Long-term follow-up of balloon-expandable valves according to the implantation strategy: insight from the DIRECTAVI trial.

BACKGROUND: Safety and feasibility of transcatheter aortic valve replacement (TAVR) without balloon aortic valvuloplasty (BAV) using the SAPIEN 3 balloon-expandable device has been previously demonstrated. The impact on long-term valve hemodynamic performances and outcomes remains however unknown. We evaluate long-term clinical and hemodynamic results according to the implant strategy (direct TAVR vs BAV pre-TAVR) in patients included in the DIRECTAVI randomized trial (NCT02729519). METHODS: Clinical and echocardiographic follow-up until January 2023 was performed for all patients included in the DIRECTAVI trial since 2016 (n = 228). The primary endpoint was incidence of moderate/severe hemodynamic valve deterioration (HVD), according to the Valve Academic Research defined Consortium-3 criteria (increase in mean gradient ≥10 mmHg resulting in a final mean gradient ≥20 mmHg, or new/worsening aortic regurgitation of 1 grade resulting in ≥ moderate aortic regurgitation). RESULTS: Median follow-up was 3.8 (2.2-4.7) years. Mean age at follow-up was 87 ± 6.7 years. No difference in incidence of HVD in the direct implantation group compared to the BAV group was found (incidence of 1.97 per 100 person-years and 1.45 per 100 person-years, respectively, P = 0.6). Prevalence of predicted prothesis-patient mismatch was low (n = 13 [11.4%] in the direct TAVR group vs n = 15 [13.2%] in BAV group) and similar between both groups (P = .7). Major outcomes including death, stroke, hospitalization for heart failure and pacemaker implantation were similar between both groups, (P = .4, P = .7, P = .3, and P = .3 respectively). CONCLUSION: Direct implantation of the balloon-expandable device in TAVR was not associated with an increased risk of moderate/severe HVD or major outcomes up to 6-year follow-up. These results guarantee wide use of direct balloon-expandable valve implantation, when feasible. CLINICAL TRIALS REGISTRATION NUMBER: NCT05140317.

Balloon predilation or direct valve implantation in TAVI for women: Insights from the DIRECTAVI study.

BACKGROUND: The randomized DIRECTAVI trial demonstrated safety and feasibility of transcatheter aortic valve implantation (TAVI) without balloon aortic valvuloplasty (BAV) using SAPIEN 3 balloon-expandable devices. However, the female population with smaller anatomy may have potential higher risk of residual gradient and/or mismatch. PURPOSE: We assessed the impact of BAV on the procedural success rate and clinical outcomes in the female population of the DIRECTAVI trial. METHODS: Between May 2016 and May 2018, 91 of the 250 patients included in the DIRECTAVI trial were women (38.6%), 45 of them (49.5%) were enrolled in the BAV group and 46 of them (50.5%) in the direct TAVI group. The primary endpoint was procedural success rate in women (Valve Academic Research Consortium-2 criteria). The secondary endpoint included evaluation of PPM and 1-month major adverse events according to the implantation stategy in women and comparison between men and women regarding major endpoints. RESULTS: The primary endpoint occurred in 29 women (64.4%) in the BAV group and in 34 women (73.9%) in the direct TAVI group (mean difference 9.47%; 95% confidence interval: 6.5%-25.4%; p = 0.045 for non-inferiority of the direct strategy). One-month major adverse events were similar between the 2 women groups. Procedural success was lower in women vs men (p = 0.01) due to higher incidence of moderate mismatches in women (p = 0.001) but with no significant difference regarding the implantation strategy (p = 0.4). CONCLUSION: Direct implantation of the balloon-expandable SAPIEN 3 valve was non-inferior to predilatation on procedural success in women. Incidence of moderate mismatch was higher in women but was not related to the implantation strategy.

Barriers and Facilitators to the Use of Clinical Decision Support Systems in Primary Care: A Mixed-Methods Systematic Review.

