Treatment of postmenopausal osteoporosis

Osteoporosis: evaluation and treatment

Osteoporosis is a common and costly disease. This article discusses the pathophysiology, diagnosis, and treatment of osteoporosis, including hormone replacement, bisphosphonates, calcitonin, raloxifene, and alternative therapies. As our population ages, osteoporosis will become an even more common disease.

The role of selective estrogen receptor modulators in the prevention and treatment of osteoporosis

Osteoporosis can affect almost everyone in the population, and although clinical outcome of fracture is manifested in late life, the disease process begins in the early postmenopausal years in women. The pharmacologic agents currently available for osteoporosis prevention and treatment act by inhibiting bone resorption, and include estrogen or hormone replacement therapy (estrogen with progestin), bisphosphonates, salmon calcitonin nasal spray, and selective estrogen receptor modulators (SERMs). Raloxifene is a benzothiophene SERM that has estrogen against effects in bone and on serum lipid metabolism and estrogen antagonist effects on breast and uterine tissue. This article summarizes the effects of these antiresorptive agents, as measured by changes in bone mineral density, biochemical markers of bone turnover, and incident fractures in postmenopausal osteoporosis.

Treatment with 1,25-dihydroxyvitamin D3 reduces impairment of human osteoblast functions during cellular aging in culture

Adequate responses to various hormones, such as 1,25-dihydroxyvitamin D(3) (calcitriol) are a prerequisite for optimal osteoblast functions. We have previously characterized several human diploid osteoblastic cell lines that exhibit typical in vitro aging characteristics during long-term subculturing. In order to study in vitro age-related changes in osteoblast functions, we compared constitutive mRNA levels of osteoblast-specific genes in early-passage (< 50% lifespan completed) with those of late-passage cells (> 90% lifespan completed). We found a significant reduction in mRNA levels of alkaline phosphatase (AP: 68%), osteocalcin (OC: 67%), and collagen type I (ColI: 76%) in in vitro senescent late-passage cells compared to early-passage cells, suggesting an in vitro age-related impairment of osteoblast functions. We hypothesized that decreased osteoblast functions with in vitro aging is due to impaired responsiveness to calcitriol known to be important for the regulation of biological activities of the osteoblasts. Thus, we examined changes in vitamin D receptor (VDR) system and the osteoblastic responses to calcitriol treatment during in vitro osteoblast aging. We found no change in the amount of VDR at either steady state mRNA level or protein level with increasing in vitro osteoblast age and examination of VDR localization, nuclear translocation and DNA binding activity revealed no in vitro age-related changes. Furthermore, calcitriol (10(-8)M) treatment of early-passage osteoblastic cells inhibited their proliferation by 57 +/- 1% and stimulated steady state mRNA levels of AP (1.7 +/- 0.1-fold) and OC (1.8 +/- 0.2-fold). Similarly, calcitriol treatment increased mRNA levels of AP (1.7 +/- 0.2-fold) and OC (3.0 +/- 0.3-fold) in late-passage osteoblastic cells. Thus, in vitro senescent osteoblastic cells maintain their responsiveness to calcitriol and some of the observed in vitro age-related decreases in biological markers of osteoblast functions can be reverted by calcitriol treatment.

Role of estrogens in the management of postmenopausal bone loss

It is well known that estrogen deficiency is the major determinant of bone loss in postmenopausal women. Estrogen is important to the bone remodeling process through direct and indirect actions on bone cells. The largest clinical experience exists with estrogen therapy, demonstrating its successful prevention of osteoporosis as well as its positive influence on oral bone health, vasomotor and urogenital symptoms, and cardiovascular risk factors, which may not occur with other nonestrogen-based treatments. Compliance with HRT, however, is typically poor because of the potential side effects and possible increased risk of breast or endometrial cancer. Nevertheless, there is now evidence that lower doses of estrogens in elderly women may prevent bone loss while minimizing the side effects seen with higher doses of estrogen. Additionally, when adequate calcium, vitamin D, and exercise are used in combination with estrogen-based treatments, more positive increases occur in bone density. The benefits and risks of HRT must be assessed on a case-by-case basis, and the decision to use HRT is a matter for each patient in consultation with her physician. Estrogen-based therapy remains the treatment of choice for the prevention of osteoporosis in most postmenopausal women, and there may be a role for estrogen to play in the prevention of corticosteroid osteoporosis. Combination therapies using estrogen should probably be reserved for patients who continue to fracture on single therapy or should be used in patients who present initially with severe osteoporosis.

Osteoporosis therapies for rheumatoid arthritis patients: minimizing gastrointestinal side effects

OBJECTIVE

This manuscript identifies characteristics that put people with rheumatoid arthritis (RA) at high risk for osteoporosis or gastrointestinal (GI) disturbances. The manuscript then reviews therapies available for osteoporosis in the United States and makes recommendations about choosing therapies that minimize GI adverse effects in RA patients at high risk for such events.

DATA SOURCES

References identified through MEDLINE, abstracts, and prescribing information for individual drugs.

DATA EXTRACTION

Characteristics that predispose patients to osteoporosis and GI problems were identified. Data on individual osteoporosis therapies were assessed by risk-benefit analysis and appropriateness for use in patients at risk for GI disturbances.

DATA SYNTHESIS

High risk of osteoporosis in people with RA is caused by disease activity, medication effects, physical inactivity, and standard risk factors such as postmenopausal status and increased age. Patients with RA are frequently at high GI risk if they are receiving nonsteroidal anti-inflammatory drugs or corticosteroids. Because of the high potential for erosive esophagitis and other upper GI disorders with alendronate, caution is warranted in prescribing alendronate to RA patients with high GI risk. In such patients, estrogen replacement therapy, selective estrogen receptor modulators, or calcitonin should be considered for treatment, and either estrogen replacement therapy or selective estrogen receptor modulators should be considered for osteoporosis prevention.

CONCLUSIONS

Assessment of GI risk is important in patients with RA and osteoporosis. Risk factors should be considered when choosing osteoporosis therapies.

