2001. exercise in the prevention of falls in older people a systematic literature review examining...

8/12/2019 2001. Exercise in the Prevention of Falls in Older People a Systematic Literature Review Examining the Rationale

1/12

Exercise in the Prevention of Falls inOlder PeopleA Systematic Literature Review Examining the Rationaleand the Evidence

Nick D. Carter,1,2,3Pekka Kannus4,5,6andKarim M. Khan1,3,7

1 Department of Family Practice, University of British Columbia, Vancouver,British Columbia, Canada

2 Defence Services Medical Rehabilitation Centre, Headley Court, Epsom, Surrey, England

3 School of Human Kinetics, University of British Columbia, Vancouver, British Columbia, Canada

4 The Bone Research Group, Accident and Trauma Research Center,The President Urho Kaleva Kekkonen Institute for Health Promotion Research, Tampere, Finland

5 Department of Surgery, Medical School, University of Tampere, Finland

6 Department of Surgery, Tampere University Hospital, Tampere, Finland

7 Osteoporosis Program, BC Womens Hospital and Health Centre, Vancouver,British Columbia, Canada

Contents

Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4271. The Age-Related Physiological Changes that Increase Risk for Falling Among

Older People . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4282. Integrated Rehabilitation-Based Model of Fall Risk Factors . . . . . . . . . . . . . . . . . . . . . . . 4293. Can Exercise Modify the Risk Factors for Falling? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4314. Can Exercise Decrease Fall Rate? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4315. Which Dimensions of Exercise are Key to Reducing Fall Risk? . . . . . . . . . . . . . . . . . . . . . 4326. Limitations in Present Research and Suggested Solutions . . . . . . . . . . . . . . . . . . . . . . . . 4327. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 435

Abstract Falls are a major source of death and injury in elderly people. For example,they cause 90% of hip fractures and the current cost of hip fractures in the US isestimated to be about 10 billion dollars. Age-related changes in the physiologicalsystems (somatosensory, vestibular and visual) which contribute to the mainte-nance of balance are well documented in older adults. These changes coupledwith age-related changes in muscle and bone are likely to contribute to an in-creased risk of falls in this population. The integrated rehabilitation-based modelof fall risk factors reveals multiple sites for interventions that may reverse fallrisk factors. Regular exercise may be one way of preventing falls and fall-related

fractures. The evidence for this contention comes from a variety of sources. Onthe basis of 9 randomised controlled studies conducted since 1996, exercise ap-pears to be a useful tool in fall prevention in older adults, significantly reducing

REVIEWARTICLE Sports Med 2001; 31 (6): 427-4380112-1642/01/0006-0427/$22.00/0 Adis International Limited. All rights reserved.


2/12

the incidence of falls compared with control groups. However, current limitationssuch as inconsistencies in the measurement of key dependent and independent

variables do not, at present, permit a meta-analysis of intervention trials. Furtherinvestigation, using trials designed with the current limitations in mind, is nec-essary to establish the optimum exercise programme to maximise fall preventionin older adults.

Fall-related injuries and deaths in older adults

are a major health problem worldwide,[1-4] with num-

bers of these injuries continuing to increase.[4] Ap-

proximately 30% of individuals over 65 years of

age fall at least once per year,[5,6] and about half ofthese do so recurrently.[7] In nonfatal falls almost

half of fallers are unable to get up without help[8]

and a fall may result in individuals considerably

reducing their activities for fear of future falls.[9] In

addition, there is an alarming trend towards an in-

creasing aging population, suggesting that these

problems are likely to become even more prevalent

in the future.[10]

A proportion of falls result in fractures. Over

90% of hip fractures result from falls,[11,12] and inindividuals who sustain a hip fracture, the outcome

is fatal in 12 to 20% of cases.[13,14] In nonfatal cases,

long-standing pain, disability and functional impair-

ment often ensue with tremendous socio-economic

consequences. In the UK alone, the estimated total

direct hospital costs arising from hip fractures are

1.3 billion (year of costing 2000),[15] and in the US

the annual costs associated with fall-related frac-

tures were estimated at $US10 billion.[1] Further-

more, the incidence of hip fractures continues torise steadily, even with age-adjusted figures.[16,17]

Regular exercise hasbeen proposed as onemethod

of preventing falls and therefore fall-related frac-

tures in older adults.[18] However, a great deal of

controversy surrounds both this premise[19] and the

specifics of the exercise prescription (i.e. type, fre-

quency, intensity and duration of the exercise) nec-

essary to prevent falls. Therefore, the aim of this

systematic literature review is to:

summarise the age-related physiological mech-anisms that increase the risk for falling in older

adults

improve understanding of the inter-relationships

between various fall risk factors by proposing

an integrated, rehabilitation-based risk factor

model

summarise the mechanisms whereby exercisemay plausibly reduce fall risk

systematically review the evidence as to whether

exercise can modify risk factors for falling and

influence fall rates

examine which dimensions of exercise are key

to reducing fall risk

propose directions for future research to address

the question: Can regular exercise prevent falls

and fall-related injuries in older individuals?

1. The Age-Related PhysiologicalChanges that Increase Risk for FallingAmong Older People

The incidence of falls increases with age.[2,4,7,20]

This is likely to be caused, in part, by age-related

deterioration of the 3 sensory systems that control

posture: vestibular, visual and somatosensory (fig.