PURPOSE: To identify and quantify the barriers and facilitators to the use of clinical decision support systems (CDSSs) by primary care professionals (PCPs). METHODS: A mixed-methods systematic review was conducted using a sequential synthesis design. PubMed/MEDLINE, PsycInfo, Embase, CINAHL, and the Cochrane library were searched in July 2021. Studies that evaluated CDSSs providing recommendations to PCPs and intended for use during a consultation were included. We excluded CDSSs used only by patients, described as concepts or prototypes, used with simulated cases, and decision supports not considered as CDSSs. A framework synthesis was performed according to the HOT-fit framework (Human, Organizational, Technology, Net Benefits), then a quantitative synthesis evaluated the impact of the HOT-fit categories on CDSS use. RESULTS: A total of 48 studies evaluating 45 CDSSs were included, and 186 main barriers or facilitators were identified. Qualitatively, barriers and facilitators were classified as human (eg, perceived usefulness), organizational (eg, disruption of usual workflow), and technological (eg, CDSS user-friendliness), with explanatory elements. The greatest barrier to using CDSSs was an increased workload. Quantitatively, the human and organizational factors had negative impacts on CDSS use, whereas the technological factor had a neutral impact and the net benefits dimension a positive impact. CONCLUSIONS: Our findings emphasize the need for CDSS developers to better address human and organizational issues, in addition to technological challenges. We inferred core CDSS features covering these 3 factors, expected to improve their usability in primary care.

Oritatami: A Computational Model for Molecular Co-Transcriptional Folding.

We introduce and study the computational power of Oritatami, a theoretical model that explores greedy molecular folding, whereby a molecular strand begins to fold before its production is complete. This model is inspired by our recent experimental work demonstrating the construction of shapes at the nanoscale from RNA, where strands of RNA fold into programmable shapes during their transcription from an engineered sequence of synthetic DNA. In the model of Oritatami, we explore the process of folding a single-strand bit by bit in such a way that the final fold emerges as a space-time diagram of computation. One major requirement in order to compute within this model is the ability to program a single sequence to fold into different shapes dependent on the state of the surrounding inputs. Another challenge is to embed all of the computing components within a contiguous strand, and in such a way that different fold patterns of the same strand perform different functions of computation. Here, we introduce general design techniques to solve these challenges in the Oritatami model. Our main result in this direction is the demonstration of a periodic Oritatami system that folds upon itself algorithmically into a prescribed set of shapes, depending on its current local environment, and whose final folding displays the sequence of binary integers from 0 to N = 2 k - 1 with a seed of size O ( k ) . We prove that designing Oritatami is NP-hard in the number of possible local environments for the folding. Nevertheless, we provide an efficient algorithm, linear in the length of the sequence, that solves the Oritatami design problem when the number of local environments is a small fixed constant. This shows that this problem is in fact fixed parameter tractable (FPT) and can thus be solved in practice efficiently. We hope that the numerous structural strategies employed in Oritatami enabling computation will inspire new architectures for computing in RNA that take advantage of the rapid kinetic-folding of RNA.

A pooled analysis of vitamin D dose requirements for fracture prevention.

BACKGROUND: The results of meta-analyses examining the relationship between vitamin D supplementation and fracture reduction have been inconsistent. METHODS: We pooled participant-level data from 11 double-blind, randomized, controlled trials of oral vitamin D supplementation (daily, weekly, or every 4 months), with or without calcium, as compared with placebo or calcium alone in persons 65 years of age or older. Primary end points were the incidence of hip and any nonvertebral fractures according to Cox regression analyses, with adjustment for age group, sex, type of dwelling, and study. Our primary aim was to compare data from quartiles of actual intake of vitamin D (including each individual participant's adherence to the treatment and supplement use outside the study protocol) in the treatment groups of all trials with data from the control groups. RESULTS: We included 31,022 persons (mean age, 76 years; 91% women) with 1111 incident hip fractures and 3770 nonvertebral fractures. Participants who were randomly assigned to receive vitamin D, as compared with those assigned to control groups, had a nonsignificant 10% reduction in the risk of hip fracture (hazard ratio, 0.90; 95% confidence interval [CI], 0.80 to 1.01) and a 7% reduction in the risk of nonvertebral fracture (hazard ratio, 0.93; 95% CI, 0.87 to 0.99). By quartiles of actual intake, reduction in the risk of fracture was shown only at the highest intake level (median, 800 IU daily; range, 792 to 2000), with a 30% reduction in the risk of hip fracture (hazard ratio, 0.70; 95% CI, 0.58 to 0.86) and a 14% reduction in the risk of any nonvertebral fracture (hazard ratio, 0.86; 95% CI, 0.76 to 0.96). Benefits at the highest level of vitamin D intake were fairly consistent across subgroups defined by age group, type of dwelling, baseline 25-hydroxyvitamin D level, and additional calcium intake. CONCLUSIONS: High-dose vitamin D supplementation (≥800 IU daily) was somewhat favorable in the prevention of hip fracture and any nonvertebral fracture in persons 65 years of age or older. (Funded by the Swiss National Foundations and others.).

Identification of Low- versus High-Risk Acute Coronary Syndrome for a Selective ECG Monitoring Strategy.