Quantitative ultrasound and bone mineral density are equally strongly associated with risk factors for osteoporosis

Because resources do not allow all women to be screened for osteoporosis, clinical risk factors are often used to identify those individuals at increased risk of fracture who are then assessed by bone densitometry. The aim of this study was to compare calcaneal quantitative ultrasound (QUS) and axial bone mineral density (BMD) T and Z scores in a large group of women, some with no clinical risk factors and others with one or more risk factors for osteoporosis. The study population consisted of 1115 pre- and postmenopausal women. A subgroup of 530 women was used to construct reference data for calculating T and Z scores. A total of 786 women was found to have one or more of the following risk factors: (i) atraumatic fracture since the age of 25 years, (ii) report of X-ray osteopenia, (iii) predisposing medical condition or use of therapy known to affect bone metabolism, (iv) premature menopause before the age of 45 years or a history of amenorrhea of longer than 6 months duration, (v) family history of osteoporosis, (vi) body mass index (BMI) <20 kg/m2, and (vii) current smoking habit. Calcaneal broadband ultrasound attenuation (BUA) and speed of sound (SOS) measurements were performed on a Hologic Sahara and a DTUone and BMD was measured at the spine and hip using dual-energy X-ray absorptiometry (DXA). The Z score decrements associated with the seven risk factors calculated using multivariate regression analysis were similar for QUS and BMD measurements. Z score decrements (mean of BMD and QUS measurements combined) associated with a history of atraumatic fracture (-0.67), X-ray osteopenia (-0.36), a family history of osteoporosis (-0.23), and a low BMI (-0.53) were all statistically significant compared with women with no risk factors. Z score decrements associated with a medical condition or use of therapy known to affect bone metabolism, a premature menopause or prolonged amenorrhea, or those who were current smokers were not significantly different from zero. As the number of risk factors present in each individual increased, the mean Z score decrements became more negative, increasing from -0.28 for women with one risk factor to -1.19 for those with four or more risk factors. QUS and BMD measurements yielded similar mean Z scores for women with one, two, three, or more than four risk factors. Using the World Health Organization (WHO) criteria to diagnose osteoporosis for BMD measurements and revised diagnostic criteria for QUS, approximately one-third of postmenopausal women aged 50+ years with clinical risk factors were classified as osteoporotic compared with only 12% of women without clinical risk factors. Over two-thirds of postmenopausal women with risk factors were classified as osteopenic or osteoporotic and approximately 28% were classified as normal. The proportion of women classified into each diagnostic category was similar for BMD and QUS. In conclusion, clinical risk factors for osteoporosis affected calcaneal BUA and SOS Z score measurements to the same extent as axial BMD Z score measurements. Provided revised diagnostic criteria are adopted for QUS, similar proportions of postmenopausal women are identified as osteopenic or osteoporotic as with BMD.

Bone densitometry and the diagnosis of osteoporosis

Over the past decade, bone density scanning has come to be seen as an essential part of the evaluation of patients at risk of osteoporosis. Although dual x-ray absorptiometry (DXA) is the technique most associated with the recent growth in bone densitometry, several innovative devices for performing measurements at sites in the peripheral skeleton are also available. This article examines the question of whether there is any one method or measurement site that performs better than all the others at identifying patients at risk of fracture. Given that it is essential to make greater use of the small, low-cost peripheral devices if the many millions of women most at risk are to be identified and treated, what approaches to the interpretation of bone density scans can be adopted to ensure the greatest degree of consistency among different methods? Finally, does it matter if the imperfect correlation among different types of measurement results in different patients being selected for treatment on the basis of different techniques?

Peripheral or central densitometry: does it matter which technique we use?

Over the past decade, bone density scans have assumed an essential role in the diagnosis of osteoporosis. Although dual X-ray absorptiometry (DXA) scans of the central skeleton remain widely used, a variety of different types of equipment for measuring peripheral sites is now available. However, the poor correlation between different types of measurement and a lack of consensus on how results from peripheral sites should be interpreted have proved a barrier to the more widespread use of these devices. These issues prompt the following questions: Which technique best identifies patients at risk of fracture? What approaches to scan interpretation ensure the closest agreement among different methods? Does it matter if different patients are selected for treatment on the basis of different techniques? The relative risk (RR)of fracture derived from prospective studies is a key parameter for comparing the clinical value of different techniques. Recent reports confirm the advantages of hip bone mineral density compared with peripheral measurements for predicting hip fracture risk, although for fractures at other sites the differences are inconclusive. Using receiver operating characteristic curves, we show that the guidelines adopted for scan interpretation are of crucial importance for ensuring that the information provided is used effectively. The closest agreement among different techniques is achieved by setting thresholds for peripheral devices that target either the same percentage of the population or the same percentage of future fracture cases as femur DXA. Different methods select different groups of individuals from the total pool of patients who will later sustain a fracture, with the most successful technique being the one with the largest RR value. The emphasis placed by many studies on validating new techniques by studying their correlation with DXA may lead to the clinical value of peripheral devices being underestimated when the key datum is the RR value inferred from prospective fracture studies.

A functional polymorphic variant in the interleukin-6 gene promoter associated with low bone resorption in postmenopausal women

OBJECTIVE

To examine functional interleukin-6 (IL-6) -174 G-->C allelic variants in relation to bone turnover and bone mineral density (BMD) in postmenopausal women.

METHODS

Four hundred thirty-four healthy women living in the community (mean +/- SD age 71.7 +/- 5.7 years) were genotyped for the IL-6 -174 G-->C polymorphism. Serum levels of C-telopeptide of type I collagen (CTx), a marker of bone resorption, and osteocalcin (OC), a marker of bone formation, were determined. BMD at the hip and forearm was measured by dual-energy x-ray absorptiometry.

RESULTS

CTx levels differed significantly (P = 0.006) among IL-6 genotypes (mean +/- SEM 0.275 +/- 0.02 ng/ml, 0.325 +/- 0.01 ng/ml, and 0.356 +/- 0.02 ng/ml in women with the CC genotype [n = 68], the GC genotype [n = 204], and the GG genotype [n = 162], respectively). Compared with the GG group, age-adjusted odds ratios for high bone resorption were 0.65 (95% confidence interval [95% CI] 0.41-1.0, P = 0.06) and 0.37 (95% CI 0.18-0.73, P = 0.0047) in GC and CC subjects, respectively. In contrast, OC levels did not differ by genotype. BMD at the hip and forearm was 1.5-5% higher in CC subjects compared with GG subjects (P not significant). When the cohort was divided according to the median age (70.5 years), BMD was significantly decreased in older compared with younger postmenopausal women with the GG and GC genotypes (-9.6% on average; P < 0.01), but not in those with the CC genotype (-5.1% on average; P not significant).

CONCLUSION

Compared with the GC and GG IL-6 -174 G-->C genotypes, the CC genotype is associated with lower bone resorption and lesser decrease in bone mass in older postmenopausal women. These results suggest that IL-6 -174 G-->C alleles may be significant determinants of the risk for osteoporosis in elderly subjects.

Risedronate

Risedronate is a novel orally administered pyridinyl bisphosphonate indicated for the prevention or treatment of postmenopausal and glucocorticoid-induced osteoporosis and Paget's disease. The drug reduces bone turnover and decreases resorption chiefly through osteoclastic effects, with no undesirable effects on cortical porosity or thickness or on cancellous bone volume. Four randomised, double-blind trials have been carried out in 4873 patients with postmenopausal osteoporosis. In 2 of these studies, the primary end-point of vertebral fracture incidence was reduced by risedronate 5mg once daily by up to 65 and 49% relative to placebo after 1 and 3 years, respectively. Across all 4 trials, risedronate improved lumbar spine, femoral neck and femoral trochanter bone mineral density (BMD) statistically significantly relative to placebo. The drug also prevented bone loss in a study in 383 women with recent menopause, and reduced the risk of hip fracture in elderly women with confirmed osteoporosis in a trial involving a total of 9331 patients. Risedronate 5 mg/day plus estrogen has been shown to be superior to estrogen alone in a 12-month double-blind study in 524 women with at least 1-year's history of menopause. Two randomised, double-blind and placebo-controlled 12-month studies in a total of 518 patients have shown risedronate 5 mg/day to prevent or reverse bone loss in patients receiving glucocorticoid therapy. Risedronate 30 mg/day was associated with statistically significant reductions in mean serum levels of alkaline phosphatase (ALP) in noncomparative studies in patients with Paget's disease. ALP normalisation rates ranged from 53.8 to 65% across two 84-day treatment cycles in 2 of these trials in 180 patients. In a randomised, double-blind study in 123 patients, risedronate 30 mg/day for 2 months evoked significantly greater serum ALP responses than etidronate 400 mg/day for 6 months. The overall tolerability profile of risedronate was similar to that of placebo in clinical studies, with no evidence of acute-phase reactions or mineralisation defects, or excess incidence of upper GI lesions, in patients receiving the drug.

