Osteoporosis Treatment: When to Discontinue and When to Re-start

Aucubin produces anti-osteoporotic effects under mechanical stretch stress and orthodontic tooth movement

Aucubin (AU), an iridoid glycoside extracted from Eucommia ulmoides, exerts anti-osteoporotic effects by promoting osteogenesis, as reported in previous studies. Here, we investigated the effects of AU under mechanical stretch stress. MC3T3-E1 cells were treated with dexamethasone (DEX) in vitro and subjected to mechanical stretch stress to establish an osteoporotic orthodontic force cell model. AU treatment increased the mRNA and protein expressions of BMP2, OPN, RUNX2, COL-1 and other osteogenic differentiation factors in MC3T3-E1 cells. Furthermore, we established an in vivo orthodontic tooth movement (OTM) model of osteoporosis. Serum parameter detection of ALP concentration, radiography of the femur, hematoxylin-eosin (HE) staining, and micro-CT of the maxilla confirmed that AU could partially reverse the damage induced by DEX. Immunohistochemical (IHC) analysis showed that AU increased the expression of COL-1, OCN, and OPN on the tension side of the periodontium. In conclusion, AU treatment promotes osteogenic differentiation under mechanical stretch stress and positively affects bone remodeling during OTM in DEX-induced osteoporosis.

Anti-resorptive therapy in the osteometabolic patient affected by periodontitis. A joint position paper of the Italian Society of Orthopaedics and Traumatology (SIOT) and the Italian Society of Periodontology and Implantology (SIdP)

This joint report from the Italian Society of Orthopaedics and Traumatology (SIOT) and the Italian Society of Periodontology and Implantology (SIdP) aims for a consensus around the scientific rationale and clinical strategy for the management of osteoporotic patients affected by periodontitis who are undergoing anti-resorptive (AR) therapy to manage the risk of the occurrence of a medication-related osteonecrosis of the jaws (MRONJ). Osteoporosis and periodontitis are chronic diseases with a high prevalence in aging patients, and they share some of the same pathogenetic mechanisms based upon inflammation. Available evidence shows the relationship among osteoporosis, AR agents, periodontitis and implant therapy in relation to the incidence of MRONJ. Uncontrolled periodontitis may lead to tooth loss and to the need to replace teeth with dental implants. Tooth extraction and surgical dental procedures are recognized as the main risk factors for developing MRONJ in individuals taking AR therapy for osteometabolic conditions. Although the incidence of MRONJ in osteometabolic patients taking AR therapy may be as low as 0.9%, the increasing prevalence of osteoporosis and the high prevalence of periodontitis suggest that this potential complication should not be overlooked. Good clinical practice (GCP) guidelines are proposed that aim at a more integrated approach (prescriber, dentist, periodontist and dental hygienist) in the management of periodontitis patients undergoing AR therapy for osteometabolic disorders to reduce the risk of MRONJ. Dental professional and prescribers should educate patients regarding the potential risk associated with the long-term use of AR therapy and oral health behavior.

Advances in Osteoporotic Bone Tissue Engineering

The increase in osteoporotic fracture worldwide is urging bone tissue engineering research to find new, improved solutions both for the biomaterials used in designing bone scaffolds and the anti-osteoporotic agents capable of promoting bone regeneration. This review aims to report on the latest advances in biomaterials by discussing the types of biomaterials and their properties, with a special emphasis on polymer-ceramic composites. The use of hydroxyapatite in combination with natural/synthetic polymers can take advantage of each of their components properties and has a great potential in bone tissue engineering, in general. A comparison between the benefits and potential limitations of different scaffold fabrication methods lead to a raised awareness of the challenges research face in dealing with osteoporotic fracture. Advances in 3D printing techniques are providing the ways to manufacture improved, complex, and specialized 3D scaffolds, capable of delivering therapeutic factors directly at the osteoporotic skeletal defect site with predefined rate which is essential in order to optimize the osteointegration/healing rate. Among these factors, strontium has the potential to increase osseointegration, osteogenesis, and healing rate. Strontium ranelate as well as other biological active agents are known to be effective in treating osteoporosis due to both anti-resorptive and anabolic properties but has adverse effects that can be reduced/avoided by local release from biomaterials. In this manner, incorporation of these agents in polymer-ceramic composites bone scaffolds can have significant clinical applications for the recovery of fractured osteoporotic bones limiting or removing the risks associated with systemic administration.

