Biomedical subjects

Florent Richy

Publications and source records attributed to Florent Richy.

13 recordsLinked to original sources

PubMed2005

D-hormone analog alfacalcidol: an update on its role in post-menopausal osteoporosis and rheumatoid arthritis management.

Alfacalcidol (1-alpha-hydroxyvitamin D3) is a non-endogenous analog of vitamin D which can bypass the renal and intestinal regulatory mechanisms that control the production of calcitriol (1,25-hydroxyvitamin D3, the active form of vitamin D, D-Hormone). Alfacalcidol may be metabolized into calcitriol with a limited risk of hypercalcemia. Alfacalcidol and calcitriol have been evaluated in animal and human studies assessing their effects on bone mineral density and fracture rates. More recently, they have been shown to produce beneficial effects in muscle, immune system, and autoimmune diseases, including rheumatoid arthritis. This paper discusses the therapeutic efficacy of alfacalcidol in reports in which it has been proposed as an interesting alternative to vitamin D or calcitriol. Some recent findings about general metabolism and regulation of vitamin D and its analogs are discussed. The biological and clinical effects of alfacalcidol in post-menopausal osteoporosis are reviewed, followed by critical appraisal of its efficacy in preventing bone loss and falls in the elderly. The last two sections discuss the role of D analogs in regulating the immune system, with particular regard to rheumatoid arthritis. The main results of this review show that alfacalcidol may have a wider range of therapeutic applicability, beyond simply restricting it to patients in hemodialysis or peritoneal dialysis with high serum levels of intact PTH.

Accidental Falls↗

PubMed2005

Controlled whole body vibration to decrease fall risk and improve health-related quality of life of nursing home residents.

OBJECTIVE: To investigate the effects of whole body vibration in the elderly. DESIGN: Randomized controlled trial. SETTING: Nursing home. PARTICIPANTS: Forty-two elderly volunteers. INTERVENTIONS: Six-week vibration intervention plus physical therapy (PT) (n=22) or PT alone (n=20). MAIN OUTCOME MEASURES: We assessed gait and body balance using the Tinetti test (maximum scores of 12 for gait, 16 for body balance, 28 for global score), motor capacity using the Timed Up & Go (TUG) test, and health-related quality of life (HRQOL) using the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). RESULTS: After 6 weeks, the vibration intervention group improved by a mean +/- standard deviation of 2.4+/-2.3 points on the gait score compared with no score change in the control group ( P <.001). The intervention group improved by 3.5+/-2.1 points on the body balance score compared with a decrease of 0.3+/-1.2 points in the control group ( P <.001). TUG test time decreased by 11.0+/-8.6 seconds in the treated group compared with an increase of 2.6+/-8.8 seconds in the control group ( P <.001). The intervention group had significantly greater improvements from baseline on 8 of 9 items on the SF-36 compared with the control group. CONCLUSIONS: Controlled whole body vibration can improve elements of fall risk and HRQOL in elderly patients.

Accidental Falls↗

PubMed2005

Importance of alfacalcidol in clinical conditions characterized by high rate of bone loss.

