The Price of Immune Responses and the Role of Vitamin D in the Inner Ear

The Relationship Between Lower Vitamin D Levels and Hearing Loss in Older Adults

BACKGROUND AND OBJECTIVES

Age-related hearing loss (ARHL) is a sensorineural disease that is associated with a number of factors. In addition to age, sex, environment, lifestyle, and comorbidities are all known to be related to ARHL as well. The prevalence of ARHL can be reduced by controlling the adjustable factors that cause it. Vitamin D levels are strongly related to calcium metabolism, which can affect ARHL. This study aimed to investigate the association between vitamin D and ARHL.

SUBJECTS AND METHODS

A total of 1,104 subjects aged >65 years were enrolled from the fifth Korean National Health and Nutrition Examination Survey, which was conducted from 2010-2012. Every participant received both an audiological assessment and a nutritional survey. The association between ARHL and serum vitamin D concentration was analyzed using logistic regression analyses with complex sampling adjusted for confounding factors such as alcohol consumption, smoking status, mobility, and bone mineral density.

RESULTS

Our multivariable analysis revealed that males in the group with lower serum levels of vitamin D (< 20 ng/mL) had a higher prevalence of ARHL (odds ratio, 1.638, 95% confidence interval, 1.058-2.538, p=0.027).

CONCLUSIONS

This finding suggests that lower serum levels of vitamin D are associated with ARHL in the older male population.

Understanding Factors That Cause Benign Paroxysmal Positional Vertigo, Ménière Disease, and Vestibular Neuritis: A Two-Sample Mendelian Randomization Study

OBJECTIVES

Vertigo is a prevalent clinical symptom, frequently associated with benign paroxysmal positional vertigo (BPPV), Ménière disease (MD), and vestibular neuritis (VN), which are three common peripheral vestibular disorders. However, there is a relative lack of research in epidemiology and etiology, with some existing studies presenting discrepancies in their conclusions. We conducted a two-sample Mendelian randomization (MR) analysis to explore potential risk and protective factors for these three peripheral vestibular disorders.

DESIGN

Based on genome-wide association studies, we executed a univariable MR to investigate the potential associations between 38 phenotypes and MD, BPPV, and VN. We used the inverse variance weighted method as the primary MR result and conducted multiple sensitivity analyses. We used false discovery rate (FDR) correction to control for type I errors. For findings that were significant in the univariable MR, a multivariable MR analysis was implemented to ascertain direct effects. In addition, we replicated analyses of significant results from the univariable MR to enhance the robustness of our analyses.

RESULTS

For BPPV, both alcohol consumption (odds ratio [OR] = 0.57, 95% confidence interval [CI] = 0.43 to 0.76, FDR Q = 0.004) and educational attainment (OR = 0.77, 95% CI = 0.68 to 0.88, FDR Q = 0.003) were found to decrease the risk. The genetic prediction analysis identified major depression (OR = 1.75, 95% CI = 1.28 to 2.39, FDR Q = 0.008) and anxiety (OR = 5.25, 95% CI = 1.79 to 15.42, FDR Q = 0.036) increased the risk of MD. However, the impact of major depression on MD could be influenced by potential horizontal pleiotropy. Systolic blood pressures (OR = 1.03, 95% CI = 1.02 to 1.04, FDR Q = 4.00 × 10 -7 ) and diastolic blood pressures (OR = 1.05, 95% CI = 1.03 to 1.07, FDR Q = 2.83 × 10 -6 ) were associated with an increased risk of VN, whereas high-density lipoprotein (OR = 0.77, 95% CI = 0.67 to 0.89, FDR Q = 0.009) and urate (OR = 0.75, 95% CI = 0.63 to 0.91, FDR Q = 0.041) reduces the risk of VN. Only the relationship between urate and VN was not replicated in the replication analysis. Multivariable MR showed that the protective effect of education on BPPV was independent of Townsend deprivation index. The protective effect of high-density lipoprotein against VN was independent of triglycerides and apolipoprotein A1. The risk impacts of systolic and diastolic blood pressures on VN exhibited collinearity, but both are independent of chronic kidney disease and estimated glomerular filtration rate. The impacts of anxiety and severe depression on MD demonstrated collinearity.

