Biomedical subjects

Paul D Miller

Publications and source records attributed to Paul D Miller.

At least 19 recordsLinked to original sources

PubMed2006

White-rot fungi demonstrate first biodegradation of phenolic resin.

Phenolic resins, phenol-formaldehyde polymers previously thought to be nonbiodegradable, are produced at an annual rate of 2.2 million metric tons in the United States for many industrial and commercial applications. Three independent lines of evidence established their biodegradability with the white-rot fungus Phanerochaete chrysosporium. Chromatic transformation of growth medium (yellow to pink) indicated initial biodegradation of the resin 3 days after inoculation. A degradation product, 13C-labeled phenol, was detected with gas chromatography-mass spectroscopy. Scanning electron micrographs revealed physical evidence of degradation. This is the first demonstrated biodegradation of these phenol-formaldehyde polymers and stands as a platform for investigation into bioremediation and biorecycling of phenolic resins.

Biodegradation, Environmental↗

PubMed2006

Bone mineral density in women aged 25-35 years receiving depot medroxyprogesterone acetate: recovery following discontinuation.

INTRODUCTION: This 7-year, prospective, matched-cohort, clinical study evaluated the effects of intramuscular depot medroxyprogesterone acetate (DMPA) (150 mg/mL) on bone mineral density (BMD) in women aged 25-35 years. METHODS: Bone mineral density changes in new DMPA-IM users (n=248) were compared with those in women using nonhormonal contraception (n=360) for up to 240 weeks of treatment and 96 weeks of posttreatment follow-up (in subjects receiving >or=1 dose). RESULTS: At week 240 of treatment, mean percentage changes from baseline in DMPA-IM vs. nonhormonal subjects were: -5.16% (n=21) vs. +0.19% (n=65), total hip (p<.001); -5.38% (n=33) vs. +0.43% (n=105), lumbar spine (p<.001). At week 96 posttreatment, these values were: -0.20% (n=25) vs. +0.84% (n=43), total hip (p=.047); -1.19% (n=41) vs. +0.47% (n=66), lumbar spine (p=.017). CONCLUSIONS: These results show BMD declines during DMPA-IM use; following discontinuation, significant increases in BMD occur through 96 weeks posttreatment.

Adult↗

PubMed2006

Application of the 1994 WHO classification to populations other than postmenopausal Caucasian women: the 2005 ISCD Official Positions.

In 2003, the International Society for Clinical Densitometry (ISCD) developed Official Positions regarding the applicability of the World Health Organization (WHO) classification of bone mineral density to populations other than postmenopausal women. However, these prior Official Positions do not fully address bone mineral density reporting in females prior to menopause, men, and non-whites. During the 2005 ISCD Position Development Conference, members of the ISCD Expert Panel in conjunction with the ISCD Scientific Advisory Committee re-addressed these topics and, based upon stringent reviews of best available data, developed ISCD Official Positions that provide greater specificity and clarification with respect to the following: (1) the utility of the term 'osteopenia'; (2) utilization of T- and Z-scores for bone mineral density reporting; (3) when to apply the WHO densitometric classification; and (4) which normative database(s) should be used for non-white individuals. Briefly, the term "osteopenia" is retained, but 'low bone mass' or 'low bone density' is preferred. Z-scores, not T-scores, are preferred in females prior to menopause and males under age 50. In these individuals, a Z-score of -2.0 or lower is defined as "below the expected range for age" and a Z-score above -2.0 is "within the expected range for age." T-scores are preferred and the WHO classification is applicable for postmenopausal women and men age 50 and older. These Official Positions, rationale and evidence are discussed in the following report.

Absorptiometry, Photon↗

PubMed2006

New or worsening lumbar spine vertebral fractures increase lumbar spine bone mineral density and falsely suggest improved skeletal status.

