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J Nieves

Publications and source records attributed to J Nieves.

At least 19 recordsLinked to original sources

Biochemical responses of bone metabolism to 1,25-dihydroxyvitamin D administration in black and white women.

The basis for the racial difference in bone mass between black and white women is not known. Lower bone turnover, better renal calcium conservation, and decreased sensitivity to parathyroid hormone (PTH) have been proposed as explanations. A dynamic comparison of osteoblast function, utilizing stimulation by 1,25-dihydroxyvitamin D [1,25(OH)2D], has not been tested between these two ethnic groups. We compared well-matched black (n = 15) and white (n = 15) premenopausal women, before and during 5 days of 1,25(OH)2D administration (1.0 microgram/day) in order to assess dynamic indices of bone metabolism. As expected, at baseline, black women had lower levels of serum 25-hydroxyvitamin D and biochemical markers of bone turnover with slightly higher levels of PTH. Black women also had superior renal calcium conservation than white women at baseline. In response to 1,25(OH)2D administration, black women had a slightly greater increase in serum calcium and greater decrement in PTH. Moreover, black women showed a lesser increment in urinary calcium than white women and a more robust increase in two markers of bone formation--osteocalcin and carboxyterminal propeptide of type 1 procollagen--than white women. There were no changes in bone resorption indices in either race upon 1,25(OH)2D administration. These data provide preliminary evidence that black women conserve calcium more efficiently under both static and dynamic conditions, and also appear to have better osteoblastic functional reserve than white women.

Adult↗

Parathyroid hormone secretory response to EDTA-induced hypocalcemia in black and white premenopausal women.

One consistent racial difference in mineral homeostasis is increased efficiency of renal calcium conservation in blacks which could account, in part, for differences in bone density and fracture risk. Since parathyroid hormone (PTH) is the major regulator of calcium homeostasis, we investigated its secretion in black and white women in response to hypocalcemia. Two hour EDTA infusions (50 mg/kg) were performed in 34 premenopausal women (17 black, 17 white). Blood was sampled at 30-minute intervals during the infusion, at 60-minute intervals for 3 more hours, and at 24 hours. Serum ionized calcium decreased identically in both groups with a nadir at 2 hours and returned to baseline within 24 hours. Serum 1-84 PTH levels rose similarly in both groups with a peak PTH level that was slightly higher in black women, and on average, slightly earlier than that in white women. Serum PTH levels remained elevated in both groups at 24 hours with no overall group differences in PTH response. In black, but not white women, serum 25OHD levels correlated negatively with both basal PTH and peak PTH level, achieved with infusion. Serum 1, 25(OH)(2)D levels rose and osteocalcin levels decreased, with no group differences. We conclude that overall, premenopausal black women show no clear differences in PTH secretory activity to an EDTA-induced hypocalcemic stimulus. Basal vitamin D status appeared to be a determinant of the degree of the PTH response in black women, with the peak PTH level being inversely correlated with levels of 25OHD. Since we have previously shown that the skeleton contributes less to acute calcium needs in blacks than in whites, the lack of a racial difference in PTH secretory responsivity suggests that calcium homeostasis is more likely maintained in blacks through greater PTH sensitivity at extraskeletal sites, such as the kidney.

Adult↗

Parathyroid responsivity in postmenopausal women with osteoporosis during treatment with parathyroid hormone.

Endocrine systems may be affected permanently by administration of supraphysiologic doses of hormone. This is a well known complication of glucocorticoid treatment where the pituitary/adrenal axis may never fully recover, especially when large doses of steroids are needed during significant physical stress. The goal of this investigation was to determine whether responsivity of the parathyroid gland was normal after use of (1-34)PTH daily as an investigational therapy for osteoporosis. Patients were all postmenopausal osteoporotic women treated with estrogen and enrolled in a 3-yr trial of (1-34)PTH by daily subcutaneous injection (400 IU/day) in addition to their estrogen therapy. A volunteer subgroup (n = 10) of this population was recruited for this investigation. All patients had an EDTA-provoked hypocalcemic challenge before beginning PTH treatment. The same patients had repeat EDTA-challenge tests at various times during the 3-yr PTH treatment trial. Three patients had 2 infusions while on PTH treatment (interim and at the end of 3 yr). Ionized calcium declined identically before and during PTH treatment in response to the EDTA stimulus. PTH(1-84) responses were identical before and during PTH therapy. Furthermore, there were no differences in 1,25(OH)2D elevation or in phosphorus reduction over the course of the EDTA infusion during daily PTH treatment. Osteocalcin levels were higher during PTH treatment, as expected, but responsivity to acute endogenous PTH elevations was the same after PTH treatment. We conclude that 1-34PTH therapy, at 400 IU/day for up to 3 yr, does not suppress parathyroid responsivity and should therefore (at least within this period of treatment) have no permanent adverse effect on the ability of the body to maintain calcium homeostasis. Additionally, there is no difference in target organ responsivity to acute endogenous elevations of PTH after exogenous PTH therapy.

