Prevention of early postmenopausal bone loss: controlled 2-year study in 315 normal females

Age-related mechanical strength evolution of trabecular bone under fatigue damage for both genders: Fracture risk evaluation

Bone tissue is a living composite material, providing mechanical and homeostatic functions, and able to constantly adapt its microstructure to changes in long term loading. This adaptation is conducted by a physiological process, known as "bone remodeling". This latter is manifested by interactions between osteoclasts and osteoblasts, and can be influenced by many local factors, via effects on bone cell differentiation and proliferation. In the current work, age and gender effects on damage rate evolution, throughout life, have been investigated using a mechanobiological finite element modeling. To achieve the aim, a mathematical model has been developed, coupling both cell activities and mechanical behavior of trabecular bone, under cyclic loadings. A series of computational simulations (ABAQUS/UMAT) has been performed on a 3D human proximal femur, allowing to investigate the effects of mechanical and biological parameters on mechanical strength of trabecular bone, in order to evaluate the fracture risk resulting from fatigue damage. The obtained results revealed that mechanical stimulus amplitude affects bone resorption and formation rates, and indicated that age and gender are major factors in bone response to the applied loadings.

Treatment with Standard and Low Dose of Conjugated Equine Estrogen Differentially Modulates Estrogen Receptor Expression and Response to Angiotensin II in Mesenteric Venular Bed of Surgically Postmenopausal Hypertensive Rats

Standard hormone therapy for menopausal women [conjugated equine estrogen (CEE) 0.625 mg] has been associated with increased risk of venous thrombosis. Regimens containing a lower CEE dose (0.30 mg) have been used clinically to decrease side effects of supraphysiologic doses of estrogen. In this study, we determined the effects of standard (SD) and low dose (LD) of CEE on venular function in ovariectomized (OVX) spontaneously hypertensive rats (SHR). Contractions by angiotensin-II (Ang-II 10 μM) in perfused mesenteric venular bed were markedly increased in OVX (21.5 ± 1.3 mmHg) compared with Sham (14.7 ± 1.1 mm Hg, P < 0.05). CEE-SD did not modify Ang-II responses in OVX, whereas CEE-LD restored Ang-II contraction to Sham levels. Endothelial nitric oxide synthase (eNOS) inhibition by L-NAME increased Ang-II contractions in Sham and CEE-LD and was without effect in venules of OVX SHR and CEE-SD. In OVX there was decreased NO generation in association with diminished eNOS phosphorylation and increased O2- generation in the venular wall. CEE-LD reverted the deleterious effects of ovariectomy. Although CEE-SD augmented eNOS phosphorylation in OVX, it was unable to increase NO levels, probably owing to its inability to reduce O2- Distinct effects by CEE-SD and CEE-LD parallel the differential modulation of Ang-II and estrogen receptors. Compared with Sham, CEE-LD increases Ang II receptor type 2, whereas CEE-SD modified ERβ expression in the venous bed. Interestingly, both CEE doses increased G protein-coupled estrogen receptor in OVX. Our data suggest that estrogen dose is an important factor for venous function. Although CEE-LD reversed deleterious effects of OVX, CEE-SD showed null effects despite its ability to increase eNOS activity.

Effect of Macroanatomic Bone Type and Estrogen Loss on Osteocyte Lacunar Properties in Healthy Adult Women

This is the first study to examine clinical human bone specimens by three-dimensional imaging to characterize osteocyte lacunar properties as a function of macroanatomic bone type and estrogen loss. We applied laboratory-based instrumentation [3D X-ray microscope (3DXRM), MicroXCT-200; Carl Zeiss/Xradia, Inc.] that reaches the same resolution as synchrotron microscopy. We used serial transiliac bone biopsy specimens to examine the effect of macroanatomic bone type and estrogen status on osteocyte lacunar properties. These properties include lacunar size (volume, axes lengths of the ellipsoidal lacunar voids), distribution (density, average near-neighbor lacunar distance), and shape factors (sphericity ratio, average eigenvalues, degree of equancy, elongation, and flatness) in both cortical and trabecular bone tissue. The lacunar properties (volume, surface area, density, near-neighbor distance, etc.) and the shape factors (E1, L1, L2, degree of equancy, degree of elongation) were different between cortical and trabecular bone regardless of estrogen status. In cortical bone and trabecular nodes, the lacunar void volume and surface area were either smaller or tended to be smaller in postmenopausal as compared to premenopausal women. The void volume-to-bone volume ratio of cortical bone showed declining trends with estrogen loss. While there were differences between trabecular and cortical bone tissue, the lacunar void sphericity ratio for trabecular struts shows decreasing trends in postmenopausal women. These data suggest that using 3DXRM can provide new insight into osteocyte lacunar properties in transiliac bone biopsies from patients with various skeletal disease/conditions and pharmaceutical treatments.

Effects of vitamin D supplements on bone mineral density: a systematic review and meta-analysis

BACKGROUND

Findings from recent meta-analyses of vitamin D supplementation without co-administration of calcium have not shown fracture prevention, possibly because of insufficient power or inappropriate doses, or because the intervention was not targeted to deficient populations. Despite these data, almost half of older adults (older than 50 years) continue to use these supplements. Bone mineral density can be used to detect biologically significant effects in much smaller cohorts. We investigated whether vitamin D supplementation affects bone mineral density.

METHODS

We searched Web of Science, Embase, and the Cochrane Database, from inception to July 8, 2012, for trials assessing the effects of vitamin D (D3 or D2, but not vitamin D metabolites) on bone mineral density. We included all randomised trials comparing interventions that differed only in vitamin D content, and which included adults (average age >20 years) without other metabolic bone diseases. We pooled data with a random effects meta-analysis with weighted mean differences and 95% CIs reported. To assess heterogeneity in results of individual studies, we used Cochran's Q statistic and the I(2) statistic. The primary endpoint was the percentage change in bone mineral density from baseline.

FINDINGS

Of 3930 citations identified by the search strategy, 23 studies (mean duration 23·5 months, comprising 4082 participants, 92% women, average age 59 years) met the inclusion criteria. 19 studies had mainly white populations. Mean baseline serum 25-hydroxyvitamin D concentration was less than 50 nmol/L in eight studies (n=1791). In ten studies (n=2294), individuals were given vitamin D doses less than 800 IU per day. Bone mineral density was measured at one to five sites (lumbar spine, femoral neck, total hip, trochanter, total body, or forearm) in each study, so 70 tests of statistical significance were done across the studies. There were six findings of significant benefit, two of significant detriment, and the rest were non-significant. Only one study showed benefit at more than one site. Results of our meta-analysis showed a small benefit at the femoral neck (weighted mean difference 0·8%, 95% CI 0·2-1·4) with heterogeneity among trials (I(2)=67%, p<0·00027). No effect at any other site was reported, including the total hip. We recorded a bias toward positive results at the femoral neck and total hip.

INTERPRETATION

Continuing widespread use of vitamin D for osteoporosis prevention in community-dwelling adults without specific risk factors for vitamin D deficiency seems to be inappropriate.

FUNDING

Health Research Council of New Zealand.

Vitamin D supplementation for prevention of mortality in adults

BACKGROUND

Available evidence on the effects of vitamin D on mortality has been inconclusive. In a recent systematic review, we found evidence that vitamin D3 may decrease mortality in mostly elderly women. The present systematic review updates and reassesses the benefits and harms of vitamin D supplementation used in primary and secondary prophylaxis of mortality.

OBJECTIVES

To assess the beneficial and harmful effects of vitamin D supplementation for prevention of mortality in healthy adults and adults in a stable phase of disease.

