Continuing Education Activity

Persistent postural-perceptual dizziness is a common yet challenging chronic vestibular disorder that can lead to long-term disability, often without a clearly identifiable cause. This condition is characterized by persistent dizziness, unsteadiness, and imbalance present on most days for at least 90 days, with symptoms often worsening during standing, walking, upright posture, or exposure to visually complex environments. Because imaging and other diagnostic tests are frequently normal, recognition and diagnosis can be difficult and rely heavily on clinical history and established diagnostic criteria. This activity reviews the epidemiology, pathophysiology, clinical features, diagnostic approach, differential diagnosis, prognosis, and evidence-based management of persistent postural-perceptual dizziness. Treatment strategies, including vestibular rehabilitation, cognitive-behavioral therapy, and pharmacologic options, are discussed, along with preventive considerations, common comorbidities, and the critical role of the interprofessional healthcare team in optimizing patient outcomes and education.

Objectives:

• Identify patients with signs and symptoms of persistent postural-perceptual dizziness.
• Apply comprehensive strategies to precisely diagnose persistent postural-perceptual dizziness and any associated overlapping conditions.
• Implement evidence-based treatment options for patients experiencing persistent postural-perceptual dizziness.
• Collaborate with the interprofessional team to educate, treat, and monitor patients with persistent postural-perceptual dizziness to improve patient outcomes.

Introduction

In 2017, the Barany Society's Committee for the Classification of Vestibular Disorders introduced diagnostic criteria for persistent postural-perceptual dizziness (PPPD), which is classified as a chronic functional vestibular disorder in the International Classification of Vestibular Disorders.[1] While PPPD was introduced as a new term, the disorder's core features date back to the 19th century. In the 1870s, 3 German clinicians—Benedikt, Cordes, and Westphal—described syndromes of dizziness and discomfort in motion-rich environments, accompanied by autonomic arousal, anxiety, and avoidance of provocative circumstances. These clinicians described symptoms related to postural control, locomotion, and conscious appraisal of spatial orientation, with Westphal's term agoraphobia. A century later, additional descriptions emerged, including disorientation and aberrant motion sensations in specific circumstances such as supermarket syndrome, space phobia, motorist's vestibular disorientation, visually induced motion, and physiologic height vertigo.[2][3][4][5][6]

Recent descriptions of PPPD as a chronic and disabling disorder are characterized by persistent dizziness, unsteadiness, and imbalance, which pose diagnostic and management challenges for clinicians since it often arises without an identifiable cause.[7] The pathophysiology of PPPD is not fully understood, but it is believed to involve complex interactions between the sensory systems and the central nervous system.[8] Critical elements of PPPD include sensory mismatch, central nervous system hypersensitivity to stimuli, and maladaptive changes in how the brain processes sensory information.[9] Neurotransmitter dysfunction may also contribute to the persistence of PPPD symptoms, including unsteadiness, dizziness, or non-vertiginous dizziness, present on most days for at least 90 days and exacerbated by sitting upright, standing, walking, and visually complex stimuli.[1] PPPD likely overlaps with other vestibular disorders, migraines, and various psychological conditions such as generalized anxiety disorder and panic disorder. [10] 

PPPD is classified as a chronic vestibular disorder.[11] The condition is more common in women than in men. Imaging and testing are often unremarkable. Nonetheless, advances in neuroimaging techniques have revolutionized researchers' ability to explore structural and functional brain changes associated with PPPD.[12] Treatment is often multimodal, including cognitive-behavioral therapy, physical therapy, and serotonergic medications.[13] Challenges arise with medications, as they may provide only partial, temporary relief.[14] Other PPPD challenges include the subjectivity of symptoms and the impact on quality of life.[15][16][17] Treatment of patients with PPPD requires a multidisciplinary approach including integration of pharmacotherapy, vestibular rehabilitation, and psychological support.