Adult↗

Fracture history and bone loss in patients with MS.

OBJECTIVES: We have previously shown that MS patients have significantly reduced bone mass and a high prevalence of abnormal vitamin D status. The object of this study was to characterize the frequency of adulthood fractures in MS patients, prospectively determine rates of bone loss in MS, and determine whether vitamin D status is a predictor of bone loss. METHODS: MS patients (36 women, 18 men) were compared with age- and gender-matched healthy controls (35 women, 14 men). Bone mass was performed by dual x-ray absorptiometry at baseline and at 12-month intervals over 2 years. RESULTS: Fractures in the absence of major trauma had occurred in 2% of controls and 22% of MS patients (p < 0.002). Over the 2 years of prospective follow-up, both women and men with MS lost substantially more bone in the femoral neck than did controls (3% and 6% per year in pre- and postmenopausal women with MS versus 0.5% and 0.8% per year in controls; 7.3% per year in men with MS versus 1.6% per year in controls). Bone loss in the spine was also greater in women with MS than in controls (1.6 to 3.5% per year loss in MS patients versus no change in controls). Duration of steroid treatment beyond 5 months and ambulatory status were both predictors of bone loss. Bone loss in the spine occurred faster in MS patients with low (<20 ng/mL) 25-hydroxyvitamin D levels (1.9% per year, p < 0.04), whereas in those with normal 25-hydroxyvitamin D levels, bone loss was insignificant. At the femoral neck, bone loss was substantial in all patients, but was somewhat faster in the group with low levels of 25-hydroxyvitamin D (5.6% per year, p < 0.0001) compared with the group with high levels of 25-hydroxyvitamin D (4.3% per year, p = 0.03). CONCLUSIONS: MS patients have more frequent fractures and lose bone mass more rapidly than do their healthy age- and gender-matched peers, in part related to insufficient vitamin D. Vitamin D repletion in MS patients who are deficient might reduce, to some extent, the rate of bone loss and decrease osteoporosis-related fractures.

Adult↗

Human osteoclast formation and activity in vitro: effects of alendronate.

Recent advances in technique have made it possible to study human osteoclast (OC) formation and activity in vitro. The object of the present study was to determine the effects of alendronate (ALN) on human OCs generated from precursors obtained from standard peripheral blood samples. Peripheral blood mononuclear cells from 14 postmenopausal women were cocultured with ST2 stromal cells on bone slices in the presence of 10(-7) M 1,25-dihydroxyvitamin D3, 10(-8) M dexamethasone, and 25 ng/ml human macrophage colony-stimulating factor. After 21 days, the cultures contained numerous OCs, which were characterized by multinuclearity, the presence of tartrate-resistant acid phosphatase, calcitonin and vitronectin receptors, and the ability to resorb substantial amounts of bone, which was inhibited by calcitonin. The percentage area of bone resorbed per slice was highly correlated (r = 0.89, p < 0.001) with the concentration of Type I collagen cross-linked C-telopeptides (CTx) released into the culture medium. When added to the medium, ALN inhibited bone resorption at concentrations < or =10(-7) M. At 10(-7) M, inhibition was achieved primarily by a reduction in OC activity without a marked effect on OC number. At the highest concentration studied (10(-5) M), both OC number and resorption were profoundly decreased. Overnight preincubation of bone slices in ALN, without further exposure to ALN, resulted in an inhibition of resorption that was similar to that seen when ALN was present in the medium throughout the entire culture period. We conclude that, except at very high concentrations, the predominant mechanism of action of ALN is to inhibit the activity of differentiated human OCs with little or no effect on recruitment. Interaction between the OC and ALN on the bone surface is an important component of the inhibitory mechanism. Measurement of CTx in tissue culture medium is a convenient method for assessment of bone resorption in human OC cultures and offers a number of advantages over morphometric analysis of the bone slice.