CONCLUSIONS

Our study identified the risk association between systolic and diastolic blood pressure with VN and the protective influence of high-density lipoprotein on VN, which may support the vascular hypothesis underlying VN. Furthermore, we observed an elevated risk of MD associated with anxiety. The potential protective effects of education and alcohol consumption on BPPV need further exploration in subsequent studies to elucidate specific mechanistic pathways. In summary, our MR study offers novel insights into the etiology of three peripheral vestibular diseases from a genetic epidemiological standpoint.

Vestibular function is associated with immune inflammatory response

Association between vestibular function and immune inflammatory response has garnered increasing interest. Immune responses can lead to anatomical or functional alterations of the vestibular system, and inflammatory reactions may impair hearing and balance. Vestibular disorders comprise a variety of conditions, such as vestibular neuritis, benign paroxysmal positional vertigo, Meniere's disease, vestibular migraine, posterior circulation ischemia, and bilateral vestibular disease. Moreover, some patients with autoimmune diseases develop vestibulocochlear symptom. This paper offers an overview of prevalent vestibular diseases and discusses associations between vestibular dysfunction and immune diseases.

Association between vitamin D deficiency and benign paroxysmal positional vertigo (BPPV) incidence and recurrence: a systematic review and meta-analysis

OBJECTIVES

The objective of this study is to determine the relationship between serum vitamin D level and the risk of developing benign paroxysmal positional vertigo (BPPV) incidence and recurrence in countries in the Northern Hemisphere.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Scopus and Web of Science databases were searched for studies published between January 2000 and February 2023.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Participants located in the Northern Hemisphere aged 18 or over with at least one episode of BPPV, serum 25-hydroxyvitamin D levels measured and reported, no comorbidities or history of vitamin D supplementation.

DATA EXTRACTION AND SYNTHESIS

Data extraction and synthesis were performed by a single reviewer and checked by a second reviewer. Inclusion and exclusion criteria and risk of bias were assessed by two independent reviewers using the Newcastle Ottawa Tool for Cohort studies and Risk of Bias Assessment Tool for Nonrandomised Studies checklist for case-control studies. Meta-analysis was conducted using random effects models. Standard mean difference with a 95% CI was used to measure the relationship between vitamin D level and BPPV.

RESULTS

The 35 articles identified by the literature search reported data of 9843 individuals. 19 studies (7387 individuals) were included in the BPPV incidence meta-analysis while 7 studies (622 individuals) were included in the BPPV recurrence meta-analysis. Lower serum vitamin D levels were found in BPPV incidence compared with controls, but the relationship between vitamin D levels in recurrent BPPV compared with non-recurrent disease remained uncertain.

CONCLUSION

Results of this systematic review and meta-analysis demonstrated a negative correlation between serum vitamin D and BPPV incidence, while any relationship between serum vitamin D and BPPV recurrence remained uncertain. Risk of bias analysis revealed evidence of variable quality. There were insufficient data available to evaluate seasonal relationships between serum vitamin D and BPPV. Given the potential for this as a confounding factor, future research should aim to investigate this further.

PROSPERO REGISTRATION NUMBER

CRD42021271840.

Vitamin D Supplementation and Recurrence of Benign Paroxysmal Positional Vertigo

Positional vertigo manifests as a spinning sensation triggered by changes in head position relative to gravity. Benign paroxysmal positional vertigo (BPPV) is an inner ear disorder characterized by recurrent episodes of positional vertigo. The connection between vitamin D insufficiency/deficiency and the onset and recurrence of BPPV is established. This study aims to assess vitamin D as a recurring factor in BPPV and the efficacy of vitamin D supplementation in preventing its recurrence. A comprehensive literature review on the relationship between vitamin D and BPPV recurrence was conducted, searching PubMed, Embase, Web of Science, and article reference lists for studies published from 2020 to 2023. A total of 79 articles were initially identified through the search, with 12 of them being utilized in the study. Recurrence rates for BPPV varied from 13.7% to 23% for studies with follow-up less than 1 year and 13.3% to 65% for studies with follow-up equal to or exceeding 2 years. Risk factors for BPPV recurrence include advanced age, female sex, hypertension, diabetes mellitus, hyperlipidemia, osteoporosis, and vitamin D deficiency. While earlier studies did not establish a link between low vitamin D levels and initial BPPV occurrence, they did associate recurrent episodes with low vitamin D levels. Recent research indicates that vitamin D supplementation in BPPV patients with deficiency or insufficiency decreases both the numbers of relapsing patients and relapses per patient. To validate these findings across diverse populations, further randomized controlled studies with larger cohorts and extended follow-up durations are essential.