Osteoporosis in Older Persons: Old and New Players

Osteoporosis is the most common bone disease in humans. Older persons are at higher risk of osteoporotic fractures that also result in poor quality of life, disability, loss of independence, institutionalization, and higher mortality. Osteoporosis shares a distinct pathophysiologic relationship with sarcopenia, an age-related disease comprising declines in muscle mass, strength, or function. The combination of these two diseases is known as osteosarcopenia. Understanding the pathophysiology of osteosarcopenia, in addition to its diagnostic and therapeutic approaches, is key in providing older adults with the best falls and fractures prevention strategies. This review provides updated information on new discoveries on the combined pathophysiology of osteoporosis and sarcopenia that have led to the development of novel therapeutic approaches. New recommendations for the use of risk calculators and densitometry are also presented in this review as well as evidence on current and upcoming pharmacologic treatments to prevent falls and fractures in older persons. J Am Geriatr Soc 67:831-840, 2019.

Multiple Vertebral Osteonecroses (Kümmell's Disease) After 10 Years on Denosumab: Is Osteocyte Apoptosis to Blame?

We report here a case of multiple vertebral osteonecroses with intrasomatic gaseous dissection (Kümmell's disease) occurring 1 year after the end of a 10-year course of denosumab treatment for osteoporosis without fractures. Histomorphometry and bone remodeling markers revealed major bone resorption and the persistence of an inhibition of bone formation. The presence of multiple empty lacunae in the bone provided evidence for high levels of osteocyte apoptosis. Osteocytes direct bone resorption (via the RANK/RANK-L/osteoprotegerin system) and formation (Wnt system, with SOST and DKK1) pathways. The vertebral osteonecrosis in our case may, therefore, have resulted from osteocyte apoptosis, decompensated by the sudden reactivation of bone remodeling after the cessation of denosumab treatment.

Fructus Ligustri Lucidi ethanol extract inhibits osteoclastogenesis in RAW264.7 cells via the RANKL signaling pathway

Fructus ligustri Lucidi (FLL) is the fruit of Ligustrum lucidum Ait and a traditional Chinese medicine, primarily known for its role in osteoporosis prevention and treatment. The present study aimed to elucidate the effect and underlying mechanism of action of ethanol extract of FLL on osteoclast differentiation and bone resorption, and to identify the active compounds within it. RAW264.7 murine monocyte/macrophage cells were stimulated with the receptor activator of nuclear factor κB ligand (RANKL) to induce osteoclast differentiation in vitro. The present study demosntrated that FLL extract and its two primary components, oleanolic acid (OA) and ursolic acid (UA), significantly suppressed RANKL‑induced tartrate resistant acid phosphatase (TRAP) activity and multinucleate osteoclast formation without inducing cytotoxicity; however, no effect was observed on the apoptosis of mature osteoclasts. Additionally, RANKL‑induced mRNA expression levels of the key transcription factors, tumor necrosis factor receptor associated factor‑6, nuclear factor of activated T cell‑c1 and c‑Fos, and the osteoclast markers, TRAP, cathepsin K and matrix metalloproteinase‑9 were suppressed by FLL, OA and UA. However, no effect was observed on RANKL‑induced mRNA expression levels of Src. These results demonstrated that FLL may inhibit osteoclastogenesis in RAW264.7 cells via RANKL signaling pathways. OA and UA are active compounds in inducing this effect; however, their specific roles remain to be elucidated.