1). The vestibular system provides input as to the

head position in relation to gravity and it also senses

how fast, and in which direction, the head is ac-

celerating. The visual system provides information

about the bodys location relative to its environ-

ment. The somatosensory system, in turn, is respon-

sible for discrimination of position and movements

of body parts. In the otolith of the ear, individuals

over 70 years of age have 40% fewer sensory cells

than do young adults.[21] Cutaneous vibratory sen-

sation and joint position sense are also significantly

diminished in the older person.[20,22] Peripheral vi-

sion is important in sway stabilisation,[23] and lowfrequency spatial information, mediated by the pe-

ripheral visual field, deteriorates with age.[24]

428 Carter et al.

Adis International Limited. All rights reserved. Sports Medicine 2001; 31 (6)


3/12

As well as involution of the sensory systems,

predisposition to both falls and fractures is also

likely to be increased by age-related changes in

muscle and bone. Studies have repeatedly found a

decline in lean muscle mass and strength in elderly

adults.[25-29] Overall muscle strength and mass de-

cline 30 to 50% between the ages of 30 and 80.[30]

As a result of the changes in muscle and sensory

function, 46% of adults 85 years and older and 36%

of adults over 75 years, complain of postural dis-

turbances compared with 13% of those aged 65 to

69 years.[31,32] Muscle mass and function are im-

portant for stability and correct balance, and are alsothought to give some protection to the proximal

femur by attenuating the hip-impact forces that oc-

cur in sideways falls in older adults.[33]

Although not a risk factor for falling, involu-

tional bone loss contributes to fracture risk, and

thus, warrants mention here. Cross-sectional stud-

ies indicate that bone loss commences in both sexes

from the middle of the third decade of life.[34-36] Of

many factors that may affect bone loss, menopause-

related sex-hormone deficiency is by far the mostimportant. In addition to the accelerated phase of

post-menopausal bone loss, a continuous, more grad-

ual process of age-related bone loss affects the hip

in both sexes and this may be caused by the effects

of reduced physical activity or the relative immo-

bility of the older adult.[37]

2. Integrated Rehabilitation-BasedModel of Fall Risk Factors

In excess of 130 different risk factors for falling

have been tabulated.[38] Because many of these risk

factors may be either directly correlated, or interact

in a complex manner, clinicians and scientists have

tried to group them in useful conceptual categories.

The simple dichotomy of risk factors for falling is

intrinsic, host factors (increased personal liability

to fall) and extrinsic, environmental factors (in-

creased opportunity to fall).[39,40] Extrinsic factors

have undoubted importance,[41] but have receivedrelatively little attention in medical strategies to

prevent falls.

The act of falling comprises 3 stages; fall initi-

ation, fall descent and fall impact.[42] As different

factors can act at each stage of the fall process, this

categorisation provides several areas of focus formedical intervention. This approach has, for exam-

ple, led to some researchers focusing on hip pro-

tectors to reduce fall impact, and thus, fracture

risk.[33]

In view of the complexity of interaction between

risk factors, we draw the readers attention to the

model of impairment and disability. The World

Health Organisation (WHO) definition ofimpair-

mentis any loss or abnormality of psychological,

physiological or anatomical structure or function.Disability, according to the International Classifi-

cation of Impairments, Disabilities or Handicaps

(ICIDH), and is defined as any restriction or lack

(resulting from impairment) of ability to perform

an activity in the manner or within the range con-

sidered normal for a human being.[43,44] Stroke, for

example, increases risk of falling, but it is muscle

weakness or sensory loss (impairment) and poor

balance (disability) resulting from the stroke that

produces the increased risk, not the stroke itself.The terms impairment and disability are widely

used in rehabilitation medicine and they are partic-

Vestibular systemVision

Somatosensorysystem

Fig. 1.The 3 sensory systems that control posture: vestibular,visual and somatosensory. (Artwork by Vicky Earle.)

Exercise and Fall Prevention in Older People 429



4/12

ularly useful for understanding the mechanisms that

underpin falling.

A strength of the rehabilitation model is that it

reveals multiple sites for interventions that may re-

verse fall risk factors (fig. 2). Clearly reversible

risk factors (e.g. multiple drug therapy) can be at-

tended to directly. The rehabilitation model indi-

cates that irreversible risk factors (e.g., stroke, osteo-arthrosis) cantheoretically be tackled by targeting the

specific impairments (therapy to improve strength

and proprioception) and the resultant disabilities

(therapy to improve gait). Thus, risk of falling may

be modifiable, even though the underlying medical

condition may not be. We believe that the integrated

model clarifies a field that can seem confusing when

risk factors are viewed in isolation.

Using this model, table I summarises some of

the many studies reporting specific impairmentsand disabilities that predispose to falls and the rel-

ative risk for falling that each risk factor imparts.

Aging, disuse andmedical conditions

such as:

Parkinson's diseasestrokehypotensiondepressionepilepsydementiaeye diseasesosteoarthrosisrheumatoid arthritisdizzyness and vertigoperipheral neuropathy

Impairments:

muscle functionjoint functionvestibular systemvisionproprioceptioncognition

Medication use,

such as:

sedativeshypnoticsantidepressantsantihypertensivesmultiple drugsalcohol

Disabilities:

static balancedynamic balancegait

Impact force attenuation

soft tissueslanding surface

Structural capacity of boneless than the applied load

Reduced bone mass

Altered bone geometryAltered bone architecture

Altered bone quality

Bone fracture

Fall initiation

Fall descent

Environmentalhazards

Fall impact

Fig. 2. Intrinsic impairments and disabilities can interplay with environmental hazards and predispose individuals to falls and fractures.

