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Context: Phthalates are endocrine-disrupting chemicals that could disrupt normal physiologic function, triggering detrimental impacts on bone., Objective: We evaluated associations between urinary phthalate biomarkers and BMD in postmenopausal women participating in the prospective Women's Health Initiative (WHI)., Methods: We included WHI participants enrolled in the BMD substudy and selected for a nested case-control study of phthalates and breast cancer (N = 1255). We measured 13 phthalate biomarkers and creatinine in 2 to 3 urine samples per participant collected over 3 years, when all participants were cancer free. Total hip and femoral neck BMD were measured at baseline and year 3, concurrent with urine collection, via dual-energy x-ray absorptiometry. We fit multivariable generalized estimating equation models and linear mixed-effects models to estimate cross-sectional and longitudinal associations, respectively, with stratification on postmenopausal hormone therapy (HT) use., Results: In cross-sectional analyses, mono-3-carboxypropyl phthalate and the sum of di-isobutyl phthalate metabolites were inversely associated with total hip BMD among HT nonusers, but not among HT users. Longitudinal analyses showed greater declines in total hip BMD among HT nonusers and with highest concentrations of mono-3-carboxyoctyl phthalate (-1.80%; 95% CI, -2.81% to -0.78%) or monocarboxynonyl phthalate (-1.84%; 95% CI, -2.80% to -0.89%); similar associations were observed with femoral neck BMD. Among HT users, phthalate biomarkers were not associated with total hip or femoral neck BMD change., Conclusion: Certain phthalate biomarkers are associated with greater percentage decreases in total hip and femoral neck BMD. These findings suggest that phthalate exposure may have clinically important effects on BMD, and potentially fracture risk., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

In this large, prospective, observational cohort study of postmenopausal women in the WHI, Cox proportional hazard regression models showed that sodium intake at or near recommended levels is not likely to impact bone metabolism.

Purpose: Teriparatide (TPTD) improves bone mass and microstructure resulting in reduced risk of vertebral and nonvertebral fractures. However, hip bone mineral density improvements are modest and there are no data confirming that TPTD reduces hip fracture risk. To study the effects of TPTD on the proximal femur, we performed a double-blind trial of TPTD vs placebo (PBO) in patients with osteoarthritis from whom femoral neck (FN) samples were obtained at total hip replacement (THR) surgery., Methods: Participants were randomly assigned to receive TPTD or PBO for an average of 40 days before THR. Double tetracycline labeling was initiated 21 days prior to THR to allow histomorphometric assessment of bone formation. During the THR, an intact sample of the FN was procured, fixed, and sectioned transversely. Serum levels of bone turnover markers were measured at baseline and during the THR. Standard histomorphometric parameters were measured and calculated on four bone envelopes (cancellous, endocortical, intracortical, and periosteal). The primary outcome measure was bone formation rate/bone surface (BFR/BS)., Results: Forty individuals were enrolled (25 women, mean age, 71.5 ± 8.0 y and 15 men, mean age, 68.9 ± 7.7 y). In cancellous and endocortical envelopes, BFR/BS was 100% higher in the TPTD vs PBO group (P < .05). Bone turnover markers measured at the time of THR correlated with BFR/BS., Conclusions: TPTD stimulates bone formation rapidly in cancellous and endocortical envelopes of the FN. Our findings provide a mechanistic basis for TPTD-mediated improvement in FN bone mass and ultimately hip strength. This study is the first demonstration of the effect of any osteoporosis medication on osteoblast activity in the human proximal femur.

Context: Citrus fruits contain unique flavanones. One of the most abundant of the flavanones, hesperidin, has been shown to prevent bone loss in ovariectomized rats., Objective: The objective of the study was to measure the effect of hesperidin with or without calcium supplementation on bone calcium retention in postmenopausal women., Design: The study was a double-blind, placebo-controlled, randomized-order crossover design of 500 g hesperidin with or without 500 mg calcium supplement in 12 healthy postmenopausal women. Bone calcium retention was determined from urinary excretion of the rare isotope, (41)Ca, from bone., Results: Calcium plus hesperidin, but not hesperidin alone, improved bone calcium retention by 5.5% (P < .04)., Conclusion: Calcium supplementation (Calcilock), in combination with hesperidin, is effective at preserving bone in postmenopausal women.

Context: Adding progestogens to estrogens changes the risk profile of hormonal therapy for menopausal women, and recent data support the need for progestogen-free options. Several current and evolving approaches to managing estrogen deficiency allow for progestogen omission. We review the mechanisms of estrogen activity and provide an overview of emerging and available estrogen receptor (ER)-based therapies., Evidence Acquisition: PubMed was searched for relevant English-language articles using keywords pertaining to estrogen deficiency, menopause, hormone therapy, and estrogen-only therapy. Pivotal or recent randomized controlled trials, large observational studies, comprehensive meta-analyses, and established therapeutic guidelines were compiled., Evidence Synthesis: Advances in our understanding of ER pharmacology have led to therapies designed to optimize ER activity, including selective ER modulators (SERMs) and tissue-selective estrogen complexes (TSECs). Each estrogen, SERM, and TSEC exhibits a unique profile of tissue-specific activity, spanning the spectrum from ER agonism to antagonism. Systemic estrogens unopposed by progestogens effectively manage menopausal symptoms in hysterectomized postmenopausal women but require progestogen use in postmenopausal women with a uterus. SERMs are effective for managing certain aspects of estrogen deficiency in postmenopausal women, but data suggest that pairing a SERM with estrogens to form a TSEC provides a more optimal therapeutic profile for women with a uterus., Conclusions: Treating signs and symptoms of estrogen deficiency requires an individualized approach based on a woman's goals and the purported risks of different therapies. New and emerging agents have demonstrated efficacy in postmenopausal women with a uterus, while allowing these women to avoid progestogens and their possible adverse effects.

Background: Estrogen therapy (ET) is associated with lower serum calcium and phosphorus concentrations and is known to increase bone mineral density (BMD). Other biomarkers of mineral metabolism may help understand the biological basis of these actions., Methods: We studied 2767 postmenopausal women in the Multi-Ethnic Study of Atherosclerosis, 862 (31%) of whom were using ET. We measured serum concentrations of calcium, phosphorus, 25-hydroxyvitamin D, 24,25-dihydoxyvitamin D, and fibroblast growth factor-23 and urinary fractional excretion of calcium (FEca) and phosphorus (FEphos). We examined the associations of ET with each biomarker. In addition, we tested whether the adjustment for biomarkers attenuated the association of ET with lumbar BMD measured by abdominal computed tomography in a subset of 810 women., Results: In adjusted models, women who used ET were younger in age [62 (SD 8) vs 66 (9) y, P < .001], had lower mean serum calcium [-13 mg/dL (95% confidence interval [CI] -0.17, -0.10), P < .001] and lower FEca [-0.15% (95% CI -0.21, -0.09), P < .001]. Mean serum phosphorus was lower [-0.19 mg/dL (95% CI -0.23, -0.15), P < .001] and FEphos [0.56% (95% CI 0.16, 0.96), P = .007] was higher in women on ET. Mean 25-hydroxyvitamin D and 24,25-dihydroxyvitamin D were higher [1.52 ng/dL (95% CI 0.57, 2.47), P = .002, and 0.26 ng/mL (95% CI 0.03, 0.48), P = .03, respectively] in women who used ET. Mean PTH and fibroblast growth factor-23 did not differ significantly by the use of ET. ET use was strongly associated with higher lumbar BMD [12.75 mg/cm³ (95% CI 7.77-17.73), P < .001]; however, mineral metabolism measures did not meaningfully alter this association., Conclusions: In a multiethnic cohort of postmenopausal women, ET use was associated with lower serum calcium, lower FEca, lower serum phosphorus, and higher FEphos, suggesting these associations are attributable to increased calcium intake into bone and increased urinary phosphorus excretion. ET use was also associated with greater concentrations of vitamin D metabolites. ET-associated differences in these mineral metabolism measures did not meaningfully attenuate the strong association between ET use and lumbar BMD.

