Increment In Bone Mineral Density Research Articles

Effect of GnRH Analogs Leuprolide-Acetate and Triptorelin on Bone Mineral Density in Girls with Central Precocious Puberty

Purpose: The objective of this study was to evaluate the effect of gonadotropin releasing hormone analog (GnRHa) treatment on bone mineral density (BMD) in girls with central precocious puberty (CPP). Further we investigated the differences in the effect on BMD by using the GnRHa leuprolide-acetate and triptorelin. Methods: Sixty-one females with CPP were enrolled in the study, the lumbar spine BMD was measured by dual energy x-ray absorptiometry before treatment, after one year (n = 61) and after two years (n = 24) of treatment. Lumbar spine BMD standard deviation scores (SDS) were compared according to chronological age (CA) and bone age (BA) for the whole group, as well as for the group A, treated with leuprolide-acetate (n = 40), and the group B, treated with triptorelin (n = 21). Results: All subjects showed significant increment in BMD during treatment (P ˂ 0.05). Lumbar spine BMD SDS for CA and BA showed no significant changes before and during treatment. Group A and group B, within each group, showed no significant changes in lumbar spine BMD SDS for CA and BA during treatment. Conclusion: Our study suggests that lumbar spine BMD was not impaired in girls treated with GnRHa for CPP and both leuprolide-acetate and triptorelin showed comparable effects on lumbar spine BMD during treatment. (J Korean Soc Pediatr Endocrinol 2011;16:106-111)

Bone Mineral Density Changes In Patients with Paraproteinemia After Treatment with Bortezomib

AbstractAbstract 4989 Background:Bone disease is present at diagnosis in almost all patients with multiple myeloma (MM) and can impact substantially on patient morbidity and quality of life. Decreased bone mineral density is also observed not only in MM but also in patients with monoclonal gammopathy of undetermined significance (MGUS). The pathogenesis of bone disease in MM is complex. The activity of proteasome inhibitor bortezomib has been linked to increased bone formation and osteoblastic activation. Evidence from the available clinical data indicates that bortezomib has a positive impact on bone health in MM and demonstrates a bone anabolic effect. Methods:We analyzed retrospectively 53 patients with MM and 16 with MGUS who have completed bone density at least at diagnosis. 21 patients have completed two bone density (3 MGUS and 18 MM). The bone density was obtained in all patients at baseline and in 16 patients repeated after bortezomib treatement with a median time of bortezomib exposure of 6 months. We analyzed T-score values at lumbar spine and at femoral neck. Results:With a median age of 66 years, 41 male and 28 female were analyzed. At baseline the mean lumbar spine T-score of all subjects and of 16 MM treated with bortezomib was -0.50 and -0.76 respectively. At baseline the mean femoral neck T-score for all subjects and for 16 MM treated with Bortezomib was -1.56 and -1.31 respectively. The baseline mean lumbar spine T-score for MGUS and MM was -0.71 and -0.43 respectively. The baseline mean femoral neck T-score of MGUS and MM was -1.61 and -1.54 respectively. In the group of 16 patients treated with Bortezomib we observed from baseline a change in lumbar bone mineral density T-score of 0.36 and at femoral neck bone density T-score of 0.25. Conclusion:These data show that patients treated with proteasome inhibitor showed moderate increment in bone mineral density at lumbar spine and at femoral neck. [Display omitted] [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Bone Mineral Density in Children Treated With Daily or Periodical Inhaled Budesonide: The Helsinki Early Intervention Childhood Asthma Study

