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1.
Am J Transplant ; 13(11): 2989-95, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24011291

RESUMEN

It has been suggested that the number of exception model for end-stage liver disease (MELD) points for hepatocellular carcinoma (HCC) overestimates mortality risk. Average MELD at transplant, a measure of organ availability, correlates with mortality on an intent-to-treat basis and varies by donation service area (DSA). We analyzed Scientific Registry of Transplant Recipients data from 2005 to 2010, comparing transplant and death parameters for patients transplanted with HCC exception points to patients without HCC diagnosis (non-HCC), to determine whether the two groups were impacted differentially by DSA organ availability. HCC candidates are transplanted at higher rates than non-HCC candidates and are less likely to die on the waitlist. Overall risk of death trends downward by 1% per MELD point (p = 0.65) for HCC, but increases by 7% for non-HCC patients (p < 0.0001). The difference in the change of mortality with MELD is statistically significant between HCC and non-HCC candidates p < 0.0001. Posttransplant risk of death trends downward by 2% per MELD point (p = 0.28) for HCC patients, but increases by 3% per MELD point in non-HCC patients (p = 0.027), with the difference being statistically significant with p < 0.005. In summary, increasing wait time impacts HCC candidates less than non-HCC candidates and under increased competition for donor organs, HCC candidates' advantage increases.


Asunto(s)
Carcinoma Hepatocelular/cirugía , Enfermedad Hepática en Estado Terminal/cirugía , Neoplasias Hepáticas/cirugía , Trasplante de Hígado , Selección de Paciente , Donantes de Tejidos/provisión & distribución , Obtención de Tejidos y Órganos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/mortalidad , Enfermedad Hepática en Estado Terminal/diagnóstico , Enfermedad Hepática en Estado Terminal/mortalidad , Femenino , Geografía , Accesibilidad a los Servicios de Salud , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Tasa de Supervivencia , Factores de Tiempo , Listas de Espera/mortalidad
2.
Curr Alzheimer Res ; 8(3): 313-22, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21524270

RESUMEN

Mutations in the presenilin genes cause the majority of early-onset familial Alzheimer's disease. Recently, presenilin mutations have been identified in patients with dilated cardiomyopathy (DCM), a common cause of heart failure and the most prevalent diagnosis in cardiac transplantation patients. However, the molecular mechanisms, by which presenilin mutations lead to either AD or DCM, are not yet understood. We have employed transgenic Drosophila models and optical coherence tomography imaging technology to analyze cardiac function in live adult Drosophila. Silencing of Drosophila ortholog of presenilins (dPsn) led to significantly reduced heart rate and remarkably age-dependent increase in end-diastolic vertical dimensions. In contrast, overexpression of dPsn increased heart rate. Either overexpression or silencing of dPsn resulted in irregular heartbeat rhythms accompanied by cardiomyofibril defects and mitochondrial impairment. The calcium channel receptor activities in cardiac cells were quantitatively determined via real-time RT-PCR. Silencing of dPsn elevated dIP3R expression, and reduced dSERCA expression; overexprerssion of dPsn led to reduced dRyR expression. Moreover, overexpression of dPsn in wing disc resulted in loss of wing phenotype and reduced expression of wingless. Our data provide novel evidence that changes in presenilin level leads to cardiac dysfunction, owing to aberrant calcium channel receptor activities and disrupted Wnt signaling transduction, indicating a pathogenic role for presenilin mutations in DCM pathogenesis.


Asunto(s)
Cardiomiopatías/genética , Cardiomiopatías/fisiopatología , Drosophila melanogaster/genética , Presenilinas/genética , Enfermedad de Alzheimer/genética , Animales , Animales Modificados Genéticamente , Western Blotting , Canales de Calcio/genética , Canales de Calcio/metabolismo , Proteínas de Drosophila/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Tomografía de Coherencia Óptica , Vía de Señalización Wnt/genética
3.
Neurology ; 61(4): 456-64, 2003 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-12939417

RESUMEN

OBJECTIVE: To determine if long-term topiramate therapy is safe and slows disease progression in patients with ALS. METHODS: A double-blind, placebo-controlled, multicenter randomized clinical trial was conducted. Participants with ALS (n = 296) were randomized (2:1) to receive topiramate (maximum tolerated dose up to 800 mg/day) or placebo for 12 months. The primary outcome measure was the rate of change in upper extremity motor function as measured by the maximum voluntary isometric contraction (MVIC) strength of eight arm muscle groups. Secondary endpoints included safety and the rate of decline of forced vital capacity (FVC), grip strength, ALS functional rating scale (ALSFRS), and survival. RESULTS: Patients treated with topiramate showed a faster decrease in arm strength (33.3%) during 12 months (0.0997 vs 0.0748 unit decline/month, p = 0.012). Topiramate did not significantly alter the decline in FVC and ALSFRS or affect survival. Topiramate was associated with an increased frequency of anorexia, depression, diarrhea, ecchymosis, nausea, kidney calculus, paresthesia, taste perversion, thinking abnormalities, weight loss, and abnormal blood clotting (pulmonary embolism and deep venous thrombosis). CONCLUSIONS: At the dose studied, topiramate did not have a beneficial effect for patients with ALS. High-dose topiramate treatment was associated with a faster rate of decline in muscle strength as measured by MVIC and with an increased risk for several adverse events in patients with ALS. Given the lack of efficacy and large number of adverse effects, further studies of topiramate at a dose of 800 mg or maximum tolerated dose up to 800 mg/day are not warranted.