Changes in lumbar spine bone mineral density (BMD) are determined by follow-up dual-energy x-ray absorptiometry (DXA) assessments. Inclusion of new or worsening vertebral fractures in follow-up measurements may increase BMD. To test this hypothesis, we examined pooled data from the placebo groups of two clinical trials that involved postmenopausal women with osteoporosis. DXA measurements of lumbar spine BMD, bone mineral content (BMC), and area were obtained at baseline and at two years in the Multiple Outcomes of Raloxifene Evaluation (MORE) Trial and at baseline and study endpoint in the Fracture Prevention Trial. In these trials, fractured vertebrae identified by expert radiologists during posterioranterior (PA) spine DXA assessment were excluded from the BMD assessment. Lateral spine radiographs were graded using a semi-quantitative (SQ) scale. Most new or worsening vertebral fractures (84%) diagnosed from lateral spine radiographs were not identified by PA spine DXA. While the follow-up BMD of vertebrae without new or worsening fractures did not change significantly, each unit increase in SQ grade was associated with an approximate 7.0% increase in the BMD of affected vertebrae (p < 0.001). Increases in BMD were highly correlated with increases in BMC (r = 0.87, p < 0.001). Inclusion of new or worsening vertebral fractures increased PA spine BMD measurements at follow-up, with the impact being related to the magnitude of change in SQ score. It is difficult to reliably identify vertebral fractures from PA spine DXA assessments. Inclusion of new or worsening vertebral fractures in follow-up DXA measurements may falsely suggest an improvement in spine BMD. Our suggestion is to perform lateral spine imaging concurrently with any assessment of PA spine BMD in patients who, in the opinion of the health care provider, may have vertebral fractures.

Absorptiometry, Photon↗

PubMed2006

Standards for performing DXA in individuals with secondary causes of osteoporosis.

This document addresses skeletal health assessment in individuals with secondary causes of osteoporosis. Recommendations are based on consensus of the Canadian Panel of the International Society for Clinical Densitometry and invited international experts. Bone mineral density (BMD) testing in these populations is performed in conjunction with careful evaluation of the disease state contributing to bone loss and increased fragility fracture risk, as well as assessment of other contributing risk factors for fracture. The presence of secondary causes of bone loss may further increase the risk of fracture independently of BMD and may necessitate earlier pharmacologic intervention. Dual-energy X-ray absorptiometry is indicated in the initial workup of secondary causes of osteoporosis. The BMD fracture risk relationship is not known for individuals with chronic renal failure (CRF). The BMD testing in this population may be normal in the presence of skeletal fragility, and quantitative bone histomorphometry is better at evaluating skeletal status than BMD in CRF. Dual-energy X-ray absorptiometry is a valuable tool in assessing skeletal health in individuals with secondary causes of osteoporosis.

Absorptiometry, Photon↗

PubMed2006

Denosumab in postmenopausal women with low bone mineral density.

BACKGROUND: Receptor activator of nuclear factor-kappaB ligand (RANKL) is essential for osteoclast differentiation, activation, and survival. The fully human monoclonal antibody denosumab (formerly known as AMG 162) binds RANKL with high affinity and specificity and inhibits RANKL action. METHODS: The efficacy and safety of subcutaneously administered denosumab were evaluated over a period of 12 months in 412 postmenopausal women with low bone mineral density (T score of -1.8 to -4.0 at the lumbar spine or -1.8 to -3.5 at the proximal femur). Subjects were randomly assigned to receive denosumab either every three months (at a dose of 6, 14, or 30 mg) or every six months (at a dose of 14, 60, 100, or 210 mg), open-label oral alendronate once weekly (at a dose of 70 mg), or placebo. The primary end point was the percentage change from baseline in bone mineral density at the lumbar spine at 12 months. Changes in bone turnover were assessed by measurement of serum and urine telopeptides and bone-specific alkaline phosphatase. RESULTS: Denosumab treatment for 12 months resulted in an increase in bone mineral density at the lumbar spine of 3.0 to 6.7 percent (as compared with an increase of 4.6 percent with alendronate and a loss of 0.8 percent with placebo), at the total hip of 1.9 to 3.6 percent (as compared with an increase of 2.1 percent with alendronate and a loss of 0.6 percent with placebo), and at the distal third of the radius of 0.4 to 1.3 percent (as compared with decreases of 0.5 percent with alendronate and 2.0 percent with placebo). Near-maximal reductions in mean levels of serum C-telopeptide from baseline were evident three days after the administration of denosumab. The duration of the suppression of bone turnover appeared to be dose-dependent. CONCLUSIONS: In postmenopausal women with low bone mass, denosumab increased bone mineral density and decreased bone resorption. These preliminary data suggest that denosumab might be an effective treatment for osteoporosis. (ClinicalTrials.gov number, NCT00043186.).

