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Nelson B Watts

Publications and source records attributed to Nelson B Watts.

At least 37 records · Page 2Linked to original sources
PubMed2004

A comparison of the effects of raloxifene and conjugated equine estrogen on bone and lipids in healthy postmenopausal women.

BACKGROUND: Although many studies have assessed the effects of estrogen and raloxifene hydrochloride on bone mineral density and serum lipid concentrations, there are few direct comparative data. METHODS: Randomized placebo-controlled trial for 3 years, intention-to-treat analysis. Six hundred nineteen postmenopausal women with prior hysterectomy (mean age, 53.0 years) were studied in 38 centers in Europe, North America, Australasia, and South Africa. They were randomized to 60 mg/d or 150 mg/d of raloxifene, 0.625 mg/d of conjugated equine estrogen (CEE), or placebo. Bone density of the lumbar spine and proximal femur, biochemical markers of bone turnover, and fasting serum lipid concentrations were assessed for 3 years. RESULTS: Compared with baseline, bone density in the lumbar spine progressively declined by 2.0% in the placebo group (P <.05), was stable in the 2 raloxifene groups, and increased 4.6% in the subjects receiving CEE (P <.001). Effects in both raloxifene groups were different from those observed in the CEE and placebo groups (P <.001). Bone density in the total hip showed similar results. Conjugated equine estrogen produced significantly greater depression of serum osteocalcin, bone-specific alkaline phosphatase, and urine C-telopeptide, compared with raloxifene. Each of the active treatments caused comparable depression of low-density lipoprotein cholesterol below placebo levels (P <.001 at most time points). Raloxifene did not affect high-density lipoprotein cholesterol, whereas CEE increased it by 13.4% compared with placebo at 3 years (P <.001). Triglyceride concentrations increased 24.6% in the CEE group at 3 years (P <.003), a significantly greater change than in the raloxifene groups, which were 4.9% and 8.0% above baseline (P < or =.002) but not different from placebo. Urinary incontinence was reported in 11 women receiving CEE, but in only 1 or 2 in each of the other groups (P < or =.01 compared with the other groups). Hernias occurred less frequently in those receiving 150 mg/d of raloxifene or CEE (P =.03 vs placebo). CONCLUSIONS: Raloxifene and CEE have beneficial effects on bone density and bone turnover, although effects of CEE are more marked. Raloxifene and CEE produce different patterns of lipid responses and have distinct adverse effect profiles.

Alkaline Phosphatase↗
PubMed2004

Is it ethical to use placebos in osteoporosis clinical trials?

Because there are now effective agents for treatment of osteoporosis, the question is being raised as to whether or not it is ethical to have placebo-controlled trials of new agents. It is ethical for patients who are at low risk of serious or irreversible harm to participate in placebo-controlled trials as long as they provide informed consent. Morbidity, mortality, and future fracture risk correlate with the presence of previous fractures, the number of previous fractures, whether or not the fracture is recent, and whether or not the fracture is clinically recognized. Lower-risk subjects who may be allowed to participate in placebo-controlled trials include those with low bone density but without a previous vertebral fracture, those with a single vertebral deformity that was not clinically recognized, and those with a vertebral fracture more than 2 years before. Higher-risk subjects who do not tolerate proven drugs or who have not responded to proven drugs may also participate. Even though it may be ethical for selected subjects to participate in placebo-controlled trials of new therapies for osteoporosis, steps should be taken to minimize their exposure (eg, unbalanced randomization, integration of outcomes, and powering trials to actual events rather than a projected number over 3 years), and treating patients who fracture or who fail to respond.

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PubMed2004

Is it ethical to use placebos in osteoporosis clinical trials?

Because there are now effective agents for treatment of osteoporosis, the question is being raised as to whether or not it is ethical to have placebo-controlled trials of new agents. It is ethical for patients who are at low risk of serious or irreversible harm to participate in placebo-controlled trials as long as they provide informed consent. Morbidity, mortality, and future fracture risk correlate with the presence of previous fractures, the number of previous fractures, whether or not the fracture is recent, and whether or not the fracture is clinically recognized. Lower-risk subjects who may be allowed to participate in placebo-controlled trials include those with low bone density but without a previous vertebral fracture, those with a single vertebral deformity that was not clinically recognized, and those with a vertebral fracture more than 2 years before. Higher-risk subjects who do not tolerate proven drugs or who have not responded to proven drugs may also participate. Even though it may be ethical for selected subjects to participate in placebo-controlled trials of new therapies for osteoporosis, steps should be taken to minimize their exposure (eg, unbalanced randomization, integration of outcomes, and powering trials to actual events rather than a projected number over 3 years), and treating patients who fracture or who fail to respond.