Asunto(s)
Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Fructosa/análogos & derivados , Fructosa/uso terapéutico , Adulto , Anciano , Esclerosis Amiotrófica Lateral/mortalidad , Progresión de la Enfermedad , Método Doble Ciego , Femenino , Fructosa/efectos adversos , Fructosa/farmacología , Fuerza de la Mano , Humanos , Tablas de Vida , Masculino , Persona de Mediana Edad , Contracción Muscular/efectos de los fármacos , Modelos de Riesgos Proporcionales , Seguridad , Análisis de Supervivencia , Tromboembolia/inducido químicamente , Topiramato , Insuficiencia del Tratamiento , Capacidad Vital/efectos de los fármacos
4.
Transplantation ; 72(6): 1066-72, 2001 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-11579302

RESUMEN

BACKGROUND: Recent studies suggest an association between diabetes mellitus and hepatitis C virus (HCV) infection. Our aim was to determine (1) the prevalence and determinants of new onset posttransplant diabetes mellitus (PTDM) in HCV (+) liver transplant (OLT) recipients, (2) the temporal relationship between recurrent allograft hepatitis and the onset of PTDM, and (3) the effects of antiviral therapy on glycemic control. METHODS: Between January of 1991 and December of 1998, of 185 OLTs performed in 176 adult patients, 47 HCV (+) cases and 111 HCV (-) controls were analyzed. We reviewed and analyzed the demographics, etiology of liver failure, pretransplant alcohol abuse, prevalence of diabetes mellitus, and clinical characteristics of both groups. In HCV (+) patients, the development of recurrent allograft hepatitis and its therapy were also studied in detail. RESULTS: The prevalence of pretransplant diabetes was similar in the two groups, whereas the prevalence of PTDM was significantly higher in HCV (+) than in HCV (-) patients (64% vs. 28%, P=0.0001). By multivariate analysis, HCV infection (hazard ratio 2.5, P=0.001) and methylprednisolone boluses (hazard ratio 1.09 per bolus, P=0.02) were found to be independent risk factors for the development of PTDM. Development of PTDM was found to be an independent risk factor for mortality (hazard ratio 3.67, P<0.0001). The cumulative mortality in HCV (+) PTDM (+) versus HCV (+) PTDM (-) patients was 56% vs. 14% (P=0.001). In HCV (+) patients with PTDM, we could identify two groups based on the temporal relationship between the allograft hepatitis and the onset of PTDM: 13 patients developed PTDM either before or in the absence of hepatitis (group A), and 12 concurrently with the diagnosis of hepatitis (group B). In gr. B, 11 of 12 patients received antiviral therapy. Normalization of liver function tests with improvement in viremia was achieved in 4 of 11 patients, who also demonstrated a marked improvement in their glycemic control. CONCLUSION: We found a high prevalence of PTDM in HCV (+) recipients. PTDM after OLT was associated with significantly increased mortality. HCV infection and methylprednisolone boluses were found to be independent risk factors for the development of PTDM. In approximately half of the HCV (+) patients with PTDM, the onset of PTDM was related to the recurrence of allograft hepatitis. Improvement in glycemic control was achieved in the patients who responded to antiviral therapy.


Asunto(s)
Diabetes Mellitus/etiología , Trasplante de Hígado/efectos adversos , Antivirales/uso terapéutico , Complicaciones de la Diabetes , Diabetes Mellitus/mortalidad , Diabetes Mellitus/fisiopatología , Femenino , Glucocorticoides/efectos adversos , Hepatitis C/complicaciones , Hepatitis C/tratamiento farmacológico , Hepatitis C/fisiopatología , Humanos , Masculino , Metilprednisolona/efectos adversos , Persona de Mediana Edad , Prevalencia , Recurrencia , Factores de Riesgo , Factores de Tiempo
5.
Biometrics ; 57(3): 972-4, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11550952

RESUMEN

This article describes a simple algorithm for calculating probabilities associated with group sequential trials. This allows the choice of boundaries that may not be among those implemented in available software.


Asunto(s)
Algoritmos , Biometría , Ensayos Clínicos como Asunto/estadística & datos numéricos , Humanos , Cetoconazol/uso terapéutico , Inutilidad Médica , Probabilidad , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Programas Informáticos , Insuficiencia del Tratamiento
6.
N Engl J Med ; 345(13): 948-55, 2001 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-11575286

RESUMEN

BACKGROUND: Treatment with a gonadotropin-releasing hormone agonist decreases bone mineral density and increases the risk of fracture in men with prostate cancer. We conducted a controlled study of the prevention of osteoporosis in men undergoing treatment with a gonadotropin-releasing hormone agonist. METHODS: In a 48-week, open-label study, we randomly assigned 47 men with advanced or recurrent prostate cancer and no bone metastases to receive either leuprolide alone or leuprolide and pamidronate (60 mg intravenously every 12 weeks). Bone mineral density of the lumbar spine and the proximal femur was measured by dual-energy x-ray absorptiometry. Trabecular bone mineral density of the lumbar spine was measured by quantitative computed tomography. Forty-one men completed the study. RESULTS: In men treated with leuprolide alone, the mean (+/-SE) bone mineral density decreased by 3.3+/-0.7 percent in the lumbar spine, 2.1+/-0.6 percent in the trochanter, and 1.8+/-0.4 percent in the total hip, and the mean trabecular bone mineral density of the lumbar spine decreased by 8.5+/-1.8 percent (P<0.001 for each comparison with the base-line value). In contrast, the mean bone mineral density did not change significantly at any skeletal site in men treated with both leuprolide and pamidronate. There were significant differences between the two groups in the mean changes in bone mineral density at 48 weeks in the lumbar spine (P<0.001), trochanter (P = 0.003), total hip (P=0.005), and trabecular bone of the lumbar spine (P=0.02). CONCLUSIONS: Pamidronate prevents bone loss in the hip and lumbar spine in men receiving treatment for prostate cancer with a gonadotropin-releasing hormone agonist.