Context: The very clinical trial, the Women's Health Initiative, which definitely established the antifracture efficacy of estrogen therapy, led to the demise of estrogen treatment as a viable, long-term option for prevention of bone loss in postmenopausal women due to the well-publicized adverse effects of estrogen plus progestin therapy on a number of nonskeletal endpoints. Given the diminishing clinical use of estrogen, it is logical to question whether estrogen regulation of bone remains a relevant issue at a clinical or basic research level., Evidence Acquisition: Findings of this update are based on a PubMed search and the author's knowledge of the field., Evidence Synthesis: Basic and clinical studies on the mechanisms of estrogen effects on bone will continue to provide potential novel drug targets for the prevention and treatment of osteoporosis. At a clinical level, it is clear that even the low levels of estrogen present in postmenopausal women have a significant impact on bone turnover, leading to a more aggressive approach to prevent bone loss in patients with breast cancer on aromatase inhibitors. Conversely, increasing these low estrogen levels with small doses of estrogen may have beneficial skeletal effects in postmenopausal women without adverse effects on reproductive tissues. Finally, the search continues for new selective estrogen receptor modulators with beneficial effects on bone and other tissues., Conclusions: Even in the post-WHI era, basic and clinical investigation on estrogen and bone will continue to yield important insights that not only expand our knowledge at a basic level but also impact the health of our aging population.

Context: Teriparatide increases both bone formation and bone resorption., Objective: We sought to determine whether combining teriparatide with an antiresorptive agent would alter its anabolic action., Design and Setting: This was a randomized controlled trial conducted in a single university hospital., Patients and Intervention: We randomized 93 postmenopausal women with low bone mineral density (BMD) to alendronate 10 mg daily (group 1), teriparatide 40 microg sc daily (group 2), or both (group 3) for 30 months. Teriparatide was begun at month 6., Main Outcome Measures: BMD of the lumbar spine, proximal femur, proximal radius, and total body was measured by dual-energy x-ray absorptiometry (DXA) every 6 months. Lumbar spine trabecular BMD was measured at baseline and month 30 by quantitative computed tomography. Serum osteocalcin, N-terminal propeptide of type 1 collagen, and N-telopeptide levels were assessed frequently. Women who had at least one repeat DXA scan on therapy were included in the analyses (n = 69)., Results: DXA spine BMD increased more in women treated with teriparatide alone than with alendronate alone (18 +/- 11 vs. 7 +/- 4%; P < 0.001) or both (18+/-11 vs. 12 +/- 9%; P = 0.045). Similarly, femoral neck BMD increased more in women treated with teriparatide alone than with alendronate alone (11 +/- 5 vs. 4 +/- 4%; P < 0.001) or both (11 +/- 5 vs. 3 +/- 5%; P < 0.001). Quantitative computed tomography spine BMD increased 1 +/- 7, 61 +/- 31, and 24 +/- 24% in groups 1, 2, and 3 (P < 0.001 for all comparisons). Serum osteocalcin, N-terminal propeptide of type 1 collagen, and cross-linked N-telopeptides of type I collagen increased more with teriparatide alone than with both (P < 0.001 for each marker)., Conclusion: Alendronate reduces the ability of teriparatide to increase BMD and bone turnover in women.

Introduction: Reduction of ovarian estrogen secretion at menopause increases net bone resorption and leads to bone loss. Isoflavones have been reported to protect bone from estrogen deficiency, but their modest effects on bone resorption have been difficult to measure with traditional analytical methods., Methods: In this randomized-order, crossover, blinded trial in 11 healthy postmenopausal women, we compared four commercial sources of isoflavones from soy cotyledon, soy germ, kudzu, and red clover and a positive control of oral 1 mg estradiol combined with 2.5 mg medroxyprogesterone or 5 mg/d oral risedronate (Actonel) for their antiresorptive effects on bone using novel (41)Ca methodology., Results: Risedronate and estrogen plus progesterone decreased net bone resorption measured by urinary (41)Ca by 22 and 24%, respectively (P < 0.0001). Despite serum isoflavone profiles indicating bioavailability of the phytoestrogens, only soy isoflavones from the cotyledon and germ significantly decreased net bone resorption by 9% (P = 0.0002) and 5% (P = 0.03), respectively. Calcium absorption and biochemical markers of bone turnover were not influenced by interventions., Conclusions: Dietary supplements containing genistein-like isoflavones demonstrated a significant but modest ability to suppress net bone resorption in postmenopausal women at the doses supplied in this study over a 50-d intervention period.

Context: Osteoporosis is common among postmenopausal women; animal studies and human pilot studies support the concept of nitric oxide (NO) donors reducing bone mineral density loss., Objective: The objective of the study was to evaluate whether NO donor, nitroglycerin, prevents postmenopausal bone loss., Design: This was a 3-yr randomized, double blinded, single-center, placebo-controlled clinical trial., Setting: The single-center study was conducted at the University of Medicine and Dentistry-Robert Wood Johnson Medical School (New Brunswick, NJ)., Participants: Participants included 186 postmenopausal women aged 40-65 yr, with lumbar bone mineral density (BMD) T-scores of 0 to -2.5., Intervention: Women, stratified by lumbar T-score (<-1.50 and >or=-1.50) and years since menopause (5 yr), were randomized to receive nitroglycerin ointment (22.5 mg as Nitro-Bid) or placebo ointment received daily for 3 yr. Both groups took 630 mg daily calcium plus 400 IU vitamin D supplements., Measurements: BMD was measured at 6 months and annually by dual-energy x-ray absorptiometry. Percent change in lumbar vertebrae BMD was the primary outcome. Hip BMD, total body bone mineral content, and height were secondary outcomes., Results: After 36 months of therapy, changes of -2.1% in the active group (n = 88) and -2.5% in the placebo group (n = 82) in lumbar spine BMD were seen (P = 0.59; 95% confidence interval -1.001, 1.975). Secondary outcomes also did not differ by intervention arm. The active group reported more headaches compared with the placebo group (57 vs. 14%, P < 0.001). Other adverse and serious adverse events were not different., Conclusions: BMD changes did not substantially differ between postmenopausal women who received the dose of nitroglycerin tested, in comparison with a placebo. Once-daily dosing with 22.5 mg of transdermal-administered nitroglycerin was not effective (compliance adjusted dose was only approximately 16 mg/d); a sub-therapeutic dose.