In a double-blind, randomized study, 136 children, 5-10-y-old, with newly detected persistent asthma received budesonide (BUD) 400 microg twice daily for 1 mo and thereafter 200 microg twice daily for 5 mo. Thereafter, 50 children were treated with BUD 100 microg twice daily, whereas 44 children used BUD as needed for 1 y; an additional 42 children received disodium cromoglycate (DSCG). Asthma exacerbations were treated with BUD for 2 wk in a dose of 400 microg twice daily in all groups. In this secondary analysis, bone mineral density (BMD) of the lumbar vertebrae was measured before and after the 18-mo treatment. Compared with DSCG, regular BUD treatment resulted in a significantly smaller increase in BMD (0.023 versus 0.034 g/cm; p = 0.023) and height (7.75 versus 8.80 cm; p = 0.001). Periodic treatment did not affect BMD. No intergroup differences were observed when BMD data were adjusted for changes in height. Daily BUD treatment in prepubertal children may slow down the increment in BMD and standing height. This was not observed in children receiving BUD periodically after the initial regular BUD treatment. The correlation between height and BMD suggests that following children's height might afford an estimation of inhaled corticosteroid effects on bone.

Effects of Teriparatide in Postmenopausal Women with Osteoporosis on Prior Alendronate or Raloxifene: Differences between Stopping and Continuing the Antiresorptive Agent

The aim of the study was to assess adding vs. switching to teriparatide 20 microg/d in patients on alendronate or raloxifene. We conducted a randomized, open-label trial. Postmenopausal women with osteoporosis on alendronate or raloxifene for at least 18 months added teriparatide (Add groups) or switched to teriparatide (Switch groups) for 18 months. We measured bone turnover markers (BTM) and bone mineral density (BMD). In the alendronate stratum, increases in BTM were smaller in the Add vs. Switch group [6-month PINP (64 vs. 401%); bone ALP (15 vs. 71%); betaCTX (27 vs. 250%); all P < 0.001]. However, at 6 months, total hip BMD increased more in the Add vs. Switch group (1.4 vs. -0.8%; P = 0.002). In the Add vs. Switch group, 18-month BMD increments were higher in lumbar spine (8.4 vs. 4.8%; P = 0.003) and total hip (3.2 vs. 0.9%; P = 0.02), but not in femoral neck (2.7 vs. 2.3%; P = 0.75). In the raloxifene stratum, increases in BTM were also smaller in the Add vs. Switch group [6-month PINP (131 vs. 259%; P < 0.001), bone ALP (31 vs. 44%; P = 0.035), and betaCTX (67 vs. 144%; P = 0.001)]. At 6 months, total hip BMD increase was greater in the Add vs. Switch group (1.8 vs. 0.5%; P = 0.028). At 18 months, increases in lumbar spine (9.2 vs. 8.1%), total hip (2.8 vs. 1.8%), and femoral neck (3.8 vs. 2.2%) were not significantly different between groups. In women with osteoporosis treated with antiresorptives, greater bone turnover increases were achieved by switching to teriparatide, whereas greater BMD increases were achieved by adding teriparatide.

Hormones and osteoporosis update. Adrenal androgen and bone

DHEA is the major source for estrogen biosynthesis in postmenopausal women, since DHEA is converted to estrogen by aromatase in peripheral tissues. It has been suggested by animal models that a direct action of DHEA on bone tissue exists in addition to a biological action by estradiol converted from DHEA. Several RCTs (randomized, double-blinded, controlled trials) indicated that administration of daily 50 mg of DHEA increased bone mineral density (BMD) of lumbar spine or femoral neck. Increment of BMD was significant but small. The effect of DHEA on BMD is considered to be attributable to that of estradiol converted from DHEA, judging from analysis of serum steroid hormone concentrations.

Associação entre a perda de peso, a massa óssea, a composição corporal e o consumo alimentar de adolescentes obesos pós-púberes

To verify the effects of weight loss on bone mass of obese adolescents submitted to a nutritional intervention based on a hypocaloric diet and nutritional advice over a nine-month-period. Anthropometry, body composition, BMD and dietary intake were evaluated. Fifty-five adolescents, 78.2% females, within an average age of 16.6 (1.4) years old participated in the study. Sixteen participants who completed the study did not lose weight. The group that adhered to the nutritional intervention had a mean weight loss of 6.2 (4.6)% baseline. There was a significant increase in total BMD and bone mineral content (BMC) in those adolescents who did not lose weight, while increased BMC and bone area were verified in participants who lost weight, mainly when associated with body composition alterations while changing weight. The increment in bone mineral density, even throughout weight loss, has showed no negative effect on bone mass and has also emphasized the importance of nutritional improvement in total bone mass during adolescence.

