Postmenopausal osteoporosis. What have we learned since the introduction of bisphosphonates?

EFFECT OF LOCALLY DELIVERED BISPHOSPHONATES ON ALVEOLAR BONE: A SYSTEMATIC REVIEW AND META-ANALYSIS

OBJECTIVE

To assess the effect of locally applied bisphosphonate drugs on alveolar bone defects caused by periodontitis and marginal bone level after placement of dental implants.

MATERIALS AND METHODS

Three electronic databases (PubMed/MEDLINE, Web of Science, and Scopus) were searched from January 2010 until May 2020 for randomized controlled clinical trials reporting the effect of locally delivered bisphosphonates on alveolar bone. The risk of bias was assessed and quantitative synthesis was conducted with both fixed and random-effects meta-analyses by using RevMan version 5.3. Subgroup and sensitivity analyses were performed whenever required.

RESULTS

Among the included studies, the effect of locally delivered bisphosphonates on alveolar bone regeneration in periodontitis was measured by 15 studies and on marginal bone level after installation of dental implants by three studies. Bisphosphonates showed significantly higher intrabony defect depth reduction than placebo/control in vertical bone defects treated with non-surgical approach (MD = 1.69mm; 95% CI, 1.32-2.05; P < 0.00001; I²=93%) or surgical approach (MD = 0.70mm; 95% CI, 0.23-1.16; P = 0.003; I² = 78%) and in class II furcation defects treated with non-surgical approach (MD = 1.61mm; 95% CI, 1.15-2.07; P < 0.00001; I² = 99%) or surgical approach (MD = 0.24mm; 95% CI, 0.05-0.42; P = 0.01; I² = 62%). Clinical attachment loss increased by 1.39mm (95% CI, 0.92-1.85; P < 0.01; I²=93%) and 1mm (95% CI, 0.75-1.26; P < 0.001; I² = 0%) in vertical bone defects after non-surgical and surgical treatments, respectively, and by 1.95mm (95% CI, 1.37-2.53; P < 0.00001; I² = 96%) and 0.84mm (95% CI, 0.58-1.10; P < 0.01, I² = 47%) after non-surgical and surgical treatment in class II furcation defects, respectively. Lesser marginal bone loss during pre-loading (MD = -0.18 mm; 95% CI, -0.24- -0.12; P<0.00001; I²=0%) and 1-year post-loading (MD = -0.33 mm; 95% CI, -0.59-0.07; P = 0.01; I² = 0%) periods was observed when bisphosphonate coated dental implants were used.

CONCLUSION

Locally delivered bisphosphonates induce bone regeneration in periodontal defects and decrease the rate of marginal bone loss after dental implant therapy.

Mandibular Osteonecrosis Associated With Raloxifene

Osteonecrosis is a disease with diverse pathophysiology, clinical presentation, and management. It may be associated with some medications used to treat systemic issues with bone metabolism. A few cases of jaw bone osteonecrosis have been associated with raloxifene. In this paper, the authors present a clinical report of a 64-year-old woman who presented with a necrosis foci in the right alveolar ridge of the mandible, associated with continued raloxifene use.

Vitamin D, osteoprotegerin/receptor activator of nuclear factor-kappaB ligand (OPG/RANKL) and inflammation with alendronate treatment in HIV-infected patients with reduced bone mineral density

OBJECTIVES

The aim of the study was to determine the effect of alendronate (ALN) on inflammatory markers and osteoprotegerin (OPG)/receptor activator of nuclear factor-kappaB ligand (RANKL), and to explore the associations of baseline systemic inflammation and vitamin D status on the bone mineral density (BMD) response to ALN.

METHODS

Eighty-two HIV-positive patients with lumbar spine T-score ≤ -1.5 were randomized to ALN 70 mg weekly or placebo for 48 weeks; all received calcium carbonate 500 mg/vitamin D3 200 IU twice daily. Serum C-telopeptide (CTx) and BMD were assessed at baseline and week 48. Stored plasma samples in 70 subjects were assayed for levels of 25-hydroxyvitamin D (25(OH)D), OPG, RANKL, interleukin (IL)-6 and soluble receptors for tumour necrosis factor (TNF)-α 1 and 2 (sTNFR 1 and 2).

