Uveitis associated with pamidronate

Ocular Side Effects of Bisphosphonates: A Review of Literature

In rare cases, bisphosphonates are well established to cause ocular inflammation, presenting as uveitis, episcleritis, scleritis, orbital inflammation, and/or conjunctivitis. Some reports of bisphosphonate-associated neuro-ophthalmic complications also exist. We identified 101 reports in the literature relating to bisphosphonate-associated ocular complications. In a great majority of cases, symptoms resolve after discontinuation of the drug and anti-inflammatory treatment. Many cases recur if rechallenged with the same bisphosphonate. First-generation nonamino bisphosphonates, including clodronate and etidronate, are not associated with ocular inflammation. Only 2nd- and 3rd-generation amino bisphosphonates, including pamidronate, alendronate, risedronate, ibandronate, and zoledronate are associated with these complications. The mechanism of bisphosphonate-induced ocular inflammation may be related to activation of γ/δ T cells or M1 macrophages. Intravenous forms, such as pamidronate and zoledronate, tend to have higher rates and faster onset of ocular inflammation, generally presenting within days of infusion. In oral bisphosphonates, such as alendronate and risedronate, these complications present with more sporadic timing. Rates of complications are also higher when bisphosphonates are used for malignancy, as doses tend to be higher compared with doses for osteoporosis.

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.

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.

Oral Bisphosphonates and Risk of Wet Age-Related Macular Degeneration

PURPOSE

To examine the risk of age-related macular degeneration (AMD) with oral bisphosphonates.

DESIGN

Three study designs were used: (1) disproportionality analysis; (2) case-control study; (3) self-controlled case series (SCCS).

METHODS

setting: (1) Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) Database; (2) 2 patient cohorts from British Columbia, Canada.

STUDY POPULATION

(1) All reports of AMD to the FDA with oral bisphosphoantes; (2) patients with wet AMD in British Columbia (2009-2013) and 1 million controls (2000-2007).

INTERVENTION

Oral bisphosphonates.

MAIN OUTCOME MEASURES

(1) Reports of AMD to the FDA; (2) first diagnosis of wet AMD verified by a retina specialist in British Columbia.

RESULTS

In the disproportionality analysis there were 133 cases of AMD reported with alendronate, 20 with ibandronate, and 14 with risedronate. The reported odds ratios (RORs) for alendronate, ibandronate, and risedronate were 3.82 (95% CI: 2.94-4.96), 2.40 (95% CI: 1.49-3.86), and 2.87 (95% CI: 1.58-5.19), respectively. In the case-control analysis there were 6367 cases and 6370 corresponding controls. The adjusted OR for wet AMD among regular users of bisphosphonates in the 1, 2, and 3 years prior to the index date were 1.24 (1.12-1.38), 1.38 (1.22-1.56), and 1.59 (1.38-1.82), respectively. In the SCCS analysis there were 198 cases of wet AMD on continuous bisphosphonate therapy. The rate ratio for wet AMD for continuous bisphosphonate use was 1.99 (95% CI: 1.41-2.79). We did not have information on intravenous bisphosphonates.

CONCLUSIONS

Continuous users of oral bisphosphonates are at a higher risk of developing wet AMD. Given the observational nature of this study and limitation of the data, future studies are needed to confirm these findings.

Pro-inflammatory and anti-angiogenic effects of bisphosphonates on human cultured retinal pigment epithelial cells

AIM

Bisphosphonates have been shown to induce ocular inflammatory diseases such as uveitis and scleritis, while being protective against angiogenic diseases like neovascular age-related macular degeneration (AMD). Therefore, we studied the effects of bisphosphonates on primary culture of human fetal retinal pigment epithelium (hRPE), a cell type known to secrete both inflammatory and angiogenic factors. Alendronate and etidronate were selected for this experiment as they are members of the two structurally different classes of bisphosphonates.