In postmenopausal osteoporosis, the administration of alfacalcidol to women resulted in an increase in trabecular bone mineral density (BMD), prevention of cortical bone loss, and a significant reduction in the incidence of further vertebral fractures. There is now robust evidence that alfacalcidol may be particularly active in conditions characterized by an increased rate of bone loss. Alfacalcidol 1 microg/day fully prevented vertebral bone loss over 3 years in women after the first year of menopause. In a large cohort of individuals starting treatment with high dose corticosteroid (CS, 46.6 mg equivalent prednisolone per day), the spinal bone loss observed in untreated patients was fully prevented by administration of 1 microg/day alfacalcidol. In patients with established CS-induced osteoporosis, with or without prevalent vertebral fractures, 1 microg/day of alfacalcidol, given for 3 years, increased lumbar spine density, reduced back pain, and showed a significant reduction in the rate of new vertebral fractures, compared to native vitamin D. In cardiac transplant recipients, alfacalcidol and calcium reduced spinal and femoral bone loss, compared to a control group treated with etidronate and calcium. Alfacalcidol-treated patients experienced fewer new vertebral fractures over the 2-year followup. When alfacalcidol and vitamin D3 were compared in elderly women with radiologic evidence of vertebral fracture, fractional calcium absorption was increased after 3 months with alfacalcidol but was unchanged with vitamin D3. In a recent metaanalysis of 14 studies of native vitamin D and 19 studies of D-hormone analogs (alfacalcidol and calcitriol), the D-analogs exerted a higher preventive effect on bone loss and fracture rates in patients with no exposure to CS. In head-to-head studies comparing D-analogs and native vitamin D in patients receiving CS, this metaanalysis identified significant effects favoring D-analogs for femoral neck BMD and spinal fractures. In conclusion, improvement in bone turnover, increase in BMD, and reduction in fracture rates have been described during alfacalcidol treatment in situations characterized by a high rate of bone loss, including CS-induced osteoporosis, early postmenopausal bone loss, and organ transplant. Compared to plain vitamin D, alfacalcidol exerts higher bone-protective effects, thus allowing the doses to be minimized and lowering the risk of adverse effects, including hypercalcemia.

Adrenal Cortex Hormones↗

PubMed2004

Performance of osteoporosis risk assessment tools in postmenopausal women aged 45-64 years.

Osteoporosis risk factor assessment is of uncertain utility in women under 65 years of age. Previous comparative studies of osteoporosis risk assessment tools were not stratified by age. We compared the discriminatory ability of three previously validated osteoporosis risk assessment tools in a referral population of postmenopausal women aged 45-64 years (n=2539) and aged 65-96 years (n=1496) seen at a university-based outpatient osteoporosis center in Belgium. Risk scores for the Osteoporosis Self-assessment Tool, Osteoporosis Risk Assessment Instrument, and Simple Calculated Osteoporosis Risk Estimation were calculated for each patient. The reference standard was osteoporosis at the femoral neck, defined as a T-score < or =-2.5 based on bone mineral density measured by dual energy X-ray absorptiometry. Osteoporosis was present in 139 of 2539 (5.5%) women aged 45-64 years and 241 of 1496 (16.1%) women aged 65 years or older. The tools had similar overall discriminatory ability to identify women with osteoporosis [area under the ROC curve 0.750-0.768, P=0.23 for women aged 45-64 years; area under the ROC curve 0.745-0.762, P=0.06 for women aged 65 years or older (P>0.05 indicates no difference among tools)]. The likelihood ratios for the high-risk score categories ranged from 3.60 to 6.73 for the younger women and 3.45 to 6.99 for the older women when different score thresholds were set to maximize the performance of each tool in each age group. We conclude that the diagnostic accuracy of three osteoporosis risk assessment tools was similar in postmenopausal women aged 45-64 years and women aged 65 years or older. Use of structured risk assessment tools to identify women at high risk of osteoporosis in the early postmenopausal period warrants further study. Of the three tools evaluated, the OST is the simplest and has the best potential for use in clinical practice.

Aged↗

PubMed2004

Primary prevention of osteoporosis: mass screening scenario or prescreening with questionnaires? An economic perspective.

