INSTABILITY AND FALLS

Unstable gait and falls are a common source of concern for the older adult population. The literature reveals that 30% of community-dwelling individuals older than 65 years of age and 50% of nursing home residents fall each year. Most falls do not result in serious injury, but the potential for serious complications and even death is real. Accidents are the seventh leading cause of death among older adults, with falls ranking first in this category. Hip fractures are one of the most feared complications from a fall. More than 340,000 individuals fracture a hip each year; most of these are elderly women. Significant morbidity occurs as a result of a hip fracture. The literature varies, but as many as 50% of older adults who sustain a hip fracture are re­ported to require nursing home care for at least 1 year, and up to 20% die in the year after a hip fracture. Other bones frequently fractured by older adults who fall are the humerus, wrist, and pelvis. These bones bear the brunt of osteoporotic changes and, as a result, are more vulnerable to injury. Soft tissue injuries such as sprains and strains also can result from falls.^46–48

An individual's activity may be restricted because of fear on the individual's or caregiver's part about possible falling. These anxieties may lead to unnecessary restric

tions in independence and mobility and commonly are mentioned as a reason for institutionalization.

Although some falls have a single, obvious cause, such as a slip on a wet or icy surface, most are the result of sev­eral factors. Risk factors that predispose to falling include a combination of age-related biopsychosocial changes, chronic illnesses, and situational and environmental haz­ards. Gait and stability require the integration of informa­tion from the special senses, the nervous system, and the musculoskeletal system. Changes in gait and posture that occur in healthy aged individuals also contribute to the problem of falls. The older person's stride shortens; the el­bows, trunk, and knees become more flexed; toe and heel lift decrease while walking; and sway while standing in­creases. Muscle strength and postural control of balance decrease, proprioception input diminishes, and righting reflexes slow. All these factors predispose the older adult to the possibility of falling.⁴⁹

Because the central nervous system integrates sensory input and sends signals to the effector components of the musculoskeletal system, any alteration in neural function can predispose to falls. For this reason, falls have been as­sociated with strokes, Parkinson's disease, and normal-pressure hydrocephalus. Similarly, diseases or disabilities that affect the musculoskeletal system, such as arthritis, muscle weakness, or foot deformities, are associated with an increase in the incidence of falls. Age- and disease-related alterations in vision and hearing impair sensory input and can contribute to falls. Vestibular system alterations such as benign positional vertigo or Ménière's disease cause

balance problems that can result in falls. Cognitive impair­ments such as dementia have been associated with an in­creased risk for falling, most likely because of impaired judgment and problem-solving abilities.

Input from the cardiovascular and respiratory systems influences function and ambulation. Cardiovascular dis­eases, especially postural hypotension, can cause recurrent falls, solely or in association with the previously men­tioned factors. The dramatic drop in blood pressure on ris­ing that is seen in postural hypotension can cause falls because of syncope and dizziness.

Medications are an important and potentially cor­rectable cause of instability and falls. Centrally acting medications, such as sedatives and hypnotics, have been associated with an increase in the risk for falling and injury. Diuretics can cause volume depletion, electrolyte distur­bances, and fatigue, predisposing to falls. Antihypertensive drugs can cause fatigue, orthostatic hypotension, and im­paired alertness, contributing to the risk for falls.

Environmental hazards play a significant role in falling. More than 70% of falls occur in the home and often involve objects that are tripped over, such as cords, scatter rugs, and small items left on the floor. Poor lighting, ill-fitting shoes, surfaces with glare, and improper use of ambulatory devices such as canes or walkers also contribute to the problem.^47,48 Table 3-2 summarizes the possible causes of falls.

Preventing falls is the key to controlling the potential complications that can result. Because multiple factors usu­ally contribute to falling, the aim of the clinical evaluation is to identify risk factors that can be modified. Assessment

of sensory, neurologic, and musculoskeletal systems; direct observation of gait and balance; and a careful medication inventory can help identify possible causes. Dizziness, either transient due to a self-limiting illness or recurring, is a risk factor for falls. In one study, 24% of persons older than 72 years of age reported at least once-monthly epi­sodes of dizziness.⁵⁰ Dizziness was associated with several conditions, including cardiovascular disorders, sensory im­pairment, balance disturbances, and psychological condi­tions. The number of medications the person took also was associated with episodes of dizziness.⁵⁰

Preventive measures can include a variety of interven­tions, such as surgery for cataracts or cerumen removal for hearing impairment related to excessive earwax accumula­tion. Other interventions may include podiatric care, dis­continuation or alteration of the medication regimen, exercise programs, physical therapy, and appropriate adap­tive devices. The home also should be assessed by an appro­priate health care professional (e.g., occupational therapist) and recommendations made regarding modifications to promote safety. Simple changes such as removing scatter rugs, improving the lighting, and installing grab bars in the bathtub can help prevent falling. These interventions can maximize the older adult's independence and prevent the morbidity and mortality that can occur as a result of a fall.

 

Risk Factors for Falls

Category of Risk Factors

Accidents and environmental hazards Age-related functional changes

Cardiovascular disorders

Gastrointestinal disorders Genitourinary disorders Medication use

Metabolic disorders Musculoskeletal disorders Neurologic disorders

Prolonged bed rest Respiratory disorders Sensory impairments

Examples

Slips, trips

Clutter, cords, throw rugs

Decreased muscle strength, slowed reaction time, decreased proprioception, im­paired righting reflexes, increased postural sway, altered gait, impaired visual and hearing function

Aortic stenosis, cardiac dysrhythmias, autonomic nervous system dysfunction, hypovolemia, orthostatic hypotension, carotid sinus syncope, vertebrobasilar insufficiency

Diarrhea, postprandial syncope, vasovagal response

Urinary incontinence, urinary urgency/frequency, nocturia

Alcohol, antihypertensives, cardiac medications, diuretics, narcotics, oral hypogly-cemic agents, psychotropic medications, drug-drug interactions, polypharmacy

Anemia, dehydration, electrolyte imbalance, hypothyroidism

Osteoarthritis, rheumatoid arthritis, myopathy

Balance/gait disorders, cerebellar dysfunction, stroke with residual effects, cervical spondylosis, central nervous system lesions, delirium, dementia, normal-pressure hydrocephalus, peripheral neuropathy, Parkinson's disease, seizure disorders, transient ischemic attack

Hypovolemia, muscle weakness from disuse and deconditioning

Hypoxia, pneumonia

Decreased visual acuity, cataract, glaucoma, macular degeneration, hearing impairment, vestibular disorders