Interleukin-6 and tumor necrosis factor alpha levels after bisphosphonates treatment in vitro and in patients with malignancy

Significance of medication discontinuation on bisphosphonate-related jaw osteonecrosis in a rat model

Bisphosphonate (BP) discontinuation has been advised as a measure to prevent the incidence of bisphosphonate-related osteonecrosis of the jaw (BRONJ), however, its efficacy remains controversial. This study aimed to analyze the efficacy of BP discontinuation in reducing BRONJ severity following tooth extraction in a rat model. Thirty-four male Sprague-Dawley rats were divided into two BRONJ model categories: oral administration (PO) of alendronate (1 mg/kg) for 3 and 8 weeks and intraperitoneal (IP) injection of pamidronate (3 mg/kg) and dexamethasone (1 mg/kg) for 20 days. The PO model was divided into five groups (a control group without BPs and four experimental groups with 1-week discontinuation). The IP model was divided into two groups consisting of group I (without discontinuation) and group II (1-week discontinuation). One molar from both sides of the mandible was extracted. After extraction, the PO models were sacrificed at 3 and 5 weeks, and the IP models were sacrificed either immediately or at 2, 4, 6, and 8 weeks. Micro-CT showed non-significant differences among PO groups but significant differences were observed between IP groups. Most bone remodeling parameters within group I of the IP model differed significantly (p-value < 0.05). Histologically, group I showed a significantly higher percentage of necrotic bone than group II (51.93 ± 12.75%, p < 0.05) and a higher number of detached osteoclasts in TRAP staining. With discontinuation of medication for at least 1 week in rats, the effects of BPs on alveolar bone are suppressed and bone turnover and osteoclast functions are restored.

Predicting the acute-phase response fever risk in bisphosphonate-naive osteoporotic patients receiving their first dose of zoledronate

INTRODUCTION

To devise a precise and efficient tool for predicting the individualized risk of acute-phase response (APR) in bisphosphonate (BP)-naive osteoporotic (OP) patients, receiving their first intravenous dose of zoledronate (ZOL).

METHODS

The baseline clinical and laboratory data of 475 consecutive BP-naive OP patients, who received their first intravenous dose of ZOL between March 2016 and March 2021 in the Affiliated Kunshan Hospital of Jiangsu University, were chosen for analysis. Univariate and multivariable logistic regression models were generated to establish candidate predictors of APR fever risk, using three distinct fever thresholds, namely, 37.3 °C (model A), 38.0 °C (model B), and 38.5 °C (model C). Next, using predictor regression coefficients, three fever-threshold nomograms were developed. Discrimination, calibration, and clinical usefulness of each predicting models were then assessed using the area under the curve (AUC), calibration curve (CC), and decision curve analysis (DCA). The internal and external model validations were then performed.

RESULTS

The stable predictors were age, serum 25-hydroxy vitamin D, serum total calcium, and peripheral blood erythrocytes count. These were negatively associated with the APR fever risk. The AUCs of models A, B, and C were 0.828 (95% confidence intervals [CI], 0.782 to 0.874), 0.825 (95% CI, 0.767 to 0.883), and 0.879 (95% CI, 0.824 to 0.934), respectively. Good agreement was observed between the predictions and observations in the CCs of all three nomograms.

CONCLUSIONS

This study developed and validated nomogram prediction models that can predict APR fever risk in BP-naive OP patients receiving their first infusion of ZOL.

Bisphosphonates Related Ocular Side Effects: A Case Series and Review of Literature

OBJECTIVE

To describe the clinical features of patients with bisphosphonate related ocular side effects (BROSE).

METHODS

The medical records of all patients with BROSE between January 2009 and December 2019 were reviewed.

RESULTS

Nine cases with BROSE were identified. All subjects were female. Median age at diagnosis was of 69 years. The leading indication for bisphosphonate treatment was osteoporosis (n=7), Paget's disease of bone (n=1) and breast cancer (n=1). Six (66.67%) patients presented with uveitis, one (11%) episcleritis and two (22%) with orbital inflammation. Five events (55.5%) occurred within 10 days of initiating the bisphosphonate and the rest (44.44%) developed within 2 weeks to 3 years later. Four (44.44%) patients had concurrent thyroid disease. An association was found between underlying thyroid disease or autoimmunity.

CONCLUSION

BROSE is an uncommon complication of bisphosphonate therapy occurring more frequently in patients with an autoimmune predisposition.

Osteoporosis, bisphosphonates, and ocular inflammation

BACKGROUND

Osteoporosis, as a musculoskeletal disease, is very common, especially in the era of aging society. It is described by a reduction in bone strength and increased risk of fractures, which are linked to considerable morbidity, mortality, and high healthcare burdens. Bisphosphonates are the most commonly used drugs to manage osteoporosis and they consequently reduce fracture risk. However, one of the clinical challenges is fear of side effects in patients who are using bisphosphonates as the administration of these drugs is lengthy. Ocular inflammation has been reporting as one of the potential vision-threatening side effects of bisphosphonates.

PURPOSE

To review previously reported ocular inflammation in patients taking bisphosphonates.

METHOD

A literature survey was conducted using databases in order to collect data for a narrative review of published reports regarding ocular side effects of bisphosphonates.

RESULTS

People taking bisphosphonates were at a relatively low risk of ocular inflammation, with the onset from a few hours after exposure up to more than 3 years. The release of inflammatory mediators mainly by activated gamma delta T cells in response to bisphosphonates was the main cause of ocular inflammation.

CONCLUSION

Strategies for treating patients with osteoporosis should consider the potential ocular side effects of bisphosphonates. Ocular inflammation, as one of the side effects of bisphosphonates, is a serious sight-threatening sign and should be taken seriously. Greater awareness of the association between bisphosphonate use and ocular inflammation may allow for earlier identification and timely treatment of future cases.

Association between vitamin D and zoledronate-induced acute-phase response fever risk in osteoporotic patients

OBJECTIVES

To elucidate the independent correlation between vitamin D content and zoledronate (ZOL)-triggered acute-phase response (APR) fever risk in osteoporotic (OP) patients, and to examine the potential threshold for optimal vitamin D concentrations that prevent the occurrence of ZOL-induced fever.

METHODS

This retrospective investigation was based on a prospectively documented database compiled at the Affiliated Kunshan Hospital of Jiangsu University between January 2015 and March 2022. In total, 2095 OP patients, who received ZOL during hospitalization, were selected for analysis. The primary endpoint was the presence (>37.3°C) or absence (≤37.3°C) of fever, quantified by the maximum body temperature, measured within 3 days of ZOL infusion. The exposure variable was the baseline serum 25-hydroxyvitamin D (25[OH]D) levels.

RESULTS

The OP patients with fever exhibited markedly reduced 25(OH)D content than those without fever. Upon adjusting for age, gender, order of infusion of ZOL, main diagnosis, season of blood collection, year of blood collection, calcitonin usage, and beta-C-terminal telopeptide of type I collagen (β-CTX) levels, a 10 ng/mL rise in serum 25(OH)D content was correlated with a 14% (OR, 0.86; 95% CI, 0.76 to 0.98, P-value = 0.0188) decrease in the odds of ZOL-induced fever. In addition, a non-linear relationship was also observed between 25(OH)D levels and fever risk, and the turning point of the adjusted smoothed curve was 35 ng/mL of serum 25(OH)D content.

