Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
Older Adults With Dizziness: Rehabilitation Strategies and Novel Interventions
Introduction
Dizziness is a common problem in the elderly (65 years and older), with a prevalence between 13% and 38% depending on the population studied. Dizziness affects the lives of older adults and is associated with restrictions in activities of daily living, worsening of cognitive status, fear of falling, and an increased risk of falling. Dizziness and its relationship to falls are of particular concern because falls pose a serious threat for older adults. Of older adults who fall, 10% sustain a major injury, including head injury, hip fractures, or dislocation. Of those who fracture their hip, 20% die within 1 year. Such consequences not only suggest the disabling nature of dizziness and imbalance but also demonstrate the detrimental repercussions of dizziness in older adults.
Dizziness is an imprecise term used by patients to describe symptoms of vertigo, syncope, lightheadedness, disequilibrium, and other non-specific sensations. Each of these terms is defined and linked to a host of diagnoses listed in Table 19.1 . Dizziness may stem from central disorders and/or peripheral vestibular disorders. Central disorders that give rise to dizziness include cerebrovascular disease/vertebrobasilar insufficiency, multiple sclerosis (MS), Parkinson disease (PD), tumors, normal-pressure hydrocephalus, and global atrophy. Although central disorders appear in only 8% of patients with dizziness, they are strong predictors of falls, with more than 50% of patients with central disorders falling more than twice a year. Of patients with central disorders and history of frequent falls, 12%–42% sustain head injury or hip fracture.
TABLE 19.1
Dizziness Terms, Description of Symptoms, and Common Diseases Associated With Each Description a
| Symptom | Description of Symptom | Associated Pathologies |
|---|---|---|
| Vertigo | Illusion of movement of the body or spinning of the environment Cause: peripheral or central vestibular disorder |
|
| Syncope | Loss of consciousness that is not associated with illusion of movement Cause: vascular disorder |
|
| Disequilibrium | Sensation of imbalance without illusion of movement or loss of consciousness Cause: visual/somatosensory impairment |
|
| Other nonspecific forms | Vague floating sensation that does not follow the description of any other form. Cause: not particular to a specific system |
|
a People with complete bilateral vestibular lesion do not complain of dizziness. Their chief complaint is “oscillopsia,” which is often described as visual jumping or environment moving.
Dizziness may also stem from peripheral vestibular disorders. In contrast to central disorders, peripheral disorders are considered the principle cause of dizziness, appearing in 40%–50% of patients with dizziness. Peripheral vestibular disorders constitute a host of diagnoses ( Table 19.1 ), with benign paroxysmal positional vertigo (BPPV) being the most common. Peripheral disorders result in recurrent falls in approximately 25% of patients, and up to 10% of these patients sustain serious injuries.
It is worth noting that dizziness can stem from a combination of peripheral and central disorders in 20%–40% of patients. In addition, dizziness may occur from causes unrelated to the vestibular system, such as cardiovascular disorders, medication and polypharmacy, age-related structural deterioration of the vestibular system, and psychogenic disorders.
Many types of dizziness, when assessed appropriately, can be managed with vestibular rehabilitation exercises (VREs). VREs may be blended with novel technologies such as virtual reality or the Nintendo Wii system. VREs have been shown to improve dizziness, quality of life, and postural control and reduce the risk of falling.
In the next sections, the role of rehabilitation providers in screening, assessing risk of falling, assessing quality of life, and managing patients with dizziness is illustrated. Also, VREs and theories related to functional recovery of certain conditions of dizziness are discussed. In addition, novel rehabilitation technologies for older adults with dizziness are described.
The Role of the Rehabilitation Provider in Evaluating Patients With Dizziness
The evaluation of older adults with dizziness by rehabilitation providers generally includes screening, assessment of fall risk, and assessment of quality of life.
Screening
Because dizziness stems from many causes, rehabilitation providers need to work with physicians and other healthcare providers to determine the cause and recommend the optimal treatment strategy. To do that, rehabilitation providers can screen patients with dizziness using a classification system that places the patients into three groups: red flags, yellow flags, and green flags. Red flag screening involves assessing patients with dizziness for signs, symptoms, or symptom behavior indicative of serious pathologies ( Table 19.2 ). Yellow flag screening involves assessing patients for the presence of behavioral or nonbehavioral disorders. Behavioral disorders that may be associated with dizziness include panic disorders, phobic disorders, and depression. Nonbehavioral disorders include PD, stroke, head injuries, MS, migraine (not common among older adults with dizziness), and musculoskeletal disorders. Green flags indicate patients whose dizziness stems from primarily peripheral vestibular disorders, and the assessment involves determining whether the patient has BPPV, unilateral vestibular hypofunction, or bilateral vestibular loss.