Bone Density↗
PubMed2004

Efficacy of risedronate on clinical vertebral fractures within six months.

OBJECTIVE: Postmenopausal osteoporotic women with pre-existing or new incident vertebral fractures are at high risk for future fracture, so prompt treatment is warranted. Risedronate has been shown to reduce the incidence of radiographically-defined vertebral fractures by approximately two-thirds within 1 year. RESEARCH DESIGN: This study examined the effects of risedronate treatment on the time course of the reduction in the risk of clinical vertebral fractures (i.e., symptomatic fractures), on the risk of moderate-to-severe radiographic vertebral fractures, and on height. RESULTS: In 2442 postmenopausal women with prevalent vertebral fractures from the Vertebral Efficacy with Risedronate Therapy (VERT) studies who received either risedronate 5 mg or placebo, daily risedronate reduced the risk of clinical vertebral fractures within 6 months (RR = 0.08, 95% CI 0.01-0.63), and by 69% at 1 year (RR = 0.31, 95% CI 0.12, 0.78). At 1 year, risedronate also reduced the risk of moderate-to-severe radiographically-defined vertebral fractures by 71% (RR = 0.29 95% CI 0.16, 0.54). Height loss was attenuated with treatment, most notably in patients who experienced new vertebral fractures, with a median difference of 0.73 cm compared with subjects receiving placebo (p = 0.005). CONCLUSION: Risedronate reduces the risk of clinical vertebral fractures in postmenopausal women with osteoporosis within 6 months of commencing treatment.

Body Height↗
PubMed2004

Exogenous testosterone or testosterone with finasteride increases bone mineral density in older men with low serum testosterone.

Older men, particularly those with low serum testosterone (T) levels, might benefit from T therapy to improve bone mineral density (BMD) and reduce fracture risk. Concerns exist, however, about the impact of T therapy on the prostate in older men. We hypothesized that the combination of T and finasteride (F), a 5 alpha-reductase inhibitor, might increase BMD in older men without adverse effects on the prostate. Seventy men aged 65 yr or older, with a serum T less than 12.1 nmol/liter on two occasions, were randomly assigned to receive one of three regimens for 36 months: T enanthate, 200 mg im every 2 wk with placebo pills daily (T-only); T enanthate, 200 mg every 2 wk with 5 mg F daily (T+F); or placebo injections and pills (placebo). Low BMD was not an inclusion criterion. We obtained serial measurements of BMD of the lumbar spine and hip by dual x-ray absorptiometry. Prostate-specific antigen (PSA) and prostate size were measured at baseline and during treatment to assess the impact of therapy on the prostate. Fifty men completed the 36-month protocol. By an intent-to-treat analysis including all men for as long as they contributed data, T therapy for 36 months increased BMD in these men at the lumbar spine [10.2 +/- 1.4% (mean percentage increase from baseline +/- SEM; T-only) and 9.3 +/- 1.4% (T+F) vs. 1.3 +/- 1.4% for placebo (P < 0.001)] and in the hip [2.7 +/- 0.7% (T-only) and 2.2 +/- 0.7% (T+F) vs. -0.2 +/- 0.7% for placebo, (P < or = 0.02)]. Significant increases in BMD were seen also in the intertrochanteric and trochanteric regions of the hip. After 6 months of therapy, urinary deoxypyridinoline (a bone-resorption marker) decreased significantly compared with baseline in both the T-only and T+F groups (P < 0.001) but was not significantly reduced compared with the placebo group. Over 36 months, PSA increased significantly from baseline in the T-only group (P < 0.001). Prostate volume increased in all groups during the 36-month treatment period, but this increase was significantly less in the T+F group compared with both the T-only and placebo groups (P = 0.02). These results demonstrate that T therapy in older men with low serum T increases vertebral and hip BMD over 36 months, both when administered alone and when combined with F. This finding suggests that dihydrotestosterone is not essential for the beneficial effects of T on BMD in men. In addition, the concomitant administration of F with T appears to attenuate the impact of T therapy on prostate size and PSA and might reduce the chance of benign prostatic hypertrophy or other prostate-related complications in older men on T therapy. These findings have important implications for the prevention and treatment of osteoporosis in older men with low T levels.

