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1.
Org Biomol Chem ; 20(8): 1707-1722, 2022 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-35137752

RESUMEN

A simple covalent organic framework (COF) bearing ß-ketoenamine units as a potential heterogeneous ligand for ZnII-catalyzed fixation and transformation of CO2 into value-added chemicals is reported. Catalytic investigations convincingly demonstrated that the ZnII-functionalized covalent organic framework (Zn@TpTta) exhibits perfect catalytic activity in the fixation of CO2 for diverse epoxides with various substituents under sustainable conditions. A variety of terminal epoxides and slightly more complicated disubstituted epoxides were transformed into the corresponding cyclic carbonates with satisfactory to excellent yields (i.e., 69 to 99% yield) upon exposure to CO2 (1 atm) under solvent-free conditions (sustainable approach). On the other hand, this ZnII-loaded covalent organic framework also displayed excellent performance in facilitating atmospheric cyclizative CO2 capture, which led to the formation of diverse cyclic carbamates (i.e., 61 to 94% yield) from unsaturated amine systems using N-iodosuccinimide (NIS) as an iodinating agent and PEG-400 as a biodegradable and green polymeric solvent under base-free conditions (sustainable approach). The newly synthesized COF-based catalyst, namely, Zn@TpTta, has been completely characterized by SEM (scanning electron microscopy), EDX (energy dispersive X-ray analysis), HRTEM (high-resolution transmission electron microscopy), BET (Brunauer-Emmett-Teller), PXRD (powder X-ray diffraction), XPS (X-ray photoelectron spectroscopy), ICP (inductively coupled plasma), etc. More intriguingly, the catalytic system could be recycled over five times without a noticeable loss of catalytic performance for both reactions. This study opens an avenue for the Zn(II) embedded COF as a promising platform for regulating regioselectivity.

2.
Pharmacoepidemiol Drug Saf ; 31(1): 46-54, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34227170

RESUMEN

BACKGROUND: Comparative-effectiveness studies using real-world data (RWD) can be susceptible to surveillance bias. In solid tumor oncology studies, analyses of endpoints such as progression-free survival (PFS) are based on progression events detected by imaging assessments. This study aimed to evaluate the potential bias introduced by differential imaging assessment frequency when using electronic health record (EHR)-derived data to investigate the comparative effectiveness of cancer therapies. METHODS: Using a nationwide de-identified EHR-derived database, we first analyzed imaging assessment frequency patterns in patients diagnosed with advanced non-small cell lung cancer (aNSCLC). We used those RWD inputs to develop a discrete event simulation model of two treatments where disease progression was the outcome and PFS was the endpoint. Using this model, we induced bias with differential imaging assessment timing and quantified its effect on observed versus true treatment effectiveness. We assessed percent bias in the estimated hazard ratio (HR). RESULTS: The frequency of assessments differed by cancer treatment types. In simulated comparative-effectiveness studies, PFS HRs estimated using real-world imaging assessment frequencies differed from the true HR by less than 10% in all scenarios (range: 0.4% to -9.6%). The greatest risk of biased effect estimates was found comparing treatments with widely different imaging frequencies, most exaggerated in disease settings where time to progression is very short. CONCLUSIONS: This study provided evidence that the frequency of imaging assessments to detect disease progression can differ by treatment type in real-world patients with cancer and may induce some bias in comparative-effectiveness studies in some situations.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Sesgo , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/epidemiología , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Supervivencia sin Progresión
3.
Cancers (Basel) ; 14(13)2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35804834

RESUMEN

A vast amount of real-world data, such as pathology reports and clinical notes, are captured as unstructured text in electronic health records (EHRs). However, this information is both difficult and costly to extract through human abstraction, especially when scaling to large datasets is needed. Fortunately, Natural Language Processing (NLP) and Machine Learning (ML) techniques provide promising solutions for a variety of information extraction tasks such as identifying a group of patients who have a specific diagnosis, share common characteristics, or show progression of a disease. However, using these ML-extracted data for research still introduces unique challenges in assessing validity and generalizability to different cohorts of interest. In order to enable effective and accurate use of ML-extracted real-world data (RWD) to support research and real-world evidence generation, we propose a research-centric evaluation framework for model developers, ML-extracted data users and other RWD stakeholders. This framework covers the fundamentals of evaluating RWD produced using ML methods to maximize the use of EHR data for research purposes.