Context: Genistein aglycone improves bone metabolism in women. However, questions about the long-term safety of genistein on breast as well as its continued efficacy still remain., Objective: We assessed the continued safety profile of genistein aglycone on breast and endometrium and its effects on bone after 3 yr of therapy., Design: The parent study was a randomized, double-blind, placebo-controlled trial involving 389 osteopenic, postmenopausal women for 24-months. Subsequently, a subcohort (138 patients) continued therapy for an additional year., Patients and Interventions: Participants received 54 mg of genistein aglycone daily (n = 71) or placebo (n = 67). Both treatment arms received calcium and vitamin D(3) in therapeutic doses., Main Outcomes: Mammographic density was assessed at baseline, 24 and 36 months by visual classification scale and digitized quantification. BRCA1 and BRCA2, sister chromatid exchange, and endometrial thickness were also evaluated. Lumbar spine and femoral neck bone mineral density were also assessed. Secondary outcomes were biochemical levels of bone markers., Results: After 36 months, genistein did not significantly change mammographic breast density or endometrial thickness, BRCA1 and BRCA2 expression was preserved, whereas sister chromatid exchange was reduced compared with placebo. Bone mineral density increases were greater with genistein for both femoral neck and lumbar spine compared to placebo. Genistein also significantly reduced pyridinoline, as well as serum carboxy-terminal cross-linking telopeptide and soluble receptor activator of NF-kappaB ligand while increasing bone-specific alkaline phosphatase, IGF-I, and osteoprotegerin levels. There were no differences in discomfort or adverse events between groups., Conclusions: After 3 yr of treatment, genistein exhibited a promising safety profile with positive effects on bone formation in a cohort of osteopenic, postmenopausal women.

Context: Serum 25-hydroxyvitamin D (25OHD) concentrations greater than 30 ng/ml have been recommended for lowering fracture risk., Objective: Our objective was to determine whether 25OHD sufficiency is a prerequisite for effective response to teriparatide (TPTD)., Design and Patients: Data were from 1620 osteoporotic postmenopausal women in the Fracture Prevention Trial. The response to TPTD was assessed in women subgrouped by having 25OHD insufficiency (>10 but 30 but 0.10). However, it should be noted that because of the limited number of fractures, this study does not exclude the possibility of differences in fracture outcome between the subgroups., Conclusions: In postmenopausal women with osteoporosis and normal intact PTH, the responses to TPTD did not differ significantly in women with baseline 25OHD insufficiency or sufficiency.

Background: Studies of weight loss and changes in bone mineral density (BMD) have primarily been short-term trials in obese subjects., Objective: We examined the effects of a 5-yr intervention designed to prevent menopausal weight gain or promote modest weight loss on BMD in premenopausal women participating in the Women's Healthy Lifestyle Project., Design: We enrolled 373 premenopausal women (age 44-50 yr) and randomly assigned them to either lifestyle intervention (175 women, low-fat dietary modification, weight loss, and physical activity intervention) or control group (198 women). BMD and body weight were measured at baseline, annual follow-up visits (18, 30, 42, and 54 months), and two postintervention follow-ups (66 and 78 months). BMD was measured by dual x-ray absorptiometry., Results: Over the 54 months of intervention, women in the intervention group lost 0.4 kg, whereas control women gained 2.6 kg (P = 0.011). The intervention group experienced significantly greater hip bone loss (-0.20%/yr) than the control group (-0.03%/yr). During the postintervention, differences in rates of bone loss disappeared. When considering both menopausal status and use of hormone therapy (HT), the annualized BMD changes were lower in women reporting HT use; nevertheless, among women on HT, those who lost more than 3% body weight experienced greater total hip BMD loss (-0.25%/yr) compared with those who gained weight (-0.02%/yr) (P = 0.025)., Conclusions: Women randomized to a lifestyle intervention aimed at preventing menopausal weight gain or promoting modest weight loss experienced greater rates of hip bone loss than control women.

Background: Few data are available on the safety and efficacy of once-weekly oral bisphosphonate therapy in breast cancer survivors., Objective: Our objective was to determine whether risedronate, 35 mg weekly, is efficacious and safe in preventing bone loss associated with chemotherapy-induced menopause., Design: The study was a randomized, double-blind, placebo-controlled clinical trial over 12 months., Setting and Participants: Participants included 87 newly postmenopausal women with status post chemotherapy, recruited from a breast cancer clinic in an academic medical center., Intervention: Participants were randomly assigned to receive risedronate 35 mg/wk or placebo., Main Outcome Measures: The primary outcomes were the 12-month changes in spine and hip bone mineral density. Secondary outcomes included changes in markers of bone resorption (urine N-telopeptide cross-linked collagen type I) and formation (osteocalcin, N-terminal propeptide of type I procollagen, and bone-specific alkaline phosphatase)., Results: After 12 months, bone mineral density increased by 1.2% at the spine and 1.3% at the hip in women on risedronate vs. significant decreases for women in the placebo group of 0.9% at the spine and 0.8% at the hip (P < 0.01, difference between groups). N-telopeptide cross-linked collagen type I, a marker of bone resorption, decreased by 19.3%, and N-terminal propeptide of type I procollagen, a marker of bone formation, decreased by 26.6% in participants on active therapy compared with increases in the control group. Risedronate was well tolerated, and the retention rate was 95% at 1 yr., Conclusions: Risedronate once weekly prevented bone loss and reduced bone turnover in women with breast cancer treated with chemotherapy. Early measures to prevent bone loss should be considered in this cohort of breast cancer survivors.

Purpose: Mortality from breast cancer has decreased in large part because of adjuvant chemotherapy. Sequelae of therapy include ovarian failure and bone loss, loss that would increase these patients' risk of fracture with aging. In this study, we assessed the efficacy of pamidronate in preventing such loss., Patients and Methods: The study was a 1-yr randomized, double-blind, placebo-controlled trial comparing pamidronate 60 mg iv every 3 months with placebo in 40 premenopausal women with newly diagnosed breast cancer. Bone mineral density (BMD) of the spine and hip and remodeling markers were monitored over 1 yr., Results: Over half of the subjects became amenorrheic, and those who did were 4 yr older than those who did not (P = 0.02). The mean difference in percent change in BMD at 12 months between the two treatment groups was 5.1% at the lumbar spine (P = 0.002) in the overall study group and 5% at the lumbar spine and 5.2% at the total hip in the amenorrheic subgroup (P < 0.03). Biochemical markers of bone remodeling did not differ between the two treatment groups, and treatment was well tolerated., Conclusion: Chemotherapy-induced amenorrhea is common with ensuing bone loss at the spine and hip. Pamidronate prevented bone loss at the spine and hip and was well tolerated.

Purpose: To evaluate serum 25-hydroxyvitamin D [25(OH)D] concentrations and factors related to vitamin D inadequacy in postmenopausal North American women receiving therapy to treat or prevent osteoporosis., Methods: Serum 25(OH)D and PTH were obtained in 1536 community-dwelling women between November 2003 and March 2004. Multivariate logistic regression was used to assess risk factors for suboptimal (<30 ng/ml) 25(OH)D., Results: Ninety-two percent of study subjects were Caucasian, with a mean age of 71 yr. Thirty-five percent resided at or above latitude 42 degrees north, and 24% resided less than 35 degrees north. Mean (sd) serum 25(OH)D was 30.4 (13.2) ng/ml: serum 25(OH)D was less than 20 ng/ml in 18%; less than 25 ng/ml in 36%; and less than 30 ng/ml in 52%. Prevalence of suboptimal 25(OH)D was significantly higher in subjects who took less than 400 vs. 400 IU/d or more vitamin D. There was a significant negative correlation between serum PTH concentrations and 25(OH)D. Risk factors related to vitamin D inadequacy included age, race, body mass index, medications known to affect vitamin D metabolism, vitamin D supplementation, exercise, education, and physician counseling regarding vitamin D., Conclusions: More than half of North American women receiving therapy to treat or prevent osteoporosis have vitamin D inadequacy, underscoring the need for improved physician and public education regarding optimization of vitamin D status in this population.