METHODS

Primary cultures of hRPE were serum-starved for 24 h and then treated for 24 h with alendronate (0.0001, 0.1, 100 µM) or etidronate (0.01, 1 µM). Cell viability was measured using the MTT assay. Investigation of secreted cytokines induced by bisphosphonates was performed using a human cytokine 29-Plex Panel (Bio-Plex) array and the results were analysed with an analysis of variance (ANOVA).

RESULTS

Etidronate, at the lower concentration, significantly increased the expression of interleukin (IL)-6 (p=0.03) and IL-8 (p=0.04). At the higher concentration, etidronate significantly decreased the expression of granulocyte macrophage colony-stimulating factor (p=0.02) and basic fibroblast growth factor (bFGF) (p=0.02). Alendronate, at the highest concentration, significantly increased the expression of IL-8 (p=0.02) and decreased the expression of eotaxin (p=0.02). Alendronate also significantly decreased the expression of bFGF at all concentrations (p<0.05) and demonstrated a trend towards decreasing vascular endothelial growth factor expression at low concentration.

CONCLUSIONS

Alendronate and etidronate display dose dependent effects in hRPE cells. Alendronate and etidronate administration resulted in concentration dependent elevations in inflammatory cytokines. Furthermore, alendronate and etidronate administration resulted in reduced expression of a number of angiogenic factors. These findings may explain the increased incidence of ocular inflammation as well as the therapeutic effect on neovascular AMD which have been described with bisphosphonates.

Drug-induced uveitis

A number of medications have been associated with uveitis. This review highlights both well-established and recently reported systemic, topical, intraocular, and vaccine-associated causes of drug-induced uveitis, and assigns a quantitative score to each medication based upon criteria originally described by Naranjo and associates.

Inflammatory eye reactions in patients treated with bisphosphonates and other osteoporosis medications: cohort analysis using a national prescription database

Ocular inflammatory reactions have been described in patients on bisphosphonate treatment. We estimated the incidence rate of ocular inflammation at 3 and 12 months in patients treated for osteoporosis using a register-based cohort linked to prescription data (hospitals and private practice) and hospital data. From January 1, 1997 to December 31, 2007, a total of 88,202 patients beginning osteoporosis therapy were identified. Of those patients, 82,404 (93%) began oral bisphosphonates and 5798 (7%) nonbisphosphonates. Within the first year of treatment, 4769 (5.4%) of patients on osteoporosis therapy filled one or more prescriptions for topical eye steroids (TES). TES treatment rates (per 1000 patient-years) in the first year of osteoporosis treatment were 44 (95% confidence interval [CI] 42 to 46) for alendronate, 40 (95% CI 38 to 43) for etidronate, 45 (95% CI 35 to 57) for risedronate, 32 (95% CI 27 to 37) for raloxifene, and 64 (95% CI 49 to 83) for strontium ranelate. After adjustment for age, Charlson index, and the number of comedications, pulmonary disease in men was associated with an increased use of TES (odds ratio [OR] = 1.48; 95% CI 1.17 to 1.86; p = 0.001). In women, malignant disease (OR = 1.27; 95% CI 1.02 to 1.60; p = 0.04) and pulmonary disease (OR = 1.32; 95% CI 1.07 to 1.62; p = 0.01) were significant predictors at 3 months and rheumatic diseases at 12 months (OR = 1.20; 95% CI 1.10 to 1.31; p < 0.001). There was no significant difference between the different drug classes (bisphosphonates versus nonbisphosphonates, alendronate versus nonalendronate-bisphosphonates) for risk of ocular inflammation, with age and the number of comedications being the only significant predictors. Hospital-treated uveitis (48 patients, or 0.05%) showed a similar trend. In conclusion, after initiation of treatment for osteoporosis, the risk of inflammatory eye reactions requiring TES is relatively low and not significantly different between bisphosphonate and nonbisphosphonate users. Patients with a rheumatic or pulmonary disease are at increased risk.