SEARCH METHODS

We searched The Cochrane Library, MEDLINE, EMBASE, LILACS, the Science Citation Index-Expanded and Conference Proceedings Citation Index-Science (all up to February 2012). We checked references of included trials and pharmaceutical companies for unidentified relevant trials.

SELECTION CRITERIA

Randomised trials that compared any type of vitamin D in any dose with any duration and route of administration versus placebo or no intervention in adult participants. Participants could have been recruited from the general population or from patients diagnosed with a disease in a stable phase. Vitamin D could have been administered as supplemental vitamin D (vitamin D3 (cholecalciferol) or vitamin D2 (ergocalciferol)) or as an active form of vitamin D (1α-hydroxyvitamin D (alfacalcidol) or 1,25-dihydroxyvitamin D (calcitriol)).

DATA COLLECTION AND ANALYSIS

Six review authors extracted data independently. Random-effects and fixed-effect meta-analyses were conducted. For dichotomous outcomes, we calculated the risk ratios (RRs). To account for trials with zero events, we performed meta-analyses of dichotomous data using risk differences (RDs) and empirical continuity corrections. We used published data and data obtained by contacting trial authors.To minimise the risk of systematic error, we assessed the risk of bias of the included trials. Trial sequential analyses controlled the risk of random errors possibly caused by cumulative meta-analyses.

MAIN RESULTS

We identified 159 randomised clinical trials. Ninety-four trials reported no mortality, and nine trials reported mortality but did not report in which intervention group the mortality occurred. Accordingly, 56 randomised trials with 95,286 participants provided usable data on mortality. The age of participants ranged from 18 to 107 years. Most trials included women older than 70 years. The mean proportion of women was 77%. Forty-eight of the trials randomly assigned 94,491 healthy participants. Of these, four trials included healthy volunteers, nine trials included postmenopausal women and 35 trials included older people living on their own or in institutional care. The remaining eight trials randomly assigned 795 participants with neurological, cardiovascular, respiratory or rheumatoid diseases. Vitamin D was administered for a weighted mean of 4.4 years. More than half of the trials had a low risk of bias. All trials were conducted in high-income countries. Forty-five trials (80%) reported the baseline vitamin D status of participants based on serum 25-hydroxyvitamin D levels. Participants in 19 trials had vitamin D adequacy (at or above 20 ng/mL). Participants in the remaining 26 trials had vitamin D insufficiency (less than 20 ng/mL).Vitamin D decreased mortality in all 56 trials analysed together (5,920/47,472 (12.5%) vs 6,077/47,814 (12.7%); RR 0.97 (95% confidence interval (CI) 0.94 to 0.99); P = 0.02; I(2) = 0%). More than 8% of participants dropped out. 'Worst-best case' and 'best-worst case' scenario analyses demonstrated that vitamin D could be associated with a dramatic increase or decrease in mortality. When different forms of vitamin D were assessed in separate analyses, only vitamin D3 decreased mortality (4,153/37,817 (11.0%) vs 4,340/38,110 (11.4%); RR 0.94 (95% CI 0.91 to 0.98); P = 0.002; I(2) = 0%; 75,927 participants; 38 trials). Vitamin D2, alfacalcidol and calcitriol did not significantly affect mortality. A subgroup analysis of trials at high risk of bias suggested that vitamin D2 may even increase mortality, but this finding could be due to random errors. Trial sequential analysis supported our finding regarding vitamin D3, with the cumulative Z-score breaking the trial sequential monitoring boundary for benefit, corresponding to 150 people treated over five years to prevent one additional death. We did not observe any statistically significant differences in the effect of vitamin D on mortality in subgroup analyses of trials at low risk of bias compared with trials at high risk of bias; of trials using placebo compared with trials using no intervention in the control group; of trials with no risk of industry bias compared with trials with risk of industry bias; of trials assessing primary prevention compared with trials assessing secondary prevention; of trials including participants with vitamin D level below 20 ng/mL at entry compared with trials including participants with vitamin D levels equal to or greater than 20 ng/mL at entry; of trials including ambulatory participants compared with trials including institutionalised participants; of trials using concomitant calcium supplementation compared with trials without calcium; of trials using a dose below 800 IU per day compared with trials using doses above 800 IU per day; and of trials including only women compared with trials including both sexes or only men. Vitamin D3 statistically significantly decreased cancer mortality (RR 0.88 (95% CI 0.78 to 0.98); P = 0.02; I(2) = 0%; 44,492 participants; 4 trials). Vitamin D3 combined with calcium increased the risk of nephrolithiasis (RR 1.17 (95% CI 1.02 to 1.34); P = 0.02; I(2) = 0%; 42,876 participants; 4 trials). Alfacalcidol and calcitriol increased the risk of hypercalcaemia (RR 3.18 (95% CI 1.17 to 8.68); P = 0.02; I(2) = 17%; 710 participants; 3 trials).

AUTHORS' CONCLUSIONS

Vitamin D3 seemed to decrease mortality in elderly people living independently or in institutional care. Vitamin D2, alfacalcidol and calcitriol had no statistically significant beneficial effects on mortality. Vitamin D3 combined with calcium increased nephrolithiasis. Both alfacalcidol and calcitriol increased hypercalcaemia. Because of risks of attrition bias originating from substantial dropout of participants and of outcome reporting bias due to a number of trials not reporting on mortality, as well as a number of other weaknesses in our evidence, further placebo-controlled randomised trials seem warranted.

Association of hypertension and bone mineral density in an elderly African American female population

BACKGROUND

Recent studies have shown that hypertension is inversely correlated with bone mineral density (BMD) as determined by dual energy x-ray absorptiometery (DXA) in different ethnic groups. But in most published studies, either the sample size was small or the study was limited by different measurement methods. These limitations leave this association controversial and inconclusive. The current study utilizes a sample of African American females referred for clinical screening of osteoporosis in our center to find out if any association of high blood pressure and BMD in this ethnic group exists. The secondary endpoint was to determine the effect of thiazide diuretics on BMD of the elderly African American females because, theoretically, thiazides are considered to have a positive impact on BMD.

METHODS

In this retrospective, cross-sectional study, 10 years of data were reviewed from 1113 medical records of African American females aged 65 years and older whose BMD values were measured by DXA at the lumbar spine (L1-L4) and both femoral necks (the standard sites for BMD determination) along with their T scores and Z scores (used to determine osteopenia vs osteoporosis). Our exclusion criteria included patients who: (1) were current smokers, (2) had a previous oophorectomy, (3) had a history of corticosteroid use, (4) had a history of biphosphonate use, (5) were on hormone replacement therapy, and (6) were diabetic and taking either pioglitazones or roziglitazones. A total of 148 patients were excluded from the analysis due to either incomplete data or exclusion criteria. The remaining sample was then divided into 2 groups based on their hypertensive status. For the subanalysis, the hypertensive group was further divided into 2 additional groups based on their thiazide usage.

RESULTS

We had complete data on 965 participants, of which 631 (65.3%) had a history of hypertension and 334 (34.7%) did not. Out of 631 hypertensive patients, 173 were found to be using thiazide diuretics as antihypertensive medication, while 458 were without thiazide diurectic use. The proportion of patients with both osteopenia and osteoporosis was similar in those with and without hypertension (50% vs 50%, p = .95 for osteopenia; 18% vs 19%, p = .95 for osteoporosis). There was no significant difference between the BMD at the lumbar spine, and right and left femoral necks between patients with and without hypertension. This lack of association held true when comparing the mean T scores and Z scores at the above sites. Within patients with a history of hypertension, there were no significant differences in the BMD, T score or Z score at any site with and without a history of thiazide diuretic use.

