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BACKGROUND: Wearable devices are increasingly used in research and clinical care though the relevance of their data in the context of validated outcomes remains unknown. OBJECTIVES: The purpose of this study was to characterize the relationship between smartwatch activity and patient-centered outcomes in patients with heart failure. METHODS: CHIEF-HF (Canagliflozin: Impact on Health Status, Quality of Life and Functional Status in Heart Failure) was a randomized-controlled clinical trial that enrolled participants with heart failure and a compatible smartphone. Participants were provided a Fitbit Versa 2 and completed serial Kansas City Cardiomyopathy Questionnaires (KCCQs) through a smartphone application. We evaluated the relationship between daily step count and floors climbed and KCCQ total symptom (TS) and physical limitation (PL) scores at baseline and their respective changes between 2 and 12 weeks using linear regression models, with restricted cubic splines for nonlinear associations. RESULTS: In total, 425 patients were included: 44.5% women, 40.9% with reduced ejection fraction. Baseline daily step count increased across categories of KCCQ-TS scores (2,437.6 ± 1,419.5 steps/d for scores 0 to 24 vs 4,870.9 ± 3,171.3 steps/d for scores 75 to 100; P < 0.001) with similar results for KCCQ-PL scores. This relationship remained significant for KCCQ-TS and KCCQ-PL scores after multivariable adjustment. Importantly, changes in daily step count were significantly associated with nonlinear changes in KCCQ-TS (P = 0.004) and KCCQ-PL (P = 0.003) scores. Floors climbed was associated with baseline KCCQ scores alone. CONCLUSIONS: Daily step count was nonlinearly associated with health status at baseline and over time in patients with heart failure. These results may inform interpretation of wearable device data in clinical and research contexts. (A Study on Impact of Canagliflozin on Health Status, Quality of Life, and Functional Status in Heart Failure [CHIEF-HF]; NCT04252287).
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Insuficiencia Cardíaca , Dispositivos Electrónicos Vestibles , Humanos , Femenino , Masculino , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/diagnóstico , Calidad de Vida , Canagliflozina , Estado de Salud , Medición de Resultados Informados por el Paciente , Volumen SistólicoRESUMEN
BACKGROUND: There has been growing Interest in patient-centered clinical trials using mobile technologies to reduce the need for in-person visits. The CHIEF-HF (Canagliflozin Impact on Health Status, Quality of Life and Functional Status in Heart Failure) trial was designed as a double-blind, randomized, fully decentralized clinical trial (DCT) that identified, consented, treated, and followed participants without any in-person visits. Patient-reported questionnaires were the primary outcome, which were collected by a mobile application. To inform future DCTs, we sought to describe the strategies used in successful trial recruitment. METHODS: This article describes the operational structure and novel strategies employed in a completely DCT by summarizing the recruitment, enrollment, engagement, retention, and follow-up processes used in the execution of the trial at 18 centers. RESULTS: A total of 18 sites contacted 130,832 potential participants, of which 2572 (2.0%) opened a hyperlink to the study website, completed a brief survey, and agreed to be contacted for potential inclusion. Of these, 1333 were eligible, and 658 consented; there were 182 screen failures, due primarily to baseline Kansas City Cardiomyopathy Questionnaire scores' not meeting inclusion criteria, resulting in 476 participants' being enrolled (18.5%). There was significant site-level variation in the number of patients invited (medianâ¯=â¯2976; range 73-46,920) and in those agreeing to be contacted (medianâ¯=â¯2.4%; range 0.05%-16.4%). At the site with the highest enrollment, patients contacted by electronic medical record portal messaging were more likely to opt into the study successfully than those contacted by e-mail alone (7.8% vs 4.4%). CONCLUSIONS: CHIEF-HF used a novel design and operational structure to test the efficacy of a therapeutic treatment, but marked variability across sites and strategies for recruiting participants was observed. This approach may be advantageous for clinical research across a broader range of therapeutic areas, but further optimization of recruitment efforts is warranted. REGISTRATION: NCT04252287 https://clinicaltrials.gov/ct2/show/NCT04252287.