We report the effect of continuous treatment with alendronate for 6 yr vs. placebo in the Early Postmenopausal Intervention Cohort study. A total of 1609 healthy, early postmenopausal women were recruited; we describe results for the 585 women who received continuous placebo or alendronate (2.5 or 5 mg) daily for 6 yr. Bone mineral density (BMD) was evaluated at the lumbar spine, hip, forearm, and total body at baseline and annually thereafter. Bone turnover markers were measured every 6 months from baseline to yr 2 and annually thereafter. Adverse experiences, including upper gastrointestinal events and fractures, were recorded throughout the study. Women receiving placebo experienced progressive decreases in BMD at all skeletal sites. Patients receiving alendronate experienced significant gains in spine and hip BMD that were maintained through yr 6. Significantly greater, dose-related decreases in bone turnover markers in the alendronate groups vs. placebo occurred within the first year and were sustained through yr 6. Women receiving alendronate had adverse experience incidences similar to those receiving placebo. Fractures occurred in 11.5, 10.3, and 8.9% of women taking placebo, 2.5 mg alendronate, or 5 mg alendronate daily, respectively. Therapy with alendronate is an effective and promising strategy for the prevention of postmenopausal osteoporosis.

This study assessed the association of habitual dietary calcium intake and bone loss in early postmenopausal women. Four hundred fifty-four healthy postmenopausal Chinese women were enrolled for this 18-month cohort study. The subjects were 48-62 yr of age and within 12 yr of natural menopause. Dietary intake was assessed by the food frequency method, and bone mass was measured using dual energy x-ray absorptiometry at baseline and 9 and 18 months. The association between mean habitual dietary intake over the follow-up period and the rate of bone loss was examined. During the 18-month follow-up, the total loss rates of BMD at the whole body, lumber spine, femoral neck, and total hip were 1.28, 0.60, 1.54, and 0.56% (all P < 0.01). Subjects were stratified into four quartiles according to calcium intake during the period of follow-up. Quartiles I-IV had median intakes of 341, 505, 682, and 934 mg Ca/d. Subjects in quartile IV had significantly less BMD loss at the whole body and less BMD/bone mineral content loss at Ward's triangle, even after adjustments for confounding factors (by analysis of covariance). Multiple linear regression analyses showed significant positive associations between calcium intake and BMD change at the whole body (P = 0.006) and Ward's triangle (P = 0.021). Calcium intake was significantly associated with bone mineral content change at the trochanter (P = 0.025) and Ward's triangle (P < 0.001). No significant effect of calcium intake at the spine was found. In conclusion, habitual dietary calcium intake had a beneficial effect on bone loss at the whole body and some regions of the hip. Our findings suggest that an intake exceeding 900 mg calcium/d was helpful in the prevention of cortical bone loss among early postmenopausal Chinese women.

High phytoestrogen intake among Asian women has been thought to explain the low risk of bone fractures in these populations. In a randomized placebo-controlled trial we studied the effects of isoflavonoids on urinary output of the N-terminal cross-linked telopeptide of type I collagen, pyridinoline (Pyr), and deoxypyridinoline (Dpyr) (bone resorption markers) and serum levels of bone-specific alkaline phosphatase and N-terminal and C-terminal procollagen type I (bone formation markers). Fifty-five postmenopausal women with a history of breast cancer used phytoestrogens (114 mg of isoflavonoids) or placebo tablets daily for 3 months; the treatment regimens were then crossed over after a 2-month washout period. The markers were measured before and on the last day of each treatment period. Bone resorption was reduced during phytoestrogen use, as reflected in falls in the urinary output of Pyr (9%; P = 0.001) and Dpyr (5%; P = 0.008). Compared with the placebo group, the fall in Dpyr was significant (P = 0.022) and the falls in Pyr (P = 0.084) and N-terminal cross-linked telopeptide of type I collagen (P = 0.082) showed a trend toward significance. Bone formation markers were not affected by this regimen. Thus, isoflavonoid-induced inhibition of bone resorption may contribute to the low risk of osteoporosis in Asian women.

Animal studies have shown that soy isoflavones have an effect in preventing estrogen-related bone loss, but few data are available in humans, especially in the Asian populations. This double-blind, placebo-controlled, randomized trial examines the effects of soy isoflavones on bone loss in postmenopausal Chinese women, aged 48-62 yr. Two hundred and three eligible subjects were randomly assigned to three treatment groups with daily doses of placebo (1 g starch; n = 67), mid-dose (0.5 g starch, 0.5 g soy extracts, and approximately 40 mg isoflavones; n = 68), and high dose (1.0 g soy extracts and approximately 80 mg isoflavones; n = 68). All were given 12.5 mmol (500 mg) calcium and 125 IU vitamin D(3). Bone mineral density (BMD) and bone mineral content (BMC) of the whole body, spine, and hip were measured using dual energy x-ray absorptiometry at baseline and 1 yr post treatment. Both univariate and multivariate analyses showed that women in the high dose group had mild, but statistically significantly, higher favorable change rate in BMC at the total hip and trochanter (P < 0.05) compared with the placebo and mid-dose groups, even after further adjustments for the potential confounding factors. Further stratified analyses revealed that the positive effects of soy isoflavone supplementation were observed only among women with lower initial baseline BMC (median or less). In conclusion, soy isoflavones have a mild, but significant, independent effect on the maintenance of hip BMC in postmenopausal women with low initial bone mass.

Recently several studies in adolescent girls or premenopausal women have implicated the calcium sensing receptor (CASR) gene A986S polymorphism in calcium and bone metabolism. However, the role of this genetic variant in postmenopausal women, specifically the development of osteoporosis, is unknown. This study reports the findings of a randomized, double-blind, placebo-controlled study of healthy postmenopausal women followed for 2 yr while taking placebo or supplementary calcium. Specifically, we examined the relationship between the CASR A986S polymorphism, bone biochemical profile, and bone mineral density at baseline and after 2 yr of treatment. We found no effect of this genetic variant in postmenopausal women at baseline or in response to calcium supplementation. These results are in contrast to those in young or premenopausal women, and they provide no support for an important role for the CASR A986S polymorphism in osteoporosis.

To determine whether estrogen initiated at age 60 yr or later reduces rates of bone loss and fracture incidence, we performed a prospective cohort study of 6910 nonosteoporotic women, 65 yr of age or older. Estrogen use, medical history, lifestyle, and anthropometric data were obtained by questionnaire, interview and examination. We identified five patterns of estrogen use: never users (67%); past early users (started under age 60 yr with no current use; 23%); past late users (started at age 60 or later with no current use; 2%); current early users (started under age 60 yr with use both at baseline and 6 yr later; 6.7%); and current late users (started at age 60 or later with use at baseline and 6 yr later; 1.5%). Bone mineral density was measured at the total hip twice, an average of 3.5 yr apart, and at the calcaneus, an average of 5.7 yr apart. Incident nonspine fractures were validated by radiographic report. Bone mineral density was significantly higher among current users, compared with never and past users. The annual rate of hip bone loss was significantly lower in current early users (-0.22%/yr) and current late users (-0.35%/yr) in comparison with never users (-0.6%/yr), past early users (-0.6%/yr), and past late users (-0.72%/yr). During an average of 11.0 yr of follow-up, 1953 nonspine fractures were confirmed. The multiple-adjusted relative risk of nonspine fracture was 0.63 (95% confidence interval 0.51-0.78) among current early users and 0.75 (0.50-1.12) among current late users, compared with never users. Early initiation and long-term continuation of estrogen is associated with a reduction in the risk of nonspine fractures, and initiation at or after age 60 yr with long-term continuation may also be associated with a reduced fracture risk.