CONCLUSIONS

Risedronate is an effective and well tolerated novel bisphosphonate that is suitable for first-line therapy in Paget's disease. The rapid and sustained reductions in vertebral fracture incidence and BMD changes seen in patients with postmenopausal and glucocorticoid-induced osteoporosis indicate the drug to be a valuable treatment option with first-line potential, particularly in patients for whom hormonal therapy is inappropriate. The effects of the drug on hip fracture incidence in elderly women with confirmed osteoporosis point to a particular role in older patients, or those with more advanced disease.

Quantitative studies of bone with the use of 18F-fluoride and 99mTc-methylene diphosphonate

This article discusses methods for quantifying bone turnover based on tracer kinetic studies of the short-lived radiopharmaceuticals 99mTc-MDP and 18F-fluoride. Measurements of skeletal clearance obtained by using these tracers reflect the combined effects of skeletal blood flow and osteoblastic activity. The pharmacokinetics of each tracer is described, together with some of the quantitative tests of skeletal function that have been described in the literature. The physiologic interpretation of quantitative measurements of bone obtained with the use of short half-life radionuclides is discussed, and the advantages and limitations of 99mTc-MDP and 18F-fluoride are compared and contrasted. Currently, 18F-fluoride dynamic positron emission tomography (PET) is the technique of choice for physiologically precise quantitative studies of bone. However, comparable data could probably be obtained by using 99mTc-MDP if methods for single photon emission computed tomography (SPECT) quantitation were improved.

Structural trends in the aging femoral neck and proximal shaft: analysis of the Third National Health and Nutrition Examination Survey dual-energy X-ray absorptiometry data

Hip scans of U.S. adults aged 20-99 years acquired in the Third National Health and Nutrition Examination Survey (NHANES III) using dual-energy X-ray absorptiometry (DXA) were analyzed with a structural analysis program. The program analyzes narrow (3 mm wide) regions at specific locations across the proximal femur to measure bone mineral density (BMD) as well as cross-sectional areas (CSAs), cross-sectional moments of inertia (CSMI), section moduli, subperiosteal widths, and estimated mean cortical thickness. Measurements are reported here on a non-Hispanic white subgroup of 2,719 men and 2,904 women for a cortical region across the proximal shaft 2 cm distal to the lesser trochanter and a mixed cortical/trabecular region across the narrowest point of the femoral neck. Apparent age trends in BMD and section modulus were studied for both regions by sex after correction for body weight. The BMD decline with age in the narrow neck was similar to that seen in the Hologic neck region; BMD in the shaft also declined, although at a slower rate. A different pattern was seen for section modulus; furthermore, this pattern depended on sex. Specifically, the section modulus at both the narrow neck and the shaft regions remains nearly constant until the fifth decade in females and then declined at a slower rate than BMD. In males, the narrow neck section modulus declined modestly until the fifth decade and then remained nearly constant whereas the shaft section modulus was static until the fifth decade and then increased steadily. The apparent mechanism for the discord between BMD and section modulus is a linear expansion in subperiosteal diameter in both sexes and in both regions, which tends to mechanically offset net loss of medullary bone mass. These results suggest that aging loss of bone mass in the hip does not necessarily mean reduced mechanical strength. Femoral neck section moduli in the elderly are on the average within 14% of young values in females and within 6% in males.

Nonpeptide alpha(v)beta(3) antagonists. 1. Transformation of a potent, integrin-selective alpha(IIb)beta(3) antagonist into a potent alpha(v)beta(3) antagonist

Modification of the potent fibrinogen receptor (alpha(IIb)beta(3)) antagonist 1 generated compounds with high affinity for the vitronectin receptor alpha(v)beta(3). Sequential modification of the basic N-terminus of 1 led to the identification of the 5,6,7, 8-tetrahydro[1,8]naphthyridine moiety (THN) as a lipophilic, moderately basic N-terminus that provides molecules with excellent potency and selectivity for the integrin receptor alpha(v)beta(3). The THN-containing analogue 5 is a potent inhibitor of bone resorption in vitro and in vivo. In addition, the identification of a novel, nonpeptide radioligand with high affinity to alpha(v)beta(3) is also reported.

Low-dose esterified estrogens (0.3 mg/day): long-term and short-term effects on menopausal symptoms and quality of life in postmenopausal women

OBJECTIVE

To study the impact of low-dose unopposed esterified estrogens on menopausal symptoms and quality of life.

METHODS

In a long-term, 2-year, randomized, double-blind, placebo-controlled study, 204 postmenopausal women were treated with esterified estrogens 0.3 mg daily or placebo. Menopausal symptoms were assessed with a modified Kupperman index at baseline, 3, 6 and thereafter every 6 months. In a second 12-week, open-label, short-term pilot study, 25 postmenopausal women with moderate to severe vasomotor symptoms were treated with esterified estrogens 0.3 mg daily for 12 weeks. Vasomotor symptoms and quality of life were assessed using the Greene scale and Quality of Life Menopause Scale (QUALMS).

RESULTS

In the long-term study, significant (p < 0.05) reductions in total symptom scores were observed at each time point with esterified estrogens compared with placebo. Somatic symptom scores (hot flushes, night sweats, vaginal dryness) decreased significantly (p < 0.01) in patients treated with esterified estrogens 0.3 mg compared to baseline and placebo. In the short-term, open-label pilot study, the incidence of vasomotor symptoms was significantly (p < 0.01) reduced with esterified estrogens 0.3 mg from week 4 until the study end. Significant (p < 0.05) improvements versus baseline were seen in the somatic and vasomotor/sleep domains and in the total quality-of-life score.

CONCLUSIONS

Esterified estrogens 0.3 mg given daily provide adequate menopausal symptom relief and improved quality of life in postmenopausal women.

Assessment of physician responses to abnormal results of bone densitometry studies

OBJECTIVE

To assess how physicians who have ordered bone densitometry studies respond to abnormal results.

METHODS

We conducted a retrospective review of cases from physicians affiliated with a community teaching hospital. The study sample consisted of 142 female patients with abnormal bone mineral density (BMD) who had been referred by 50 physicians (internists or gynecologists). A questionnaire was completed for each patient, providing data about further investigations, treatment interventions, and frequency of referral to a specialist in bone diseases.