Bile Acid Application in Cell-Targeting for Molecular Receptors in Relation to Hearing: A Comprehensive Review

Bile acids play important roles in the human body, and changes in their pool can be used as markers for various liver pathologies. In addition to their functional effects in modulating inflammatory responses and cellular survivability, the unconjugated or conjugated, secondary, or primary nature of bile acids accounts for their various ligand effects. The common hydrophilic bile acids have been used successfully as local treatment to resolve drug-induced cell damage or to ameliorate hearing loss. From various literature references, bile acids show concentration and tissue-dependent effects. Some hydrophobic bile acids act as ligands modulating vitamin D receptors, muscarinic receptors, and calcium-activated potassium channels, important proteins in the inner ear system. Currently, there are limited resources investigating the therapeutic effects of bile acid on hearing loss and little to no information on detecting bile acids in the remote ear system, let alone baseline bile acid levels and their prevalence in healthy and disease conditions. This review presents both hydrophilic and hydrophobic human bile acids and their tissue-specific effects in modulating cellular integrity, thus considering the possible effects and extended therapeutic applicability of bile acids to the inner ear tissue.

Effects of vestibular rehabilitation training combined with anti-vertigo drugs on vertigo and balance function in patients with vestibular neuronitis: a systematic review and meta-analysis

Objective

To investigate the effects of vestibular rehabilitation training (VRT) combined with anti-vertigo drugs on vertigo and balance function in patients with vestibular neuronitis (VN).

Data sources

PubMed, EMBASE, The Cochrane Library, Web of Science, CNKI, Wan Fang Data, VIP, and CBM were searched until July 13, 2023.

Participants

Patients with vestibular neuronitis participated in the study.

Results

Twenty one studies including 1,415 patients were included in this review for meta-analysis. According to the Physiotherapy Evidence Database (PEDro) quality assessment, four studies received high quality (≥seven scores) and 17 studies received moderate quality (six scores). The meta-analysis showed that VRT combined with anti-vertigo drugs significantly reduced the Dizziness Handicap Inventory (DHI) score, the Vestibular Disorders Activities of Daily Living Scale (VADL) score and the Canal Paresis (CP) score, and improved the overall efficiency and the Berg Balance Scale (BBS) score, promoting vestibular evoked myogenic potentials (VEMPs) returned to normal in VN compared to simple anti-vertigo drugs or VRT alone.

Conclusion

The results of this meta-analysis demonstrate the efficacy and safety of VRT combined with anti-vertigo drugs in patients with VN. Combined therapy can alleviate vestibular dysfunction such as vertigo and vomiting in patients, improve daily activity ability and balance ability, in addition to VRT has fewer adverse reactions, so it is extremely safe. However, there are shortcomings such as lack of long-term follow-up and different frequency and duration of treatment. Therefore, future randomized controlled trials (RCTs) with larger sample sizes and longer-term observations are needed to verify the effectiveness of VRT in combination with anti-vertigo drugs for VN.Systematic Review Registration: https://www.crd.york.ac.uk/prospero/.

In silico pharmacological study of AQP2 inhibition by steroids contextualized to Ménière's disease treatments

Ménière's disease (MD) is characterized by an abnormal dilatation of the endolymphatic compartment called endolymphatic hydrops and is associated with fluctuating hearing losses and vertigo. Corticosteroid treatment is typically administered for its anti-inflammatory effects to MD patients. However, we recently described for the first time a direct interaction of two corticosteroids (dexamethasone and cortisol) with human AQP2 which strongly inhibited water fluxes. From these initial studies, we proposed an AQPs Corticosteroids Binding Site (ACBS). In the present work, we tested the interaction of 10 molecules associated to the steroid family for this putative ACBS. We observed a wide diversity of affinity and inhibitory potential of these molecules toward AQP2 and discussed the implications for inner ear physiology. Among the tested compounds, cholecalciferol, calcitriol and oestradiol were the most efficient AQP2 water permeability inhibitors.

