Both falling and bone fragility should be targeted: the limited effectiveness of exercise on fall prevention
We agree with the authors that falling should be targeted to prevent hip fracture (1). As pointed out in our previous rapid response (2), however, it would not be easy to effectively and continuously reduce fall risk in older adults over 75. Here we can confirm the situation by the latest well conducted randomised controlled trial (3), though there is no doubt regarding the importance of physical activity for health (4).
In women aged 75-85, living in community and at risk of falling, two-year balance training programme did not significantly reduce serious falls associated with fractures (hazard ratio 0.83, confidence interval 0.60 to 1.16) (3). The result might be due to lack of power (352 in the intervention group and 354 in the control group), but notably the effectiveness of this kind of exercise was limited (fall prevention by less than 20%). More importantly, the motivation in this age group was very low; indeed, less than 10% of the invited women agreed to participate the study and more than 25% of the participants stopped the training programme during the first month.
It is also important to note that skeletal fragility is determined not only by areal bone mineral density (BMD) but also by other factors including collagen-related bone quality (5). Bone fragility is associated with hip fracture, whereas the authors used two different terms, osteoporosis (defined by areal BMD) and bone fragility, interchangeably (6). Thus, it is reasonable to conclude that both falling and bone fragility should be targeted to prevent hip fracture in older adults (7).
Toshihiro Sugiyama, Yoon Taek Kim and Hiromi Oda
Department of Orthopaedic Surgery, Saitama Medical University, Saitama, Japan
1 Jarvinen TL, Michaelsson K, Jokihaara J, et al. Overdiagnosis of bone fragility in the quest to prevent hip fracture. BMJ 2015;350:h2088. (26 May.)
2 Sugiyama T, Kim YT, Oda H. Both falling and bone fragility should be targeted. www.bmj.com/content/350/bmj.h2088/rr-4. (2 June.)
3 El-Khoury F, Cassou B, Latouche A, et al. Effectiveness of two year balance training programme on prevention of fall induced injuries in at risk women aged 75-85 living in community: Ossebo randomised controlled trial. BMJ 2015;351:h3830. (22 July.)
4 Lee LM, Shiroma EJ, Lobelo F, et al. Effect of physical inactivity on major non-communicable diseases worldwide: an analysis of burden of disease and life expectancy. Lancet 2012;380:219-29.
5 Seeman E, Delmas PD. Bone quality: the material and structural basis of bone strength and fragility. N Engl J Med 2006;354:2250-61.
6 Compston J. Overdiagnosis of osteoporosis: fact or fallacy? Osteoporos Int 2015;26:2051-4.
7 Sugiyama T, Torio T, Miyajima T, Kim YT, Oda H. Romosozumab and blosozumab: alternative drugs of mechanical strain-related stimulus toward a cure for osteoporosis. Front Endocrinol 2015;6:54.
Competing interests: No competing interests