RESULTS

ALN increased BMD more than placebo at both the lumbar spine (difference ALN - placebo 2.64%; P = 0.011) and the total hip (difference 2.27%; P = 0.016). No within- or between-arm differences in OPG, RANKL or inflammatory markers were observed over 48 weeks. High baseline CTx and sTNFR2 were associated with a more robust BMD response to ALN over 48 weeks at the lumbar spine [difference 5.66%; 95% confidence interval (CI) 3.50, 7.82; P < 0.0001] and total hip (difference 4.99%; 95% CI 2.40, 7.57; P = 0.0002), respectively. Baseline 25(OH)D < 32 ng/mL was associated with larger increases in total hip BMD over 48 weeks, independent of ALN treatment (P = 0.014).

CONCLUSIONS

Among HIV-positive patients, higher baseline bone resorption and TNF-α activity were associated with an increased BMD response to ALN. The greater BMD response in those with lower vitamin D reinforces the importance of vitamin D supplementation with bisphosphonate treatment.

Safety of drugs used in the treatment of osteoporosis

A number of drug classes are licensed for the treatment of osteoporosis including bisphosphonates, recombinant human parathyroid hormone (PTH), strontium, hormone replacement therapy (HRT), selective oestrogen receptor modulators (SERMS) and denosumab. This review discusses the safety of osteoporosis treatments and their efficacies. Recent concerns about the safety of calcium and high-dose vitamin D are discussed. Bisphosphonates have substantial postmarketing experience and a clearer picture of safety issues is emerging. Along with the well recognized effects on the gastrointestinal tract and kidney function, recently described adverse effects such as osteonecrosis of the jaw, oesophageal cancer, atrial fibrillation, subtrochanteric femur fractures and ocular complications of bisphosphonate therapy are discussed. Therapy with PTH is limited to two years' duration because of the development of osteogenic sarcomas in animal studies, which appeared related to dose, duration and timing of therapy. Strontium should be used with caution in patients with renal impairment and its use has been associated with venous thromboembolism. The role of HRT and SERMs in the treatment of postmenopausal osteoporosis is restricted as a result of an increased risk of stroke, venous thromboembolism and breast cancer. Postmarketing experience with denusomab is limited but a number of potential safety concerns including osteonecrosis of the jaw are emerging. All of these drugs have been proven to reduce fractures. The decision to use a drug to reduce fracture risk should be based on risk-benefit analysis of the drug and its suitability for individual patients.

[Biphosphonate-induced femoral stress fractures : A new problem and knowledge so far - case report]

During the last several years the treatment of osteoporosis with bisphosphonates has become accepted as a safe and effective procedure. However, recently there have been increasing numbers of reports of rare complications in the literature. Particularly the occurrence of atypical fractures of the femur has become a focus of interest but the problem is insufficiently known and only rarely addressed in the scientific discussion. The case illustrated here and a survey of the important facts in the recent literature highlight essential aspects of long-term bisphosphonate therapy.

Serum ionic fluoride concentrations are significantly decreased after treatment with alendronate in patients with osteoporosis

BACKGROUND

We determined serum ionic fluoride (SIF) concentrations before and after treatment of osteoporosis with alendronate to clarify whether SIF concentrations directly reflect a change in bone metabolism.

METHODS

A total of 45 postmenopausal women with primary osteoporosis who were treated with alendronate over a 6-month period were enrolled (mean age, 64.2 years). SIF concentrations were measured by the flow injection method with an ion-selective electrode. Concentrations of bone turnover markers (serum bone alkaline phosphatase, serum osteocalcin, serum type I collagen cross-linked N-telopeptide and urinary deoxypryridinoline) and lumbar spine BMD (LsBMD) were also measured. SIF, bone turnover markers and LsBMD before and after treatment were compared.

RESULTS

Concentrations of SIF as well as concentrations of all bone turnover markers were significantly decreased after treatment: means (standard deviations) before and after treatment were 0.62 (0.13) and 0.32 (0.09) μmol/l, respectively (P<0.001) and the percent change was -46.3%. LsBMD was also significantly increased by 6.7% after treatment.

