2.1 Risk factors and evaluation

With advancing age, the normal adult gait changes to a hesitant, broad-based, small stepped gait, often with a stooped posture, diminished arm swing and en bloc turns [4]. Disturbances of gait not only indicate the risk of falls but may herald or reflect serious underlying ill health [5]. The pattern of shortened step length and slowing of gait is particularly noticeable in individuals who have fallen repeatedly and is sometimes called the “post-fall syndrome”, which is related to fear of further falling [6].

Since falls in older adults are usually the result of multiple conditions and circumstances, falls are classified as a geriatric syndrome rather than a discrete disease. The ability to transfer and walk safely depends on coordination among sensory (eg, vision, vestibular, proprioception), central and peripheral nervous, cardiopulmonary, musculoskeletal, and other systems. Falls that occur during usual daily activities generally result from impairments in one or more systems, such as occurs in frailty [7].

Common risk factors for falls include previous falls, age > 75 years, cognitive and visual impairment, arthritis, depression, and the use of four or more medications (ie, polypharmacy), particularly antihypertensive and psychiatric medications. The risk increases with increasing number of factors, from 8% with no risk factors to 78% among those with four or more risk factors [8].

A more comprehensive list of risk factors can be found in Table 1.11-1 .

All patients should be asked about a history of falls, the specific circumstances of the falls, and any associated injury. Focused questions regarding dizziness, lightheadedness, weight loss, symptoms of neuropathy, gait instability and medication changes are necessary for adequate assessment for previous and future falls. Checking vision, postural blood pressure and a general neurological exam are appropriate for most patients who report falls [10].

Osteoporosis is an important consideration when assessing someone at risk for falls and fractures. This population is at greater risk of serious injuries related to falls; diagnostic tools like the Fracture Risk Assessment (FRAX) of the World Health Organization, as well as radiographic tools like bone densitometry using dual-energy x-ray absorptiometry or calcaneal quantitative ultrasound are useful methods to assess osteoporosis and fracture risk. If osteoporosis is diagnosed, management should be instituted including pharmacological and nonpharmacological interventions. Osteoporosis is further described in chapter 1.10 Osteoporosis.

2.2 Balance and gait evaluation

There are simple office-based assessments that can help evaluate gait and predict falls. The Timed Up and Go (TUG) test is the most frequently recommended screening test for mobility and entails having the patient get up from a chair, walk 3 meters (about 10 feet), turn and return to the chair, and sit down [11]. Any abnormality in movement suggests balance or gait impairment and increased risk of falling, requiring further assessment and suggest a likely need for treatment. Clear TUG completion times that indicate increased fall risk have not been definitively established, although cut points at 12 and 13.5 seconds have been suggested [12, 13].

The more detailed performance-oriented mobility assessment (POMA) involves assessing the quality of transfer, balance, and gait maneuvers used during daily activities and takes about 5–10 minutes to complete [14]. The POMA is not appropriate for highly functional patients or patients with a single disabling condition. It includes observing transfer and balance maneuvers such as getting up from a chair, performing side-by-side 1-leg and tandem stands (5–10 seconds each), turning in circle, and sitting down. In addition to the evaluation of gait during a 3-meter walk, gait initiation, heel-toe sequencing, step length, height, symmetry, path deviation, walk stance, steadiness on turning, arm swing, as well as neck, trunk, hip, and knee flexion are also assessed. These results can not only assess the risk of falling but also determine if there are balance and gait impairments that need intervention as well as assess the presence of neurological, musculoskeletal or other relevant disorders.

2.3 Prevention strategies

Trials of fall prevention strategies have shown that approximately 30% of falls can be prevented. Of those, several healthcare-based strategies have been shown to reduce the rate of falling; however, their implementation may be problematic, as clinicians tend to be more experienced at managing discrete diseases than at managing multifactorial conditions [15, 16].

Key domains of fall prevention typically include physical strengthening, medical evaluation and treatment, medication adjustment, environmental modification and education [10]. Key strategies for most patients include the following:

• 
  

  Review and modify risk factors related to the patient′s falls. Modifiable risk factors include correcting vision, reducing environmental hazards and obstacles, and education about using walking aids correctly.

  
  
• 
  

  All patients should undergo a medication review to identify any medication-induced contributors to falls, including cardiovascular medications that may lead to orthostatic hypotension, and neuropsychiatric medications that may alter balance, awareness, or cognition.

  
  
• 
  

  Vitamin D assessment for all patients and replacement for deficient patients.

  
  
• 
  

  A history of one fall and no other balance or gait disturbances should be followed by participation in an exercise program that includes balance and strength training. Examples of these programs can include physical therapy, tai chi, or other programs.

  
  
• 
  

  Two or more falls, and/or balance or gait difficulties should be followed by a detailed assessment and specialized physiotherapy.

Formal fall prevention programs can be divided into three main categories:

• 
  

  Single programs including one intervention component, ie, supervised exercises

  
  
• 
  

  Multicomponent programs including two or more intervention components, ie, exercises and environmental modifications

  
  
• 
  

  Multifactorial programs including two or more customized interventions for each participant targeted at patient-specific risk factors

A recent metaanalysis found that single interventions failed to show a beneficial effect on fall-related outcomes in the nursing home population, since they are most often physically frail and the fall is frequently of a multifactorial nature [17]. Single programs targeted at more functionally intact older adults may be more successful.

Interventions, particularly those with strength and balance training, can successfully increase muscle strength and functional abilities. Avoiding iatrogenic harm related to excessive hospitalization, testing and polypharmacy is important when frailty is recognized [18–20].

Vitamin D levels fall with aging and low levels are associated with sarcopenia, falls, hip fracture, disability, and mortality. When levels are low, vitamin D replacement can reverse some functional deterioration, providing support for modest daily vitamin D supplementation [21]. A metaanalysis found positive effects of vitamin D supplementation on muscle strength, gait and balance suggesting that vitamin D supplementation of 800–1,000 international units (IUs) daily was associated with improvements of muscle strength and balance [22]. Vitamin D reduces the number of falls in those who are deficient, and the combination of calcium and vitamin D for older patients in long-term care can reduce fractures.

Other than vitamin D, few pharmacological agents have been investigated to improve muscle strength, balance and falls, including angiotensin-converting enzyme inhibitors, testosterone, and insulin-like growth factors (IGFs); none of these has emerged as safe and effective for fall prevention at this time.

3.1 Evaluation

Sarcopenia is identified by the presence of two of the following criteria: low muscle mass, low muscle strength, and low physical performance [25]. While low muscle mass and strength can be evaluated in the research setting using various imaging techniques and dynamic strength testing, most practical testing focuses on physical performance. The most commonly used office tests include usual gait speed and the short physical performance battery (SPPB). Slow gait speed is currently the simplest screen for sarcopenia, with a cutoff point of 0.8 m/s over a 4–6-m course as the threshold for poor performance [25]. The SPPB is a more time-intensive assessment, involving repeated chair stands, balance testing and gait speed measurements [26]. Sarcopenia is only typically quantified in research settings, using handgrip strength (so-called handgrip dynamometer) or knee extension strength (so-called isokinetic dynamometer).