Tibolone, a novel compound with tissue-specific effects, has been found to have antiresorptive properties in bone. To confirm the efficacy of tibolone and determine its minimum effective dose for prevention of bone loss in early postmenopausal women, two randomized, double-blind, placebo-controlled, dose-finding studies were performed. Seven hundred seventy healthy women postmenopausal within 1-4 yr, with normal bone density for their age, were treated for 2 yr with 0.3, 0.625, 1.25, or 2.5 mg tibolone daily or placebo. All subjects took supplemental calcium carbonate (500 mg daily). Bone mineral density (BMD) of the lumbar spine and right proximal femur was measured by dual-energy x-ray absorptiometry for up to 2 yr. At each dose level, except the lowest (0.3 mg), tibolone produced a progressive increase in lumbar spine and total hip BMD over the 2-yr treatment period; at 0.3 mg, total hip density was maintained. However, only the doses 1.25 mg and 2.5 mg produced a progressive increase in femoral neck BMD. The differences in mean percent change from baseline in spine and total hip density were significant (P < 0.05) for all tibolone dose groups compared with placebo at all time points. Tibolone was well tolerated, with a similar overall incidence of adverse events compared with placebo. Tibolone 1.25 mg per day is recommended because it shows a positive and statistically significant change in BMD of spine and femoral neck.

Estrogen deficiency and declining calcium absorption due to reduced calcitriol levels or intestinal resistance to calcitriol, are important factors in the pathogenesis of age-related bone loss. The main objective of this study was to examine the effect of estrogen and 1,25-dihydroxyvitamin D therapy given individually or in combination on bone loss in elderly women. Four hundred eighty-nine elderly women with normal bone density for their age, aged 65-77 yr, were entered into a randomized double blind, placebo-controlled trial. Women were randomized to one of four groups: conjugated estrogens (0.625 mg, daily) to women without a uterus (estrogen replacement therapy) plus medroxyprogesterone acetate (2.5 mg, daily) to women with a uterus (hormone replacement therapy), calcitriol (0.25 microg twice daily), a combination of hormone replacement therapy/estrogen replacement therapy plus calcitriol, or placebos for 3 yr. The primary outcome was the change in bone mineral density of the femoral neck and spine. In the intent to treat analysis, hormone therapy (hormone replacement therapy/estrogen replacement therapy) produced a mean (+/-1 SD) increase in bone mineral density of 2.98% (+/-5.45%) at the femoral neck (P < 0.0001) and 4.36% (+/-6.42%) at the spine (P < 0.0001). There were parallel increases in total hip and trochanter bone mineral density. Calcitriol increased bone mineral density 0.10% (+/- 4.27%) at the femoral neck (P = 0.57) and 1.65% (+/- 4.83%) at the spine (P < 0.0124). The combination of hormone replacement therapy/estrogen replacement therapy + calcitriol increased bone mineral density 3.80% (+/-4.95%) at the femoral neck (P < 0.001), 4.91% (+/-6.0%) at the spine (P < 0.0001), and parallel changes at the total hip and trochanter. All three treatment groups differed significantly from placebo at the spine and for the hormone replacement therapy/estrogen replacement therapy groups at the femoral neck, spine, total hip and trochanter. There were no significant differences between combination therapy and hormone replacement therapy/estrogen replacement therapy alone on bone mineral density at any site in the intent to treat analysis. In a secondary analysis of the effect in women who were adherent to treatment, calcitriol had a more significant effect on spine (P = 0.003) and total hip (P = 0.004). The increase in bone mineral density in the adherent groups of women was always higher compared with the intent to treat groups. Combination therapy compared with hormone replacement therapy/estrogen replacement therapy alone produced a significantly greater response in trochanter (P = 0.007) and total hip bone mineral density (P = 0.0017). In summary, hormone replacement therapy/estrogen replacement therapy alone and in combination with calcitriol therapy was highly effective in reducing bone resorption and increasing bone mineral density at the hip and other clinically relevant sites in a group of elderly women, with normal bone density for their age. Calcitriol was effective in increasing spine bone mineral density. In the adherent women, combination therapy with hormone replacement therapy/estrogen replacement therapy and calcitriol increased bone mineral density significantly more in the total hip and trochanter than did hormone replacement therapy/estrogen replacement therapy alone.

Three hundred and one healthy women between 45 and 65 yr of age and at least 1 yr postmenopausal were randomly assigned to 12-month double-blind therapy with levormeloxifene [1.25 (n = 51), 5, 10, or 20 mg/day], low dose continuous combined hormone replacement therapy [HRT; 1 mg 17 beta-estradiol and 0.5 mg norethisterone acetate/day], or placebo (all n = 50). All of the women were also given a daily supplement of calcium (500 mg). Serum CrossLaps decreased by about 50% in the levormeloxifene groups, with no dose-response effect. The group receiving HRT decreased more (>60%), and the placebo group (500 mg calcium alone) decreased by about 10%. The pattern was similar for bone alkaline phosphatase, except that the decreases were smaller, about 30% for the levormeloxifene groups and 50% for the HRT group. Serum osteocalcin also showed highly significant decreases, of the same magnitude in the levormeloxifene and HRT groups. Spinal bone mineral density (BMD) decreased by less than 1% in the placebo group and increased by about 2% in the levormeloxifene groups and by almost 5% in the HRT group (P < 0.001 for the difference between levormeloxifene and HRT vs. placebo). BMD of the total hip and total body changed in the same direction, although differences between groups were not as pronounced as those for BMD spine. Total cholesterol decreased by about 13--20% during levormeloxifene therapy, whereas daily doses of 1 mg estradiol and 0.5 mg norethisterone acetate produced a decrease of only about 8%. Levormeloxifene decreased low density lipoprotein cholesterol by about 22-30% compared with about 12% in the low dose HRT group. High density lipoprotein cholesterol was unchanged in all groups. Endometrial thickness increased both clinically and statistically significantly in the levormeloxifene groups independently of the dose; the difference from the placebo and HRT groups was significant (P < 0.001). There was no significant difference between the HRT and placebo groups. Other adverse events of interest include hot flushes, which did not occur more frequently in the levormeloxifene than the placebo groups, but occurred significantly less frequently in the HRT group (P < 0.05). Breast tenderness was much more common in the HRT group (<0.001) than in all other groups. In conclusion, the study shows that levormeloxifene, a new selective estrogen receptor modulator, has positive effects on BMD and bone turnover and apparently strong estrogenic effects on the serum concentrations of different cholesterol subfractions. Levormeloxifene at the doses tested had an estrogen-like effect on endometrium and no effect on hot flushes. The study was unable to differentiate between the effects of the different doses of levormeloxifene.

We studied the effect on bone mass of alendronate treatment for 5 yr and its withdrawal. Four hundred and forty-seven postmenopausal women with normal bone mass entered a 3-yr randomized trial followed by a 2-yr open label extension. Three hundred and eleven women completed the first 3 yr, and 263 consented to continue and completed the extension. We are reporting data from groups using the dose of alendronate currently approved for osteoporosis prevention (5 mg) or from the group in which alendronate treatment was withdrawn: 52 women received alendronate (5 mg) for 5 yr (group I), 56 received 3 yr of placebo followed by alendronate (5 mg) for 2 yr (group II), and 52 received alendronate (20 mg) for 2 yr followed by 3 yr off therapy (group III). In group I, alendronate (5 mg) increased bone mineral density (BMD) at the spine and trochanter by 2.5-3.2% (P < 0.001 vs. baseline) and stabilized total body and femoral neck BMD (change vs. baseline, P = NS) over 5 yr. By the end of 5 yr, BMD was comparable at the spine, hip, and total body in groups I and III. The 3-yr decrease in BMD after withdrawal of alendronate (20 mg) in group III was 1.8-5.7% (P < 0.01 vs. baseline) and similar to the 3-yr decrease in BMD in group II during the initial 3 yr. In conclusion, alendronate (5 mg) for 5 yr or alendronate (20 mg) for 2 yr followed by 3 yr off therapy prevented postmenopausal bone loss. After withdrawal of alendronate (20 mg), bone loss resumed at the normal early postmenopausal rate.