RESULTS

Of the patients diagnosed with osteoporosis on the basis of BMD studies, 20.4% had no further investigations, and 27.8% underwent only mammography. Of all the patients with osteoporosis, 10.6% received no therapy (calcium and vitamin D excluded). The majority of all patients (71.8%) received a combination of calcium and vitamin D. The most common treatment modality was hormone replacement therapy. The second most common treatment strategy was bisphosphonates. The percentage of all referrals to specialists in metabolic bone diseases was low--11.3% in the patients of internists and 14.5% in the patients of gynecologists.

CONCLUSION

In this study, the information provided by bone densitometry did not affect management in a substantial percentage of patients. A considerable percentage of patients underwent no further investigations to rule out secondary causes of osteoporosis.

Postmenopausal osteoporosis. Strategies for preventing bone loss, avoiding fracture

Implementing osteoporosis prevention strategies through lifestyle modification and pharmacologic treatment reduces patient morbidity and mortality, as well as the cost to the healthcare system. All women should be advised about their risk factors and educated about options to reduce the risk. The primary care physician plays a crucial role in identifying women at risk who are most likely to benefit from intervention. Treatment decisions should be based on each woman's medical history and personal preferences. The optimal duration of treatment, especially with the newer agents, such as the SERMs and bisphosphonates, requires further investigation.

Prevention and treatment of osteoporosis in women with breast cancer

Women who have had breast cancer may be at higher risk for osteoporosis than other women. First, they are more likely to undergo early menopause, due to chemotherapy-induced ovarian failure or oopherectomy. In addition, chemotherapy may have a direct adverse effect on bone mineral density (BMD), and osteoclastic activity may increase from the breast cancer itself. While estrogen therapy is considered standard for the prevention and treatment of osteoporosis, use of estrogen in women with a history of breast cancer is usually contraindicated. The approach to osteoporosis in women with breast cancer is also affected by the use of tamoxifen in many, as this drug appears to have opposite effects on BMD in premenopausal and postmenopausal women. We have reviewed therapeutic alternatives for the prevention and treatment of osteoporosis, focusing on patients with a history of breast cancer. Alendronate and raloxifene are currently approved in the United States for the prevention of osteoporosis; alendronate, raloxifene, and calcitonin are approved for treatment. Alendronate has the greatest positive effect on BMD and reduces the incidence of vertebral and nonvertebral fractures. Raloxifene and calcitonin appear to reduce the incidence of vertebral fractures; their effects on the incidence of nonvertebral fractures are not yet proven. Although no published studies specifically address the use of these approved agents for osteoporosis in women with breast cancer, understanding their relative effects on BMD in postmenopausal women in general will facilitate therapy selection in this population. Postmenopausal women with a history of breast cancer should undergo bone mineral analysis. Normal results and absence of other risk factors ensure that calcium and vitamin D intake are adequate. If osteopenia or other risk factors are present, preventive therapy with alendronate or raloxifene should be considered. For osteoporosis, treatment with alendronate should be strongly considered. Raloxifene and calcitonin are alternatives when alendronate is contraindicated. Further studies are needed to evaluate the optimal timing of initial bone mineral analysis in premenopausal women after breast cancer diagnosis and to determine the value of preventive treatment in women scheduled to undergo chemotherapy.

Raloxifene: a review of its use in postmenopausal osteoporosis

Raloxifene is a selective estrogen receptor modulator that partially mimics the effects of estrogens in bone and the cardiovascular system, while functioning as an antiestrogen in endometrial and breast tissue. In randomised placebo-controlled studies involving postmenopausal women or patients with osteoporosis, raloxifene 60 to 150 mg/day was effective in increasing bone mineral density (BMD) over 12- to 36-month periods. At the 60 mg/day recommended dosage, increases of 1.6 to 3.4%, 0.9 to 2.3% and 1.0 to 1.6% were reported in lumbar spine, femoral neck and total hip, respectively, versus < or =0.5% with placebo. Raloxifene 60 or 120 mg/day decreased the risk of vertebral fractures over a 36-month period in postmenopausal patients with osteoporosis. Significant reductions in radiographic fracture risk versus placebo (30 and 50%) occurred regardless of whether patients had existing fractures at baseline. Although raloxifene did not affect the overall incidence of nonvertebral fractures, a reduction in the incidence of ankle fracture was reported in comparison with placebo. In postmenopausal women, raloxifene 60 mg/day significantly reduced serum levels of total and low density lipoprotein cholesterol from baseline, compared with placebo. High density lipoprotein cholesterol and triglyceride levels were unaffected. Raloxifene 60 or 120 mg/day reduced the risk of invasive breast cancer by 76% during a median of 40 months' follow-up in postmenopausal patients with osteoporosis and no history of breast cancer. A relative risk reduction of 90% was reported for estrogen-receptor positive invasive breast cancers; estrogen-receptor negative cancer risk was unaffected by raloxifene. Raloxifene was generally well tolerated in clinical trials at dosages up to 150 mg/day. Adverse events thought to be related to raloxifene treatment were hot flushes and leg cramps. Venous thromboembolism was the only serious adverse event thought to be related to raloxifene treatment and a relative risk of 3.1 compared with placebo treatment was reported in patients with osteoporosis. Vaginal bleeding occurred in < or =6.4% of raloxifene-treated women but was reported by 50 to 88% of those receiving estrogens or hormone replacement therapy (HRT). Raloxifene treatment was not associated with stimulatory effects on the endometrium.

CONCLUSIONS

Raloxifene significantly increases BMD in postmenopausal women and reduces vertebral fracture risk in patients with osteoporosis. In clinical trials, raloxifene was generally well tolerated compared with placebo and HRT, although its propensity to cause hot flushes precludes use in women with vasomotor symptoms. In particular, the lack of stimulatory effects on the endometrium and the reduction in invasive breast cancer incidence indicate raloxifene as an attractive alternative to HRT for the management of postmenopausal osteonorosis.

Modulation of bone remodeling by active vitamin D: its role in the treatment of osteoporosis

Active vitamin D drugs are used for the treatment of osteoporosis in a number of countries, including Japan. However, their use is controversial. Here, we briefly discuss two issues that are important for understanding the role of active vitamin D (rather than plain vitamin D) in the treatment of osteoporosis: (1) whether or not its skeletal effects are mediated solely through its effects on intestinal calcium absorption in calcium- and vitamin D-replete states, and (2) how it modulates the bone remodeling process.

The use of bone densitometry in clinical practice

Bone densitometry is an established method for the assessment of osteoporosis as, according to the definition of osteoporosis, an accurate determination of the level of bone mass is central to the diagnostic assessment of osteoporosis. The diversity of different bone densitometry techniques, however, needs to be acknowledged. The World Health Organization criteria of osteoporosis should not be used for peripheral measurements, and their application to subject groups other than white women is still controversial. A large variety of bone densitometry and quantitative ultrasound techniques can be used for fracture risk assessment. Their results should be interpreted in the context of other clinical examinations and can then be used in making treatment decisions. For monitoring purposes, the ratio of response rate and long-term precision error determines longitudinal sensitivity. For all of these applications, careful quality assurance procedures need to be implemented. If applied in a responsible fashion, bone densitometry represents a powerful approach that is indispensable for the assessment of osteoporosis.