Etiology

The direct cause of the disorder is unknown, but it is believed to result from a disruption within or between the visual and postural control systems mechanisms.[18] The initial trigger may be neuro-otologic, metabolic, allergic, or psychological. Symptoms commonly occur after a vestibular insult, such as vestibular neuritis, BPPV, Meniere disease, or other predisposing medical conditions. PPPD can reflect incomplete recovery after a vestibular event or chronic problems between episodic vestibular events. Psychological factors also contribute to the development of PPPD, as it is frequently observed in patients with high anxiety, neuroticism, depression, and heightened body vigilance. 

Many clinical features of PPPD stem from the physiological effects of an acute balance disruption.[19] When vestibular failure occurs, shifting to visual and postural input strategies is an adaptive response. However, if re-adaptation does not occur after the vestibular issue resolves—or if the dysfunction persists—this can lead to habitual poor postural and gait patterns. These patterns include stiffened walking, shorter strides, and heightened visual dependence. Such behaviors are attempts to respond to a perceived postural threat that is no longer present, which then become maladaptive.[8]

Epidemiology

Validated incidence and prevalence data are difficult to obtain for a disorder that has only recently been redefined. PPPD is the most common chronic vestibular disorder among people aged 30 to 50.[18][20] Females are affected more often than men, with a ratio of up to 4:1.[21][22] A population-based primary care study conducted in the United Kingdom found that 4% of all patients registered with a general practitioner experienced ongoing dizziness, with the majority being severely affected.[23] In tertiary dizziness centers, the second most common diagnosis—representing about 15% to 20% of all patients—is either phobic postural vertigo or chronic subjective dizziness, both of which are conceptual predecessors of PPPD presentations.[24]

Pathophysiology

The exact pathophysiology is not fully understood. The pathophysiology of PPPD may be rooted in sensory mismatch, with a conflict among visual, vestibular, and proprioceptive inputs, leading to persistent dizziness and unsteadiness.[8][19] PPPD is thought to involve 3 key mechanisms: stiffened postural control, a shift in spatial orientation information to favor visual over vestibular cues, and failure of higher cortical mechanisms to modulate the first 2 processes.[25] Two hypotheses have been proposed to explain the failure to readapt after a precipitating event: Pavlovian conditioning incorporated into cognition and behavior [26] or a deficiency in cortical processes that subserve locomotion and spatial orientation, as evidenced by neuroimaging studies.[27]

Individuals with a neurotic temperament or pre-existing anxiety may be more susceptible. After a vestibular injury, a medical event, or acute psychological distress, patients are believed to become dependent on visual and somatosensory cues, maintain heightened environmental vigilance, and experience changes in posture. This situation is worsened in individuals with high anxiety and body awareness, as they tend to focus more on their surroundings and pay closer attention to their posture to compensate for their perceived dizziness.[18] Thus, changes in posture, self-motion, and visually demanding environments often provoke symptoms of dizziness, unsteadiness, and non–room-spinning vertigo.[21] 

History and Physical

History

Obtaining a detailed history is crucial for patients with PPPD because their symptoms are central to the diagnosis. Due to the links with psychological factors, questions about anxiety and depression should be included in a clinician's history-taking. Understanding that PPPD is not diagnosed by exclusion is important, and the diagnostic criteria are inclusive and quite precise. Vague or nonspecific complaints should be avoided when confirming or excluding PPPD. Additionally, PPPD can coexist with other conditions; for instance, sensations of veering or swaying are common, but falls or near falls are rare. Tests are primarily used to exclude other conditions rather than to confirm PPPD.

Physical Examination

Patients with PPPD generally demonstrate normal findings on physical and neurological examination. The Head Impulse, Nystagmus, and Test of Skew (HINTS) examination is primarily indicated in acute presentations of dizziness and is less useful in chronic settings; accordingly, results are typically normal in PPPD.[11] 

On a gait examination, a patient may sway, demonstrating a vestibular imbalance or disruption in compensatory mechanisms, but they often do not fall. Ruling out other diagnoses or assessing for comorbid conditions is important.