UNLABELLED: This study focuses on the controversy surrounding selective approaches to screen for osteoporosis. Seven screening approaches were compared in terms of cost-effectiveness and incremental cost-effectiveness ratios in a sample of 4035 postmenopausal women. Our results show that certain prescreening strategies are more efficient than DXA-based approaches. These results are of considerable value for health policy decision-makers and the scientific community. INTRODUCTION: There is no general consensus on the most efficient strategy to use bone densitometry for osteoporosis screening. Two distinct approaches have progressively emerged: mass screening using DXA and prescreening strategies using user-friendly risk indices. This study was designed to compare the efficiency of these approaches. MATERIALS AND METHODS: A database of 4035 medical records from postmenopausal women above 45 years was analyzed. In the first scenario, women were systematically referred to DXA if above 45, 50, or 65 years of age. The second scenario involved the validated prescreening tools SCORE, ORAI, OST, and OSIRIS and assessed two separate ways of handling their results (theoretical and pragmatic). The cost of a DXA test was set as the median Belgian value: 40.14 Euros. All strategies were compared in terms of cost exposed per osteoporotic patient detected and in terms of incremental cost-effectiveness ratios. RESULTS: In the systematic DXA strategies, the cost per patient detected ranged from 123 Euros when measuring all women >45 years of age to 91 Euros when focusing on women >65 years of age. The corresponding percentage of cases detected ranged from 100% (age > 45 years) to 50% (age > 65 years). When considering prescreening under the theoretical and pragmatic scenarios, the OSIRIS index provided the best efficiency, with costs of 74 Euros (theoretical) to 85 Euros (pragmatic) per case detected, followed by ORAI (75 Euros and 96 Euros), OST (84 Euros and 94 Euros), and SCORE (96 Euros and 103 Euros). The corresponding percentage of cases detected ranged from 89% (SCORE) to 75% (OSIRIS). The cost-effectiveness analysis showed that mass screening strategies over 50 and 65 years of age and using ORAI were best. CONCLUSIONS: Our study sets the grounds for considering, in a health economics perspective, prescreening tools as valuable, cost-effective, approaches to significantly reduce the economic burden of osteoporosis screening.

Absorptiometry, Photon↗

PubMed2004

Efficacy of alphacalcidol and calcitriol in primary and corticosteroid-induced osteoporosis: a meta-analysis of their effects on bone mineral density and fracture rate.

Vitamin D metabolites alphacalcidol and calcitriol (D-hormones) have been investigated for two decades, but few and conflicting results are available from high-quality randomized controlled trials. Our objectives were to provide an evidence-based update quantitatively summarizing their efficacy on bone mineral density (BMD) and fracture rate. We performed a systematic research of any randomized controlled trial containing relevant data, peer review, data extraction and quality scoring blinded for authors and data sources, and comprehensive meta-analyses of the relevant data. Inclusion criteria were: randomized controlled study, calcitriol or alphacalcidol, BMD or fractures in healthy/osteopenic/osteoporotic patients exposed or not to corticosteroids (CS). Analyses were performed in a conservative fashion using professional dedicated softwares and stratified by outcome, target patients, study quality, and control-group type. Results were expressed as effect size (ES) for bone loss or relative risk (RR) for fracture while allocated to D-hormones vs control. Publication bias and robustness were investigated. Of the trials that were retrieved and subsequently reviewed, 17 papers fitted the inclusion criteria and were assessed. Quality scores ranged from 20 to 100%, the mean (standard deviation) being 72 (22)%. Calcitriol and alphacalcidol were found to have the same efficacy on all outcomes at p>0.13. We globally assessed D-hormones effects in preventing bone loss in patients not exposed to CS, and found positive effect: ES=0.39 ( p<0.001). For lumbar spine, this particular effect was 0.43 ( p<0.001). D-hormones significantly reduced the overall fracture rates: RR=0.52 (0.46; 0.59) and both vertebral and non-vertebral fractures: RR=0.53 (0.47; 0.60) and RR=0.34 (0.16; 0.71), respectively. No statistical difference in response was observed between results from studies on healthy and osteoporotic patients or depending on the fact that controls were allowed to calcium supplementation. Treatment with D-hormones was evaluated for maintaining spinal bone mass in five trials of patients with CS-induced osteoporosis, and provided ES=0.43 at p<0.001. Only two studies specifically addressed the effects of calcitriol on spinal fracture rate. None of them provided significant results, and the global RR did not reach the significance level as well: RR=0.33 (0.07; 1.51). Our data demonstrated efficacy for DH on bone loss and fracture prevention in patients not exposed to CS and on bone loss in patients exposed to CS, in the light of the most reliable scientific evidence. Their efficacy in reducing the number of fractures in patients exposed to CS remains to be determined.

Adrenal Cortex Hormones↗

PubMed2004

Osteoporosis prevalence in men varies by the normative reference.