4.
Cancer Epidemiol Biomarkers Prev ; 31(6): 1195-1201, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35027431

RESUMEN

BACKGROUND: Clinico-genomic databases favor inclusion of long-term survivors, leading to potentially biased overall survival (OS) analyses. Risk set adjustments relying on the independent delayed entry assumption may mitigate this bias. We aimed to determine whether this assumption is satisfied in a dataset of patients with advanced non-small cell lung cancer (aNSCLC), and to give guidance for clinico-genomic OS analyses when the assumption is not satisfied. METHODS: We analyzed the association of timing of next-generation sequencing (NGS) testing with real-world OS (rwOS) in patient data from a United States-based nationwide longitudinal deidentified electronic health records-derived database. Estimates of rwOS using risk set adjustment were compared with estimates computed with respect to all patients, regardless of NGS testing. RESULTS: The independent delayed entry assumption was not satisfied in this database, and later sequencing had a negative association with the hazard of death after sequencing. In a model adjusted for relevant characteristics, each month delay in sequencing was associated with a 2% increase in the hazard of death. However, until the median survival time, estimates of OS using risk set adjustment are similar to estimates computed for all patients, regardless of NGS testing. CONCLUSIONS: rwOS analyses in clinico-genomic databases should assess the independent delayed entry assumption. Comparisons versus broader population may be useful to evaluate the rwOS differences between calculations using risk set adjustment and patient cohorts where the bias relates to overrepresentation of long survivors. IMPACT: This study illustrates practices that can increase the interpretability of findings from OS analyses in clinico-genomic databases.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Genómica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Análisis de Supervivencia , Estados Unidos
5.
Contemp Clin Trials Commun ; 30: 101000, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36186544

RESUMEN

Background: Hybrid controlled trials with real-world data (RWD), where the control arm is composed of both trial and real-world patients, could facilitate research when the feasibility of randomized controlled trials (RCTs) is challenging and single-arm trials would provide insufficient information. Methods: We propose a frequentist two-step borrowing method to construct hybrid control arms. We use parameters informed by a completed randomized trial in metastatic triple-negative breast cancer to simulate the operating characteristics of dynamic and static borrowing methods, highlighting key trade-offs and analytic decisions in the design of hybrid studies. Results: Simulated data were generated under varying residual-bias assumptions (no bias: HRRWD = 1) and experimental treatment effects (target trial scenario: HRExp = 0.78). Under the target scenario with no residual bias, all borrowing methods achieved the desired 88% power, an improvement over the reference model (74% power) that does not borrow information externally. The effective number of external events tended to decrease with higher bias between RWD and RCT (i.e. HRRWD away from 1), and with weaker experimental treatment effects (i.e. HRExp closer to 1). All dynamic borrowing methods illustrated (but not the static power prior) cap the maximum Type 1 error over the residual-bias range considered. Our two-step model achieved comparable results for power, type 1 error, and effective number of external events borrowed compared to other borrowing methodologies. Conclusion: By pairing high-quality external data with rigorous simulations, researchers have the potential to design hybrid controlled trials that better meet the needs of patients and drug development.

6.
Contemp Clin Trials ; 107: 106436, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34000410

RESUMEN

In phase 1 dose escalation studies, dose limiting toxicities (DLTs) are defined as adverse events of concern occurring during a predefined time window after first dosing of patients. Standard dose escalation designs, such as the continual reassessment method (CRM), only utilize this binary DLT information. Thus, late-onset DLTs are usually not accounted for when CRM guiding the dose escalation and finally defining the maximum tolerated dose (MTD) of the drug, which brings safety concerns for patients. Previously, several extensions of CRMs, such as the time-to-event CRM (TITE-CRM), fractional CRM (fCRM) and the data augmented CRM (DA-CRM), have been proposed to handle this issue without prolonging trial duration. However, among the model-based designs, none of the designs have explicitly controlled the risk of overdosing as in the escalation with overdose control (EWOC) design. Here we propose a novel dose escalation with overdose control design using a two-parameter logistic regression model for the probability of DLT depending on the dose and a piecewise exponential model for the time to DLT distribution, which we call rolling-CRM design. A comprehensive simulation study has been conducted to compare the performance of the rolling-CRM design with other dose escalation designs. Of note, the trial duration is significantly shorter compared to traditional CRM designs. The proposed design also retains overdose control characteristics, but might require a larger sample size compared to traditional CRM designs.