Alendronate↗

PubMed2006

Guidelines for the diagnosis of osteoporosis: T-scores vs fractures.

The development of bone mineral densitimometry methodologies, especially central dual energy X-ray absorptiometry (DXA) methods have allowed this quantitative tool to be used to diagnose osteoporosis before the first fragility fracture has occurred. The World Health Organization osteoporosis working group set the stage for the BMD cut-off criteria development. The wide application of DXA has brought the treatment of osteoporosis to the primary care level, a very necessary step if this increasingly prevalent disease is to have a decline in its incidence. The most difficult osteoporosis cases, for which there are many and their associated difficult DXA results and interpretation will always require specialists' involvement. In particular, the embracement of the WHO absolute fracture risk validated project will take DXA to a much greater level of value in making management decisions. In particular, the WHO absolute risk data will allow physicians, health-economic policy makers, and payors of medical services to come closer together to decide which patients are at a level of unacceptable fracture risk that justifies treatment intervention. The implementation of this validated project will also remove the unacceptable subjective computer printouts on DXA reports that often lead to the over-treatment of low risk patients and at times the under-treatment of high risk patients. The evolution of the clinical interpretation of bone densitometry has been a work in progress. Challenges in the clinical measurement of bone strength remain and will also evolve. The field of osteoporosis has grown with the use of DXA and will continue to embrace this technology as other technologies to measure fracture risk become applied in clinical practice.

Absorptiometry, Photon↗

PubMed2006

Change in lumbar spine BMD and vertebral fracture risk reduction in teriparatide-treated postmenopausal women with osteoporosis.

UNLABELLED: Increases in lumbar spine BMD account for 30-41% of the vertebral fracture risk reduction with teriparatide treatment. The remaining fracture risk reduction is caused by improvements in non-BMD determinants of bone strength. INTRODUCTION: Changes in BMD account for a small percentage of the fracture risk reduction seen in patients treated with antiresorptive drugs. The relationship between changes in lumbar spine BMD and vertebral fracture risk reduction with teriparatide treatment has not been assessed. MATERIALS AND METHODS: The relationship between spine BMD and the risk of new vertebral fractures after teriparatide treatment was assessed using data from the Fracture Prevention Trial. Postmenopausal women with osteoporosis (n = 1637) were randomized to placebo or teriparatide 20 or 40 microg/day for a median of 19 months. Spine BMD was assessed at baseline and 18 months. Vertebrae whose fracture status changed during the trial were removed from the calculation of BMD. Baseline and endpoint lateral spine radiographs were assessed using a visual semiquantitative technique. RESULTS: Both the baseline and change in spine BMD were contributors to vertebral fracture risk. The mean spine BMD increase in teriparatide-treated patients was 0.09 g/cm(2) across tertiles of baseline spine BMD. Compared with placebo, teriparatide significantly reduced the risk of new vertebral fracture for all endpoint BMD values. Teriparatide-mediated increases in spine BMD accounted for 30% (in the low baseline spine BMD tertile) to 41% (in the high baseline spine BMD tertile) of the reduction in vertebral fracture risk. CONCLUSIONS: Increases in BMD account for approximately one third of the vertebral fracture risk reduction seen with teriparatide. The majority of the risk reduction, however, results from improvements in non-BMD determinants of bone strength.

Aged↗

PubMed2006

Uses and misuses of quantitative ultrasonography in managing osteoporosis.

Quantitative ultrasonography is attractive as a test for osteoporosis, being precise, radiation-free, portable, and inexpensive, but it is still no substitute for the gold-standard test, dual-energy x-ray absorptiometry (DXA). At present, it cannot be used to diagnose osteoporosis or to monitor the effects of medications on bone density. As more data become available, however, it may play a larger role. A thorough understanding of the utility and limitations of this test is necessary for using it effectively in clinical practice.