430 Carter et al.



5/12

In each impairment or disability, the relative risk

for falls was determined according to dichotomous

division (normal, abnormal) of continuous variables,

although the cut-off point varied between studies.

Figure 2 then summarises how intrinsic impairments

and disabilities, associated with aging and disease,

can mesh with extrinsic factors in predisposing to

falls and fractures.

3. Can Exercise Modify the Risk Factorsfor Falling?

From figure 2, it can be seen that interventionstrategies to modify risk factors for falls can be im-

plemented in a number of areas. Multifactorial hazard

reduction interventions have reduced falls,[41,71,72]

as have reductions in the number of medications

that elderly people use.[73] Multifactorial interven-

tions do not allow investigators to distinguish the

independent role of each modified risk factor, and

thus, it is not known which part of the intervention

is effective and which is not. Also, these multifac-

eted approaches are labour intensive and their cost-

effectiveness must be evaluated further.[41,74]

Exercise intervention can reduce many intrinsic

risk factors for falling (table II). Myers et al.[38] sug-

gested that strength, flexibility, balance and reaction

time were the factors most amenable to modification,

and thus, provide a rationale for exercise interven-

tion trials measuring the efficacy of exercise in the

prevention of falls in the elderly.

4. Can Exercise Decrease Fall Rate?

To address the question Does exercise interven-

tion reduce fall rate?we performed a computerised

literature search of the entire MEDLINE database,

covering the years 1966 to the present, using the

keywords: randomised controlled trials, exercise,

falls and elderly. All relevant articles were retrieved,

either locally, or by inter-library loan. The search

was not limited to the English literature, and articles

in all journals were considered, as were the refer-

ence lists of the published papers. Any relevant per-

sonal correspondence was also included. The refer-ences selected were reviewed by the authors, and

judged on their contribution to the body of knowl-

edge of this topic. A total of 13 studies were iden-

tified that had:

randomised controlled trial design

participants 60 years or older

falls as an outcome

exercise as intervention.

If exercise was included as part of a multifacto-

rial intervention, it was analysed only when the ex-

ercise component could clearly be separated from the

other interventions.

4.1 Results

Table III describes 13 randomised controlled trials

using exercise as the intervention for fall prevention

in community (n = 12) or institution dwelling (n =

1) older adults. The table reveals that the studies prior

to 1996 did not find that exercise reduced the risk

of falling in older adults while the 9 more recent

studies (since Wolf et. al.[117]) confirmed the value of

exercise in fall prevention. Five studies demonstrated

a significant reduction in falls[104,117,118,120,123] whilst

in the remaining 4,[73,119,121,122]

some reduction infalls was evident but not statistically significant. In

the Wolf et al.[117] study, a programme of Tai Chi

resulted in a 48% reduction of falls in participants

(mean age 76 years) compared with controls. Such

a reduction was not seen in the individuals who

followed a computerised balance-training pro-

Table I.Impairments and disabilities as risk factors for falls

Risk factor for falling Relative risk

for falls (rangebetween studies)

References

Impairment

Lower limb strength 0.5-10.3 6,45-49

Upper limb strength 1.5-4.3 3,6,9,50,51

Lower limb range of

motion

1.9 3

Sensation 0.6-5.0 45,47,52,53

Vestibular function 4.0 54

Vision 1.3-1.6 3,6,51,53,55-60

Cognition 1.2-5.0 5,6,58,61-65

Disability

Static balance 1.5-4.1 5,6,46,48,51,66-68

Dynamic balance/gait 1.6-3.3 3,5,6,9,48,50-52,65,

68-70




6/12

gramme. It is of interest that whilst the computer-

ised balance-training group developed greater sta-

bility on balance platform measures there was little

change in this parameter in the Tai Chi group.[124]

In the study by Campbell et al.[104] a physiotherapist-

led, but individualised programme of predominant-

ly lower limb strength and balance exercises for 30

minutes, 3 times per week plus additional walking,

resulted in a significantly reduced annual rate of

falls among women aged 80 years and older, com-

pared with control women. After 1 year, the relative

hazard for the first 4 falls in the exercise group

compared with controls was 0.68. The benefit of

exercise for the reduction of falls continued in the

2-year follow-up.[120] Buchner et al.,[118] in turn,

reported that in 75 community-dwelling elderly in-

dividuals who underwent strength, endurance and

flexibility training, fewer persons fell in the first

year (42%) compared with controls (60%) [p < 0.05].

These data were originally presented comparing 3

exercise groups (each with 25 participants; strength

and flexibility, endurance and flexibility, and alsostrength and endurance) with controls as part of the

Frailties and Injuries: Co-operative Studies of In-

tervention Techniques (FICSIT) meta-analysis (in

which 7 independent, randomised, controlled trials

assessed intervention efficacy in reducing falls).[125]

Analysis by these individual groups did not dem-

onstrate a significant reduction in the incidence of

falls.

In the meta-analysis of the 7 FICSIT trials, there

was a reduction in the fall incidence ratio (IR) fortreatment arms including exercise (IR = 0.90) and

balance (IR = 0.83).[125] However, repeat meta-

analysis excluding interventions with a nonexerc-

ise component, revealed that although the effects

of balance training remained (IR = 0.75), the pooled

estimate for overall exercise became nonsignificant

at IR = 0.87. There was no significant effect of the

other exercise domains (resistance, endurance and

flexibility) on the IR for falls.[125]

In 5 additional studies, to the 13 studies described

in table III, the exercise intervention arm combined

exercise with the correction of intrinsic (smoking/

alcohol/nutrition,[126] drug treatment[41]) risk fac-

tors or extrinsic (environmental hazards[126-129]) risk

factors. As the effect of exercise cannot be sepa-rated from the other components of the multifacto-

rial intervention, these studies cannot be analysed

further in terms of exercise and fall prevention.