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PubMed2004

Official positions of the international society for clinical densitometry.

The International Society for Clinical Densitometry (ISCD) periodically holds Position Development Conferences for the purpose of establishing standards and guidelines for indications, acquisition, and interpretation of bone density tests. Topics are selected for consideration by the ISCD Scientific Advisory Committee, reviewed by scientific working groups, and presented to an international panel of experts. Topic categories addressed to date include indications for bone density testing, selection of reference databases for T-scores and Z-scores, clinical applications for central and peripheral bone densitometry, serial bone density testing, instrument precision assessment, phantom scanning and calibration testing, requirements for a bone density report, nomenclature, and diagnosis of osteoporosis in postmenopausal women, premenopausal women, men, and children. After an open session for public comment and discussion, the panel convenes for consideration of each topic and makes recommendations for positions to the ISCD Board of Directors. Recommendations that are accepted become the Official Positions of the ISCD. This Special Report summarizes the methodology of the ISCD Position Development Conferences and presents selected Official Positions of general interest.

Absorptiometry, Photon↗
PubMed2004

Standards and guidelines for performing central dual-energy x-ray absorptiometry in premenopausal women, men, and children.

The Canadian Panel of the International Society for Clinical Densitometry has developed standards in order to establish the minimum level of acceptable performance for the practice of bone densitometry in Canada. Previously, this group addressed the performance of densitometry in postmenopausal women. This report addresses the use of densitometry in men, premenopausal women, and children with a focus on dual-energy X-ray absorptiometry.

Absorptiometry, Photon↗
PubMed2004

Relationship between changes in bone mineral density and vertebral fracture risk associated with risedronate: greater increases in bone mineral density do not relate to greater decreases in fracture risk.

Low bone mineral density (BMD) is correlated with increased fracture risk. Whether greater BMD increases induced by osteoporosis drugs are related to greater decreases in fracture risk is controversial. We analyzed the relationship between BMD change and fracture risk in postmenopausal osteoporotic women receiving antiresorptive treatment. The analysis combined data from three pivotal risedronate fracture end-point trials. Women received risedronate (n = 2047) or placebo (n = 1177) daily for up to 3 yr. The BMD and vertebral radiographs were assessed periodically during 3 yr. The estimated risk of new vertebral fracture was compared between patients whose BMD increased and those whose BMD decreased. Risedronate-treated patients whose BMD decreased were at a significantly greater risk (p = 0.003) of sustaining a vertebral fracture than patients whose BMD increased. The fracture risk was similar (about 10%) in risedronate-treated patients whose increases in BMD were < 5% (the median change from baseline) and in those whose increases were >/= 5% (p = 0.453). The changes in lumbar spine BMD explained only 18% (95% confidence interval [CI], 10%, 26%; p < 0.001) of risedronate's vertebral fracture efficacy. Although patients showing an increase in BMD had a lower fracture risk than patients showing a decrease in BMD, greater increases in BMD did not necessarily predict greater decreases in fracture risk.

Absorptiometry, Photon↗
PubMed2004

The American College of Endocrinology and Endocrine University.

Subspecialty training in endocrinology depends in part on local expertise, with fellows having "hands-on" experience in some areas but only "book knowledge" in others. To provide more uniform training in new technologies, The American College of Endocrinology developed Endocrine University, which provides on-site didactic and interactive sessions on thyroid ultrasound, bone densitometry, and other topics over 6 to 7 days. The inaugural event in 2002 was attended by 137 fellows. A second conference in 2003 had capacity attendance of 143. A third course is scheduled for 2004. Fellows pay a token registration fee; the College provides grants to defray the cost of registration, travel, etc. Financial support comes from the College and industry, with plans for an endowment to sustain the program. Fellows value the educational sessions and also the unique opportunity to meet and visit with their peers. This innovative program can serve as a model for other specialties.

Endocrinology↗
PubMed2003

Effects of estrogen plus progestin on risk of fracture and bone mineral density: the Women's Health Initiative randomized trial.