GRAND-4: the German retrospective analysis of long-term persistence in women with osteoporosis treated with bisphosphonates or denosumab

This retrospective database study assessed 2-year persistence with bisphosphonates or denosumab in a large German cohort of women with a first-time prescription for osteoporosis treatment. Compared with intravenous or oral bisphosphonates, 2-year persistence was 1.5-2 times higher and risk of discontinuation was significantly lower (P < 0.0001) with denosumab.

INTRODUCTION

Persistence with osteoporosis therapies is critical for fracture risk reduction. Detailed data on long-term persistence (≥2 years) with bisphosphonates and denosumab are sparse.

METHODS

From the German IMS® database, we included women aged 40 years or older with a first-time prescription for bisphosphonates or denosumab between July 2010 and August 2014; patients were followed up until December 2014. The main outcome was treatment discontinuation, with a 60-day permissible gap between filled prescriptions. Two-year persistence was estimated using Kaplan-Meier survival curves, with treatment discontinuation as the failure event. Denosumab was compared with intravenous (i.v.) and oral bisphosphonates separately. Cox proportional hazard ratios (HRs) for the 2-year risk of discontinuation were calculated, with adjustment for age, physician specialty, health insurance status, and previous medication use.

RESULTS

Two-year persistence with denosumab was significantly higher than with i.v. or oral bisphosphonates (39.8 % [n = 21,154] vs 20.9 % [i.v. ibandronate; n = 20,472] and 24.8 % [i.v. zoledronic acid; n = 3966] and 16.7-17.5 % [oral bisphosphonates; n = 114,401]; all P < 0.001). Patients receiving i.v. ibandronate, i.v. zoledronic acid, or oral bisphosphonates had a significantly increased risk of treatment discontinuation than did those receiving denosumab (HR = 1.65, 1.28, and 1.96-2.02, respectively; all P < 0.0001).

CONCLUSIONS

Two-year persistence with denosumab was 1.5-2 times higher than with i.v. or oral bisphosphonates, and risk of discontinuation was significantly lower with denosumab than with bisphosphonates. A more detailed understanding of factors affecting medication-taking behavior may improve persistence and thereby reduce rates of fracture.

Pharmacological management of osteoporosis - when to treat and when to stop

INTRODUCTION

Bisphosphonates are antiresorptive drugs of proven efficacy which are widely used for osteoporosis. After stopping bisphosphonate therapy, residual therapeutic effects persist for an undefined period; thus, some osteoporotic patients could benefit from a temporary discontinuation, the so called 'drug holiday'. Areas covered: We reviewed the effects of discontinuing various anti-fracture treatments in order to clarify both clinical features of patients for whom a drug holiday from an initial bisphosphonate treatment period could be offered and a possible approach to the management of the drug holiday. A PubMed search was undertaken using the following main search terms: 'bisphosphonates', 'drug holiday', 'treatment discontinuation', 'anti-fracture drugs'. Expert commentary: After an initial bisphosphonate treatment period of 3-5 years, fracture risk should be reassessed in order to decide if a drug holiday could be offered to patients. Those at high fracture risk should continue treatment; those at moderate-mild fracture risk could temporarily discontinue treatment.

The use of bisphosphonates in women: when to use and when to stop

INTRODUCTION

Bisphosphonates (BPs) are the most commonly used drugs in osteoporosis.

AREAS COVERED

This review focuses on the criteria for identifying patients who should be treated with BPs and also the rational for the duration of treatment.

EXPERT OPINION

BPs remain the mainstay for the treatment of osteoporosis. For their low cost, the treatment threshold is related exclusively to the ratio between expected benefits and the risk of side effects. This is the case of patients with prior fragility fracture or with low bone density and the presence of other relevant risk factors. The treatment should continue for 3 - 5 years or until fracture risk is no longer high. Afterward a treatment holiday should be considered on the light of the increasing risk of side effects but its duration is still controversial. The duration of this treatment holiday depends on the drug used. Discontinuation of risedronate and ibandronate is associated with the quick loss of the acquired benefits and with these two BPs discontinuation should not exceed 6 months. Alendronate and zoledronate are characterized by a persistent effect after discontinuing treatment and this would allow a more prolonged drug holiday.