Aged↗

Alendronate does not block the anabolic effect of PTH in postmenopausal osteoporotic women.

In rodent osteoporosis models, anabolic activity of parathyroid hormone (PTH) is preserved in the presence of antiresorptive agents. Anabolic activity is also preserved when PTH is administered to estrogenized postmenopausal women. In contrast, in the ewe treated with tiludronate, PTH-induced stimulation of bone turnover did not occur. To determine whether PTH in combination with alendronate could be a viable treatment for osteoporosis, we performed a short-term study of postmenopausal women with osteoporosis (n = 10) already on alendronate 10 mg/day to determine whether PTH could increase bone formation assessed biochemically. Patients continued alendronate alone (n = 5) or continued alendronate with 400 IU/day subcutaneous human PTH (1-34) added for 6 weeks. Subjects receiving PTH had serum and urine sampling weekly during PTH treatment and for 5 weeks thereafter. Sampling was performed approximately biweekly for subjects who had been on alendronate alone for 11 weeks. Samples were analyzed for osteocalcin (OC), propeptide of type I procollagen (PICP), bone-specific alkaline phosphatase (BSAP), cross-linked urinary N-telopeptide (NTX), and free urinary pyridinoline (PYD). Markers of bone formation increased within 3 weeks in the PTH plus alendronate group, with mean peak levels at 5-7 weeks: OC 49%, p < 0.01; PICP 61%, p < 0.01; and BSAP 24%, p = 0.12. Levels returned to baseline after discontinuing PTH, with PICP declining the most rapidly. There were no significant changes at any time in the alendronate alone group. There were no increments in either urinary NTX or PYD in either treatment group throughout the observation period. The bone turnover marker changes seen with PTH plus alendronate were similar to those seen with PTH plus hormone replacement. These data suggest that: PTH can stimulate bone formation, evidenced by elevations of bone formation markers, even in the presence of a potent bisphosphonate; in the presence of alendronate, PTH-stimulated bone formation precedes stimulation of bone resorption, suggesting that PTH stimulates bone formation de novo; and the combination of PTH and alendronate may be a viable treatment option for postmenopausal women with osteoporosis.

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Randomised controlled study of effect of parathyroid hormone on vertebral-bone mass and fracture incidence among postmenopausal women on oestrogen with osteoporosis.

BACKGROUND: Small increases in bone mass are commonly seen with existing treatments for osteoporosis, which reduce bone remodelling and primarily prevent bone loss. Since these drugs reduce but do not eliminate risk of fractures, an anabolic agent that would increase bone mass and potentially cure the underlying skeletal problem is needed. METHODS: We did a 3-year randomised controlled trial to find out the effects of 1-34 human parathyroid hormone (hPTH [1-34], 400 U/25 micrograms daily subcutaneously) in postmenopausal women with osteoporosis taking hormone-replacement therapy (n = 17). The controls were women taking hormone-replacement therapy only (n = 17). The primary outcome was bone-mineral density of the lumbar vertebrae, with bone-mineral density at other sites and vertebral fractures as secondary endpoints. FINDINGS: Patients taking hormone-replacement therapy and PTH (1-34) had continuous increase in vertebral bone-mineral density during the 3 years, whereas there was no significant change in the control group. The total increase in vertebral bone-mineral density was 13.0% (p < 0.001); 2.7% at the hip (p = 0.05); and 8.0% in total-body bone mineral (p = 0.002). No loss of bone mass was found at any skeletal site. Increased bone mass was associated with a reduction in the rate of vertebral fractures, which was significant when fractures were taken as a 15% reduction in vertebral height (p = 0.04). During the first 6 months of treatment, serum osteocalcin concentration, which reflects bone formation, increased by more than 55%, whereas excretion of crosslinked n-telopeptide, which reflects bone resorption, increased by only 20%, which suggests some uncoupling of bone formation and resorption. By 6 months, there were similar increases in both markers, which gradually returned towards baseline as the study progressed. Vertebral bone-mineral density increased most during the first year of PTH treatment. INTERPRETATION: We found that PTH has a pronouned anabolic effect on the central skeleton in patients on hormone-replacement therapy. PTH also increases total-body bone mineral, with no detrimental effects at any skeletal site. The increased vertebral mass was associated with a reduced rate of vertebral fracture, despite increased bone turnover. Bone-mass changes may be consistent with a reduction in all osteoporotic fractures. If confirmed in larger studies, these data have important implications for the treatment of postmenopausal osteoporosis.

