Cluster Analysis to Identify Clinical Subtypes of Ménière's Disease.

OBJECTIVE: To identify distinct clinical subtypes of Ménière's disease by analyzing data acquired from a UK registry of patients who have been diagnosed with Ménière's disease. STUDY DESIGN: Observational study. METHODS: Patients with Ménière's disease were identified at secondary/tertiary care clinics. Cluster analysis was performed by grouping participants sharing similar characteristics and risk factors into groups based on a defined measure of similarity. RESULTS: A total of 411 participants were recruited into this study. Two main clusters were identified: participants diagnosed with ear infections (OR = 0.30, p < 0.014, 95% CI: 0.11-0.78) were more likely to be allocated in Cluster 1 (C1). Participants reporting tinnitus in both ears (OR = 11.89, p < 0.001, 95% CI: 4.08-34.64), low pitched tinnitus (OR = 21.09, p < 0.001, 95% CI: 7.47-59.54), and those reporting stress as a trigger for vertigo attacks (OR = 14.94, p < 0.001, 95% CI: 4.54-49.10) were significantly more likely to be in Cluster 2 (C2). Also, participants diagnosed with Benign Paroxysmal Positional Vertigo (OR = 13.14, <0.001, 95% CI: 4.35-39.74), autoimmune disease (OR = 5.97, p < 0.007, 95% CI: 1.62-22.03), depression (OR = 4.72, p < 0.056, 95% CI: 0.96-23.24), migraines (OR = 3.13, p < 0.008, 95% CI: 1.34-7.26), drug allergy (OR = 3.25, p < 0.029, 95% CI: 1.13-9.34), and hay fever (OR = 3.12, p < 0.009, 95% CI: 1.33-7.34) were significantly more likely to be clustered in C2. CONCLUSIONS: This study supports the hypothesis that Ménière's disease is a heterogeneous condition with subgroups that may be identifiable by clinical features. Two main clusters were identified with differing putative etiological factors. LEVEL OF EVIDENCE: 3 Laryngoscope, 2024.

Risk Factors for the Development of Bilateral Ménière's Disease.

OBJECTIVE: To identify key risk factors for the development of bilateral Ménière's disease. STUDY DESIGNS: Observational study. SETTING: Four NHS Trusts and four independent hospitals or clinics, within three distinct urban and rural regions within the United Kingdom (Norfolk, Leicestershire, and London). METHODS: Patients with Ménière's disease were identified at ENT or audiovestibular medicine secondary/tertiary care and specialist private clinics. A range of patient-reported data, questionnaire data, and clinical data (audiometric, radiological, and specialist balance testing data) was inputted into a bespoke database. A logistic regression model was used to identify potential risk factors for bilateral Ménière's disease compared with unilateral Ménière's disease. RESULTS: A total of 411 participants were recruited into this study, 263 from NHS Trusts and 148 from independent hospitals or clinics. In our cohort of patients, 22% of individuals were identified as having bilateral Ménière's disease. Two statistically significant independent variables were identified as risk factors for the development of bilateral Ménière's disease: the presence of psoriasis and a history of ear infections. CONCLUSIONS: Psoriasis and a history of ear infection have been identified as key risk factors for the development of bilateral Ménière's disease. It is anticipated that further work based on this finding will allow a better understanding of the underlying pathophysiological mechanisms that predispose to the development of Ménière's disease symptoms.

Motorist disorientation syndrome; clinical features and vestibular findings.