CONCLUSION

Hypertension in elderly African American females aged at least 65 years was not found to be correlated with low BMD at either the lumbar spine (L1-L4) or both femoral necks when confounding factors were taken into consideration. Mean BMD of the hypertensive cohort taking thiazide diuretics was found lower at the lumbar spine as compared to the hypertensive patients not taking thiazide diuretics.

Safety, Efficacy and Patient Acceptability of Bazedoxifene Acetate in the Management of Postmenopausal Osteoporosis

Many pharmacological agents are available for treatment of postmenopausal osteoporosis, including estrogen and the selective modulators of estrogen receptor (SERMS). Bazedoxifene is a third-generation SERM, which acts as estrogen agonist in bone and lipid metabolism and as an antagonist in the breast and endometrium. Studies demonstrated that bazedoxifene reduced significantly the risk of vertebral fractures. In a subgroup of patients at high risk (post-hoc analysis), a reduction of nonvertebral fractures risk was reported. Moreover, the combination of conjugated estrogens with bazedoxifene seems to offer an alternative to classical hormone therapy, improving the vasomotor symptoms and vaginal atrophy, without the use of a progestin. Bazedoxifene is a promising drug for the treatment and prevention of osteoporosis in postmenopausal women; however a safety concern regarding venous thromboembolic events is needed before starting treatment.

Vitamin D and cardiovascular outcomes: a systematic review and meta-analysis

CONTEXT

Several studies found association between vitamin D levels and hypertension, coronary artery calcification, and heart disease.

OBJECTIVE

The aim of this study was to summarize the evidence on the effect of vitamin D on cardiovascular outcomes.

DESIGN AND METHODS

We searched electronic databases from inception through August 2010 for randomized trials. Reviewers working in duplicate and independently extracted study characteristics, quality, and the outcomes of interest. Random-effects meta-analysis was used to pool the relative risks (RR) and the weighted mean differences across trials.

RESULTS

We found 51 eligible trials with moderate quality. Vitamin D was associated with nonsignificant effects on the patient-important outcomes of death [RR, 0.96; 95% confidence interval (CI), 0.93, 1.00; P = 0.08], myocardial infarction (RR, 1.02; 95% CI, 0.93, 1.13; P = 0.64), and stroke (RR, 1.05; 95% CI, 0.88, 1.25; P = 0.59). These analyses were associated with minimal heterogeneity. There were no significant changes in the surrogate outcomes of lipid fractions, glucose, or diastolic or systolic blood pressure. The latter analyses were associated with significant heterogeneity, and the pooled estimates were trivial in absolute terms.

CONCLUSIONS

Trial data available to date are unable to demonstrate a statistically significant reduction in mortality and cardiovascular risk associated with vitamin D. The quality of the available evidence is low to moderate at best.

Captopril improves osteopenia in ovariectomized rats and promotes bone formation in osteoblasts

The present study was designed to investigate the effects of captopril, an angiotensin-converting enzyme inhibitor (ACEI), on bone loss in aged ovariectomized (OVX) rats and its impact on the differentiation of cultured primary osteoblasts. Ten-month-old female Sprague-Dawley rats were used for the study. After 2 months post ovariectomy (OVX), the rats were treated with captopril (1 or 5 mg/kg/day, respectively) for another 2 months. At endpoint, trabecular bone of the fourth lumbar vertebrae (L4) was undecalcified and examined by bone histomorphometry; the fifth lumbar vertebrae (L5) were examined by compression test. Primary osteoblasts were isolated from the calvaria of newborn rats and treated with different concentrations of captopril in a different durations. The content of secreted alkaline phosphatase (ALP) and mRNA expression of collagen I in osteoblasts were determined to demonstrate osteoblast bone formation. In aged rats with estrogen deficiency-induced osteopenia, captopril increased the trabecular area (%BV/TV) of L4 up to 33% and improved biomechanical properties by increasing L5 break stress and elastic modulus when compared to those in the OVX group (P < 0.01). Captopril showed dose-dependent effects on promoting the secretion of ALP and increased mRNA expression of collagen I in the cultured rat osteoblasts. In summary, captopril, one of the most widely used ACEIs, has the potential effects of improving lumbar vertebral bone strength in aged OVX rats and promoting osteoblast bone formation in vitro.

Treating postmenopausal osteoporosis in women at increased risk of fracture - critical appraisal of bazedoxifene: a review

Several categories of drugs to treat osteoporosis exist in the form of bisphosphonates, strontium, parathyroid hormone, and selective estrogen receptor modulators (SERM). Advantages and disadvantages exist for each category as some patients may, for example, not tolerate bisphosphonates for gastrointestinal side effects, and especially in women in whom osteoporosis is frequent, several options for treatment are needed. The objectives of this review were to critically appraise the effects of bazedoxifene on risk of fractures especially in women at high risk of fractures. A systematic literature search was conducted for studies, especially randomized controlled trials with fractures as end-points. Bazedoxifene is a new member of the SERM group. The literature search identified one randomized controlled trial with fractures as end-point. This was a 3-year randomized double-blind placebo controlled trial in which 7492 postmenopausal women aged 55 to 85 years were randomly allocated to 1) bazedoxifene (20 [n = 1886] or 40 [n = 1872] mg/day); 2) raloxifene (60 mg/day, n = 1849); or 3) placebo (n = 1885). The risk of vertebral fractures decreased with both 20 (HR 0.58, 95% CI 0.38 to 0.89) and 40 (HR 0.63, 95% CI 0.42 to 0.96) mg of bazedoxifene per day compared to placebo. There was no reduction in non-vertebral fractures. A subgroup of women with a priori high risk of fractures was identified post hoc. In this subgroup there was a reduction in the risk of non-vertebral fractures with the 20 mg dose of bazedoxifene compared to placebo (HR 0.50, 95% CI 0.28 to 0.90). In the 40 mg bazedoxifene group no significant reduction in non-vertebral fractures was seen in this subgroup (HR 0.70, 95% CI 0.40 to 1.20). In general post-hoc defined subgroup analyses should be interpreted with caution. However, the results indicate that bazedoxifene may be effective in preventing vertebral fractures in postmenopausal women with osteoporosis.

Osteoporosis: "A risk factor for periodontitis"

Aging is one of the major health challenges today. Most of the diseases related to aging, lead to significantly increased morbidity and mortality and higher public expenditure of funds. The interconnection between socio-economic conditions and social vulnerability is reflected in precarious states of health with prominence of high rates of osteoporosis and periodontal disease.Both these diseases have been highlighted in public health because of the impact caused by bone fracture and tooth loss. Thus, the elderly could help live a healthier and more meaningful life with the prevention of these diseases.

Serum bone Gla protein and other biochemical estimates of bone turnover in early postmenopausal women during prophylactic treatment for osteoporosis

Serum bone Gla protein (BGP) and conventional biochemical indices of bone metabolism were determined in 66 early postmenopausal women during a double-blind therapeutic trial performed to investigate the effect of oestrogen, calcium and 1,25 (OH)2D3 on postmenopausal osteoporosis. The biochemical variables were determined before, during and after withdrawal of therapy. We found a very high correlation between serum BGP and serum alkaline phosphatase--a measure of bone formation, less high correlation between serum BGP and the remaining parameters--indices of bone resorption. It is concluded that serum BGP probably reflects bone formation and may prove to be a useful new biochemical marker.

Is cigarette smoking a promotor of the menopause?