Asunto(s)
Antineoplásicos , Ensayos Clínicos Fase I como Asunto , Neoplasias , Antineoplásicos/uso terapéutico , Ensayos Clínicos Fase I como Asunto/métodos , Simulación por Computador , Relación Dosis-Respuesta a Droga , Humanos , Dosis Máxima Tolerada , Neoplasias/tratamiento farmacológico , Proyectos de Investigación
7.
Chem Commun (Camb) ; 56(81): 12202-12205, 2020 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-32926027

RESUMEN

The present study describes the favourable construction of a crystalline covalent organic framework (COF) with exceptional surface area, tunable pore size and huge CO2 capture efficiency to facilitate a novel multicomponent cyclization by introducing CO2 into extremely reactive organic skeletons. In the presence of a catalytic Cu/CuxOy NP-loaded COF, several 2-bromo-3-alkylacrylic acids combined with several amine derivatives and CO2 (0.1 MPa) are converted to the desired oxazolidinediones in excellent yields (up to 96%) under alkali-free conditions and ambient temperature.

8.
Contemp Clin Trials ; 89: 105890, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31740427

RESUMEN

To reduce a clinical trial's cost and ethical risk to its enrollees, some oncology trial designers have suggested borrowing information from similar but already completed trials to reduce the number of patients needed for the current study. Motivated by competing drug therapies for lymphoma, we propose a Bayesian adaptive "platform" trial design that uses commensurate prior methods at interim analyses to borrow adaptively from the control group of an earlier-starting trial. The design adjusts the trial's randomization ratio in favor of the novel treatment when the interim posterior indicates commensurability of the two control groups. In this setting, our design can supplement a control arm with historical data, and randomize more new patients to the novel treatments. This design is both ethical and economical, since it shortens the process of introducing new treatments into the market, and any additional costs introduced by this design will be compensated by the savings in control arm sizes. Our approach performs well via simulation across settings with varying degrees of commensurability and true treatment effects, and compares favorably to an adaptive "all-or-nothing" approach in which the decision to pool or discard historical controls is based on a simple ad-hoc frequentist test at interim analysis. We also consider a three drug extension where a new imaginary intervention joins the platform, and show again that our procedure performs well via simulation.


Asunto(s)
Teorema de Bayes , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Proyectos de Investigación , Simulación por Computador , Grupos Control , Costos y Análisis de Costo , Ética en Investigación , Humanos , Modelos Estadísticos , Distribución Aleatoria
9.
Stat Biopharm Res ; 11(1): 67-78, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31435458

RESUMEN

Some clinical trialists, especially those working in rare or pediatric disease, have suggested borrowing information from similar but already-completed clinical trials. This paper begins with a case study in which relying solely on historical control information would have erroneously resulted in concluding a significant treatment effect. We then attempt to catalog situations where borrowing historical information may or may not be advisable using a series of carefully designed simulation studies. We use an MCMC-driven Bayesian hierarchical parametric survival modeling approach to analyze data from a sponsor's colorectal cancer study. We also apply these same models to simulated data comparing the effective historical sample size, bias, 95% credible interval widths, and empirical coverage probabilities across the simulated cases. We find that even after accounting for variations in study design, baseline characteristics, and standard-of-care improvement, our approach consistently identifies Bayesianly significant differences between the historical and concurrent controls under a range of priors on the degree of historical data borrowing. Our simulation studies are far from exhaustive, but inform the design of future trials. When the historical and current controls are not dissimilar, Bayesian methods can still moderate borrowing to a more appropriate level by adjusting for important covariates and adopting sensible priors.