BACKGROUND: Motorist Disorientation Syndrome (MDS) is a term used to describe patients who primarily experience symptoms of dizziness/disorientation whilst in a motor car [21]. There is uncertainty about the relevance of vestibular dysfunction and whether this disorder could instead be a visually induced dizziness (VV) or part of a functional disorder similar to Persistent postural perceptual dizziness (PPPD). OBJECTIVE: We present the largest case-series to date of patients whose main complaint is of illusions of movement of self/vehicle when driving, characterising features of this group. METHODS: 18 subjects underwent detailed clinical assessment including validated questionnaires. A subset of patients underwent vestibular function testing. RESULTS: Mean onset age was 42 years, with no gender preponderance. Mean symptom duration was 6.39 years and was significantly longer in women. 50% reported moderate or severe handicap. Vestibular abnormalities were found in 60% of subjects tested. There was no significant difference in VSS total score between those with MDS and vestibular migraine (p = 0.154) with both having higher scores than healthy controls (p = 0.002, 0.000 respectively). CONCLUSIONS: MDS represents consistent symptoms, with high symptom burden, comparable to vestibular migraine. Vestibular deficits were not a consistent feature and similarities to VV and PPPD exist.

Lifestyle and dietary interventions for Ménière's disease.

BACKGROUND: Ménière's disease is a condition that causes recurrent episodes of vertigo, associated with hearing loss and tinnitus. Lifestyle or dietary modifications (including reducing the amount of salt or caffeine in the diet) are sometimes suggested to be of benefit for this condition. The underlying cause of Ménière's disease is unknown, as is the way in which these interventions may work. The efficacy of these different interventions at preventing vertigo attacks, and their associated symptoms, is currently unclear. OBJECTIVES: To evaluate the benefits and harms of lifestyle and dietary interventions versus placebo or no treatment in people with Ménière's disease. SEARCH METHODS: The Cochrane ENT Information Specialist searched the Cochrane ENT Register; Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid Embase; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 14 September 2022. SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs in adults with Ménière's disease comparing any lifestyle or dietary intervention with either placebo or no treatment. We excluded studies with follow-up of less than three months, or with a cross-over design (unless data from the first phase of the study could be identified).  DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were: 1) improvement in vertigo (assessed as a dichotomous outcome - improved or not improved), 2) change in vertigo (assessed as a continuous outcome, with a score on a numerical scale) and 3) serious adverse events. Our secondary outcomes were: 4) disease-specific health-related quality of life, 5) change in hearing, 6) change in tinnitus and 7) other adverse effects. We considered outcomes reported at three time points: 3 to < 6 months, 6 to ≤ 12 months and > 12 months. We used GRADE to assess the certainty of evidence for each outcome.  MAIN RESULTS: We included two RCTs, one related to diet, and the other related to fluid intake and sleep. In a Swedish study, 51 participants were randomised to receive 'specially processed cereals' or standard cereals. The specially processed cereals are thought to stimulate the production of anti-secretory factor - a protein that reduces inflammation and fluid secretion. Participants received the cereals for three months. The only outcome reported by this study was disease-specific health-related quality of life.  The second study was conducted in Japan. The participants (223) were randomised to receive abundant water intake (35 mL/kg/day), or to sleep in darkness (in an unlit room for six to seven hours per night), or to receive no intervention. The duration of follow-up was two years. The outcomes assessed were 'improvement in vertigo' and hearing.  As these studies considered different interventions we were unable to carry out any meta-analysis, and for almost all outcomes the certainty of the evidence was very low. We are unable to draw meaningful conclusions from the numerical results. AUTHORS' CONCLUSIONS: The evidence for lifestyle or dietary interventions for Ménière's disease is very uncertain. We did not identify any placebo-controlled RCTs for interventions that are frequently recommended for those with Ménière's disease, such as salt restriction or caffeine restriction. We identified only two RCTs that compared a lifestyle or dietary intervention to placebo or no treatment, and the evidence that is currently available from these studies is of low or very low certainty. This means that we have very low confidence that the effects reported are accurate estimates of the true effect of these interventions. Consensus on the appropriate outcomes to measure in studies of Ménière's disease is needed (i.e. a core outcome set) in order to guide future studies in this area and enable meta-analyses of the results. This must include appropriate consideration of the potential harms of treatment, as well as the benefits.

Vestibular migraine treatment: a comprehensive practical review.

