Is ‘persistent postural perceptual dizziness’ a helpful diagnostic label? A qualitative exploratory study

1 Introduction

Persistent postural-perceptual dizziness (PPPD) is a newly defined diagnostic syndrome presenting with one or more symptoms of dizziness, unsteadiness, or non-spinning vertigo that are present on most days for three months or more and are exacerbated by upright posture, active or passive movement, and exposure to moving or complex visual stimuli [21]. It is considered within the spectrum of other ‘persistent physical symptoms’ or ‘functional’ neurological disorders, where symptoms represent a change in ‘functional’ rather than ‘structural’ abnormality of bodily systems [5, 23]. The exact pathophysiology of functional vestibular disorders such as PPPD is not yet clear. However, the processes are known to involve normal physiological and behavioural responses to an acute postural threat, which become inappropriately sustained after its remission [6, 20]. The classification of vestibular disorders emphasises the need to make the diagnosis based on positive features of the patient history rather than by the absence of structural pathology and independent of any psychiatric conditions that may coexist [21].

The term ‘Persistent Postural Perceptual Dizziness’ unifies the key features of its various overlapping predecessors, such as chronic subjective dizziness, phobic postural vertigo, space-motion discomfort, and visual vertigo [21, 22]. It has been recognised by the Word Health Organisation [27] and recently established International Classification of Vestibular Disorders [21]. The new name was chosen by a group of clinicians and academics with the aim of providing an aetiologically neutral but positive diagnostic term that lacks causal inferences about whether the symptoms have arisen from a structural lesion or a purely ‘psychogenic’ process [18].

Once recognised, treatment starts with information counselling for the patient about the diagnosis, followed by recommending appropriate therapy tailored for their needs. Treatment options include vestibular physiotherapy, medication and cognitive-behavioural therapy, all of which are medium term interventions strongly dependent for success on patient engagement. Thus, the identification of patient beliefs, expectations and attitudes is an essential pre-requisite for shared decision-making and developing a plan of care.

The importance of diagnostic labels has long been acknowledged to go beyond the simple utility of classification and therapeutic algorithms. They carry meaning out of the clinic and into the real world, where expectations, explanations of illness experience and the reactions of others are pinned to them. In short, calling an illness by a name changes the illness experience and has been shown to influence outcome and potential for social support [10, 16]. The ways in which people with PPPD perceive themselves, label their symptoms and appraise stressors may potentially perpetuate or exacerbate their symptoms [14]. Labels can also lead to issues for healthcare professionals who fear giving an unwelcome diagnosis might lead to conflict. Also there is a theoretical concern that the use of terms such as ‘persistent’ could influence beliefs about possible outcomes. However, on the other hand, finding a label that is in harmony with the self-perception of the condition can provide meaning, emotional relief and recognition, as well as facilitation of therapeutic engagement.

Terms used to describe similar phenomena in the past, such as ‘medically unexplained symptoms’, that were quickly adopted without first examining patient preferences, have in some cases garnered negative reactions [15, 17], led to further stigma and hampered relationships with patient groups. This outcome should clearly be avoided where possible.

Since PPPD is a new diagnostic label, little is known about how it is perceived by patients. The published paper proposing the term does not describe any direct patient involvement in the process of devising the nomenclature. It is therefore not clear if the label is disabling or enabling, or what the label implies from the patient perspective. The present study was therefore designed to develop further the work of the classification committee by exploring patient perceptions of this term.

2 Methods

This was a qualitative study. All participants provided written informed consent. The study was approved by the National Heath Research Authority Service (19/LO/1482). The study ran from October 2019 to January 2020 and is registered at clinicaltrial.gov (NCT04260568).

3 Results

The sample included 10 women (77%) and 3 men (23%), with a median age of 51 years (IQR 39 – 54; range 18–82). Participants had a mean duration of symptoms of 7 years (SD 4.5; range 6 months – 14 years). Seven (54%) participants were white British and two (15.4%) were of Other White background, others were from other ethnicities including Black British, Asian British, Black Caribbean and mixed backgrounds. Table 1 summarises scores on self-report questionnaires completed by ten of the participants during their consultation that indicated that the sample was, on average, experiencing moderate levels of dizziness interference. Three participants reported recent or longstanding severe disability indicating an inability to work, and six participants scored above the threshold for probable anxiety.