Absorptiometry, Photon↗

Reduced bone mass and fat-free mass in women with multiple sclerosis: effects of ambulatory status and glucocorticoid Use.

Multiple sclerosis (MS) is associated with reduced bone mass and vitamin D deficiency. The underlying pathophysiology of the bone disease is uncertain, however, acute and long-term glucocorticoid use, progressive immobilization, vitamin D deficiency, and possibly skeletal muscle atrophy are likely to be determinants. The aims of this study were to determine (a) whether multiple sclerosis is associated with reduced fat-free mass and (b) whether in patients with multiple sclerosis, ambulation ability or glucocorticoid use is associated with bone mass and/or fat-free mass. Seventy-one female patients with MS were compared with 71 healthy, age-matched female controls. Total body bone mineral content (TBBMC, kg), fat mass (FM, kg), and fat-free mass (FFM, kg) were measured using dual X-ray absorptiometry. Disability status was graded according to the Kurtzke Expanded Disability Status Scale (EDSS) as ambulatory, with or without aide (EDSS score of 0 to 6.5), or predominantly wheelchair bound (EDSS score > 6.5). The patients with MS, when compared to age-comparable controls, had deficits in TBBMC ( approximately 8%, -0.3 +/- 0.1 SD, P < 0.04) and FFM ( approximately 5%, -0.3 +/- 0.1 SD, P < 0.01). Both TBBMC and FFM were negatively associated with EDSS score (r = 0.33, P < 0.01, and r = 0.41, P < 0.01, respectively). Patients with MS who were nonambulatory had even greater deficits in TBBMC and FFM as compared with age-matched controls (-0.6 +/- 0.1 SD, P < 0.01, and -0.6 +/- 0. 1 SD, P < 0.01, respectively). By contrast, as compared with age-comparable controls, ambulatory patients with MS had no deficits in bone mass or soft tissue mass. When compared with ambulatory patients with MS, nonambulatory patients with MS had deficits in TBBMC and FFM (P < 0.01 and P < 0.01, respectively). The difference in TBBMC was largely caused by the difference in fat-free mass, whereas the difference in FFM was largely caused by the difference in glucocorticoid use based on analysis of covariance. We conclude that in patients with multiple sclerosis, physical disuse is the main determinant for the reduction in bone mass. Glucocorticoid treatment is the major determinant of the reduction in fat-free mass and thus also contributes to the reduction in bone mass.

Adipose Tissue↗

Histomorphometric assessment of bone mass, structure, and remodeling: a comparison between healthy black and white premenopausal women.

While noninvasive studies of bone mass and turnover in blacks and whites abound, histologic evaluations are very rare. We have performed a comparative bone histomorphometric study of iliac biopsies from 55 healthy, premenopausal women including 21 blacks (mean age 33.4 + 1.2 years) and 34 whites (mean age 32.5 + 0.8 years) of comparable age, weight, body composition, education, and lifestyle. Biochemical indices of mineral metabolism: parathyroid hormone, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, serum ionized calcium, serum phosphorus, and urinary calcium/creatinine were measured in the fasting state. Blacks had lower 25-hydroxyvitamin D (315 +/- 3.36 vs. 63.21 +/- 3.79 nmol/l, p = 0.0001). Histomorphometric indices of bone volume, structure, and connectivity were not different between groups. The following indices of bone remodeling were also similar in both groups: eroded perimeter, osteoid width, mineralizing perimeter, tissue-based bone formation rate, osteoid maturation time, active formation period, and activation frequency. However, osteoid perimeter (black [B] = 15.85 +/- 1.30 vs. white [W] = 9.49 +/- 0.70%, p = 0.0002), osteoid area (B = 2.55 +/- 0.32 vs. W = 1.39 +/- 0.12%, p = 0.003), single-labeled perimeter (B = 5.46 +/- 0.54 vs. W = 4.04 +/- 0.33%, p = 0.03), mineralization lag time (B = 38.18 +/- 4.04 vs. W = 21.83 +/- 1.60 days, p < 0.009), and total formation period (B = 148.15 +/- 19.70 vs. W = 84.04 +/- 7.62 days, p = 0.0056) were higher in blacks than in whites. The quiescent perimeter (B = 76.91 +/- 1.40 vs. W = 84.25 +/- 0.91%, p = 0.0001), mineral apposition rate (B = 0.70 +/- 0.02 vs. W = 0.75 +/- 0.02 micron/day, p = 0.066), mineralizing osteoid perimeter (B = 0.49 +/- 0.04 vs. W = 0.75 +/- 0.04%, p = 0.0001) and adjusted apposition rate (B = 0.35 +/- 0.04 vs. W = 0.58 +/- 0.04 micron3/micron2/day, p = 0.0001) were all lower in blacks than in whites. These results indicate that there are no differences in bone volume, microstructure, or turnover between black and white premenopausal women. However, there are significant differences in the mechanism of bone formation between the two groups, with a lower rate of mineralized matrix apposition within each remodeling unit and a longer total formation period in blacks than in whites. The differences appear to the result of more frequent and/or longer inactive periods in the life span of the bone formation units in blacks. These differences may allow a greater overall deposition of bone mineral in black women and therefore help explain a higher bone mass and perhaps better bone quality in black than white women.