Black women have lower levels of serum 25-hydroxyvitamin D (25OHD) with higher serum PTH levels than white women. Correction of these alterations in the vitamin D-endocrine system could lead to less bone loss in postmenopausal women and, consequently, preservation of bone mass. Ten healthy postmenopausal black women were given 20 microg vitamin D3 daily for 3 months. At the end of the study, mean serum 25OHD levels had increased from 24 to 63 nmol/L. Serum intact PTH and nephrogenous cAMP declined significantly, and there was a 21% drop in the fasting urinary N-telopeptide of type I collagen. Vitamin D3 supplementation raises serum 25OHD levels in postmenopausal black women, decreases secondary hyperparathyroidism, and reduces bone turnover. These findings should spur further investigation of the use of vitamin D supplementation in the prevention of osteoporosis in this population.

To establish whether biochemical markers could be used to monitor alendronate (ALN) treatment and predict long-term response in bone mass, we used results from an ongoing, randomized trial of ALN treatment for prevention of postmenopausal osteoporosis (n = 1202). In women treated with ALN (5 mg), change from baseline at month 6 in urine N-telopeptide cross-links of type I collagen (NTX) and osteocalcin (OC) correlated with change from baseline at month 24 in spine, hip, and total body bone mineral density (BMD) [r = -0.28 to -0.31 (NTX) and r = -0.16 to -0.25 (OC), P<0.001]. This corresponded to a 4- to 5-fold greater increase at month 24 in BMD in the tertiles, with the greatest decrease at month 6 in NTX or OC. In women treated with ALN (5 mg) who had a change at month 24 in spine BMD of at least 0%, 86% (NTX) and 79% (OC) had a decrease at month 6 of at least 40% (NTX) or 20% (OC) (sensitivity). The corresponding specificities were 48% (NTX) and 53% (OC). In conclusion, change at month 6 in NTX and OC, in groups of women treated with ALN, indicated the numeric long-term response in BMD within these groups. In individual women, a decrease at month 6, in NTX or OC below the cut-point, validly identified women who responded, on ALN treatment, with a stabilization or an increase in bone mass. However, lack of decrease below the cut-point in NTX or OC could not be used to identify women with a bone loss during ALN treatment.

This study used a cross-sectional design to investigate relationships among serum insulin-like growth factor (IGF) parameters (total serum IGF-I, IGF-II, and IGF-binding protein-3), serum estradiol, and bone mineral density (BMD) stratified for potential confounders, and a longitudinal design to investigate the effects of hormonal replacement therapy (HRT) on IGFs and BMD. Five hundred and ninety-five perimenopausal women (median age, 50.0 yr; range, 45-56 yr) participating in the Danish Osteoporosis Prevention Study were investigated in a cross-sectional study, and a randomly selected subgroup of 110 was followed after 5 yr in a longitudinal study for changes in serum IGFs and BMD of lumbar spine, femoral neck, and ultradistal forearm during (n = 46) or without HRT (n = 64). In the cross-sectional study, serum IGF-I correlated positively to distal forearm BMD and spine BMD, but not to femoral neck BMD, after stratification for age, body mass index, and other variables. In the follow-up study, HRT decreased IGF-I and IGF-II, but did not influence the age-related decline in IGF-binding protein-3 significantly. Serum alkaline phosphatase and urinary hydroxyproline/creatinine ratio both decreased during HRT, whereas BMD increased compared to control values. After adjustment for age, body mass index, treatment, and other factors, IGF-I correlated positively to changes in forearm and femoral neck BMD, but not to changes in spine BMD. We conclude that serum IGF-I was positively associated to bone mineral density. Oral HRT decreases IGF-I and IGF-II.

In sum, the skeletal benefits provided by hormone replacement therapy are important, and estrogen should be justifiably considered one of the fundamentals of menopausal management. However, its efficacy in the prevention of osteoporotic fractures should not be overstated. Low bone mass and fractures remain serious threats in older postmenopausal women, even in the presence of hormone replacement. With the recognition of that reality comes a variety of challenges to clinicians and investigators. Clinicians should use estrogen to its best advantage, though, at the same time, remain vigilant of its limitations. Older postmenopausal women who are, or who have been, taking estrogen should not be a priori considered adequately protected against fracture. The same careful clinical evaluation recommended for the protection of those at increased fracture risk, including bone mass measures, should be available to estrogen-taking women in the later postmenopausal period. Recognizing this need, the National Osteoporosis Foundation has recently recommended bone mineral density testing in older women, regardless of estrogen status, and HCFA reimbursement has become available for this indication. In the presence of low bone density, estrogen-taking women should be afforded appropriate levels of diagnostic and therapeutic attention, with the intent to further reduce fracture risk. Once estrogen therapy has been elected, patients and their clinicians should be aware that bone loss can still be expected in the later postmenopausal years. Periodic reevaluations of bone density and other risks for fracture (e.g. falls) may be appropriate. In the face of continued good health, those reevaluations can be infrequent, but women who have medical conditions associated with adverse skeletal effects should be followed more closely despite their estrogen therapy. If we are to build on the value of estrogen to improve our approach to osteoporosis, additional data are needed. When fracture risk has been considered in complex models that adjust for account other medical and lifestyle variables, a greater protective effect of estrogen has emerged (12), suggesting that there are factors whose actions attenuate those of estrogen. Prominent candidates include genetics, tobacco and alcohol use, medications, body composition, and propensity to fall. There are undoubtedly others yet unidentified. These should be further defined, and the basic mechanisms for interactions between them and estrogen should be examined. It would be clinically advantageous to use these factors to accurately identify not only the women who would benefit from estrogen replacement but also those who would not. Because estrogen has important beneficial effects, an essential research objective should be the development of therapeutic strategies that combine the advantages of estrogen with other modalities (pharmacological or otherwise), to maximally protect the many estrogen-taking women who may be considered at continued risk for fracture. To whit, the initial reports of combination therapy with bisphosphonates are encouraging (13, 14). Other important skeletal agents can be anticipated to interact with estrogen in as-of-yet unforeseen ways. On another front, it can be anticipated that selective estrogen receptor modulators will be subject to estrogen-like limitations when used for osteoporosis prevention/therapy, and their effects will be influenced by a similar, but distinct, array of covariates. Our vision of the role of hormone replacement in the reduction of osteoporotic fracture risk should be considerably sharpened. At one time, estrogen was the lone best hope for the avoidance of fracture, but no longer should we be satisfied with that imperfect solution. The development of much more efficient and effective methods for osteoporosis risk assessment, prevention, and treatment now provides a chance to surpass previous expectations. (ABSTRACT TRUNCATED)