Vestibular migraine is an underdiagnosed but increasingly recognized neurological condition that causes episodic vertigo associated with other features of migraine. It is now thought to be the most common cause of spontaneous (non-positional) episodic vertigo, affecting up to 1% of the population. A meta-analysis of preventative treatments for vestibular migraine was published in 2021, but the authors were unable to establish a preferred treatment strategy due to low quality of evidence and heterogeneity of study design and outcome reporting. Therefore, there remains a clinical need for pragmatic management guidelines specific to vestibular migraine using the available evidence. Here, we provide a practical review utilizing a systematic qualitative assessment of the evidence for abortive and preventative interventions in adults. The overall evidence base for vestibular migraine treatment is of low quality. Nevertheless, we provide practical treatment recommendations based on the available evidence and our experience to help guide clinicians treating patients with vestibular migraine. We also discuss how future clinical trials could be designed to improve the quality of evidence in this condition.

A link between frontal white matter integrity and dizziness in cerebral small vessel disease.

One in three older people (>60 years) complain of dizziness which often remains unexplained despite specialist assessment. We investigated if dizziness was associated with vascular injury to white matter tracts relevant to balance or vestibular self-motion perception in sporadic cerebral small vessel disease (age-related microangiopathy). We prospectively recruited 38 vestibular clinic patients with idiopathic (unexplained) dizziness and 36 age-matched asymptomatic controls who underwent clinical, cognitive, balance, gait and vestibular assessments, and structural and diffusion brain MRI. Patients had more vascular risk factors, worse balance, worse executive cognitive function, and worse ankle vibration thresholds in association with greater white matter hyperintensity in frontal deep white matter, and lower fractional anisotropy in the genu of the corpus callosum and the right inferior longitudinal fasciculus. A large bihemispheric white matter network had less structural connectivity in patients. Reflex and perceptual vestibular function was similar in patients and controls. Our results suggest cerebral small vessel disease is involved in the genesis of dizziness through its effect on balance.

The INVEST trial: a randomised feasibility trial of psychologically informed vestibular rehabilitation versus current gold standard physiotherapy for people with Persistent Postural Perceptual Dizziness.

BACKGROUND: Persistent postural perceptual dizziness (PPPD) is a common and disabling functional neuro-vestibular disorder. We aimed to determine the feasibility and acceptability of conducting a randomised controlled trial of cognitive-behavioural therapy informed vestibular rehabilitation (INVEST intervention) designed for persistent dizziness. METHODS: A two-armed parallel groups randomised feasibility study of INVEST vs. a time-matched gold standard vestibular rehabilitation (VRT) control. Participants with PPPD were recruited from a specialist vestibular clinic in London, UK. Participants were individually randomised using a minimisation procedure with allocation concealment. Measures of feasibility and clinical outcome were collected and assessed at 4 months. RESULTS: Forty adults with PPPD were randomised to six sessions of INVEST (n = 20) or gold standard VRT (n = 20). Overall, 59% of patients screened met the inclusion criteria, of which 80% enrolled. Acceptability of INVEST, as assessed against the theoretical framework of acceptability (TFA), was excellent and 80% adhered to all 6 sessions. There were small to moderate treatment effects in favour of INVEST across all measures, including dizziness handicap, negative illness perceptions, symptom focussing, fear avoidance, and distress (standardised mean difference [SMD]g = 0.45; SMDg = 0.77; SMDg = 0.56; SMDg = 0.50, respectively). No intervention-related serious adverse events were reported. CONCLUSIONS: The study results give strong support for the feasibility of a full-scale trial. Both arms had high rates of recruitment, retention, and acceptability. There was promising support of the benefits of integrated cognitive-behavioural therapy-based vestibular rehabilitation compared to gold standard vestibular rehabilitation. The study fulfilled all the a-priori criteria to advance to a full-scale efficacy trial. TRIAL REGISTRATION NUMBER: ISRCTN10420559.