CONCLUSIONS

Herein, we demonstrated the independent negative relationship between serum 25(OH)D content and ZOL-induced fever risk. According to our analysis, 25(OH)D above 35 ng/mL may be more effective in preventing ZOL-induced APR. If this is confirmed, a "vitamin D supplemental period" is warranted prior to ZOL infusion, particularly the first ZOL infusion, to ensure appropriate 25(OH)D levels that protect against ZOL-induced fever.

Pediatric uveitis: Role of the pediatrician

The challenges of childhood uveitis lie in the varied spectrum of its clinical presentation, the often asymptomatic nature of disease, and the evolving nature of the phenotype alongside normal physiological development. These issues can lead to delayed diagnosis which can cause significant morbidity and severe visual impairment. The most common ocular complications include cataracts, band keratopathy, glaucoma, and macular oedema, and the various associated systemic disorders can also result in extra-ophthalmic morbidity. Pediatricians have an important role to play. Their awareness of the various presentations and etiologies of uveitis in children afford the opportunity of prompt diagnosis before complications arise. Juvenile Idiopathic Arthritis (JIA) is one of the most common associated disorders seen in childhood uveitis, but there is a need to recognize other causes. In this review, different causes of uveitis are explored, including infections, autoimmune and autoinflammatory disease. As treatment is often informed by etiology, pediatricians can ensure early ophthalmological referral for children with inflammatory disease at risk of uveitis and can support management decisions for children with uveitis and possible underling multi-system inflammatory disease, thus reducing the risk of the development of irreversible sequelae.

Effect of Human Umbilical Cord Matrix-Derived Mesenchymal Stem Cells on Bisphosphonate-Related Osteonecrosis of the Jaw

BACKGROUND

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a severe sequela caused by bisphosphonates (BPs), which are widely used to treat osteoporosis or other malignancies. However, the mechanism underlying BRONJ remains unclear. Recently, human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) have been studied for treatment of diverse diseases and injuries. This study aimed to investigate the therapeutic effects of hUC-MSCs in BRONJ.

METHODS

The therapeutic effects of hUC-MSCs were examined in rat bone marrow (rBM)-derived cells using cell viability, colony-forming, and real-time PCR assays and FACS for analyzing essential proinflammatory and bone regeneration markers in vitro. To demonstrate the in vivo therapeutic and adverse effects of transfused hUC-MSCs, micro-CT, H&E staining, IHC (Angiogenesis marker gene expression) staining, and parathyroid hormone (PTH)/calcium assay were conducted in a BRONJ-induced animal model.

RESULTS

BP-induced cytotoxicity and inflammation in rBM-derived cells decreased, after co-culture with hUC-MSCs. The expression levels of bone regeneration markers (RUNX2, OSX, and BMP-2) significantly increased in BP-treated rBM-derived cells, after co-culture with hUC-MSCs. The BP-induced abnormal shift in RANKL/OPG expression ratio in rBM-derived cells was normalized by hUC-MSCs. Consistent with these in vitro results, transfused hUC-MSCs markedly decreased BRONJ and significantly healed injured mucosa in the BRONJ-induced animal model. The animals exhibited serious destruction of the kidney structure and increases in serum PTH and calcium levels, which were significantly normalized by hUC-MSC transfusion.

CONCLUSION

hUC-MSCs exerted therapeutic effects on BRONJ in vitro and in vivo through their anti-cytotoxicity, anti-inflammatory activity and ability to recover bone regeneration.

Human Serum Enhances Biomimicry of Engineered Tissue Models of Bone and Cancer

For decades, fetal bovine serum (FBS) has been used routinely for culturing many cell types, based on its empirically demonstrated effects on cell growth, and the lack of suitable non-xenogeneic alternatives. The FBS-based culture media do not represent the human physiological conditions, and can compromise biomimicry of preclinical models. To recapitulate in vitro the features of human bone and bone cancer, we investigated the effects of human serum and human platelet lysate on modeling osteogenesis, osteoclastogenesis, and bone cancer in two-dimensional (2D) and three-dimensional (3D) settings. For monitoring tumor growth within tissue-engineered bone in a non-destructive fashion, we generated cancer cell lines expressing and secreting luciferase. Culture media containing human serum enhanced osteogenesis and osteoclasts differentiation, and provided a more realistic in vitro mimic of human cancer cell proliferation. When human serum was used for building 3D engineered bone, the tissue recapitulated bone homeostasis and response to bisphosphonates observed in native bone. We found disparities in cell behavior and drug responses between the metastatic and primary cancer cells cultured in the bone niche, with the effectiveness of bisphosphonates observed only in metastatic models. Overall, these data support the utility of human serum for bioengineering of bone and bone cancers.

Drug-induced uveitis: A review

Uveitis maybe induced by the use of various medications known as drug-induced uveitis (DIU), though rare it is an important cause of uveitis which one needs to be aware of. The drugs may be administered through any route including systemic, topical, and intravitreal. Ocular inflammation can be in the form of anterior, intermediate, posterior or pan uveitis, and rarely may present as episcleritis and scleritis. Identification of drug as the offending agent of uveitis is important as many a times stopping the drug may help recover the uveitis or the concomitant use of corticosteroids. An extensive literature review was done using the Pubmed. An overview of DIU is provided as it is important for us to be aware of this clinical entity.

Zoledronate promotes inflammatory cytokine expression in human CD14-positive monocytes among peripheral mononuclear cells in the presence of γδ T cells

Bisphosphonates distributed to bone exert toxic effects specifically towards osteoclasts. On the other hand, intravenous administration of a nitrogen-containing bisphosphonate (N-BP) such as zoledronate induces acute-phase reactions (APRs), including influenza-like fever 1 day later, indicating an interaction with immunocompetent cells circulating blood. Although it has been reported that activation of γδ T cells is pivotal to induce an APR following treatment with zoledronate, downstream events, including the production of inflammatory cytokines after activation of γδ T cells, remain obscure. We investigated the effects of zoledronate on inflammatory cytokine expression in human peripheral blood mononuclear cells (PBMCs) in vitro. While zoledronate induced mRNA expressions of tumour necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6 and interferon-γ (IFN-γ) in PBMC, depletion of γδ T cells abolished that zoledronate-induced expression of those cytokines, indicating the necessity of γδ T cells for expression induction by zoledronate. However, which types of cells were responsible for the production of those cytokines in blood remained unclear. As it is generally accepted that monocytes and macrophages are primary sources of inflammatory cytokines, CD14⁺ cells from PBMC were exposed to zoledronate in the presence of PBMC, which resulted in induced expression of mRNAs for IL-1β, IL-6 and IFN-γ, but not for TNF-α. These results indicate that CD14⁺ cells are responsible, at least in part, for the production of IL-1β, IL-6 and IFN-γ in blood exposed to zoledronate. This suggests that CD14⁺ cells play an essential role in the occurrence of APRs following N-BP administration.

Acute unilateral anterior uveitis following zoledronic acid infusion: A case report

Bisphosphonates are widely used to treat several clinical conditions. Zoledronic acid is one of this class, commonly used for the treatment and prevention of osteoporosis, hypercalcemia of malignancy, Paget's disease, and multiple myeloma. A variety of ocular side effects associated with bisphosphonates therapy has been reported but are uncommon and readily treatable. Most of these ocular inflammatory conditions are associated with other bisphosphonates such as pamidronate but rarely reported with zoledronic acid. Acute anterior uveitis associated with zoledronic acid is rare. We describe a 75-year-old female who presented with features of acute unilateral non-granulomatous anterior uveitis which developed within 24 h following the first dose of intravenous infusion of zoledronic acid administered to treat post-menopausal osteoporosis. She was treated with topical steroids and made an uneventful recovery in 2 weeks.