Asunto(s)
Antineoplásicos Hormonales/efectos adversos , Densidad Ósea/efectos de los fármacos , Difosfonatos/uso terapéutico , Hormona Liberadora de Gonadotropina/agonistas , Leuprolida/efectos adversos , Osteoporosis/prevención & control , Neoplasias de la Próstata/tratamiento farmacológico , Anciano , Antineoplásicos Hormonales/uso terapéutico , Resorción Ósea/inducido químicamente , Resorción Ósea/prevención & control , Difosfonatos/efectos adversos , Difosfonatos/farmacología , Fémur/efectos de los fármacos , Humanos , Leuprolida/uso terapéutico , Vértebras Lumbares/efectos de los fármacos , Masculino , Osteocalcina/sangre , Osteoporosis/inducido químicamente , Pamidronato , Huesos Pélvicos/efectos de los fármacos , Neoplasias de la Próstata/fisiopatología
7.
J Clin Endocrinol Metab ; 86(8): 3654-8, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11502792

RESUMEN

Androstenedione is a steroid hormone and the major precursor to testosterone. It is available without prescription and taken with the expectation that it will be converted to testosterone endogenously and increase strength and athletic performance. The metabolism of orally administered testosterone has not been well studied. We randomly assigned 37 healthy men to receive 0, 100, or 300 mg oral androstenedione in a single daily dose for 7 d. Single 8-h urine collections were performed on the day before the start of the androstenedione administration and on d 1 and 7 to assess excretion rates of free and glucuronide- conjugated testosterone, androsterone, etiocholanolone, and dihydrotestosterone. Serum testosterone glucuronide concentrations were measured by frequent blood sampling over 8 h on d 1 in 16 subjects (5 each in the 0 and 100 mg group and 6 in the 300 mg group). In the control group, mean (+/-SE) d 1 and 7 excretion rates for testosterone, androsterone, etiocholanolone, and dihydrotestosterone were 3 +/- 1, 215 +/- 26, 175 +/- 26, and 0.4 +/- 0.1 microg/h, respectively. In the 100 mg group, mean d 1 and 7 excretion rates for testosterone, androsterone, etiocholanolone, and dihydrotestosterone were 47 +/- 11, 3,836 +/- 458, 4,306 +/- 458, and 1.6 +/- 0.2 microg/h, respectively. In the 300 mg group, mean d 1 and 7 excretion rates for testosterone, androsterone, etiocholanolone, and dihydrotestosterone were 115 +/- 39, 8,142 +/- 1,362, 10,070 +/- 1,999, and 7.7 +/- 1.5 microg/h, respectively. Urinary excretion rates of all metabolites were greater in both the 100 and 300 mg groups than in controls (P < 0.0001). Urinary excretion rates of testosterone (P = 0.007), androsterone (P = 0.009), etiocholanolone (P = 0.0005), and dihydrotestosterone (P < 0.0001) were greater in the subjects who received 300 mg androstenedione than in those who received 100 mg. In the treated groups, excretion of free testosterone accounted for less than 0.1% of the total excreted testosterone measured. Serum testosterone glucuronide levels increased significantly during frequent blood sampling in both the 100 and 300 mg groups compared with controls (P = 0.0005 for the 100 mg group; P < 0.0001 for the 300 mg group). The net mean changes in area under the curve for serum testosterone glucuronide were -18 +/- 25%, 579 +/- 572%, and 1267 +/- 1675% in the groups receiving 0, 100, and 300 mg/d androstenedione, respectively. We conclude that the administration of both 100 and 300 mg androstenedione increases the excretion rates of conjugated testosterone, androsterone, etiocholanolone, and dihydrotestosterone and the serum levels of testosterone glucuronide in men. The magnitude of these increases is much greater than the changes observed in serum total testosterone concentrations. These findings demonstrate that orally administered androstenedione is largely metabolized to testosterone glucuronide and other androgen metabolites before release into the general circulation.


Asunto(s)
Androstenodiona/metabolismo , Administración Oral , Adulto , Androstenodiona/sangre , Androstenodiona/orina , Androsterona/orina , Pueblo Asiatico , Población Negra , Dihidrotestosterona/orina , Etiocolanolona/orina , Glucurónidos/sangre , Glucurónidos/orina , Humanos , Masculino , Testosterona/sangre , Testosterona/orina , Estados Unidos , Población Blanca
8.
J Clin Invest ; 108(1): 63-72, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11435458