Protocol for a randomised controlled feasibility study of psychologically informed vestibular rehabilitation for people with persistent dizziness: INVEST trial.

BACKGROUND: Dizziness is a common complaint that often persists and leads to disability and distress. Several cognitive and behavioural responses may contribute to the neurobiological adaptations that maintain persistent vestibular symptoms. This paper will present the protocol of a two-arm parallel group feasibility randomised controlled trial designed to determine whether a fully powered efficacy trial is achievable by examining the feasibility of recruitment, acceptability and potential benefits of an integrated cognitive behavioural therapy and vestibular rehabilitation (CBT-VR) treatment for people with persistent dizziness. METHODS: Forty adult patients will be recruited from a tertiary vestibular clinic with persistent movement-triggered dizziness for 3 months or longer who have moderate-high levels of dizziness handicap. Participants will be 1:1 randomised, using a minimisation procedure, to six sessions of either CBT-VR (intervention arm) or VR only (control arm). Measures will be collected at baseline and 4 months post randomisation. The primary feasibility outcomes include descriptive data on numbers meeting eligibility criteria, rates of recruitment, numbers retained post randomisation, treatment adherence and an acceptability questionnaire. Treatment effects on self-report outcomes will be estimated to determine that 95% confidence intervals for the effects are consistent with anticipated effects and minimum clinically important differences, and to provide information needed for the power calculation of an efficacy trial. A nested qualitative study will be conducted post-intervention (intervention group only) to explore the acceptability of the intervention and identify any areas in need of improvement. DISCUSSION: If a trial of CBT-VR is feasible, acceptability data will be used to enhance the intervention if needed and refine the multicentre RCT protocol. Future studies will need to consider the training required for other physiotherapists to deliver the intervention. TRIAL REGISTRATION: ClinicalTrials.gov, ISRCTN 10420559.

Is 'persistent postural perceptual dizziness' a helpful diagnostic label? A qualitative exploratory study.

BACKGROUND: Persistent Postural Perceptual Dizziness (PPPD) is a recently defined functional syndrome. In other functional disorders there has been concern that the label itself can have negative effects, but research on patient views of PPPD is lacking. OBJECTIVE: To understand patient views of the PPPD labelMETHODS:Semi-structured interviews were conducted with 13 people with PPPD and thematically analysed. RESULTS: Four themes were identified. Theme 1 reflects reassurance and validation received through a 'label'. Theme 2 reflects re-evaluation of illness-beliefs, with the diagnosis giving greater perception of control but also perception of having serious consequences. Theme 3 reflects difficulty understanding terminology. Participants rarely understood "persistent", "perceptual" and "postural". They did not tend to use the term "PPPD" to others or themselves. Some interpreted "persistent" as meaning "poor prognosis". Theme 4 reflects lack of psychological attribution, since participants normalised the experience of distress, but did not view this as part of PPPD. CONCLUSIONS: These data support the relevance of PPPD beyond simply classification. However patients found the components of the term itself confusing and did not tend to adopt it when relating their condition to others or themselves. Simplifying the nomenclature could facilitate shared understanding and management, even potentially influencing outcome.

EHealth and Its Role in Supporting Audiological Rehabilitation: Patient Perspectives on Barriers and Facilitators of Using a Personal Hearing Support System With Mobile Application as Part of the EVOTION Study.

