What causes age-related dizziness and imbalance?

The brain receives and processes information from the inner ear balance sensors (vestibular system), the eyes (visual system), and sensors in the muscles and joints (proprioceptive system) to keep the body balanced while standing or walking. Signals are also sent to control eye movements to keep vision stable while moving. A breakdown or information mismatch within any part of the balance system can result in dizziness or imbalance. As part of the normal aging process, every part of the delicate and complex balance system gradually becomes impaired with age.

The most common vestibular (inner ear balance) disorders in older people include:

Benign positional paroxysmal vertigo (BPPV)
With increasing age, the crystals (otoconia) in the inner ear become less dense and more varied in size. They are also replaced more slowly. These changes lead to a greater likelihood of BPPV. This condition is the most common vestibular disorder in the elderly. By age 70, one third of people will have had BPPV at least once. People with osteoporosis are up to 3 times as likely to have BPPV. Older people may not specifically complain of vertigo (spinning sensation) when they have BPPV.

Bilateral vestibulopathy
Bilateral vestibulopathy means the loss of function on both sides of the balance part of the inner ear (vestibular system). It is often overlooked as a cause of dizziness and unstable gait in older people.

Symptoms include staggering while walking, particularly in the dark and on uneven ground. Some people also have blurred or “jumpy” vision (oscillopsia). The symptoms are most obvious when vision is limited (such as in the dark or when the eyes are closed) or when walking slowly.

Causes include medications that are toxic to the vestibular system (vestibular toxins) and pre-existing bilateral (in both ears) Ménière's disease. In older people, bilateral vestibular loss is sometimes associated with peripheral neuropathy. In about 50% of cases, no specific cause can be identified.

Vestibular neuritis
Vestibular neuritis is a condition that causes a sudden, severe attack of dizziness, usually with nausea and vomiting. This attack may last for days. Vestibular neuritis does not come and go. It is a single, major event. But after the attack, people may still have balance problems and unsteadiness for weeks or months. The aged-related degeneration of multiple systems makes it more difficult for older people to recover from vestibular neuritis.

Vestibular migraine is uncommon in older people.

Other causes and risk factors for age-related dizziness and imbalance include:

• Combination of disorders
  Often, age-related dizziness and imbalance are caused by a combination of conditions (comorbidities) affecting the muscles, joints, and nerves as well as impaired brain functioning and vision. Having 3 or more conditions increases risk.
• Medication
  One or more side effects of many prescription and over-the-counter medications can affect balance. Taking 4 or more medications increases risk.
  Common problems include vision changes, light-headedness, drowsiness, and impaired judgement.
  Medications often associated with dizziness in older people include:
  • anticonvulsants
  • antidepressants
  • antianxiety medications (anxiolytics)
  • sedatives, including hypnotics
  • strong pain relievers (analgesics)
  • muscle relaxants
  • medications to prevent and treat abnormal heartbeats (antiarrhythmics)
  • chemotherapy
• Gait instability
  Walking speed decreases with age. After 60, it goes down by about 1% each year. Walking slowly is associated with a greater risk of falling.
  An unsteady way of walking (gait) is associated with how well an older person’s sensory system, mental processes (cognition), and ability to move (locomotion) are working. Not being able to walk and talk at the same time is a sign of decline. Older people with dementia fall more often than cognitively healthy people of the same age.
• Fear of falling
  Fear of falling is a major concern of many older people with unsteady gait. It can lead to a downward spiral as decreased confidence leads to inactivity, physical deterioration, and a greater likelihood of falling.
• Loss of muscle mass
  Loss of muscles mass, especially in the core and legs, starts after age 50. Up to one-third of former muscle mass may be lost. The loss affects leg strength and power. Common causes include lack of exercise and physical activity, disorders such as arthritis as well as stiffening and aching of the joints (polymyalgia rheumatica or PMR). Loss of muscle mass is a major risk factor for gait disorders and falls. These issues all increase the risk of falling. Another name for loss of muscle mass is sarcopenia (saar-kow-PEE-nee-uh).
• Vision issues
  Vision issues often associated with aging include:
  • taking longer for eyes to adjust to darker or brighter areas
  • decreased depth perception
  • unsteadiness caused by changes in eyeglass prescriptions or adjusting to multi-focal lenses
  • cataracts
  • macular degeneration
• Dehydration
  Poor hydration is more likely with age. The part of the brain that tells us we are thirsty becomes less active over the age of 65. Even mild dehydration can cause light-headedness. Dehydration, particularly in warm weather or with increased activity, can result. In addition, older adults are more likely to:
  • have impaired kidney function
  • avoid fluids because of poor bladder control (incontinence)
  • take medication that increases urination
  • have mobility issues that make it more challenging to get to the bathroom.

• Blood pressure abnormalities
  These include high blood pressure (hypertension), low blood pressure (hypotension), and dropping blood pressure when getting up from lying or sitting (postural hypotension). All 3 may cause dizziness and increase the risk of falling.
• Cognitive (thinking) issues
  These include memory problems and confusion or difficulties with thinking or problem solving. Judgement can be affected and risk of falling increased.
• Bladder or bowel conditions
  Incontinence or urgency may result in rushing to the toilet many times both day and night. This, combined with unsteadiness on the feet, can increase the risk of falling.
• Foot problems
  These include numbness, corns, calluses, bunions, ingrown or thick nails, and ulcerations. Foot problems can make it more challenging to keep physically active, leading to increased risk of falling.
• Drinking alcohol
  It is harder for aging bodies to process alcohol, especially when combined with medication. Greater sensitivity to its effects is linked to increased risk of falling.
• Central vertigo
  Central vertigo is dizziness due to a central nervous system (brain and spinal cord) disorder. It develops because of damage along the vestibular structures and pathways. An abrupt blockage of blood vessels leading to the brain may result in sudden dizziness and/or imbalance. This may be due to a labyrinthine infarction (a blockage in the inner ear) or an ischaemic stroke in the brain. Dizziness and an unstable gait is often a first symptom of degenerative diseases like Parkinson’s, cerebellar disorders (also called ataxias), and dementia (including normal-pressure hydrocephalus, Alzheimer’s disease, and white matter disease).
• Cardiovascular disease
  Problems with heart rate or rhythm, as well as having had a heart attack in the past, can cause dizziness and problems with balance.
• Cervical spondylosis
  This is a type of osteoarthritis that causes deterioration in the vertebrae, discs and ligaments in the neck or cervical spine. Sometimes these changes can affect blood supply to the brain, possibly causing dizziness and even blackouts.