Stimulation of intramembranous bone repair in rats by ghrelin

Researchers in our laboratory have previously shown that ghrelin, a gastric peptide hormone, may regulate mesenchymal cell differentiation into adipocytes and myocytes. Here we show that ghrelin promotes osteogenesis of intramembranous bone and improves the repair of calvarial bone defects in rats. Rats with a 9 mm full-thickness calvarial bone defect received either Bio-Oss (control group) or Bio-Oss mixed with 20 mug ghrelin (treatment group), followed by local administration of saline or ghrelin (10 microg), respectively, on days 5, 10 and 15. After 6 and 12 weeks, new bone formation was assessed. Animals treated with ghrelin showed a significant increase in new bone formation as demonstrated by an increment in bone mineral density and fluorescence labelling of tetracycline relative to the control group. At 6 weeks, bone mineral density increased from 54 +/- 7 (control group) to 78 +/- 9 mg cm(-2) in the treatment group, while the tetracycline fluorescence labelling increased by 61 +/- 15%. A similar increment was observed at 12 weeks. Quantitative reverse transcriptase-polymerase chain reaction showed that expression of alkaline phosphatase (ALP), osteocalcin and collagen type I was elevated. Relative to the control animals, mRNAs for ALP, osteocalcin and collagen type I increased 2.4 +/- 0.4-, 4.7 +/- 1.9- and 4.0 +/- 1.7-fold, respectively, in animals treated with ghrelin for 6 weeks (P < 0.05). At 12 weeks, mRNA levels of ALP, osteocalcin and collagen type I showed a decline relative to levels at 6 weeks but still remained significantly higher than in the control group, with fold changes of 2.4 +/- 0.8, 2.4 +/- 1.2 and 2.1 +/- 0.7, respectively (P < 0.05). This study demonstrated that ghrelin stimulates intramembranous osteogenesis.

Effects of physical training on bone mineral density in fertile women with idiopathic osteoporosis

The aim of this study was to investigate whether moderate physical training can improve the bone mineral density (BMD) in women with idiopathic osteoporosis. Ten pre-menopausal women aged 24-44 years diagnosed with idiopathic osteoporosis were included in the study. The physical training program consisted of three fast 30-min walks plus one or two sessions of 1-h training per week during 1 year at a training centre separate from the hospital. All patients were given supplements of vitamin D and calcium. Bone mineral density was measured in the femoral neck area and the lumbar spine by dual energy X-ray absorptiometry. The measurements were performed at baseline and after 12 months of training and compared with the measurements at the time of diagnosis, 1-3 years before the study. Eight women fulfilled the 12-month training period, and their mean (SD) BMD at start was 0.88 (0.08) g/cm(2) in the spine and 0.76 (0.13) g/cm(2) in the femoral neck. The mean spine BMD increase was 0.031 g/cm(2) (3.5%) after 1 year of training, which was significant (Wilcoxon's non-parametric test, p = 0.018). The mean increment in BMD in the femoral neck was insignificant, 0.007 g/cm(2) (0.9%) after the intervention (p = 0.74). However, the bone loss during the 1- to 3-year period from diagnosis to study start was, on average, 0.045 g/cm(2) or 5.0% in the femoral neck (p = 0.042), thus indicating a positive indirect effect of the intervention. There is no evidence-based therapy for women with idiopathic osteoporosis. It is therefore of importance to elucidate the impact of moderate physical activity in this group of patients. A 1-year training program was sufficient to induce a small but significant change in the spine BMD.