5. Which Dimensions of Exercise areKey to Reducing Fall Risk?

Exercise and physical activity can be defined by

4 dimensions: type, frequency, intensity and dura-

tion.[130] Thus, we examined the 13 randomised con-

trolled trials outlined in table III to see whether theinterventions that reduced fall risk had certain ex-

ercise dimensions in common (table IV). Clearly,

the paucity of exercise dimension data and the lim-

ited power of studies undertaken to date, preclude

definite conclusions from being drawn and precise

exercise programmes from being prescribed. Al-

though, it is most encouraging that all of the more

recent studies found exercise to be a useful tool in

fall prevention in older persons (table III).

Exercise interventions in the meta-analysis ofthe 7 FICSIT trials pooled effect estimates of the

individual training types across the studies. Pool-

ing indicated a lower fall IR for balance, resistance

and flexibility training than for endurance training.

However, it must be noted that the confidence in-

tervals overlapped.[125]

6. Limitations in Present Research andSuggested Solutions

One of the major limitations in fall research isinconsistency in the approach to measuring key de-

pendent and independent variables such as cogni-

Table II. Intervention studies which have used exercise to modify

intrinsic risk factors for falls

Risk factorfor falling

Average improvement (%)[range between studies]

References

Muscle strength 6-174 41,75-100

Range of motion 0.5-18 84,93,96,101-103

Balance 7-53 41,77,83,86,90-94,

96,101,104-113

Gait 12-48 41,76,87,94,96,98,

99,108,109,113,114

Reaction time 0-4 77,91,115

432 Carter et al.



7/12

Table III. Summary of the randomised controlled trials that included exercise as an independently analyzed part of the trial in reducing or

delaying falls in older people

Author, date Participants: n,dwelling type

[mean age (y)]

Intervention Falls outcome

Reinsch et al.,

1992[116]230, C [74] (In) 3 groups: exercise (n = 57),

exercise/cognition (n = 72),

cognition/behavioural (n = 51).

Exercise: 60 min, 3per wk, 12mo. Stand-up,

step-up, stretching and movement to music.

Cognition/behavioural: health and safety

curriculum to prevent falls, relaxation, video

games. Exercise/cognition: 2per wk exercise,

once per wk cognition

(In) exercise (reported falling) = 24.7%;

cognition = 19.1%; exercise/cognition= 37.1%

(Ct) n = 50 (Ct) = 19.1% (NS)

MacRae et al.,1994[92]

80, C [>69] (In) n = 42, stand-up/step-up routine progressingto 4 sets of 10 repetitions.

60 min 3per wk

Fallers in 12mo period: (In) = 36%, (Ct) = 45%(NS)

(Ct) n = 38, hourly meeting each wk focusing on

health promotion and safety education

Mulrow et al.,

1994[93]194, I [>81] (In) n = 97, individually tailored one-one

physiotherapy sessions 3per wk for 4mo,

including range of motion, strength, balance,

transfer and mobility. Each session 30-40 min

Total number of falls: (In) = 79, (Ct) = 60 (NS).

Individuals with falls (%): (In) = 43, (Ct) = 37

(NS)

(Ct) n = 97, same frequency friendly visits

Lord et al., 1995[77] 197, C [72] (In) n = 100, 60-min exercise sessions, twice

weekly in 4 terms of 10-12wk. 4 sections per

session: warm-up, conditioning (aerobic,

strength, balance and flexibility), stretchingand relaxation

1 or more falls: (In) = 34.7%, (Ct) = 35.1%

(NS). 2 or more falls: (In) = 10.7%, (Ct) =

12.8% (NS)

(Ct) n = 97

Wolf et al., 1996[117] 200, C [80] (In) 2 groups: Tai Chi (TC) [n = 72] 15 min twice

daily at home for 4mo; computerised balance

training (BT) [n = 64]

Risk ratio of time to 1 or more falls as

compared with controls: (TC) = 0.525 (47.5%

reduction in fall incidence) p75] (In) 3 groups: gradual psychotropic withdrawal

over 14wk plus home-based programme of

exercises (see[104]) [n = 24], drug withdrawalonly (n = 24), exercise only (n = 21).

Individuals with falls: (In) drug withdrawal =

30% (p < 0.05), exercise = 39% [NS], (Ct) =51%

(Ct) n = 24 Continued over page




8/12

tion, vision, balance and strength. Furthermore, re-

porting falls data is sometimes prospective, some-

times short term retrospective, and sometimes long

term retrospective.[2] The definition of falls is gen-

erally agreed upon but it would advance the fieldgreatly if there was a collaboration on methodol-

ogy. If this were the case, it would permit a meta-

analysis of intervention trials. A meta-analysis would

be most beneficial given that absolute fall rates are

low and studies must be very large to have suffi-

cient power to detect differences between groups

in fall rates after intervention.

The preceding discussion of exercise interven-

tion studies undertaken to date reveals significant

deficiencies in the literature with respect to fall pre-vention in older adults. The oldest individuals are

particularly at risk of fall-related fractures,[41] and

therefore, fall prevention studies in this population

are urgently required.

Given the broad range of extrinsic and intrinsic

risk factors implicated in falls, it is extremely dif-

ficult to consciously control for all potentially con-founding variables when assessing a single inter-

vention, such as exercise.[2] Therefore, randomised

controlled trials are essential. Nevertheless, future

studies should also attempt to guarantee equal group

distribution by cognition, vision, other medical con-

ditions, drug use, previous activity levels and en-

vironmental hazards. Stratified randomisation might

be used for this purpose.