Pamidronate: A model compound of the pharmacology of nitrogen-containing bisphosphonates; A Leiden historical perspective

Pamidronate [3-amino-1-hydroxypropylidene-1,1-bisphosphonate (APD)] was the first nitrogen-containing bisphosphonate (N-BP) investigated in clinical studies. In contrast to other clinically used bisphosphonates, pamidronate was discovered and its properties were initially studied in an Academic Institution. On the occasion of the 50th Anniversary of the first publications on the biological effects of bisphosphonates, I review in this article the contribution of Leiden investigators to the development of pamidronate that led to the recognition of the significance of the Nitrogen atom in the side chain of bisphosphonates for their action on bone resorption and to the formulation of principles for the use of N-BPs in the management of patients with different skeletal disorders.

The Effect of Zoledronic Acid on Serum Biomarkers among Patients with Chronic Low Back Pain and Modic Changes in Lumbar Magnetic Resonance Imaging

The aim of the current study was to compare changes in serum biomarkers, including inflammatory mediators, signaling molecules, growth factors and markers of bone turnover after a single intravenous infusion of 5 mg zoledronic acid (ZA, a long-acting bisphosphonate; n = 20) or placebo (n = 20) among patients with Modic changes (MC) and chronic low back pain in a randomized controlled design. The MCs were classified into M1, predominating M1, predominating M2, and M2. We measured the serum concentrations of 39 biomarkers at baseline, and one month and one year after treatment. After Benjamini–Hochberg (B–H) correction, we observed significant differences in three biomarkers over one year: Interferon-γ-inducible protein (IP-10) had risen in the ZA group (p = 0.005), whereas alkaline phosphatase (AFOS) and intact procollagen I N-terminal propeptide (iPINP) had significantly decreased in the ZA group, but had not changed in the placebo group (p < 0.001 for both). Change in iPINP correlated with change in the volume of all MC and M1 lesions. ZA downregulated bone turnover markers as expected and, surprisingly, increased the chemokine IP-10 relative to placebo treatment. This adds to our knowledge of the effects of ZA on MC and the biomarkers that signal this process.

Alendronate induced chorioretinitis: The importance of meticulous assessments

Purpose

To report a case of presumed bilateral chorioretinitis secondary to alendronate therapy.

Observations

A 71-year-old female presented to the clinic in July 2017 with six months history of difficulty in reading along with floaters in both eyes which were more severe in the right eye. Past medical and surgical history revealed a history of hypertension, gout, hyperthyroidism, osteoporosis, and humerus fracture. She was started on alendronate three months before developing ocular symptoms. On ocular examination, best corrected visual acuity was 20/30 in the right and 20/25 in the left eye. Slit-lamp examination demonstrated normal anterior chamber examination in both eyes. Dilated fundus examination revealed geographic chorioretinal lesions around the optic nerve head in both eyes, more extensively in the right eye; and superior and temporal to the macula in the right eye. Past ocular records in February 2015 did not reveal any such findings. Fundus autofluorescence demonstrated hyper-autofluorescence in the peripapillary lesions in both eyes. The lesion adjacent to the macula in right eye displayed mixed hyper and hypo-autofluorescence. Fluorescein angiography showed combined hyper- and hypo-fluorescence compatible with window defect, staining and blockage. However, no leakage was appreciated in the macula, peripapillary, and peripheral lesions in both eyes. Optical coherence tomography scan showed septate hyporeflective intraretinal spaces in the right eye.

Conclusion and importance

The index report underscore the importance of considering alendronate as an etiologic cause of chorioretinitis, especially in subjects with atypical lesions developing after alendronate therapy. We, therefore, recommend discontinuation of this medication in subjects who develop chorioretinitis after employing this medication.

Multicenter Study on Observation of Acute-phase Responses After Infusion of Zoledronic Acid 5 mg in Chinese Women with Postmenopausal Osteoporosis

OBJECTIVE

It has been reported that acute-phase reactions (APR) after infusion of 5 mg zoledronic acid for the first time is common. This study surveyed the incidence and characteristics of APR in Chinese postmenopausal women receiving 5 mg zoledronic acid intravenously for osteoporosis and to evaluate the efficacy of non-steroidal anti-inflammatory drugs (NSAID) in preventing or alleviating APR following the first 5 mg zoledronic acid infusion.

METHODS

A total of 2601 patients with an average age of 68.14 ± 9.89 years and a mean body mass index of 22.90 ± 3.24 kg/m² from 62 centers in China were treated with 5 mg zoledronic acid intravenously for the first time. The incidence of fever and pain were observed in these patients, and the time of fever or pain onset and duration, and the intensity of fever and grade of pain were also recorded. The dosage, duration, and efficacy of NSAID and safety outcomes were also documented.

RESULTS

At the end of the study, 18 patients are eliminated due to incomplete records of temperature. The incidence of fever was 28.65% (740/2583) within 7 days following zoledronic acid infusion; 98.34% (727/740) occurred at 1.03 ± 0.66 days after infusion and lasted 1.72 ± 0.93 days. A total of 456 (17.53%) patients had newly onset pain (312 of 1187, 26.28%) or experienced pain aggravation (144 of 1414, 10.18%), which mostly occurred within 3 days after zoledronic acid infusion. A total of 1246 (47.6%) patients had received NSAID for a median time of 2.63 ± 2.45 days. Using NSAID for at least 2 days could decrease body temperature by 0.54 ± 0.86°C, increase the percentage of pain-free patients by 6.17%, and reduce the percentage of patients with moderate to severe pain by 8.7%.

CONCLUSIONS

Compared with Western populations, Chinese patients had a higher rate of fever and pain after their first zoledronic acid infusion. These symptoms were often mild to moderate in intensity and transient in duration. NSAID could effectively reduce the incidence and severity of such APR.

Metabolic Effects of Single-Dose Pamidronate Administration in Prostate Cancer Patients with Bone Metastases

Background

Increased osteolysis usually accompanies sclerotic bone metastases from prostate cancer. This provides a rationale for the use of bisphosphonates to treat bone pain and prevent skeletal complications.

Methods

The fasting urinary levels of calcium, hydroxyproline (OHPRO), pyridinolines (PYD), deoxypyridinolines (DPYD), collagen cross-linked N-telopeptide (NTX) and the serum values of calcium, total alkaline phosphatase and relevant bone isoenzyme, bone gla protein (BGP), carboxy-telopeptide of type I collagen (ICTP) and parathyroid hormone (PTH) were determined at baseline and on the 15th, 30th, 60th and 90th days after single-dose (90 mg) pamidronate administration in 35 consecutive prostate cancer patients with bone metastases. These biochemical indices and serum interleukin 6 (IL-6) were also measured after four days in the last consecutive 17 cases.

Results

PYD, DPYD and NTX showed a significant decrease lasting four weeks (p<0.01, <0.01 and <0.001, respectively). OHPRO and ICTP did not change significantly. The NTX decline was greater than that of PYD and DPYD (maximum percent decrease: −71.3, −23.1 and −28.2, respectively). Bone formation markers and serum calcium did not change significantly. Serum PTH showed a rapid initial increase followed by a slow decrease (p<0.001). DPYD and NTX patterns did not correlate with changes in bone pain. As observed in the last 17 cases, the maximum osteolysis inhibition after pamidronate occurred on the fourth day after drug infusion. Serum IL-6 levels showed a short-lived decrease preceded by a transient rise on the fourth day.

