Disequilibrium and gait disorders in older people

Disequilibrium is typically described as a feeling of dizziness when standing or walking that is not present while sitting or lying down. Since dizziness is such a common symptom in older people, the symptom may be dismissed as a normal aging phenomenon. On the other hand, the patient may be inappropriately given nonspecific treatment for dizziness such as meclizine or diazepam, which may worsen the condition, due to sedation. The frequency of dizziness as a presenting complaint increases with age; it is one of the most common complaints in patients over the age of 75. Because dizziness can represent many different abnormal sensations and because the diagnostic evaluation and treatment differ markedly depending on the type of dizziness, the initial task of the examining physician is to determine what the patient means by dizziness. The features of the three most common types of dizziness are summarized in Table 1.1 Falls are a well-known source of morbidity and mortality in older people with balance disorders.2,3 The risk of falls increases with age beyond the age of 60 and it is greater in women than in men. Most falls in older people result from an accidental slip or trip frequently associated with an unsteady gait.4 The cause of the disequilibrium can often be traced to decreased sensory input, slowing of motor responses and weakness of support. Medications, musculoskeletal limitations and deconditioning can also contribute to the problem.5 Falls can be directly traced to an acute attack of dizziness in less than 10% of patients.4 This low incidence probably can be attributed to the fact that most types of dizziness, including attacks of vertigo, begin slowly enough to allow the patient to sit down or to grab on to a support to avoid falling. To maintain postural stability when standing and walking, the brain must rapidly process signals from the visual, vestibular and somatosensory systems. Because balance depends on multiple sensory inputs, it can deteriorate when any of these systems fails individually or collectively. Agerelated changes have been identified in each of the special senses and in the cortical centres that integrate these signals. Changes in vestibular function with aging have been documented by numerous investigators.6,7 Degeneration of peripheral Disequilibrium and gait disorders in older people