As no definitive exercise prescription can be made

on the basis of studies published to date, furtherwork is required to establish the optimum exercise

programmes to prevent falls both in healthy older

Table III.Contd

Author, date Participants: n,

dwelling type [age

(y)]

Intervention Falls outcome

Campbell et al.,

1999[120]152, C [84] 2y follow-up of the above 12mo study.[104]

(In) n = 71, individually tailored programme of

exercise. Physiotherapist visited 4in first 2mo

of the original study. Exercises 3per wk, 30 min

each, lower limb strength and balance plus

encouraged walking outside 3per wk

Total falls over 2y: (In) = 138, (Ct) = 220. Rate

of falls per person year: (In) = 0.83 [SD 1.29],

(Ct) = 1.19 [SD 1.93]. Relative hazard for falls

for the exercise group at 2y = 0.69 [95% CI for

(In) group compared with (Ct) 0.49, 0.97].

Relative hazard for a fall resulting in moderate

or severe injury = 0.63 (95% CI, 0.42, 0.95)(Ct) n = 81, equal care and frequent social visits

Steinberg et al.,

2000[121]252, C [75%

aged 50-74, 25%

aged >75]

12 month follow up. (In) 3 groups: exercise to

improve balance and strength, frequency and

duration of exercises not defined (n = 69); home

safety advice to modify environmental hazards

(n = 61); medical assessment to optimise health(n = 59)

Fall events per 100 person months:

(In) exercise = 6.37, (Ct) = 7.05. Time to first

fall, adjusted hazard ratio: 0.67 (95% CI 0.42,

1.07)

(Ct) n = 63, education and awareness of fall risk

factors

Rubenstein et al.,

2000[122]59, C [75] 12wk follow-up. (In) n = 31; strength, endurance,

mobility and balance training for 90 min, 3per

wk for 12wk

(In) 38.7% reported falling, (Ct) 32.1% reported

falling (NS). Falls adjusted for activity:

(In) 6/1000hr activity; (Ct) 16.2 (p < 0.05)

(Ct) n = 28, usual activities for the follow-up

period

Lehtola et al.,

2000[123]131 C [70-75] Additional 4mo follow-up after 6 month

intervention. (In) n = 92, an exercise class

including Tai Chi once weekly plus walking with

sticks, and home exercises each at least

3weekly for 6mo

Relative hazard for falls for the exercise group

in 10mo = 0.60 [95% CI for (In) compared with

(Ct) 0.43, 0.84]

(Ct) n = 39, usual activities for the follow-up

period

C = community-dwelling; CI = confidence interval; Ct = control group; I = institution-dwelling; In = intervention group; n = number of participants;

NS= not significant;p = significance level;SD = standard deviation.

434 Carter et al.



9/12

adults and in those with impairments and disabili-

ties.[2] For example, a once-weekly resistance train-

ing program has been shown to improve strength

and neuromuscular performance in older adults.[75]

This programme is very attractive, as the frequency

may promote programme adherence, though no stud-

ies have yet been performed using this programme

and measuring falls as an outcome. Furthermore,

such exercise programmes need to be accessible

(e.g. home or community centres) to target popu-

lations so that the results from these projects can

be easily translated into clinical practice.

Future research that attempts to answer the ques-tion: Can exercise prevent falls amongolder adults?

must clearly include an accurate assessment of both

falls[131] and fall-related injuries[41] as primary out-

come measures. Evidence exists that whilst fall risk

factors such as balance and strength may improve

with exercise,[76,77] falls themselves need not be

reduced and likewise, a reduction in falls may not

always be accompanied by a reduction in fall risk

factors.[117] In addition, fracture data have rarely

been collected in relation to fall studies,[41,127,132]

and therefore future studies should ideally be of

sufficient power to detect a difference in fracture

rates in the study populations, if any exists.[133]

7. Conclusion

Falls and related fractures are a major health

problem for older individuals and for modern

society.

Involutional changes in sensory and musculo-

skeletal structure and function among older peo-ple render them at increased risk of falls and

injuries.

Many intrinsic and extrinsic risk factors for falls

have been identified.

Exercise can theoretically modify the intrinsic

fall risk factors and thus prevent falls in elderly

people; however, the optimal exercise prescrip-

tion to prevent falls has not yet been defined.

Future trials measuring the role of exercise in

fall prevention need consistent methodology todetermine fall rates. Studies should focus on the

oldest and most frail individuals as a target pop-

ulation, better control for confounding vari-

ables, identify an optimal exercise programmefor specific groups of at-risk populations, and

use falls and fractures as fall-related injury pri-

mary outcomes. To achieve these goals will re-

quire the collaboration of researchers from

multiple centres.

Acknowledgements

Dr Carter was supported as an Royal Air Force Fellowwhile undertaking this research at the University of British

Columbia (Allan McGavinSports MedicineCentre andSchoolof Human Kinetics. The Fall-Free BCResearch Program issupported by the Vancouver Foundation (BCMSF), the BCSports Medicine Research Foundation, and the Canada Foun-dation for Innovation.

