Intended for healthcare professionals

Rapid response to:

Analysis

Shifting the focus in fracture prevention from osteoporosis to falls

BMJ 2008; 336 doi: https://doi.org/10.1136/bmj.39428.470752.AD (Published 17 January 2008) Cite this as: BMJ 2008;336:124

Rapid Response:

Authors' reply: Focusing fracture prevention on falls!

We welcome the numerous responses to our paper entitled “Shifting the
Focus in Fracture Prevention from Osteoporosis to Falls” (1). There
appears to be a broad consensus on one of the most important issues put
forward in our paper – population-wide fracture-preventing interventions
should be simple and feasible. As already suggested in 1991 by Law et al.
(2), primary prevention of any aging-related public health problem must
rely on improving the health-related lifestyle of the entire population.
In the case of age-related fractures, strength and balance training,
sufficient intake of vitamin D and calcium, and smoking cessation are
appropriate measures (2, 3).

Falls, the single most important risk factor for fractures in elderly
adults, have a multifactorial aetiology; therefore possible preventive
measures are protean. We agree with the responses that suggested
population-level interventions to reduce the burden of fractures including
home visits accompanied with possible safety-enhancing alterations, the
assessment of visual function (which in fact, is included in the
physiological profile assessment instrument (4) mentioned in our paper),
the “baffiectomy”, and treating conditions such as nocturia or obstructive
sleep apnea.

We also want to thank Drs. Bayly and Masud for encouraging discussion
of the role of bone-targeted pharmacotherapy. We share the authors’ view
that theoretically an optimal strategy for prevention of fractures in
elderly people would include interventions targeted at reducing falls and
improving bone strength. However, the continuing rise in health care costs
means that health care is under strict economic scrutiny. Although our
duty as doctors is clearly to serve our patients, there is increasing
recognition that, particularly in publicly-funded health care systems, it
is important to consider both the cost and the benefit of treatment.
Patients, therapists and those paying for the treatment have a right to
know how many older adults needed treatment (the number needed to treat,
NNT) to prevent one (hip) fracture and at what cost. In many countries,
large-scale fracture prevention with medication is not economically
viable.

Bearing this in mind, we add the following to Drs. Bayly and Masud’s
response:

1) Bayly and Masud infer that our claim that “the risk of falling
still remains overlooked in clinical practice as well as in important
publications on prevention of fractures” would be flawed. We are happy to
learn that numerous agencies in UK have adopted falls prevention along
with bone-targeted pharmacotherapy as a means to prevent fractures.
Whether this is true in everyday practice in UK and other countries
requires audit-type evidence (5). Nevertheless, as evidenced by the title
of our paper, we seriously question whether the relative emphasis afforded
to falls and drugs in fracture prevention publications is correct. We
respectfully reiterate that the focus of these communications does not do
justice to the importance of falling as the primary risk factor for
fractures. Many fracture prevention papers merely provide a token ‘nod’ to
falls in a perfunctory paragraph. Prospective studies indicate that fall
events put the patient at greater risk of fracture than does relative bone
fragility.

2) Bayly and Masud point to absence of evidence that falls
preventions would prevent fractures in community dwelling older people.
They argue that the falls-prevention interventions we listed do not
support claims for a 50% reduction in fracture rates. In fact, these
interventions point to the right direction or fracture reduction, but as
we noted in our paper, “Unfortunately, no study into preventing falls has
had sufficient power to use fractures as a primary outcome”. In this
respect, one should also recall that absence of evidence is not a proof of
absence of an effect (rather absence of evidence, only). Bayly and Masud
emphasise Gates and colleagues’ systematic review (6) to argue that
multifactorial falls prevention interventions do not work. However, there
are limitations in the studies that were available for review (the
quality, content and implementation-intensity of the intervention studies
varied considerably resulting in considerable heterogeneity in the
results), and therefore, it cannot be used as strong evidence against any
single falls prevention intervention.

Our main arguments for advocating fall prevention’s primacy over
treatment of osteoporosis to prevent fractures are; (i) falling is a
strong and very common risk factor of fracture in elderly populations (as
opposed to moderate role of low BMD or osteoporosis), (ii) screening for
propensity to falls (by simple questionnaires) is valid, cheap, and
readily available in every health-care setting (unlike DXA scanning), and
(iii) falls can be prevented (level 1 evidence, especially for exercise).
Importantly, we also emphasise that, (iv) many of the strategies to
prevent falls in the elderly populations, such as strength and balance
training, provide additional health benefits beyond fracture prevention
(7).

3) We agree with Bayly and Masud that generic alendronate will reduce
the cost of treating osteoporosis, but it must be kept in mind that for
the total cost calculation, we must also take into account the costs of
the clinic visits, DXA scanning, and possible laboratory examinations.
Also, treatment of possible adverse effects should be included. In fact,
the National Institute of Health and Clinical Excellence (NICE) in the UK
has recently issued health economic appraisals for the primary and
secondary prevention of osteoporotic fracture that are more restrictive
than previous guidelines for the management of osteoporosis.