TABLE 19.2
Symptoms, Symptom Behavior, and Signs that Indicate Serious Pathology (Red Flags)
Symptoms in patients with dizziness that may indicate the presence of serious pathology
Symptom behavior in patients with dizziness that may indicate the presence of serious pathology
Signs in patients with dizziness that may indicate the presence of serious pathology
|
Patients with red flags are not appropriate for vestibular rehabilitation unless a physician has already cleared them. These signs and symptoms when found during the clinical examination indicate that the patient should be referred to other healthcare providers.
a Symptoms that occur in the period between the triggering factor and the onset of dizziness and include lightheadedness, pallor, salivation, blurred vision, or increased heart rate.
This screening process of dizziness can aid the rehabilitation provider and the physician in determining the best management strategy. For red flags, patients are less likely to benefit from VREs; these patients require specialized, often urgent medical attention that could involve medication or surgery. For yellow flags, patients may benefit from VREs; however, the effect of VREs may be lessened or delayed because of the presence of concomitant disorders, vestibular/ocular motor impairment, or catastrophic emotional reaction to dizziness. As such, the concomitant disorders or impairments should be treated as the patient is receiving VREs, which would likely improve the results of VREs. For green flags, patients are more likely to benefit from VREs, and as such, rehabilitation providers may treat these patients independently. If an acute vestibular hypofunction is identified (within 4 weeks), a medical referral for consideration of steroids is advised.
Assessment of Falling Risk and Quality of Life in Older Adults
The rehabilitation provider uses a multidimensional assessment of fall risk and quality of life. The assessment starts with history taking to identify frequent fallers (i.e., more than twice a year), use of medication(s) associated with increased fall risk, fear of falling, and functional limitations in daily living activities. The assessment continues by identifying physical factors related to falls, such as visual acuity, cognitive status, need for an assistive device, balance, orthostatic vital signs, sensation, and fallers’ vital signs. Fallers’ vital signs include gait speed, gait variability, the stop walking when talking test, and the Timed Up and Go (TUG) test.
Similar to measuring blood pressure and body temperature to screen for general health status, gait speed can also be used to assess general health status and disability in older adults. Age-appropriate gait speed is reflective of health status because gait requires body support, muscle power, coordination, and timing. Thus the interaction of these factors to produce an adequate gait speed can be viewed as a proxy for effective interaction of the musculoskeletal, nervous, and cardiopulmonary systems.
When testing gait speed, it is important to specifically attend to gait fluctuations during slow walking; such fluctuations are predictive of falls. Also, it is important to observe whether a patient stops walking when talking because such behavior is linked to fall-related anxiety. Gait speed is a suitable measure to assess fall risk and quality of life because it provides quick, inexpensive, and reliable information regarding quality of life and risk of falling. Therefore improvement in gait speed has been shown to be a good indicator of treatment effectiveness, and slowing of gait speed can indicate a worsening medical condition.
The TUG test is often used to assess a person’s ability to rise from a chair, ambulate, and turn, which can be difficult for individuals with central and/or peripheral vestibular disorders. The time (in seconds) required to perform the test is strongly correlated with functional mobility. People who can complete the TUG within 20 seconds are found to be independent in transfer tasks such as moving from the wheelchair to a bed, and have sufficient gait speed (0.5 meters/second) for limited community mobility. Podsiadlo and Richardson reported that people who walk very slowly (0.5 meters/second) were not able to ambulate freely in the community. Older adults who took 13.5 seconds or longer to perform the TUG test were classified as frequent fallers, with an overall correct prediction rate of 90%. Also, people who required more than 13.5 seconds to perform the TUG were 3.7 times more likely to have reported a fall in the previous 6 months. The sensitivity of the TUG test for fall prediction in persons with vestibular disorders is 80%, and the specificity is 56% for those who score greater than 11.1 seconds on the test. Generally, slow completion of the TUG test is associated with an increased impairment of function and warrants referral for rehabilitation, particularly if symptoms listed in Table 19.3 are present.