References1. Khan K, McKay H, Kannus P, et al. Physical activity and bone

health. Champaign (IL): Human Kinetics Publishers, 2001:169-177

2. Lord SR, Sherrington C, Menz HB. Falls in older people: riskfactors and strategies for prevention. Cambridge: CambridgeUniversity Press, 2001

3. Nevitt MC, Cummings SR, Kidd S, et al. Risk factors for recur-rent nonsyncopal falls. JAMA 1989; 261: 2663-8

4. Kannus P, Parkkari J, Koskinen S, et al. Fall-induced injuriesand deaths among older adults. JAMA 1999; 281: 1895-9

Table IV. Exercise dimensionsin the positive and negative outcome

studies using exercise in the prevention of falls

Exercise

dimension

Studies in which falls

were reduced

Studies in which falls

were not reduced

Type of activity

Endurance 118,122 77,119

Strength 104,118,120,122 73,77,92,93,116,119,121

Balance 104,117,120,122,123 73,77,92,93,116,121

Flexibility 104,118,120 77,92,93,116,119

Duration per session (min)

15 117

30 104 73

40 123 93

45 11960 118,123 77,92,116

90 122

Frequency of exercise (times/wk)

2 77

3 104,118,122 73,92,93,116,119

4-7 123

14 117




10/12

5. Tinetti ME, Speechley M, Ginter SF. Risk factors for fallsamong elderly persons living in the community. N Engl J Med

1988; 319: 1701-76. Campbell AJ, Borrie MJ, Spears GF. Risk factors for falls in acommunity-based prospective study of people 70 years andolder. J Gerontol 1989; 44 (4): M112-M7

7. Tinetti M, Speechley M. The prevention of falls among the el-derly. N Eng J Med 1989; 320: 1055-9

8. Tinetti ME, Lui WL, Claus E. Predictors and prognosis of in-stability to get up after falls among elderly persons. JAMA1993; 269: 65-70

9. Nevitt MC, Cummings SR,Kidd S, et al.Risk factors for injuriousfalls: a prospective study. J Gerontol 1991; 46: M164-M70

10. Kannus P, Palvanen M, Niemi S, et al. Epidemiology of osteo-porotic pelvic fractures in elderly people in Finland: sharpincreases in 1970-1997 and alarming projections for the newmillennium. Osteoporos Int 2000; 11: 443-8

11. Grisso JA, Kelsey JL, Strom BL, et al. Risk factors for falls asa cause of hip fractures in women. Lancet 1991; 324: 1326-31

12. Parkkari J, Kannus P, Palvanen M, et al. Majority of hip frac-tures occur as a result of a fall and impact on the greatertrochanter of the femur: a prospective controlled hip fracturestudy with 206 consecutive patients. Calcif Tissue Int 1999;65 (3): 183-7

13. Riggs BL, Melton LJ. Involutional osteoporosis. N Engl J Med1986; 314: 1676-86

14. Peck WA, Riggs BL, Bell NH, et al. Research directions inosteoporosis. N Engl J Med 1988; 85: 275-82

15. Torgerson DJ, Dolan P. The cost of treating osteoporotic frac-tures in the United Kingdom female population. OsteoporosInt 2000; 11: 551-2

16. Boyce WJ, Vessey MP. The rising incidence of fracture of theproximal femur. Lancet 1985; I: 150-1

17. Kannus P, Niemi S, Parkkari J, et al. Hip fractures in Finlandbetween 1970 and 1997 and predictions for the future. Lancet1999; 353: 802-5

18. Kannus P. Preventing osteoporosis, falls, and fractures among el-derly people. Promotion of lifelong activity is essential. BMJ1999; 318: 205-6

19. Feder G, Carter Y, Donovan S, et al. Few exercise programmesstudied have prevented falls [letter]. BMJ 1999; 318: 1695

20. Whanger AD, Wang HS. Clinical correlates of vibratory sensein elderly psychiatric patients. J Gerontol 1974; 29: 39-45

21. Rosenhall H. Degenerative changes in the ageing human ves-tibular geriatric neuroepithelia. Acta Otolaryngol 1973; 76:

208-2022. Skinner HB, Barrack RL, Cook SD. Age-related decline in pro-

prioception. Clin Orthop 1984; 184: 208-11

23. Paulus WM, Straube A, Brandt TH. Visual stabilization of pos-ture: physiological characteristics and clinical aspects. Brain1984; 107: 1143-63

24. Sekuler R, Hutman LP. Spatial vision and ageing: I. Contrastsensitivity. J Gerontol 1980; 35: 692-9

25. Gutmann E, Hanzlikova V. Motor unit in old age. Nature 1966;209: 921-2

26. Larsson L, Grimby G, Karlsson J. Muscle strength and speed ofmovement in relation to age and muscle morphology. J ApplPhysiol 1979; 46: 451-6

27. Cohn SH, Vartsky D, Yasumura S, et al. Compartmental body

composition based on total-body nitrogen, potassium and cal-cium. Am J Physiol 1980; 239: E524-E530

28. Johnson T. Age-related differences in isometric and dynamicstrength and endurance. Phys Ther 1982; 7: 985-9

29. Murray PM, Duthie EH, Gambert SR, et al. Age-related differ-ences in knee muscle strength in normal women. J Gerontol

1985; 40: 275-8030. Frischknecht R. Effect of training on muscle strength and motorfunction in the elderly. Reprod Nutr Dev 1998; 38: 167-74

31. Gerson LW, Jarjoura D, McCord G. Risk of imbalance in elderlypeople with impaired hearing or vision. AgeAgeing 1989; 18:31-4

32. Sixt E, Landahl S. Postural disturbances in a 75 year-old popu-lation: I. Prevalence and functional consequences. Age Age-ing 1987; 16: 393-8