Body composition and bone density in Canadian White and Aboriginal women: The First Nations Bone Health Study

Ethnic variation in soft tissue composition may contribute to observed ethnic differences in bone mineral density (BMD). This analysis was performed to determine whether ethnic differences in body composition affect differences in BMD between Canadian White and Aboriginal women. An age-stratified population-based sample of 206 Aboriginal women and 177 White women underwent multisite bone density measurements and total body soft tissue composition analysis. In univariate analyses, each kg of additional lean mass was associated with a greater increase in BMD than an equal amount of fat mass ( p < .01). When models simultaneously evaluated both soft tissue measurements, lean mass (but not fat mass) was positively correlated with BMD at all measurement sites ( p < .001). Aboriginal women had significantly lower weight-adjusted BMD than White women for two sites (calcaneus, p = .019; total body, p = .026) and lower BMI-adjusted for BMD three sites (calcaneus, p = .0076; distal forearm, p = .047; total body, p = .022). The ratio of lean mass to fat mass was lower in Aboriginal than White women ( p < .001). When BMD was adjusted for body composition variables no significant difference was seen between Aboriginal and White women. Apparent ethnic differences in weight- and BMI-adjusted BMD between Canadian White and Aboriginal women were explained by a lower ratio of lean mass to fat mass in Aboriginal women, combined with a smaller increment in BMD from fat mass versus lean mass in both populations.

Effect of testosterone therapy on lumbar spine and hip mineral density in elderly men

Objective. The aim of the present study was to analyse the effect of testosterone therapy on bone mineral density in healthy elderly men who had low levels of total testosterone.Design. Randomized, double-blind, placebo-controlled study.Participants. Forty-eight men over 60 years old with decreased testosterone levels (≤320 ng/dL) comprised the study. Twenty-five out of 48 received intramuscular injections of testosterone enanthate every three weeks during 12 months; the remaining 23 participants formed the control group. All participants had measurements of bone mineral density (BMD) in both lumbar spine and hip before and at the end of the study as well as testosterone and 17-β estradiol levels.Results: Testosterone treated group exhibited a significant (p < 0.05) increment (from 1.198 ± 0.153 to 1.240 ± 0.141 g/cm2) in lumbar BMD in parallel with a significant (p < 0.001) increment (from 301 ± 32 to 471 ± 107 ng/dL) in testosterone concentrations, whereas no significant change occurred in femoral neck BMD.Conclusions. Testosterone therapy elicited a positive effect only in lumbar BMD in elderly men with diminished testosterone serum levels.

A 12-Month Treatment With Tenofovir Does Not Impair Bone Mineral Accrual in HIV-Infected Children

Short-term use of tenofovir (TDF) has been associated with bone mineral loss in adults and children. To assess whether the substitution of stavudine with TDF would result in decreased bone mineral content (BMC) and bone mineral density (BMD) accrual in HIV-infected children. The lumbar spine and whole-body BMC and BMD were measured by dual-energy x-ray absorptiometry in 16 HIV-infected children (age range: 6.4-17.9 years) on stable highly active antiretroviral therapy. Bone measurements were obtained 12 months before the switch, at baseline, and 12 months after switching to TDF. Expected changes in bone measurements were calculated from cross-sectional data obtained from 166 healthy children. The BMC and BMD increments observed before switching therapy did not differ from expected increments. Similarly, the changes detected during treatment with TDF did not differ significantly from those calculated in healthy controls. Substitution to a TDF-containing antiretroviral regimen does not seem to impair bone mineral accrual in children showing a good immunologic response to antiretroviral treatment.