Role of Serum Markers in Benign Paroxysmal Positional Vertigo: Are They Useful?

Benign Paroxysmal Positional Vertigo is a peripheral labyrinthine disease and is one of the most common causes of dizziness in the general population. The proposed study was conducted in the Department of Otorhinolaryngology - Head and Neck Surgery at Indira Gandhi Medical College and Hospital, Shimla, Himachal Pradesh for a period of one year. About 44 patients aged between 14 and 60 years who came out positive on Dix Hallpike test and were willing for study were included in case group, whereas 44 patients aged 14-60 years who came out negative on Dix Hallpike test and with no complaint of vertiginous feeling were included in control group. Cases and controls were subjected to blood investigations like complete hemogram, calcium, vitamin D and uric acid. The mean Vitamin D was found to be significantly less in Case group (27.90 ± 15.89) compared to the Control group (39.05 ± 21.15) while no significant difference in mean Serum Calcium was observed between the Case group (8.48 ± 1.28) and Control group (8.88 ± 1.25). Serum uric acid levels were also compared and no significant difference was found between Case group (4.12 ± 1.15) and the Control group (4.06 ± 0.95). Our study found that there is relation between low vitamin D levels and occurrence of BPPV. Which supports the hypothesis that supplementation of Vitamin D might be helpful in preventing the occurrence and more frequent recurrence of BPPV. However in our study no association was found between serum calcium and uric acid levels with BPPV.

Differential Volume Increase of Endolymphatic Compartments in Ménière's Disease Is Inversely Associated With Membrane Thickness

OBJECTIVES

Our aim in this study was to characterize the morphology of the endolymphatic compartment on histopathology in individuals with Ménière's disease (MD) and to determine why hydrops of the saccule is more pronounced than that of other compartments of the inner ear in MD.

METHODS

Temporal bones from 9 patients with idiopathic MD and from 10 individuals without MD/endolymphatic hydrops were examined. The inner ear fluid compartments in normal ears, and ears with MD were three-dimensionally reconstructed and their volume was calculated. The thickness of the membranes of the labyrinth was measured, and both ruptures of the membranes and patency of the utriculoendolymphatic (UEV; Bast's) valve were assessed.

RESULTS

In ears with MD, the saccule and the cochlear duct were most frequently hydropic; the utricle was involved approximately half as frequently. In ears without MD, the Reissner's membrane and the membranous wall of the saccule were thinner than that of the utricle and of the lateral semicircular canal ( p < 0.01). The lateral semicircular canal did not show signs of hydrops. In all ears with MD in which the utricle exceeded the average volume of normals (6 of 12), the UEV was open or there was a rupture in the utricle.

CONCLUSION

Increases in endolymphatic pressure may cause a primary swelling of the apical cochlear duct and saccule, both of which have relatively thin membranes. Hydrops in the utricle may occur less frequently because of a thicker wall, because of a functioning UEV, and when the saccule has already occupied most of the vestibular perilymphatic space.

[Serum 25-hydroxyvitamin D expression and its correlation in patients with vestibular neuritis]

