To stop or not to stop, that is the question

Treatment aimed at preventing fractures should be stopped if evidence of continued antifracture efficacy is lacking, if continued treatment increases bone fragility by adversely affecting matrix properties, and if stopping does not increased bone fragility. Credible evidence of antifracture efficacy beyond 5 years is lacking because of attrition of the cohort originally allocated to treatment or placebo and lack of controls. Prolonged suppression of remodeling is associated with accumulation of microdamage, advanced glycation products and increased tissue mineral density in animal studies but the structural benefits appear to out weight these adverse effects. Atypical minimal trauma subtrochanteric fractures are associated with prolonged treatment in human subjects but these are exceedingly rare. Stopping treatment does result in the reemergence of remodeling, rapidly with some drugs, more slowly with others while fracture rates are increased in poor compliers to treatment. Thus, within the constraints of limited evidence, I infer that stopping therapy is more likely to do net harm than continuing therapy - treatment should be continued in the majority of individuals.

[1]  D. Burr,et al.  Suppressed Bone Turnover by Bisphosphonates Increases Microdamage Accumulation and Reduces Some Biomechanical Properties in Dog Rib , 2000, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[2]  S. Cummings,et al.  Risk of fracture among women who lose bone density during treatment with alendronate. The Fracture Intervention Trial , 2005, Osteoporosis International.

[3]  Jacques P. Brown,et al.  Comparison of the Effect of Denosumab and Alendronate on BMD and Biochemical Markers of Bone Turnover in Postmenopausal Women With Low Bone Mass: A Randomized, Blinded, Phase 3 Trial , 2009, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[4]  Ego Seeman,et al.  Bone quality: the material and structural basis of bone strength , 2008, Journal of Bone and Mineral Metabolism.

[5]  T. Spector,et al.  Effects of long-term strontium ranelate treatment on the risk of nonvertebral and vertebral fractures in postmenopausal osteoporosis: Results of a five-year, randomized, placebo-controlled trial. , 2008, Arthritis and rheumatism.

[6]  I. Reid,et al.  Effect of calcium supplementation on hip fractures , 2008, Osteoporosis International.

[7]  I. Reid,et al.  Effects of Intravenous Zoledronate on Bone Turnover and BMD Persist for at Least 24 Months , 2008, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[8]  F. Coxon An update on the pharmacology of bisphosphonates and analogues with lower bone affinity , 2008 .

[9]  J. Rodriguez-Portales,et al.  Ten years' experience with alendronate for osteoporosis in postmenopausal women. , 2004, The New England journal of medicine.

[10]  Health risks and benefits 3 years after stopping randomized treatment with estrogen and progestin. , 2008, JAMA.

[11]  N. Watts,et al.  Mechanisms of action of bisphosphonates: similarities and differences and their potential influence on clinical efficacy , 2008, Osteoporosis International.

[12]  N. Watts,et al.  Fracture risk remains reduced one year after discontinuation of risedronate , 2008, Osteoporosis International.

[13]  J. S. San Martin,et al.  Effect of denosumab on bone density and turnover in postmenopausal women with low bone mass after long-term continued, discontinued, and restarting of therapy: a randomized blinded phase 2 clinical trial. , 2008, Bone.

[14]  Richard L Prince,et al.  Effects of calcium supplementation on clinical fracture and bone structure: results of a 5-year, double-blind, placebo-controlled trial in elderly women. , 2006, Archives of internal medicine.

[15]  P. Lips,et al.  Mean wall thickness of trabecular bone packets in the human iliac crest: Changes with age , 1978, Calcified Tissue Research.

[16]  D. Mellström,et al.  Seven Years of Treatment with Risedronate in Women with Postmenopausal Osteoporosis , 2004, Calcified Tissue International.

[17]  O. Johnell,et al.  Ten-year risk of osteoporotic fracture and the effect of risk factors on screening strategies. , 2002, Bone.

[18]  J. Zerwekh,et al.  Severely suppressed bone turnover: a potential complication of alendronate therapy. , 2005, The Journal of clinical endocrinology and metabolism.

[19]  J. Rungby,et al.  Hormone Replacement Therapy Prevents Osteoclastic Hyperactivity: A Histomorphometric Study in Early Postmenopausal Women , 1999, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[20]  P. Barber,et al.  Vascular events in healthy older women receiving calcium supplementation: randomised controlled trial , 2008, BMJ : British Medical Journal.

[21]  Ego Seeman,et al.  Bone Fragility: Failure of Periosteal Apposition to Compensate for Increased Endocortical Resorption in Postmenopausal Women , 2006, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[22]  Dennis M. Black,et al.  Relationships between bone mineral density and incident vertebral fracture risk with raloxifene therapy , 2002 .

[23]  D. Burr,et al.  Raloxifene enhances vertebral mechanical properties independent of bone density. , 2006, Bone.

[24]  E. Seeman Is a change in bone mineral density a sensitive and specific surrogate of anti-fracture efficacy? , 2007, Bone.