Evaluation

The Bárány Society criteria for diagnosing PPPD include five specific requirements, all of which must be met.[1]

• One or more symptoms, such as dizziness, unsteadiness, or non-spinning vertigo, are present on most days for 3 months or more

  • Symptoms last for prolonged (hours-long) periods, but may wax and wane in severity
  • Symptoms need not be present continuously throughout the entire day

• Persistent symptoms occur without specific provocation, but are exacerbated by 3 factors:

  • Upright posture
  • Active or passive motion without regard to direction or position
  • Exposure to moving visual stimuli or complex visual patterns

• The disorder is precipitated by conditions that cause vertigo, unsteadiness, dizziness, or balance problems, including acute, episodic, or chronic vestibular syndromes, other neurologic or medical illnesses, or psychological distress.

  • When the precipitant is an acute or episodic condition, symptoms settle into the pattern of criterion A as the precipitant resolves. Still, they may occur intermittently at first, and then consolidate into a persistent course.
  • When the precipitant is a chronic syndrome, symptoms may develop slowly at first and worsen gradually.

• Symptoms cause significant distress or functional impairment.
• Another disease or disorder does not account for the symptoms any better.

The diagnosis is made based on the history and the criteria listed above. A physical and neurological examination is generally unremarkable. To assess for comorbid conditions, the workup may include a HINTS test, cervical and ocular vestibular evoked myogenic potentials, brain neuroimaging with magnetic resonance imaging or computed tomography, and a pure-tone audiogram.[28] 

Discrepancies often exist between clinical examination results and subjective symptoms. In patients with PPPD, impaired function in the precuneus and cuneus may lead to poor integration of visual and vestibular information, resulting in persistent dizziness and imbalance. Functional magnetic resonance imaging may show decreased connectivity between the precuneus and precentral gyrus, which may correlate with worsened symptoms during standing or movement, whether active or passive.[20][29] The precuneus is involved in visuospatial imagery, episodic memory, and self-processing, whereas the cuneus primarily handles visual processing. Both are adjacent, specialized regions on the medial surface of the brain's cerebral hemispheres, separated by the parieto-occipital sulcus.

Treatment / Management

Treatment of PPPD does not rely on a single method. Understanding that dizziness may arise from central, peripheral, and vascular conditions is essential. Treatment approaches include the following:

• Vestibular rehabilitation [15]

  • Exercise to improve balance and reduce dizziness
  • Clear guidance on optimal duration, intensity, and specific exercises is lacking

• Cognitive-behavioral therapy has been shown to augment vestibular therapy by decreasing the maladaptive cycle of anxiety and balance control.[16][30]

• Pharmacotherapy: The use of these treatments for this condition remains highly uncertain.[14] 

  • Selective serotonin reuptake inhibitors
  • Vestibular suppressants

Differential Diagnosis

For PPPD to be clinically diagnosed, all 5 Barany Society criteria must be met. Failure to meet all 5 criteria should prompt clinicians to consider other medical conditions. In the workup of a dizzy patient, clinicians should also consider post-concussive syndrome, stroke, deconditioning, BPPV, vestibular migraine, panic attacks, Meniere disease, cardiac dysrhythmias, autonomic disorders, generalized anxiety, peripheral neuropathy, semicircular canal dehiscence, neurodegenerative disorders, functional gait disorder, and hypotension.[21][31]

Prognosis

Limited research exists to determine whether PPPD is a lifelong condition. However, patients who undergo vestibular balance rehabilitation therapy and cognitive-behavioral therapy, in addition to pharmaceutical management, report better quality of life and a faster return to normal activities than those who do not receive any treatment.[32]

Studies suggest that those who receive intervention acutely following a triggering event fare better than those who receive no intervention.[21]

Complications

Patients with this condition may experience heightened anxiety, depression, and a heightened awareness of their bodies. PPPD can lead to various secondary complications, including neck stiffness, gait disorders, fear of falling, agoraphobia, fatigue, and dissociation. Clinicians should recognize that PPPD is not a psychiatric disorder; however, psychiatric issues can arise as a result of PPPD, worsening the patients' overall experience.[21] 

Patients may develop a fear of leaving home to avoid situations that worsen their symptoms.[33]

Postoperative and Rehabilitation Care

Vestibular therapy and cognitive-behavioral therapy are the most effective options for helping patients regain their ability to perform daily activities. The sooner a patient receives these therapies, the better the outcome is likely to be. Vestibular therapy is particularly useful for managing issues related to unsteadiness and balance. Additionally, it can help patients manage situations that may worsen their symptoms. Meanwhile, cognitive-behavioral therapy helps patients cope with anxiety associated with their symptoms.[32] Multidisciplinary and interprofessional care is essential for effectively managing PPPD.

