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1.
Am J Respir Crit Care Med ; 164(10 Pt 1): 1885-9, 2001 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11734441

RESUMEN

Sarcoidosis may be affected by sex, race, and age. A Case Control Etiologic Study of Sarcoidosis (ACCESS) enrolled 736 patients with sarcoidosis within 6 mo of diagnosis from 10 clinical centers in the United States. Using the ACCESS sarcoidosis assessment system, we determined organ involvement for the whole group and for subgroups differentiated by sex, race, and age (less than 40 yr or 40 yr and older). The study population was heterogeneous in terms of race (53% white, 44% black), sex (64% female, 36% male), and age (46% < 40 yr old, 54% > or = 40 yr old). Women were more likely to have eye and neurologic involvement (chi(2) = 4.74, p < 0.05 and chi(2) = 4.60, p < 0.05 respectively), have erythema nodosum (chi(2) = 7.28, p < 0.01), and to be age 40 yr or over (chi(2) = 6.07, p < 0.02) whereas men were more likely to be hypercalcemic (chi(2) = 7.38, p < 0.01). Black subjects were more likely to have skin involvement other than erythema nodosum (chi(2) = 5.47, p < 0.05), and eye (chi(2) = 13.8, p < 0.0001), liver (chi(2) = 23.3, p < 0.0001), bone marrow (chi(2) = 18.8, p < 0.001), and extrathoracic lymph node involvement (chi(2) = 7.21, p < 0.01). We conclude that the initial presentation of sarcoidosis is related to sex, race, and age.


Asunto(s)
Sarcoidosis/epidemiología , Sarcoidosis/patología , Adulto , Distribución por Edad , Factores de Edad , Anciano , Población Negra , Estudios de Casos y Controles , Disnea/etiología , Eritema Nudoso/etiología , Femenino , Volumen Espiratorio Forzado , Humanos , Hipercalcemia/etiología , Modelos Lineales , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Sarcoidosis/clasificación , Sarcoidosis/complicaciones , Índice de Severidad de la Enfermedad , Caracteres Sexuales , Distribución por Sexo , Estados Unidos/epidemiología , Capacidad Vital , Población Blanca
2.
Am J Respir Crit Care Med ; 164(11): 2085-91, 2001 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11739139

RESUMEN

Despite reports of familial clustering of sarcoidosis, little empirical evidence exists that disease risk in family members of sarcoidosis cases is greater than that in the general population. To address this question, we estimated sarcoidosis familial relative risk using data on disease occurrence in 10,862 first- and 17,047 second-degree relatives of 706 age, sex, race, and geographically matched cases and controls who participated in the multicenter ACCESS (A Case-Control Etiology Study of Sarcoidosis) study from 1996 to 1999. Familial relative risk estimates were calculated using a logistic regression technique that accounted for the dependence between relatives. Sibs had the highest relative risk (odds ratio [OR] = 5.8; 95% confidence interval [CI] = 2.1-15.9), followed by avuncular relationships (OR = 5.7; 95% CI = 1.6-20.7), grandparents (OR = 5.2; 95% CI = 1.5-18.0), and then parents (OR = 3.8; 95% CI = 1.2-11.3). In a multivariate model fit to the parents and sibs data, the familial relative risk adjusted for age, sex, relative class, and shared environment was 4.7 (95% CI = 2.3-9.7). White cases had a markedly higher familial relative risk compared with African-American cases (18.0 versus 2.8; p = 0.098). In summary, a significant elevated risk of sarcoidosis was observed among first- and second-degree relatives of sarcoidosis cases compared with relatives of matched control subjects.


Asunto(s)
Sarcoidosis/epidemiología , Sarcoidosis/genética , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Orden de Nacimiento , Población Negra/genética , Estudios de Casos y Controles , Niño , Análisis por Conglomerados , Femenino , Humanos , Incidencia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Linaje , Vigilancia de la Población , Modelos de Riesgos Proporcionales , Riesgo , Factores de Riesgo , Análisis de Supervivencia , Estados Unidos/epidemiología , Población Blanca/genética
3.
Circulation ; 104(22): 2660-5, 2001 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-11723015

RESUMEN

BACKGROUND: The Post Coronary Artery Bypass Graft Trial, designed to compare the effects of two lipid-lowering regimens and low-dose anticoagulation versus placebo on progression of atherosclerosis in saphenous vein grafts of patients who had had CABG surgery, demonstrated that aggressive lowering of LDL cholesterol levels to a mean yearly cholesterol level from 93 to 97 mg/dL compared with a moderate reduction to a level of 132 to 136 mg/dL decreased the progression of atherosclerosis in saphenous vein grafts. Low-dose anticoagulation did not affect progression. This secondary analysis tested the hypothesis that a similar decrease in progression of atherosclerosis would also be present in native coronary arteries as measured in the left main coronary artery (LMCA). METHODS AND RESULTS: A sample of 402 patients was randomly selected from 1102 patients who had baseline and follow-up views of the LMCA suitable for analysis. Patients treated with the aggressive lipid-lowering strategy had less progression of atherosclerosis in the LMCA as measured by changes in minimum (P=0.0003) lumen diameter or the maximum percent stenosis (P=0.001), or the presence of substantial progression (P=0.008), or vascular occlusion (P=0.005) when compared with the moderate strategy. CONCLUSIONS: A strategy of aggressive lipid lowering results in significantly less atherosclerosis progression than a moderate approach in LMCAs.