Conclusions

Pamidronate is able to induce a decrease in bone resorption without significantly influencing bone formation. The maximum decrease in bone resorption occurs very early. NTX is the most sensitive bone resorption marker in bisphosphonate therapy monitoring. Changes in IL-6 but not bone resorption markers may be useful in the prediction of symptomatic response.

Surgical trauma and low-dose methylprednisolone modulate the severity of the acute-phase response induced by zoledronic acid infusion

The aim of the present study was to investigate risk factors for the development of an acute-phase response (APR) associated with the initial zoledronic acid (ZA) infusion in patients undergoing surgery, and to assess whether its onset may be reduced by post-dose administration of low-dose methylprednisolone (MP) or acetaminophen. A retrospective study of patients with osteoporosis who attended the departments of orthopedics and endocrinology of a single hospital and received 5 mg ZA was conducted; the patients included surgical and non-surgical cases. A total of 450 ZA-naïve patients who were treated with acetaminophen following ZA infusion were stratified based on whether they suffered APR (APR⁺) or not (APR^-). In addition, 155 of the aforementioned acetaminophen-treated patients (acetaminophen group) were compared with another 32 patients from the orthopedic department who were treated with MP immediately following ZA infusion (MP group). Inflammatory marker levels were significantly higher in APR⁺ patients than in APR^- patients, and the odds ratios of experiencing APR following minimally invasive or open surgery were found to be 3.54 (P<0.001) and 5.71 (P<0.001), respectively, compared with non-surgical intervention after multiple adjustments. C-reactive protein levels prior to dosing were positively correlated with body temperature (r=0.023; P<0.001). The severity of APR also exhibited a negative correlation with 23-hydroxyvitamin D3 levels (r=-0.006; P<0.05). Patients treated with MP following surgery and ZA infusion had a significantly lower incidence of APR compared with those treated with acetaminophen (6.3 vs. 62.6%; P<0.05). However, no significant differences were observed in bone mineral density between the MP and acetaminophen groups at 12 months post-surgery. The results of the present study suggest that surgical trauma serves a key role in ZA-associated APR, and low-dose MP may a suitable post-dose treatment to manage the symptoms of APR in patients undergoing surgery.

Drug-Related Adverse Events of Osteoporosis Therapy

Postmenopausal osteoporosis is associated with microarchitectural deterioration and increased risk of fracture. Osteoporosis therapy effectively reduces the risk of vertebral, nonvertebral, and hip fracture and has been associated with increased survival. Currently approved treatments for osteoporosis include bisphosphonates, denosumab, selective estrogen receptor modulators, and teriparatide. This article reviews the adverse events of therapy associated with these medical interventions. Hormone replacement therapy is not included, because it is no longer indicated for the treatment of osteoporosis in all countries. Calcitonin and strontium ranelate are also not included, because their indication for osteoporosis has recently been limited or withdrawn.

Prevention of Vγ9Vδ2 T Cell Activation by a Vγ9Vδ2 TCR Nanobody

Vγ9Vδ2 T cell activation plays an important role in antitumor and antimicrobial immune responses. However, there are conditions in which Vγ9Vδ2 T cell activation can be considered inappropriate for the host. Patients treated with aminobisphosphonates for hypercalcemia or metastatic bone disease often present with a debilitating acute phase response as a result of Vγ9Vδ2 T cell activation. To date, no agents are available that can clinically inhibit Vγ9Vδ2 T cell activation. In this study, we describe the identification of a single domain Ab fragment directed to the TCR of Vγ9Vδ2 T cells with neutralizing properties. This variable domain of an H chain-only Ab (VHH or nanobody) significantly inhibited both phosphoantigen-dependent and -independent activation of Vγ9Vδ2 T cells and, importantly, strongly reduced the production of inflammatory cytokines upon stimulation with aminobisphosphonate-treated cells. Additionally, in silico modeling suggests that the neutralizing VHH binds the same residues on the Vγ9Vδ2 TCR as the Vγ9Vδ2 T cell Ag-presenting transmembrane protein butyrophilin 3A1, providing information on critical residues involved in this interaction. The neutralizing Vγ9Vδ2 TCR VHH identified in this study might provide a novel approach to inhibit the unintentional Vγ9Vδ2 T cell activation as a consequence of aminobisphosphonate administration.

The effect of bisphosphonate treatment on osteoclast precursor cells in postmenopausal osteoporosis: The TRIO study

Bisphosphonates are used to treat bone disease characterised by increased bone resorption by inhibiting the activity of mature osteoclasts, resulting in decreased bone turnover. Bisphosphonates may also reduce the population of osteoclast precursor cells. Our aims were to investigate the effect of bisphosphonates on i) osteoclast precursor cells and ii) circulating cytokine and cytokine receptor in postmenopausal women with osteoporosis compared with healthy premenopausal women. Participants were 62 postmenopausal women (mean age 66) from a 48-week parallel group trial of bisphosphonates. They received ibandronate 150mg/month (n=22), alendronate 70mg/week (n=19) or risedronate 35mg/week (n=21). Fasting blood was collected at baseline, weeks 1 and 48. At baseline, blood was also collected from 25 healthy premenopausal women (mean age 37) to constitute a control group. Peripheral blood mononuclear cells were extracted and stained for CD14, M-CSFR, CD11b and TNFRII receptors. Flow cytometry was used to identify cells expressing CD14⁺ and M-CSFR⁺ or CD11b⁺ or TNFRII⁺. RANKL and OPG were measured to evaluate potential mediation of the bisphosphonate effect. After 48weeks of treatment, there was a decrease in the percentage of cells expressing M-CSFR and CD11b receptors by 53% and 49% respectively (p<0.01). Cells expressing M-CSFR and CD11b were decreased with ibandronate and risedronate after 48weeks to the lower part of the premenopausal reference interval. These effects were not significantly different between each of the treatment groups. There was no significant effect on RANKL and OPG throughout the study period. Bisphosphonates inhibit bone resorption in the short-term by direct action on mature osteoclasts. There is also a later effect mediated in part by a reduction in the population of circulating osteoclast precursors.

Carpal Tunnel Syndrome Associated with Oral Bisphosphonates. A Population-Based Cohort Study

BACKGROUND

Bisphosphonates are widely used to prevent osteoporotic fractures. Some severe musculoskeletal reactions have been described with this medication; among them, some cases of carpal tunnel syndrome. Thus, the aim of this study was to explore whether bisphosphonates may be associated with this syndrome.

METHODS

A cohort study was conducted to compare exposed to unexposed women; the exposed group was that composed of women having received at least one prescription of an oral bisphosphonate. For the purpose, we used information from The Health Improvement Network (THIN) database. The outcome of interest was defined as those women diagnosed with carpal tunnel syndrome. A survival analysis was performed; the Cox proportional hazard model was used to calculate hazard ratios and 95% confidence intervals, and to adjust for identified confounding variables.

RESULTS

Out of a sample of 59,475 women older than 51 years, 19,825 were treated with bisphosphonates during the period studied. No differences in age distribution or mean follow-up time were observed between the two groups in comparison. Overall, there were 572 women diagnosed with carpal tunnel syndrome, 242 (1.2%) in the group exposed to bisphosphonates, and 330 (0.8%) in the unexposed. An adjusted hazard ratio of developing carpal tunnel syndrome of 1.38 (95%CI, 1.15-1.64) was found for women exposed to bisphosphonates; no significant changes in the hazard ratios were found when considering different levels of bisphosphonate exposure.