RESUMEN

In NOD (nonobese diabetic) mice, a model of autoimmune diabetes, various immunomodulatory interventions prevent progression to diabetes. However, after hyperglycemia is established, such interventions rarely alter the course of disease or allow sustained engraftment of islet transplants. A proteasome defect in lymphoid cells of NOD mice impairs the presentation of self antigens and increases the susceptibility of these cells to TNF-alpha-induced apoptosis. Here, we examine the hypothesis that induction of TNF-alpha expression combined with reeducation of newly emerging T cells with self antigens can interrupt autoimmunity. Hyperglycemic NOD mice were treated with CFA to induce TNF-alpha expression and were exposed to functional complexes of MHC class I molecules and antigenic peptides either by repeated injection of MHC class I matched splenocytes or by transplantation of islets from nonautoimmune donors. Hyperglycemia was controlled in animals injected with splenocytes by administration of insulin or, more effectively, by implantation of encapsulated islets. These interventions reversed the established beta cell-directed autoimmunity and restored endogenous pancreatic islet function to such an extent that normoglycemia was maintained in up to 75% of animals after discontinuation of treatment and removal of islet transplants. A therapy aimed at the selective elimination of autoreactive cells and the reeducation of T cells, when combined with control of glycemia, is thus able to effect an apparent cure of established type 1 diabetes in the NOD mouse.


Asunto(s)
Autoantígenos/inmunología , Enfermedades Autoinmunes/terapia , Diabetes Mellitus Tipo 1/terapia , Refuerzo Inmunológico de Injertos/métodos , Supervivencia de Injerto/efectos de los fármacos , Trasplante de Islotes Pancreáticos , Ratones Endogámicos NOD/inmunología , Factor de Necrosis Tumoral alfa/fisiología , Traslado Adoptivo , Animales , Presentación de Antígeno , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/cirugía , Glucemia/análisis , Trasplante de Células , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/cirugía , Femenino , Adyuvante de Freund/uso terapéutico , Regulación de la Expresión Génica/efectos de los fármacos , Antígenos H-2/genética , Antígenos H-2/inmunología , Humanos , Insulina/metabolismo , Secreción de Insulina , Islotes Pancreáticos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Nefrectomía , Pancreatectomía , Estado Prediabético , Inducción de Remisión , Linfocitos T/trasplante , Donantes de Tejidos , Factor de Necrosis Tumoral alfa/biosíntesis , Factor de Necrosis Tumoral alfa/genética , Microglobulina beta-2/deficiencia , Microglobulina beta-2/genética
9.
Biometrics ; 57(1): 282-6, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11252611

RESUMEN

Acute respiratory distress syndrome (ARDS) is a life-threatening acute condition that sometimes follows pneumonia or surgery. Patients who recover and leave the hospital are considered to have been cured at the time they leave the hospital. These data differ from typical data in which cure is a possibility: death times are not observed for patients who are cured and cure times are observed and vary among patients. Here we apply a competing risks model to these data and show it to be equivalent to a mixture model, the more common approach for cure data. Further, we derive an estimator for the variance of the cumulative incidence function from the competing risks model, and thus for the cure rate, based on elementary calculations. We compare our variance estimator to Gray's (1988, Annals of Statistics 16, 1140-1154) estimator, which is based on counting process theory. We find our estimator to be slightly more accurate in small samples. We apply these results to data from an ARDS clinical trial.


Asunto(s)
Biometría , Modelos Estadísticos , Ensayos Clínicos como Asunto/estadística & datos numéricos , Humanos , Modelos Biológicos , Síndrome de Dificultad Respiratoria/mortalidad , Síndrome de Dificultad Respiratoria/terapia , Análisis de Supervivencia
10.
Biol Psychiatry ; 49(6): 553-5, 2001 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-11257241

RESUMEN

BACKGROUND: In this study we explored if laboratory-based cocaine administration to human subjects was associated with long-term adverse outcomes. METHODS: Twenty-one non--reatment seeking individuals with cocaine dependence were evaluated at baseline and again 5 and 10 months following cocaine infusion in a brain imaging study. Outcomes included computer-driven multidimensional clinical assessments and radioimmunoassay of hair. For comparison, identical data were collected from 19 cocaine-dependent subjects who did not receive the infusion. RESULTS: The infused and noninfused groups did not differ on frequency of cocaine use (corroborated by radioimmunoassay of hair), Addiction Severity Index drug composite score, or Hamilton Rating Scale for Depression score at both follow-up time points. In a time-related trend analysis, both groups showed significant reductions in frequency of cocaine use. CONCLUSIONS: Laboratory-based cocaine administration can be a safe paradigm even in individuals who are not engaged in treatment.


Asunto(s)
Trastornos Relacionados con Cocaína/epidemiología , Cocaína/análisis , Aceptación de la Atención de Salud , Anciano , Encéfalo/anatomía & histología , Encéfalo/metabolismo , Cocaína/administración & dosificación , Trastornos Relacionados con Cocaína/diagnóstico , Femenino , Estudios de Seguimiento , Cabello/química , Humanos , Incidencia , Infusiones Intravenosas , Imagen por Resonancia Magnética , Masculino , Estudios Prospectivos , Radioinmunoensayo , Índice de Severidad de la Enfermedad , Tiempo
11.
Clin Endocrinol (Oxf) ; 54(2): 183-8, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11207632