Objective:To investigate the expression level of serum 25-（OH） D and its correlation in patients with vestibular neuritis（VN）. Methods:30 acute VN patients and 50 age-and sex-matched healthy controls who attended the Otolaryngology, Head and Neck Surgery Department of the First Hospital of Shanxi Medical University from October 2020 to October 2021 were selected. The demographic and clinical data of all subjects were recorded, the levels of serum 25-（OH） D and inflammatory markers were measured and compared, and the changes of serum 25-（OH） D levels in convalescent patients with VN were followed up. Results:The serum level of 25-（OH） D in the acute phase VN group was significantly lower than that in healthy controls[（10.14±2.92） ng/mL vs （20.61±4.70） ng/mL, P<0.01], and the deficiency rate of 100.0%（30/30） was significantly higher than 54.0%（27/50）. Moreover, the serum level of 25-（OH） D in the recovery period（3 months later） was significantly higher[（10.14±2.92） ng/mL vs （15.94±4.88） ng/mL, P<0.01], and the deficiency rate was significantly decreased by 76.7%（23/30）. However, the serum 25-（OH） D level was significantly lower in both the VN group than that in both the acute period and the recovery group, and the deficiency rate was significantly higher than that in the control group. Multivariate binary Logistic regression model analysis showed that low-level serum 25-（OH） D was associated with the onset of VN, with an OR value of 0.193（95%CI=0.043-0.861, P=0.031）. In addition, the results of this study showed that peripheral blood leukocyte（WBC） and neutrophil / lymphocyte ratio（NLR） levels in the acute VN group were significantly higher than in healthy controls[（7.65±3.02） ×10⁸/L vs （5.50±2.50） ×10⁸/L, P<0.01; （2.46±2.95） ×100% vs（1.67±0.92） ×100%, P<0.01 ], and there was no significant difference in Platelet / lymphocyte ratio（PLR） and and average platelet volume（MPV） levels in the two groups（P>0.05）. There were no significant differences in age distribution, sex ratio, body mass index, persistent health problems, or lifestyle groups（P>0.05）. Conclusion:This study is the first to detect serum 25-（OH） D level and inflammation index level, and dynamically assess the serum 25-（OH） D level in different stages, found that low serum 25-（OH） D is associated with the onset of VN, physiological concentration of serum 25-（OH） D is a protective factor of VN, vitamin D supplementation therapy may be a new target of VN treatment.

Low 25-Hydroxyvitamin D Levels Are Associated With Residual Dizziness After Successful Treatment of Benign Paroxysmal Positional Vertigo

Objective:

Vitamin D (Vit D) regulates calcium and phosphate metabolism and helps to maintain otolith organ function. Residual dizziness (RD) is one of the most common complications after the successful treatment of benign paroxysmal positional vertigo (BPPV). Various theories have been suggested to explain the cause of RD, and otolith organ disorder is the most evident cause of RD. This study aimed to investigate the association between serum levels of Vit D and the occurrence of RD after the successful treatment of BPPV.

Methods

A prospective study including patients who were diagnosed with de novo posterior semicircular canal-type BPPV (PC-BPPV) was conducted at our institution from May 2017 to May 2019. All the patients underwent canalith repositioning procedures and were followed up. Univariate and multivariate analyses were performed to investigate the relationship between serum 25-hydroxy vitamin D (25(OH)D) levels and RD occurrence after successful BPPV treatment.

Results

In total, 123 patients with PC-BPPV were enrolled, and 41.5% (51/123) experienced RD. The serum level of 25(OH)D was significantly lower in PC-BPPV patients with RD [median 16.2 ng/ml (IQR 12.9–22.1)] than in patients without RD [median 20.5 ng/ml (IQR 16.5–26.5)] (P = 0.001). In multivariate models comparing the prevalence of RD in the insufficient group [25(OH)D ≥ 20 to <30 ng/ml], deficient group [25(OH)D < 20 ng/ml] and normal group [25(OH)D ≥ 30 ng/ml], the 25(OH)D levels in the deficient group were associated with the occurrence of RD (odds ratio = 5.48, 95% confidence interval = 1.08–27.71; P = 0.04).

Conclusion

Low 25(OH)D levels are associated with the development of RD in patients with PC-BPPV after successful treatment. Further efforts to validate and elucidate the mechanism are needed.

Vitamin D deficiency in benign paroxysmal positional vertigo

Aim. To assess the level of vitamin D (D3) in patients with benign paroxysmal positional vertigo (BPPV). Materials and methods. The study included 25 patients. The control group consisted of 30 people, comparable in age with the main group, without BPPV. All patients included in the study underwent a standard examination of the vestibular sphere, which compised the Head impulse test, the Fukuda test, the Shaking test, the DixHolpike and MacluraPagnini test. Hydroxyvitamin D levels were analyzed by enzyme immunoassay. In the study of the psychological sphere, the following questionnaires were used: Dizziness Handicap Inventory, Beck Depression Scale, SpielbergerKhanin Anxiety Scale, TAS-26 alexithymia scale. Results. The average level of hydroxyvitamin D among patients was 19.658.6 ng/ml, which corresponds to a deficiency of vitamin D, in the control group, vitamin D3 was within the reference values (30100 ng/ml) and amounted to 33.7810.7 ng/ml (p0.001). There is a negative correlation between the level of hydroxyvitamin D and the age of the patients. There is a correlation (Spearman's criterion -0.463254, p0.001) between the frequency of recurrence of BPPV and a decrease in the level of hydroxyvitamin D. Conclusion. Vitamin D deficiency prevails among patients with BPPV.