Effect of Vitamin D Replacement on Musculoskeletal Parameters in School Children: A Randomized Controlled Trial

Despite the high prevalence of hypovitaminosis D in children and adolescents worldwide, the impact of vitamin D deficiency on skeletal health is unclear. One hundred seventy-nine girls, ages 10-17 yr, were randomly assigned to receive weekly oral vitamin D doses of 1,400 IU (equivalent to 200 IU/d) or 14,000 IU (equivalent to 2,000 IU/d) in a double-blind, placebo-controlled, 1-yr protocol. Areal bone mineral density (BMD) and bone mineral content (BMC) at the lumbar spine, hip, forearm, total body, and body composition were measured at baseline and 1 yr. Serum calcium, phosphorus, alkaline phosphatase, and vitamin D metabolites were measured during the study. In the overall group of girls, lean mass increased significantly in both treatment groups (P < or = 0.05); bone area and total hip BMC increased in the high-dose group (P < 0.02). In premenarcheal girls, lean mass increased significantly in both treatment groups, and there were consistent trends for increments in BMD and/or BMC at several skeletal sites, reaching significance at lumbar spine BMD in the low-dose group and at the trochanter BMC in both treatment groups. There was no significant change in lean mass, BMD, or BMC in postmenarcheal girls. Vitamin D replacement had a positive impact on musculoskeletal parameters in girls, especially during the premenarcheal period.

Genistein derivatives as selective estrogen receptor modulators: Sonochemical synthesis and in vivo anti-osteoporotic action

Genistein derivatives were synthesized from genistein through a facile sonochemical approach in high yields. The bioassay was performed on ovariectomized (OVX) rats in terms of bone mineral density (BMD) and the weight of bone ash (WBA) to lead to the discovery of eight novel genistein-based selective estrogen receptor modulators. Attention to the structure–activity relationship disclosed that the newly introduced 2-hydroxyethylthio scaffolds were essential for the anti-osteoporotic activity. Moreover, the anti-osteoporotic action of genistein, deprivable by methylation, could be restored and enhanced by subsequent sulfonation. The most promising compound was 4′,5,7-tri[3-(2-hydroxyethylthio)propoxy]isoflavone, displaying 24% (or 8%) increment in BMD and 31% (or 11%) increase in WBA of the femora relative to those discerned with the OVX (or genistein) group. Acute toxicity test showed that none of the active compounds was acutely toxic.

A 1-year combined weight-bearing training program is beneficial for bone mineral density and neuromuscular function in older women

Forty-eight community living women 66-87 years old volunteered to participate in a 12-month prospective, randomized, controlled, trial. The aim was to determine if a combined weight-bearing training program twice a week would be beneficial to bone mineral density and neuromuscular function. The participants were pairwise age-matched and randomly assigned to either an exercise group (n=24) or a control group (n=24). Twenty-one subjects in the intervention group and 19 in the control group completed the study. The exercise program lasted for 50 min and consisted of a combination of strengthening, aerobic, balance and coordination exercises. The mean percentage of scheduled sessions attended for the exercise group was 67%. At the completion of the study, the intervention group showed significant increments in bone mineral density of the Ward's triangle (8.4%, P<0.01) as well as improvement in maximum walking speed (11.4%, P<0.001) and isometric grip strength (9.9%, P<0.05), as compared to the control group. The conclusion was that a combined weight-bearing training program might reduce fracture risk factors by improving bone density as well as muscle strength and walking ability. This program could be suitable for older community living women in general, and might, therefore, have important implications for fracture prevention.

Bone mass and bone metabolism in pediatric gastrointestinal disorders.

Bone mass and bone metabolism in pediatric gastrointestinal disorders.

The oxidative metabolism of estrogen modulates response to ERT/HRT in postmenopausal women