CONCLUSIONS

An increased risk of carpal tunnel syndrome is associated with the use of bisphosphonates in postmenopausal women.

Effects of Artemisia Princeps Supplementation on Bone Metabolism in Ovariectomized Rats

The aim of this study was to investigate the effects of Artemisia princeps (AP) extract on bone metabolism and its potential role in the prevention of osteoporosis in ovariectomized rats. Twenty-six female Sprague-Dawley rats were divided into five groups and treated as follows: sham-operated control group (SHAM); ovariectomized control group (OVX), ovariectomized group treated by gavage with 10 mg/kg/day alendronate (ALEN); ovariectomized group treated by gavage with 100 mg/kg/day Artemisia princeps (AP100); ovariectomized group treated by gavage with 300 mg/kg/day Artemisia princeps (AP300). Treatment of ovariectomized rats with AP extracts for 15 weeks prevented the reduction in bone thickness and trabecular bone mineral density caused by urinary Ca and Cr excretion, and also prevented the increase in bone turnover by maintaining the serum Ca/P ratio. As a result, the microarchitecture of the trabecular bone and cortical bone after ovariectomy was markedly improved by administration of AP extracts. In conclusion, AP prevented bone loss and osteoclast activity associated with high bone turnover in ovariectomized rats by controlling the serum Ca/P ratio and through anti-inflammatory and anti-oxidant properties. Our data implicate AP as a promising therapeutic option for the improvement of postmenopausal osteoporosis.

The Effects of Re-challenge in Patients with a History of Acute Anterior Uveitis Following Intravenous Zoledronate

To determine the incidence of adverse ocular side effects following re-challenge in patients who previously developed ocular symptoms following intravenous zoledronate. Secondary data analysis of a large, prospective, randomized, double-blind, placebo-controlled clinical trial was performed. Participants consisted of postmenopausal females with osteopenia randomized to placebo (N = 1000) or zoledronate 5 mg (N = 1001) intravenous infusion. Recruitment occurred over a 2-year period, with the first infusion being administered at recruitment, and subsequent infusions every 18 months. Eight participants developed acute anterior uveitis (AAU) (diagnosed by an ophthalmologist) following the first infusion of zoledronate. Following appropriate ophthalmic treatment, no patients had visual loss or other ocular sequelae. One further participant reported "sore red eyes" but did not attend for ophthalmology review. Six participants declined further infusions. The remaining three participants were administered two further zoledronate infusions, 18 months apart, and none developed any ocular symptoms following each infusion. As a precaution, two of these participants were examined by an ophthalmologist 3 days after their second infusion and neither had ocular symptoms or signs of AAU and no subsequent ocular side effects. AAU following zoledronate infusion is likely to be part of the acute phase response. If treated promptly under the care of an ophthalmologist, the visual prognosis is excellent. The results of this study suggest that the development of AAU should not be a contraindication to further infusion. However, in such cases, patients should be warned of the symptoms of AAU (ocular pain, redness, photophobia or blurred vision) and should be promptly referred to an ophthalmologist if symptoms develop.

Inflammatory eye reactions with bisphosphonates and other osteoporosis medications: what are the risks?

Inflammatory eye reactions (IERs) are rare but have been associated with medications to treat osteoporosis. The aim of this review is to summarize the current literature on the association between IERs and specific medications to treat osteoporosis (bisphosphonates, selective estrogen receptor modulators, strontium, denosumab and teriparatide). We cover the known epidemiology, potential pathogenic mechanisms and a resume of unanswered questions. Briefly, this review highlights that none of the existing randomized clinical trials were powered to identify these rare adverse events, and the majority of the information available is from spontaneous case reports and case series reporting associations between bisphosphonates and IERs. No case reports describe IERs after other anti-osteoporosis medications. Importantly, some case reports describe recurrence of the IER after affected patients were rechallenged with the same or another bisphosphonate, and that no reported cases resolved without discontinuation of the bisphosphonate. However, three large population-based cohort studies have shown conflicting results between osteoporosis treatments and IERs, but overall these studies suggest that IERs may actually be part of underlying inflammatory disease processes that also cause osteoporosis, rather than due to the medications used to treat osteoporosis themselves. There are no clear pathogenic mechanisms for how bisphosphonates could potentially cause IERs. However, the drug is secreted into the tears by the lacrimal gland and could cause irritation to the mucous membranes with subsequent release of inflammatory mediators, similar to the systemic response typically seen after infusion of bisphosphonates. However, in summary it is still not known whether there is a true causal association between bisphosphonates or other anti-osteoporosis medications and IERs, or whether it is confounding by indication and is actually due to underlying inflammatory diseases that cause both osteoporosis and IERs.

Incidence of ocular side effects with intravenous zoledronate: secondary analysis of a randomized controlled trial

SUMMARY

This prospective study showed that the incidence of acute anterior uveitis, confirmed by ophthalmic examination, in patients receiving intravenous zoledronate infusions as part of a randomized controlled trial for fracture prevention is 1.1%.

INTRODUCTION

We prospectively investigated the incidence of ocular side effects after a single intravenous zoledronate infusion.

METHODS

In a secondary analysis of a double-blind, placebo-controlled trial in which early post-menopausal women (N=1054) with normal bone density or osteopenia were randomized to infusion of zoledronate 5 mg (N=703) or placebo (N=351), we analyzed significant adverse ocular events occurring within 3 months.

RESULTS

Fourteen participants reported ocular symptoms after the infusion. All were examined by an ophthalmologist and eight were diagnosed with acute anterior uveitis (AAU) and one with sectoral episcleritis. The incidence of AAU and episcleritis was 1.1% (95% CI 0.5-2.1) and 0.1% (95% CI 0.0-0.7), respectively, in the zoledronate group and 0% for both conditions in the placebo group (95% CI 0.0-0.8). The mean time from infusion to symptom onset for AAU was 3 days (range 2-4). Three cases were bilateral. AAU was mild-moderate in seven participants and severe in one. All affected eyes were treated with topical cyclopentolate 1% (to break, or minimize, posterior synechiae), and intensive, potent, topical corticosteroids with a tapering regime based on treatment response. The mean duration of topical corticosteroid was 26±10 days (range 17-44). The mean, best corrected visual acuity was 20/20 (range 20/20-20/40) at presentation, which remained unchanged after AAU resolution. None of the participants lost vision, and no long-term sequelae were reported at last follow-up (range 3-13 months post-infusion).

CONCLUSIONS

Prescribers should inform patients about the possibility of ocular side effects with zoledronate infusions and refer promptly to an ophthalmologist if symptoms develop.

Drug-induced uveitis

INTRODUCTION

Drug-induced uveitis is a well described but often overlooked and/or misdiagnosed adverse reaction to medication. There are an increasing number of medications that have been related to the onset of intraocular inflammation. Identification of these inciting agents may decisively help the diagnostic algorithm involving new cases of uveitis.

AREAS COVERED

This review intends to be an updated comprehensive, practical guide for practitioners regarding the main drugs that have been associated with uveitis. A classification proposed by Naranjo et al. in 1981 for establishing potential causality is applied examining possible mechanisms of action. A guide for clinicians about the rationale of these observations when dealing with patients with uveitis is provided.

EXPERT OPINION

Several agents with different routes of administration (systemic, topical and/or intraocular) may cause intraocular inflammation. The mechanism behind ocular inflammation is frequently unknown. Clinicians should be aware of the potential drug effect to optimize diagnosis and management of such patients.