CONTEXT: In the Women's Health Initiative trial of estrogen-plus-progestin therapy, women assigned to active treatment had fewer fractures. OBJECTIVE: To test the hypothesis that the relative risk reduction of estrogen plus progestin on fractures differs according to risk factors for fractures. DESIGN, SETTING, AND PARTICIPANTS: Randomized controlled trial (September 1993-July 2002) in which 16 608 postmenopausal women aged 50 to 79 years with an intact uterus at baseline were recruited at 40 US clinical centers and followed up for an average of 5.6 years. INTERVENTION: Women were randomly assigned to receive conjugated equine estrogen, 0.625 mg/d, plus medroxyprogesterone acetate, 2.5 mg/d, in 1 tablet (n = 8506) or placebo (n = 8102). MAIN OUTCOME MEASURES: All confirmed osteoporotic fracture events that occurred from enrollment to discontinuation of the trial (July 7, 2002); bone mineral density (BMD), measured in a subset of women (n = 1024) at baseline and years 1 and 3; and a global index, developed to summarize the balance of risks and benefits to test whether the risk-benefit profile differed across tertiles of fracture risk. RESULTS: Seven hundred thirty-three women (8.6%) in the estrogen-plus-progestin group and 896 women (11.1%) in the placebo group experienced a fracture (hazard ratio [HR], 0.76; 95% confidence interval [CI], 0.69-0.83). The effect did not differ in women stratified by age, body mass index, smoking status, history of falls, personal and family history of fracture, total calcium intake, past use of hormone therapy, BMD, or summary fracture risk score. Total hip BMD increased 3.7% after 3 years of treatment with estrogen plus progestin compared with 0.14% in the placebo group (P<.001). The HR for the global index was similar across tertiles of the fracture risk scale (lowest fracture risk tertile, HR, 1.20; 95% CI, 0.93-1.58; middle tertile, HR, 1.23; 95% CI, 1.04-1.46; highest tertile, HR, 1.03; 95% CI, 0.88-1.24) (P for interaction =.54). CONCLUSIONS: This study demonstrates that estrogen plus progestin increases BMD and reduces the risk of fracture in healthy postmenopausal women. The decreased risk of fracture attributed to estrogen plus progestin appeared to be present in all subgroups of women examined. When considering the effects of hormone therapy on other important disease outcomes in a global model, there was no net benefit, even in women considered to be at high risk of fracture.

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PubMed2003

Use of matched historical controls to evaluate the anti-fracture efficacy of once-a-week risedronate.

Placebo controls are essential to assess anti-fracture efficacy of new osteoporosis therapies, but inclusion of a placebo arm in a subsequent clinical trial may be limited by practical or ethical considerations; in these cases, use of an historical control may be appropriate. A recent active-controlled study of risedronate 35 mg once a week demonstrated that this regimen produces increases in bone mineral density (BMD) that are comparable to those seen with the risedronate 5 mg daily dose, which has proven anti-fracture efficacy. To assess the anti-fracture efficacy of this new regimen, we have analyzed the fracture data collected in an active controlled study of risedronate dosing regimens (the Once-a-Week study) using matched historical control data from previous placebo-controlled trials. Women in the Once-a-Week study were matched for age, years since menopause, BMD, and prevalent vertebral fracture status, with placebo patients in the Vertebral Efficacy of Risedronate Therapy (VERT) trials forming an historical placebo group. We also constructed an historical active treatment group from the 5 mg daily arm of the VERT trials for comparison with the 5 mg daily and 35 mg once weekly treatment groups in the Once-a-Week study. Data were obtained from the risedronate 5 mg daily group (n=480) and 35 mg once-a-week group (n=485) in the Once-a-Week study and historical control groups representing daily placebo patients (n=114, matched from 993) and risedronate 5 mg daily patients (n=120; matched from 990) in the VERT studies. Patients received calcium supplementation (1000 mg daily); vitamin D was given if baseline serum 25-hydroxyvitamin D levels were low. Over 1 year, new vertebral fracture risk in the 35 mg once-a-week group was reduced by 77% relative to the historical placebo group (1.2% versus 5.0%; RR 0.23; 95% CI, 0.54 to 0.91, P=0.018), similar to the 1-year risk reduction observed in the VERT trials of risedronate 5 mg daily (61-65%). The incidence of new vertebral fractures in the three active treatment groups was similar: 1.7% in the historical risedronate 5 mg group, 1.5% in the risedronate 5 mg daily group from the Once-a-Week study, and 1.2% in the 35 mg once-a-week group. Risedronate 35 mg once a week appears as effective as the 5 mg daily dose in reducing the risk of new vertebral fractures in the first year of treatment. The use of appropriate historical control data provides an approach to the assessment of fracture effects in osteoporosis trials for which placebo-controlled data are not available.