Asunto(s)
Anticolesterolemiantes/uso terapéutico , Puente de Arteria Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/terapia , Vasos Coronarios/efectos de los fármacos , Anticoagulantes/uso terapéutico , LDL-Colesterol/sangre , Resina de Colestiramina/uso terapéutico , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/sangre , Vasos Coronarios/cirugía , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Lípidos/sangre , Lovastatina/uso terapéutico , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Vena Safena/trasplante , Resultado del Tratamiento
4.
J Thromb Thrombolysis ; 11(2): 143-9, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11406729

RESUMEN

BACKGROUND: Since coronary artery bypass graft patients remain at risk of coronary artery and bypass graft occlusion after successful surgery, adjunct treatment regimens are under investigation. In a study of the patients of the multicenter Post Coronary Artery Bypass Graft (Post CABG) Trial, 1 mg warfarin was found to have no important effect on coagulation parameters. STUDY DESIGN: The effects of 1, 2 and 3 mg warfarin were evaluated at six-week intervals in 20 Post CABG Trial patients receiving titrated dose increases in comparison to 20 patients of similar age, gender and time from CABG treated with placebo. RESULTS: International normalized ratio (INR) values increased with warfarin dose increments for 1, 2, and 3 mg, respectively (0.95+/-0.16, 1.08+/-0.19, and 1.34+/-0.39) and in comparison to placebo treated patients (dosextreatment p<0.001). Factor VII coagulant activity decreased with warfarin titration (1 mg, 119.0+/-18.3 %; 2 mg, 100.6+/-32.8 %; 3 mg, 95.0+/-27.8 %) and in comparison to placebo (dosextreatment p=0.008). Levels of prothrombin fragment F1.2, tissue plasminogen activator, fibrinogen and von Willebrand factor were unchanged with warfarin dose increments and in comparison to placebo. CONCLUSIONS: At doses up to 3 mg, warfarin acts on the INR through a reduction of factor VII with no effect on the fibrinolytic system, fibrinogen or von Willebrand factor. At these doses F1.2 did not document reduced coagulation activity. The observations of this study were consistent with the decision in the Post CABG Trial to increase the warfarin dose above 1 mg to achieve a distinct effect of warfarin that was less than full anticoagulation.


Asunto(s)
Anticoagulantes/uso terapéutico , Puente de Arteria Coronaria , Enfermedad Coronaria/prevención & control , Oclusión de Injerto Vascular/prevención & control , Complicaciones Posoperatorias/prevención & control , Trombosis/prevención & control , Warfarina/uso terapéutico , Adulto , Anciano , Anticoagulantes/administración & dosificación , Anticoagulantes/efectos adversos , Aspirina/administración & dosificación , Aspirina/uso terapéutico , Enfermedad Coronaria/sangre , Enfermedad Coronaria/cirugía , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Factor VII/análisis , Femenino , Fibrinógeno/análisis , Humanos , Relación Normalizada Internacional , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/análisis , Hemorragia Posoperatoria/inducido químicamente , Protrombina/análisis , Recurrencia , Vena Safena/patología , Vena Safena/trasplante , Activador de Tejido Plasminógeno/análisis , Resultado del Tratamiento , Warfarina/administración & dosificación , Warfarina/efectos adversos , Factor de von Willebrand/análisis
5.
Circulation ; 102(2): 157-65, 2000 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-10889125

RESUMEN

BACKGROUND: The Post Coronary Artery Bypass Graft Trial, designed to compare the effects of 2 lipid-lowering regimens and low-dose anticoagulation versus placebo on progression of atherosclerosis in saphenous vein grafts of patients who had had CABG surgery, demonstrated that aggressive lowering of LDL cholesterol (LDL-C) levels to <100 mg/dL compared with a moderate reduction to 132 to 136 mg/dL decreased the progression of atherosclerosis in grafts. Low-dose anticoagulation did not significantly affect progression. METHODS AND RESULTS: Approximately 3 years after the last trial visit, Clinical Center Coordinators contacted each patient by telephone to ascertain the occurrence of cardiovascular events and procedures. The National Death Index was used to ascertain vital status for patients who could not be contacted. Vital status was established for all but 3 of 1351 patients. Information on nonfatal events was available for 95% of surviving patients. A 30% reduction in revascularization procedures and 24% reduction in a composite clinical end point were observed in patients assigned to aggressive strategy compared with patients assigned to moderate strategy during 7.5 years of follow-up, P=0. 0006 and 0.001, respectively. Reductions of 35% in deaths and 31% in deaths or myocardial infarctions with low-dose anticoagulation compared with placebo were also observed, P=0.008 and 0.003, respectively. CONCLUSIONS: -The long-term clinical benefit observed during extended follow-up in patients assigned to the aggressive strategy is consistent with the angiographic findings of delayed atherosclerosis progression in grafts observed during the trial. The apparent long-term benefit of low-dose warfarin remains unexplained.