BACKGROUND: While admission of patients with acute coronary syndromes (ACS) in cardiology intensive care unit (CICU) is usual, in-hospital major outcomes in lower risk patients may be evaluated after early coronary angiography according to the European guidelines. METHODS: Consecutive ACS patients were prospectively included after coronary angiography evaluation within 24 h and percutaneous coronary intervention (PCI), when required. Patients were classified as high- or low-risk according to hemodynamics, rhythmic state, ischemic and bleeding risks. Major in-hospital outcomes were assessed. RESULTS: From January to June 2021, 277 patients were enrolled (62.8% with ST-segment elevation myocardial infarction (STEMI) (n = 174); 37.2% with non-NSTEMI (NSTEMI) (n = 103). PCI was required for 260 patients (93.9%). Seventy-four patients (26.7%) were classified as low-risk (n = 47 NSTEMI; n= 27 STEMI) and 203 patients (73.3%) as high-risk of events. All patients were monitored in CICU. While 38 patients (18.7%) from the high-risk group reached the primary endpoint, mainly related to rhythmic or conduction disorder (n = 24, 11.8%) or unstable hemodynamics (n = 17; 8.4%), only 1 patient (1.3%) in the low-risk group had one major outcome (no fatal bleeding); p < 0.01. The negative predictive value of our patient stratification for the absence of major in-hospital outcome was 100% (CI95%: 100-100%) for STEMI and 97.9% [CI95%: 93.2-100%] for NSTEMI patients. CONCLUSIONS: Stratification of ACS patients after early coronary angiography and most of the time PCI, identify a population with very low risk of in-hospital events (1/4 of all ACS and 1/2 of NSTEMI) who may probably not require ECG monitoring and/or CICU admission. (NCT04378504).

Simplified TAVR Procedure: How Far Is It Possible to Go?

Increasing operators' experience and improvement of the technique have resulted in a drastic reduction in complications following transcatheter aortic valve replacement (TAVR) in patients with lower surgical risk. In parallel, the procedure was considerably simplified, with a routine default approach including local anesthesia in the catheterization laboratory, percutaneous femoral approach, radial artery as the secondary access, prosthesis implantation without predilatation, left ventricle wire pacing and early discharge. Thus, the "simplified" TAVR adopted in most centers nowadays is a real revolution of the technique. However, simplified TAVR must be accompanied upstream by a rigorous selection of patients who can benefit from a minimalist procedure in order to guarantee its safety. The minimalist strategy must not become dogmatic and careful pre-, per- and post-procedural evaluation of patients with well-defined protocols guarantee optimal care following TAVR. This review aims to evaluate the benefits and limits of the simplified TAVR procedure in a current and future vision.

Muscle regeneration affects Adeno Associated Virus 1 mediated transgene transcription.

Duchenne muscular dystrophy is a severe neuromuscular disease causing a progressive muscle wasting due to mutations in the DMD gene that lead to the absence of dystrophin protein. Adeno-associated virus (AAV)-based therapies aiming to restore dystrophin in muscles, by either exon skipping or microdystrophin expression, are very promising. However, the absence of dystrophin induces cellular perturbations that hinder AAV therapy efficiency. We focused here on the impact of the necrosis-regeneration process leading to nuclear centralization in myofiber, a common feature of human myopathies, on AAV transduction efficiency. We generated centronucleated myofibers by cardiotoxin injection in wild-type muscles prior to AAV injection. Intramuscular injections of AAV1 vectors show that transgene expression was drastically reduced in regenerated muscles, even when the AAV injection occurred 10 months post-regeneration. We show also that AAV genomes were not lost from cardiotoxin regenerated muscle and were properly localised in the myofiber nuclei but were less transcribed leading to muscle transduction defect. A similar defect was observed in muscles of the DMD mouse model mdx. Therefore, the regeneration process per se could participate to the AAV-mediated transduction defect observed in dystrophic muscles which may limit AAV-based therapies.

Acute Coronary Syndrome in the Era of SARS-CoV-2 Infection: A Registry of the French Group of Acute Cardiac Care.