TABLE 19.3
Older Adults Should Be Referred to Rehabilitation If They Have One or More of the Following Signs
| Positive Dix-Hallpike test Positive Romberg test Dizziness with movement of the head Dizziness associated with neck pain Slow gait History of falling two or more times within the past 6 months Inability to rise from a chair without using arm support Fear of falling that prohibits the person from participating in activities of interest Arrhythmic gait |
The Role of the Rehabilitation Provider in Treating Patients With Dizziness
Dysfunction in the vestibular system can result in dizziness, postural imbalance, increased risk of falling, and ultimately a lower quality of life. To rehabilitate the vestibular system, VREs are commonly recommended ( Table 19.4 ). Currently, VREs are utilized by various practitioners but mainly physical therapists specializing in vestibular physical therapy.
TABLE 19.4
Exercises Commonly Used in Vestibular Physical Therapy Management
| Type of the Exercise | Reason for the Exercise | Description |
|---|---|---|
| Vestibulo-ocular reflex (VOR) adaptation exercises | Help the central nervous system to adapt to a change or loss in the vestibular system input | VOR × 1: The patient moves the head to both sides (yawing or pitching) while keeping his eyes fixed on a stationary target ( Fig. 19.1 ) VOR × 2: The head and the hand holding the target are moving in opposite directions with the eyes fixated on the target |
| Habituation exercises | Involves repeated exposure to a provoking stimulus or movement so the pathologic response to the stimulus is reduced | The therapist selects movements that provoke the patient’s symptoms, and the patient repeats these motions until the patient no longer reacts adversely to the stimuli |
| Substitution exercises | Help patients improve one channel of sensory input (vision, somatosensory, proprioception) by blocking sensory inputs from the other two channels | To challenge proprioception, the patient closes the eyes and tries to maintain balance while standing |
| Optokinetic stimulation | Can help to desensitize people who are very sensitive to motion in the periphery and also who are motion sensitive | Example: Have the patient sitting and spin an umbrella about 1 m away from them in a circle while they look at the center of the umbrella |
Improvements in a variety of areas after VREs have been reported regardless of patient age. VREs were found to be effective in patients with vestibular disorders (even with a history of symptoms lasting over 20 years), patients with PD, patients with anxiety and depression, and in postsurgical patients, such as after removal of an acoustic neuroma.
After VREs, patients show dramatic improvements in their perception of dizziness, ability to perform activities of daily living, emotional status, and improved static and dynamic balance. Positive effects of VREs are reported to occur as early as 3 weeks after initiation of therapy; for those who do not receive VREs, improvement may take as long as 3 months. This suggests that VREs expedite improvement.
The effect of VREs on gait and balance may be significantly enhanced if the performance of VREs is closely monitored ; if VREs are combined with flexibility, cognition, sensory interaction, and muscle strength exercises ; or if VREs are combined with canalith repositioning maneuvers when appropriate. Combining VREs with other interventions might be preferred when a patient has a concomitant disorder or a poorer baseline status; this combination can be achieved without increasing the number of treatment visits.
The Effect of Vestibular Rehabilitation on Various Conditions
Table 19.5 summarizes conditions that improve with vestibular rehabilitation and positive outcomes that were found with each condition. Theories that underlie why vestibular rehabilitation may be effective are described in Table 19.6 .
TABLE 19.5
Conditions That Improve With Vestibular Rehabilitation
| Patient Diagnosis | Noted Improvement With Vestibular Physical Therapy |
|---|---|
| Benign paroxysmal positional vertigo | Subjective report of vertigo, nystagmus, quality of life |
| Unilateral vestibular disorders | Fall risk, vision, balance, quality of life |
| Chronic peripheral vestibular dysfunction | Vestibulo-ocular reflex gain and dizziness, standing balance, emotional status (i.e., anxiety) |
| Bilateral vestibular dysfunction | Postural control, gait speed, dizziness, vision |
| Vestibular neuritis | Ocular torsion (i.e., nystagmus), postural control, ambulation skills and gait |
| Post-acoustic neuroma resection | Postural control, dizziness, motion sensitivity |
| Meniere’s disease | Self-report of symptoms, balance, dizziness, motion sensitivity |
| Anxiety associated with vestibular disorder | Anxiety, subjective report, postural control, presence of nystagmus, and ability to cope with dizziness |
| Cervical vertigo | Postural stability, decreased neck pain, intensity of dizziness, postural sway |
| Head injury | Gait improved, postural stability, less dizziness, gaze stability |
| Cerebellar disease and dysfunction | Self-perception of symptoms, postural control, gait, decreased risk of falling |
| Multiple sclerosis | Subjective report of dizziness and postural control |
| Parkinson’s disease | Subjective complaint of vertigo |
TABLE 19.6
Theories Underlying Vestibular Rehabilitation
| Theory | Brief Description | Function | Malfunction | Exercises |
|---|---|---|---|---|
| Vestibulo-ocular reflex (VOR) adaptation | A reflex mediated by a three-neuron arc:
|
Enables stabilization of a visual image on the retina during head movement Produces an eye movement of equal velocity to head movement but in the opposite direction. When the head moves to the right, the eyes instantaneously move to the left at the same speed of the head. This ratio of eye movement velocity opposite to head movement velocity is referred to as VOR gain |
The eyes are not moving in the opposite direction of the head with the same speed as the head. The image stabilization on the retina during head movement is affected resulting in corrective eye movements | VOR × 1 and VOR × 2 ( Fig. 19.1 ). It is believed that these exercises decrease symptoms of dizziness and improve function in elderly patients with vestibular hypofunction |
| Cervicoocular reflex (COR) | Eye movement induced by neck stimulation during trunk rotation while the head is stationary | Interacts with the VOR to drive eye movement based on input from cervical proprioceptors | The COR may be adaptable in some but not all people with vestibular hypofunction. This response is called for when needed, although not all patients have the ability to utilize the COR | Body moving with the head stable |
| Vestibulo-spinal reflex (VSR) | Input regarding body position is sent from semicircular canals and vestibular nuclei to medial and lateral vestibulospinal tracts | Stabilize the body via increasing extensor muscle activity on the side to which the head is turned with concomitant flexion activity on the other side | Inability to maintain balance | Balance training and gait exercises |
| Sensory reweighting | Sensory reweighting consists of:
|
There are three sensory modalities through which the body maintains balance or controls posture | When somatosensation, vision, or vestibular function is lost or impaired, the central nervous system readjusts to become more reliant on the remaining intact modalities | During vestibular rehabilitation the patient is repeatedly exposed to various sensory information so the brain can optimize postural responses to maintain balance |
Peripheral Vestibular Disorders
Benign paroxysmal positional vertigo
Even though dizziness is very common among older adults, it seems that BPPV is underestimated in this population , possibly because the majority of older adults (61%) do not report dizziness unless they are asked. This is concerning because older adults with BPPV have a higher prevalence of falls compared to those without BPPV. These findings suggest that older adults should be screened for dizziness even if they do not report it as a symptom.
Clinically, BPPV can be easily identified by provoking symptoms using the Dix-Hallpike test (see Chapter 9 ). If BPPV is noted, patient referral to clinicians who are trained in canalith repositioning procedures (CRPs) is warranted. Based on strong evidence, CRPs are reported to be very effective in treating symptoms of BPPV and improving the perception of verticality. Shepard and Telian reported complete resolution of symptoms in 100% of their population after performing CRPs. If CRPs do not resolve patients’ symptoms, it is likely that another type of VRE would improve symptoms; a combination of the CRPs and VREs may also improve outcomes.
Special consideration must be taken into account when testing or treating older adults with BPPV. Because skilled or self-administered repositioning maneuvers typically require approximately 30 degrees of neck extension and 45 degrees of neck rotation, patients with spine conditions must be addressed cautiously. Patients with neck or low back pain should have cervical or lumbar support during CRP because limited neck or trunk mobility can be affected by quick and unanticipated movements, which might reproduce the patient’s pain. Patients with osteoporosis or Paget’s disease are at risk for pathologic fractures. Most importantly, patients with severe rheumatoid arthritis must be treated with great care because ligamentous laxity, especially within the upper cervical spine, is very common, and moving the neck beyond normal limits may cause serious injury or a lesion to the spinal cord. Thus it is important to screen patients with BPPV for these conditions before beginning testing or intervening.
Chronic unilateral vestibular dysfunction
Patients with chronic unilateral vestibular dysfunction are good candidates for VREs and have a good prognosis. Ninety percent of patients dramatically improve or completely recover postural control and disability status after rehabilitation, provided that the patient has no central disorders. Improvements in these patients were reported in dizziness symptoms, postural control, as well as physical and emotional status after VREs.
Improvements after VREs are correlated with plasticity and compensation mechanisms in the central nervous system (CNS). This correlation between VREs and plasticity is expressed as changes in the vestibulo-ocular reflex (VOR), enhanced balance and reduced “retinal slip” or apparent motion of visual images. Improvements in dizziness, postural control, and quality of life have been reported in patients with chronic vestibular disorders after receiving a combination of VREs and visual stimuli by digital images. Based on strong evidence, using VREs for patients with unilateral or bilateral vestibular hypofunction is suggested in a recent practice guideline.
You're Reading a Preview
Become a Clinical Tree membership for Full access and enjoy Unlimited articles
If you are a member. Log in here