All women (n = 11,809) aged 44-53 years from a representative district of Denmark were asked by questionnaire about their date of birth, date of latest menstrual bleeding, possible gynaecological operations, smoking habits, and use of medications. A total of 9,411 (80%) questionnaires were returned. After exclusions because of incomplete information (n = 275), possible surgical menopause (n = 1,270), and treatment with gonadal hormones (n = 2,221), 5,645 women remained suitable for to study. The reproducibility of the information given by these women was excellent as judged by personal interviews of 315 participants. The study population was divided into five 2-year age groups, and the proportion of postmenopausal women among non-smokers and heavy smokers was calculated. Differences in respect to the menopausal status were not observable in the oldest and the youngest two age groups comprising just a few per cent of post-menopausal women. However, heavy smokers in the other two age groups had passed the menopause earlier than the non-smokers (p less than 0.001). This finding suggests cigarette smoking as a promotor of the menopause.

Effect of 1,25-Dihydroxyvitamin D3 on Biochemical Indices of Bone Turnover in Postmenopausal Women

Bone metabolism was estimated by serum alkaline phosphatase (index of bone formation) and fasting urinary excretions of calcium and hydroxyproline (indices of bone resorption) in a group of early postmenopausal women and a group of 70-year-old women, during 12 months' treatment with 1,25-dihydroxycholecalciferol (1,25(OH)2D3), and compared to oestrogen/gestagen treatment or placebo treatment. The groups treated with 1,25(OH)2D3 did not show any change in bone metabolism, neither in bone resorption nor in bone formation, during the treatment period when compared to the placebo group, whereas treatment with female hormones decreased both bone resorption and bone formation.

Dietary calcium intake and blood pressure in normotensive subjects

Epidemiological and prospective studies in man and animals have indicated an inverse relationship between calcium intake and cardiovascular mortality and blood pressure (BP). We have therefore studied the effect of dietary calcium on blood pressure in two groups of women. In a cross-sectional study 103 early postmenopausal women were stratified into three groups according to daily calcium intake calculated from a questionnaire. Both diastolic and systolic blood pressures were identical in the three groups. We thereafter conducted a prospective placebo-controlled trial on the effect of calcium supplementation. Twenty-eight healthy women were randomized to placebo treatment (n = 14) or calcium supplementation 2,000 mg daily (n = 14) for one year. In both groups BP remained at initial levels throughout the study and was identical in the two groups at measurements every three months. We thus conclude that calcium supplementation has no effect on BP in normotensive subjects on a high calcium diet.

Serum alkaline phosphatase during hormone treatment in early postmenopausal women. A model for establishing optimal prophylaxis and treatment in postmenopausal osteoporosis

We propose a new model for use in establishing optimal treatment of postmenopausal osteoporosis. When hydroxyproline is taken as an estimate of bone resorption and alkaline phosphatase (ALP) of bone formation, the model indicates that the difference between hydroxyproline and ALP is reflected in the negative calcium balance, and thus the decline in bone mineral content (BMC). Since BMC increases during oestrogen treatment in postmenopausal women, in whom ALP declines gradually, it is postulated that this only happens because of a rapid decline in hydroxyproline. This decline together with BMC, must be dose-related since changes in ALP are uncorrelated to the oestrogen dose. This model fits the generally accepted opinion that the effect of oestrogen on bone loss in postmenopausal osteoporosis is limited, declines with age, and is dose-related. The model indicates that oestrogen treatment should be introduced early after the menopause in order to obtain the optimum prophylactic effect.

Hormone replacement therapy for osteoporosis: clinical and pathophysiological aspects

The pathogenetic role of oestrogen deficiency in osteoporosis was first postulated by Fuller Albright in 1941 and has subsequently become well established. Hormone replacement therapy prevents menopausal bone loss and is the only treatment which has convincingly been shown to reduce fracture risk at both the spine and hip. The mechanisms by which oestrogens affect bone, however, are poorly understood and many aspects of treatment remain ill-defined, in particular with respect to the duration of therapy and its long-term risks and benefits.

Hypertension is a risk factor for fractures

To study the effects of hypertension and other cardiovascular risk factors on risk of fractures, we carried out a case-control study including 124,655 fracture cases and 373,962 age- and gender-matched controls. The main exposure was hypertension, stroke, acute myocardial infarction, ischemic heart disease, atrial fibrillation, peripheral arterial disease, and deep venous thromboembolism, and the main confounders were use of diuretics, antihypertensive drugs, organic nitrates, vitamin K antagonists, and cholesterol lowering drugs along with other confounders. Hypertension and stroke were the only significant risk factors in both the short-term (OR = 1.27, 95% CI = 1.20-1.34 and 1.24, and 95% CI = 1.16-1.31 for < or = 3 years since diagnosis of hypertension and stroke, respectively) and the long-term (OR = 1.11, 95% CI = 1.00-1.23 and 1.09, and 95% CI = 1.02-1.18 for > 6 years since diagnosis of hypertension and stroke, respectively) perspective. Acute myocardial infarction, atrial fibrillation, and deep venous thromboembolism were all associated with a transient increase in the risk of fractures within the first 3 years following diagnosis. Peripheral arterial disease and ischemic heart disease were not associated with an increased risk of fractures. In conclusion, hypertension and stroke seem to be the major cardiovascular risk factors for fractures, whereas acute myocardial infarction, atrial fibrillation, and deep venous thromboembolism seem to be only minor risk factors. The fracture risk in hypertension may explain why antihypertensive drugs as a class effect are associated with a decreased risk of fractures. These drugs may counter some of the deleterious effects of high blood pressure.

New thoughts about estrogen therapy from the Women's Health Initiative

Since the introduction of hormone replacement therapy (HRT) in 1942, the availability of scientific information regarding the physiologic action of estrogen alone and in combination with progesterone has grown substantially. The specific physiology of changes in endogenous estrogen as a causal factor in bone loss that occurs as the result of menopause is now better understood. Accumulating evidence regarding the benefit of estrogen in protecting against bone loss at the time of menopause made it the first choice for prevention and treatment of osteoporosis, until the findings of the Women's Health Initiative (WHI) were announced in 2002. Fortunately, the availability of multiple alternative agents for prevention and treatment of osteoporosis in menopausal women has provided clinicians with other options. There remain a small number of patients who cannot tolerate or afford these alternative therapies. Recent publications resulting from the WHI should be understood by practicing physicians who are faced with this dilemma and may need to consider HRT in treating patients with osteoporosis.

Rationale for low-dose systemic hormone replacement therapy and review of estradiol 0.5 mg/NETA 0.1 mg

The menopausal transition is associated with several symptoms, for which both non-pharmacological and pharmacological measures are available to provide relief. However, present knowledge indicates that the former is not highly effective, and that the latter, in terms of systemic oestrogen and progestogen-based hormone replacement therapy (HRT), although being effective (e.g. on vasomotor symptoms, bleeding control, bone mineral density, vaginal atrophy and quality of life), can be associated with some caveats. Amongst these are an increased risk for coronary heart disease, breast cancer, venous thromboembolism and stroke. In recent years, literature has indicated a dose dependency for HRT on some of the caveats, hence authorities (Food and Drug Administration, and the European Medicines Agency) and menopause societies (International Menopause Society and North American Menopause Society) now recommend that women deemed in need of HRT should receive the lowest possible dose without compromising the effect of symptom relief. Estradiol 0.5 mg/norethisterone acetate (NETA) 0.1 mg, despite being a lower dose than conventional hormones, is a compound, among a few other low-dose options, that can be used in such therapy. As a first-line oral option, it has demonstrated its effectiveness (which seems comparable to other compounds), with high tolerability and, apparently, no safety concerns, in a 6-month study. Further long-term clinical trials and observational studies are mandatory in order to capture any potential harm as well as to elucidate this compound's full potential. Following a thorough literature search using PubMed and MEDLINE from the earliest publication dates through to January 2008, including results from various types of clinical trials and statements on HRT, we review the rationale for these recommendations. We also review the effects and safety of a novel 'ultra-low-dose' oral continuous combined HRT tablet, estradiol 0.5 mg/NETA 0.1 mg.