BACKGROUND: In this study, we aimed to report clinical characteristics and outcomes of patients with and without SARS-CoV-2 infection who were referred for acute coronary syndrome (ACS) during the peak of the pandemic in France. METHODS: We included all consecutive patients referred for ST-elevation myocardial infarction (STEMI) or non-STEMI (NSTEMI) during the first 3 weeks of April 2020 in 5 university hospitals (Paris, south, and north of France), all performing primary percutaneous coronary intervention. RESULTS: The study included 237 patients (67 ± 14 years old; 69% male), 116 (49%) with STEMI and 121 (51%) with NSTEMI. The prevalence of SARS-CoV-2-associated ACS was 11% (n = 26) and 11 patients had severe hypoxemia on presentation (mechanical ventilation or nasal oxygen > 6 L/min). Patients were comparable regarding medical history and risk factors, except a higher prevalence of diabetes mellitus in SARS-CoV-2 patients (53.8% vs 25.6%; P = 0.003). In SARS-CoV-2 patients, cardiac arrest on admission was more frequent (26.9% vs 6.6%; P < 0.001). The presence of significant coronary artery disease and culprit artery occlusion in SARS-CoV-2 patients respectively, was 92% and 69.4% for those with STEMI, and 50% and 15.5% for those with NSTEMI. Percutaneous coronary intervention was performed in the same percentage of STEMI (84.6%) and NSTEMI (84.8%) patients, regardless of SARS-CoV-2 infection, but no-reflow (19.2% vs 3.3%; P < 0.001) was greater in SARS-CoV-2 patients. In-hospital death occurred in 7 SARS-CoV-2 patients (5 from cardiac cause) and was higher compared with noninfected patients (26.9% vs 6.2%; P < 0.001). CONCLUSIONS: In this registry, ACS in SARS-CoV-2 patients presented with high a percentage of cardiac arrest on admission, high incidence of no-reflow, and high in-hospital mortality.

CONTEXTE: Notre étude avait pour but d'établir les caractéristiques cliniques et les résultats de patients infectés ou non par le SRAS-CoV-2 qui ont été orientés en raison d'un syndrome coronarien aigu (SCA) pendant la phase aiguë de la pandémie en France. MÉTHODOLOGIE: Nous avons inclus dans l'étude tous les patients consécutifs qui ont présenté un infarctus du myocarde avec sus-décalage du segment ST (STEMI) ou sans sus-décalage du segment ST (NSTEMI) au cours des 3 premières semaines d'avril 2020 et qui ont été orientés vers 5 hôpitaux universitaires (situés à Paris, ainsi que dans le sud et le nord de la France), tous en mesure de réaliser des interventions co-ronariennes percutanées primaires. RÉSULTATS: L'étude comprenait 237 patients (âge : 67 ± 14 ans; proportion d'hommes : 69 %); 116 (49 %) présentaient un STEMI et 121 (51 %), un NSTEMI. La prévalence d'un SCA associé à une infection par le SRAS-CoV-2 s'établissait à 11 % (n = 26), et 11 patients étaient en hypoxémie grave (nécessitant une ventilation artificielle ou l'administration d'oxygène par voie nasale à un débit de plus de 6 l/min) à leur arrivée. Les patients présentaient des antécédents médicaux et des facteurs de risque comparables, à l'exception du fait que la prévalence du diabète était plus élevée chez les patients infectés par le SRAS-CoV-2 (53,8 % vs 25,6 %; p = 0,003). Ces derniers avaient plus souvent subi un arrêt cardiaque à leur admission (26,9 % vs 6,6 %; p < 0,001). Chez les patients infectés par le SRAS-CoV-2, une coronaropathie importante et une occlusion de l'artère coupable ont été observées chez respectivement 92 % et 69,4 % des patients présentant un STEMI, et chez 50 % et 15,5 % des patients présentant un NSTEMI. Une intervention coronarienne percutanée a été effectuée dans les mêmes proportions chez les patients subissant un STEMI (84,6 %) que chez ceux présentant un NSTEMI (84,8 %), sans égard à la présence ou à l'absence d'une infection par le SRAS-CoV-2, mais les cas de non-reperfusion (no-reflow) ont été plus fréquents chez les patients infectés que chez les autres patients (19,2 % et 3,3 %, respectivement; p < 0,001). Sept patients infectés par le SRAS-CoV-2 sont morts à l'hôpital (5 de cause cardiaque), ce qui représente un taux de mortalité plus élevé que chez les patients non infectés (26,9 % vs 6,2 %; p < 0,001). CONCLUSIONS: Dans le cadre de cette étude, le SCA survenu chez les patients infectés par le SRAS-CoV-2 était associé à un fort pourcentage d'arrêt cardiaque à l'admission, à une fréquence élevée de cas de non-reperfusion et à un taux élevé de mortalité hospitalière.

Mesalamine foam enema versus mesalamine liquid enema in active left-sided ulcerative colitis.