The long term effects of hormone replacement therapy (HRT) and vitamin D3 (Vit D) on bone mineral density (BMD) were studied. A total of 464 nonosteoporotic early postmenopausal women from the Kuopio Osteoporosis Study (n = 13100) were randomized to four groups: 1) HRT (sequential combination of 2 mg estradiol valerate and 1 mg cyproterone acetate, 2) Vit D3 (300 and 100 IU/day during the fifth year), 3) HRT and Vit D combined, and 4) placebo. Lumbar (L2-L4) and femoral neck BMD were determined by dual x-ray absorptiometry (DXA) at baseline and after 2.5 and 5 yr of treatment. Intention to treat analysis (n = 464) showed that after 5 yr, lumbar BMD remained unchanged in the HRT and HRT plus Vit D groups [+0.2% (P = 0.658) and +0.9% (P = 0.117), respectively], whereas lumbar BMD decreased by 4.6% in the Vit D group and by 4.5% in the placebo group (P < 0.001 in both). The loss of femoral neck BMD was less in the HRT (-1.4%; P = 0.005) and HRT plus Vit D (-1.3%; P = 0.003) groups than in the Vit D and placebo groups (-4.3%; P < 0.001 in both). Among those 370 women who complied with the 5-yr treatment, the effect was more pronounced: lumbar BMD had increased by 1.5% in the HRT (P = 0.009) and by 1.8% in the HRT plus Vit D group (P = 0.005), with a plateau after 2.5 yr, whereas lumbar BMD had decreased in both the Vit D and placebo groups (4.6% and 4.7%; P < 0.001, respectively). Femoral neck BMD decreased again less in the HRT (-0.4%) and HRT plus Vit D (-0.6%) groups than in the Vit D and placebo groups (-4.4% in both). This study confirms the positive long term effect of HRT on BMD also seen in intention to treat analysis. The data suggest that low dose vitamin D3 supplementation does not prevent bone loss in healthy, nonosteoporotic, early postmenopausal women, and it confers no benefit additional to that of HRT alone.

Elderly women are at increased risk for bone loss and fractures. In previous cross-sectional and longitudinal studies of women residing in northern latitudes, bone loss was most pronounced during winter months and in those consuming less than 1 g calcium per day. In this study we sought to test the hypothesis that calcium supplementation by either calcium carbonate or dietary means would prevent seasonal bone loss and preserve bone mass. Sixty older postmenopausal women without osteoporosis were randomized to one of three treatment arms: Dietary milk supplementation (D-4 glasses of milk/day), Calcium carbonate (CaCO3-1000 mg/day in two divided doses), or placebo (P). After 2 yr, placebo-treated women consumed a mean of 683 mg/day of calcium and lost 3.0% of their greater trochanteric (GT) bone mineral density (BMD) (P < 0.03 vs. baseline); Dietary supplemented women averaged a calcium intake of 1028 mg/day and sustained minimal loss from the GT (-1.5%; P = 0.30), whereas CaCO3-treated women (total Ca intake, 1633 mg/day) suffered no bone loss from the GT and showed a significant increase in spinal and femoral neck BMD (P < 0.05). Femoral bone loss occurred exclusively during the two winters of the study (i.e. total loss, -3.2%; P < 0.02 in placebo-treated women) with virtually no change in GT BMD during summer. Serum 25-OH vitamin D declined by more than 20% (P < 0.001) in all groups during the winter months but returned to baseline in summer; PTH levels rose approximately 20% (P < 0.001) during winter but did not return to baseline during the summers. Urine N-telopeptide and osteocalcin levels increased significantly but only in the P-treated women and only during winter. Serum insulin growth factor binding protein 4, an inhibitory insulin growth factor binding protein, rose 15% (P < 0.03) from summer to winter, but this increase was significant only in those women consuming <1000 mg/day of calcium. By multivariate analysis, total calcium intake was the strongest predictor of bone loss from the hip. Urinary N-telopeptide also closely correlated with GT BMD but only during winter (P = 0.003). We conclude that calcium supplementation prevents bone loss in elderly women by suppressing bone turnover during the winter when serum 25-OH vitamin D declines and serum PTH increases. The precise amount of calcium necessary to preserve BMD in elderly women requires further studies, although in this study, at least 1000 mg/day of supplemental calcium was adequate prophylaxis against femoral bone loss.

This double-blind, placebo-controlled study was undertaken to determine 1) the efficacy of oral risedronate for prevention of bone loss in healthy, early postmenopausal patients with normal bone mass, 2) the effect on bone mass when treatment was stopped, and 3) the safety and tolerance of risedronate in this population. A group of 111 patients were randomized to oral placebo, risedronate 5 mg daily, or risedronate 5 mg cyclically, for 2 yr followed by 1 yr off treatment. Measurements included percentage change from baseline in lumbar spine bone mineral density (BMD) at 24 months; percentage change from baseline in BMD of the femoral neck, trochanteric region, and Ward's triangle region of the proximal femur; and changes in biochemical markers of bone turnover. After 2 yr, there was a mean increase in BMD of the lumbar spine of 1.4% from baseline and of 5.7% vs. placebo in the risedronate 5 mg daily group. There were decreases from baseline in BMD of 1.6% and 4.3% in the risedronate 5 mg cyclic and placebo groups, respectively. By the end of 24 months, trochanteric bone mass at the hip increased by 5.4% in the risedronate 5 mg daily group and by 3.3% in the risedronate 5 mg cyclic group vs. placebo. Bone mass was maintained at the femoral neck in the 2 active-treatment groups vs. a 2.4% mean loss with placebo. During the treatment-free follow-up, bone turnover increased toward baseline in both risedronate groups. By the end of that year, lumbar spine bone mass in all 3 groups was lower than at baseline. Oral risedronate was well tolerated. We conclude that risedronate (5 mg daily) increases bone mass and risedronate (5 mg cyclic) appears to prevent bone loss in early postmenopausal women with normal BMD.

The objective of the study was to evaluate the effects of cyclical therapy with etidronate and calcium on spinal and femoral bone loss in the early post menopausal period. Fifty-four women, 53 +/- 2.8 yr old (mean +/- SD) and 2.3 +/- 1.3 yr post menopause received oral doses of either 400 mg/day etidronate for 2 weeks followed by 500 mg/day elemental calcium for 11 weeks, or placebo for 14 days followed by calcium for 11 weeks, repeated over a total of 24 months. A statistically significant increase in spinal bone mineral density (BMD) was observed after 6 months in the etidronate group. At 2 yr, the mean treatment differences in spinal and femoral neck BMD were +2.93% (P < 0.02) and 2.02% (P < 0.03), respectively. Serum osteocalcin and urinary crossLaps/creatinine excretion were decreased significantly by etidronate. Etidronate was well tolerated with a safety profile similar to that of placebo. Thirty-seven women participated in a 1-yr open-label follow-up study. Twelve months after treatment withdrawal, spinal BMD in the former etidronate group decreased by 1.43% and serum osteocalcin and urinary crossLaps returned to pretreatment values. In conclusion, cyclical etidronate is an effective therapy for the prevention of both trabecular and cortical bone loss in the early menopause and has a good safety profile.

The aim of the study was to assess the effects of 2 yr of treatment with two dose levels of tibolone on bone mineral density and bio-chemical markers of bone metabolism in late postmenopause. Ninety-one healthy women, more than 10 yr after menopause, entered a 2-yr double blind, randomized, placebo-controlled study of treatment with either 1.25 mg/day (n = 36) or 2.5 mg/day (n = 35) Tibolone or placebo (n = 20). Densitometry and determinations of biochemical markers of bone metabolism in serum and urine were performed before randomization and every 3 months during the study. The results revealed a steady and equal increase in bone mineral density in both tibolone groups at the bone sites studied. Gains in BMD spine of 5.9 +/- 0.9% in the 1.25 mg group, 5.1 +/- 0.9% in the 2.5 mg group, and 0.4 +/- 1.1% in the placebo group were found. In the forearm, increases of 2.2 +/- 0.7% in the 1.25 mg group and 1.9 +/- 1.1% in the 2.5 mg group were detected, whereas the placebo group lost 2.1 +/- 1.0%. This was fully supported by changes in biochemical markers of bone resorption (urinary excretion of fragments from the osteoclastic degradation of the alpha 1-chain of the C telopeptides of type 1 collagen and hydroxyproline) and bone formation (serum osteocalcin), respectively. In conclusion, within 2 yr of treatment, tibolone increases bone mass in the spine and prevents bone loss in the forearm in late postmenopausal women determined by densitometry and several biochemical parameters of bone turnover. Tibolone at two doses (1.25 and 2.5 mg/day) had similar effects, indicating that even lower doses may be efficacious.