Risk of atrial fibrillation with use of oral and intravenous bisphosphonates

Clinical studies suggest an association between bisphosphonate use and new-onset atrial fibrillation (AF). Intravenous bisphosphonates more potently increase the release of inflammatory cytokines than do oral bisphosphonates; thus, the risk of developing AF may be greater with intravenous preparations. We have evaluated incidence of new-onset AF with use of oral and intravenous bisphosphonates through a systematic review and meta-analysis of the literature. We searched PubMed, CINAHL, Cochrane Central Register of Controlled Trials, Scopus, and EMBASE databases for observational studies and randomized controlled trials (RCTs) published from 1966 to April 2013 that reported the number of patients developing AF with use of oral or intravenous bisphosphonates. The random-effects Mantel-Haenszel test was used to evaluate the relative risk of AF with use of oral and intravenous bisphosphonates. Nine studies (5 RCTs and 4 observational studies) were included in the final analysis. Pooled data from RCTs and observational studies (n = 135,347) showed a statistically significantly increased risk of new-onset AF with both intravenous (relative risk 1.40, 95% confidence interval 1.32 to 1.49) and oral (relative risk 1.22, 95% confidence interval 1.14 to 1.31) bisphosphonates. The z statistic, which assesses the difference between the 2 risk ratios, indicated higher risk of AF with intravenous bisphosphonates versus oral bisphosphonates (p = 0.03). In conclusion, pooled data from RCTs and observational studies suggest that risk of AF is increased by use of oral or intravenous bisphosphonates but further suggest that risk is relatively greater with intravenous preparations.

Bisphosphonates for osteoporosis in people with cystic fibrosis

BACKGROUND

Osteoporosis is a bone mineralisation disorder occurring in about one third of adults with cystic fibrosis. Bisphosphonates can increase bone mineral density and decrease the risk of new fractures in post-menopausal women and people receiving long-term oral corticosteroids.

OBJECTIVES

To assess the effects of bisphosphonates on the frequency of fractures, bone mineral density, quality of life, adverse events, trial withdrawals, and survival in people with cystic fibrosis.

SEARCH METHODS

We searched the Cystic Fibrosis and Genetic Disorders Group Trials Register of references (identified from electronic database searches and handsearches of journals and abstract books) on 13 January 2014.Additional searches of PubMed were performed on 13 January 2014.

SELECTION CRITERIA

Randomised controlled trials of at least six months duration studying bisphosphonates in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials and extracted data. Trial investigators were contacted to obtain missing data.

MAIN RESULTS

Nine trials were identified and seven (with a total of 237 adult participants) were included.Data were combined (when available) from six included studies in participants without a lung transplant. Data showed that there was no significant reduction in fractures between treatment and control groups at 12 months, odds ratio 0.72 (95% confidence interval 0.13 to 3.80). No fractures were reported in studies with follow-up at 24 months. However, in patients taking bisphosphonates after six months the percentage change in bone mineral density increased at the lumbar spine, mean difference 4.61 (95% confidence interval 3.90 to 5.32) and at the hip or femur, mean difference 3.35 (95% confidence interval 1.63 to 5.07); but did not significantly change at the distal forearm, mean difference -0.49 (95% confidence interval -2.42 to 1.45). In patients taking bisphosphonates, at 12 months the percentage change in bone mineral density increased at the lumbar spine, mean difference 6.10 (95% confidence interval 5.10 to 7.10) and at the hip or femur, mean difference 4.35 (95% confidence interval 2.99 to 5.70). At 24 months, in patients treated with bisphosphonates the percentage change in bone mineral density also increased at the lumbar spine, mean difference 5.49 (95% confidence interval 4.38 to 6.60) and at the hip or femur, mean difference 6.05 (95% confidence interval 3.74 to 8.36). There was clinical heterogeneity between studies and not all studies reported all outcomes. Bone pain was the most common adverse event with intravenous agents. Flu-like symptoms were also increased in those taking bisphosphonates.In participants with a lung transplant (one study), intravenous pamidronate did not change the number of new fractures. At axial sites, bone mineral density increased with treatment compared to controls: percentage change in bone mineral density at lumbar spine, mean difference 6.20 (95% confidence interval 4.28 to 8.12); and femur mean difference 7.90 (95% confidence interval 5.78 to 10.02).

AUTHORS' CONCLUSIONS

Oral and intravenous bisphosphonates increase bone mineral density in people with cystic fibrosis. Severe bone pain and flu-like symptoms may occur with intravenous agents. Additional trials are needed to determine if bone pain is more common or severe (or both) with the more potent zoledronate and if corticosteroids ameliorate or prevent these adverse events. Additional trials are also required to further assess gastrointestinal adverse effects associated with oral bisphosphonates. Trials in larger populations are needed to determine effects on fracture rate and survival.

Adjuvant bisphosphonates in breast cancer: has the time come?

SUMMARY Bone metabolism is highly affected by changes in ovarian function, which is a common consequence of the treatment of breast cancer patients. Osteopenia and osteoporosis increase the risk of fractures, which are associated with profound loss in quality of life. Bisphosphonates are used with the objective of preventing bone loss in patients with osteoporosis, but data suggest that agents such as zoledronic acid might play a role in the prevention of metastatic disease and therefore have been evaluated in numerous randomized trials in the adjuvant setting. This review article will discuss and analyze the available data regarding the use of bisphosphonates in the adjuvant setting for breast cancer patients. It will focus on the use of bisphosphonates as anticancer agents, but will also discuss the use of these agents for the prevention of bone loss.

The role of cytokines and adipocytokines in zoledronate-induced acute phase reaction in postmenopausal women with low bone mass

OBJECTIVE

Patients treated with intravenous zoledronate frequently experience an acute phase reaction (APR) characterized by flu-like symptoms and increased levels of inflammatory cytokines. We aimed to define the role of various cytokines/adipocytokines in zoledronate-induced APR and develop a prognostic model for its prediction.

PATIENTS AND MEASUREMENTS

Fifty-one postmenopausal women with low bone mass were subjected to zoledronate intravenous infusion. Patients were divided into those who experienced APR (APR+) and those who did not (APR-). APR was clinically defined by body temperature and the visual analogue pain scale for musculoskeletal symptoms. White blood cell count, leucocytic subpopulations, C-reactive protein, interleukin-6, tumour necrosis factor-alpha, visfatin, resistin and leptin were measured before and 48 h following the infusion. The quantitative insulin sensitivity check index (QUICKI) and homoeostasis model of assessment - insulin resistance (HOMA-IR) were calculated to assess insulin sensitivity and resistance, respectively.

RESULTS

(APR+) patients were younger and had lower baseline visfatin and higher baseline lymphocytes and phosphate compared with APR- patients. QUICKI decreased and HOMA-IR increased in APR+ patients while remained unchanged in APR- patients. In binary logistic regression analysis, a model containing previous bisphosphonate treatment, age, body mass index, lymphocytes and visfatin, which predicted zoledronate-induced APR with 82·1% sensitivity and 73·9% specificity, was selected. In this model, lymphocytes (P = 0·010) and visfatin (P = 0·029) at baseline could independently predict APR.

CONCLUSIONS

Zoledronate-induced APR is associated with serum increases of pro-inflammatory cytokines and an increase of insulin resistance. Patients with higher lymphocytes and lower visfatin levels at baseline are at higher risk for APR.