RESUMEN

OBJECTIVE: Because acromegaly is an uncommon disorder, epidemiological data regarding the demographics of the disease such as the prevalence of hypogonadism have been limited. In order to derive clinical and epidemiological information, including underlying hormonal factors, regarding hypogonadism in patients with acromegaly, we performed a pilot study designed to develop a multi-centre acromegaly patient registry. DESIGN AND MEASUREMENTS: Medical records of patients with acromegaly seen between 1976 and 1996 at three Institutions were reviewed, and data were entered into a database using a secure internet website. Hypogonadism was defined as amenorrhoea in women and testosterone deficiency in men. Subanalysis was performed in patients with microadenomas and women less than 50 years of age, to include women of reproductive age. RESULTS: Information was available on 363 patients, of whom 54% were women. The mean age at diagnosis was 41 +/- 13 years. In subjects less than 50 years of age, hypogonadism was present in 59%. Hyperprolactinaemia was present in 45% and 21% of hypogonadal and eugonadal patients of reproductive age, respectively (P = 0.0003). GH levels were higher in patients with hypogonadism (P = 0.03). In patients < 50 years of age with microadenomas, hypogonadism was present in nine of the 22 (41%) patients, including 55% of the women and 27% of the men (P = ns). Hyperprolactinaemia was present in three of the 10 and four of the 14 of microadenoma patients with hypogonadism and eugonadism, respectively. CONCLUSION: We developed a web-based acromegaly patient registry and used it to show that hypogonadism is a frequent consequence of acromegaly, even in patients with microadenomas, who are not at risk from hypopituitarism due to local mass effects. We also demonstrated that prolactin and GH hypersecretion contribute to the pathogenesis of hypogonadism in acromegaly, and that hypogonadism may occur in microadenoma patients even in the absence of hyperprolactinaemia.


Asunto(s)
Acromegalia/etiología , Adenoma/complicaciones , Hipogonadismo/etiología , Neoplasias Hipofisarias/complicaciones , Acromegalia/sangre , Adenoma/sangre , Adulto , Bases de Datos Factuales , Femenino , Hormona del Crecimiento/sangre , Humanos , Hipogonadismo/sangre , Masculino , Persona de Mediana Edad , Proyectos Piloto , Neoplasias Hipofisarias/sangre , Prevalencia , Prolactina/sangre , Sistema de Registros , Estudios Retrospectivos
12.
Arch Fam Med ; 9(7): 631-8, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10910311

RESUMEN

CONTEXT: National physician practices related to the clinical recognition and management of obesity are unknown. OBJECTIVES: To estimate national patterns of office-based, obesity-related practices and to determine the independent predictors of these practices. DESIGN: Serial cross-sectional surveys of physician office visits. SETTING: Ambulatory medical care in the United States. PATIENTS: We analyzed 55,858 adult physician office visits sampled in the 1995-1996 National Ambulatory Medical Care Surveys. Data from the Third National Health and Nutrition Examination Surveys, 1988-1994 were used to assess and, then, adjust for the underreporting of obesity. MAIN OUTCOME MEASURES: Reporting of obesity at office visits and physician counseling for weight loss, exercise, and diet among patients identified as obese. RESULTS: Physicians reported obesity in only 8.6% of 1995-1996 National Ambulatory Medical Care Surveys visits. The 22.7% prevalence rate of the Third National Health and Nutrition Examination Surveys, 1988-1994 suggests that physicians reported obesity in only 38% of their obese patients. Among visits by patients identified as obese, physicians frequently provided counseling for weight loss (35.5%), exercise (32.8%), and diet (41.5%). Adjusted for population prevalence; however, each service was provided to no more than one quarter of all obese patients. While patients with obesity-related comorbidities were treated more aggressively, in these patients, weight loss counseling occurred at only 52% of the visits. CONCLUSIONS: Specific interventions to address obesity are infrequent in visits to US physicians. Obesity is underreported and interventions are only moderately likely among patients identified as obese, even for those with serious obesity-related comorbidities.


Asunto(s)
Obesidad/diagnóstico , Obesidad/terapia , Pautas de la Práctica en Medicina , Adulto , Anciano , Consejo , Estudios Transversales , Recolección de Datos , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Obesidad/epidemiología , Factores de Riesgo , Estados Unidos
13.
Am J Psychiatry ; 157(6): 975-81, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10831479

RESUMEN

OBJECTIVE: The goal of this 5-year naturalistic study of patients treated with clozapine was to examine the incidence of treatment-emergent diabetes mellitus in relation to other factors, including weight gain, lipid abnormalities, age, clozapine dose, and treatment with valproate. METHOD: Data on age, gender, race, diagnosis, family history of diabetes, and age at clozapine initiation were collected from medical records of 82 outpatients with schizophrenia or schizoaffective disorder. Clozapine dose, data on use of valproate, and laboratory test results were recorded at 6-month intervals. RESULTS: The mean age at the time of clozapine initiation of the 82 patients was 36.4 years; 26.8% of the patients were women, and 91.5% were Caucasian. The mean baseline weight was 175.5 lb, and the mean body mass index was 26.9 kg/m(2). Thirty patients (36.6%) were diagnosed with diabetes during the 5-year follow-up. Weight gain, use of valproate, and total daily dose of clozapine were not significant risk factors for developing diabetes mellitus. Patients experienced significant weight gain that continued until approximately month 46 from initiation of clozapine. There was a nonsignificant increase in total serum cholesterol and a significant increase in serum triglycerides level. CONCLUSIONS: The results support the hypotheses that patients treated with clozapine experience significant weight gain and lipid abnormalities and appear to be at increased risk for developing diabetes.