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Insuficiencia Cardíaca , Calidad de Vida , Humanos , Canagliflozina , Estado Funcional , Insuficiencia Cardíaca/tratamiento farmacológico , Estado de SaludRESUMEN
Large traditional clinical trials suggest that sodium-glucose co-transporter 2 inhibitors improve symptoms in patients with heart failure and reduced ejection fraction (HFrEF) and in patients with heart failure and preserved ejection fraction (HFpEF). In the midst of the Coronavirus Disease 2019 pandemic, we sought to confirm these benefits in a new type of trial that was patient centered and conducted in a completely remote fashion. In the CHIEF-HF trial ( NCT04252287 ), 476 participants with HF, regardless of EF or diabetes status, were randomized to 100 mg of canagliflozin or placebo. Enrollment was stopped early due to shifting sponsor priorities, without unblinding. The primary outcome was change in the Kansas City Cardiomyopathy Questionnaire Total Symptom Score (KCCQ TSS) at 12 weeks. The 12-week change in KCCQ TSS was 4.3 points (95% confidence interval, 0.8-7.8; P = 0.016) higher with canagliflozin than with placebo, meeting the primary endpoint. Similar effects were observed in participants with HFpEF and in those with HFrEF and in participants with and without diabetes, demonstrating that canagliflozin significantly improves symptom burden in HF, regardless of EF or diabetes status. This randomized, double-blind trial, conducted without in-person interactions between doctor and patient, can serve as a model for future all-virtual clinical trials.
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COVID-19 , Insuficiencia Cardíaca , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Disfunción Ventricular Izquierda , Canagliflozina/farmacología , Canagliflozina/uso terapéutico , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Atención Dirigida al Paciente , Calidad de Vida , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Volumen SistólicoRESUMEN
Importance: Current guidelines recommend against use of intravenous alteplase in patients with acute ischemic stroke who are taking non-vitamin K antagonist oral anticoagulants (NOACs). Objective: To evaluate the safety and functional outcomes of intravenous alteplase among patients who were taking NOACs prior to stroke and compare outcomes with patients who were not taking long-term anticoagulants. Design, Setting, and Participants: A retrospective cohort study of 163â¯038 patients with acute ischemic stroke either taking NOACs or not taking anticoagulants prior to stroke and treated with intravenous alteplase within 4.5 hours of symptom onset at 1752 US hospitals participating in the Get With The Guidelines-Stroke program between April 2015 and March 2020, with complementary data from the Addressing Real-world Anticoagulant Management Issues in Stroke registry. Exposures: Prestroke treatment with NOACs within 7 days prior to alteplase treatment. Main Outcomes and Measures: The primary outcome was symptomatic intracranial hemorrhage occurring within 36 hours after intravenous alteplase administration. There were 4 secondary safety outcomes, including inpatient mortality, and 7 secondary functional outcomes assessed at hospital discharge, including the proportion of patients discharged home. Results: Of 163â¯038 patients treated with intravenous alteplase (median age, 70 [IQR, 59 to 81] years; 49.1% women), 2207 (1.4%) were taking NOACs and 160â¯831 (98.6%) were not taking anticoagulants prior to their stroke. Patients taking NOACs were older (median age, 75 [IQR, 64 to 82] years vs 70 [IQR, 58 to 81] years for those not taking anticoagulants), had a higher prevalence of cardiovascular comorbidities, and experienced more severe strokes (median National Institutes of Health Stroke Scale score, 10 [IQR, 5 to 17] vs 7 [IQR, 4 to 14]) (all standardized differences >10). The unadjusted rate of symptomatic intracranial hemorrhage was 3.7% (95% CI, 2.9% to 4.5%) for patients taking NOACs vs 3.2% (95% CI, 3.1% to 3.3%) for patients not taking anticoagulants. After adjusting for baseline clinical factors, the risk of symptomatic intracranial hemorrhage was not significantly different between groups (adjusted odds ratio [OR], 0.88 [95% CI, 0.70 to 1.10]; adjusted risk difference [RD], -0.51% [95% CI, -1.36% to 0.34%]). There were no significant differences in the secondary safety outcomes, including inpatient mortality (6.3% for patients taking NOACs vs 4.9% for patients not taking anticoagulants; adjusted OR, 0.84 [95% CI, 0.69 to 1.01]; adjusted RD, -1.20% [95% CI, -2.39% to -0%]). Of the secondary functional outcomes, 4 of 7 showed significant differences in favor of the NOAC group after adjustment, including the proportion of patients discharged home (45.9% vs 53.6% for patients not taking anticoagulants; adjusted OR, 1.17 [95% CI, 1.06 to 1.29]; adjusted RD, 3.84% [95% CI, 1.46% to 6.22%]). Conclusions and Relevance: Among patients with acute ischemic stroke treated with intravenous alteplase, use of NOACs within the preceding 7 days, compared with no use of anticoagulants, was not associated with a significantly increased risk of intracranial hemorrhage.