Asunto(s)
Anticolesterolemiantes/administración & dosificación , Anticoagulantes/administración & dosificación , Puente de Arteria Coronaria , Enfermedad Coronaria/tratamiento farmacológico , Enfermedad Coronaria/cirugía , Warfarina/administración & dosificación , Adulto , Anciano , LDL-Colesterol/sangre , Enfermedad Coronaria/mortalidad , Método Doble Ciego , Estudios de Seguimiento , Humanos , Tablas de Vida , Persona de Mediana Edad , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/mortalidad , Infarto del Miocardio/cirugía , Resultado del Tratamiento
6.
Am J Hematol ; 64(1): 26-31, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10815784

RESUMEN

The Multicenter Study of Hydroxyurea in Sickle Cell Anemia (MSH) demonstrated the efficacy of hydroxyurea in reducing the rate of painful crises compared to placebo. We used resource utilization data collected in the MSH to determine the cost-effectiveness of hydroxyurea. The MSH was a randomized, placebo-controlled double-blind clinical trial involving 299 patients at 21 sites. The primary outcome, visit to a medical facility, was one of the criteria to define occurrence of painful crisis. Cost estimates were applied to all outpatient and emergency department visits and inpatient hospital stays that were classified as a crisis. Other resources for which cost estimates were applied included hospitalization for chest syndrome, analgesics received, hydroxyurea dosing, laboratory testing, and clinic visits for management of patient care. Annualized differential costs were calculated between hydroxyurea- and placebo-receiving patients. Hospitalization for painful crisis accounted for the majority of costs in both arms of the study, with an annual mean of $12,160 (95% CI: $9,440, $14,880) for hydroxyurea and $17,290 (95% CI: $13,010, $21,570) for placebo. The difference in means was $5,130 (95% CI: $60, $10,200; P = 0.048). Chest syndrome was the next largest cost with a mean difference of $830 (95% CI: $-340, $2,000; P = 0.16). The hydroxyurea arm was also associated with lower costs for emergency department visits, transfusion, and use of opiate analgesics. In total, the annual average cost per patient receiving hydroxyurea was $16,810 (95% CI: $13,350, $20,270) and the annual average costs per patient receiving placebo was $22,020 (95% CI: $17,340, $26,710). The difference in means was $5,210 (95% CI: $-610, $11,030; P = 0.21). The cost of hydroxyurea with the more intensive monitoring required when using this drug appears to be more than offset by decreased costs for medical care of painful crisis and analgesic use. Although the total cost difference was not significant statistically, these results suggest that hydroxyurea therapy is cost-effective compared to placebo in the management of adult patients with sickle cell anemia. If hydroxyurea can prevent development of chronic organ damage, long-term savings may be even greater.


Asunto(s)
Anemia de Células Falciformes/tratamiento farmacológico , Anemia de Células Falciformes/economía , Antidrepanocíticos/administración & dosificación , Análisis Costo-Beneficio , Hidroxiurea/administración & dosificación , Adulto , Antidrepanocíticos/economía , Método Doble Ciego , Femenino , Humanos , Hidroxiurea/economía , Masculino
7.
J Thromb Thrombolysis ; 7(3): 313-8, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10373714

RESUMEN

Although coronary bypass graft surgery has increased the survival and quality of life of many individuals, patients remain at risk of restenosis and thrombotic occlusion of the coronary arteries and bypass grafts. In the screening period for participation in the multicenter Post Coronary Artery Bypass Graft (Post CABG) trial, the effects of 1 mg daily warfarin were evaluated using paired patient samples collected prior to and after at least 21 days of treatment. In stable patients (n = 40; 39 males 1 female; 51-74 years old) who previously had undergone coronary artery revascularization (1-10 years), no alterations in prothrombin time, international normalized ratio (INR), prothrombin fragment 1.2, or the hemostatic risk factors factor VII antigen and coagulant activity, von Willebrand's factor, fibrinogen, tPA, or PAI-1 were associated with the 1 mg daily warfarin treatment. The observations reported here supported the Post CABG Studies Steering Committee decision to treat patients with 1-4 mg warfarin daily adjusted to achieve INRs not to exceed 2. 0 consistent with low-intensity therapy.