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PubMed2003

Bisphosphonate treatment of osteoporosis.

Bisphosphonates represent the agents of choice for most patients with osteoporosis. They are the best studied of all agents for the prevention of bone loss and reduction in fractures. They increase BMD, primarily at the lumbar spine, but also at the proximal femur. In patients who have established osteoporosis, bisphosphonates reduce the risk of vertebral fractures, and are the only agents in prospective trials to reduce the risk of hip fractures and other nonvertebral fractures. Bisphosphonates reduce the risk of fracture quickly. The risk of radiographic vertebral deformities is reduced after 1 year of treatment with risedronate [68]. The risk of clinical vertebral fractures is reduced after 1 year of treatment with alendronate [69] and just 6 months' treatment with risedronate [157]. The antifracture effect of risedronate has been shown to continue through 5 years of treatment [158]. Alendronate and risedronate are approved by the FDA for prevention of bone loss in recently menopausal women, for treatment of postmenopausal osteoporosis, and for prevention (risedronate) and treatment (alendronate and risedronate) of glucocorticoid-induced osteoporosis. Alendronate is also approved for treatment of osteoporosis in men. Other bisphosphonates (etidronate for oral use, pamidronate and zoledronate for intravenous infusion) are also available and can be used off label for patients who cannot tolerate approved agents. Although bisphosphonates combined with estrogen or raloxifene produce greater gains in bone mass compared with single-agent treatment, the use of two antiresorptive agents in combination cannot be recommended because the benefit on fracture risk has not been demonstrated and because of increased cost and side effects.

Bone Density↗
PubMed2003

Position Development Conference.

In a series of three published articles, the International Society for Clinical Densitometry has recorded the findings reached by an expert panel at the ISCD Position Development Conference held in July 2001. The key elements of those papers have been reviewed in this executive summary. It should be emphasized that the ISCD recommendations are not meant to serve as rigid guidelines or to replace clinical judgment. The recommendations will be reviewed and updated periodically as more data become available. A second Position Development Conference will be held in July 2003 in Cincinnati, OH. For information, visit the ISCD web site: http://www.iscd.org/.

Absorptiometry, Photon↗
PubMed2003

Risedronate prevents new vertebral fractures in postmenopausal women at high risk.

Independent risk factors for fracture include advanced age, preexisting fractures, and low bone mineral density. Rised-ronate has been shown in several large trials to be safe and effective for patients with osteoporosis, but its effects in populations at high risk are not well characterized. To determine the effect of risedronate on vertebral fracture in high-risk subjects, we pooled data from two randomized, double-blind studies [Vertebral Efficacy with Risedronate Therapy (VERT) Multinational (VERT-MN) and VERT-North America (VERT-NA)] in 3684 postmenopausal osteoporotic women treated with placebo or risedronate 2.5 or 5 mg/d and analyzed fracture risk in subgroups of subjects at high risk for fracture due to greater age or more prevalent fractures (vs. median for overall study population), or lower bone mineral density (T-score, -2.5 or less). Fractures were diagnosed by quantitative and semiquantitative assessment of radiographs at baseline and 1 yr. In the overall population, treatment for 1 yr with risedronate 5 mg/d reduced the risk of new vertebral fractures by 62% vs. control (relative risk, 0.38; 95% confidence interval, 0.25, 0.56; P < 0.001) and of multiple new vertebral fractures by 90% vs. control (relative risk, 0.10; 95% confidence interval, 0.04, 0.26; P < 0.001). Consistent risk reductions were observed at 1 yr in the risedronate-treated high-risk subgroups. Significant reduction in fracture risk after 1 yr is an important benefit in patients at high risk for fracture because, without treatment, these patients are likely to sustain new fractures in the near term.

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