Absorptiometry, Photon↗

PubMed2005

Safety and efficacy of risedronate in patients with age-related reduced renal function as estimated by the Cockcroft and Gault method: a pooled analysis of nine clinical trials.

UNLABELLED: The incidences of osteoporosis and renal insufficiency increase with age. We studied the influence of renal function on the safety and efficacy of risedronate 5 mg daily in osteoporotic women. Risedronate was safe and effective in osteoporotic women with mild, moderate, or severe age-related renal impairment. INTRODUCTION: The incidences of both osteoporosis and renal insufficiency increase with age; thus, the effect of renal impairment on the safety and efficacy of osteoporosis treatments is a clinical concern. Risedronate is a pyridinyl bisphosphonate well established as safe and effective in the treatment and prevention of osteoporosis. Currently, there is little available information about the effect of bisphosphonate treatment in patients with renal insufficiency. This retrospective analysis was conducted to study the influence of renal function on the safety and efficacy of risedronate in a population of osteoporotic women. MATERIALS AND METHODS: Combined data from nine randomized, double-blind, placebo-controlled phase III risedronate trials were analyzed. The patients in these studies had no markedly abnormal laboratory parameters that were considered clinically significant and no evidence of significant disease. This analysis included patients who received placebo (n = 4,500) or risedronate 5 mg (n = 4,496) for up to 3 years (average duration of exposure, 2 years) and who had renal impairment (creatinine clearance [CrCl] < 80 ml/min). CrCl was estimated by the Cockcroft and Gault method, based on age, weight, and serum creatinine. Patients were categorized as having mild (CrCl >or=50 to <80 ml/min), moderate (CrCl >or=30 to <50 ml/min), or severe (CrCl < 30 ml/min) renal impairment. RESULTS: Of the patients studied, renal impairment at baseline was mild in 48% (mean [range] serum creatinine, 0.9 [0.4-1.6] mg/dl), moderate in 45% (1.1 [0.6-1.9] mg/dl), and severe in 7% (1.3 [0.7-2.7] mg/dl). In both the placebo and risedronate treatment groups, the patients with the most severe renal impairment were older and had more severe osteoporosis. The incidences of overall adverse events and of renal function-related adverse events were similar in the placebo and risedronate 5 mg groups regardless of renal function. Furthermore, evaluation of changes from baseline in serum creatinine revealed no difference in renal function between the placebo and risedronate 5 mg groups in any of the renal impairment subgroups at any time-point. In all three subgroups, risedronate effectively preserved BMD and reduced the incidence of vertebral fractures. CONCLUSIONS: These findings show that risedronate is safe and effective in osteoporotic women with age-related mild, moderate, or severe renal impairment.

Age Factors↗

PubMed2005

Rationale, objectives and design of the Direct Analysis of Nonvertebral Fracture in the Community Experience (DANCE) study.

The experience in randomized placebo-controlled clinical trials may differ from that in community practice. The pivotal teriparatide [rhPTH(1-34)] studies were initiated when few therapeutic options for osteoporosis were available. The Direct Analysis of Non-Vertebral Fractures in Community Experience (DANCE) study is a prospective observational trial designed to examine the occurrence of nonvertebral fragility fractures in a large, diverse patient population treated with teriparatide. The occurrence of clinical vertebral fractures and back pain will also be examined, as will bone mineral density, bone mineral content, bone area, safety and tolerability. Subjects will be followed through a course of teriparatide therapy for up to 24 months and for an additional 24 months after cessation of treatment. Therefore, subjects may participate in this study for up to 48 months. DANCE will provide data on the effectiveness and tolerability of teriparatide therapy in clinical practice that will complement the results of published controlled clinical trials.

Bone Density↗

PubMed2005

A new concept for bisphosphonate therapy: a rationale for the development of monthly oral dosing of ibandronate.