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Anticoagulantes/uso terapéutico , Fibrinolíticos/uso terapéutico , Hemorragias Intracraneales/etiología , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Activador de Tejido Plasminógeno/uso terapéutico , Administración Intravenosa , Administración Oral , Anciano , Anciano de 80 o más Años , Anticoagulantes/efectos adversos , Femenino , Humanos , Accidente Cerebrovascular Isquémico/complicaciones , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de RiesgoRESUMEN
BACKGROUND: The expense of clinical trials mandates new strategies to efficiently generate evidence and test novel therapies. In this context, we designed a decentralized, patient-centered randomized clinical trial leveraging mobile technologies, rather than in-person site visits, to test the efficacy of 12 weeks of canagliflozin for the treatment of heart failure, regardless of ejection fraction or diabetes status, on the reduction of heart failure symptoms. METHODS: One thousand nine hundred patients will be enrolled with a medical record-confirmed diagnosis of heart failure, stratified by reduced (≤40%) or preserved (>40%) ejection fraction and randomized 1:1 to 100 mg daily of canagliflozin or matching placebo. The primary outcome will be the 12-week change in the total symptom score of the Kansas City Cardiomyopathy Questionnaire. Secondary outcomes will be daily step count and other scales of the Kansas City Cardiomyopathy Questionnaire. RESULTS: The trial is currently enrolling, even in the era of the coronavirus disease 2019 (COVID-19) pandemic. CONCLUSIONS: CHIEF-HF (Canagliflozin: Impact on Health Status, Quality of Life and Functional Status in Heart Failure) is deploying a novel model of conducting a decentralized, patient-centered, randomized clinical trial for a new indication for canagliflozin to improve the symptoms of patients with heart failure. It can model a new method for more cost-effectively testing the efficacy of treatments using mobile technologies with patient-reported outcomes as the primary clinical end point of the trial. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04252287.
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Canagliflozina/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Telemedicina , Actigrafía/instrumentación , Canagliflozina/efectos adversos , Método Doble Ciego , Tolerancia al Ejercicio/efectos de los fármacos , Monitores de Ejercicio , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Humanos , Aplicaciones Móviles , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Recuperación de la Función , Inhibidores del Cotransportador de Sodio-Glucosa 2/efectos adversos , Volumen Sistólico/efectos de los fármacos , Telemedicina/instrumentación , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos , Función Ventricular Izquierda/efectos de los fármacosRESUMEN
BACKGROUND: Improving adherence to direct oral anticoagulants (DOAC) is challenging, and simple text messaging reminders have not been effective. METHODS: SmartADHERE was a randomized trial that tested a personalized digital and human direct oral anticoagulant adherence intervention compared to usual care. Eligibility required age ≥ 18, newly-prescribed (≤90 days) rivaroxaban for atrial fibrillation (AF), 1 of 4 at-risk criteria for nonadherence, and a smartphone. The intervention consisted of combination of a medication management smartphone app, daily app-based reminders, adaptive text messaging, and phone-based counseling for severe nonadherence. The primary outcome was the proportion of days covered by rivaroxaban (PDC) at 6 months. There were 25 U.S. sites, all cardiology and electrophysiology outpatient practices, activated for a target sample size of 378, but the study was terminated by the sponsor prior to reaching target enrollment. RESULTS: There were 139 participants (age 65±9.6 years, 30% female, median CHA2DS2-VASc score 3 with IQR 2 to 4, mean total medication burden 7.7±4.4). DOAC adherence was high in both arms with no difference in the primary outcome (PDC 0.86±0.25 intervention vs 0.88±0.25 control, p=0.62) or in secondary outcomes including PDC ≥ 0.80 and medication persistence. Per protocol analyses had similar results. Because of the high overall PDC, the likelihood to answer the primary hypothesis was only 51% even if target enrollment were achieved. There were no study-related adverse events. CONCLUSIONS: The use of a centralized digital and human adherence intervention was feasible across multiple sites. Overall adherence was much higher than expected despite prescreening for at-risk individuals. SmartADHERE illustrates the challenges of trials of behavioral and technology interventions, where enrollment itself may lead to selection bias or treatment effects. Pragmatic study designs, such as cluster randomization or stepped-wedge implementation, should be considered to improve enrollment and generalizability.