Inflammatory ocular adverse events with the use of oral bisphosphonates: a retrospective cohort study

BACKGROUND

There have been several published reports of inflammatory ocular adverse events, mainly uveitis and scleritis, among patients taking oral bisphosphonates. We examined the risk of these adverse events in a pharmacoepidemiologic cohort study.

METHODS

We conducted a retrospective cohort study involving residents of British Columbia who had visited an ophthalmologist from 2000 to 2007. Within the cohort, we identified all people who were first-time users of oral bisphosphonates and who were followed to the first inflammatory ocular adverse event, death, termination of insurance or the end of the study period. We defined an inflammatory ocular adverse event as scleritis or uveitis. We used a Cox proportional hazard model to determine the adjusted rate ratios. As a sensitivity analysis, we performed a propensity-score-adjusted analysis.

RESULTS

The cohort comprised 934,147 people, including 10,827 first-time users of bisphosphonates and 923,320 nonusers. The incidence rate among first-time users was 29/10,000 person-years for uveitis and 63/10,000 person-years for scleritis. In contrast, the incidence among people who did not use oral bisphosphonates was 20/10,000 person-years for uveitis and 36/10,000 for scleritis (number needed to harm: 1100 and 370, respectively). First-time users had an elevated risk of uveitis (adjusted relative risk [RR] 1.45, 95% confidence interval [CI] 1.25-1.68) and scleritis (adjusted RR 1.51, 95% CI 1.34-1.68). The rate ratio for the propensity-score-adjusted analysis did not change the results (uveitis: RR 1.50, 95% CI 1.29-1.73; scleritis: RR 1.53, 95% CI 1.39-1.70).

INTERPRETATION

People using oral bisphosphonates for the first time may be at a higher risk of scleritis and uveitis compared to people with no bisphosphonate use. Patients taking bisphosphonates must be familiar with the signs and symptoms of these conditions, so that they can immediately seek assessment by an ophthalmologist.

Safety of long-term bisphosphonate therapy for the management of osteoporosis

Drugs in the bisphosphonate class are the most commonly prescribed therapeutic agents for the treatment of osteoporosis. Prospective, randomized, placebo-controlled clinical trials have demonstrated efficacy in reducing fracture risk, with favourable safety profiles, in women with postmenopausal osteoporosis. However, long-term use in clinical practice has been associated with reports of undesirable events not previously recognized. These have included gastrointestinal intolerance, osteonecrosis of the jaw, atypical femur fractures, oesophageal cancer, atrial fibrillation and chronic musculoskeletal pain. Physicians must be alert to newly recognized safety concerns, understand the level of evidence supporting them and be able to effectively communicate the balance of expected benefit and potential risk to patients. Usually, post-marketing adverse events are first presented as case reports or observational studies with variable levels of supporting evidence for plausibility, pathophysiology and causality. Widespread coverage in the news media, which can be alarming to patients and their physicians, may not present a balanced view of the proven benefits, the uncertain risks of therapy and the relative magnitude of these events. There may be confusion about the risks associated with bisphosphonate use for the treatment of osteoporosis versus treatment of other conditions, such as cancer, which typically involves a very different patient population and different doses or frequency of drug administration. Often reports of possible adverse events do not provide information on the number of patients exposed to the drug in proportion to the reported adverse event, or do not describe the incidence of the adverse event in a comparator population not exposed to the drug. Gastrointestinal intolerance with oral bisphosphonates, and hypocalcaemia, acute phase reactions and renal toxicity with intravenous bisphosphonates are characterized by biological plausibility and demonstration of causality. Safety concerns with uncertain biological plausibility and unproven causality include osteonecrosis of the jaw, atypical femur fractures, oesophageal cancer and ocular inflammation. Suspected concerns that are unlikely to be causally related include atrial fibrillation and hepatotoxicity. When making the decision to use a bisphosphonate for the treatment of osteoporosis, the balance between benefit and potential risks according to clinical circumstances of each patient should be considered.