Asunto(s)
Antipsicóticos/efectos adversos , Peso Corporal/efectos de los fármacos , Clozapina/efectos adversos , Diabetes Mellitus/inducido químicamente , Hipercolesterolemia/inducido químicamente , Adulto , Factores de Edad , Antipsicóticos/uso terapéutico , Índice de Masa Corporal , Colesterol/sangre , Clozapina/uso terapéutico , Diabetes Mellitus/epidemiología , Diabetes Mellitus/genética , Diabetes Mellitus Tipo 2/inducido químicamente , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/genética , Relación Dosis-Respuesta a Droga , Familia , Femenino , Predisposición Genética a la Enfermedad , Humanos , Hipercolesterolemia/epidemiología , Hipertrigliceridemia/inducido químicamente , Hipertrigliceridemia/epidemiología , Hipertrigliceridemia/genética , Incidencia , Masculino , Obesidad/inducido químicamente , Obesidad/epidemiología , Trastornos Psicóticos/tratamiento farmacológico , Factores de Riesgo , Esquizofrenia/tratamiento farmacológico , Triglicéridos/sangre , Ácido Valproico/uso terapéutico
14.
Liver Transpl ; 6(2): 185-90, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10719018

RESUMEN

Hepatitis C virus (HCV) infection is associated with mixed cryoglobulinemia and membranoproliferative glomerulonephritis. After orthotopic liver transplantation (OLT), isolated cases of HCV-associated mixed cryoglobulinemia have been reported. We determined the prevalence and clinical characteristics of mixed cryoglobulinemia in HCV-infected liver transplant recipients at our institution. Between January 1991 and February 1998, a total of 191 OLTs were performed in 178 patients. Among these transplant recipients, 53 patients (29.8%) had positive serological test results for HCV infection by second-generation enzyme-linked immunosorbent assay. We studied 31 HCV-positive (HCV+) and 21 HCV-negative (HCV-) transplant recipients (control group). Renal and liver function studies were performed, and cryoglobulin, rheumatoid factor, C3, C4, and serum HCV RNA levels and genotype were determined. Results were compared using unpaired Student's t-test for continuous variables and Fisher's exact test for categorical variables. Baseline characteristics were similar between the groups. Six patients in the HCV+ group (19%) had mixed cryoglobulins present at the time of evaluation compared with none in the HCV- group (P =. 036). The only parameter associated with cryoglobulins in the HCV+ group was rheumatoid factor (P <.01). In 3 HCV+ patients with cryoglobulins, extrarenal signs of cryoglobulinemia were present. Glomerulonephritis was found in 4 HCV+ patients. Two patients with purpura and cryoglobulinemia had reduced clinical manifestations after antiviral therapy. In conclusion, mixed cryoglobulinemia was found in approximately 20% of the HCV+ liver transplant recipients. The presence of purpura or glomerulonephritis suggests HCV-associated mixed cryoglobulinemia, a clinical syndrome that may respond favorably to antiviral therapy.


Asunto(s)
Crioglobulinemia/virología , Hepatitis C/complicaciones , Trasplante de Hígado/efectos adversos , Adulto , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Pruebas de Función Renal , Pruebas de Función Hepática , Trasplante de Hígado/inmunología , Masculino , Persona de Mediana Edad
15.
JAMA ; 283(6): 779-82, 2000 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-10683057

RESUMEN

CONTEXT: Androstenedione, a steroid hormone and the major precursor to testosterone, is available without prescription and is purported to increase strength and athletic performance. The hormonal effects of androstenedione, however, are unknown. OBJECTIVE: To determine if oral administration of androstenedione increases serum testosterone levels in healthy men. DESIGN: Open-label randomized controlled trial conducted between October 1998 and April 1999. SETTING: General clinical research center of a tertiary-care, university-affiliated hospital. PARTICIPANTS: Forty-two healthy men aged 20 to 40 years. INTERVENTION: Subjects were randomized to receive oral androstenedione (either 100 mg/d [n = 15] or 300 mg/d [n = 14]) or no androstenedione (n = 13) for 7 days. MAIN OUTCOME MEASURES: Changes in serum testosterone, androstenedione, estrone, and estradiol levels, measured by frequent blood sampling, compared among the 3 treatment groups. RESULTS: Mean (SE) changes in the area under the curve (AUC) for serum testosterone concentrations were -2% (7%), -4% (4%), and 34% (14%) in the groups receiving 0, 100, and 300 mg/d of androstenedione, respectively. When compared with the control group, the change in testosterone AUC was significant for the 300-mg/d group (P<.001) but not for the 100-mg/d group (P = .48). Baseline testosterone levels, drawn 24 hours after androstenedione administration, did not change. Mean (SE) changes in the AUC for serum estradiol concentrations were 4% (6%), 42% (12%), and 128% (24%) in the groups receiving 0, 100, and 300 mg/d of androstenedione, respectively. When compared with the control group, the change in the estradiol AUC was significant for both the 300-mg/d (P<.001) and 100-mg/d (P = .002) groups. There was marked variability in individual responses for all measured sex steroids. CONCLUSIONS: Our data suggest that oral androstenedione, when given in dosages of 300 mg/d, increases serum testosterone and estradiol concentrations in some healthy men.