We identified 4 themes and 11 subthemes, illustrated in Fig. 1. Although we present the themes and subthemes separately, they are, by nature, strongly inter-related.

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Fig. 1

Four themes were identified, shown in this figure with associated subthemes listed under each theme.

4 Discussion

This is the first study to explore the perceptions of the diagnostic label ‘Persistent Postural Perceptual Dizziness’ in people with this condition. Four themes were identified reflecting the complex nature of reassurance and illness validation, the ways in which patients re-evaluate beliefs about their condition and appraise their emotions, and struggle to understand terminology. These data can inform holistic approaches for clinicians treating patients with PPPD and scientists with interest in taxonomy of vestibular disorders.

The identified (sub)themes were strongly inter-related. For example, the perceived beneficial ‘illness validation’ of receiving a diagnosis (theme 1) was offset by the effects of obscure terminology lacking legitimacy (theme 3), which exacerbated distress and frustration (theme 4). Clinicians may fear diagnosis might lead to worse outcomes through self-fulfilling prophecies of non-recovery, validating sickness roles and providing a psychosomatic illness label. Thus, understanding the ways persons with PPPD perceive themselves, label their symptoms and appraise stressors is crucial to make sense of how people experience and manage their condition.

Participants in this study frequently attributed their symptoms to PPPD and a diagnosis was perceived as helpful since it brought an end to the burden of uncertainty and signalled a course of action to follow. The ‘common sense model of self-regulation in response to health threats’ provides a framework in which to interpret these findings [13, 14]. It is normal, when experiencing symptoms or bodily sensation, to want to find a label or diagnosis to be able to understand these symptoms. Likewise receipt of an illness label or diagnosis can motivate individuals to find symptoms or bodily sensations in line with that label [3, 12]. The ‘common sense model’ proposes that lay interpretations of information and personal experiences directly influence coping strategies, which in turn influence outcomes.

After the diagnosis, participants had a greater perception that the condition could be kept under control, although usually not cured, and had a greater understanding of their role in achieving this. However, participants had negative beliefs about the expected time-course and consequences of PPPD. These representations were usually a result of their own experience over time and how the condition had already impacted them physically and socially. Some of the participants also related the term ‘persistent’ to a negative future outcome. Nevertheless, there were signs of participants willingness to re-evaluate these beliefs as time progresses. A previous qualitative study focused on the impact of PPPD on personal, social and work life and also highlighted the need to consider the contextual factors to facilitate a person-centred approach [19].

The qualitative study by Sezier et al. [19] also showed that participants with PPPD struggle to find the vocabulary that encapsulates their experience which is perceived as embarrassing and frustrating. The current results extend this by showing how the label itself was perceived as illegitimate and that participants rarely understood the meaning of the individual constituent word elements. This threatens the social validation of the diagnosis evidenced by participants’ unwillingness to use ‘Persistent Postural Perceptual Dizziness’ to explain the illness to others or when thinking about the condition themselves. This is something that could potentially change as the condition becomes more widely recognised in broader society.

Comparisons could be drawn with the diagnostic label Benign Paroxysmal Positional Vertigo (BPPV). Not only could the acronyms be easily mixed up, but BPPV is an equally complicated term, with constituent words which in our experience are rarely fully understood or used by patients. We are not aware of any studies with data on patient perceptions of the term BPPV, but anecdotally as clinicians we frequently encounter patients describing BPPV as ‘crystals in my ears’ or some such substitute rather than using the precise technical term because of its unwieldiness. Future work could examine patients’ perceptions of the term BPPV by way of comparison. However, we would hypothesise that health beliefs are a less important influence on outcomes in BPPV than in PPPD, since psychosomatic mechanisms are not thought to play a role in BPPV in most cases.