Asunto(s)
Anticoagulantes/administración & dosificación , Puente de Arteria Coronaria , Warfarina/administración & dosificación , Anciano , Anticoagulantes/uso terapéutico , Antígenos/análisis , Factor VII/análisis , Femenino , Fibrinógeno/análisis , Humanos , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/análisis , Inhibidor 1 de Activador Plasminogénico/sangre , Cuidados Posoperatorios , Protrombina/análisis , Tiempo de Protrombina , Fumar/sangre , Activador de Tejido Plasminógeno/análisis , Warfarina/uso terapéutico , Factor de von Willebrand/análisis
8.
Sarcoidosis Vasc Diffuse Lung Dis ; 16(1): 75-86, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10207945

RESUMEN

BACKGROUND: Sarcoidosis is a multiorgan granulomatous disease of unknown cause. Lack of an objective system for assessment of sarcoidosis to evaluate disease course and effectiveness of therapy is a major problem. METHODS: The sarcoidosis assessment instrument was developed by the Steering Committee of A Case Control Etiologic Study of Sarcoidosis (ACCESS) which included investigators at the ten ACCESS Clinical Centers, the Clinical Coordinating Center, and representatives of the National Heart, Blood, and Lung Institute. This system was developed to assess sarcoidosis organ involvement in ACCESS patients who would be followed over a two-year period. The system represents a consensus of opinions of members of the Steering Committee based on review of their experience and the medical literature. RESULTS: Criteria for involvement in patients with biopsy-confirmed sarcoidosis are presented for organs and systems that are commonly involved (lung, skin, eyes, liver, calcium metabolism), unusual but clinically important (nervous system, kidney, heart) and other sites (non-thoracic lymph nodes, bone marrow, spleen, bone/joint, ear/nose/throat, parotid/salivary glands, muscles). CONCLUSION: The proposed instrument is partially subjective in that it depends upon the clinician's diligence in pursuing evidence for sarcoidosis involvement of various organs. It is hoped that this instrument will lead to increased standardization in the definition of sarcoidosis organ involvement to help clinicians and researchers better characterize patients with sarcoidosis.


Asunto(s)
Enfermedades Óseas/patología , Oftalmopatías/patología , Enfermedades Gastrointestinales/patología , Sarcoidosis Pulmonar/patología , Sarcoidosis/patología , Enfermedades de la Piel/patología , Enfermedades Óseas/clasificación , Oftalmopatías/clasificación , Enfermedades Gastrointestinales/clasificación , Humanos , Reproducibilidad de los Resultados , Sarcoidosis/clasificación , Índice de Severidad de la Enfermedad , Enfermedades de la Piel/clasificación
9.
Transfusion ; 38(6): 522-9, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9661685

RESUMEN

BACKGROUND: The indications for transfusion have never been evaluated in an adequately sized clinical trial. A pilot study was conducted to plan larger clinical trials. STUDY DESIGN AND METHODS: Hip fracture patients undergoing surgical repair who had postoperative hemoglobin levels less than 10 g per dL were randomly assigned to receive 1) symptomatic transfusion: that is, transfusion for symptoms of anemia or for a hemoglobin level that dropped below 8 g per dL or 2) threshold transfusion: that is, patients receive 1 unit of packed RBCs at the time of random assignment and as much blood as necessary to keep the hemoglobin level above 10 g per dL. Outcomes were 60-day mortality, morbidity, functional status, and place of residence. RESULTS: Among 84 eligible patients enrolled, mean (+/- SD) prerandomization hemoglobin was 9.1 (+/- 0.6) g/ dL. The median number of units transfused in the threshold transfusion group was 2 (interquartile range, = 1-2), and that in the symptomatic transfusion group was 0 (6; interquartile range, = 0-2) (p < 0.001). Mean hemoglobin levels were approximately 1 g per dL higher in the threshold group than in the symptomatic group: for example, on Day 2, 10.3 (+/- 0.9) g per dL versus 9.3 (+/- 1.2) g per dL, respectively (p < 0.001). At 60 days, death or inability to walk across the room without assistance occurred in 16 (39.0%) of the symptomatic transfusion group and 19 (45.2%) of the threshold transfusion group. Death occurred by 60 days in 5 (11.9%) of the symptomatic transfusion group and 2 (4.8%) in the threshold transfusion group (relative risk = 2.5; 95% CI, 0.5-12.2). Other outcomes were similar for the two groups. CONCLUSIONS: Symptomatic transfusion may be an effective blood-sparing protocol associated with the transfusion of appreciably fewer units of RBCs and lower mean hemoglobin levels than are associated with the threshold transfusion policy. However, it is unknown whether these two clinical strategies have comparable mortality, morbidity, or functional status. A definitive trial is needed.


Asunto(s)
Transfusión de Eritrocitos , Hemoglobinas/metabolismo , Fracturas de Cadera/terapia , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Fracturas de Cadera/sangre , Fracturas de Cadera/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Resultado del Tratamiento
10.
Control Clin Trials ; 18(6): 500-5; discussion 514-6, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9408713

RESUMEN

Of the three most important approaches to evaluating lifestyle and health outcomes--observational studies, individual subject random assignment clinical trials, and community random assignment clinical trials--individual subject random assignment clinical trials provide the most useful information and the most certain inferences. Observational studies are limited by the collection of information on association of lifestyle instead of change in lifestyle with health outcomes, as well as by individual lifestyle selection that may be associated with particular outcomes. Community randomized trials may be the best way to decide such public health policy issues as whether or not to add fluoride to a water supply or to use a community-wide anti-smoking program. The limited amount of individual-specific data collected in community randomized trials, difficulties in accounting for missing data, and problems in data analysis because people move into or out of communities that are under study limit the value of community randomized trials for advising individuals whether or not to embark on a lifestyle modification program. Clinical trials of pharmacologic agents have successfully addressed challenges to individual subject random assignment clinical trials of lifestyle modification, such as long duration of study, access to study intervention(s) by individuals not assigned them, and cost.