Asunto(s)
Androstenodiona/farmacología , Testosterona/sangre , Administración Oral , Adulto , Androstenodiona/administración & dosificación , Androstenodiona/sangre , Área Bajo la Curva , Estradiol/sangre , Estrona/sangre , Humanos , Masculino , Testosterona/metabolismo
16.
JAMA ; 283(1): 69-73, 2000 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-10632282

RESUMEN

CONTEXT: Major advances in treatment of burn injuries in the last 20 years have made it possible to save the lives of children with massive burns, but whether their survival comes at the cost of impaired quality of life is unknown. OBJECTIVE: To investigate the long-term quality of life in children who have survived massive burns. DESIGN AND SETTING: Retrospective, cross-sectional study conducted in a regional pediatric burn center. PATIENTS: Eighty subjects who were younger than 18 years at the time of injury, who survived massive burns involving > or =70% of the body surface, and who were admitted to the burn center between 1969 and 1992 were evaluated an average (SD) of 14.7 (6.0) years after injury. MAIN OUTCOME MEASURES: Short Form 36 (SF-36) scores of the 60 patients aged at least 14 years were compared with national norms and the impact of clinical variables on individual domain scores was assessed. RESULTS: The SF-36 domain scores of the study patients, who had survived massive burns at a mean (SD) age of 8.8 (5.5) years, were generally similar to the normal population). However, 15% and 20% of the burn patients had scores in the physical functioning and physical role domains, respectively, that were more than 2 SDs below the relevant norm, indicating that a few patients had continuing serious physical disability. Better functional status of the family predicted a higher score in physical role (P = .04). The child's early reintegration with preburn activities predicted higher scores in general health (P = .03), physical functioning (P = .003), and physical role (P = .01). Children followed up consistently in the multidisciplinary burn clinic for 2 years had higher physical functioning (P = .04). CONCLUSIONS: In this study, while some children surviving severe burns had lingering physical disability, most had a satisfying quality of life. Comprehensive burn care that included experienced multidisciplinary aftercare played an important role in recovery.


Asunto(s)
Quemaduras/rehabilitación , Calidad de Vida , Sobrevivientes , Adulto , Niño , Costo de Enfermedad , Estudios Transversales , Personas con Discapacidad , Humanos , Salud Mental , Estudios Retrospectivos , Perfil de Impacto de Enfermedad
17.
Arch Neurol ; 57(1): 94-9, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10634454

RESUMEN

OBJECTIVE: To determine the efficacy of donepezil hydrochloride for the treatment of Alzheimer disease in patients drawn from clinical practice. DESIGN: Two-center, randomized, placebo-controlled, double-masked crossover study. SETTING: Memory disorders units at Massachusetts General and Brigham and Women's hospitals, Boston. PATIENTS: Sixty individuals (30 men and 30 women; mean +/- SD age, 75.0+/-9.5 years) with probable Alzheimer disease and scores of 20 or less on the information-memory-concentration subscale of the Blessed Dementia Scale. INTERVENTIONS: Placebo wash-in, followed in randomized sequence by (1) donepezil hydrochloride therapy, 5 mg/d, for 6 weeks, followed by placebo washout for 6 weeks and (2) placebo treatment for 6 weeks. PRIMARY OUTCOME MEASURE: Change in Alzheimer's Disease Assessment Scale cognitive subscale scores from the beginning to the end of the two 6-week treatment periods. RESULTS: Among patients completing treatment and testing for both periods (n = 48), subscale scores improved (mean +/- SEM) 2.17+/-0.98 points (95% confidence interval, 0.20-4.10 points) during donepezil therapy relative to placebo therapy (P = .04). Scores returned toward baseline within 3 weeks of drug washout. There was no associated change in caregiver-rated global impression (donepezil vs placebo: proportion improved, 0.24 vs 0.22; proportion worsened, 0.27 vs 0.35; P = .34) or on specific tests of explicit memory or verbal fluency. Contrary to studies with tacrine, the presence of the apolipoprotein E epsilon4 allele did not predict donepezil treatment failure. Most common adverse events related to donepezil therapy were nausea (5 patients), diarrhea (3 patients), and agitation (3 patients). Serious events possibly related to drug use were seizure, pancreatitis, and syncope (1 patient each). CONCLUSION: This independent confirmation of data from phase 3 trials suggests that donepezil therapy modestly improves cognition in patients with Alzheimer disease who are encountered in clinical practice.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Indanos/administración & dosificación , Nootrópicos/administración & dosificación , Piperidinas/administración & dosificación , Anciano , Anciano de 80 o más Años , Cognición/efectos de los fármacos , Estudios Cruzados , Donepezilo , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Masculino , Pruebas Neuropsicológicas , Resultado del Tratamiento
18.
Transpl Infect Dis ; 2(3): 112-7, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11429021

RESUMEN

BACKGROUND: Optimal prophylaxis against cytomegalovirus (CMV) disease for organ transplant patients at risk for primary infection (donor seropositive, recipient seronegative, D+R-) remains to be determined. We hypothesized that prolonged oral ganciclovir therapy following intravenous therapy would provide increased protection. METHODS: A total of 155 evaluable D+R- organ transplant recipients from 13 transplant centers were entered into the study: all received intravenous ganciclovir (5 mg/kg/day) for 5-10 days and then either oral acyclovir (400 mg tid) or oral ganciclovir (1 g tid) for an additional 12 weeks. Patients were assigned to their treatment groups at a central randomization site, with a separate randomization scheme for each of the organs transplanted (kidney, heart, or liver). In the case of kidney transplants, the patients were stratified according to source of the kidney (living related vs. cadaveric donor). The primary endpoint was the incidence of CMV disease in the first six months post-transplant. RESULTS: Treatment with oral ganciclovir was associated with a significant decrease in the incidence of symptomatic disease or viremia when compared with the oral acyclovir group (32% vs. 50%, P<0.05). This difference was most marked in terms of tissue invasive disease: only 3 of 15 symptomatic patients in the ganciclovir group vs. 10 of 21 in the acyclovir group developed tissue-invasive infection (P<0.05). There was a significant difference in the time to CMV disease or viremia in the two groups: mean time 212+/-17 days post-transplant for the acyclovir group vs. 291+/-13 days for the ganciclovir group (P<0.001). The incidence of allograft rejection was 34% in the ganciclovir group and 46% in the acyclovir group (P=NS). Leukopenia was more common in the ganciclovir group (P<0.05), but in no case did it require drug discontinuation. Ganciclovir resistance did not develop in this study. CONCLUSION: Prophylaxis with oral ganciclovir following a brief course of intravenous ganciclovir provides useful protection against primary CMV disease.