Thus, we still have concerns about the prices of many of the bone-
specific drugs and the subsequent total costs, and especially the alleged
effectiveness of bone-targeted pharmacotherapy. As our colleagues
appreciate, before one can enter into discussion on the possible cost-
effectiveness of any preventive pharmacotherapy (or any other health
measure), a specific hierarchy of evidence has to be obtained. First, it
needs to be shown that the given health measure can work under idealized
circumstances: Drugs are tested in carefully selected populations in so
called efficacy trials. Although there is evidence of the efficacy of
bisphosphonates on hip fractures in women aged 65-80 years of age
(relative risk [RR] 0.58; 95% credible interval [CrI], 0.42-0.80) (8),
there is yet no evidence that such approach actually works: the
effectiveness of bone-targeted pharmacotherapy given to individuals with
health states that would have led to their exclusion from the pivotal RCTs
is still completely lacking. We iterate that in clinical trials that
approached the design of an effectiveness study (drugs given to less
selected, high-risk population), there was no significant effect of
bisphoshonates in preventing hip fracture (9, 10).

Also, it is important for readers to recall that the alleged cost-
effectiveness of bone-targeted pharmacotherapy is based on calculations
that have assumed an unrealistic 100% compliance with therapy. The
clinical reality is that at least 50% of patients discontinue therapy
within 1 year and the decline seems to continue thereafter (11). Also cost
studies have extrapolated the magnitude of the anti-fracture efficacy from
younger populations to those aged +80 years (12). Such flaws invalidate
the estimates.

4) Drs. Bayly and Masud also pose great expectations for the new
fracture prediction model called Absolute Fracture Risk (13). They suggest
that this would overcome the flaws in the prevailing tool for identifying
those at increased risk of fracture, and thus, help identify those who
likely benefit from pharmacotherapy. However, as discussed in our
Analysis, we claim that even the theoretical basis for such enthusiasm
fails under scrutiny (See paragraph “Absolute fracture risk” and Figure 2
of our paper, www.bmj.com).

In brief, there are two fundamental flaws: i) In agreement with our
notions, a recent commentary by Browner (14) specifically assessed the new
concept (Absolute Fracture Risk algorithm) and showed that the addition of
clinical risk factors to BMD did not greatly improve risk prediction,
particularly among those aged 70 and older, in whom the vast majority of
hip fractures occur. Similar to the BMD-based fracture prediction it is
supposed to replace, the Absolute Fracture Risk-algorithm undeniably works
at the population level - essentially showing that the set of risk factors
have a statistically significant association with fractures. However, in
clinical practice (at the individual level), a tool should have excellent
discriminative ability, i.e., to be able to predict with high sensitivity
and specificity who is going to have a fracture and who is not.
Unfortunately, it does not (14). The difficulty in developing a clinically
useful and viable prediction tool was elegantly exemplified by Browner as
follows: Being able to predict a coin toss 51% of the time can make one
rich in the long run, but won’t impress someone who watches your
performance for “only” a few hundred flips (14). ii) Before such a
completely new algorithm could even theoretically be advocated for wide
use, one should have actual RCT-derived evidence to show that bone-
targeted pharmacotherapy indeed reduces the incidence of hip fractures in
the “high-fracture risk” people classified according to the new criteria.
At present, there is no data to suggest this would be the case (9, 10,
15).

5) Finally, Drs. Bayly and Masud call attention to the importance of
secondary prevention to reduce fracture rates. Although we share their
view on the importance of secondary prevention, we must respectfully
disagree with their proposition that “an optimal care” would comprise of
treatment with bone-targeted pharmacotherapy. Although it is true that
those with a previous fracture have about 2-2.5 times increased relative
risk of future fracture (for example, according to a recent population-
based study in Finland, the absolute risk of secondary hip fracture is 5%
and 8% in the first two years after hip fracture (16)), this approach has
problems.

First, many fractures in the elderly population occur without BMD-
defined osteoporosis and recent previous fracture. The notion that up to
50% of hip fracture patients have had a fracture before is misleading
since many of these previous fractures (such as radius fracture) occurred
as long as 30 years before the index hip fracture; it would not be
appropriate to treat such patients with bone-specific drugs for decades.
As only about 10% of hip fracture patients have had a previous hip
fracture, treatment of hip fracture patients with bone-specific drugs, no
matter how effective, will not address the entire problem. Second, and
even more importantly, the increased risk of secondary fracture seems to
be mostly attributable to extraskeletal risk factors, not osteoporosis
(1). Thus, a policy of initiating pharmacotherapy on all patients with a
prior “fragility” fracture would - at best - have a negligible effect on
the population burden of fractures. It would, however, be associated with
astronomical costs.