Effects of treatment with fluoride on bone mineral density and fracture risk--a meta-analysis

Fluoride has fallen into discredit due to the absence of an anti-fracture effect. However, in this meta-analysis, a fracture reducing potential was seen at low fluoride doses [< or =20 mg fluoride equivalents (152 mg monofluorophosphate/44 mg sodium fluoride)]: OR = 0.3, 95% CI: 0.1-0.9 for vertebral and OR = 0.5, 95% CI: 0.3-0.8 for non-vertebral fractures.

INTRODUCTION

Fluoride is incorporated into bone mineral and has an anabolic effect. However, the biomechanical competence of the newly formed bone may be reduced.

METHODS

A systematic search of PubMed, Embase, and ISI web of science yielded 2,028 references.

RESULTS

Twenty-five eligible studies were identified. Spine BMD increased 7.9%, 95% CI: 5.4-10.5%, and hip BMD 2.1%, 95% CI: 0.9-3.4%. A meta-regression showed increasing spine BMD with increasing treatment duration (5.04 +/- 2.16%/year of treatment). Overall there was no significant effect on the risk of vertebral (OR = 0.8, 95% CI: 0.5-1.5) or non-vertebral fracture (OR = 0.8, 95% CI: 0.5-1.4). With a daily dose of < or =20 mg fluoride equivalents (152 mg monofluorophosphate/44 mg sodium fluoride), there was a statistically significant reduction in vertebral (OR = 0.3, 95% CI: 0.1-0.9) and non-vertebral (OR = 0.5, 95% CI: 0.3-0.8) fracture risk. With a daily dose >20 mg fluoride equivalents, there was no significant reduction in vertebral (OR = 1.3, 95% CI: 0.8-2.0) and non-vertebral (OR = 1.5, 95% CI: 0.8-2.8) fracture risk.

CONCLUSIONS

Fluoride treatment increases spine and hip BMD, depending on treatment duration. Overall there was no effect on hip or spine fracture risk. However, in subgroup analyses a low fluoride dose (< or =20 mg/day of fluoride equivalents) was associated with a significant reduction in fracture risk.

HT update: spotlight on estradiol/norethindrone acetate combination therapy

Abstract: The goal ofpostmenopausal hormone therapy is to alleviate the symptoms that are associated with the loss of estrogen. Many formulations of estrogen and progestin are available, depending on the needs and circumstances of each individual woman. For postmenopausal women, the choice of whether or not to begin therapy requires knowledge of the risks and benefits of estrogen and/or progestin replacement. The purpose of this review is to describe the risks and benefits of hormonal therapy, focusing on estradiol/norethindrone acetate combination therapy.

Ultra low-dose hormone replacement therapy and bone protection in postmenopausal women

OBJECTIVES

The aim of the present study was to evaluate the effects of low doses of hormone replacement therapy (HRT) in normal young postmenopausal women.

METHODS

In an open trial healthy, non-obese postmenopausal women received for 2 years a low-dose continuous combined HRT (LD-HRT) containing 1mg estradiol+0.5 mg norethisterone acetate each pill for 28 days, or 0.5 mg of 17beta-estradiol and 0.25 mg of norethisterone acetate (Ultra low dose, Ultra-LD-HRT) along with 1000 mg of calcium per day. Control group consisted of women receiving only 1000 mg of calcium per day, for 2 years. Menopausal symptoms were evaluated by the Green climacteric scale for the first 12 weeks of the study while bleeding profiles, bone mineral density (BMD) and bone turnover were assessed for 24 months.

RESULTS

LD-HRT and Ultra-LD-HRT were effective in reducing menopausal clinical symptoms. In the control group, BMD significantly (P<0.05) decreased at the spine (-2.8+/-0.2%), and femoral neck (-2.8+/-0.7%). In LD-HRT treated group BMD showed a significant (P<0.05) increase at the spine (5.2+/-0.7%), and femoral neck (2.8+/-0.4%) after 24 months. In the Ultra-LD-HRT treated women spine and femoral neck BMD showed a significant (P<0.05) increase (2.0+/-0.3 and 1.8+/-0.3%, respectively) after 24 months. In these women treated with LD-HRT and Ultra-LD-HRT the BMD values were significantly (P<0.05) different from those measured in calcium-treated women.

CONCLUSIONS

LD-HRT and Ultra-LD-HRT can alleviate subjective symptoms providing an effective protection against the postmenopausal decrease of BMD.

Bone loss in the ovariectomized baboon Papio ursinus: densitometry, histomorphometry and biochemistry

To develop a non-human primate model of systemic bone loss after ovariectomy, 24 ovariectomized (OVX) and eight control (non-OVX) female baboons Papio ursinus were investigated over a period of 48 months using bone mineral density (BMD), iliac crest bone histomorphometry, bone turnover markers, and variables of calcium metabolism. Lumbar spine (L1–L4) BMD measured by dual energy X-ray absorptiometry (DXA) decreased in OVX animals in the first 12 months (−7.6%) and showed a slow trend towards recovery after 24 months. Controls showed a slow increase in spinal BMD over 4 years (+9.7%). Total hip BMD decreased slowly up to 48 months in all animals (OVX −12.6%versus controls −10%); this indicated that OVX had a limited effect on total hip BMD. Forearm BMD did not change. The significant decrease in trabecular bone volume (TBV) of the iliac crest from baseline to 12 months was followed by some recovery. Microarchitectural deterioration of trabecular bone in OVX animals was demonstrated by a decline in trabecular number and an increase in trabecular spacing. These changes were also evident on sections of whole vertebrae, proximal femora and iliac crests. Changes in iliac TBV reflected spinal but not hip BMD changes in the OVX animals. Static and dynamic histomorphometric variables indicated that bone turnover was increased for 36 months following OVX. Controls showed no changes in histomorphometric variables. Bone specific alkaline phosphatase (ALPs) in OVX animals remained elevated throughout the study; osteocalcin (OC) was significantly elevated only at 6 and 12 months, and deoxypyridinoline (Pyr-D) was elevated at 12 months but declined after 24 months. ALPs was thus more sensitive to the long-term effects of OVX than were OC or Pyr-D. Controls showed no changes in bone turnover markers. This study showed consistent deleterious changes in lumbar BMD, bone histomorphometry with microarchitectural deterioration together with altered biochemical markers of bone turnover in the first 12 months after OVX. Since these changes resemble those in post-menopausal women, the non-human primate Papio ursinus is suitable for the study of bone loss in post-menopausal women.

The effect of treatment with a thiazide diuretic for 4 years on bone density in normal postmenopausal women

SUMMARY

We performed a 2-year extension of our previous 2-year randomized controlled trial of the effects of hydrochlorothiazide on bone mineral density. The improvements in bone density seen in the first 2 years were sustained throughout the extension study. Thiazides provide a further option in the prevention of postmenopausal bone loss.

INTRODUCTION

Thiazide diuretics reduce urinary calcium excretion and therefore might prevent osteoporosis. Previously we reported a 2-year randomized controlled trial of hydrochlorothiazide treatment in 185 postmenopausal women that showed positive benefits of hydrochlorothiazide on bone density. Here, we report the results of a 2-year extension to that study.