Consultations

An interprofessional approach is often recommended, involving primary care providers, nurses, pharmacists, neurologists, otolaryngologists, audiologists, and psychiatrists.[32]

Deterrence and Patient Education

PPPD can be a frustrating diagnosis for patients, families, and clinicians, as it affects their quality of life and currently lacks immediate treatment options. Patients need to understand that recovery takes time and often requires a multimodal approach. Recovery can include vestibular therapy, cognitive behavioral therapy, and the use of serotonin–norepinephrine reuptake inhibitors or selective serotonin reuptake inhibitors.[32] Promoting medication adherence and ensuring regular follow-up appointments are scheduled are essential.

Pearls and Other Issues

• PPPD is a chronic functional vestibular disorder. This condition was officially recognized by the World Health Organization in 2017 and is classified under code AB32.0 in the 11th edition of the International Classification of Diseases (ICD-11) within the Inner Ear section. PPPD is also referred to by other terms such as:

  • Chronic subjective dizziness
  • Visual vertigo
  • Phobic postural vertigo
  • Functional dizziness
  • Space and motion discomfort

• Key symptoms include persistent non-vertiginous dizziness or unsteadiness

  • Lasting 3 months or more
  • Present most days, often increasing throughout the day, but may wax and wane.
  • Momentary flares may occur spontaneously or with sudden movement

• Affected individuals feel worse when upright, exposed to moving or complex visual stimuli, and during active or passive head motion
• Typically occurs following occurrences of acute or episodic vestibular or balance-related problems
• Symptoms may begin intermittently and then consolidate
• Patients who experience a vestibular insult should be provided with vestibular therapy to reduce symptoms and decrease the likelihood of developing PPPD.
• Once PPPD is diagnosed, incorporating cognitive-behavioral therapy, as well as potentially prescribing an antidepressant or anxiolytic medication, can offer significant benefits.

Enhancing Healthcare Team Outcomes

Providing patient-centered care for individuals with PPPD requires a collaborative effort among healthcare professionals, including clinicians, advanced practice practitioners, nurses, pharmacists, audiologists, and other healthcare providers. The approach to PPPD should be multidisciplinary, involving management by a primary care provider and specialists in neurology, otolaryngology, and psychiatry. Patients often benefit greatly from vestibular balance rehabilitation therapy and cognitive-behavioral therapy. Psychiatry can also play a crucial role in helping patients learn to cope with their new fears and anxieties.[32]

Currently, no definitive physical examination, laboratory, or imaging findings exist for diagnosing PPPD. Healthcare professionals need to have the necessary clinical skills and expertise to diagnose, evaluate, and treat this condition. The diagnosis of PPPD should be considered for dizzy patients who have experienced a central, peripheral, or vascular insult that may have affected the vestibular pathway. Additionally, patients who have suffered from concussions or whiplash injuries should also be evaluated early for the development of PPPD.[21] Clinicians must have experience and proficiency in accurate history-taking, enabling patients to describe their symptoms, which may be the best way to infer that PPPD is a cause of those symptoms. Early intervention is crucial, and evidence suggests that addressing vestibular insults within the first eight weeks offers patients the best chance to prevent PPPD from becoming thoroughly intrusive into their daily lives.[31]

A strategic approach involving individualized care plans tailored to each patient's unique circumstances is essential. Ethical considerations arise when determining treatment options, respecting patient autonomy in decision-making, and ensuring quality of life. Responsibilities within the interprofessional team should be clearly defined, with each member contributing their specialized knowledge and skills to enhance patient care. Care coordination is crucial in ensuring seamless and efficient care for patients with PPPD, as the condition can be complex and may fluctuate in symptom intensity and duration. 

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Disclosure: Olivia Matz declares no relevant financial relationships with ineligible companies.

Disclosure: Carl Shermetaro declares no relevant financial relationships with ineligible companies.