AIM: To determine in a noninferiority study whether mesalamine foam is as effective as mesalamine liquid enema for inducing clinical remission in patients with active left-sided ulcerative colitis (UC). METHODS: In a multicenter investigator-blind trial, 375 patients with mild-to-moderate UC were randomized to receive mesalamine foam 1 g/80 mL/day or mesalamine liquid enema 1 g/100 mL/day for 4 wk (W). Inclusion criteria were: disease extension at least 5 cm from anorectal junction and not above splenic flexure and Clinical Activity Index (CAI) 1-4 > or = 4. Primary end point was clinical remission at W4 defined as a CAI 1-4 < or = 2. Noninferiority of the foam to liquid enema was declared if the lower limit of the 97.5% unilateral confidence interval (97.5% CI) of the difference in remission rates between foam and liquid enema groups was greater than -15% . RESULTS: Remission rates at W4 in foam versus liquid were 68.3%versus 73.6% in per protocol (PP) population (lower limit of 97.5% CI -15.1%) and 66.7%versus 70.5% in intention-to-treat (ITT) population (97.5% CI -13.4%). Remission rates at W2 were 48.1 %versus 50.6% in ITT (97.5% CI -12.8%) and 49.1%versus 52.1% in PP (97.5% CI -13.8%) in foam versus liquid, respectively. Both treatments were well tolerated. CONCLUSIONS: A 4-wk treatment of 1 g mesalamine foam induced a clinical remission in 68% patients versus 73% with 1 g mesalamine liquid enema. Although the noninferiority of mesalamine foam could not be strictly demonstrated at W4 in the PP analysis, it was achieved in the ITT population and at W2 in both populations. Mesalamine foam represents a therapeutic alternative to mesalamine liquid enema in patients with mild-to-moderate active proctitis and proctosigmoiditis.

The effects of strontium ranelate on the risk of vertebral fracture in women with postmenopausal osteoporosis.

BACKGROUND: Osteoporotic structural damage and bone fragility result from reduced bone formation and increased bone resorption. In a phase 2 clinical trial, strontium ranelate, an orally active drug that dissociates bone remodeling by increasing bone formation and decreasing bone resorption, has been shown to reduce the risk of vertebral fractures and to increase bone mineral density. METHODS: To evaluate the efficacy of strontium ranelate in preventing vertebral fractures in a phase 3 trial, we randomly assigned 1649 postmenopausal women with osteoporosis (low bone mineral density) and at least one vertebral fracture to receive 2 g of oral strontium ranelate per day or placebo for three years. We gave calcium and vitamin D supplements to both groups before and during the study. Vertebral radiographs were obtained annually, and measurements of bone mineral density were performed every six months. RESULTS: New vertebral fractures occurred in fewer patients in the strontium ranelate group than in the placebo group, with a risk reduction of 49 percent in the first year of treatment and 41 percent during the three-year study period (relative risk, 0.59; 95 percent confidence interval, 0.48 to 0.73). Strontium ranelate increased bone mineral density at month 36 by 14.4 percent at the lumbar spine and 8.3 percent at the femoral neck (P<0.001 for both comparisons). There were no significant differences between the groups in the incidence of serious adverse events. CONCLUSIONS: Treatment of postmenopausal osteoporosis with strontium ranelate leads to early and sustained reductions in the risk of vertebral fractures.

Intravenous zoledronic acid in postmenopausal women with low bone mineral density.

BACKGROUND: Bisphosphonates are effective agents for the management of osteoporosis. Their low bioavailability and low potency necessitate frequent administration on an empty stomach, which may reduce compliance. Gastrointestinal intolerance limits maximal dosing. Although intermittent intravenous treatments have been used, the optimal doses and dosing interval have not been systematically explored. METHODS: We studied the effects of five regimens of zoledronic acid, the most potent bisphosphonate, on bone turnover and density in 351 postmenopausal women with low bone mineral density in a one-year, randomized, double-blind, placebo-controlled trial. Women received placebo or intravenous zoledronic acid in doses of 0.25 mg, 0.5 mg, or 1 mg at three-month intervals. In addition, one group received a total annual dose of 4 mg as a single dose, and another received two doses of 2 mg each, six months apart. Lumbar-spine bone mineral density was the primary end point. RESULTS: There were similar increases in bone mineral density in all the zoledronic acid groups to values for the spine that were 4.3 to 5.1 percent higher than those in the placebo group (P<0.001) and values for the femoral neck that were 3.1 to 3.5 percent higher than those in the placebo group (P<0.001). Biochemical markers of bone resorption were significantly suppressed throughout the study in all zoledronic acid groups. Myalgia and pyrexia occurred more commonly in the zoledronic acid groups, but treatment-related dropout rates were similar to that in the placebo group. CONCLUSIONS: Zoledronic acid infusions given at intervals of up to one year produce effects on bone turnover and bone density as great as those achieved with daily oral dosing with bisphosphonates with proven efficacy against fractures, suggesting that an annual infusion of zoledronic acid might be an effective treatment for postmenopausal osteoporosis.