Controversy surrounds which normative data should be used to estimate osteoporosis prevalence in men. Prevalence estimates may vary significantly when different normative standards are applied. Five normative datasets (NHANES female norms, local female norms, Hologic densitometer manufacturer female norms, NHANES male norms, Hologic male norms) were used to estimate the prevalence of osteoporosis by World Health Organization diagnostic criteria in a study population of 311 consecutive men between the age of 30 and 91 (mean 60.3 yr) referred to an outpatient osteoporosis center between January 1996 and December 1998. Statistically significant variations were seen in osteoporosis prevalence measured at three anatomical sites. The greatest relative variation was seen for the total femur, where osteoporosis prevalence ranged from 7.0% (NHANES and Hologic female norms) to 15.6% (NHANES male norms). The least relative variation was seen at the lumbar spine, where prevalence ranged from 18.1% (Hologic female norms) to 29.6% (local female norms). When considering osteoporosis at any site, prevalence was lowest (23.5%) based on Hologic female norms and highest (35.8%) based on local female norms. Interpretation of prevalence data should include an assessment of how normative standards influence reporting of the population at high risk of fracture.

Adult↗

PubMed2004

Health-related quality of life in total hip and total knee arthroplasty. A qualitative and systematic review of the literature.

BACKGROUND: Total hip and total knee arthroplasties are well accepted as reliable and suitable surgical procedures to return patients to function. Health-related quality-of-life instruments have been used to document outcomes in order to optimize the allocation of resources. The objective of this study was to review the literature regarding the outcomes of total hip and knee arthroplasties as evaluated by health-related quality-of-life instruments. METHODS: The Medline and EMBASE medical literature databases were searched, from January 1980 to June 2003, to identify relevant studies. Studies were eligible for review if they met the following criteria: (1). the language was English or French, (2). at least one well-validated and self-reported health-related quality of life instrument was used, and (3). a prospective cohort study design was used. RESULTS: Of the seventy-four studies selected for the review, thirty-two investigated both total hip and total knee arthroplasties, twenty-six focused on total hip arthroplasty, and sixteen focused on total knee arthroplasty exclusively. The most common diagnosis was osteoarthritis. The duration of follow-up ranged from seven days to seven years, with the majority of studies describing results at six to twelve months. The Short Form-36 and the Western Ontario and McMaster University Osteoarthritis Index, the most frequently used instruments, were employed in forty and twenty-eight studies, respectively. Seventeen studies used a utility index. Overall, total hip and total knee arthroplasties were found to be quite effective in terms of improvement in health-related quality-of-life dimensions, with the occasional exception of the social dimension. Age was not found to be an obstacle to effective surgery, and men seemed to benefit more from the intervention than did women. When improvement was found to be modest, the role of comorbidities was highlighted. Total hip arthroplasty appears to return patients to function to a greater extent than do knee procedures, and primary surgery offers greater improvement than does revision. Patients who had poorer preoperative health-related quality of life were more likely to experience greater improvement. CONCLUSIONS: Health-related quality-of-life data are valuable, can provide relevant health-status information to health professionals, and should be used as a rationale for the implementation of the most adequate standard of care. Additional knowledge and scientific dissemination of surgery outcomes should help to ensure better management of patients undergoing total hip or total knee arthroplasty and to optimize the use of these procedures.

Age Factors↗

PubMed2004

Development and validation of the ORACLE score to predict risk of osteoporosis.