Pamidronate treatment of severe osteogenesis imperfecta in children under 3 years of age

Severe osteogenesis imperfecta (OI) is a hereditary disorder characterized by increased bone fragility and progressive bone deformity. Cyclical pamidronate infusions improve clinical outcome in children older than 3 yr of age with severe OI. Because earlier treatment may have potential to prevent deformities and improve functional prognosis in young children, we studied nine severely affected OI patients under 2 yr of age (2.3-20.7 months at entry) for a period of 12 months. Pamidronate was administered i.v. in cycles of 3 consecutive days. Patients received four to eight cycles during the treatment period, with cumulative doses averaging 12.4 mg/kg. Clinical changes were evaluated regularly during treatment, and radiological changes were assessed after 6-12 months of treatment. The control group consisted of six age-matched, severely affected OI patients, who had not received pamidronate treatment. During treatment bone mineral density (BMD) increased between 86-227%. The deviation from normal, as indicated by the z-score, diminished from -6.5 +/- 2.1 to -3.0 +/- 2.1 (P < 0.001). In the control group the BMD z-score worsened significantly. Vertebral coronal area increased in all treated patients (11.4 +/- 3.4 to 14.9 +/- 1.8 cm2; P < 0.001), but decreased in the untreated group (P < 0.05). In the treated patients, fracture rate was lower than in control patients (2.6 +/- 2.5 vs. 6.3 +/- 1.6 fractures/year; P < 0.01). No adverse side-effects were noted, apart from the well known acute phase reaction during the first infusion cycle. Pamidronate treatment in severely affected OI patients under 3 yr of age is safe, increases BMD, and decreases fracture rate.

Alfacalcidol inhibits bone resorption and stimulates formation in an ovariectomized rat model of osteoporosis: distinct actions from estrogen

Although alfacalcidol has been widely used for the treatment of osteoporosis in certain countries, its mechanism of action in bone, especially in the vitamin D-replete state, remains unclear. Here we provide histomorphometric as well as biochemical evidence that alfacalcidol suppresses osteoclastic bone resorption in an ovariectomized rat model of osteoporosis. Furthermore, when compared with 17beta-estradiol, a representative antiresorptive drug, it is evident that alfacalcidol causes a dose-dependent suppression of bone resorption, and yet maintains or even stimulates bone formation, as reflected in increases in serum osteocalcin levels and bone formation rate at both trabecular and cortical sites. 17beta-Estradiol, which suppresses bone resorption to the same extent as alfacalcidol, causes a parallel reduction in the biochemical and histomorphometric markers of bone formation. As a final outcome, treatment with alfacalcidol increases bone mineral density and improves mechanical strength more effectively than 17beta-estradiol, with a more pronounced difference in cortical bone. We conclude that estrogens depress bone turnover primarily by suppressing bone resorption and, as a consequence, bone formation as well, whereas alfacalcidol "supercouples" these processes, in that it suppresses bone resorption while maintaining or stimulating bone formation.

[Estimate of osteoporosis fracture risk with ultrasound bone assessment]

BACKGROUND

Multiple studies suggest that ultrasound measurement of the bone can be a rapid, cheap, and radiation-free alternative to determine the fracture risk. In this paper the ultrasound measurement of the bone was performed among 288 postmenopausal women, and the influence of gynecologic history and factors related to lifestyle on the obtained values was examined.

PATIENTS AND METHODS

One hundred nineteen healthy postmenopausal women and 169 women with previous osteoporotic fractures were included in the study. Both weight and height were determined and a clinical questionnaire was administered to assess factors related to bone mineral density. The values of broadband ultrasound attenuation (BUA) and speed of sound (SOS) were obtained with a contact ultrasound analyzer.

RESULTS

Among women without fractures the mean BUA and SOS values (64.1 [14.9] and 1,601.1 [34.5], respectively) were significantly higher than mean BUA (48.8 [17.3]) and SOS (1,573 [57.8]) values among women with fractures (p < 0.001). Using the logistic regression analysis for predicting fracture risk, the model that suited best was that including BUA (OR = 0.668 [0.544-0.818]), age (OR = 1.102 [1.055-1.151]), age at postmenopause (OR = 0.794 [0.731-0.862]) and height (OR = 0.932 [0.883-0.983]). The area under the curve for this model was 0.871.

CONCLUSIONS

BUA and SOS values are lower among women with osteoporotic fractures. The fracture risk can be predicted by means of a model including the variables BUA, age, postmenopausal age, and height.

Prevalence of osteoporosis risk factors and treatment among women aged 50 years and older

We conducted a cross-sectional, retrospective review to evaluate screening, diagnosis, and treatment of 389 women aged 50 years or older at risk for osteoporosis in a large primary care practice. Records randomly selected from a computerized database were reviewed for drug history, age, height, weight, and osteoporosis-related diagnoses, symptoms, and risk factors. Among the 389 women, 255 (65.5%) were receiving bone-preserving treatment (247 estrogen replacement exclusively). Most (70.4%) were white, with an average age of 61 years, and an average of 3.3 risk factors for osteoporosis. Risk factors were postmenopausal status 94%, age 65 years or older 53%, hysterectomy 39%, cigarette smoking 33%, and physical inactivity 30%. By logistic regression, the only positive predictor of antiresorptive therapy was hysterectomy (adjusted odds ratio [AOR] 2.52, 95% confidence interval [CI] 1.54-4.14). Negative predictors were physical inactivity (AOR 0.44, 95% CI 0.25-0.71), rheumatoid arthritis (AOR 0.31, 95% CI 0.12-0.79), and age 65 years and older (AOR 0.54, 95% CI 0.34-0.86). Controlling for age, women with four or more risk factors were 62% less likely to be receiving antiresorptive treatment (AOR 0.38, 95% CI 0.23-0.64) than those with fewer risk factors.

American Society of Clinical Oncology guideline on the role of bisphosphonates in breast cancer. American Society of Clinical Oncology Bisphosphonates Expert Panel

PURPOSE

To determine clinical practice guidelines for the use of bisphosphonates in the prevention and treatment of bone metastases in breast cancer and their role relative to other therapies for this condition.

METHODS

An expert multidisciplinary panel reviewed pertinent information from the published literature and meeting abstracts through May 1999. Additional data collected as part of randomized trials and submitted to the United States Food and Drug Administration were also reviewed, and investigators were contacted for more recent information. Values for levels of evidence and grade of recommendation were assigned by expert reviewers and approved by the panel. Expert consensus was used if there were insufficient published data. The panel addressed which patients to treat and when in their course of disease, specific drug delivery issues, duration of therapy, management of bony metastases with other therapies, and the public policy implications. The guideline underwent external review by selected physicians, members of the American Society of Clinical Oncology (ASCO) Health Services Research Committee, and the ASCO Board of Directors.