We have previously demonstrated that estrogen metabolism is one of the determinants of bone density after menopause. Increased hydroxylation to relatively nonestrogenic metabolites 2-hydroxyestrone (2OHE 1) and 2-methoxyestrone (2MeOE 1) was associated with low bone mineral density (BMD), while increased hydroxylation to the potent 16α-hydroxyestrone (16αOHE 1) and weakly estrogenic estriol (E 3) was associated with higher BMD. In this study, we tested the hypothesis that response to estrogen–hormone replacement therapy (ERT/HRT) is also related to individual differences in estrogen metabolism. Urinary estrogen metabolites were measured in 310 postmenopausal women using ESTRAMET enzyme immunoassay kit. Of these, 163 were on HRT with conjugated equine estrogen (CEE) and medroxyprogesterone acetate (MPA, Premarin™ and Provera™) or ERT with conjugated equine estrogen alone (Premarin™), and 147 women not on ERT/HRT acted as comparison. Annual rates of BMD changes were calculated on a subset of 81 women on ERT/HRT who had more than one previous BMD measured by dual-energy X-ray absorptiometry (DEXA). Controlling for age, years since menopause (YSM), body mass index (BMI), waist to hip ratio, and smoking, we found that urinary estrogen metabolite levels were significantly higher in ERT/HRT-treated women compared to those not on ERT/HRT. Furthermore, women in the higher 2 tertiles of 2OHE 1 and 2OHE 1/16áOHE 1 ratio had positive increments in BMD compared to those in the lowest tertile who lost bone while on ERT/HRT. Thus, women with estrogen metabolism favoring the 2-hydroxylation pathway respond favorably to ERT/HRT.

Longitudinal changes of bone mineral density and metabolism in antiretroviral-treated human immunodeficiency virus-infected children.

Highly active antiretroviral therapy (HAART) may be a contributory factor for a decreased bone mass and altered bone metabolism in HIV-infected children. However, the evolution of bone mineral density (BMD) and bone metabolism during HAART has not been studied yet. In the current longitudinal study we monitored the changes of BMD and bone metabolism over a period of 12 months. Thirty-two HIV-infected children (15 girls and 17 boys), aged from 6.3 to 17.7 yr, with a long duration of HAART exposure (40.0 months at baseline) were enrolled in the study. As a control group, 381 healthy volunteers of comparable age were assessed. BMD was measured at the lumbar spine and whole skeleton by dual-energy x-ray absorptiometry. Bone-specific alkaline phosphatase (BALP, as bone formation index) and N-terminal telopeptide of type I collagen (as bone resorption index) were measured in serum and urine, respectively. BMD values at baseline were significantly lower at all skeletal sites than those of control subjects. The annual increment of spine BMD was comparable to normal, whereas that of the whole skeleton was significantly lower (P < 0.04). BALP and N-terminal telopeptide of type I collagen concentrations were significantly higher compared with controls at baseline and at follow-up. BALP annual changes of HIV patients were significantly different from normal. Our data confirm the presence of low BMD and bone metabolism derangement in HIV-infected children treated with HAART. The role of possible therapeutic approach to restore bone mass and metabolism should be assessed in pediatrics.

An investigation of the predictors of bone mineral density and response to therapy with alendronate in osteoporotic men.

Male osteoporosis is an important disease, with 25-30% of all hip fractures occurring in men. In a recent randomized, placebo-controlled study of osteoporotic males, alendronate 10 mg daily for 2 yr led to significant increments in bone mineral density (BMD), of a similar magnitude to those observed in postmenopausal women. In this study, specimens collected at intervals during the recent trial of alendronate in male osteoporosis, from 197 of the original 241 participants, were assayed for testosterone, estradiol, IGF-I, IGF binding protein 3 (IGFBP-3), bone-specific alkaline phosphatase [BSAP (serum)], and N-telopeptide of type I collagen corrected for creatinine [NTx (urine)]. Together with fracture and densitometry data from the original study, relationships were examined between BMD and serum IGF-I, IGFBP-3, testosterone, estradiol, BSAP, and urine NTx, both at baseline and during treatment with alendronate, to gain possible insights into the pathogenesis of male osteoporosis. Statistically significant (P <or= 0.05) associations were documented, at baseline, between the presence of vertebral fracture and each of serum IGF-I, serum IGFBP-3, serum free testosterone, total spine BMD, and total body BMD. No statistically significant correlations were observed between any of the baseline variables (IGF-I, IGFBP-3, estradiol, testosterone, and presence of vertebral fracture) and the BMD response to alendronate at any site. In a multivariate analysis, used to identify possible combinations of factors capable of predicting baseline BMD or response to alendronate, statistically significant (P <or= 0.01) relationships were seen, at baseline, between BMD and body mass index, age, and prior fracture. However, no statistically significant relationships were seen between any of the baseline variables (age, body mass index, testosterone, estradiol, IGF-I, IGFBP-3, and prior fracture) and change in BMD at any site. These data suggest that among men with osteoporosis it is not possible to identify patients who would be particularly good candidates for therapy with alendronate on the basis of biochemical or hormonal markers. Alendronate therapy appears to benefit osteoporotic males equally, irrespective of baseline serum testosterone, estradiol, IGF-I, or markers of bone turnover.