The role of vitamin D in subjective tinnitus-A case-control study

Regarding the high prevalence of vitamin D (25(OH)D) deficiency in the population and its possible association with ear diseases, we aimed to investigate the 25(OH)Dserum level in patients with subjective, nonpulsating tinnitus and its effect on tinnitus severity. The study included 201 tinnitus patients and 99 controls. Patient clinical information, including tinnitus characteristics and severity according to Tinnitus Handicap Inventory (THI), loudness assessed by Visual Analogue Scale (VAS), audiometry, and the blood level of vitamin D, was recorded. The level of 25(OH)D in tinnitus patients was significantly decreased compared with the controls (19.86 ± 7.53 and 27.43 ± 8.85 ng/ml, respectively; P value < 0.0001). More patients in the tinnitus group were deficient in vitamin D, compared with the controls (50.7% vs. 22.2% respectively, p < 0.0001). Tinnitus patients with a lower serum level of 25(OH)D (≤15 ng/dl) were significantly younger, had a higher degree of tinnitus severity measured with THI and VAS scales, had higher triglyceride and TSH levels, and a lower HDL level compared with individuals who had higher 25(OH)D level (>15 ng/dl). There was a strong correlation between the 25(OH)D level and THI. Our findings suggest that a large proportion of tinnitus patients suffers from vitamin D deficiency and that the vitamin D level correlates with tinnitus impact. We recommend a vitamin D assessment for all tinnitus patients.

A Review on Recent Advancement on Age-Related Hearing Loss: The Applications of Nanotechnology, Drug Pharmacology, and Biotechnology

Aging is considered a contributing factor to many diseases such as cardiovascular disease, Alzheimer’s disease, and hearing loss. Age-related hearing loss, also termed presbycusis, is one of the most common sensory impairments worldwide, affecting one in five people over 50 years of age, and this prevalence is growing annually. Associations have emerged between presbycusis and detrimental health outcomes, including social isolation and mental health. It remains largely untreatable apart from hearing aids, and with no globally established prevention strategies in the clinical setting. Hence, this review aims to explore the pathophysiology of presbycusis and potential therapies, based on a recent advancement in bile acid-based bio-nanotechnologies. A comprehensive online search was carried out using the following keywords: presbycusis, drugs, hearing loss, bile acids, nanotechnology, and more than 150 publications were considered directly relevant. Evidence of the multifaceted oxidative stress and chronic inflammation involvement in cellular damage and apoptosis that is associated with a loss of hair cells, damaged and inflamed stria vascularis, and neuronal signalling loss and apoptosis continues to emerge. New robust and effective therapies require drug delivery deeper into the various layers of the cochlea. Bile acid-based nanotechnology has gained wide interest in its permeation-enhancing ability and potential for numerous applications in treating presbycusis.

No evidence for a specific vitamin D deficit in benign paroxysmal positional vertigo

BACKGROUND AND PURPOSE

The aim was to investigate whether there is a difference in serum 25-hydroxyvitamin D (25(OH)D) concentration between patients with benign paroxysmal positional vertigo (BPPV), patients with other vestibular diseases and patients with other neurological non-vestibular diseases presenting in a tertiary neurological academic outpatient clinic.

METHODS

The serum 25(OH)D concentration was measured in 680 patients (368 male, mean age ± SD 58 ± 17 years, 661 Caucasian) without vitamin D supplementation. 158 patients had BPPV; 221 had other vestibular diseases (including 122 with peripheral vestibular disorders, such as unilateral vestibulopathy or Ménière's disease; 46 with central vestibular disorders, such as vestibular migraine or cerebellar dizziness; 53 with functional dizziness); and 301 patients with other neurological non-vestibular diseases.