10.
J Clin Oncol ; 23(16): 3706-12, 2005 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-15867200

RESUMEN

PURPOSE: Bevacizumab (Avastin; Genentech Inc, South San Francisco, CA), a recombinant, humanized anti-vascular endothelial growth factor monoclonal antibody that inhibits tumor angiogenesis, has demonstrated survival benefit in patients with previously untreated metastatic colorectal cancer when combined with irinotecan/fluorouracil (FU)/leucovorin (LV; IFL). Three randomized clinical studies have evaluated bevacizumab in combination with FU/LV alone. A combined analysis of raw data from these studies was performed to better assess the efficacy of bevacizumab with FU/LV. PATIENTS AND METHODS: The analysis used primary efficacy data from three independent studies, including 241 patients in a combined control group receiving either FU/LV or IFL and 249 patients receiving FU/LV/bevacizumab (5 mg/kg once every 2 weeks). The efficacy data included response rate, progression-free survival, and overall survival. RESULTS: The median duration of survival was 17.9 months in the FU/LV/bevacizumab group, compared with 14.6 months in the combined control group, corresponding to a hazard ratio for death of 0.74 (P = .008). The median duration of progression-free survival was 8.8 months in the FU/LV/bevacizumab group, compared with 5.6 months in the combined control group, corresponding to a hazard ratio for disease progression of 0.63 (P < or = .0001). The addition of bevacizumab also improved the response rate (34.1% v 24.5%; P = .019). CONCLUSION: The addition of bevacizumab to FU/LV provides a statistically significant and clinically relevant benefit to patients with previously untreated metastatic colorectal cancer.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales Humanizados , Bevacizumab , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/secundario , Supervivencia sin Enfermedad , Femenino , Fluorouracilo/administración & dosificación , Humanos , Leucovorina/administración & dosificación , Masculino , Persona de Mediana Edad , Placebos , Seguridad , Tasa de Supervivencia , Resultado del Tratamiento , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Factor A de Crecimiento Endotelial Vascular/inmunología
11.
Indian J Dermatol ; 61(1): 121, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26955137

RESUMEN

Dermatofibroma is a common benign fibrohistiocytic tumor and its diagnosis is easy when it presents classical clinicopathological features. However, a dermatofibroma may show a wide variety of clinicopathological variants and, therefore, the diagnosis may be difficult. The typical dermatofibroma generally occurs as a single or multiple firm reddish-brown nodules. We report here two atypical presentations of dermatofibroma - Atrophic dermatofibroma and keloidal presentation of dermatofibroma. Clinical dermal atrophy is a common phenomenon in dermatofibromas as demonstrated by the dimpling on lateral pressure. However, this feature is exaggerated in the atrophic variant of dermatofibroma. Atrophic dermatofibroma is defined by dermal atrophy of more than 50% of the lesion apart from the usual features of common dermatofibroma. The keloidal variant of dermatofibroma should not be overlooked as a simple keloid. The findings of keloidal change in dermatofibromas may support that trauma is a possible cause of dermatofibroma.

13.
Am J Psychiatry ; 162(4): 683-90, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15800139

RESUMEN

OBJECTIVE: This investigation examined whether raloxifene, a selective estrogen receptor modulator, affects the risk for Alzheimer's disease. METHOD: The Multiple Outcomes of Raloxifene Evaluation was a randomized, placebo-controlled trial among postmenopausal women with osteoporosis. The effect of raloxifene (60 or 120 mg/day) on vertebral fractures was the primary outcome. Development of mild cognitive impairment and dementia was a secondary outcome. Women were given clinical and cognitive evaluations at baseline and annually. After 3 years, among the 5,386 women enrolled at participating sites, those who had clinical symptoms of dementia or scored in the lowest 10th percentile on cognitive screening were evaluated by a blinded dementia specialist and had brain scans and laboratory tests to evaluate dementia etiology. Dementia was diagnosed by a blinded adjudication committee. RESULTS: Of the 5,386 women, 5,153 (95.7%) were classified as cognitively normal, 181 (3.4%) had mild cognitive impairment, and 52 (1.0%) had dementia, 36 with Alzheimer's disease. Compared to those taking placebo, women receiving 120 mg/day of raloxifene had a 33% lower risk of mild cognitive impairment (relative risk, 0.67; 95% confidence interval [CI], 0.46-0.98) and somewhat lower risks of Alzheimer's disease (relative risk=0.52, 95% CI=0.22-1.21) and any cognitive impairment (relative risk=0.73, 95% CI=0.53-1.01). Risks of mild cognitive impairment, Alzheimer's disease, and any impairment were not significantly different in the group taking 60 mg/day of raloxifene. CONCLUSIONS: Raloxifene at a dose of 120 mg/day, but not 60 mg/day, resulted in reduced risk of cognitive impairment in postmenopausal women.