Effects of oral alendronate on BMD in adult patients with osteogenesis imperfecta: a 3-year randomized placebo-controlled trial.

UNLABELLED: A 3-year, randomized, double-blind, placebo-controlled trial evaluated the effect of oral alendronate on the BMD of 64 adult patients with osteogenesis imperfecta. The mean increases in the lumbar spine BMD were 10.1 +/- 9.8% (p < 0.001) and 0.7 +/- 5.7% in the alendronate and placebo groups, respectively. Oral alendronate increases BMD in adult patients with osteogenesis imperfecta. INTRODUCTION: This study evaluated the effect of oral alendronate on the BMD of adult patients with osteogenesis imperfecta. MATERIALS AND METHODS: We carried out a 3-year, randomized, double-blind, placebo-controlled trial of oral alendronate in 64 adult patients with osteogenesis imperfecta. The primary endpoint was the difference between the groups in the mean percent change in lumbar spine BMD at 3 years. Secondary outcomes included changes in BMD of total hip, vertebral and peripheral fracture incidence, pain, hearing loss, and bone turnover biochemical markers. Patients were treated daily with either placebo or 10 mg alendronate. All received 1 g of calcium and 800 IU of vitamin D daily. RESULTS: The mean +/- SD increases in the lumbar spine BMD were 10.1 +/- 9.8% (p < 0.001) and 0.7 +/- 5.7% in the alendronate and placebo groups, respectively. Hip BMD increased in the alendronate group by 3.3 +/- 0.5% (p = 0.001) and decreased in the placebo group by 0.3 +/- 0.6%. The sample size was not sufficient to determine an effect of alendronate on fracture rate. A significant increase of the pain score was noted in the alendronate group (p = 0.04) in the intent-to-treat analysis but not in the per protocol analysis. There was no change in hearing in either group. Bone resorption and formation biochemical markers were significantly decreased in the alendronate group (p < 0.001). There were no differences in severe adverse effects between the groups, but there was an increase in nonsevere upper gastrointestinal effects in the alendronate group (p = 0.003). CONCLUSIONS: Oral alendronate increases BMD and increase nonsevere gastrointestinal adverse effects but does not modify the hearing loss in adult patients with osteogenesis imperfecta. More studies are needed to evaluate an effect on the fracture rate.

Vertebral fracture risk reduction with strontium ranelate in women with postmenopausal osteoporosis is independent of baseline risk factors.

UNLABELLED: Strontium ranelate (2 g/day) was studied in 5082 postmenopausal women. A reduction in incident vertebral fracture risk by 40% was shown after 3 years. This effect was independent of age, initial BMD, and prevalent vertebral fractures. INTRODUCTION: Strontium ranelate is an orally active treatment able to decrease the risk of vertebral and hip fractures in osteoporotic postmenopausal women. The aim of this study was to assess the efficacy of strontium ranelate according to the main determinants of vertebral fracture risk: age, baseline BMD, prevalent fractures, family history of osteoporosis, baseline BMI, and addiction to smoking. MATERIALS AND METHODS: We pooled data of two large multinational randomized double-blind studies with a population of 5082 (2536 receiving strontium ranelate 2 g/day and 2546 receiving a placebo), 74 years of age on average, and a 3-year follow-up. An intention-to-treat principle was used, as well as a Cox model for comparison and relative risks. RESULTS: The treatment decreased the risk of both vertebral (relative risk [RR] = 0.60 [0.53-0.69] p < 0.001) and nonvertebral (RR = 0.85 [0.74-0.99] p = 0.03) fractures. The decrease in risk of vertebral fractures was 37% (p = 0.003) in women <70 years, 42% (p < 0.001) for those 70-80 years of age, and 32% (p = 0.013) for those > or = 80 years. The RR of vertebral fracture was 0.28 (0.07-0.99) in osteopenic and 0.61 (0.53-0.70) in osteoporotic women, and baseline BMD was not a determinant of efficacy. The incidence of vertebral fractures in the placebo group increased with the number of prevalent vertebral fractures, but this was not a determinant of the effect of strontium ranelate. In 2605 patients, the risk of experiencing a first vertebral fracture was reduced by 48% (p < 0.001). The risk of experiencing a second vertebral fracture was reduced by 45% (p < 0.001; 1100 patients). Moreover, the risk of experiencing more than two vertebral fractures was reduced by 33% (p < 0.001; 1365 patients). Family history of osteoporosis, baseline BMI, and addiction to smoking were not determinants of efficacy. CONCLUSIONS: This study shows that a 3-year treatment with strontium ranelate leads to antivertebral fracture efficacy in postmenopausal women independently of baseline osteoporotic risk factors.