Although controversies exist on the possible adverse effect of T4 on bone mass, most studies reported bone loss in estrogen-deprived postmenopausal women taking suppressive doses of T4. We prospectively studied 46 postmenopausal women with carcinoma of thyroid for 2 yr to evaluate the rate of bone loss and assess whether calcium supplementation with or without intranasal calcitonin was able to decrease the rate of bone loss. All patients were receiving a stable dose of L-T4 (170 +/- 60 micrograms/day or 3.0 +/- 1.4 micrograms/kg.day) for more than 1 yr. All had TSH levels of 0.03 mIU/L or less and an elevated free T4 (FT4) index, but normal T3 levels. The calcium intake was low and averaged 507 +/- 384 g/day as assessed by dietary recall. The subjects were randomized into three groups: 1) intranasal calcitonin (200 IU daily) for 5 days/week plus 1000 mg calcium daily, 2) calcium alone, or 3) placebo. Total body and regional bone mineral density were measured by a dual energy x-ray absorptiometry bone densitometer at 6-month intervals. The results showed that both groups 1 and 2 had stable bone mass, whereas patients in groups 3 showed significant bone loss at the end of 2 yr (lumbar spine, 5.0%, hip, 6.7%, trochanter, 4.7%; Ward's triangle, 8.8%; P < 0.05), with bone mineral densities at all four regions lower than those in the other two groups (P < 0.05). There were no differences between groups 1 and 2. All three groups had elevated osteocalcin levels compared with age-matched reference controls. At 1 yr, the osteocalcin level decreased in groups 1 and 2, but remained significantly raised in group 3. No significant changes were detected in the bone-specific alkaline phosphatase levels. Urinary hydroxyproline excretion increased in group 3 at the end of 2 yr, but remained the same in groups 1 and 2. In conclusion, T4-suppressive therapy was associated with bone loss in postmenopausal women, which could be prevented by either calcium supplementation or intranasal calcitonin, although the latter did not provide additional benefit compared to calcium alone. However, careful titration of T4 dosage to maintain biochemical euthyroidism is a better way to avoid the adverse effect of T4 on bone.

To elucidate the role of PTH in postmenopausal bone loss, we studied 33 postmenopausal patients who received total thyroidectomy due to thyroid carcinoma. Among these patients, 13 were patients with hypoparathyroid function (HPf), and 20 retained normal parathyroid function (NPf) after thyroidectomy. Bone mineral density (BMD), the rate of BMD loss, and incidence of spinal deformity as well as varying bone metabolic markers were analyzed in all patients. The age-matched BMD was clearly higher, and the incidence of spinal deformity was significantly lower in HPf than in NPf. The rate of BMD loss in HPf was significantly lower than in NPf during the early postmenopausal period (within 5 yr after menopause; mean +/- SD, -0.567 +/- 3.05% vs. -2.49 +/- 1.86%/yr, P < 0.05). In contrast, the rates were similar between the two groups during the late postmenopausal period (> 5 yr after menopause). Bone metabolic markers indicated that an accelerated bone turnover occurred during the early postmenopausal period in NPf, but not in HPf. These results suggest that the hypoparathyroid condition provides protection against age-related bone loss. This is due in part to attenuation of the high turnover bone loss that occurs early in menopause.

The purpose of the study was to determine the effect of vitamin D supplementation on bone turnover and bone loss in elderly women. Three hundred forty-eight women, ages 70 yr and older, were randomized to receive 400 IU vitamin D3 per day (n = 177) or placebo (n = 171), double-blind, for a period of 2 yr. Main outcome measures were bone mineral density of both hips (femoral neck and trochanter) and the distal radius, as well as biochemical markers of bone turnover. The effect of vitamin D supplementation was expressed as the difference in mean (percentage) change between the placebo group and the vitamin D group. The measurements were repeated in 283 women after 1 yr and in 248 women after 2 yr. Vitamin D supplementation significantly increased serum 25-hydroxyvitamin D (250HD) (+35 nmol/L) and 1,25-dehydroxyvitamin D [1,25-(OH)2D] (+7.0 pmol/L) levels and urinary calcium/creatinine ratios (+0.5%) and significantly decreased PTH(1-84) secretion (-0.74 pmol/L) after 1 yr. No effect was found for the parameters of bone turnover. The effect on the bone mineral density of the left femoral neck was +1.8% in the first yr, +0.2% in the second yr, and +1.9% during the whole period (95% confidence interval 0.4, 3.4%). At the right femoral neck the effects were +1.5%, +1.1%, and +2.6% (confidence interval 1.1, 4.0%), respectively. No effect was found at the femoral trochanter and the distal radius. Supplementation with 400 IU vitamin D3 daily in elderly women slightly decreases PTH secretion and increases bone mineral density at the femoral neck.

To study the influence of excess body weight on vertebral postmenopausal bone loss, 155 healthy early postmenopausal women were divided into 2 groups according to their body mass index (BMI = weight/height2) and prospectively followed over a mean 31-month period. Spinal (L2-L4) bone mineral density was measured by dual photon absorptiometry. The annual rate of vertebral bone loss (percentage) was significantly reduced (-0.54 +/- 1.1% vs. -1.46 +/- 1.6%; P < 0.05) in the overweight group (BMI, > or = 25; n = 40) compared to that in the normal weight group (BMI, < 25; n = 115). At baseline, a significant decrease in the urinary calcium/creatinine ratio was observed in the overweight group, which suggested a decrease in bone turnover. A significant correlation was found between the annual rate of bone loss and the BMI (r = 0.21; P < 0.05), but not the body weight. The positive correlation between vertebral postmenopausal rate of bone loss and BMI was confirmed after adjustment for age and time since menopause. Moreover, plasma dehydroepiandrosterone sulfate levels were higher in the high BMI group than in the normal BMI group (P < 0.05). We conclude that within the first years after menopause, moderate excess body weight significantly reduces vertebral postmenopausal bone loss. This effect is probably related to excess adipose tissue through increased conversion of estrogen from adrenal precursors and/or increased production of adrenal androgens.

To study the effect of calcium supplementation on perimenopausal bone loss, 295 women were randomized into a control group and 2 supplementation groups receiving, respectively, 1000 and 2000 mg elemental calcium/day for a period of 2 yr. We observed a significant decrease in lumbar bone loss in relation to the calcium supplementation (mean loss after 2 yr of 3.5% in the control group vs. 1.3% and 0.7% in the 1000 and 2000 mg groups, respectively), a significant increase in urinary calcium excretion, and a significant decrease in the urinary hydroxyproline/creatine ratio, serum alkaline phosphatase, osteocalcin, and 1,25-dihydroxyvitamin D. The effect of calcium supplementation on lumbar bone loss was significant in the first year of supplementation, but not in the second. However, the urinary hydroxyproline/creatinine ratio and the serum alkaline phosphatase level remained significantly decreased in the treatment groups at the end of the study; this was not the case for serum osteocalcin. Calcium supplementation did not have a significant effect on metacarpal cortical bone loss. The difference in biochemical parameters between the 2 supplementation groups was small. No significant interaction was observed between the menopausal status of the subjects and the effect of calcium supplementation. We conclude that calcium supplementation retards lumbar bone loss in the first year of calcium supplementation by reducing bone turnover. However, the effect on lumbar bone loss over a longer time span is still uncertain.