Long-term effects of amino-bisphosphonates on circulating γδ T cells

The aim of this study was to explore whether desensitization to the occurrence of the acute-phase response (APR) in patients previously treated with amino-bisphosphonates (N-BPs) is due to a long-lasting reduction in the number of circulating γδ T cells. Circulating lymphocyte subpopulation counts were obtained from 63 patients with postmenopausal or senile osteoporosis at baseline and after 2 days and 12 months of the first intravenous (IV) 5 mg zoledronic acid (ZOL) infusion. At baseline both the proportion and absolute number of circulating γδ T cells were significantly higher in patients who had never used N-BPs vs. previous users, either oral or IV. A typical APR was observed in none of the patients given IV ZOL a year earlier, in 6 (22 %) of the patients previously treated with oral N-BPs, and in 13 (57 %) of the patients naive to any N-BP treatment. In patients naive to N-BPs, a significant reduction in both total lymphocytes and their subsets was observed 2 days after ZOL infusion; all these changes returned to baseline values 1 year later with the exception of γδ T cells, which remained significantly lower in terms of both proportion and absolute number. These results indicate for the first time that both IV and oral N-BP treatments are associated with a long-lasting decrease in circulating γδ T cells, and this may explain the lower incidence of APR in patients previously exposed to N-BPs. Other clinical implications of this sustained effect of N-BPs on immune-regulatory cells might be important.

Analgesic effects of the non-nitrogen-containing bisphosphonates etidronate and clodronate, independent of anti-resorptive effects on bone

Nitrogen-containing bisphosphonates (NBPs) have greater anti-bone-resorptive effects than non-nitrogen-containing bisphosphonates (non-NBPs). Hence, NBPs are the current first-choice drug for osteoporosis. However, NBPs carry a risk of osteonecrosis of jaws. Some animal and human studies suggest that non-NBPs may have anti-bone-resorptive effect-independent analgesic effects, but there has been no detailed comparison between NBPs and non-NBPs. Here, we compared the analgesic effects of several non-NBPs and NBPs, using (a) writhing responses induced in mice by intraperitoneal injection of 1% acetic acid, (b) acetic acid-induced neuronal expression of c-Fos, (c) acetic acid-induced elevation of blood corticosterone, and (d) hindpaw-licking/biting responses induced by intraplantar injection of capsaicin. Among the NBPs and non-NBPs tested, only etidronate and clodronate displayed clear analgesic effects, with various routes of administration (including the oral one) being effective. However, they were ineffective when intraperitoneally injected simultaneously with acetic acid. Intracerebroventricular administration of etidronate or clodronate, but not of minodronate (an NBP), was also effective. The effective doses of etidronate and clodronate were much lower in writhing-high-responder strains of mice. Etidronate and clodronate reduced acetic acid-induced c-Fos expression in the brain and spinal cord, and also the acetic acid-induced corticosterone increase in the blood. Etidronate and clodronate each displayed an analgesic effect in the capsaicin test. Etidronate and clodronate displayed their analgesic effects at doses lower than those inducing anti-bone-resorptive effects. These results suggest that etidronate and clodronate exert potent, anti-bone-resorptive effect-independent analgesic effects, possibly via an interaction with neurons, and that they warrant reappraisal as safe drugs for osteoporosis.

Bisphosphonates for osteoporosis in people with cystic fibrosis

BACKGROUND

Osteoporosis is a bone mineralisation disorder occurring in about one third of adults with cystic fibrosis. Bisphosphonates can increase bone mineral density and decrease the risk of new fractures in post-menopausal women and people receiving long-term oral corticosteroids.

OBJECTIVES

To assess the effects of bisphosphonates on the frequency of fractures, bone mineral density, quality of life, adverse events, trial withdrawals, and survival in people with cystic fibrosis.

SEARCH METHODS

We searched the Cystic Fibrosis and Genetic Disorders Group Trials Register of references (identified from electronic database searches and handsearches of journals and abstract books) on 15 February 2012.Additional searches of PubMed were performed on 14 May 2011.

SELECTION CRITERIA

Randomised controlled trials of at least six months duration studying bisphosphonates in people with cystic fibrosis.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials and extracted data. Trial investigators were contacted to obtain missing data.

MAIN RESULTS

Nine trials were identified and seven (with a total of 237 adult participants) were included.Data were combined (when available) from six included studies in participants without a lung transplant. Data showed that there was no significant reduction in fractures between treatment and control groups at 12 months, odds ratio 0.72 (95% confidence interval 0.13 to 3.80). No fractures were reported in studies with follow-up at 24 months. However, in patients taking bisphosphonates after six months the percentage change in bone mineral density increased at the lumbar spine, mean difference 4.61 (95% confidence interval 3.90 to 5.32) and at the hip or femur, mean difference 3.35 (95% confidence interval 1.63 to 5.07); but did not significantly change at the distal forearm, mean difference -0.49 (95% confidence interval -2.42 to 1.45). In patients taking bisphosphonates, at 12 months the percentage change in bone mineral density increased at the lumbar spine, mean difference 6.10 (95% confidence interval 5.10 to 7.10) and at the hip or femur, mean difference 4.35 (95% confidence interval 2.99 to 5.70). At 24 months, in patients treated with bisphosphonates the percentage change in bone mineral density also increased at the lumbar spine, mean difference 5.49 (95% confidence interval 4.38 to 6.60) and at the hip or femur, mean difference 6.05 (95% confidence interval 3.74 to 8.36). There was clinical heterogeneity between studies and not all studies reported all outcomes. Bone pain was the most common adverse event with intravenous agents. Flu-like symptoms were also increased in those taking bisphosphonates.In participants with a lung transplant (one study), intravenous pamidronate did not change the number of new fractures. At axial sites, bone mineral density increased with treatment compared to controls: percentage change in bone mineral density at lumbar spine, mean difference 6.20 (95% confidence interval 4.28 to 8.12); and femur mean difference 7.90 (95% confidence interval 5.78 to 10.02).

AUTHORS' CONCLUSIONS

Oral and intravenous bisphosphonates increase bone mineral density in people with cystic fibrosis. Severe bone pain and flu-like symptoms may occur with intravenous agents. Additional trials are needed to determine if bone pain is more common or severe (or both) with the more potent zoledronate and if corticosteroids ameliorate or prevent these adverse events. Additional trials are also required to further assess gastrointestinal adverse effects associated with oral bisphosphonates. Trials in larger populations are needed to determine effects on fracture rate and survival.

Extraskeletal benefits and risks of calcium, vitamin D and anti-osteoporosis medications

Drugs used for the prevention and the treatment of osteoporosis exert various favourable and unfavourable extra-skeletal effects whose importance is increasingly recognized notably for treatment selection.

INTRODUCTION

The therapeutic armamentarium for the prevention and the treatment of osteoporosis is increasingly large, and possible extra-skeletal effects of available drugs could influence the choice of a particular compound.

METHODS

The present document is the result of a national consensus, based on a systematic and critical review of the literature.

RESULTS

Observational research has suggested an inverse relationship between calcium intake and cardiovascular diseases, notably through an effect on blood pressure, but recent data suggest a possible deleterious effect of calcium supplements on cardiovascular risk. Many diverse studies have implicated vitamin D in the pathogenesis of clinically important non-skeletal functions or diseases, especially muscle function, cardiovascular disease, autoimmune diseases and common cancers. The possible effects of oral or intravenous bisphosphonates are well-known. They have been associated with an increased risk of oesophageal cancer or atrial fibrillation, but large-scale studies have not found any association with bisphosphonate use. Selective oestrogen receptor modulators have demonstrated favourable or unfavourable extra-skeletal effects that vary between compounds. Strontium ranelate has a limited number of non-skeletal effects. A reported increase in the risk of venous thromboembolism is not found in observational studies, and very rare cases of cutaneous hypersensitivity reactions have been reported. Denosumab has been introduced recently, and its extra-skeletal effects still have to be assessed.