Long-term strontium ranelate administration in monkeys preserves characteristics of bone mineral crystals and degree of mineralization of bone.

UNLABELLED: In monkeys, long-term strontium ranelate administration results in a dose-dependent bone strontium uptake (mainly into newly formed bone) that preserves the degree of mineralization of bone and the bone mineral at the crystal level, showing its safety at bone mineral level. INTRODUCTION: Strontium ranelate simultaneously increases bone formation and decreases bone resorption, leading to prevention of bone loss and increase in bone mass and bone strength in normal and ovariectomized rats. This study investigated the interactions of stable strontium (Sr) with bone mineral in monkeys after long-term strontium ranelate treatment and after a period of treatment withdrawal. MATERIALS AND METHODS: Iliac bone was obtained from untreated monkeys, monkeys at the end of a 52-week strontium ranelate administration (200, 500, 1250 mg/kg/day orally), and in parallel groups 10 weeks after the end of strontium ranelate administration (same three doses; n = 3-7). Sr uptake and distribution in bone mineral were quantified by X-ray microanalysis, changes at the crystal level by X-ray diffraction, and the degree of mineralization of bone (DMB) by quantitative microradiography. RESULTS: After strontium ranelate administration, dose-dependent Sr uptake occurred into cortical and cancellous bone, with higher content (1.6 times) in new than in old bone. This Sr uptake decreased (50%) 10 weeks after treatment withdrawal; the decrease occurred almost exclusively in new bone. At the end of strontium ranelate treatment and after its withdrawal, a preservation of crystal characteristics was observed, suggesting that Sr was only faintly linked to crystals by ionic substitution and of DMB. CONCLUSIONS: These results show the absence of a deleterious effect of long-term strontium ranelate treatment on bone mineralization, confirming the histomorphometric observations made in postmenopausal osteoporotic women treated with strontium ranelate.

Differential effects of teriparatide and alendronate on bone remodeling in postmenopausal women assessed by histomorphometric parameters.

UNLABELLED: An 18-month randomized double-blind study was conducted in postmenopausal women with osteoporosis to compare the effects of once-daily teriparatide 20 microg with alendronate 10 mg on bone histomorphometry. Biopsies were obtained from 42 patients. Indices of bone formation were significantly higher after 6 or 18 months of teriparatide compared with alendronate treatment. INTRODUCTION: Alendronate and teriparatide increased BMD, assessed by DXA, by different mechanisms of action, supported by changes in biochemical markers of bone turnover. The purpose of this cross-sectional study was to explore the differential effects of these two osteoporosis treatments at the bone tissue level by examining bone histomorphometric parameters of bone turnover after either 6 or 18 months of treatment. MATERIALS AND METHODS: Patients were a cohort from a randomized parallel double-blind study conducted to compare the effects of once-daily teriparatide 20 microg and alendronate 10 mg in postmenopausal women with osteoporosis. Transiliac crest bone biopsies were obtained after tetracycline double labeling from 42 patients treated for 6 months (n = 23) or 18 months (n = 14); 5 additional patients were biopsied from contralateral sides at 6 and 18 months. Biopsy specimens adequate for quantitative analysis were analyzed by 2D histomorphometry from 17 patients at 6 months (teriparatide, n = 8; alendronate, n = 9) and 15 patients at 18 months (teriparatide, n = 8; alendronate, n = 7). Data were analyzed by two-sample tests. RESULTS: Histomorphometric indices of bone formation were significantly and markedly greater in the teriparatide group than in the alendronate group at 6 and 18 months, whereas indices of bone resorption were only significantly greater in the teriparatide group than in the alendronate group at 6 months. Bone formation and activation frequency were significantly lower at 18 months compared with 6 months in the teriparatide group, returning to levels comparable with untreated postmenopausal women. In the teriparatide group, the peak in histomorphometric bone formation indices coincided with peak levels for N-terminal propeptide of type I collagen, a biochemical marker of bone formation. The degree of mineralization was lower at 18 months than at 6 months with treatment in both groups but was not different between groups. CONCLUSIONS: These results confirm the opposite mechanisms of action of teriparatide and alendronate on bone remodeling and confirm the bone formation effect of teriparatide.

