Etidronate for treating and preventing postmenopausal osteoporosis

Effects of increasing age, dosage, and duration of PTH treatment on BMD increase--a meta-analysis

We studied the effects of increasing age, dosage, and duration of parathyroid hormone (PTH) treatment on changes in bone mineral density (BMD). Randomized placebo controlled trials on PTH treatment in men or women were retrieved from PubMed (1951 to present), Web of Science (1945 to present), or Embase (1974 to present). The search date was November 16, 2010. All studies comparing PTH treatment to either placebo or antiresorptive drugs--for example, bisphosphonates or hormone replacement therapy--were included. A total of 214 studies were identified in the initial search, and 15 of these trials were included. By metaregression analysis, we found that the increase in spine BMD (Z-score) after PTH treatment was blunted by increasing age (R(2) = 0.27; 2p = 0.01, slope -0.023 Z-scores per year, 11 studies). By increasing PTH dosage (μg/d), spine BMD increased significantly (2p = 0.002) with a slope of +0.011 Z-scores/μg/d of teriparatide. Furthermore, the duration of treatment was positively correlated to spine BMD (P < 0.001) with a slope of +0.043 Z-score for each extra month of treatment. We evaluated the BMD effect in hips and found no age dependency (R(2) = 0.04; P = 0.66; 8 studies). However, for the spine, we found a significant relation to daily dosage (P = 0.011), Z-score coefficient 0.0051 ± 0.0020 (2p < 0.01). The treatment duration also correlated positively by a Z-score coefficient of 0.0170 ± 0.0053, 2p < 0.01 per extra month of treatment. PTH treatment alone seems to be able to improve BMD significantly. However, the BMD increase was significantly lower with increasing age in the spine. No age dependency was observed in the hips. In general the effect of treatment was improved with increasing dosage and duration of treatment from 6 to 36 months.

The evidence for efficacy of osteoporosis treatment in men with primary osteoporosis: a systematic review and meta-analysis of antiresorptive and anabolic treatment in men

Purpose. Fragility fractures in men constitute a major worldwide public health problem with a life-time risk of 13%. It cannot be directly inferred that antiosteoporotic drugs effective in women have the same effect in men. Our aim was to appraise the existing evidence for efficacy of osteoporosis treatment in men. Methods. This study was a systematic review of the published literature on the clinical efficacy of medical osteoporosis therapy in the reduction of fracture risk in men (age > 50 years). Studies included were randomised, placebo-controlled trials of men. Results. Five BMD studies of antiresorptive treatment were included. All studies showed an increase in BMD, but there was only a nonsignificant trend in the reduction of clinical fractures. Three BMD studies of anabolic treatment with teriparatide were also included. These showed a significant mean increase in spine BMD and for vertebral fractures a non-significant trend towards a reduction was seen. Conclusion. The evidence of medical osteoporosis treatment in men is scant and inconclusive due to the lack of prospective RCT studies with fracture prevention as primary end point. So far, all evidence is based on BMD increases in small RCT studies showing BMD increases comparable to those reported in postmenopausal women.

Fragility fractures and the osteoporosis care gap in women: the Canadian Multicentre Osteoporosis Study

Canadian women over 50 years old were studied over a 10-year period to see if those who sustained a fracture (caused by minimal trauma) were receiving the recommended osteoporosis therapy. We found that approximately half of these women were not being treated, indicating a significant care gap in osteoporosis treatment.

INTRODUCTION

Prevalent fragility fracture strongly predicts future fracture. Previous studies have indicated that women with fragility fractures are not receiving the indicated treatment. We aimed to describe post fracture care in Canadian women using a large, population-based prospective cohort that began in 1995-1997.

METHODS

We followed 5,566 women over 50 years of age from across Canada over a period of 10 years in the Canadian Multicentre Osteoporosis Study. Information on medication use and incident clinical fragility fractures was obtained during a yearly questionnaire or interview and fractures were confirmed by radiographic/medical reports.

RESULTS

Over the 10-year study period, 42-56% of women with yearly incident clinical fragility fractures were not treated with an osteoporosis medication. During year 1 of the study, 22% of the women who had experienced a fragility fracture were on treatment with a bisphosphonate and 26% were on hormone therapy (HT). We were not able to differentiate HT use for menopause symptoms vs osteoporosis. Use of bisphosphonate therapy increased over time; odds ratio (OR) for use at year 10 compared to use at year 1 was 3.65 (95% confidence interval (CI) 1.83-7.26). In contrast, HT use declined, with an OR of 0.07 (95%CI 0.02-0.24) at year 10 compared to year 1 of the study.