CONCLUSIONS

The reduction of SIF concentrations is probably caused by inhibition of bone resorption due to the action of alendronate. The findings suggest that SIF concentrations directly reflect a change in bone metabolism.

Role of bisphosphonates in the management of postmenopausal osteoporosis: an update on recent safety anxieties

Following their introduction in the 1990s, bisphosphonates have become the mainstay of treatment in the management of postmenopausal osteoporosis, and their use continues to rise. Commonly noted adverse effects in clinical practice include gastrointestinal side-effects, acute phase reactions (predominately seen with intravenous preparations) cutaneous reactions and more rarely, ocular side-effects. However, recent reports of potentially serious adverse effects of bisphosphonate therapy, including atypical subtrochanteric and femoral shaft fractures, atrial fibrillation, oesophageal carcinoma and osteonecrosis of the jaw, have prompted concerns regarding the long-term safety of this class of drugs. This review summarizes the benefits and potential adverse effects of bisphosphonates used in the treatment of postmenopausal osteoporosis. Although evidence of a definitive casual relationship between bisphosphonate therapy and serious adverse effects is lacking, concern remains particularly in relation to atypical subtrochanteric and femoral shaft fractures. This has important consequences in terms of determining optimum duration of therapy and how best to target therapy at those most at risk. Recently, attention has focused on individual fracture risk assessment in order to optimize the risk-benefit ratio of treatment for individual patients. A review of the role of hormone replacement therapy in younger women with significant risk of osteoporotic fractures may be timely in these circumstances.

Influence of bisphosphonates on alveolar bone density: a histomorphometric analysis

This study is a histomorphometrical analysis of the influence of the bisphosphonate alendronate on alveolar bone density. Eighteen male Wistar rats were randomly assigned to a control group (n = 9) that received no medication and an experimental group (n = 9) that received oral alendronate (1 mg/kg) from birth until euthanization at 3 months of age. Semi-serial 4-µm-thick transverse sections were obtained from the region between the roots of the left maxillary first molar, stained with hematoxylin and eosin, and examined with a Zeiss Axioskop II optical microscope for histomorphometric analysis. The images were captured with a digital camera coupled with the microscope and connected to a computer, and were analyzed using Image J 1.34s image-analysis software. A 1,200-point grid was positioned onto each digitized image. The number of intersection points of grid lines in the bone tissue was counted. The ratio between the number of points in the bone tissue and the total number of points of the grid (1,200) was used to determine the bone density of the analyzed tissue. Data from the control and experimental groups were compared and analyzed statistically by the Student's t-test (p = 0.05). There was no statistically significant difference (p = 0.3754) in the alveolar bone density between the control and alendronate-treated animals. It may be concluded that the bisphosphonate alendronate did not alter the morphology of the alveolar bone, maintaining its structural tissue characteristics in healthy animals.

Cancer treatment-induced bone loss in breast and prostate cancer

PURPOSE

Bone loss resulting from the treatment of breast and prostate cancer is an emerging problem. Bisphosphonates have a potential role in the prevention of this cancer treatment-induced bone loss (CTIBL).

METHODS

Studies evaluating the incidence and prevalence of CTIBL in early breast and prostate cancer patients and trials evaluating the preventative role of bisphosphonates were identified by a search of the PubMed and Cochrane Library databases through the end of March 2008. Reference lists from retrieved articles were cross referenced, and further information was obtained from relevant scientific meetings.

RESULTS

Several therapies commonly used in the treatment of women and men with breast and prostate cancers, in particular the aromatase inhibitors (AIs) for breast cancer and androgen deprivation therapy (ADT) for prostate cancer, are associated with significant bone loss and with an increase in fracture risk. The use of bisphosphonates seems to attenuate the bone loss, although the long-term impact remains unclear because of insufficient follow-up.

CONCLUSION

Adjuvant endocrine therapy with an AI or androgen deprivation can be considered a risk factor for the development of osteopenia, osteoporosis, and bone fracture, which can be mitigated by appropriate bisphosphonate therapy. Clear identification of risk factors for osteoporosis in individual patients should aid treatment decisions about whether to use bisphosphonates when starting or switching to an AI or ADT. Patients need to be educated about this risk and other measures to avoid this complication, including lifestyle modifications that may benefit their general and bone health.