Predictive value of BMD for hip and other fractures.

UNLABELLED: The relationship between BMD and fracture risk was estimated in a meta-analysis of data from 12 cohort studies of approximately 39,000 men and women. Low hip BMD was an important predictor of fracture risk. The prediction of hip fracture with hip BMD also depended on age and z score. INTRODUCTION: The aim of this study was to quantify the relationship between BMD and fracture risk and examine the effect of age, sex, time since measurement, and initial BMD value. MATERIALS AND METHODS: We studied 9891 men and 29,082 women from 12 cohorts comprising EVOS/EPOS, EPIDOS, OFELY, CaMos, Rochester, Sheffield, Rotterdam, Kuopio, DOES, Hiroshima, and 2 cohorts from Gothenburg. Cohorts were followed for up to 16.3 years and a total of 168,366 person-years. The effect of BMD on fracture risk was examined using a Poisson model in each cohort and each sex separately. Results of the different studies were then merged using weighted coefficients. RESULTS: BMD measurement at the femoral neck with DXA was a strong predictor of hip fractures both in men and women with a similar predictive ability. At the age of 65 years, risk ratio increased by 2.94 (95% CI = 2.02-4.27) in men and by 2.88 (95% CI = 2.31-3.59) in women for each SD decrease in BMD. However, the effect was dependent on age, with a significantly higher gradient of risk at age 50 years than at age 80 years. Although the gradient of hip fracture risk decreased with age, the absolute risk still rose markedly with age. For any fracture and for any osteoporotic fracture, the gradient of risk was lower than for hip fractures. At the age of 65 years, the risk of osteoporotic fractures increased in men by 1.41 per SD decrease in BMD (95% CI = 1.33-1.51) and in women by 1.38 per SD (95% CI = 1.28-1.48). In contrast with hip fracture risk, the gradient of risk increased with age. For the prediction of any osteoporotic fracture (and any fracture), there was a higher gradient of risk the lower the BMD. At a z score of -4 SD, the risk gradient was 2.10 per SD (95% CI = 1.63-2.71) and at a z score of -1 SD, the risk was 1.73 per SD (95% CI = 1.59-1.89) in men and women combined. A similar but less pronounced and nonsignificant effect was observed for hip fractures. Data for ultrasound and peripheral measurements were available from three cohorts. The predictive ability of these devices was somewhat less than that of DXA measurements at the femoral neck by age, sex, and BMD value. CONCLUSIONS: We conclude that BMD is a risk factor for fracture of substantial importance and is similar in both sexes. Its validation on an international basis permits its use in case finding strategies. Its use should, however, take account of the variations in predictive value with age and BMD.

Influence of estrogen therapy at conventional and high doses on the degree of mineralization of iliac bone tissue: a quantitative microradiographic analysis in postmenopausal women.

The beneficial skeletal effects of menopausal estrogen replacement therapy (HRT) are well documented. The role of secondary mineralization of bone as a determinant of bone quality is now well established in postmenopausal women treated with bisphosphonates or SERMs. The aim of present study was to investigate the effect of conventional and high doses of estrogen on the main parameters reflecting the degree of mineralization of bone (DMB). Bone biopsies were obtained from 20 women with osteopenia or osteoporosis before and after 24 months (18 to 38 months) of conventional HRT, and from 19 women who had received high doses of estradiol (implant 100 mg every 3-6 months for 1.5-20 years). DMB parameters (mean DMB, DMB Freq. Max. and Heterogeneity Index of the individual distributions of DMB) were measured using quantitative microradiography in cortical, cancellous, and total bone and expressed as g mineral/cm(3) bone. Values obtained in women before HRT were lower than those reported in pre- and postmenopausal control women. After conventional HRT, there was an increase in mean DMB (total bone) of 4.4 +/- 1.9% (mean +/- SEM) versus pre-treatment values (4.1 +/- 2.1% in cortical bone, 4.5 +/- 2.3% in cancellous bone); these differences did not reach statistical significance (P = 0.055). Results were similar for DMB Freq. Max. but Heterogeneity Index was not significantly changed. After high dose estradiol therapy, mean DMB (total bone) was 6.9 +/- 1.9% higher than in untreated women (8.6 +/- 2.1% in cortical bone, 6.5 +/- 2.1% in cancellous bone); this difference was statistically significant (P