Oral daily and weekly bisphosphonates represent the current mainstay of treatment for postmenopausal osteoporosis (PMO). However, the inconvenience of frequent dosing is known to negatively affect adherence to therapy in the long term. This has prompted the development of convenient oral bisphosphonate regimens that feature simple, less frequent dosing schedules. Such regimens require high potency agents, which can be given at low effective doses and that also have good tolerability. Ibandronate is a potent, nitrogen-containing bisphosphonate with proven efficacy when given intermittently to estrogen-depleted beagle dogs, rats and cynomolgus monkeys. Clinically, a pivotal prospective study has established that oral ibandronate has significant vertebral fracture efficacy in PMO, whether given daily (2.5 mg) or intermittently (20 mg every other day for 12 doses every 3 months; extended between-dose interval>2 months). Both oral regimens were well tolerated, which is noteworthy as patients with a history of gastrointestinal (GI) disturbance were not specifically excluded. As a result of these findings, a large, multinational, randomized, double-blind study (Monthly Oral iBandronate In LadiEs: MOBILE) is currently exploring the non-inferiority of once-monthly oral ibandronate (100 or 150 mg) to the oral daily ibandronate (2.5 mg) regimen with proven anti-fracture efficacy, in terms of lumbar spine bone mineral density (BMD) change. As with the trials investigating the weekly administration of other bisphosphonates, vertebral fracture efficacy will be inferred if the study demonstrates the non-inferiority of once-monthly ibandronate to the proven oral daily regimen in terms of spinal BMD change. The availability of this once-monthly ibandronate regimen is expected to offer benefits in terms of convenience (by having to follow dosing recommendations once a month vs. once daily or weekly) and potentially tolerability (by reducing the potential for upper GI irritation that can result from frequent, repeated exposure). Greater convenience and tolerability may enhance the therapy adherence and, hence, improve long-term therapeutic outcomes in PMO.

Administration, Oral↗

PubMed2005

Parathyroid hormone and teriparatide for the treatment of osteoporosis: a review of the evidence and suggested guidelines for its use.

All therapies currently recommended for the management of osteoporosis act mainly to inhibit bone resorption and reduce bone remodeling. PTH and its analog, teriparatide [recombinant human PTH(1-34)], represent a new class of anabolic therapies for the treatment of severe osteoporosis, having the potential to improve skeletal microarchitecture. Significant reductions in both vertebral and appendicular fracture rates have been demonstrated in the phase III trial of teriparatide, involving elderly women with at least one prevalent vertebral fracture before the onset of therapy. However, there is as yet no evidence that the antifracture efficacy of PTH will be superior to the bisphosphonates, whereas cost-utility estimates suggest that teriparatide is significantly more expensive. Teriparatide should be considered as treatment for postmenopausal women and men with severe osteoporosis, as well as for patients with established glucocorticoid-induced osteoporosis who require long-term steroid treatment. Teriparatide should also be considered for the management of individuals at particularly high risk for fractures, including subjects who are younger than age 65 and who have particularly low bone mineral density measurements (T scores < or = 3.5). Teriparatide therapy is not recommended for more than 2 yr, based, in part, on the induction of osteosarcoma in a rat model of carcinogenicity. Total daily calcium intake from both supplements and dietary sources should be limited to 1500 mg together with adequate vitamin D intake (< or =1000 U/d). Monitoring of serum calcium may be safely limited to measurement after 1 month of treatment; mild hypercalcemia may be treated by withdrawing dietary calcium supplements, reducing the dosing frequency of PTH, or both. At present, concurrent therapy with antiresorptive therapy, particularly bisphosphonates, should be avoided, although sequential therapy with such agents may consolidate the beneficial effects upon the skeleton after PTH is discontinued.

Aged↗

PubMed2005

Monthly oral ibandronate therapy in postmenopausal osteoporosis: 1-year results from the MOBILE study.