Response of Bone Mineral Density to Once-Weekly Administration of Risedronate

To evaluate the changes in bone mineral density (BMD) and the tolerability associated with treatment with risedronate, 30 mg once weekly. Risedronate, 30 mg, was administered once weekly before breakfast to patients with osteoporosis or osteopenia. All patients were also treated with calcium, 1,500 mg daily, and supplemental vitamin D. Patients receiving treatment with other antiresorptive agents were not excluded. BMD was assessed with dual-energy x-ray absorptiometry (DEXA) at baseline and 1 year. After a mean of 11.6 +/- 0.4 months, mean BMD had increased at the lumbar spine and total hip, respectively, by 5.7% (P<0.001) and 2.9% (P<0.001) among all patients, by 4.8% (P<0.001) and 2.2% (P<0.04) among 23 treated with risedronate alone, and by 6.7% (P<0.003) and 3.6% (P<0.004) among 21 receiving risedronate and other antiresorptive agents. Linear regression analysis of the relationship between baseline T-score and BMD increment at the lumbar spine and femoral neck showed a statistically significant negative correlation, an indication of an enhanced response to treatment in patients with lower baseline T-scores. Adverse events possibly associated with risedronate therapy were recorded in 3 of the 70 enrolled patients (dyspepsia in 2 and urticaria in 1). Of 44 patients with follow-up DEXA scans, 12 (27%) had not tolerated alendronate (10 mg daily) previously, but they tolerated once-weekly risedronate therapy without difficulty. A once-weekly 30-mg regimen of risedronate increases BMD when administered alone or with other antiresorptive agents. Few adverse events possibly associated with risedronate therapy were noted.

The Effects of Region-Specific Resistance and Aerobic Exercises on Bone Mineral Density in Premenopausal Women

Epidemiological, cross-sectional, and prospective studies strongly suggest that exercise has beneficial effects on bone mass in premenopausal women. We prospectively compared the effects of resistance or aerobic exercises on regional bone mass in premenopausal active duty military women ranging in age from 19 to 40 years. Subjects were assigned, by preference, to a resistance exercise group or an aerobic exercise group and instructed to exercise at least 30 minutes per day, three times per week, for a period of 1 year. Bone mineral density (BMD) was measured by dual photon absorptiometry at the lumbar spine and femoral neck and by single photon absorptiometry at the mid radius at baseline, 6 months, and 12 months. BMD increments during the study were statistically significant at all sites in both exercise groups. Comparisons between the groups showed that after 12 months, BMD increased similarly in the lumbar spine (2.2% resistance vs. 1.8% aerobics, p = not significant) but more in the resistance group in the femoral neck (5.0% vs. 2.7%, p < 0.001) and the mid radius (7.8% vs. 6.7%, p < 0.05). Both resistance and aerobic exercises increase regional bone mass, particularly cortical bone mass, in premenopausal women. Resistance work appears to have a slightly greater effect on cortical bone than aerobics alone. A combination of aerobics and resistance exercises, therefore, may be a useful strategy for increasing peak bone mass in premenopausal women.