33. Kannus P, Parkkari J, Niemi S, et al. Prevention of hip fracturein elderly people with use of a hip protector. N Engl J Med2000; 343: 1506-13

34. Riggs BL, Wahner HW, Dunn WL. Differential changes in bonemineral density of the appendicular and axial skeleton withageing. J Clin Invest 1981; 67: 328-35

35. Geusens P, Derueker J, Verstraeten A, et al. Age and sex andmenopause-related changes in vertebral and peripheral bone:population study using dualand single photon absorptiometryand radiogammetry. J Nucl Med 1986; 27: 1540-9

36. Haapasalo H, Kannus P, Sievanen H, et al. Development of mass,density and estimated mechanical characteristics of bones inCaucasian women. J Bone Miner Res 1996; 11: 1751-60

37. Jones G, Nguyen T, Sambrook P, et al. Progressive bone loss inthe femoral neck in elderly people: longitudinal findings fromthe Dubbo osteoporosis epidemiology study. BMJ 1994; 312:691-5

38. Myers AH, Young Y, Langlois JA. Prevention of falls in theelderly. Bone 1996; 18 (1 Suppl.): 87S-101S

39. Nickens H. Intrinsic factors in falling among the elderly. Arch

Intern Med 1985; 145: 1089-9340. Davis JW, Ross PD, Nevitt MC, et al. Risk factors for falls and

serious injuries among older Japanese women in Hawaii. JAm Geriatr Soc 1999; 47: 792-8

41. Tinetti ME, Baker DI, McAvay G. A multifactorial interventionto reduce the risk of falling among elderly people living in thecommunity. N Engl J Med 1994; 331: 821-7

42. Hayes WC, Myers ER, Robinovitch SN, et al. Etiology and pre-vention of age-related hip fractures. Bone 1996; 18: 77S-86S

43. World Health Organization (WHO). International classificationof impairments, disabilities and handicaps. Geneva: WHO,1980; 25-31

44. Schuntermann MF. The international classification of impair-ments, disabilities and handicaps (ICIDH) results and prob-lems. Int J Rehab Res 1996; 19: 1-11

45. Robbins AS, Rubenstein LZ, Josephson KR, et al. Predictors offalls among elderly people, results of two population basedstudies. Arch Int Med 1989; 149: 1628-33

46. Studenski S, Duncan PW, Chandler J. Postural responses andeffector factors in persons with unexplained falls: results andmethodologic issues. J Am Geriatr Soc 1991; 39: 229-34

47. Sorock GS, Labiner DM. Peripheral neuromuscular dysfunc-tion and falls in an elderly cohort. Am J Epidemiol 1992; 136:584-91

48. Lord SR, Ward JA, Williams P, et al. Physiological factors as-sociated with falls in older community-dwelling women. JAm Geriatr Soc 1994; 42: 1110-7

49. Tinetti ME. Factors associated with serious injury during fallsby ambulatory nursing home residents. J Am Geriatr Soc 1987;

35: 644-850. Wickham C, Cooper C, Margetts BM, et al. Muscle strength,

activity, housing and the risk of falls in elderly people. AgeAgeing 1989; 18: 47-51

436 Carter et al.



11/12

51. Buchner DM, Larson EB. Falls and fractures in patients withAlzheimer type dementia. JAMA 1987; 257: 1492-5

52. Lipsitz LA, Jonsson PV, Kelley MM, et al. Causes and correlatesof recurrent falls in ambulatory frail elderly. J Gerontol 1991;46: M114-M22

53. Cwikel J. Falls among elderly people living at home: medicaland social factors in a national sample. Isr J Med Sci 1992;28: 446-53

54. Kerber K, Enritto J, Jackobson K, et al. Disequilibrium in olderpeople: a prospective study. Neurology 1998; 51: 574-80

55. Jantti PO, Pyykko VI, Hervonen AL. Falls among elderly nurs-ing home residents. Public Health 1993; 107: 80-96

56. Marion ET, Gaskell A. Dark adaptation and falls in the elderly.Gerontology 1991; 37: 221-4

57. Arfken CL, Lach HW, McGee S, et al. Visual acuity, visualdisturbances and falling in the elderly. J Ageing Health 1994;6: 38-50

58. Prudham D, Evans JG. Factors associated with falls in the el-derly: a community study. Age Ageing 1981; 10: 141-6

59. Tobis JR,Reinsch S, Swanson JM,et al.Visual perception dom-inance of fallers among community-dwelling older adults. JAm Geriatr Soc 1985; 33: 330-3

60. Lord SR, Webster IW. Visual field dependence in elderly fallersand non-fallers. Int J Ageing Hum Dev 1990; 31: 267-77

61. Buchner DM, Larson EB. Transfer bias and the association ofcognitive impairment with falls. J GenInt Med1988; 3:254-9

62. Ryynanen OP, Kivela SL, Honkanen R, et al. Recurrent elderlyfallers. Scan J Prim Care 1992; 10: 277-83

63. Mahoney J, Sager M, Dunham MC, et al. Risk of falls afterhospital discharge. J Am Geriatr Soc 1994; 42: 269-74

64. Lord SR, Clark RD, Webster IW. Physiological factors associ-

ated with falls in an elderly population. J Am Geriatr Soc1991; 39: 1194-200

65. Lord SR, Clark RD. Simple physiological and clinical tests foraccurate prediction of falling in older people. Gerontology1996; 42: 199-203

66. Yip YB, Cumming RG. The association between medicationsand falls in Australian nursing-home residents. Med J Aust1994; 160: 14-8