RESULTS

Bisphosphonates have not had an impact on the most reliable cancer end point: overall survival. The benefits have been reductions in skeletal complications, ie, pathologic fractures, surgery for fracture or impending fracture, radiation, spinal cord compression, and hypercalcemia. Intravenous (IV) pamidronate 90 mg delivered over 1 to 2 hours every 3 to 4 weeks is recommended in patients with metastatic breast cancer who have imaging evidence of lytic destruction of bone and who are concurrently receiving systemic therapy with hormonal therapy or chemotherapy. For women with only an abnormal bone scan but without bony destruction by imaging studies or localized pain, there is insufficient evidence to suggest starting bisphosphonates. Starting bisphosphonates in patients without evidence of bony metastasis, even in the presence of other extraskeletal metastases, is not recommended. Studies of bisphosphonates in the adjuvant setting have yielded inconsistent results. Starting bisphosphonates in patients at any stage of their nonosseous disease, outside of clinical trials, despite a high risk for future bone metastasis, is currently not recommended. Oral bisphosphonates are one of several options which can be used for preservation of bone density in premenopausal patients with treatment-induced menopause. The panel suggests that, once initiated, IV bisphosphonates be continued until evidence of substantial decline in a patient's general performance status. The panel stresses that clinical judgment must guide what is a substantial decline. There is no evidence addressing the consequences of stopping bisphosphonates after one or more adverse skeletal events. Symptoms in the spine, pelvis, or femur require careful evaluation for spinal cord compression and pathologic fracture before bisphosphonate use and if symptoms recur, persist, or worsen during therapy. The panel recommends that current standards of care for cancer pain, analgesics and local radiation therapy, not be displaced by bisphosphonates. IV pamidronate is recommended in women with pain caused by osteolytic metastasis to relieve pain when used concurrently with systemic chemotherapy and/or hormonal therapy, since it was associated with a modest pain control benefit in controlled trials.

CONCLUSION

Bisphosphonates provide a meaningful supportive but not life-prolonging benefit to many patients with bone metastases from cancer. Further research is warranted to identify clinical predictors of when to start and stop therapy, to integrate their use with other treatments for bone metastases, to identify their role in the adjuvant setting in preventing bone metastases, and to better determine their cost-benefit consequences.

Dose-proportional pharmacokinetics of risedronate on single-dose oral administration to healthy volunteers

Risedronate is a pyridinyl bisphosphonate approved for the treatment of Paget's disease (US-FDA) and in development for the treatment and prevention of osteoporosis. This study examined risedronate pharmacokinetics and tolerability after oral administration using a randomized, double-blind, parallel-group design. Healthy male and female volunteers (n = 22-23 subjects per dose) received a single oral dose of 2.5, 5, or 30 mg risedronate. Serum and urine samples were collected for 72 and 672 hours, respectively, and risedronate concentrations were determined by ELISA. Safety was evaluated by monitoring adverse events, clinical laboratory measurements, vital signs, and electrocardiograms. Mean Cmax (0.41, 0.94, and 5.1 ng/mL for 2.5, 5, and 30 mg, respectively), AUC (1.8, 3.9, and 21 ng.h/mL for 2.5, 5, and 30 mg, respectively), and urinary excretion (22, 63, and 260 micrograms for 2.5, 5, and 30 mg, respectively) were dose proportional, and there were no significant differences in tmax or CLR among the three doses. All doses were well tolerated; no serious adverse events occurred, and all but one of the adverse events were mild or moderate in severity. There was no evidence of an acute phase reaction occurring after oral administration of risedronate.

Association of transforming growth factor beta1 genotype with therapeutic response to active vitamin D for postmenopausal osteoporosis

Transforming growth factor beta (TGF-beta) is an important regulator of bone metabolism, its effects being intertwined with those of estrogen and vitamin D. A T-->C polymorphism in exon 1 of the TGF-beta1 gene, which results in the substitution of proline for leucine, is associated with bone mineral density (BMD). However, it is not known whether this polymorphism affects the response to treatment with active vitamin D or to hormone replacement therapy (HRT) in individuals with osteoporosis. Changes in BMD at the lumbar spine (L2-L4 BMD) were compared among TGF-beta1 genotypes in 363 postmenopausal Japanese women who were divided into three groups: an untreated, control group (n = 130), an active vitamin D treatment group (n = 117), and an HRT group (n = 116). TGF-beta1 genotype was determined with an allele-specific polymerase chain reaction assay. In the control group, the rate of bone loss decreased according to the rank order of genotypes TT (homozygous for the T allele) > TC (heterozygous) > CC (homozygous for the C allele), with a significant difference detected between the CC and TT genotypes. The positive response of L2-L4 BMD to HRT increased according to the rank order of genotypes TT < TC < CC, although the differences among genotypes were not statistically significant. Individuals with the CC genotype responded to active vitamin D treatment with an annual increase in L2-L4 BMD of 1.6%, whereas those with the TT or TC genotypes similarly treated lost bone to a similar extent as did untreated subjects of the corresponding genotype. These results suggest that TGF-beta1 genotype is associated with both the rate of bone loss and the response to active vitamin D treatment.

Bone mineral density of the lumbar spine in patients with advanced rheumatoid arthritis. Influence of functional capacity and corticosteroid use

We investigated factors that are related to generalized osteoporosis in advanced rheumatoid arthritis (RA). In this cross-sectional study we measured trabecular bone mineral density (BMD), by quantitative computerized tomography (QCT), in the lumbar spine of 57 patients with RA, most of whom were premenopausal women. In our material, 27 out of 57 patients (47%) had BMD <-1 SD expressed as Z-score and five patients had suffered from fractures. Our study shows that a cumulative corticosteroid dose (r = -0.41, p<0.010) and functional impairment (r = -0.37, p<0.050) were negatively related to spinal BMD, while daily intake of calcium correlated positively on BMD (r = 0.37, p<0.010). Our results indicate that low BMD is common in patients with advanced RA and it is associated with long-term corticosteroid use. Thus, in clinical practice we have to consider the benefits and harms of corticosteroid treatment and preventive therapy to osteoporosis.

Monitoring skeletal response to treatment which site to measure in the femur?

In the past it was usual to interpret bone mineral density (BMD) scans of the femur using the femoral neck, trochanter, or Ward's triangle sites. Recently, a study by the International Committee for Standards in Bone Measurement recommended that the total hip should be the preferred site for the interpretation of femur BMD, and another study described a new central hip site that may offer improved precision. This article compares the longitudinal sensitivities of the different femur BMD sites for monitoring patient response to treatment. The study population was 152 postmenopausal women enrolled in a trial of a bisphosphonate therapy. Spine and hip BMD scans were performed at 0, 1, and 2 yr. The mean percentage change at 2 yr was calculated for six sites in the hip, and the spine was also included for comparison. Treatment effect was defined as the difference in the BMD change between the treated and placebo groups. Although the data analysis incorporated a term for a calibration change caused by a repair of the dual X-ray absorptiometry scanner, the effect of this event on the estimation of treatment effect was negligible. Longitudinal sensitivity was derived by dividing the treatment effect by the root mean square error (RMSE) of the statistical model. Results (and standard errors) normalized to the ratio of treatment effect: RMSE for femoral neck BMD were as follows: femoral neck: 1.00; trochanter: 1.33 (0.38); intertrochanteric: 0.84 (0.41); total hip: 1.20 (0.38); Ward's triangle: 1.03 (0.27); central hip: 1.09 (0.30); spine: 2.08 (0. 45). At none of the femur sites was the change in BMD large enough to allow monitoring of response to treatment in individual patients. However, for studies involving the follow-up of a group of subjects, the longitudinal sensitivities of the different femur sites were equal within the statistical errors of the study. In particular, total hip BMD appears to be as effective as femoral neck BMD for detecting response to treatment in the femur in the setting of a clinical trial or similar research study.