Asunto(s)
Aciclovir/uso terapéutico , Antivirales/uso terapéutico , Infecciones por Citomegalovirus/prevención & control , Ganciclovir/uso terapéutico , Trasplante de Corazón , Trasplante de Riñón , Trasplante de Hígado , Complicaciones Posoperatorias/virología , Aciclovir/administración & dosificación , Aciclovir/efectos adversos , Administración Oral , Adolescente , Adulto , Anciano , Antivirales/efectos adversos , Niño , Quimioterapia Combinada , Femenino , Ganciclovir/administración & dosificación , Ganciclovir/efectos adversos , Trasplante de Corazón/inmunología , Humanos , Terapia de Inmunosupresión/métodos , Inyecciones Intravenosas , Trasplante de Riñón/inmunología , Trasplante de Hígado/inmunología , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/prevención & control
19.
Stat Med ; 18(11): 1341-54, 1999 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-10399200

RESUMEN

Clinical trials often assess therapeutic benefit on the basis of an event such as death or the diagnosis of disease. Usually, there are several additional longitudinal measures of clinical status which are collected to be used in the treatment comparison. This paper proposes a simple non-parametric test which combines a time to event measure and a longitudinal measure so that a substantial treatment difference on either of the measures will reject the null hypothesis. The test is applied on AIDS prophylaxis and paediatric trials.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/mortalidad , Ensayos Clínicos como Asunto/estadística & datos numéricos , Resultado del Tratamiento , Fármacos Anti-VIH/uso terapéutico , Antiinfecciosos/uso terapéutico , Antifúngicos/uso terapéutico , Candidiasis/prevención & control , Niño , Preescolar , Clotrimazol/uso terapéutico , Dapsona/uso terapéutico , Didanosina/uso terapéutico , Quimioterapia Combinada , Fluconazol/uso terapéutico , Cabeza/crecimiento & desarrollo , Humanos , Estudios Longitudinales , Pentamidina/uso terapéutico , Neumonía por Pneumocystis/prevención & control , Estadísticas no Paramétricas , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Zidovudina/uso terapéutico
20.
J Clin Endocrinol Metab ; 84(6): 2151-6, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10372724

RESUMEN

Although a causal association between estrogen deficiency and bone loss has been established for many years, the mechanism by which estrogen deficiency leads to bone loss is unclear. Estrogen deficiency could induce bone loss either by a direct effect on bone cells to modify the production of bone-resorbing cytokines or by altering the production or response to calcium regulatory hormones such as PTH and 1,25-dihydroxyvitamin D. To assess the effects of ovarian hormones on calcium regulatory hormones, we evaluated the ability of calcium to suppress PTH secretion and the ability of PTH to increase serum 1,25-dihydroxyvitamin D and whole blood ionic calcium levels in women before and after GnRH analog-induced ovarian suppression. Sixteen women with endometriosis underwent i.v. infusion of calcium (1.1 mg calcium gluconate/cc in 5% dextrose) at a rate of 4 cc/kg x h (n = 7) or human PTH-(1-34) (Parathar) at a dose of 0.55 U/kg x h (n = 9) before and after 6 months of suppression of ovarian function with the GnRH analog nafarelin acetate (200 microg, intranasally, twice daily). Initial infusions were performed between days 6-10 of the menstrual cycle. Serum PTH and whole blood ionic calcium levels were measured at -20, -10, and 0 min and then every 10 min for 2 h during i.v. calcium infusions. Whole blood ionic calcium and 1,25-dihydroxyvitamin D levels were measured every 6 h for 24 h during i.v. human PTH-(1-34) infusions. Serum estradiol levels were markedly suppressed by nafarelin therapy in both groups of women. The relationship between whole blood ionic calcium and serum PTH levels was similar before and during nafarelin-induced ovarian suppression. The net change and rate of rise in serum 1,25-dihydroxyvitamin D levels in response to PTH infusion were similar before and during nafarelin therapy. Peak whole blood ionic calcium and incremental increases in ionic calcium in response to PTH were similar before and during nafarelin therapy. Our data suggest that ovarian suppression does not alter the regulation of PTH secretion in response to calcium, the ability of PTH to stimulate 1,25-dihydroxyvitamin D formation, or the skeletal sensitivity to PTH. These findings suggest that alterations in calcium regulatory hormones by estrogen deficiency are unlikely to play a major role in the pathogenesis of estrogen deficiency bone loss.


Asunto(s)
Ovario/efectos de los fármacos , Hormona Paratiroidea/metabolismo , Teriparatido/farmacología , Vitamina D/análogos & derivados , Adulto , Calcio/sangre , Gluconato de Calcio/farmacología , Estradiol/sangre , Femenino , Hormonas/farmacología , Humanos , Nafarelina/farmacología , Ovario/metabolismo , Fosfatos/sangre , Vitamina D/metabolismo
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