METHODS

Of 185 healthy postmenopausal women, 122 agreed to continue in a double-blinded 2-year extension taking 50 mg hydrochlorothiazide or placebo daily. Measurements of bone density occurred every 6 months and of calcium metabolism at 2 and 4 years.

RESULTS

The improvements in bone density seen in the first 2 years of the trial were sustained throughout the extension. There were significant between-groups differences in the change in bone density over 4 years at the total body (0.9%, P<0.001), legs (1.0%, P=0.002), mid-forearm (1.1%, P=0.03), and ultradistal forearm (1.4%, P=0.04). At the lumbar spine (0.9%, P=0.76) and femoral neck (0.4%, P=0.53) the between-groups differences did not reach statistical significance.

CONCLUSIONS

Hydrochlorothiazide produces small positive benefits on cortical bone density that are sustained for at least the first 4 years of treatment. They provide a further option in the prevention of postmenopausal bone loss, especially for women with hypertension or a history of kidney stones.

The long-term impact of 2-3 years of hormone replacement therapy on cardiovascular mortality and atherosclerosis in healthy women

OBJECTIVE

The effect of hormone replacement therapy (HRT) on cardiovascular risk is intensely debated. The aim of this study was to investigate the long-term effects of HRT given for a few years on all-cause and cardiovascular mortality and the severity of atherosclerosis.

METHODS

This analysis was based on a cohort of 1,458 postmenopausal women (55.8 +/- 6.1 years old) who previously participated in a number of randomized, placebo-controlled, clinical trials assessing the efficacy of 2-3 years of therapy with various estrogen plus progestin combinations for preventing bone loss. Women were followed on average for 9.8 years and came for a follow-up visit. Outcome variables were all-cause and cardiovascular mortality and the severity of atherosclerosis, as estimated by semi-quantitative scoring of vascular calcification in the lumbar aorta on lateral radiographs.

RESULTS

A total of 174 women died during the observation period. All-cause mortality was decreased by 30% in the HRT+ group compared with the HRT- group (hazard ratio (HR) 0.70; 95% confidence interval (CI) 0.50-0.97) after adjusting for age, body mass index and smoking. Under the same conditions, similar results characterized mortality from cardiovascular disease (n = 61 deaths; 35.1% of all deaths) and coronary heart disease (n = 39 deaths; 22.4% of all deaths), which were decreased by 46% (HR 0.54, 95% CI 0.29-0.98, p = 0.045) and 53% (HR 0.47, 95% CI 0.21-1.03, p = 0.062), respectively. Furthermore, the mean severity score of aortic calcification at follow-up was significantly lower in hormone-treated compared to non-treated women (p < 0.0001).

CONCLUSION

Women who receive 2-3 years of HRT after menopause do not have increased all-cause mortality, and results of the present study suggest relative cardiovascular benefits compared to those who had not used hormones.

Comparison of the effects of a new conjugated oral estrogen, estradiol-3beta-glucoside, with oral micronized 17beta-estradiol in postmenopausal women

The objective of this article is to evaluate the pharmacokinetics of serum estrone and estradiol levels in women who were taking either 17beta-estradiol-3beta-glucoside (E(2)-3beta-glucoside) or 17beta-estradiol (E(2)) daily and to examine the effects of E(2)-3beta-glucoside and E(2) on postmenopausal symptoms, gonadotropins, hepatic metabolism, and coagulation factors. Healthy postmenopausal women on estrogen who had undergone a hysterectomy were recruited. Subjects were randomly assigned to receive equivalent doses of either E(2)-3beta-glucoside or micronized E(2) for 28 days. Pharmacokinetic studies of estrone and estradiol were performed on days 1, 2, 28, and 29. Gonadotropin levels and Kupperman Index (KI) scores were determined at baseline and on treatment day 28. Mean serum estradiol and estrone concentrations in those taking E(2)-3beta-glucoside were comparable with those taking E(2). Mean baseline follicle stimulating hormone (FSH) levels were 84 +/- 27 mIU/mL and 71 +/- 24 mIU/mL in the E(2)-3beta-glucoside and E(2) groups, respectively, with significant decreases (P < 0.01) of 54 +/- 21 mIU/mL and 38 +/-18 mIU/mL, respectively, by treatment day 28. Baseline KI scores in the E(2)-3beta-glucoside group were 10 +/- 6 compared with 5 +/- 4 on treatment day 28, which is equivalent to a 50% reduction in menopausal symptoms (P = 0.003). The change in KI scores in the E(2) group was not statistically significant. Total serum estradiol and estrone levels in women taking E(2)-3beta-glucoside are comparable with those in women taking E(2). E(2)-3beta-glucoside reduces serum gonadotropin levels to the premenopausal range and is effective at reducing postmenopausal symptoms. E(2)-3beta-glucoside is a novel synthetic estrogen that is well tolerated and has promise as a hormone replacement therapy.

Estrogen receptor alpha and beta polymorphisms: is there an association with bone mineral density, plasma lipids, and response to postmenopausal hormone therapy?

OBJECTIVE AND DESIGN

A cross-sectional segregation analysis of polymorphisms in the estrogen receptor (ER) genes (Pvull and Xbal in ERalpha, and Alul in ERAbeta with bone mineral density in the lumbar spine and forearm and with lipid profile was performed in 1098 postmenopausal women. Additionally, in a subpopulation of 280 women, who completed 1 year of treatment with estrogen plus progestin, the association between genotypes and the response to treatment in both plasma lipids and bone was investigated. In another untreated subpopulation of 443 women, genotype influence on the prevalence of vertebral fractures and on annual rate of bone loss during a mean follow-up period of 11 years was estimated.

RESULTS

Baseline plasma lipids, bone mineral density, annual rate of bone loss and prevalence of spinal fractures were not significantly associated with polymorphisms in the ERbeta gene. The ERA polymorphism was significantly associated with bone loss from the distal forearm (P = 0.04) but not with bone loss from the spine. After 1 year of treatment with hormone therapy there was also a significant association between the ERbeta polymorphism and the response in total cholesterol (P = 0.02); while the ERalpha gene polymorphisms did not significantly influence the response to hormone therapy.

CONCLUSIONS

In a large white population of postmenopausal women, ERalpha gene polymorphisms were not associated with bone mineral density or lipid profile at baseline or after hormone therapy. Conversely, the ERbeta genotype appeared to segregate with bone loss from the forearm and to modulate the decrease in total cholesterol during hormone therapy.

Clinical and laboratory safety of one year's use of a combination calcium + vitamin D tablet in ambulatory elderly women with vitamin D insufficiency: results of a multicenter, randomized, double-blind, placebo-controlled study

OBJECTIVE

This article presents the results of an evaluation of the clinical and laboratory safety of a 1-year course of treatment with a combination calcium and vitamin D tablet in ambulatory women aged >65 years with vitamin D insufficiency.

METHODS

In a multicenter, randomized, double-blind, placebo-controlled study conducted in France, women with a 25-hydroxyvitamin D level < or =12 ng/mL were randomized to receive either a combination tablet containing calcium carbonate 500 mg and vitamin D3 400 IU taken twice daily or a matching placebo tablet for 1 year. A complete clinical examination was performed at baseline and at 3, 6, 9, and 12 months of treatment; blood and urine samples were collected for laboratory analyses at the same time points. Safety was monitored based on adverse events recorded during the treatment period and on the results of laboratory tests, including measurement of creatinine and uric acid levels.