Asunto(s)
Conductas Relacionadas con la Salud , Estilo de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Servicios de Salud Comunitaria , Humanos
11.
Control Clin Trials ; 18(5): 420-30, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9315425

RESUMEN

The Multicenter Study of Hydroxyurea in Sickle Cell Anemia (MSH), a double-blind randomized clinical trial, compared the frequency of acute vaso-occlusive (painful) crises during 2 yr of follow-up in 299 patients randomly assigned to hydroxyurea or placebo. Most patients had more than one crisis; all crises reported were included in the primary outcome analysis. A total of 7,229 follow-up medical contact reports were classified as crises/not crises by a Crisis Review Committee. Because of the time required to report, document, and classify contacts, interim analyses were prepared with incomplete data. If a stopping boundary were crossed, early termination could be advised only after assessing the potential impact of the incomplete data. In an extension of stochastic curtailment methods, simulation procedures were used to estimate the probability of detecting differences when group crisis rates projected to the end of the study were compared using a rank test. To account for medical contacts not yet reported and the future occurrence of crises, Poisson process models assuming no treatment effect on crisis rates were used for these simulations. The number of unclassified contacts that would be classified as crises was simulated as a binomial random variable. These methods may be useful for interim monitoring in other studies of recurrent events with ongoing event reporting and classification.


Asunto(s)
Anemia de Células Falciformes/tratamiento farmacológico , Antidrepanocíticos/uso terapéutico , Hidroxiurea/uso terapéutico , Procesos Estocásticos , Antidrepanocíticos/efectos adversos , Sesgo , Intervalos de Confianza , Recolección de Datos/estadística & datos numéricos , Método Doble Ciego , Estudios de Seguimiento , Humanos , Hidroxiurea/efectos adversos , Modelos Estadísticos , Resultado del Tratamiento
12.
Stroke ; 28(6): 1107-14, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9183334

RESUMEN

BACKGROUND AND PURPOSE: Ischemic cerebral infarction (CI) is a serious complication of acute myocardial infarction (MI). Little information exists on CI after thrombolytic therapy for MI. METHODS: Of 3924 MI patients treated with recombinant tissue plasminogen activator (rt-PA) and heparin, 29 (0.7%) developed CI after treatment. All CI patients had detailed neurological evaluations, and 27 (93%) had CT scans centrally reviewed. RESULTS: Age range was 40 to 74 years (mean, 60 years); 25 patients (86%) were men, and 22 (76%) were white. The electrocardiographic location of MI was anterior in 22 (76%) and nonanterior in 7 (24%). Five CIs occurred within 6 hours, 4 between 6 to 24 hours, 8 during the remainder of the first week, 10 during the second week, and 2 others distributed over the 4 weeks after study entry. Six of 29 CIs did not involve the cerebral cortex; 9 patients (31%) had multiple CIs. Of 28 CIs thought to be embolic in origin, 17 showed strong evidence for at least one cardiac abnormality (mural clot, wall-motion abnormality, aneurysm, or atrial fibrillation) known to be associated more specifically with embolism than MI. Eight of 27 CIs (30%) with CT scans had hemorrhagic transformation of varying degrees; 5 were symptomatic. CONCLUSIONS: The time of occurrence and sites of CI after rt-PA and heparin therapy for acute MI are similar to those reported during the prethrombolytic era.


Asunto(s)
Infarto Cerebral/inducido químicamente , Heparina/efectos adversos , Infarto del Miocardio/tratamiento farmacológico , Terapia Trombolítica/efectos adversos , Activador de Tejido Plasminógeno/efectos adversos , Adulto , Anciano , Hemorragia Cerebral/inducido químicamente , Infarto Cerebral/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Proteínas Recombinantes/efectos adversos , Tomografía Computarizada por Rayos X
14.
Blood ; 89(3): 1078-88, 1997 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-9028341

RESUMEN

Hydroxyurea (HU) can increase fetal hemoglobin (HbF) in sickle cell anemia (HbSS). To identify determinants of the HbF response, we studied 150 HU-treated patients grouped by quartiles of change in HbF from baseline to 2 years. Half of the HU-assigned patients had long-term increments in HbF. In the top two quartiles, HbF increased to 18.1% and 8.8%. These patients had the highest baseline neutrophil and reticulocyte counts, and largest treatment-associated decrements in these counts. In the lower two quartiles, 2-year HbF levels (4.2% and 3.9%) and blood counts changed little from baseline. In the highest HbF response quartile, myelosuppression developed in less than 6 months, compliance was best, and final doses of HU were 15 to 22.5 mg/kg. All four quartiles had substantial increases of F cells in the first year. This was maintained for 2 years only in the top three quartiles. Leukocyte and reticulocyte counts decreased initially in all quartiles, but drifted back toward baseline levels in the lowest HbF response quartile. Initial HbF level and phenotype of the F-cell production (FCP) locus were not associated with HbF response, but absence of a Central African Republic (CAR) haplotype was. Bone marrow ability to withstand HU treatment may be important for sustained HbF increases during HU treatment of HbSS.