OBJECTIVE: To develop and validate a composite index, the Osteoporosis Risk Assessment by Composite Linear Estimate (ORACLE), that includes risk factors and ultrasonometric outcomes to screen for osteoporosis. SUBJECTS AND METHODS: Two cohorts of postmenopausal women aged 45 years and older participated in the development (n = 407) and the validation (n = 202) of ORACLE. Their bone mineral density was determined by dual energy x-ray absorptiometry and quantitative ultrasonometry (QUS), and their historical and clinical risk factors were assessed (January to June 2003). Logistic regression analysis was used to select significant predictors of bone mineral density, whereas receiver operating characteristic (ROC) analysis was used to assess the discriminatory performance of ORACLE. RESULTS: The final logistic regression model retained 4 biometric or historical variables and 1 ultrasonometric outcome. The ROC areas under the curves (AUCs) for ORACLE were 84% for the prediction of osteoporosis and 78% for low bone mass. A sensitivity of 90% corresponded to a specificity of 50% for identification of women at risk of developing osteoporosis. The corresponding positive and negative predictive values were 86% and 54%, respectively, in the development cohort. In the validation cohort, the AUCs for identification of osteoporosis and low bone mass were 81% and 76% for ORACLE, 69% and 64% for QUS T score, 71% and 68% for QUS ultrasonometric bone profile index, and 76% and 75% for Osteoporosis Self-assessment Tool, respectively. ORACLE had the best discriminatory performance in identifying osteoporosis compared with the other approaches (P < .05). CONCLUSION: ORACLE exhibited the highest discriminatory properties compared with ultrasonography alone or other previously validated risk indices. It may be helpful to enhance the predictive value of QUS.

Absorptiometry, Photon↗

PubMed2003

Structural and symptomatic efficacy of glucosamine and chondroitin in knee osteoarthritis: a comprehensive meta-analysis.

OBJECTIVE: To assess the structural and symptomatic efficacy of oral glucosamine sulfate and chondroitin sulfate in knee osteoarthritis through independent meta-analyses of their effects on joint space narrowing, Lequesne Index, Western Ontario MacMaster University Osteoarthritis Index (WOMAC), visual analog scale for pain, mobility, safety, and response to treatment. METHODS: An exhaustive systematic research of randomized, placebo-controlled clinical trials published or performed between January 1980 and March 2002 that assessed the efficacy of oral glucosamine or chondroitin on gonarthrosis was performed using MEDLINE, PREMEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Current Contents, BIOSIS Previews, HealthSTAR, EBM Reviews, manual review of the literature and congressional abstracts, and direct contact with the authors and manufacturers of glucosamine and chondroitin. Inclusion, quality scoring, and data abstraction were performed systematically by 2 independent reviewers who were blinded to sources and authors. Conservative approaches were used for clear assessment of potential efficacy. RESULTS: Our results demonstrated a highly significant efficacy of glucosamine on all outcomes, including joint space narrowing and WOMAC. Chondroitin was found to be effective on Lequesne Index, visual analog scale pain, mobility, and responding status. Safety was excellent for both compounds. CONCLUSIONS: Our study demonstrates the structural efficacy of glucosamine and indistinguishable symptomatic efficacies for both compounds. Regarding the relatively sparse data on glucosamine and joint space narrowing and the absence of data on structural effects of chondroitin, further studies are needed to investigate the relationship among time, dose, patient baseline characteristics, and structural efficacy for an accurate, disease-modifying characterization of these 2 compounds.

Administration, Oral↗

PubMed2003

Interest of biochemical markers of bone turnover for long-term prediction of new vertebral fracture in postmenopausal osteoporotic women.

OBJECTIVE: To analyse the interest of baseline levels and short-term (3-months) changes in serum osteocalcin (BGP), serum bone-specific alkaline phosphatase (BALP) and urinary C-telopeptide of type I collagen/creatinine ratio (U-CTX) to predict 3-years changes in bone mineral density (BMD) and spinal deformity index (SDI) in postmenopausal osteoporotic women. METHODS: Data were derived from a cohort of 603 osteoporotic women corresponding to the placebo arm of a 3-years prospective, double-blind study. RESULTS: Baseline values of BALP, BGP and U-CTX were negatively and significantly correlated with baseline spinal BMD. Significant correlations were also observed between the changes in BMD observed after 36 months at the spine and baseline BALP (r=0.20, P=0.0001), BGP (r=0.09, P=0.05) and U-CTX (r=-0.11, P=0.02). At 3 years, 71 women (15.9%) showed an increase in their SDI, corresponding to the occurrence of at least one new vertebral deformity. Baseline values of the four bone turnover markers (BTM) were not significantly related to the occurrence of new vertebral deformities. However, when considering the changes in the BTM observed after 3-months of follow-up, BGP (P=0.003) and U-CTX (P=0.047) were identified as significant predictors of an increase of SDI. The associated odds ratios (95% confidence interval (CI)) were 10.922 (2.218-53.78) for unit changes of log BGP and 1.369 (1.003-1.867) for unit changes of logU-CTX. The relative risk (RR) (IC 95%) of having a new vertebral fracture over 36 months was 0.31 (0.15-0.65) when being in the lowest quartile of 3-months changes in BGP as compared with the highest. CONCLUSION: We conclude that two sequential measurements of BGP and U-CTX performed at 3-months intervals could be of interest to identify postmenopausal osteoporotic women with the highest risk to present new vertebral deformities.