Adult↗

Bone density change and biochemical indices of skeletal turnover.

Although biochemical markers of skeletal turnover cannot replace bone density scanning for the diagnosis of osteoporosis, it is thought that they may help add to prediction of fracture risk and help determine adequacy of osteoporosis therapy. Nevertheless, whether biochemical markers in the serum or urine can predict individual rates of bone loss in the spine or hip region is unknown. We studied a heterogeneous group of women (n = 81) who were premenopausal, untreated postmenopausal, and estrogen-treated postmenopausal with baseline determination of body mass index (BMI), calcium intake, biochemical measurements, and serial bone densitometry over 3 years. Serum assays included bone Gla protein (BGP), total and bone-specific alkaline phosphatase (AP, BSAP), carboxyterminal propeptide of type I procollagen (PICP), carboxyterminal telopeptide of type I collagen (ICTP) and tartrate-resistant acid phosphatase (TRAP). Urine assays included hydroxyproline (OHP), calcium, total pyridinoline, and total deoxypyridinoline. Individual biochemical markers and calcium intake were modestly correlated with bone density changes but were inconsistent regarding the spine versus the hip. All of the formation variables were significantly correlated to spine density change (r = -0.24 to -0.49) whereas the only resorption variable that correlated was urine OHp/Cr (r = -0.31). The only formation variable that correlated with hip density change was serum PICP whereas all of the resorption variables except serum TRAP were correlated (r = -0.23 to -0.35). "High turnover" individuals were defined at those with levels of biochemical variables at least 1 SD above the mean young normal for each variable. Higher bone loss rates were seen in this group for several of the turnover markers compared with bone loss rates in all other individuals. However, the sensitivity of this "high turnover" status for identifying high bone losers did not exceed 60% for any of the variables. In untreated postmenopausal women, a model using urine OHp, serum ICTP, serum BSAP, and calcium intake was able to predict 42% of the variance of change in BMD of the lumbar spine. A model using BMI, serum ICTP, and serum BGP could predict 32% of the variance of change in BMD of the femoral neck. No combination of markers could predict variance in bone density change at either site in estrogenized women (premenopausal and estrogen-treated postmenopausal). We conclude that measuring individual serum and urine markers of bone turnover cannot accurately predict bone loss rates in the spine and hip; however, combinations of demographic and biochemical variables could predict some of the variance in untreated postmenopausal women. Biochemical markers cannot replace serial bone densitometry for accurate determination of change in bone mass at the most clinically relevant sites.

Adult↗

Oral 1,25-dihydroxyvitamin D administration in osteoporotic women: effects of estrogen therapy.