RESULTS

The study included 192 women (mean [SD] age, 74.6 [6.9] years; mean weight, 64.0 [12.5] kg), 95 in the calcium + vitamin D group and 97 in the placebo group. Fifty women (21/95 [22.1%] calcium + vitamin D, 29/96 [30.2%] placebo) were prematurely withdrawn from the study for various reasons, with no difference in withdrawals between groups. Treatment-related adverse events were reported in 21 (22.1%) and 23 (24.0%) women in the respective treatment groups. These events consisted mainly of metabolic disorders (9 [9.5%] and 10 [10.4%], respectively), particularly hypercalcemia (6 [6.3%] and 8 [8.3%]) and gastrointestinal disorders (9 [9.5%] and 8 [8.3%]). No major complications directly related to calcium and vitamin D supplementation occurred during the course of treatment. Although renal function was not altered, the group who received calcium + vitamin D had significantly elevated concentrations of serum uric acid compared with those who received placebo (52.3% vs 37.2%; P = 0.046) but not urinary uric acid.

CONCLUSIONS

In these ambulatory elderly women with vitamin D deficiency, supplementation with calcium + vitamin D appeared to be well tolerated over 1 year of treatment. No significant effects on creatinine clearance were observed. However, the proportion of women with elevated serum uric acid concentrations was significantly greater in those who received calcium + vitamin D compared with those who received placebo.

Angiotensin converting enzyme inhibitor use is associated with higher bone mineral density in elderly Chinese

Hypertension and osteoporosis are two major chronic diseases affecting the elderly. A cross-sectional study of 3887 Chinese men (n = 1958) and women (n = 1929) was used to explore the association between angiotensin converting enzyme inhibitor (ACEI) use and bone mineral density (BMD). The participants were aged 65 years and above, and were recruited using a combination of private solicitation and public advertising from community centers, housing estates, and the general community in Hong Kong. Demographic, medical, and lifestyle information was obtained from face to face interviews using standardized questionnaire, and physical examination measurements included anthropometry, tibial, and brachial systolic blood pressures, femoral neck, total hip, and lumbar spine BMD. In multiple regression analyses, after adjusting for age, weight, height, thiazide, beta-blocker, calcium channel blocker, statin, corticosteroid, and calcium supplement use, history of diabetes, heart disease, peripheral vascular disease, cigarette smoking, alcohol intake, and physical activity level, ACEI use was associated with higher femoral neck BMD (+0.015 g/cm2, P = 0.035) in women, and higher femoral neck (+0.015 g/cm2, P = 0.017), total hip (+0.016 g/cm2, P = 0.021), and lumbar spine (+0.043 g/cm2, P < 0.001) BMD in men. Thiazide use was associated with higher BMD at all three sites in general, although associations with BMD increase at the total hip (P = 0.07) and femoral neck (P = 0.09) were weak in men. Calcium channel blocker use was only significantly associated with BMD increase at the lumbar spine (P = 0.03) in women, and beta-blocker use did not have significant associations with BMD at any site. This study suggests that in addition to thiazide diuretics ACEI may have possible benefits in treating not only hypertension but also osteoporosis among older Chinese.

Body mass and risk of hip fracture among a national cohort of postmenopausal white women: a reanalysis

To assess the prospective relationship between body mass and rate of hip fracture, we analyzed data from 2,285 postmenopausal women, aged 50-77 years, who responded to the first National Health and Nutrition Examination Survey (NHANES I) in 1971-1974 and the 1982-84 interview of the National Health Epidemiologic Follow-up Study (NHEFS). We plan to add to the previous analysis of these same data by Farmer et al. by 1) including retrospective information on estrogen replacement therapy; 2) increasing the follow-up time by 5 years and using only hospital-verified cases of hip fracture from the 1987 Health Care Facilities Stay data tape; and 3) limiting the analysis to postmenopausal white women, ages 50-77 years. Results of the multivariable Cox regression modeling showed that women with a baseline body mass index in the highest quartile (> 37 kg/m1.5) experienced a 70% lower rate of hip fracture compared with women in the lowest quartile (< or = 28.7 kg/m1.5)(RR=0.32; 95%CI:0.12, 0.82). Age was positively related to the risk of hip fracture, with the rate over 20% higher per year of age (RR=1.21; 95%CI:1.13, 1.29). Although reported education level, smoking history, physical activity level, and estrogen replacement were significantly (p < 0.0001) associated with body mass index, these covariates were not related to hip fracture in the multivariable analysis. Our findings corroborate earlier results using this same data source, and suggest that interventions aimed at preserving lean mass and consequent bone integrity should be encouraged among women before menopause and maintained through older adulthood.

Raloxifene reduces fractures in postmenopausal women with osteoporosis

Recently, selective estrogen receptor modulators have been developed for the management of osteoporosis based on antiosteoclastic properties similar to that of estrogens but with a safety profile including potential benefits on the breast, heart, and cognitive function. Raloxifene, the first selective estrogen receptor modulator to be marketed for the treatment of osteoporosis has shown reduction in spinal fracture risk in patients with low bone mineral density with (48%) or without (35%) prevalent vertebral fracture. Raloxifene also reduces nonvertebral fractures in high risk patients (47%). The decrease in Type I procollagen N-terminal propeptide at 1 year accounts for 28% of the total reduction in vertebral fracture risk. Raloxifene reduced the risk of estrogen receptor-positive invasive breast cancer by 84%. Among subjects with increased cardiovascular risk at baseline, those assigned to raloxifene had a 40% decrease in the risk of cardiovascular events compared with placebo. The definite anti-fracture efficacy of raloxifene at the spine, its plausible effect on non-spine fracture in high-risk patients and its beneficial effect on breast and heart make this compound an interesting approach for women presenting with osteoporosis.

LEVEL OF EVIDENCE

Therapeutic study, level II (lesser quality randomized controlled trial [eg, < 80% followup, no blinding, or improper randomization]). See the Guidelines for Authors for a complete description of the levels of evidence.

Characterizing the ovotoxicity of cyclophosphamide metabolites on cultured mouse ovaries

Cyclophosphamide (CPA) is reported to target dormant primordial ovarian follicles in rodents and humans. However, mechanistic studies are complicated due to the complex ovarian structure. We present here the characterization of the sensitivity of ovaries to CPA metabolites and the timing of morphological alterations induced by phosphoramide mustard (PM) in an in vitro system. Intact mouse ovaries (postnatal-day-4) were cultured in vitro and exposed to multiple breakdown products of CPA on day 0 (d0). Tissues were cultured up to d8, and then follicle counts and immunohistochemistry were performed. 4-Hydroperoxy-CPA (4-HC), a precursor of an activated form of CPA, and PM depleted primordial and primary follicles (> or =1 microM and > or =3 microM, respectively, p < 0.05); acrolein had effects on follicle numbers only under continuous exposure (> =30 microM); carboxycyclophosphamide and 4-ketocyclophosphamide reduced primordial and small primary follicles only at high concentrations (100 microM). PM-induced follicle loss became significant (p < 0.05) by d1 or d2 following exposures to 10 microM or 3 microM PM, respectively, as determined by the numbers of pyknotic or TUNEL-positive follicles. Cellular targets were oocytes in the smallest follicles, but granulosa cells in large primary follicles. TUNEL staining was observed in both cell types, but caspase-3, a marker of apoptosis, was absent from primordial follicles. In addition, a pan-caspase inhibitor could not prevent follicle losses when administered prior to PM. Thus, brief exposures to 4-HC or PM are sufficient to induce permanent follicle loss in ovaries, and PM is likely the ultimate ovotoxicant. Furthermore, the cell death pathway is likely caspase-independent.