A case report: zoledronic acid-induced anterior uveitis

BACKGROUND

Bisphosphonates prevent bone loss by binding on active sites of bone remodeling and inhibiting osteoclast-mediated bone resorption. Zoledronic acid is recommended for patients with bone metastases from breast, prostate, and lung cancers.

OBJECTIVE

To report a case of anterior uveitis after the infusion of zoledronic acid.

CASE SUMMARY

A breast cancer patient with bone metastasis was admitted with pain, visual loss, hyperemia, and periorbital swelling in her right eye 24 h after the first dose of zoledronic acid. Biomicroscopic anterior segment examination of the right eye showed corneal keratic precipitates, ciliary injection, and moderate amount of cells in anterior chamber. With the diagnosis of right anterior uveitis, topical prednisolone acetate (1%) was started, and her symptoms completely resolved within 1 week. Use of the Naranjo probability scale indicated a probable relationship between uveitis and zoledronic acid therapy in our patient.

DISCUSSION

Uveitis is a rare complication of zoledronic acid. The mechanism is unclear. Proinflammatory cytokines such as TNF-alpha and IL-6 may also play a role in pathogenesis of zoledronic acid-related uveitis.

CONCLUSION

Zoledronic acid may be associated with inflammatory eye diseases and result in serious ocular damage.

Ocular Adverse Effects Associated with Systemic Medications

This article reviews several retrospective case series and reported adverse events regarding common ocular adverse effects related to systemic therapy. It is not intended as a comprehensive summary of these well described adverse drug reactions, nor is it intended to cover the complete spectrum of all ocular adverse effects of systemic therapy. Many systemic drugs may produce ocular toxicity, including bisphosphonates, topiramate, vigabatrin, isotretinoin and other retinoids, amiodarone, ethambutol, chloroquine and hydroxychloroquine, tamoxifen, quetiapine, cyclo-oxygenase (COX)-2 inhibitors, erectile dysfunction agents and some herbal medications. For this review, the certainty of the adverse effect profile of each medication was evaluated according to the WHO Causality Assessment Guide.A certain relationship has been established for pamidronate and alendronate as causes of scleritis, uveitis, conjunctivitis and blurred vision. Topiramate has been established as adversely causing symptoms consistent with acute angle-closure glaucoma, typically bilateral. Vigabatrin has been shown to cause bilateral irreversible visual field defects attributed to underlying medication-induced retinal pathology. Isotretinoin should be considered in the differential diagnosis of any patient with pseudotumour cerebri. Patients taking amiodarone and hydroxychloroquine should be monitored and screened regularly for development of optic neuropathy and maculopathy, respectively. Sildenafil has been reported to cause several changes in visual perception and is a possible, not yet certain, cause of anterior ischaemic optic neuropathy. Patients taking tamoxifen should also be monitored for development of dose-dependent maculopathy and decreased colour vision. COX-2 inhibitors should be included in the differential diagnosis of reversible conjunctivitis. Several herbal medications including canthaxanthine, chamomile, datura, Echinacea purpurea, Ginkgo biloba and liquorice have also been associated with several ocular adverse effects. It is the role of all healthcare professionals to detect, treat and educate the public about adverse reactions to medications as they are an important health problem.