Asunto(s)
Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/tratamiento farmacológico , Hemoglobina Fetal/efectos de los fármacos , Hidroxiurea/uso terapéutico , Adulto , Recuento de Células Sanguíneas , Método Doble Ciego , Femenino , Estudios de Seguimiento , Globinas/genética , Haplotipos , Humanos , Hidroxiurea/efectos adversos , Masculino , Cooperación del Paciente
15.
Medicine (Baltimore) ; 75(6): 300-26, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8982148

RESUMEN

Painful crises in patients with sickle cell anemia are caused by vaso-occlusion and infarction. Occlusion of blood vessels depends on (at least) their diameter, the deformability of red cells, and the adhesion of blood cells to endothelium. Deoxygenated sickle cells are rigid because they contain linear polymers of hemoglobin S (Hb S); polymerization is highly concentration dependent, and dilution of Hb S by a nonsickling hemoglobin such as fetal hemoglobin (Hb F) would be expected to lead ultimately to a decrease in the frequency of painful crises. It might also be expected to decrease the severity of anemia, although the pathogenesis of anemia in sickle cell anemia (SS disease) is not clearly understood. Reversion to production of fetal rather than adult hemoglobin became practical with the discovery that HU was an orally effective and relatively safe "switching agent." Preliminary dose-ranging studies led to a double-blind randomized controlled clinical trial, the Multicenter Study of Hydroxyurea in Sickle Cell Anemia (MSH), designed to test whether patients treated with HU would have fewer crises than patients treated with placebo. The MSH was not designed to assess the mechanism(s) by which a beneficial effect might be achieved, but it was hoped that observations made during the study might illuminate that question. The 2 MSH treatment groups were similar to each other and were representative of African-American patients with relatively severe disease. The trial was closed earlier than expected, after demonstration that median crisis rate was reduced by almost 50% (2.5 versus 4.5 crises per year) in patients assigned to HU therapy. Hospitalizations, episodes of chest syndrome, and numbers of transfusions were also lower in patients treated with HU. Eight patients died during the trial, and treatment was stopped in 53. There were no instances of alarming toxicity. Patients varied widely in their maximum tolerated doses, but it was not clear that all were taking their prescribed treatments. When crisis frequency was compared with various clinical and laboratory measurements, pretreatment crisis rate and treatment with HU were clearly related to crisis rate during treatment. Pretreatment laboratory measurements were not associated with crisis rates during the study in either treatment group. It was not clear that clinical improvement was associated with an increase in Hb F. Crisis rates of the 2 treatment groups became different within 3 months. Mean corpuscular volumes (MCVs) and the proportion of Hb F containing red cells (F cells) rose, and neutrophil and reticulocyte counts fell, within 7 weeks. When patients were compared on the basis of 2-year crisis rates, those with lower crisis rates had higher F-cell counts and MCVs and lower neutrophil counts. Neutrophil, monocyte, reticulocyte, and platelet counts were directly associated, and F cells and MCV were inversely associated, with crisis rates in 3-month periods. In multivariable analyses, there was strong evidence of independent association of lower neutrophil counts with lower crisis rates. F-cell counts were associated with crisis rate only in the first 3 months of treatment; MCV showed an association over longer periods of time. Overall, the evidence that decreased neutrophil counts played a role in reducing crisis rates was strong. Increased F cells or MCV and evidence of cytoreduction by HU were also associated with decreased crisis rates, but no definitive statement can be made regarding the mechanism of action of HU because the study was not designed to address that question. Future studies should be designed to explore the mechanism of action of HU, to identify the optimal dosage regimen, and to study the effect of HU when combined with other antisickling agents.


Asunto(s)
Anemia de Células Falciformes/tratamiento farmacológico , Antidrepanocíticos/uso terapéutico , Hidroxiurea/uso terapéutico , Adolescente , Adulto , Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/fisiopatología , Antidrepanocíticos/efectos adversos , Recuento de Células Sanguíneas , Método Doble Ciego , Índices de Eritrocitos , Femenino , Hemoglobina Fetal/análisis , Globinas/genética , Humanos , Hidroxiurea/efectos adversos , Masculino , Persona de Mediana Edad
16.
Chest ; 110(5): 1212-9, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8915223