Estrogen has been shown to modify calcium and skeletal homeostasis. In this study, we tested the ability of estrogen to influence the effects of short-term 1,25(OH)2D administration on biochemical indices of bone formation and resorption in a cross-sectional analysis of untreated (n = 10) and estrogen-treated (n = 14) osteoporotic women. Patients were given oral 1,25(OH)2D (Rocaltrol) 0.5 microgram twice a day for 5 days. Serum and urine were sampled at baseline and then 1 h after the first daily Rocaltrol dose for the 5 days of the study. 1,25(OH)2D levels rose similarly in both groups with plateaus reached by the third day of the investigation. Serum PTH levels decreased by the first sampling period (1 h after first Rocaltrol dose; p < 0.008 both groups) and continued to fall gradually in both groups. There were no changes in serum calcium but serum phosphorus rose by the second day (p < 0.05 both groups) and remained elevated throughout the remainder of the protocol. Serum bone Gla protein increased approximately 40% (p < 0.05) with no group differences. In contrast, total alkaline phosphatase and carboxy-terminal propeptide of type I collagen did not increase in either group. Furthermore, there were no significant increments in any bone resorption indicators, including serum tartrate-resistant acid phosphatase and cross-linked carboxy-terminal telopeptide of type I collagen, as well as urine hydroxyproline and pyridinoline. Serum IGF-1 levels also remained unchanged in both groups. We conclude that oral 1,25(OH)2D administration decreased 1-84PTH levels, probably due to a suppression of parathyroid production, and did not stimulate bone resorption.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗

Bone structure in postmenopausal hyperparathyroid, osteoporotic, and normal women.

The purpose of this study was to test the hypothesis that patients with mild primary hyperparathyroidism are protected against postmenopausal (PM) loss of cancellous bone architecture. To achieve this, we compared bone structure and turnover in iliac bone biopsies from three groups: 16 women with mild primary hyperparathyroidism (PHPT; 58.2 +/- 2.2 years, 11.5 +/- 1.7 years PM), 17 women with untreated primary osteoporosis (OP; 65.1 +/- 2.0 years, 17.2 +/- 2.3 years PM), and 31 healthy women (N; 59.8 +/- 1.4 years, 13.4 +/- 1.5 years PM). The bone formation rate was significantly higher in PHPT than in either OP or N, and not different between OP and N. Cancellous bone volume, total strut length, and indices of connectivity (node number, node to node strut length, and node to terminus ratio) were significantly lower in OP than in either PHPT or N but were the same or higher in PHPT than in N. Indices of disconnectivity were significantly lower in PHPT than in N, whereas they were the same or higher in OP than N. The data were also analyzed in subgroups matched by years PM with no changes in the results. These findings indicate that osteoporotic patients with normal bone turnover have low bone volume and microarchitectural deterioration, while patients with mild PHPT have normal bone volume and normal or greater trabecular connectivity despite higher bone turnover. These findings suggest that mild PHPT protects against the loss of cancellous bone structure that normally follows menopause.

Bone and Bones↗

Postmenopausal osteoporosis: patient choices and outcomes.

OBJECTIVE: Only two medications, estrogen and injectable salmon calcitonin, are currently approved by the FDA for the treatment of osteoporosis. Oral etidronate has been investigated but not approved for osteoporosis therapy. We compared the three available anti-resorptive medications in untreated osteoporotic women. DESIGN: A nonrandomized, open label trial. After baseline biochemistry and bone mineral density (BMD) determinations, subjects self-selected therapy based on descriptions of the three drugs which were similar for all patients. Bone densitometry of the lumbar spine, femoral neck and distal and proximal forearm sites was repeated every 6 months. RESULTS: Twenty-one patients chose estrogen, 20 chose etidronate and 11 chose calcitonin. Fear of breast cancer was the most common reason given for not choosing estrogen therapy. Mean age was slightly lower and spine and hip bone densities slightly higher in the estrogen group compared with both the etidronate and calcitonin groups. In the lumbar spine, all three agents resulted in similar small increments (mean increments 1.2-4.4% at 2 years). In the estrogen group, there was no change in femoral neck density while there were significant losses in both calcitonin and etidronate groups (3.1-4.9%). In the forearm, there was either no change (distal site) or an increment (proximal site) in the estrogen group, while both etidronate and calcitonin groups demonstrated a mean loss at both sites over the 2-year observation period. CONCLUSIONS: These preliminary results suggest that all three agents appear equally effective at maintaining or increasing BMD of the lumbar spine, while estrogen appeared more effective at maintaining or increasing BMD of the appendicular skeleton. This study underscores the need for an alternative to estrogen therapy which is equally effective and can be given orally for those in whom estrogen is either contraindicated or undesirable.

Aged↗

Milk and bones.

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Animals↗