Asunto(s)
Trastornos del Conocimiento/prevención & control , Demencia/prevención & control , Osteoporosis Posmenopáusica/tratamiento farmacológico , Clorhidrato de Raloxifeno/uso terapéutico , Moduladores Selectivos de los Receptores de Estrógeno/uso terapéutico , Anciano , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/prevención & control , Enfermedad de Alzheimer/psicología , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/epidemiología , Comorbilidad , Demencia/diagnóstico , Demencia/epidemiología , Femenino , Evaluación Geriátrica , Humanos , Osteoporosis Posmenopáusica/epidemiología , Osteoporosis Posmenopáusica/psicología , Placebos , Escalas de Valoración Psiquiátrica , Medición de Riesgo , Índice de Severidad de la Enfermedad , Fracturas de la Columna Vertebral/prevención & control , Resultado del Tratamiento
14.
Arch Intern Med ; 162(10): 1140-3, 2002 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-12020184

RESUMEN

BACKGROUND: Raloxifene hydrochloride therapy reduces the risk for vertebral fractures at 3 years, but the effects on clinical vertebral fractures in the first year are not known. METHODS: The Multiple Outcomes of Raloxifene Evaluation (MORE) Trial enrolled 7705 women with osteoporosis, defined by prevalent vertebral fractures and/or a bone mineral density (BMD) T score at or below -2.5, who were treated with placebo or raloxifene at a dosage of 60 or 120 mg/d for 3 years. New clinical vertebral fractures were defined as incident vertebral fractures associated with signs and symptoms suggestive of vertebral fractures, such as back pain, and were diagnosed by means of postbaseline adjudicated spinal radiographs. Scheduled spinal radiographs were obtained at baseline and at 2 and 3 years. In addition, unscheduled spinal radiographs were obtained in women who reported signs or symptoms suggestive of vertebral fracture, and these radiographs subsequently underwent adjudication. If an adjudicated fracture was identified, this was also considered a clinical fracture. RESULTS: At 1 year, raloxifene, 60 mg/d, decreased the risk for new clinical vertebral fractures by 68% (95% confidence interval [CI], 20%-87%) compared with placebo in the overall study population, and by 66% (95% CI, 23%-89%) in women with prevalent vertebral fractures, who are at greater risk for subsequent fracture. The risk for clinical vertebral fractures in the raloxifene, 60 mg/d, group was decreased by 46% (95% CI, 14%-66%) at 2 years and by 41% (95% CI, 17%-59%) at 3 years. The cumulative incidence of new clinical vertebral fractures was lower in the group receiving raloxifene, 60 mg/d, compared with placebo (P<.001). We found no significant differences in the risk reductions for clinical vertebral fractures between the raloxifene groups at 1, 2, or 3 years. CONCLUSION: The early risk reduction for new clinical vertebral fractures with 1 year of raloxifene treatment was similar to that reported with other antiresorptive agents.


Asunto(s)
Osteoporosis Posmenopáusica/tratamiento farmacológico , Clorhidrato de Raloxifeno/uso terapéutico , Moduladores Selectivos de los Receptores de Estrógeno/uso terapéutico , Fracturas de la Columna Vertebral/prevención & control , Anciano , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Incidencia , Recurrencia , Riesgo , Fracturas de la Columna Vertebral/epidemiología , Factores de Tiempo
15.
J Bone Miner Res ; 17(1): 1-10, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11771654

RESUMEN

Although low absolute values of bone mineral density (BMD) predict increased fracture risk in osteoporosis, it is not certain how well increases in BMD with antiresorptive therapy predict observed reductions in fracture risk. This work examines the relationships between changes in BMD after 1 year or 3 years of raloxifene or placebo therapy and the risk for new vertebral fractures at 3 years. In the Multiple Outcomes of Raloxifene Evaluation (MORE) trial, 7705 postmenopausal women with osteoporosis were randomized to placebo or raloxifene 60 mg/day or 120 mg/day. Relationships between baseline BMD and changes in BMD from baseline with the risk of new vertebral fractures were analyzed in this cohort using logistic regression models with the raloxifene doses pooled. As has been observed in other populations, women with the lowest baseline lumbar spine or femoral neck BMD in the MORE cohort had the greatest risk for vertebral fractures. Furthermore, for any percentage change, either increase or decrease in femoral neck or lumbar spine BMD at 1 year or 3 years, raloxifene-treated patients had a statistically significantly lower vertebral fracture risk compared with placebo-treated patients. The decrease in fracture risk with raloxifene was similar across the range of percentage change in femoral neck BMD observed at 3 years; patients receiving raloxifene had a 36% lower risk of vertebral fracture compared with those receiving placebo. At any percentage change in femoral neck and lumbar spine BMD observed at 1 year, raloxifene treatment decreased the risks of new vertebral fractures at 3 years by 38% and 41%, respectively. The logistic regression model showed that the percentage changes in BMD with raloxifene treatment accounted for 4% of the observed vertebral fracture risk reduction, and the other 96% of the risk reduction remains unexplained. The present data show that the measured BMD changes observed with raloxifene therapy are poor predictors of vertebral fracture risk reduction with raloxifene therapy.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Osteoporosis Posmenopáusica/tratamiento farmacológico , Clorhidrato de Raloxifeno/uso terapéutico , Moduladores Selectivos de los Receptores de Estrógeno/uso terapéutico , Fracturas de la Columna Vertebral/prevención & control , Anciano , Femenino , Cuello Femoral , Humanos , Vértebras Lumbares , Persona de Mediana Edad , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/metabolismo , Factores de Riesgo , Fracturas de la Columna Vertebral/etiología , Fracturas de la Columna Vertebral/metabolismo , Factores de Tiempo
16.
J Bone Miner Res ; 19(5): 764-72, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15068500