CONCLUSION

Several non-skeletal effects of bone drugs are well demonstrated and influence treatment choices.

Use of bisphosphonate and risk of atrial fibrillation in older women with osteoporosis

Concerns have been raised among clinicians and patients whether or not bisphosphonates increase the risk of atrial fibrillation. In this large cohort study, increased risk of atrial fibrillation was not found to be associated with bisphosphonate. In fact, bisphosphonate even showed a protective effect against cardiac arrhythmia compared to other osteoporosis medications.

INTRODUCTION

Increased risk of atrial fibrillation among bisphosphonate users has been reported; however, the results from these studies are controversial. The purpose of this study was to evaluate the risk of atrial fibrillation associated with bisphosphonate use in older women.

METHODS

We used the Korean Health Insurance Review and Assessment Service claims database from May 1, 2005 to June 30, 2006. Retrospective cohort analysis was conducted on women 65 years or older with newly diagnosed cases of osteoporosis (ICD 10 code: M80, M81) who had not previously taken any medications for osteoporosis. Bisphosphonate-exposed and non-exposed patients were followed until they were either diagnosed with atrial fibrillation (ICD 10 code: I48) or until the end of the study. The Cox proportional hazards model was used to calculate hazard ratios and the 95% confidence intervals.

RESULTS

Atrial fibrillation was reported in 626 of the 120,319 patients (0.52%) treated with bisphosphonates and 66 of 9,863 patients (0.67%) treated with other osteoporosis medications. Overall hazard ratio for developing atrial fibrillation in the bisphosphonate-treated group was 0.52 (95% CIs, 0.29-0.91). In patients with a medication possession ratio greater than 0.7, the hazard ratio was lower (HR 0.41, 95% CIs 0.23-0.75). In the subgroup analysis, alendronate showed a statistically significant protective effect against the risk of atrial fibrillation with a hazard ratio of 0.75 (95% CI, 0.58-0.97).

CONCLUSION

Among older Korean women with osteoporosis, bisphosphonate was found to have a protective effect against atrial fibrillation.

Circulating γδ T cells and the risk of acute-phase response after zoledronic acid administration

The use of intravenous nitrogen-containing bisphosphonates (N-BPs) is associated with the appearance of an acute phase response (APR) in a proportion of the patients for reasons that are poorly understood. The APR was attributed to the indirect activation of γδ T cells with the release of interferon-γ and tumor necrosis factor (TNF). Forty patients with postmenopausal or senile osteoporosis (age range = 53-91 years) never previously treated with intravenous (i.v.) bisphosphonate, received a single 5-mg zoledronic acid (ZOL) iv infusion over 15 minutes. White blood cells were counted and analyzed with an automated hematology analyzer (ADVIA 2120i Siemens, New York, USA) and by flow cytometer (BD FACSCanto, Becton Dickinson). The occurrence of APR was defined by the occurrence of fever (>37 °C) during the next 2 days. Forty-two percent of patients (17 of 40) receiving the infusion of ZOL experienced an APR. Compared with the others they were younger (69 ± 7 years versus 74 ± 8 years; p = 0.06), and both the proportion and absolute number of γδ T cells were significant higher (p = 0.02 and p = 0.013, respectively). Nonsignificant differences were found between the two groups for white blood cells and for the other circulating lymphocyte subpopulations. Age was inversely correlated with circulating γδ T cells (p = 0.003) but the difference between the two groups in circulating γδ T cells persisted for age-adjusted values and vice versa. In conclusion, the results of this study indicate that the number of circulating γδ T cells, together with age, are important determinant of the occurrence of APR after intravenous infusion of ZOL and possibly of any other N-BPs.

A rare case of zolendronate infusion complication leading to glaucoma filtration surgery

Zolendronic acid is a nitrogenous biphosphonate commonly used as an intravenous infusion for the management of Paget's disease, osteoporosis, and hypercalcemia of malignancy. We report a rare and challenging complication of zolendronate infusion: unilateral acute anterior uveitis followed by persistently raised intraocular pressure despite being on four different classes of antiglaucoma medication. The challenge was that the patient required topical steroid to treat her uveitis in the background of known glaucoma with corresponding steroid response. She eventually underwent a left phacotrabeculectomy augmented with 5-fluorouracil. Four weeks postoperatively she developed an encapsulated bleb and underwent needling with 5-fluorouracil. This case highlights the importance of having a high index of suspicion for anterior uveitis in patients with a red and painful eye after initiating biphosphonate therapy. Caution should also be exercised when prescribing biphosponates to glaucoma patients.

Bisphosphonate treatment of benign multifocal and unifocal osteolytic tumours of bone

Growth of benign tumours and tumour-like lesions of bone results in osteolysis which may cause pathological fracture. Bisphosphonates are anti-osteolytic agents which have proved effective in the treatment of number of osteolytic conditions. In this study we report the results of treatment with the aminobisphosphonate, pamidronate, of three benign osteolytic tumours of bone, two cases of fibrous dysplasia and one of Langerhans cell histiocytosis. In all three cases there was clinical and radiological improvement following treatment. Radiologically, bone lesions did not exhibit progressive enlargement. Two cases of fibrous dysplasia also showed features suggestive of increased bone formation. These findings indicate that bisphosphonates are likely to be useful in controlling the osteolysis of benign tumours/tumour-like lesions of bone, particularly in those cases where surgical intervention is not possible or multifocal lesions are present.

Fluvastatin does not prevent the acute-phase response to intravenous zoledronic acid in post-menopausal women

The acute-phase response (APR) to aminobisphosphonates is triggered by activation of γδ T cells, resulting in pro-inflammatory cytokine release. Statins prevent aminobisphosphonate-induced γδ T cell activation in vitro, raising the possibility that statins might prevent the APR in vivo. The objective of this study was to determine whether fluvastatin prevents the APR to zoledronic acid in post-menopausal women. A double-blind, randomised, placebo-controlled study was conducted in 60 healthy, post-menopausal, female volunteers (mean age 60.6 ± 4.0). Volunteers received 5 mg zoledronic acid by intravenous infusion, and either three times 40 mg fluvastatin (0 hr, 24 hr and 48 hr), 40 mg fluvastatin (0 hr) plus placebo (24 hr and 48 hr), or placebo (0 hr, 24 hr and 48 hr), orally. Post-infusion symptoms were assessed by questionnaire. Changes in γδ T cell levels, pro-inflammatory cytokines (TNFα, IFNγ, IL-6) and C-reactive protein (CRP) were measured in peripheral blood at various time-points post-infusion. Zoledronic acid administration triggered increased serum levels of TNFα, IFNγ, IL-6 and CRP in ≥70% of study volunteers, whilst characteristic APR symptoms were observed in >50% of participants. Zoledronic acid also induced a transient fall in circulating Vγ9Vδ2 T cell levels at 48 hr, consistent with Vγ9Vδ2 T cell activation. Concurrent fluvastatin administration did not prevent zoledronic acid-induced cytokine release, alter circulating Vγ9Vδ2 T cell levels, nor diminish the frequency or severity of APR symptoms. In conclusion, intravenous zoledronic acid induced pro-inflammatory cytokine release and APR symptoms in the majority of study participants, which was not prevented by co-administration of fluvastatin.