Management of the adverse effects associated with intravenous bisphosphonates

Intravenous bisphosphonates are widely used to treat hypercalcemia and to reduce skeletal-related morbidity among cancer patients. However, serious complications, generally occurring in less than 2% of patients participated in phase III clinical trials, including acute systemic inflammatory reaction, ocular inflammation, renal failure, nephrotic syndrome, electrolyte imbalance, and osteonecrosis of the maxilla and mandible have all been increasingly reported. Yet, strategies to deal with these complications are becoming clear. Acute systemic inflammatory reaction is often self-limited and becomes less intense during subsequent treatments. For patients who develop ocular symptoms, prompt ophthalmologic evaluation is crucial to determine the safety of a subsequent bisphosphonate therapy. Patients who receive long-term pamidronate should be evaluated at intervals for early sign of nephritic syndrome as timely cessation of the agent may result in a full recovery. To reduce the risk of severe electrolyte abnormalities, particularly hypocalcemia, correcting any pre-treatment electrolyte abnormality and supplementing vitamin D and calcium may be helpful. Finally, to reduce the risk of osteonecrosis of the maxilla and mandible, obtaining a full dental evaluation before treatment and avoidance of invasive dental procedures is suggested. The three commonly used intravenous bisphosphonates (pamidronate, zoledronic acid, and ibandronate), are generally safe; ibandronate has to date been the least reported to be associated with renal side effects. As clinical indications of intravenous bisphosphonates continue to expand, prescribing clinicians should be familiar with these possible adverse effects and discuss them with patients before commencing or continuing on therapy.

Ophthalmological Events in Patients Receiving Risedronate

BACKGROUND

In the UK, the nitrogen bisphosphonate risedronate is licensed for the prevention and treatment of osteoporosis and corticosteroid-induced osteoporosis in postmenopausal women. It is also licensed for the treatment of Paget's disease. During a prescription-event monitoring (PEM) study on risedronate we noted a number of ophthalmological events. Recently, case reports of ophthalmological adverse drug reactions in patients taking bisphosphonates were published in the medical literature. The aim of this study was to further evaluate the association of ophthalmological events reported in relation to risedronate treatment during a PEM study on the drug.

METHODS

An observational cohort study (PEM study) was conducted in England between September 2000 and June 2002. General practitioners (GPs) were asked for follow-up information on selected events. Events followed up were classified as either 'probably', 'possibly' or 'unlikely' to be related to risedronate, using a modified WHO classification. If insufficient information was obtained on the follow-up questionnaire, the cases were categorised as 'unassessable'.

RESULTS

Of the total PEM study cohort of 13 643 patients, 11 156 (82%) were females and 2398 (18%) were males. We received 359 reports of ophthalmological events in 313 patients during the entire study period. Of these we followed up 178 events in 178 patients. Nineteen events in 19 patients were assessed as possibly or probably related to risedronate. The age range for these patients was 50-92 years and the time to onset ranged from 7 days to 5 months. Dry eye (six reports), sore eye (five reports) and conjunctivitis (three reports) were the most frequently reported ophthalmological events assessed as probably or possibly related to risedronate therapy. GPs also reported several other inflammatory conditions of the eye, amongst them two events each of iritis and episcleritis as well as one of keratitis. However, the information received on follow up of these events was insufficient to make causality assessments.

CONCLUSION

Patients receiving risedronate can present with a variety of signs and symptoms affecting the eye with different degrees of severity. Patients may present after the first month of treatment. Doctors should have an increased awareness of possible ophthalmological adverse drug reactions in patients receiving this drug, which may affect the eyesight in a population at increased risk of fracture if they fall.

Unilateral anterior uveitis complicating zoledronic acid therapy in breast cancer

Background

Zoledronic acid is very widely used in patients with metastatic bone disease and osteoporosis. Only one case of bilateral uveitis was recently reported related to its use.

Case presentation

We report the first case of severe unilateral anterior uveitis in a patient with breast cancer and an intraocular lens. Following zoledronic acid infusion, the patient developed severe and dramatic right eye pain with decreased visual acuity within 24 hours and was found to have a fibrinous anterior uveitis of moderate severity The patient was treated with topical prednisone and atropine eyedrops and recovered slowly over several months.

Conclusion

Internists, oncologists, endocrinologists, and ophtalmologists should be aware of uveitis as a possible complication of zoledronic acid therapy. Patients should be instructed to report immediately to their physicians and treatment with topical prednisone and atropine eyedrops should be instituted immediately at the onset of symptoms. This report documents anterior uveitis as a complication of zoledronic acid therapy. This reaction could be an idiosyncratic one but further research may shed more light on the etiology.