CONCLUSION

In a large population-based cohort study, we found a therapeutic care gap in women with osteoporosis and fragility fractures. Although bisphosphonate therapy usage improved over time, a substantial gap remains.

[Austrian guidance for the pharmacological treatment of osteoporosis in postmenopausal women--update 2009]

Osteoporosis is a systemic skeletal disease characterized by diminished bone mass and deterioration of bone microarchitecture, leading to increased fragility and subsequent increased fracture risk. Therapeutic measures therefore aim at reducing individual fracture risk. In Austria, the following drugs, all of which have been proven to reduce fracture risk, are currently registered for the treatment of postmenopausal osteoporosis: alendronate, risedronate, etidronate, ibandronate, raloxifene, teriparatide (1-34 PTH), 1-84 PTH, strontium ranelate and salmon calcitonin. Fluorides are still available, but their role in daily practice has become negligible. Currently, there is no evidence that a combination of two or more of these drugs could improve anti-fracture potency. However, treatment with PTH should be followed by the treatment with an anticatabolic drug such as bisphosphonates. Calcium and vitamin D constitute an important adjunct to any osteoporosis treatment.

Etidronate for the primary and secondary prevention of osteoporotic fractures in postmenopausal women

BACKGROUND

Osteoporosis is an abnormal reduction in bone mass and bone deterioration leading to increased fracture risk. Etidronate belongs to the bisphosphonate class of drugs which act to inhibit bone resorption by interfering with the activity of osteoclasts.

OBJECTIVES

To assess the efficacy of etidronate in the primary and secondary prevention of osteoporotic fractures in postmenopausal women.

SEARCH STRATEGY

We searched CENTRAL, MEDLINE and EMBASE for relevant randomized controlled trials published between 1966 to 2007.

SELECTION CRITERIA

Women receiving at least one year of etidronate for postmenopausal osteoporosis were compared to those receiving placebo and/or concurrent calcium/vitamin D. The outcome was fracture incidence.

DATA COLLECTION AND ANALYSIS

Study selection and data abstraction was done in duplicate. Meta-analysis of fracture outcomes was performed with data presented as relative risks and a relative change greater than 15% was considered clinically important. Study quality was assessed through the reporting of allocation concealment, blinding and withdrawals.

MAIN RESULTS

Eleven studies representing a total of 1248 patients were included in the review.A significant 41% relative risk reduction (RRR) in vertebral fractures across eight studies (RR 0.59, 95% CI 0.36 to 0.96) was found. The six secondary prevention trials demonstrated a significant RRR of 47% in vertebral fractures (RR 0.53, 95% CI 0.32 to 0.87) and a 5% absolute risk reduction (ARR); compared with the pooled result for the two primary prevention trials (RR 3.03, 95% CI 0.32 to 28.44), which was not significant. There were no statistically significant risk reductions for non-vertebral (RR 0.98, 95% CI 0.68 to 1.42), hip (RR 1.20, 95% CI 0.37 to 3.88) or wrist fractures (RR 0.87, 95% CI: 0.32 to 2.36). For adverse events, no statistically significant differences were found in the included studies. However, observational data has led to concerns regarding potential risk for upper gastrointestinal injury.

AUTHORS' CONCLUSIONS

Etidronate, at 400 mg per day, demonstrated a statistically significant and clinically important benefit in the secondary prevention of vertebral fractures. No statistically significant reductions in vertebral fractures were observed when it was used for primary prevention. In addition, no statistically significant reductions in non-vertebral, hip, or wrist fractures were found, regardless of whether etidronate was used for primary or secondary prevention. The level of evidence for all outcomes is Silver (www.cochranemsk.org.).

Basic and clinical aspects of osteoporosis in inflammatory bowel disease

Low bone mineral density and the increased risk of fracture in gastrointestinal diseases have a multifactorial pathogenesis. Inflammatory bowel disease (IBD) has been associated with an increased risk of osteoporosis and osteopenia and epidemiologic studies have reported an increased prevalence of low bone mass in patients with IBD. Certainly, genetics play an important role, along with other factors such as systemic inflammation, malnutrition, hypogonadism, glucocorticoid therapy in IBD and other lifestyle factors. At a molecular level the proinflammatory cytokines that contribute to the intestinal immune response in IBD are known to enhance bone resorption. There are genes influencing osteoblast function and it is likely that LRP5 may be involved in the skeletal development. Also the identification of vitamin D receptors (VDRs) and some of its polymorphisms have led to consider the possible relationships between them and some autoimmune diseases and may be involved in the pathogenesis through the exertion of its immunomodulatory effects during inflammation. Trying to explain the physiopathology we have found that there is increasing evidence for the integration between systemic inflammation and bone loss likely mediated via receptor for activated nuclear factor kappa-B (RANK), RANK-ligand, and osteoprotegerin, proteins that can affect both osteoclastogenesis and T-cell activation. Although glucocorticoids can reduce mucosal and systemic inflammation, they have intrinsic qualities that negatively impact on bone mass. It is still controversial if all IBD patients should be screened, especially in patients with preexisting risk factors for bone disease. Available methods to measure BMD include single energy x-ray absorptiometry, DXA, quantitative computed tomography (QCT), radiographic absorptiometry, and ultrasound. DXA is the establish method to determine BMD, and routinely is measured in the hip and the lumbar spine. There are several treatments options that have proven their effectiveness, while new emergent therapies such as calcitonin and teriparatide among others remain to be assessed.