RESUMEN

BACKGROUND: Previous studies suggest that most patients with pulmonary embolism die of their underlying diseases and pulmonary embolism is itself responsible for a minority of deaths. It has not been determined whether pulmonary embolism is associated with increased mortality among patients with different specific diseases. METHODS: We assessed the mortality in 1,487 patients who had lung scans to pursue the diagnosis of pulmonary embolism. An outcome classification committee prospectively reviewed deaths occurring up to 1 year after each patient's entry into the study. RESULTS: Ninety-five (23.8%) patients with pulmonary embolism and 189 (18.9%) without pulmonary embolism died within 1 year of study entry (estimated relative risk, 1.34; 95% confidence interval, 1.01 to 1.79). Mortality according to pulmonary embolism status was different among patients with COPD from mortality among patients who did not have COPD (interaction p = 0.03). Of 45 patients with COPD and pulmonary embolism, 24 (53.3%; 95% confidence interval, 38.8 to 67.9%) died within 1 year. After adjustment for patient characteristics, the estimated risk of dying within 1 year was 1.94 times (95% confidence interval, 1.17 to 3.24) for patients with COPD and pulmonary embolism compared with those without pulmonary embolism, and 1.14 (95% confidence interval, 0.85 to 1.54) for patients without COPD (interaction p = 0.08). CONCLUSIONS: Patients with COPD and pulmonary embolism have an increased 1-year mortality. Further study is needed to clarify the reason(s) for the increase in mortality.


Asunto(s)
Enfermedades Pulmonares Obstructivas/mortalidad , Embolia Pulmonar/mortalidad , Adulto , Causas de Muerte , Comorbilidad , Intervalos de Confianza , Femenino , Estudios de Seguimiento , Humanos , Hipertensión Pulmonar/mortalidad , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo , Tasa de Supervivencia , Estados Unidos/epidemiología
17.
Control Clin Trials ; 16(6): 432-46, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8925656

RESUMEN

The Multicenter Study of Hydroxyurea in Sickle Cell Anemia is a randomized double-blind placebo-controlled trial to test whether hydroxyurea can reduce the rate of painful crises in adult patients who have at least three painful crises per year. The sample size of 299 patients yields at least 90% power to detect a 50% or greater reduction in crisis rate. Dosage starts at 15 mg/kg/day and is titrated to the patient's maximum tolerated dose up to 35 mg/kg/day. Placebo dosage is titrated in similar fashion to maintain blinding. Attempts are made to ascertain medical contacts for at least 2 years after study entry. The Core Laboratory, Treatment Distribution Center, and Data Coordinating Center collaborate to provide standardized monitoring for toxicity and dose adjustments. The Core Laboratory also reduces the possibility of inadvertent unmasking of treatment assignment during review of hematologic data in clinical centers. An independent Crisis Review Committee classifies clinical events to assure that outcome evaluations are standardized and unbiased by knowledge of treatment assignments. The Data and Safety Monitoring Board assures scientific integrity of the study, as well as the safety and ethical treatment of study patients. We expect the study to determine whether or not treatment with hydroxyurea can offer significant clinical benefit to patients with the most common hereditary disorder among African-Americans in the United States.


Asunto(s)
Anemia de Células Falciformes/tratamiento farmacológico , Antidrepanocíticos/uso terapéutico , Hidroxiurea/uso terapéutico , Proyectos de Investigación , Adulto , Anemia de Células Falciformes/sangre , Método Doble Ciego , Femenino , Hemoglobina Fetal/genética , Hemoglobina Fetal/metabolismo , Humanos , Masculino , Selección de Paciente , Placebos , Calidad de Vida , Tamaño de la Muestra
18.
J Am Coll Cardiol ; 26(1): 73-9, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7797778

RESUMEN

OBJECTIVES: This study sought to determine the prognostic value of rest and exercise left ventricular ejection fraction in patients receiving thrombolytic therapy as part of the Thrombolysis in Myocardial Infarction (TIMI) trial. BACKGROUND: In the prethrombolytic era, ejection fraction at rest as well as during exercise was an important prognostic index in patients recovering from acute myocardial infarction. The prognostic value of these measurements in the thrombolytic era is not clear. METHODS: As part of the TIMI II protocol, we obtained radionuclide left ventricular ejection fraction at rest and during symptom-limited submaximal supine exercise. Measurements were related to 1-year all-cause as well as cardiac mortality. In addition, the relation between ejection fraction obtained at rest and 1-year cardiac mortality in this study was compared with the relation established previously in the prethrombolytic era by the Multicenter Postinfarction Research Group. RESULTS: A distinct relation was noted between left ventricular ejection fraction at rest and all-cause mortality. The highest mortality rate (9.9%) was noted in patients with an ejection fraction < 30%. Those not undergoing a study had a 1-year mortality rate of 6.2%. Peak exercise ejection fraction provided prognostic information similar to that of rest ejection fraction. Likewise, change in ejection fraction from rest to exercise did not appreciably improve prognostic impact. CONCLUSIONS: Rest left ventricular ejection fraction is an important prognostic index in patients receiving thrombolytic therapy. Peak exercise ejection fraction and the change in ejection fraction from rest to exercise do not provide appreciable prognostic data beyond those obtained at rest. Patients unable to exercise or those not having a rest study have a poor prognosis. When compared with the Multicenter Postinfarction Research Group data, there was strong evidence of a difference in survival in the two studies. At any level of ejection fraction, mortality was lower in TIMI II patients than in patients in the prethrombolytic era.