Bisphosphonate-associated Scleritis: A Case Report and Review

An 86-year-old female was treated for osteoporosis with alendronate, an aminobisphosphonate. Six weeks after alendronate therapy began, scleritis developed in the patient's right eye. The alendronate was discontinued, and, with the administration of prednisone, the symptoms of scleritis fully resolved. Rechallenge resulted in recurrence of the symptoms. Bisphosphonates are commonly used in the management of osteoporosis and are generally safe agents. Rarely, they have been linked with ocular inflammation. This case report reviews the literature on the ocular effects of bisphosphonates and discusses a possible mechanism for the association.

Bisphosphonate treatment of osteoporosis

Bisphosphonates represent the agents of choice for most patients with osteoporosis. They are the best studied of all agents for the prevention of bone loss and reduction in fractures. They increase BMD, primarily at the lumbar spine, but also at the proximal femur. In patients who have established osteoporosis, bisphosphonates reduce the risk of vertebral fractures, and are the only agents in prospective trials to reduce the risk of hip fractures and other nonvertebral fractures. Bisphosphonates reduce the risk of fracture quickly. The risk of radiographic vertebral deformities is reduced after 1 year of treatment with risedronate [68]. The risk of clinical vertebral fractures is reduced after 1 year of treatment with alendronate [69] and just 6 months' treatment with risedronate [157]. The antifracture effect of risedronate has been shown to continue through 5 years of treatment [158]. Alendronate and risedronate are approved by the FDA for prevention of bone loss in recently menopausal women, for treatment of postmenopausal osteoporosis, and for prevention (risedronate) and treatment (alendronate and risedronate) of glucocorticoid-induced osteoporosis. Alendronate is also approved for treatment of osteoporosis in men. Other bisphosphonates (etidronate for oral use, pamidronate and zoledronate for intravenous infusion) are also available and can be used off label for patients who cannot tolerate approved agents. Although bisphosphonates combined with estrogen or raloxifene produce greater gains in bone mass compared with single-agent treatment, the use of two antiresorptive agents in combination cannot be recommended because the benefit on fracture risk has not been demonstrated and because of increased cost and side effects.

Scleritis and other ocular side effects associated with pamidronate disodium

PURPOSE

To evaluate reported cases of scleritis and other ocular side effects associated with pamidronate disodium, with emphasis on previously unreported cases of scleritis.

DESIGN

Observational case series.

METHODS

Case reports from the National Registry of Drug-Induced Ocular Side Effects (Casey Eye Institute), the Food and Drug Administration, the World Health Organization, and the literature were reviewed to determine possible adverse ocular side effects associated with pamidronate disodium. The World Health Organization's Causality Assessment Guide was used to categorize an adverse drug reaction.

RESULTS

Seventeen cases of unilateral scleritis and one case of bilateral scleritis occurred, usually within 6 hours to 2 days after intravenous pamidronate disodium. Six patients had positive rechallenge testing with the scleritis occurring after a repeat drug exposure. Other ocular side effects with positive rechallenge data, associated with pamidronate disodium, include blurred vision, nonspecific conjunctivitis, ocular pain, bilateral anterior uveitis, and episcleritis.

CONCLUSIONS

This is the first report, with rechallenge data, of any drug causing scleritis. Pamidronate disodium can cause vision-threatening diseases, which may require discontinuing the drug in some uveitis cases and, in this series, all cases of scleritis.

