Approach to a patient with dizziness

Vertigo is defined as “an hallucination of movement” and is the cardinal manifestation of a disordered vestibular system. Dizziness is a lay term meaning “a feeling of being in a whirl or in a daze or as if about to fall”, and is associated with a multiplicity of general medical disorders.

This semantic distinction is rarely volunteered by the older patient, who more often complains of feeling faint, swimmy or light-headed. Therefore all complaints of disorientation are best considered within a single diagnostic approach.

Dizziness in older people is usually multifactorial — the result of central pathology and/or multiple sensory deficits (uncorrectable visual impairment, neuropathy, vestibular deficits, cervical spondylosis, orthopaedic disorders interfering with joint mechanoreceptors) rather than vestibular degeneration alone. Vestibular degenerative change tends to occur symmetrically, and symptoms arise from asymmetry of afferent input.

Do not attribute vertigo to ‘age’. A thorough history and examination will often give a clear direction as to diagnosis, and correct diagnosis allows treatment of many peripheral and central vestibular disorders.

The three key axes are the character, time course and associated symptoms of the dizziness.

Character: peripheral labyrinthine disease classically gives acute, unprecipitated, short-lived attacks of rotational disequilibrium with nausea and vomiting (rarely diarrhoea); central vestibular disease gives a more insidious, protracted sense of instability.

Exceptions to remember: short-lived attacks may also occur in epilepsy and vertebrobasilar artery ischaemia; protracted instability may also occur with uncompensated peripheral vestibular disorders, bilateral vestibular failure and psychogenic disequilibrium.

Other typical vestibular symptoms are a sensation of being pulled downward or sideways, of the room tilting, and of swimming, floating and light-headedness. A clear description of subjective or objective motion raises suspicion of vestibular pathology, whereas light-headedness, swimminess or faintness suggests a general medical or neurological disorder.

Always take a full drug history (ototoxic and vestibulotoxic drugs, antihypertensives, sedatives), and ask about hearing loss, tinnitus and aural fullness, headache, and relationship to posture, head position, meals, cough or micturition.

General medical — haematological: anaemia, polycythaemia, hyperviscosity syndromes.

General medical — cardiovascular: postural hypotension, carotid sinus syndrome, dysrhythmias, mechanical dysfunction, shock.

General medical — metabolic/endocrine: hypo- and hyperglycaemia, thyroid disease, chronic renal failure, alcohol.

Neurological — supratentorial: trauma, neoplasia, epilepsy, cerebrovascular disease, syncope, psychogenic.

Neurological — infratentorial: vertebrobasilar insufficiency, subclavian steal, Wallenberg’s syndrome, anterior inferior cerebellar artery syndrome, degenerative disorders including neuropathy, tumours including those of the vestibulocochlear nerve, infective disorders (Ramsay-Hunt, neurosyphilis, tuberculosis), foramen magnum abnormalities, cerebellar degeneration, basal ganglion disease, demyelinating disease.

Otological: drug-induced/ototoxic, degenerative (BPPV), post-traumatic syndrome, infection, vascular, tumours, Menière’s disease, otosclerosis and Paget’s disease, autoimmune disorders.

Others: migraine and multisensory dizziness syndrome.

Otological examination, with audiological testing where symptoms suggest vertigo — this helps differentiate inner ear from central nervous system involvement.

Vestibulo-ocular assessment: look for spontaneous nystagmus; perform the head thrust (head impulse) test — on a rapid head thrust to one side the eyes move with the head and lose the target, and corrective saccades are then required to bring the visual focus back, indicating vestibular hypofunction on that side.

The presence of positional nystagmus is a most valuable and most frequently overlooked sign and should be sought by a briskly performed Dix-Hallpike manoeuvre in every dizzy older patient.

Vestibulospinal assessment: Romberg and postural sway; note that older patients with unilateral vestibular hypofunction show markedly increased postural sway compared with younger patients with the same disorder. Gait testing — ask the patient to walk toward a fixed point with eyes closed; a tendency to veer to one side usually indicates an ipsilateral peripheral vestibular disturbance but may occasionally be cerebellar. Broad-based ataxic gait suggests cerebellar disease.

Anxious older patients tend to fall backward “like a wooden soldier”, which indicates a non-organic component — but this is almost always seen in the presence of an underlying abnormality that will be identified on full examination.

Screening in the CGA: ask “Do you get dizzy, or does your head spin around?” If yes, check for postural hypotension, perform the Dix-Hallpike manoeuvre for BPPV, check haemoglobin, and apply the Geriatric Depression Scale.