Are Oral Bisphosphonates Effective in Improving Lumbar Bone Mineral Density in Breast Cancer Survivors With Osteopenia or Osteoporosis?

OBJECTIVE

Breast cancer survivors with osteoporosis or osteopenia are commonly encountered in primary care and gynaecology practices. Our objective was to determine whether treatment with oral bisphosphonates (alendronate or cyclic etidronate) was more effective than calcium with vitamin D in improving lumbar spine bone mineral density (BMD) within one year in breast cancer survivors.

METHODS

Breast cancer survivors with at least one year of clinical follow-up were identified from the prospective observational Canadian Database of Osteoporosis and Osteopenia (CANDOO). Analysis of covariance was used to examine the effects of bisphosphonate therapy on change in lumbar spine BMD at one year compared with the effects of calcium with vitamin D (analysis adjusted for baseline L2-L4 BMD, current tamoxifen use, number of prevalent vertebral fractures [VFs], and time since diagnosis of breast cancer, and age).

RESULTS

Eighteen patients took calcium and vitamin D, 25 took cyclic etidronate, and 27 took oral alendronate. Adjusted one-year BMD increases for alendronate and cyclic etidronate compared to calcium and vitamin D were as follows: alendronate 4.53% (95% confidence interval [CI] 1.26%, 7.81%, P = 0.008), and cyclic etidronate 1.85% (-1.55%, 5.25%, P = 0.280). BMD increases were significantly greater in patients with prevalent VF compared to those without VF (P = 0.025). In contrast, time since diagnosis of breast cancer was significantly associated with a decrease in BMD (P = 0.002). We were unable to detect any effect of current tamoxifen use, baseline lumbar spine BMD, or age on changes in BMD at one year.

CONCLUSION

Treatment with alendronate was associated with significantly greater improvements in lumbar spine BMD within one year in breast cancer survivors when compared with treatment with cyclic etidronate or calcium and vitamin D.

Outcome following a second hip fracture

Hip fracture has a significant impact on medical resources and patient morbidity and mortality. Few patients admitted with a hip fracture are considered for prophylactic measures aimed at the reduction of further fracture risk. Currently, 10-13% of patients will later sustain a second hip fracture. In considering the possible role of prophylactic measures in the prevention of second hip fracture, we investigated whether second hip fracture has a significant further impact on patients' mobility and social independence. We also sought to identify a pattern to second hip fracture that may allow targeting of those patients who are most likely to benefit from currently available prophylactic measures. We undertook a retrospective review of 49 consecutive patients admitted with a second hip fracture between August 1999 and September 2000. Fewer patients maintained their ability to walk independently after the second fracture than did so after the first (53 and 91% respectively, P<0.0005). Following second hip fracture, patients' level of mobility determined their future social independence. Older patients and those with a history of multiple falls had a shorter time interval between fractures. Second hip fracture has a significant further impact on patients' mobility and social independence. Younger patients and those without a history of multiple falls are most likely to benefit from medical prophylaxis.

Bisphosphonates

Bisphosphonates now occupy a prominent position among therapeutic options for the prevention and treatment of various forms of osteoporosis. Their clinical profile of bone-specific efficacy, rapid response, protection from both spine and hip fractures in patients with osteoporosis, and excellent tolerability is all that can be expected of an anti-remodeling drug. Even in the era of anabolic agents, bisphosphonates will continue to be important treatment options. It is not possible to compare or contrast the clinical effectiveness of the various bisphosphonates on the basis of existing data. Despite marked differences in the in vitro potency of drugs, the clinical responses to each of the bisphosphonates discussed above are similar. New bisphosphonates may not be more effective but will provide different tolerability profiles and different routes of administration, thereby increasing the number of patients in whom bisphosphonates can be used. Having these effective agents challenges clinicians to identify the most appropriate patients for bisphosphonate use and to develop strategies to improve acceptance of and adherence to these useful agents.