BACKGROUND: Hearing loss is a major public health challenge. Audiology services need to utilise a range of rehabilitative services and maximise innovative practice afforded by technology to actively promote personalized, participatory, preventative and predictive care if they are to cope with the social and economic burden placed on the population by the rapidly rising prevalence of hearing loss. Digital interventions and teleaudiology could be a key part of providing high quality, cost-effective, patient-centred management. There is currently very limited evidence that assesses the hearing impaired patient perspective on the acceptance and usability of this type of technology. AIM: This study aims to identify patient perceptions of the use of a hearing support system including a mobile smartphone app when used with Bluetooth-connected hearing aids across the everyday life of users, as part of the EVOTION project. METHODS: We applied a questionnaire to 564 participants in three countries across Europe and analysed the following topics: connectivity, hearing aid controls, instructional videos, audiological tests and auditory training. KEY FINDINGS: Older users were just as satisfied as younger users when operating this type of technology. Technical problems such as Bluetooth connectivity need to be minimised as this issue is highly critical for user satisfaction, engagement and uptake. A system that promotes user-controllability of hearing aids that is more accessible and easier to use is highly valued. Participants are happy to utilise monitoring tests and auditory training on a mobile phone out of the clinic but in order to have value the test battery needs to be relevant and tailored to each user, easy to understand and use. Such functions can elicit a negative as well as positive experience for each user. CONCLUSION: Older and younger adults can utilise an eHealth mobile app to complement their rehabilitation and health care. If the technology works well, is tailored to the individual and in-depth personalised guidance and support is provided, it could assist maximisation of hearing aid uptake, promotion of self-management and improving outcomes.

The Role of Prediagnosis Audiovestibular Dysfunction Versus Distress, Illness-Related Cognitions, and Behaviors in Predicted Ongoing Dizziness Handicap.

OBJECTIVE: People with chronic vestibular diseases experience variable degrees of self-perceived disability. However, longitudinal data examining the predictive validity of relevant clinical variables alongside psychological variables are limited. The present study examined whether these factors predict self-reported dizziness handicap 3 months after assessment and diagnosis. METHODS: Patients were recruited from a waiting list of a tertiary neuro-otology clinic and completed standardized mood, cognitive, behavioral, and dizziness handicap questionnaires before and 3 months after their initial consultation and diagnosis. All patients were clinically assessed and underwent comprehensive audiovestibular investigations. RESULTS: Seventy-three percent of participants responded at follow-up (n = 135, 73% female, mean [standard deviation] age = 54.23 [17.53] years), of whom 88% were diagnosed with a neurotological condition. There were significant improvements in handicap, depression, and anxiety at 3 months. Thirty (22%) of 135 showed clinically meaningful improvement in handicap. The percentage of case-level depression and anxiety remained the same. Negative illness perceptions and symptom responses reduced, although participants still tended to view their condition negatively. Vestibular tests and type of diagnosis were not associated with self-reported handicap. Most baseline psychological variables significantly correlated with handicap at 3 months. When adjusting for baseline handicap and demographics, the baseline psychological variables only explained a significant ~3% of the variance in dizziness handicap at follow-up, with baseline handicap explaining most of the variance. All-or-nothing behavior was the most significant predictor. CONCLUSIONS: Tertiary patients with vertigo and dizziness report negative illness perceptions and cognitive and behavioral responses to symptoms that are associated with self-reported handicap over time. Future studies are needed to investigate whether targeting these factors alongside traditional treatment approaches improves handicap in patients with chronic dizziness.

Vestibular deficits and psychological factors correlating to dizziness handicap and symptom severity.

OBJECTIVE: To determine the relative contribution of demographic variables, objective testing and psychological factors in explaining the variance in dizziness severity and handicap. METHODS: One-hundred and eighty-five consecutive patients on the waiting list to attend a diagnostic appointment in a tertiary neuro-otology clinic with a primary complaint of vertigo or dizziness completed a cross-sectional survey. Primary outcomes were the Dizziness Handicap Inventory and the vertigo subscale of the Vertigo Symptom Scale-Short Form. Psychological questionnaires assessed anxiety and depressive symptoms, illness perceptions, cognitive and behavioural responses to symptoms, beliefs about emotions and psychological vulnerability. Patients also underwent standardised audio-vestibular investigations and tests to reach a diagnosis at appointment. RESULTS: Objective disease characteristics were not associated with handicap and only the presence of vestibular dysfunction on one test (caloric) was associated with symptom severity. Almost all the psychological factors were correlated with dizziness outcomes. The total hierarchical regression model explained 63% of the variance in dizziness handicap, and 53% was explained by the psychological variables. The regression model for symptom severity explained 36% of the variance, and 30% was explained by the psychological factors. In adjusted models, factors associated with dizziness handicap included age, female gender, distress, symptom focusing, embarrassment, avoidance, and beliefs about negative consequences. Fear avoidance was the only independent correlate in the fully adjusted model of symptom severity. CONCLUSION: Self-reported dizziness severity and handicap are not correlated with clinical tests of vestibular deficits but are associated with psychological factors including anxiety, depression, illness perceptions, cognitive and behavioural responses.