Participants reported broad ranging impacts of dizziness on their mood and functioning, consistent with the wider literature [7, 11]. The descriptions of anxiety, fear of falling and reduced activity are consistent with pathophysiological [21] and cognitive-behavioural [26] models of PPPD. Despite this, participants did not always acknowledge bidirectional relationships between dizziness and psychological state. More than half of participants in this study scored above the categorical threshold for clinically significant anxiety and it is important to reduce the stigma around mental health. Nevertheless many participants viewed this as pathologizing the experience of negative emotions which occur in response to challenging and disruptive symptoms. These findings are unlikely to be unique to PPPD, since Coventry et al. [4] also found a preference amongst both patients and practitioners to normalise the experience of distress in long term conditions. Considering the severity of illness distress, its duration, and consequential impact on function is therefore important to identify individuals who would benefit from clinical intervention [9]. Incorporating education about adaptive acute anxiety responses and integrated models into the explanation can also aid the therapeutic encounter.

The Barany Society has worked hard to standardise nomenclature for vestibular disorders and oversee development of the International Classification of Vestibular Disorders [1]. The adoption of the term has no doubt stimulated research into this common clinical presentation and the patients in this study recognised and appreciated the importance of this research. Developing formal diagnostic criteria has been useful in both the clinical and research settings. The name was chosen by a committee of clinicians and academics with varied perspectives but there was no mention of any direct patient involvement in the process of devising the nomenclature [21]. The current data suggests consideration of simpler terminology in future iterations of this condition’s classification. Although the term ‘perceptual’, for example, fulfils the requirement of neutrality, it lacks specificity since symptoms are by their nature ‘perceptual’ and is not well understood by patients. It also could be understood to imply that there is no pathophysiological basis for the experience, although our patients did not report this concern. Experiences of stigma in the participants were also present due to widespread unfamiliarity with the condition. It could therefore be beneficial to bring terminology in line with other areas which are starting to generate greater awareness, such as ‘functional’ neurological disorders.

When considering nomenclature it may not be realistic to find a term everyone is happy with. Rather the question could be what term is associated with the smallest ‘number needed to offend’, which was the method described by J. Stone et al. [25] for functional neurological disorder. Stone’s concept of ‘offence’ was determined by whether the different terms implied the patient was ‘putting on’ or ‘imagining’ their symptoms or that they were ‘mad’. The current data expands this concept since participants expressed the desire for a label to garner social support. S. Noble et al. [16] found that university students were more likely to respond sympathetically and supportively to hypothetical scenarios about a close friend when a label of chronic fatigue syndrome was used compared to no-label. Future quantitative research could therefore consider not only what label gets the best outcome, but what ‘outcome’ is considered important for patients.

A strength of the study was that the interviewers were medical students rather than healthcare professionals allowing the participants to open up about their true feelings and not to be influenced by the interviewer’s professional background or concern that critical comments about the diagnosis might offend or upset the staff responsible for their care. The sample size was small and slightly biased towards females, but comprised participants with varied racial/ethnic backgrounds, wide range of ages, illness duration, disability and anxiety levels. The purposive sampling does have the potential to bias participation. The study was also conducted in one NHS hospital in London and non-English speakers were excluded thus limiting representation of an even more diverse group. It is also important to acknowledge that this study explored perceptions of a specific patient group who had been assessed at a specialist centre and that this cannot be assumed to be representative of the experience of other patients with PPPD in other settings. Further research should explore in-depth cultural differences in the representations of and metaphors used to describe PPPD and how this influences dizziness management, and the perceptions of patients with PPPD in other healthcare settings. Our participants had had the label for less than two years, since the label itself is not much older than this.

Some of the issues identified by our study participants may evolve and lessen as the term “beds down” and is in greater use in different communities.

In conclusion, these data support the relevance of PPPD beyond the simple utility of classification. Having a diagnosis and label for functional vestibular symptoms is helpful to individuals since it provides relief and validation and a label that fits the symptoms of this population. Participants also support the need for research into the condition that the label has facilitated. However there can be unintended negative consequences to labels. Also, ideally, a label will be one that empowers individual sufferers to understand and manage their condition and explain it to those around them when necessary. Clinicians should work collaboratively with patients to explore their illness beliefs, clarify their understanding and the acceptability of the label and what it implies for them. Scientific committees for the classification of vestibular disorders should also consider patient-public representation in future when making decisions about terms used to diagnose and classify illnesses.