In a recent BMJ Analysis paper, Mangin et al. (17) called for fresh,
broad-minded thinking into preventive health care in elderly people. They
reminded us that preventive treatments do not relieve suffering directly
but reduce the risk of future suffering. Prevention has side effects other
than the hazards of the treatment - in particular, the shadow cast over a
currently healthy life by the threat of disease, which might be magnified
in elderly people for whom mortality looms larger. When we convey risk to
any patient we should be cautious - it is like putting a drop of ink into
the clear water of the patient’s identity, which can never be quite clear
again (17). The interventions that have been shown to reduce falls, and
injurious falls, meet Mangin et al.’s criteria as being both fresh and
feasible. We feel that it is time to shift the focus in fracture
prevention research and interventions from bone-specific agents to efforts
to reduce falls and related injuries.

1. Jarvinen TL, Sievanen H, Khan KM, Heinonen A, Kannus P. Shifting
the focus in fracture prevention from osteoporosis to falls. Bmj
2008;336(7636):124-6.

2. Law MR, Wald NJ, Meade TW. Strategies for prevention of
osteoporosis and hip fracture. Bmj 1991;303(6800):453-9.

3. Osteoporosis prevention, diagnosis, and therapy. Jama
2001;285(6):785-95.

4. Lord SR, Menz HB, Tiedemann A. A physiological profile approach to
falls risk assessment and prevention. Phys Ther 2003;83(3):237-52.

5. Salter AE, Khan KM, Donaldson MG, Davis JC, Buchanan J, Abu-Laban
RB, et al. Community-dwelling seniors who present to the emergency
department with a fall do not receive Guideline care and their fall risk
profile worsens significantly: a 6-month prospective study. Osteoporos Int
2006;17(5):672-83.

6. Gates S, Fisher JD, Cooke MW, Carter YH, Lamb SE. Multifactorial
assessment and targeted intervention for preventing falls and injuries
among older people in community and emergency care settings: systematic
review and meta-analysis. Bmj 2008;336(7636):130-3.

7. Pedersen BK, Saltin B. Evidence for prescribing exercise as
therapy in chronic disease. Scand J Med Sci Sports 2006;16 Suppl 1:3-63.

8. Nguyen ND, Eisman JA, Nguyen TV. Anti-hip fracture efficacy of
biophosphonates: a Bayesian analysis of clinical trials. J Bone Miner Res
2006;21(2):340-9.

9. McCloskey EV, Beneton M, Charlesworth D, Kayan K, deTakats D, Dey
A, et al. Clodronate reduces the incidence of fractures in community-
dwelling elderly women unselected for osteoporosis: results of a double-
blind, placebo-controlled randomized study. J Bone Miner Res
2007;22(1):135-41.

10. McClung MR, Geusens P, Miller PD, Zippel H, Bensen WG, Roux C, et
al. Effect of risedronate on the risk of hip fracture in elderly women.
Hip Intervention Program Study Group. N Engl J Med 2001;344(5):333-40.

11. Compston JE, Seeman E. Compliance with osteoporosis therapy is
the weakest link. Lancet 2006;368(9540):973-4.

12. Jarvinen TL, Kannus P. Re: "Half the burden of fragility
fractures in the community occur in women without osteoporosis. When is
fracture prevention cost effective?" by Sanders et al. Bone
2006;39(6):1390-1; author reply 1391-2.

13. Kanis JA, Oden A, Johnell O, Johansson H, De Laet C, Brown J, et
al. The use of clinical risk factors enhances the performance of BMD in
the prediction of hip and osteoporotic fractures in men and women.
Osteoporos Int 2007;18(8):1033-46.

14. Browner WS. Predicting Fracture Risk: Tougher Than It Looks.
BoneKEy 2007;4(8):226-230.

15. Lyles KW, Colon-Emeric CS, Magaziner JS, Adachi JD, Pieper CF,
Mautalen C, et al. Zoledronic acid and clinical fractures and mortality
after hip fracture. N Engl J Med 2007;357(18):1799-809.

16. Lonnroos E, Kautiainen H, Karppi P, Hartikainen S, Kiviranta I,
Sulkava R. Incidence of second hip fractures. A population-based study.
Osteoporos Int 2007;18(9):1279-85.

17. Mangin D, Sweeney K, Heath I. Preventive health care in elderly
people needs rethinking. Bmj 2007;335(7614):285-7.

Competing interests:
None declared

Competing interests: No competing interests

17 February 2008
Teppo L Järvinen
Orthopaedic resident
Karim M Khan, Harri Sievänen, Ari Heinonen, and Pekka Kannus
Tampere University Hospital, P.O. Box 2000, 33520 Tampere, Finland