67. Anacker SL, DiFabio RP. Influence of sensory inputs on stand-ing balance in community-dwelling older elders with a recenthistory of falling. Phys Ther 1992; 72: 575-84

68. Lord SR, Sambrook PN, Gilbert C, et al. Postural stability, fallsand fractures in the elderly: results from the Dubbo Osteopo-rosis Epidemiology Study. Med J Aust 1994; 160: 684-91

69. Clark RD, LordSR, Webster IW. Clinical parameters associatedwith falls in an elderly population. Gerontology 1993; 39:117-23

70. TenoJ, Kiel DP, Mor V. Multiple stumbles: a risk factor for fallsin community-dwelling elderly. J Am Geriatr Soc 1990; 38:1321-5

71. Ray WA, Taylor JA, Meador KG, et al. A randomized trial of aconsultation service to reduce falls in nursing homes. JAMA1997; 278: 557-62

72. Close J, Ellis M, Hooper R, et al. Prevention of falls in theelderly trial (PROFET): a randomized controlled trial. Lancet1999; 353: 93-7

73. Campbell AJ, Roberton MC, Gardner MM, et al. Psychotropicmedicine withdrawal and a home-based exercise program toprevent falls: a randomized controlled trial. J Am Geriatr Soc

1999; 47: 850-374. Rizzo JA, Baker DI, McAvay G, et al. The cost-effectiveness

of a multifactorial target prevention program for falls amongthe community elderly persons. Med Care 1996; 34: 954-69

75. Taaffe D, Duret C, Wheeler S, et al. Once-weekly resistanceexerciseimproves muscle strengthand neuromuscularperfor-

mance in older adults. J Am Geriatr Soc 1999; 47: 1208-1476. Fiatarone MA,ONeil EF, Ryan ND,et al. Exercise training andnutritionalsupplementation forphysical frailtyin veryelderlypeople. N Engl J Med 1994; 330: 1769-5

77. Lord SR, Ward JA, Williams P, et al. The effect of a 12-monthexercise trial on balance, strength, and falls in older women:a randomized controlled study. J Am Geriatr Soc 1995; 43:1198-206

78. Nichols JF, Omizo DK, Peterson KK, et al. Efficacy of heavy-resistance exercise for active women over sixty: muscularstrength, body composition and program adherence. J AmGeriatr Soc 1993; 41: 205-10

79. Aniannsson A, ZetterbergC, HedbergM, et al. Impaired musclefunction with aging. Clin Orthop 1984; 191: 193-201

80. Frontera WR, Meredith CN, OReilly KP, et al. Strength con-

ditioning in older men: skeletal muscle hypertrophy and im-proved function. J Appl Physiol 1988; 64: 1038-44

81. Fiatarone MA, Marks EC, Ryan ND, et al. High-intensity train-ing in nonagenarians. JAMA 1990; 263: 3029-34

82. NelsonME, Fiatarone MA, Morganti CM,et al. Effects ofhigh-intensity strength training on multiple risk factors for osteo-porotic fractures: a randomized controlled trial. JAMA 1994;272: 1909-14

83. Kronhed AC, Moller M. Effects of physical exercise on bonemass, balance skill and aerobic capacity in women and menwith low bone mineral density, after one year of training: aprospective study. Scand J Med Sci Sports 1998; 8: 290-8

84. Bravo G, Gauthier P, Roy P-M, et al. Impact of a 12-monthexercise program on the physical and psychological health of

osteopenic women. J Am Geriatr Soc 1996; 44: 756-6285. Peterson SE, Peterson MD, Raymond D, et al. Muscular

strength and bone density and weight training in middle-agedwomen. Med Sci Sports Exerc 1991; 23: 449-504

86. Malmros B, Mortenson L, Jensen MB, et al. Positive effects ofphysiotherapy on chronic pain and performance in osteopo-rosis. Osteoporosis Int 1998; 8: 215-21

87. Sherrington C, Lord SR. Home exercise to improve strengthand walking velocity after hip fracture: a randomized control-led trial. Arch Phys Med Rehabil 1997; 78: 208-12

88. McMurdo ME, Rennie L. A controlled trial of exercise by res-idents of old peoples homes. Age Ageing 1993; 22: 11-5

89. Charlette SL, McEvoy L, Pyka G, et al. Muscle hypertrophy inresponse to resistance trainingin older women. J ApplPhysiol1991; 70: 1912-6

90. Lord S. The effects of a community exercise program on fracturerisk factors in older women. Osteoporos Int 1996; 6: 361-7

91. Lord S, Castell S. Physical activity program for older persons:effect on balance, strength, neuromuscular control and reac-tion time. Arch Phys Med Rehabil 1994; 75: 648-52

92. MacRae PG, Feltner ME, Reinsch S. A 1-year exercise programfor older women: effects on falls, injuries and physical per-formance. J Ageing Phys Act 1994; 2: 127-42

93. Mulrow CD, Gerety MB, Kanten D, et al. A randomized trialof physical rehabilitation for very frail nursing home resi-dents. JAMA 1994; 271: 519-24

94. Sauvage SR, Myklebust BM, Crow Pan J. A clinical trial ofstrengthening and aerobic exercise to improve gait and bal-ance in elderly nursing home residents. Am J Phys Med

Rehabil 1992; 71: 333-4295. Skelton D, YoungA, Greig C, et al.Effects of resistance training

on strength, power,and selected functional abilities of womenaged 75 and older. J Am Geriatr Soc 1995; 43: 1081-7




12/12

2001. exercise in the prevention of falls in older people a systematic literature review examining...

Documents