Asunto(s)
Infarto del Miocardio/mortalidad , Volumen Sistólico , Terapia Trombolítica , Anciano , Ejercicio Físico/fisiología , Corazón/diagnóstico por imagen , Humanos , Persona de Mediana Edad , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/fisiopatología , Pronóstico , Cintigrafía , Análisis de Supervivencia
19.
N Engl J Med ; 332(20): 1317-22, 1995 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-7715639

RESUMEN

BACKGROUND: In a previous open-label study of hydroxyurea therapy, the synthesis of fetal hemoglobin increased in most patients with sickle cell anemia, with only mild myelotoxicity. By inhibiting sickling, increased levels of fetal hemoglobin might decrease the frequency of painful crises. METHODS: In a double-blind, randomized clinical trial, we tested the efficacy of hydroxyurea in reducing the frequency of painful crises in adults with a history of three or more such crises per year. The trial was stopped after a mean follow-up of 21 months. RESULTS: Among 148 men and 151 women studied at 21 clinics, the 152 patients assigned to hydroxyurea treatment had lower annual rates of crises than the 147 patients given placebo (median, 2.5 vs. 4.5 crises per year, P < 0.001). The median times to the first crisis (3.0 vs. 1.5 months, P = 0.01) and the second crisis (8.8 vs. 4.6 months, P < 0.001) were longer with hydroxyurea treatment. Fewer patients assigned to hydroxyurea had chest syndrome (25 vs. 51, P < 0.001), and fewer underwent transfusions (48 vs. 73, P = 0.001). At the end of the study, the doses of hydroxyurea ranged from 0 to 35 mg per kilogram of body weight per day. Treatment with hydroxyurea did not cause any important adverse effects. CONCLUSIONS: Hydroxyurea therapy can ameliorate the clinical course of sickle cell anemia in some adults with three or more painful crises per year. Maximal tolerated doses of hydroxyurea may not be necessary to achieve a therapeutic effect. The beneficial effects of hydroxyurea do not become manifest for several months, and its use must be carefully monitored. The long-term safety of hydroxyurea in patients with sickle cell anemia is uncertain.


Asunto(s)
Anemia de Células Falciformes/tratamiento farmacológico , Hidroxiurea/uso terapéutico , Dolor/prevención & control , Adulto , Anemia de Células Falciformes/fisiopatología , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Masculino
20.
Neurology ; 45(4): 649-58, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7723950

RESUMEN

Parenchymatous intracerebral hemorrhage (ICH) is a serious, infrequent complication of thrombolytic therapy for acute myocardial infarction. We studied the clinical and radiologic features, manner of presentation, associated factors, and temporal course in 23 patients with ICH associated with 150 mg or 100 mg recombinant tissue-type plasminogen activator (rt-PA) and heparin therapy for acute myocardial infarction in the Thrombolysis in Myocardial Infarction (TIMI) II Pilot and Randomized Clinical Trial. In TIMI II, 13 of the 23 ICH patients developed or maintained systolic blood pressure > or = 160 mm Hg or diastolic blood pressure > or = 90 mm Hg during the rt-PA infusion and before the onset of neurologic symptoms. Six patients (26%) had life-threatening ventricular arrhythmias, five before onset of neurologic symptoms. A decreased level of consciousness was the earliest neurologic abnormality in 15 (65%) and the most common initial physical finding (in 19, or 82%). Onset was usually gradual (70%), but time to maximal deficit was frequently (61%) within 6 hours of onset. The locations of the primary ICH sites were lobar in 16 (70%), thalamic in four (17%), and brainstem-cerebellum in three (13%), but the putamen was never the primary site. Multiple lobar hemorrhages occurred in six cases (26%). The timing and size of ICH was similar among patients treated with 150 mg rt-PA and 100 mg rt-PA. Brain CT demonstrated an arteriovenous malformation in one case. Four patients had hypofibrinogenemia, which was profound in three patients. Pathologic findings were available for five patients. Of these, three patients had cerebral amyloid angiopathy, and one had hemorrhagic transformation of an ischemic cerebral infarction found at autopsy. We conclude that ICH following rt-PA and heparin therapy for acute myocardial infarction presents as a distinctive clinical syndrome. Intracerebral bleeding after combined thrombolytic and antithrombotic therapy may be associated with cerebral amyloid angiopathy and other vascular lesions. Acute or persistent hypertension before or during rt-PA infusion, life-threatening ventricular arrhythmias, and hypofibrinogenemia, either alone or in combination, may play roles in some cases. Care should be exercised when considering thrombolytic therapy for patients with risk factors for ICH.


Asunto(s)
Hemorragia Cerebral/inducido químicamente , Heparina/efectos adversos , Infarto del Miocardio/tratamiento farmacológico , Terapia Trombolítica/efectos adversos , Activador de Tejido Plasminógeno/efectos adversos , Adulto , Anciano , Hemorragia Cerebral/patología , Hemorragia Cerebral/fisiopatología , Femenino , Heparina/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Factores de Riesgo , Activador de Tejido Plasminógeno/uso terapéutico
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