The role of disodium pamidronate in the management of bone pain due to malignancy

A number of controlled studies have recently demonstrated the role of disodium pamidronate in the prevention of skeletal complications in patients with metastatic bone disease due to breast cancer and multiple myeloma. They have also shown that it relieves pain and is well tolerated. The aim of this open prospective study was to evaluate the acceptability of a new schedule of pamidronate infusion and to assess pain, analgesic consumption and the Karnofsky Performance Status (KPS) in patients with metastatic bone pain treated with pamidronate in association or not with chemotherapy, radiotherapy, and hormone therapy. Patients with different types of cancer and at least one painful bone metastasis were treated with two cycles of 60 mg intravenous (iv) pamidronate weekly for three consecutive doses, with a 3-week interval between the two cycles (six infusions over 7 weeks), followed by one infusion every 3 weeks for a total of 24 infusions. Two hundred patients were enrolled in the study, of whom 94 received at least the first six infusions; 25 patients received all 24 infusions. Pamidronate was well tolerated in the majority of the patients both during the first six infusions and during the whole study period. In the patients under study, pain intensity decreased compared with T0 after the first two infusions (second week of treatment). The mean equivalent daily dose of oral morphine required ranged from 21.5 to 41.5 mg/day and was low and stable during the study. For the patients who remained in the study, the KPS remained around 70 during the whole treatment period and intrasubject analysis showed a substantial stability of the KPS within each subject. A first fracture occurred within 321 days in 25% of the whole population under study. Pamidronate represents a further valid therapy to add to an already consolidated list of therapies such as radiotherapy, chemotherapy, hormone therapy and orthopaedic intervention in the pain management of patients with bone metastases. Future studies are necessary to evaluate the role of pamidronate and the appropriate schedule in patients with advanced or terminal cancer who are no longer being treated with oncological therapies.

Treatment of osteoporosis with bisphosphonates

Bisphosphonates are safe and effective agents for treatment and prevention of osteoporosis. Alendronate and risedronate are the best studied of all agents for osteoporosis in terms of efficacy and safety. They increase bone mass. In patients who have established osteoporosis, they reduce the risk of vertebral fractures. They are the only agents shown in prospective trials to reduce the risk of hip fractures and other nonvertebral fractures. They are approved by the US FDA for prevention of bone loss in recently menopausal women, for treatment of postmenopausal osteoporosis, and for management of glucocorticoid-induced bone loss. Other bisphosphonates (e.g., etidronate for oral use, pamidronate for intravenous infusion) are also available and can be used off-label for patients who cannot tolerate approved agents. Bisphosphonates combined with estrogen produce greater gains in bone mass compared with either agent used alone; whether there is a greater benefit of combination therapy on fracture risk is not clear. Combining a bisphosphonate with raloxifene or calcitonin is probably safe, although data on effectiveness are lacking.

Using bisphosphonates to control the pain of bone metastases: evidence-based guidelines for palliative care

This work was undertaken by the Science Committee of the Association for Palliative Medicine of Great Britain and Ireland (APM) as a demonstration project in developing clinical guidelines relevant to palliative care from a pragmatic approach to literature review and grading of clinical evidence. CANCERLIT and Embase were searched for relevant papers written in English, published since 1980. Each study identified was rated against agreed criteria for levels of evidence. Most studies were not specifically designed to define speed of response, and were not undertaken in palliative care patients. Thus, careful reading and grading of each study was necessary. Sufficient evidence was identified to make recommendations for clinical practice in a palliative care population of patients, and areas for future research have been identified. Bisphosphonates appear to have a role in managing pain from metastases which has been refractory to conventional analgesic management and where oncological or orthopaedic intervention is delayed or inappropriate.

Treatment of osteoporosis with bisphosphonates

Several bisphosphonates are effective for preventing bone loss associated with estrogen deficiency, glucocorticoid treatment, and immobilization, and for at least partially reversing bone loss in patients with postmenopausal osteoporosis and steroid-induced osteoporosis. The most promising of these agents are etidronate, alendronate, risedronate, and ibandronate. These drugs should have an important role in the prevention and treatment of osteoporosis; however, more research is needed regarding optimal doses and regimens (continuous versus intermittent, oral versus parenteral), comparisons with other agents, and their use in combination with other agents.