Integrating mental and physical health assessment in a neuro-otology clinic: feasibility, acceptability, associations and prevalence of common mental health disorders.

People with persistent physical symptoms are at risk of psychological symptoms, although recognition in medical settings is low. This is a retrospective observational study of 954 patients in a hospital outpatient neuro-otology clinic in order to assess the feasibility and acceptability of an electronic informatics system for collection of patient-reported outcomes, with real-time feedback to guide clinical care and describe the prevalence of anxiety and depressive symptoms.The proportion of patients successfully completing the screen was high (70%). The decline rate was low (5%). The most common reason to decline was lack of confidence with technology. The prevalence of probable depression was 21% and for probable anxiety was 29%. Suicidal ideation was present in 5%. Anxiety and depression were highly correlated to dizziness specific outcome measures (p<0.01).Electronic screening is feasible and acceptable to patients and staff in this setting, helping to identify service needs, inform care and monitor outcomes.

Challenges and Strengths of Multidisciplinary Research in Audiology: The EVOTION Example.

Purpose The EU-funded research project EVOTION has brought together clinical, technical, and public health experts with the aim to offer a solution for the holistic management of hearing loss. This report presents the challenges, strengths, and key take-home messages of working in this multidisciplinary consortium. Method Fifteen consortium members completed an online survey with 6 open-ended questions. Responses were analyzed using a thematic approach. Results Analysis identified 4 main themes: (a) communication, that is, cross-disciplinary communication difficulties but also range of expertise; (b) opportunities, that is, innovation, learning, and collaborations; (c) technology, that is, technical requirements and data collection and management issues; and (d) local constraints, that is, institutional limitations, resources, and planning. Conclusions Although the challenges reported differed by country and specialty, there was consensus about the value, expertise, and opportunities of the project. It is recommended that in future similar multidisciplinary projects in audiology, researchers establish a common language and assess technical requirements and local constraints prior to initiating research activities.

MRI findings in vestibular paroxysmia - An observational study.

BACKGROUND/OBJECTIVES: Vestibular paroxysmia (VP) presents as episodic vertigo believed to be caused by neurovascular cross-compression (NVCC) of the vestibulocochlear nerve. We investigated whether NVCC occurred at a higher rate in VP, compared with controls and whether angulation of the nerve, the vessel involved and location of the point of contact were significant features. METHODS: Retrospective analysis was conducted of MR imaging performed in patients with VP and also patients with unilateral tinnitus (in whom the asymptomatic side was used as a control). Two independent, blinded reviewers assessed each case. RESULTS: Nine patients with VP and 20 patients with unilateral tinnitus were included. NVCC was demonstrated in all 9 VP patients (100%), compared with 9 of the controls (45%), p = 0.0049. NVCC was mostly caused by a branch of the anterior inferior cerebellar artery (AICA). Nerve angulation at the point of contact occurred in 5 of the cases (44%), but in none of the controls (specificity = 100%), p = 0.0053. There was no correlation between site of contact and VP. CONCLUSION: Our study supports the concept of NVCC in VP and additionally suggests that nerve angulation may be a specific feature. Neurovascular contact remains a common phenomenon in asymptomatic patients and therefore correlation with neuro-otology assessment remains essential.

Big Data for Sound Policies: Toward Evidence-Informed Hearing Health Policies.