RESUMEN

UNLABELLED: Different risk factors may influence the effectiveness of osteoporosis therapies. The interaction of 30 baseline risk factors and the effectiveness of raloxifene in the MORE study were assessed. The efficacy of raloxifene in reducing vertebral fractures is largely independent of the presence of clinical risk factors for osteoporotic fractures. INTRODUCTION: The aim of this analysis was to determine the effect of different risk factors on the effectiveness of raloxifene to reduce vertebral fractures in the Multiple Outcomes of Raloxifene Evaluation (MORE) study using logistic regression models. MATERIALS AND METHODS: The association was assessed using univariate analyses and a multivariate model between 30 potential risk factors at baseline and the risk of vertebral fractures after 3 years in the placebo group, as well as the interaction of risk factors with raloxifene therapy (at a dose of 60 or 120 mg/day). RESULTS AND CONCLUSIONS: In the univariate analysis of the placebo group, after adjusting for baseline lumbar spine BMD (LS BMD), short stature (odds ratio [OR] = 1.18), age (OR = 1.38), years since menopause (OR = 1.38), impaired cognitive function, visuospatial capabilities (OR = 1.19), impaired musculoskeletal strength (OR = 1.23), low femoral neck BMD (OR = 1.21), and prior vertebral fracture (OR = 4.95) were significantly associated with the incidence of new vertebral fractures. In the univariate analysis, significant interactions were observed between raloxifene treatment and age (p = 0.04), serum triglycerides (p = 0.03), LS BMD (p = 0.08), and diabetes mellitus (p = 0.04). In the multivariate analysis, the effectiveness of raloxifene was independent of almost all risk factors, with the exception of baseline serum triglyceride level and LS BMD, suggesting an increased efficacy of raloxifene in patients with increased triglyceride levels (p = 0.006) and lower LS BMD values (p = 0.008) at baseline. These data suggest that the efficacy of raloxifene in reducing vertebral fractures is largely independent of the presence of clinical risk factors for osteoporotic fractures.


Asunto(s)
Osteoporosis Posmenopáusica/tratamiento farmacológico , Clorhidrato de Raloxifeno/uso terapéutico , Moduladores Selectivos de los Receptores de Estrógeno/uso terapéutico , Fracturas de la Columna Vertebral/prevención & control , Análisis de Varianza , Densidad Ósea , Estudios de Evaluación como Asunto , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/efectos de los fármacos , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/metabolismo , Estudios Prospectivos , Radiografía , Factores de Riesgo , Fracturas de la Columna Vertebral/etiología , Fracturas de la Columna Vertebral/metabolismo , Resultado del Tratamiento , Triglicéridos/sangre
17.
J Bone Miner Res ; 19(3): 394-401, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15040827