Aged↗

PubMed2003

Inhaled corticosteroids effects on bone in asthmatic and COPD patients: a quantitative systematic review.

Deleterious effect of oral corticosteroids on bone has been well documented, whereas this remains debated for inhaled ones (ICS). Our objectives were to analyze the effects of ICS on bone mineral density, fracture risk and bone markers. We performed an exhaustive systematic research of all controlled trials potentially containing pertinent data, peer-reviewed by a dedicated WHO expert group, and comprehensive meta-analyses of the data. Inclusion criteria were ICS, and BMD/markers/fractures in asthma/chronic obstructive pulmonary diseases (COPD) and healthy patients. Analyses were performed in a conservative fashion using professional dedicated softwares and stratified by outcome, study design and ICS type. Results were expressed as standardized mean difference/effect size (ES), relative risk (RR) or odds ratio (OR), depending on study design and outcome units. Publication bias was investigated. Twenty-three trials were reviewed; 11 papers fit the inclusion criteria and were assessed for the main analysis. Quality scores for the randomized controlled trials (RCTs) were 80%, 71% for the prospective cohort studies, and 78% for the retrospective cohort and cross-sectional studies. We globally assessed ICS effects on BMD and found deleterious effects: ES=0.61 ( p=0.001) for healthy subjects, and ES=0.27 ( p<0.001) for asthma/COPD patients. For these patients, this effect was 0.21 ( p<0.01) at the lumbar spine, and 0.26 ( p<0.001) at the hip or femoral neck. A single study evaluated the impact of ICS on hip fracture and reported an increased OR of 1.6 (1.24; 2.03). Lumbar fracture rate differences did not reach the level of statistical significance: 1.87 (0.5; 6.94). Osteocalcin and PICP were decreased and ICTP, pyridinoline and deoxypyridinoline levels were not significantly affected. Budesonide (BUD) appeared to be the ICS inducing the less deleterious effects on bone, followed by beclomethasone dipropionate (BDP) and triamcinolone (TRI). Publication bias investigation provided non-significant results. In our meta-analyses, BUD at a mean daily dose (SD) of 686 microg (158 microg), BDP at 703 microg (123 microg) and TRI at 1,000 microg (282 microg) were found to affect bone mineral density and markers in patients suffering from the two major respiratory diseases. These findings could have practical implication in the long-term management of asthmatic and COPD patients.

Administration, Inhalation↗

PubMed2003

Strategies for the prevention of hip fracture.

Hip fractures are associated with 10% to 20% excess mortality in the first year and cause functional disability in most survivors. An estimated 17% of white women in the United States will sustain a hip fracture after the age of 50 years. Despite the availability of evidence-based guidelines for hip fracture prevention, routine screening and preventive measures have not been incorporated into standard primary care practice. Many physicians lack adequate knowledge to initiate bone mineral density testing and treatment with preventive medications to decrease the incidence of osteoporosis and fractures. Furthermore, patients are less likely to request information about bone health than about diseases for which systematic screening and prevention protocols have been established. This review describes preventive measures to decrease hip fracture in postmenopausal women, including screening by bone mineral density testing, risk factor assessment, and chemoprevention. Existing guidelines are summarized, and dilemmas regarding their implementation are discussed.

Bone Density↗