UNLABELLED: Once-monthly (50/50, 100, and 150 mg) and daily (2.5 mg; 3-year vertebral fracture risk reduction: 52%) oral ibandronate regimens were compared in 1609 women with postmenopausal osteoporosis. At least equivalent efficacy and similar safety and tolerability were shown after 1 year. INTRODUCTION: Suboptimal adherence to daily and weekly oral bisphosphonates can potentially compromise therapeutic outcomes in postmenopausal osteoporosis. Although yet to be prospectively shown in osteoporosis, evidence from randomized clinical trials in several other chronic conditions shows that reducing dosing frequency enhances therapeutic adherence. Ibandronate is a new and potent bisphosphonate with antifracture efficacy proven for daily administration and also intermittent administration with a dose-free interval of >2 months. This report presents comparative data on the efficacy and safety of monthly and daily oral ibandronate regimens. MATERIALS AND METHODS: MOBILE is a 2-year, randomized, double-blind, phase III, noninferiority trial. A total of 1609 women with postmenopausal osteoporosis were assigned to one of four oral ibandronate regimens: 2.5 mg daily, 50 mg/50 mg monthly (single doses, consecutive days), 100 mg monthly, or 150 mg monthly. RESULTS: After 1 year, lumbar spine BMD increased by 3.9%, 4.3%, 4.1%, and 4.9% in the 2.5, 50 /50, 100, and 150 mg arms, respectively. All monthly regimens were proven noninferior, and the 150 mg regimen superior, to the daily regimen. All monthly regimens produced similar hip BMD gains, which were larger than those with the daily regimen. All regimens similarly decreased serum levels of C-telopeptide, a biochemical marker of bone resorption. Compared with the daily regimen, a significantly larger proportion of women receiving the 100 and 150 mg monthly regimens achieved predefined threshold levels for percent change from baseline in lumbar spine (6%) or total hip BMD (3%). All regimens were similarly well tolerated. CONCLUSIONS: Monthly ibandronate is at least as effective and well tolerated as the currently approved daily ibandronate regimen in postmenopausal osteoporosis.

Absorptiometry, Photon↗

PubMed2005

Bone density and markers of bone turnover in predicting fracture risk and how changes in these measures predict fracture risk reduction.

Surrogate markers in clinical medicine provide a useful means to assess therapeutic response to pharmacologic therapy in a wide range of chronic disease states. In the area of osteoporosis, the surrogate markers of change in bone mineral density (BMD) and bone turnover markers (BTM) provide the clinician with a means of assessing the biologic response to osteoporosis-specific pharmacologic agents. Increases in BMD and/or reductions in BTM can independently be correlated to reductions in vertebral and nonvertebral fracture risk. In managing osteoporosis patients, the BTM change at an earlier point of time after initiation of therapy and a change in BTM can provide earlier feed-back to the patient and clinician regarding issues such as compliance and a bone biologic response. An increase in BMD at 12 or 24 months after initiation of therapy is also evidence of an improvement in bone strength though with antiresorptive agents no change in BMD may also be associated with risk reduction within clinical trial sets. In this regard, changes in BMD and BTM are complimentary in their application to patient management.

Biomarkers↗

PubMed2005

Treatment of osteoporosis in chronic kidney disease and end-stage renal disease.

As glomerular filtration rate (GFR) declines from age-related bone loss or disease that specifically induces a decline in GFR, there are a number of metabolic bone conditions that may accompany the decline in GFR. These metabolic bone conditions span a spectrum from mild-to-severe secondary hyperparathyroidism in early stages of chronic kidney disease (CKD) to the development of additional heterogeneous forms of bone diseases each with its distinctly quantitative bone histomorphometric characteristics. Osteoporosis can also develop in patients with CKD and ESRD for many reasons beyond age-related bone loss and postmenopausal bone loss. The diagnosis of osteoporosis in patients with severe CKD or end-stage renal disease (ESRD) is not as easy to do as it is in patients with postmenopausal osteoporosis (PMO)--neither fragility fractures nor The World Health Organization bone mineral density criteria can be used to diagnose osteoporosis in this population since all forms of renal bone disease may fracture or have low "T scores". The diagnosis of osteoporosis in patients with CKD/ESRD must be done by first the exclusion of the other forms of renal osteodystrophy, by biochemical profiling or by double tetracycline-labeled bone biopsy; and the finding of low trabecular bone volume. In such patients, preliminary data would suggest that oral bisphosphonates seem to be safe and effective down to GFR levels of 15 mL/min. In patients with stage 5 CKD who are fracturing because of osteoporosis or who are on chronic glucocorticoids, reducing the oral bisphosphonate dosage to half of its usual prescribed dosing for PMO seems reasonable from known bisphosphonate pharmacokinetics, though we do need better scientific data to fully understand bisphosphonate usage in this population.