Bisphosphonates in osteoporosis: recent clinical experience

Bisphosphonates are potent inhibitors of bone resorption that have come to play a prominent role in the prevention and treatment of various forms of osteoporosis and other metabolic bone disorders. Therapy in women with osteoporosis and at high fracture risk substantially reduces the incidence of vertebral and non-vertebral fractures. In younger postmenopausal women, bisphosphonates are attractive alternatives to oestrogen to prevent bone loss and the subsequent development of osteoporosis. Bisphosphonates have recently become the treatment of choice to prevent and treat the skeletal consequences of chronic corticosteroid therapy. When administered appropriately, these drugs are very well tolerated and have an excellent safety profile. The challenges now to clinicians are to identify the patients for whom bisphosphonate therapy is indicated and to devise dosing and monitoring strategies to enhance the long-term adherence to therapy required to realise the full benefits of these treatments.

Alendronate and estrogen-progestin in the long-term prevention of bone loss: four-year results from the early postmenopausal intervention cohort study. A randomized, controlled trial

BACKGROUND

Up to 3 years of treatment with alendronate, 5 mg/d, prevents postmenopausal bone loss.

OBJECTIVE

To determine whether the effect of alendronate is sustained at 4 years of treatment and persists after treatment is discontinued.

DESIGN

Randomized, controlled trial.

SETTING

United States and Europe.

PARTICIPANTS

1609 postmenopausal women 45 to 59 years of age.

INTERVENTION

Participants were randomly assigned to receive oral alendronate, 5 mg/d or 2.5 mg/d; placebo; or open-label estrogen-progestin. Women in the alendronate groups received alendronate for the first 2 years of the study. Treatment was then continued without change or replaced with placebo for the last 2 years of the study.

MEASUREMENTS

Annual measurement of bone mineral density.

RESULTS

By year 4, the bone mineral density of participants in the placebo group had decreased by 1% to 6% (P < 0.001). Four years of treatment with 5 mg of alendronate per day increased bone mineral density at the spine (mean change [+/-SE], 3.8%+/-0.3%), hip (mean, 2.9%+/-0.2%), and total body (mean, 0.9%+/-0.2%) (P < 0.001 overall). By year 4, bone mineral density at most skeletal sites was greater in participants who switched from alendronate to placebo than in those who continuously received placebo. In years 3 and 4, bone loss in participants who switched from alendronate to placebo was similar to that seen during years 1 and 2 in those who continuously received placebo. Compared with 5 mg of alendronate per day, estrogen-medroxyprogesterone acetate produced similar increases in bone mineral density and estradiol-norethisterone acetate produced increases that were substantially greater.

CONCLUSIONS

Four years of treatment with alendronate or estrogen-progestin prevented postmenopausal bone loss. A residual effect was seen 2 years after alendronate therapy was stopped; however, continuous alendronate treatment was more effective in preventing postmenopausal bone loss than 2 years of alendronate followed by 2 years of placebo.

Bisphosphonates: from grandparents to grandchildren

Bisphosphonates are synthetic analogues of pyrophosphate that inhibit bone resorption by their action on osteoclasts. Bisphosphonates have been extensively used in the elderly with primary and secondary osteoporosis, Paget's disease, and hypercalcemia of malignancy. In recent years, bisphosphonates have been used to treat children acutely for resistant hypercalcemia and chronically for various metabolic bone diseases. The theoretical concerns of possible adverse effects of these drugs on the growing skeleton have not been proven to be true. In the present review, we have critically analyzed the available literature on bisphosphonate therapy in both adult and pediatric clinical trials. Although not yet approved by the FDA for use in children, bisphosphonates, from published experience, demonstrate benefit to the child with no serious adverse effects. Based on the literature analysis the review furnishes detailed recommendations and practical guidelines regarding the use of oral and intravenous bisphosphonates in children. Bisphosphonates might be the first agents to provide the pediatrician with an opportunity to treat mineral and bone disorders of childhood, which until recently did not have satisfactory therapy.

Alterations of the trabecular pattern of the jaws in patients with osteoporosis

OBJECTIVE

The purpose of this study was to determine whether the morphologic features of the trabecular bones of the maxilla and mandible differ between patients with osteoporosis and normal controls.

STUDY DESIGN

Periapical radiographs, obtained from dentists of 11 patients with osteoporosis and 12 control subjects, were digitized at 600 dpi. A custom computer program measured morphologic features of the trabecular architecture. The mean values for each feature were determined for the osteoporotic and control groups and compared by anatomic site.

RESULTS

Twenty-four morphologic features of the trabeculae and marrow regions were examined in each anatomical site. A principal components analysis summarized these predictors to four. The Hotelling T (2) test found that patients with osteoporosis had significantly altered morphologic pattern in the anterior maxilla (P =.019) and the posterior mandible (P =.013) in comparison with the controls. A classification tree analysis separated all subjects into 2 groups with 92% accuracy.

CONCLUSIONS

The data support the hypothesis that patients with osteoporosis have an altered trabecular pattern in the jaws in comparison with normal subjects.

Long-term medical complications after traumatic spinal cord injury: a regional model systems analysis

OBJECTIVE

To analyze the incidence, risk factors, and trends of long-term secondary medical complications in individuals with traumatic spinal cord injury.

DESIGN

Data were reviewed from the National SCI Statistical Center on annual evaluations performed at 1, 2, 5, 10, 15, and 20 years after injury on patients injured between 1973 and 1998.

SETTING

Multicenter Regional SCI Model Systems.

MAIN OUTCOME MEASURES

Secondary medical complications at annual follow-up years, including pneumonia/atelectasis, autonomic dysreflexia, deep venous thrombosis, pulmonary embolism, pressure ulcers, fractures, and renal calculi.

RESULTS

Pressure ulcers were the most frequent secondary medical complications in all years, and individuals at significant (p < .05) risk included those with complete injuries (years 1, 2, 5, 10), younger age (year 2), concomitant pneumonia/atelectasis (year 1, 2, 5), and violent injury (years 1, 2, 5, 10). The incidence of pneumonia/atelectasis was 3.4% between rehabilitation discharge and year-1 follow-up with those most significantly at risk being older than 60 years (years 1, 2, 5, 10) and tetraplegia-complete (years 1, 2). One-year incidence of deep venous thrombosis was 2.1% with a significant decline seen at year 2 (1.2%), and individuals most significantly (p < .001) at risk were those with complete injuries (year 1). The incidence of calculi (kidney and/or ureter) was 1.5% at 1-year follow-up and 1.9% at 5 years and was more frequent in patients with complete tetraplegia. Intermittent catheterization was the most common method of bladder management among patients with paraplegia but became less common at later postinjury visits.