RESUMEN

UNLABELLED: The change in BMD is a poor predictor of vertebral fracture risk after raloxifene treatment. One-year percent change in bone turnover and BMD was used to predict vertebral fracture risk. The percent change in osteocalcin was determined to be a better predictor of vertebral fracture risk than BMD. INTRODUCTION: The association between baseline BMD and fracture risk is well understood. However, the relationship between changes in BMD and fracture risk is not well defined. It has previously been demonstrated that BMD change was a poor predictor of vertebral fracture risk in raloxifene-treated women, whereas bone turnover markers were significantly associated with fracture risk. In the current analysis, we explore the prediction of vertebral fracture risk using changes in both BMD and bone turnover. MATERIALS AND METHODS: The Multiple Outcomes of Raloxifene Evaluation (MORE) trial was a randomized, placebo-controlled trial of 7705 women with osteoporosis treated with raloxifene 60 or 120 mg/day for 3 years. Markers of bone turnover were measured in one-third of the study population (n = 2503), and the present analyses include these women. Logistic regression models were constructed using one-year percent changes in BMD and bone turnover and relevant baseline demographics to predict the risk of vertebral fracture with pooled raloxifene therapy at 3 years. All covariates were standardized before modeling to facilitate direct comparisons between changes in BMD and bone turnover. RESULTS AND CONCLUSION: Prevalent vertebral fracture status (p < 0.0001), baseline lumbar spine BMD (p < 0.0001), and number of years postmenopausal (p = 0.0005) were independent predictors of fracture risk in raloxifene-treated patients. Therapy-by-change in femoral neck BMD (p = 0.02) and therapy-by-change in osteocalcin (OC; p = 0.01) were also significant for all treatment groups, indicating that changes in BMD and OC have different effects on fracture risk for the placebo and pooled raloxifene groups. The final model included significant baseline variables and change in OC (p = 0.01), whereas change in femoral neck BMD was not significant. After adjustment of each significant baseline variable, the percent change in OC was better able to predict the reduction in vertebral fracture risk than the percent change in femoral neck BMD in patients treated with raloxifene.


Asunto(s)
Densidad Ósea , Remodelación Ósea , Clorhidrato de Raloxifeno/uso terapéutico , Fracturas de la Columna Vertebral/epidemiología , Anciano , Biomarcadores/sangre , Biomarcadores/orina , Femenino , Cuello Femoral/diagnóstico por imagen , Cuello Femoral/lesiones , Humanos , Persona de Mediana Edad , Osteoporosis/tratamiento farmacológico , Prevalencia , Radiografía , Factores de Riesgo
18.
J Clin Endocrinol Metab ; 87(8): 3609-17, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12161484

RESUMEN

The Multiple Outcomes of Raloxifene Evaluation trial studied 7705 postmenopausal women with osteoporosis randomized to placebo, or raloxifene 60 or 120 mg/d [JAMA 282(1999): 637]. This report assesses the efficacy of raloxifene on the long-term cumulative incidence new vertebral fractures through 4 yr. New vertebral fractures was assessed from radiographs taken at baseline, yr 2-4. The primary analysis was the cumulative incidence of new vertebral fractures through 4 yr. A posthoc analysis compared the vertebral fracture risk in yr 4 alone with that observed in the first 3 yr. The 4-yr cumulative relative risks (RR) for one or more new vertebral fractures were 0.64 [95% confidence interval (CI) 0.53, 0.76] with raloxifene 60 mg/d and 0.57 (95% CI 0.48, 0.69) with raloxifene 120 mg/d. In yr 4 alone, raloxifene 60 mg/d reduced the new vertebral fracture risk by 39% [RR 0.61 (95% CI 0.43, 0.88)], which was not found to be significantly different from the RR observed in the first 3 yr in both raloxifene groups, irrespective of prevalent fracture status. The nonvertebral fracture risk was not significantly reduced [RR 0.93 (95% CI 0.81, 1.06)]. The safety profile after 4 yr was similar to that observed after 3 yr. Raloxifene 60 and 120 mg/d through 4 yr decreased the cumulative risk of new vertebral fractures in postmenopausal women with osteoporosis. The decreased vertebral fracture risk in yr 4 alone was not different from that observed in the first 3 yr.