PURPOSE: The scarcity of health care resources calls for their rational allocation, including within hearing health care. Policies define the course of action to reach specific goals such as optimal hearing health. The process of policy making can be divided into 4 steps: (a) problem identification and issue recognition, (b) policy formulation, (c) policy implementation, and (d) policy evaluation. Data and evidence, especially Big Data, can inform each of the steps of this process. Big Data can inform the macrolevel (policies that determine the general goals and actions), mesolevel (specific services and guidelines in organizations), and microlevel (clinical care) of hearing health care services. The research project EVOTION applies Big Data collection and analysis to form an evidence base for future hearing health care policies. METHOD: The EVOTION research project collects heterogeneous data both from retrospective and prospective cohorts (clinical validation) of people with hearing impairment. Retrospective data from clinical repositories in the United Kingdom and Denmark will be combined. As part of a clinical validation, over 1,000 people with hearing impairment will receive smart EVOTION hearing aids and a mobile phone application from clinics located in the United Kingdom and Greece. These clients will also complete a battery of assessments, and a subsample will also receive a smartwatch including biosensors. Big Data analytics will identify associations between client characteristics, context, and hearing aid outcomes. RESULTS: The evidence EVOTION will generate is relevant especially for the first 2 steps of the policy-making process, namely, problem identification and issue recognition, as well as policy formulation. EVOTION will inform microlevel, mesolevel, and macrolevel of hearing health care services through evidence-informed policies, clinical guidelines, and clinical care. CONCLUSION: In the future, Big Data can inform all steps of the hearing health policy-making process and all levels of hearing health care services.

Clinical Subtyping of Ménière's Disease.

Fundamentally, Ménière's disease is a constellation of symptoms and, as such, may represent the final common pathway for a number of disease processes, as opposed to being the consequence of a single isolated pathology. Within this type of consideration, much can be learned regarding the etiology, presentation, prognosis, and treatment of these individual conditions by applying subtyping techniques currently employed to better understand similar disease processes that are encountered in other allied fields of medicine. This commentary proposes the principles, required processes, and benefits of subtyping for Ménière's disease.

Clinical validation of a public health policy-making platform for hearing loss (EVOTION): protocol for a big data study.

INTRODUCTION: The holistic management of hearing loss (HL) requires an understanding of factors that predict hearing aid (HA) use and benefit beyond the acoustics of listening environments. Although several predictors have been identified, no study has explored the role of audiological, cognitive, behavioural and physiological data nor has any study collected real-time HA data. This study will collect 'big data', including retrospective HA logging data, prospective clinical data and real-time data via smart HAs, a mobile application and biosensors. The main objective is to enable the validation of the EVOTION platform as a public health policy-making tool for HL. METHODS AND ANALYSIS: This will be a big data international multicentre study consisting of retrospective and prospective data collection. Existing data from approximately 35 000 HA users will be extracted from clinical repositories in the UK and Denmark. For the prospective data collection, 1260 HA candidates will be recruited across four clinics in the UK and Greece. Participants will complete a battery of audiological and other assessments (measures of patient-reported HA benefit, mood, cognition, quality of life). Patients will be offered smart HAs and a mobile phone application and a subset will also be given wearable biosensors, to enable the collection of dynamic real-life HA usage data. Big data analytics will be used to detect correlations between contextualised HA usage and effectiveness, and different factors and comorbidities affecting HL, with a view to informing public health decision-making. ETHICS AND DISSEMINATION: Ethical approval was received from the London South East Research Ethics Committee (17/LO/0789), the Hippokrateion Hospital Ethics Committee (1847) and the Athens Medical Center's Ethics Committee (KM140670). Results will be disseminated through national and international events in Greece and the UK, scientific journals, newsletters, magazines and social media. Target audiences include HA users, clinicians, policy-makers and the general public. TRIAL REGISTRATION NUMBER: NCT03316287; Pre-results.