CONCLUSIONS

Pressure ulcers, autonomic dysreflexia, and pneumonia/atelectasis were the most common long-term secondary medical complications found at annual follow-ups. Risk factors included complete injury, tetraplegia, older age, concomitant illness, and violent injury.

Prescribing hormone replacement therapy for menopausal symptoms

This paper addresses the clinical presentation of menopause, pretreatment assessment for hormone replacement therapy, benefits and risks of this treatment, common hormone replacement regimens and their side effects, and patient management. The case-based discussion focuses on the clinical management of a patient who is considering hormone replacement therapy for menopausal symptoms.

SERM Drugs for the Prevention of Osteoporosis

Although estrogens have proved useful in the prevention and treatment of osteoporosis, their side effects (for example, those on breast and endometrial cancer) are worrying to patients and physicians alike. Therefore, selective estrogen receptor modulator (SERM) drugs have been developed for use in their stead. The triphenylethylene drug tamoxifen proved to be protective against bone loss, but had side effects on uterus similar to those of natural estrogens. The tamoxifen derivative toremifene has less effect on bone. Further derivatives of tamoxifen (droloxifene, idoxifene) can be expected to act like tamoxifen when approved for clinical testing. The non-steroidal benzothiophene derivative, raloxifene, is the best SERM available thus far. It does not increase the incidence of endo-metrial cancer; in addition, like tamoxifen, it has the potential to prevent breast cancer, but has a better profile in its actions on bone (for example, it reduces the vertebral fracture rate more effectively than tamoxifen). Unlike estrogen, it decreases blood triglicerides as well as cholesterol.

The effect of various hormonal preparations and calcium supplementation on bone mass in early menopause. Is there a predictive value for the initial bone density and body weight?

OBJECTIVES

To compare the effect of various oestrogen and oestrogen/progestin preparations on bone density over a 2-year follow-up period in early postmenopausal women.

SETTING

A retrospective study on 315 women followed in a menopause clinic.

DESIGN

Antero-posterior lumbar spine bone densitometry was performed at baseline and between 18 and 24 months (mean 22 months) after initiation of hormone therapy. Participants were divided into six groups: women taking conjugated equine oestrogen (CEE) (n = 30); CEE plus sequential monthly medroxyprogesterone acetate (MPA) (n = 52); CEE plus sequential bimonthly MPA (n = 51); oral estradiol plus sequential monthly norethisterone acetate (n = 52); transdermal estradiol plus sequential monthly MPA (n = 30). A control group (n = 100) was composed of nonusers of hormones.

RESULTS

Hormone users, as a whole (n = 215), increased their bone mineral density (BMD) by 2.9% (4.8) as compared to the controls who lost 3.5% (3.4; P < 0. 001). There were similar gains in BMD amongst the five study groups. Calcium supplementation was associated with better results in all women: users of hormones and calcium had a gain in BMD of 4.5% (4.8) compared to only 1.5% (4.5) in those on hormones but without calcium (P < 0.001); amongst the controls, women using calcium lost 1.4% (2. 4), whilst nonusers of calcium lost 3.7% (2.4; P < 0.001). A dose-response curve was found between basal BMD and the effect of hormone therapy: women with osteoporosis (T-score <75%) demonstrated the largest increase in BMD - 6.3% (4.6), osteopenia (T-score 75-85%) was associated with a gain of 3.2% (5.6), low-borderline values (T-score 86-100%) gave a modest increase of 1.3% (4.3), and those with more than average BMD values (T-score >100%) actually lost bone despite hormone treatment [-2.1% (4.1)].

CONCLUSIONS

All hormone regimens had a similar bone conserving effect. Basal BMD value may serve as a predictor for the success of treatment. Calcium supplementation should be recommended in all postmenopausal women.

Effect of local density changes on the failure load of the proximal femur

Hip fracture among the elderly is a large and growing public health issue. Presently, all therapies approved for treatment and prevention of osteoporosis involve pharmacological agents that act systemically. In this study, we evaluated the feasibility of preventing osteoporotic hip fractures with local, rather than systemic, therapy. Our hypothesis is that local therapy to increase bone density may be as effective as systemic therapy in reducing fracture risk. Thus, the goal of this investigation was to use finite element analyses to study the effect of a localized increase in bone density on the strength of an osteopenic, human femur. Finite element predictions of the failure load were made after increasing the bone density within small regions in the proximal femur. The outcome variable from these analyses was the predicted load required to break a femur in a simulated fall to the side with impact on the greater trochanter. Increasing the density by 25% relative to baseline values in a small region (0.86 cm3) of the femoral neck increased the predicted failure load by 6.2%. The same density increase in a much larger region (4.92 cm3) increased the failure load by 15%. Inclusion of more than one region of increased density provided little additional benefit. In comparison, when the density of the entire femur was increased by 5% relative to baseline values, the predicted failure load increased by 5.4%. These findings suggest that agents capable of inducing increased bone density in small regions of the proximal femur have the potential to reduce the risk of hip fracture.

Evidence of continuing bone recovery at a mean of 7 years after liver transplantation

Patients with end-stage liver disease have low bone-turnover osteoporosis, and there is often further bone loss of 20% to 30% after orthotopic liver transplantation (OLT). Bone recovery after OLT has been reported, but data are limited. We undertook studies to determine whether bone recovery continues in the long term. Twenty-eight adult patients alive at least 5 years after OLT were studied (14 men, 14 women). Bone mineral density (BMD), serum parathyroid hormone (PTH), osteocalcin, and vitamin D levels were measured pretransplantation, at 3 months, 12 months, a mean of 46 months, and a mean of 85 months (range, 63 to 117 months) after transplantation. When BMD is expressed as a z score, the results were as follows: x0.82 +/- 0.22 pre-OLT; -2.04 +/- 0.27 at 3 months; -1.68 +/- 0.24 at 12 months; -1.23 +/- 0.24 at a mean of 46 months; and -1.0 +/- 0.26 at a mean of 85 months after OLT. The results at 46 and 85 months were significantly greater than the measurement at 3 months after OLT (P <.05). Furthermore, mean BMD (expressed as a z score) returns to the pre-OLT level at a mean of 85 months. At final follow-up, 9 of 28 patients had elevated PTH levels, and 14 of 27 patients had elevated osteocalcin levels. Five patients had spontaneous fractures in the first 12 months after transplantation, and 5 more patients had fractures by final follow-up. Even at 7 years after OLT, there was a significant increase in BMD (expressed as a z score) compared with 3 months after transplantation. Elevation of serum PTH and osteocalcin levels in some patients suggests continuing bone remodeling.