Asunto(s)
Antagonistas de Estrógenos/administración & dosificación , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis Posmenopáusica/epidemiología , Clorhidrato de Raloxifeno/administración & dosificación , Fracturas de la Columna Vertebral/epidemiología , Anciano , Densidad Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Huesos/metabolismo , Antagonistas de Estrógenos/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Persona de Mediana Edad , Posmenopausia , Clorhidrato de Raloxifeno/efectos adversos , Factores de Riesgo , Fracturas de la Columna Vertebral/prevención & control , Resultado del Tratamiento
19.
Bone ; 33(3): 293-300, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-13678769

RESUMEN

Raloxifene reduces vertebral fracture risk in postmenopausal women with osteoporosis and established osteoporosis, but its efficacy in women with osteopenia has not been studied. The objective of this study was to evaluate the effect of raloxifene hydrochloride on the risk of vertebral fractures in postmenopausal women with osteopenia and to compare this effect with that in women with osteoporosis as defined by the bone mineral density (BMD) T-score at the hip. We studied the 3204 postmenopausal women with osteopenia or osteoporosis without vertebral fractures at baseline in the Multiple Outcomes of Raloxifene Evaluation trial. Compared with placebo, 60 mg/day raloxifene reduced the risk of new vertebral fractures at 3 years independent of baseline total hip BMD. The relative risk for new vertebral fractures for the raloxifene group compared with placebo was 0.53 (95% CI, 0.32-0.88) for those with osteopenia and 0.31 (0.06-0.71) for those with osteoporosis. In raloxifene-treated women the rate of vertebral fracture was similar in women with osteoporosis (2%) to that in women with osteopenia (1.9%). For clinically apparent vertebral fractures, the relative risk of fracture in the osteopenia group for raloxifene was 0.25 (0.04-0.63) compared with placebo. There were no new clinical vertebral fractures in women with osteoporosis receiving raloxifene, whereas four occurred in the placebo group. We conclude that treatment with 60 mg/day raloxifene significantly decreases the risk of new vertebral fractures and new clinical vertebral fractures in postmenopausal women without baseline vertebral fracture who have osteopenia or osteoporosis.


Asunto(s)
Enfermedades Óseas Metabólicas/tratamiento farmacológico , Antagonistas de Estrógenos/uso terapéutico , Osteoporosis Posmenopáusica/tratamiento farmacológico , Clorhidrato de Raloxifeno/uso terapéutico , Fracturas de la Columna Vertebral/prevención & control , Anciano , Densidad Ósea , Enfermedades Óseas Metabólicas/epidemiología , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/epidemiología , Posmenopausia , Factores de Riesgo , Conducta de Reducción del Riesgo , Fracturas de la Columna Vertebral/epidemiología , Resultado del Tratamiento
20.
Obstet Gynecol ; 104(4): 837-44, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15458908

RESUMEN

OBJECTIVE: To examine the effect of raloxifene on major adverse events that occur with postmenopausal estrogen therapy or tamoxifen. METHODS: The Multiple Outcomes of Raloxifene Evaluation, a multicenter, randomized, double-blind trial, enrolled 7,705 postmenopausal women with osteoporosis. Women were randomly assigned to raloxifene 60 mg/d or 120 mg/d or placebo. Outcomes included venous thromboembolism, cataracts, gallbladder disease, and endometrial hyperplasia or cancer. RESULTS: During a mean follow-up of 3.3 years, raloxifene was associated with an increased risk for venous thromboembolism (relative risk [RR] 2.1; 95% confidence interval [CI] 1.2-3.8). The excess event rate was 1.8 per 1,000 woman-years (95% CI -0.5-4.1), and the number needed to treat to cause 1 event was 170 (95% CI 100-582) over 3.3 years. Risk in the raloxifene group was higher than in the placebo group for the first 2 years, but decreased to about the same rate as in the placebo group thereafter. Raloxifene did not increase risk for cataracts (RR 0.9; 95% CI 0.8-1.1), gallbladder disease (RR 1.0; 95% CI 0.7-1.3), endometrial hyperplasia (RR 1.3; 95% CI 0.4-5.1), or endometrial cancer (RR 0.9; 95% CI 0.3-2.7). CONCLUSION: Raloxifene was associated with an increased risk for venous thromboembolism, but there was no increased risk for cataracts, gallbladder disease, endometrial hyperplasia, or endometrial cancer. LEVEL OF EVIDENCE: I


Asunto(s)
Osteoporosis Posmenopáusica/tratamiento farmacológico , Clorhidrato de Raloxifeno/efectos adversos , Moduladores Selectivos de los Receptores de Estrógeno/efectos adversos , Trombosis de la Vena/inducido químicamente , Trombosis de la Vena/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Femenino , Humanos , Incidencia , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Clorhidrato de Raloxifeno/uso terapéutico , Moduladores Selectivos de los Receptores de Estrógeno/uso terapéutico , Estados Unidos/epidemiología
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