ARHI is due to heritable factors, which indicates that ARHI is a complex trait, influenced by an interplay between genetics and environment. Although several genes for monogenic hearing impairment have been identified in mouse and man, no susceptibility genes for ARHI have been identified yet. The methodology to dissect the genetics of complex traits is still developing. Possible study designs to unravel the genetics of ARHI are discussed.

A novel Z-score-based method to analyze candidate genes for age-related hearing impairment.

OBJECTIVE: Approximately half of the variance of Age-Related Hearing Impairment (ARHI) is attributable to environmental risk factors, and the other half to genetic factors. None of these genes has ever been identified, but the genes involved in monogenic nonsyndromic hearing impairment are good candidates. Here we define and validate a quantitative trait value for ARHI, correcting for age and gender, to allow the genetic study of ARHI as a quantitative trait. DESIGN: Based on the ISO 7029 standard, we convert audiometric data into a Z-score, an age- and gender-independent value expressing to what extent a person is affected by ARHI. The validity of this approach is checked using a test population of randomly collected subjects. The power to evaluate the contribution of a candidate gene to ARHI is assessed using simulated populations. As an example, one ARHI candidate gene is analyzed. RESULTS: In our test population, Z-scores were normally distributed although the mean did not equal zero. Z-scores were independent of age, and there was no difference between men and women. Power studies using simulated populations indicated that to detect moderate genetic effects, sample sizes of at least 500 random subjects are necessary. CONCLUSION: The Z-score conversion appears to be a valid method to describe to what extent a subject is affected by ARHI, allowing to compare persons from different age and gender. This method can be the basis of future, powerful studies to identify ARHI genes.