RESULTS

There was no significant difference in the serum 25(OH)D concentration between patients with BPPV (mean ± SD 23.4 ± 9.4 ng/ml) and those with other vestibular disorders (24.9 ± 10.1 ng/ml, p = 0.324). Patients with other neurological disorders had even lower concentrations (21.4 ± 10.6 ng/ml) than patients with BPPV (p < 0.005), patients with other vestibular disorders (p < 0.005) and all patients with vestibular disorders (24.9 ± 10.1 ng/ml, p < 0.005).

CONCLUSION

Our analysis does not support the theory of a specific relationship between serum 25(OH)D concentration and the occurrence of BPPV or other vestibular disorders.

Effect of vitamin D supplementation on benign paroxysmal positional vertigo recurrence: A meta-analysis

Benign paroxysmal positional vertigo is characterized by recurrence, which exposes patients to repeated vertigo attacks. Vitamin D deficiency has been found to be a risk factor in benign paroxysmal positional vertigo, although effect of its elimination on recurrence reduction remains unknown. To determine the effect of vitamin D supplementation in preventing recurrence of benign paroxysmal positional vertigo patients with vitamin D deficiency using a meta-analysis study. We searched and retrieved relevant articles from several databases, then used the Cochrane evaluation system or Methodological Index for Non-Randomized Studies (MINORS) to assess the quality of studies. We adopted risk-ratio (RR) with corresponding 95% confidence interval (CI) to determine effect sizes, and further performed statistical analyses under a randomized- or fixed-effects model. Seven studies, comprising 602 and 731 participants in the case and control group respectively, met our inclusion criteria, and were therefore included in the meta-analysis. Assessment based on Cochrane evaluation system or MINORS revealed that most of the studies had high quality. Moreover, the randomized- model revealed that the vitamin D supplementation group had a lower recurrence rate than the control group which did not accepted vitamin D supplementation (RR = 0.41, 95% CI = 0.26-0.65, p < 0.01). Overall, these findings indicate that vitamin D supplementation can significantly lower recurrence in benign paroxysmal positional vertigo and vitamin D deficiency.

Association Between Serum Vitamin D Level and Ménière's Disease

OBJECTIVES

Ménière's disease (MD) is a well-known inner ear disease; however, the etiopathogenesis is unknown. Several factors may be involved. Meanwhile, vitamin D is reported to have an important role in inner ear physiology. The aim of this study is to evaluate the relation between vitamin D deficiency and MD.

STUDY DESIGN

This matched case-control study compared serum vitamin D levels between patients with definite MD and those without it.

SETTING

The study was done between August 2018 and December 2019 at Ghaem University Hospital in Mashhad, Iran.

METHODS

Twenty-eight patients with definite MD were matched with a group of 84 healthy individuals, regarding age, sex, body mass index, and occupation (indoor vs outdoor). The serum level of vitamin D (25-hydroxyvitamin D3) was measured in both groups.

RESULTS

The mean ± SD vitamin D level was 18.9 ± 9.7 ng/mL in the case group and 25.2 ± 13.7 ng/mL in the control group (P = .027). There was a significant difference between the case and control groups according to the results of the conditional logistic regression model (P = .03; adjusted odds ratio, 0.96). In the MD group, 17 (60.7%) patients were vitamin D deficient, 6 (21.4%) insufficient, and only 5 (17.9%) sufficient.

CONCLUSIONS

The results of this study show that serum vitamin D level in MD is significantly lower than that of the control group. However, the role of vitamin D supplementation in the management of MD needs further study.

LEVEL OF EVIDENCE

4.

Sensorineural Hearing Loss and Wernicke Encephalopathy: A Case Report and Literature Review

Sensorineural hearing loss (SNHL) is seldom associated with Wernicke encephalopathy (WE) or thiamine deficiency. While thiamine deficiency and repletion are often considered prior to dextrose infusions in patients with chronic alcohol abuse to prevent WE, they are often overlooked in non-alcoholic patients who are also at risk for malnutrition. In this paper we describe a case of a non-alcoholic 28-year-old female status post-sleeve gastrectomy who developed SNHL in the setting of thiamine deficiency and WE, with ongoing hearing impairment requiring hearing aids despite thiamine repletion.