Bone Density↗

PubMed2005

Treatment of metabolic bone disease in patients with chronic renal disease: a perspective for rheumatologists.

As glomerular filtration rate (GFR) declines from age-related bone loss or disease that specifically induces a decline in GFR, there are a number of metabolic bone conditions that may accompany the decline in GFR. These metabolic bone conditions span a spectrum from mild-to-severe secondary hyperparathyroidism in early stages of chronic kidney disease (CKD) to the development of additional heterogeneous forms of bone diseases each with distinctly quantitative bone histomorphometric characteristics. Osteoporosis can also develop in patients with CKD and end-stage renal disease (ESRD) for many reasons beyond age-related bone loss and postmenopausal (PMO) bone loss. Diagnosing osteoporosis in patients with severe CKD or ESRD is not as easy to do as it is in patients with PMO. The diagnosis of osteoporosis in patients with CKD/ESRD must be done by first excluding other forms of renal osteodystrophy, through biochemical profiling or by double tetracycline-labeled bone biopsy and the finding of low trabecular bone volume. In such patients oral bisphosphonates seem to be safe and effective down to GFR levels of 15 mL/min. In patients with stage 5 CKD, who are fracturing because of osteoporosis or who are on chronic glucocorticoids, reducing the oral bisphosphonate dosage to half of its usual prescribed dosing for PMO seems reasonable from known bisphosphonate pharmacokinetics. However, we need better scientific data to fully understand bisphosphonate usage in this population. This paper deals with the evidence available to understand management of patients with CKD and opinions on what might be a reasonable clinical approach where evidence is currently lacking.

Bone Diseases, Metabolic↗

PubMed2005

Optimizing the management of postmenopausal osteoporosis with bisphosphonates: the emerging role of intermittent therapy.

BACKGROUND: The utility of bisphosphonates in the treatment of postmenopausal osteoporosis is compromised by the requirement of frequent oral administration or complex cyclic regimens. Recognition that simplified dosing regimens and reduced frequency of administration are important factors for improving adherence to therapy has led to the development of bisphosphonates with less frequent dosing regimens that aim to offer greater convenience. OBJECTIVE: This paper reviews the available data concerning the efficacy and tolerability of intermittent (less frequent than weekly) bisphosphonate dosing regimens for the treatment of postmenopausal osteoporosis, with particular focus on the potential implications for clinical management. METHODS: Papers on intermittent or cyclic bisphosphonate dosing regimens were identified by searching MEDLINE using the following terms: dose, dosing, dosage, or drug therapy; intermittent, cyclic, cyclical, weekly, monthly, month, week, administration, regimen, or schedule; and etidronate, alendronate, risedronate, zoledronate, neridronate, pamidronate, clodronate, ibandronate, or tiludronate. RESULTS: Because the currently available bisphosphonates differ in chemical structure, potency, and other physicochemical and biologic characteristics, comparable dose-free intervals may not be appropriate for all drugs. Several bisphosphonates have demonstrated efficacy in terms of an increase in bone mineral density (BMD) and a decrease in markers of bone turnover when administered intermittently. However, evidence of fracture benefit from a less frequent bisphosphonate dosing regimen was demonstrated recently. The nitrogen-containing bisphosphonate ibandronate was associated with a significant decrease in vertebral fracture risk when administered as an intermittent dosing regimen (P < 0.001 vs placebo). This study supports the concept that bisphosphonates such as ibandronate can be effectively administered less frequently than daily or weekly. CONCLUSIONS: Bisphosphonate therapy using intermittent schedules with between-dose intervals longer than 1 week is capable of reducing the risk of fracture, improving BMD, and suppressing biochemical markers of bone turnover. Planned and ongoing trials will determine the place of intermittent bisphosphonates in the treatment algorithm for postmenopausal osteoporosis.

Administration, Oral↗