[25]  D. Burr,et al.  Low bone mineral density is associated with bone microdamage accumulation in postmenopausal women with osteoporosis. , 2007, Bone.

[26]  D. Burr,et al.  Alterations in canine vertebral bone turnover, microdamage accumulation, and biomechanical properties following 1-year treatment with clinical treatment doses of risedronate or alendronate. , 2006, Bone.

[27]  R. Rizzoli,et al.  Efficacy of risedronate on clinical vertebral fractures within six months , 2004, Current medical research and opinion.

[28]  T. Howe,et al.  Subtrochanteric insufficiency fractures in patients on alendronate therapy: a caution. , 2007, The Journal of bone and joint surgery. British volume.

[29]  P. Delmas,et al.  Bone quality--the material and structural basis of bone strength and fragility. , 2006, The New England journal of medicine.

[30]  D. Burr,et al.  Recovery of Trabecular and Cortical Bone Turnover After Discontinuation of Risedronate and Alendronate Therapy in Ovariectomized Rats , 2008, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[31]  G. Dalsky,et al.  Sustained Nonvertebral Fragility Fracture Risk Reduction After Discontinuation of Teriparatide Treatment , 2005, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[32]  J. Manson,et al.  Calcium plus vitamin D supplementation and the risk of fractures. , 2006, The New England journal of medicine.

[33]  A. Westfall,et al.  Risk of hip fracture after bisphosphonate discontinuation: implications for a drug holiday , 2008, Osteoporosis International.

[34]  E. Glass,et al.  Relationship between duration of teriparatide therapy and clinical outcomes in postmenopausal women with osteoporosis , 2009, Osteoporosis International.

[35]  P. Meunier,et al.  Changes in Bone Remodeling Rate Influence the Degree of Mineralization of Bone , 2002, Connective tissue research.

[36]  A. M. Parfitt,et al.  Skeletal Heterogeneity and the Purposes of Bone Remodeling: Implications for the Understanding of Osteoporosis , 2001 .

[37]  J. Cramer,et al.  Non-compliance: the Achilles' heel of anti-fracture efficacy , 2007, Osteoporosis International.

[38]  O. Johnell,et al.  The components of excess mortality after hip fracture. , 2003, Bone.

[39]  P. Croucher,et al.  The effects of gonadotrophin-releasing hormone agonists on iliac crest cancellous bone structure in women with endometriosis. , 1995, Bone.

[40]  P. Delmas,et al.  Treatment of postmenopausal osteoporosis , 2002, The Lancet.

[41]  P. Geusens,et al.  Relationship Between Changes in BMD and Nonvertebral Fracture Incidence Associated With Risedronate: Reduction in Risk of Nonvertebral Fracture Is Not Related to Change in BMD , 2005, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[42]  S. Rietbrock,et al.  Fracture Outcomes Related to Persistence and Compliance With Oral Bisphosphonates , 2008, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[43]  D. Wenkert,et al.  Bisphosphonate‐Induced Osteopetrosis: Novel Bone Modeling Defects, Metaphyseal Osteopenia, and Osteosclerosis Fractures After Drug Exposure Ceases , 2008, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[44]  G. H. Nancollas,et al.  Novel insights into actions of bisphosphonates on bone: differences in interactions with hydroxyapatite. , 2006, Bone.

[45]  S. Cummings,et al.  Effects of continuing or stopping alendronate after 5 years of treatment: the Fracture Intervention Trial Long-term Extension (FLEX): a randomized trial. , 2006, JAMA.

[46]  O. Akkus,et al.  Aging of Microstructural Compartments in Human Compact Bone , 2003, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[47]  Jacques P. Brown,et al.  Intravenous zoledronic acid in postmenopausal women with low bone mineral density. , 2002, The New England journal of medicine.

[48]  M. Hochberg,et al.  Treatment With Once‐Weekly Alendronate 70 mg Compared With Once‐Weekly Risedronate 35 mg in Women With Postmenopausal Osteoporosis: A Randomized Double‐Blind Study , 2004, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[49]  Michael C. Nevitt,et al.  Fracture Risk Reduction With Alendronate in Women With Osteoporosis: The Fracture Intervention Trial , 2001 .

[50]  T. Keaveny,et al.  A Biomechanical Analysis of the Effects of Resorption Cavities on Cancellous Bone Strength , 2006, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[51]  D. Wenkert,et al.  Bisphosphonate-induced osteopetrosis. , 2003, The New England journal of medicine.

[52]  I. Reid,et al.  Randomized controlled trial of calcium in healthy older women. , 2006, The American journal of medicine.

[53]  J. Reginster,et al.  Sustained vertebral fracture risk reduction after withdrawal of teriparatide in postmenopausal women with osteoporosis. , 2004, Archives of internal medicine.

[54]  M. Saito,et al.  Collagen maturity, glycation induced-pentosidine, and mineralization are increased following 3-year treatment with incadronate in dogs , 2008, Osteoporosis International.

[55]  J. Bilezikian Osteonecrosis of the jaw--do bisphosphonates pose a risk? , 2006, The New England journal of medicine.