How to manage osteoporosis after the menopause

Many women seek advice about bone health at the time of the menopause. Although fracture probability is low in the majority, treatment may be cost-effective if targeted at those at highest risk. Optimal selection of individuals for intervention is based on a case-finding approach, fracture probability being estimated using a combination of bone mineral density and clinical risk factors. A variety of therapeutic interventions is available for the prevention of osteoporotic fractures in postmenopausal women. Hormone replacement therapy (HRT) is a second-line option in most, although it has a place in the management of perimenopausal women with menopausal symptoms who are at risk from fracture and in other postmenopausal women who express a preference for HRT over other options, after being fully informed about known risks and benefits.

Prevention and treatment of postmenopausal osteoporosis

Osteoporosis is a systemic disease characterized by low bone mass and microarchitectural deterioration of the skeleton leading to enhanced bone fragility and an increased risk of fracture. Prior to fracture, diagnosis is established by documenting low bone mass. In the first section of this article we review the clinical use of bone mass measurements and biochemical markers of bone remodeling in selecting patients most in need of preventive therapy at menopause. Women with high bone turnover lose bone at menopause more rapidly than those with normal bone turnover and are more likely to derive benefit from the several preventive therapies available. The second section addresses the available technologies used to diagnose osteoporosis and/or establish fragility fracture risk using noninvasive bone mass measurement and biochemical markers of bone remodeling separately or in combination. In the third section we review the several treatment options available for patients with osteoporosis, including alendronate (alendronic acid), risendronate (risedronic acid), calcitonin, teriparatide, and raloxifene, and the approaches to monitoring the therapeutic response. The final section deals with fall protection--an often forgotten aspect of management of the patient at risk for sustaining and osteoporotic fragility fracture.

[Current role of hormone replacement therapy in the prevention of postmenopausal osteoporosis: gynecologic point of view]

Hormonal Replacement Therapy (HRT) of the menopause has already proved to be effective in preventing bone loss and reducing the risk of fractures in postmenopausal women. Up until 2002, HRT was widely proposed and prescribed by French practitioners, in particular with regard to the prevention of osteoporosis. The results of two major studies, one American, the Women's Health Initiative (WHI) Study, and the other British, the Million Women Study (MWS), published in July 2002 and August 2003, have called into question the hitherto favourable benefits/risks ratio of HRT after finding an increased incidence of breast cancer and heart disease amongst women undergoing this treatment. Following these studies, the European and French health authorities have issued new recommendations regulating and restricting the use of HRT with a drastic restriction on the indications for its use in the prevention of osteoporosis. These new recommendations are the subject of controversy and pose new problems for practitioners.

Hormone replacement therapy for preventing cardiovascular disease in post-menopausal women

BACKGROUND

There is apparently compelling evidence, from observational studies, that hormone replacement therapy (HRT) may have benefits in reducing cardiovascular events in post-menopausal women. However, these observational data are subject to biases and confounding and require support from formally designed randomised controlled trials of the effects of HRT on cardiovascular disease risk.

OBJECTIVES

To assess the effects of HRT for the primary and secondary prevention of cardiovascular diseases in post-menopausal women.

SEARCH STRATEGY

We searched MEDLINE (1998 to December 2002)), EMBASE (1998 to December 2002), the Cochrane Controlled Trials Register (CCTR) (Issue 4 2002), the National Research Register (1998 to present), Clinical Trials.gov (1998 to present), and the database of Spanish Clinical Trials (1998 to present) and reference lists of articles.

SELECTION CRITERIA

Randomised controlled trials comparing HRT with controls (placebo or no treatment) with a minimum follow up of 6 months for treating or preventing cardiovascular disease in postmenopausal women with or without cardiovascular disease.

DATA COLLECTION AND ANALYSIS

Three independent reviewers extracted information from the articles, solving discrepancies by consensus. All outcomes studied were dichotomous. Risk ratios and 95% confidence intervals (CI) were calculated for each study and plotted. Random effects meta-analysis was used in efficacy outcomes (cardiovascular events) and fixed-effects meta-analysis in variables regarding side effects (deep venous thrombosis).

MAIN RESULTS

No protective effect of HRT was seen for any of the cardiovascular outcomes assessed: all cause mortality, cardiovascular death, non-fatal MI, venous thromboemboli or stroke. Higher risks of venous thromboembolic events (Relative risk (RR) 2.15, 95% CI 1.61 to 2.86), pulmonary embolus (RR 2.15, 95% CI 1.41 to 3.28), and stroke (RR 1.44, 95% CI 1.10 to 1.89) was found in those randomised to HRT compared with placebo. No substantial heterogeneity (p <0.1) was detected in any of the outcomes studied.

AUTHORS' CONCLUSIONS

At present, a recommendation for initiating HRT for the reason of preventing cardiovascular events in post-menopausal women (with or without cardiovascular disease) should not be made. Women with other risk factors for venous thromboembolic events should be discouraged from using HRT if the sole goal is to prevent cardiovascular events.

Response rates to oestrogen treatment in perimenopausal women: 5-year data from the Danish Osteoporosis Prevention Study (DOPS)

OBJECTIVE

To characterise women with no response or with a good response to hormone replacement therapy (HRT), evaluated by change in bone mineral density (BMD).

DESIGN

Nested case-control study within a comprehensive cohort study.

SUBJECTS AND METHODS

In the Danish Osteoporosis Prevention Study (DOPS), perimenopausal women were allocated to either HRT or no HRT. In the present study, we included 466 women who had been treated with HRT for 5 years and 466 untreated women from the same cohort. Non-responders were women in the treatment group, who decreased in BMD more than the mean decrease observed in the untreated group. Good responders were women with a larger increase in BMD than the upper 95% percentile of untreated women. Baseline characteristics were evaluated as predictors of response to HRT.

RESULTS

8.4 and 5.6% were classified as non-responders, whereas 25 and 57% were good responders according to changes in BMD of the femoral neck and lumbar spine, respectively. Combining measuring sites, 2.6% were non-responders and 20% were good responders. Non-responders at the femoral neck were more often smokers and had a lower spine BMD. Good responders were older, had a higher body weight, and higher alcohol consumption. In addition, good responders at both measurements sites had a lower BMD at the total hip.

CONCLUSION

A favourable BMD response to HRT can be expected in most post-menopausal women especially if they are non-smokers with a moderate--as opposed to low--alcohol intake, a high body mass and a low initial hip BMD.

Human races and pharmacogenomics of effective bone treatments

Osteoporosis and its complications represent one of the most important causes of morbidity and mortality around the world. Moreover, its management presents an important economic problem. Although osteoporosis is a worldwide health problem, there are many differences in ethnic groups regarding disease morbidity and drug treatment efficacy. This review analyzed clinical response data of two major osteoporotic treatments (vitamin D and estrogens) regarding four major human races (Asian, Caucasian, Hispanic and Negroid). From clinical studies, Asians seem to be more vitamin-D-sensitive while Caucasians appear more estrogen-sensitive than other human races. Different drug responses may be related to allelic variants in their signaling genes such as those for the vitamin D receptor (VDR) and estrogen receptor-alpha (ER alpha). Some polymorphisms of VDR and ER alpha loci appear to be genetic determinants of osteoporotic risk: ApaI-BsmI-TaqI, FokI variants and poly(A) repeats in VDR; PvuII-XbaI variants and (TA) repeats in ER alpha. Also, because of specific ethnic allele distributions, these VDR and ER alpha polymorphisms may be involved in race differences of osteoporosis treatment responses. Future studies and preventive strategies for the management of osteoporosis need to take into account these racial and genetic factors.