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Fibrilación Atrial/tratamiento farmacológico , Electrónica , Rivaroxabán/administración & dosificación , Teléfono Inteligente , Accidente Cerebrovascular/prevención & control , Administración Oral , Anciano , Fibrilación Atrial/complicaciones , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Inhibidores del Factor Xa/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Estudios Retrospectivos , Accidente Cerebrovascular/etiologíaRESUMEN
OBJECTIVE: The objective was to determine whether a 3-question version of the Edinburgh Postpartum Depression Scale (EPDS) performs as well as the full EPDS in screening for postpartum depression in a pediatric emergency department (PED). METHODS: Mothers of infants younger than 6 months presenting to an urban PED were enrolled. After the PED encounter, mothers were asked about demographics, health problems, insurance status, social support, food and housing security, and 3 questions from the EPDS. Mothers then completed the full EPDS. The primary outcome was the score on the full EPDS. Agreement between the 3 questions and the full EPDS for screening positive was measured. Test performance characteristics for screening positive with the 3 questions were calculated. Logistic regression determined the association between sociodemographic characteristics and screening positive. Provider impression of maternal depressive symptoms was recorded. RESULTS: Of 195 mothers enrolled, 23% screened positive using the EPDS; 34% screened positive using the 3 questions (κ = 0.74). Compared with the EPDS, sensitivity of the 3 questions was 100%. Number of children younger than 5 years at home and having food and housing concerns were associated with screening positive. Of 44 mothers who screened positive on the full EPDS, providers identified 14 (32%) as having depressive symptoms or possibly being depressed. CONCLUSIONS: Three questions from the EPDS performed similarly to the full EPDS in screening for postpartum depressive symptoms in a PED. Future studies are needed to confirm these findings and examine whether screening improves maternal and child health outcomes and quality-of-life concerns.
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Depresión Posparto/diagnóstico , Servicio de Urgencia en Hospital/organización & administración , Tamizaje Masivo/organización & administración , Índice de Severidad de la Enfermedad , Adulto , Estudios Transversales , Depresión Posparto/epidemiología , Femenino , Humanos , Lactante , Recién Nacido , Ciudad de Nueva York/epidemiología , Paridad , Pediatría/organización & administración , Pobreza , Embarazo , Prevalencia , Factores de Riesgo , Sensibilidad y Especificidad , Método Simple Ciego , Factores Socioeconómicos , Ideación Suicida , Encuestas y Cuestionarios , Adulto JovenRESUMEN
BACKGROUND: Vancomycin is commonly used to treat staphylococcal infections, but there has not been a definitive analysis of the pharmacokinetics of this antibacterial in relation to minimum inhibitory concentration (MIC) that could be used to determine a target pharmacodynamic index for treatment optimisation. OBJECTIVE: To clarify relationships between vancomycin dosage, serum concentration, MIC and antimicrobial activity by using data gathered from a therapeutic monitoring environment that observes failures in some cases. METHODS: We investigated all patients with a Staphylococcus aureus lower respiratory tract infection at a 300-bed teaching hospital in the US during a 1-year period. Clinical and pharmacokinetic information was used to determine the following: (i) whether steady-state 24-hour area under the concentration-time curve (AUC24) divided by the MIC (AUC24/MIC) values for vancomycin could be precisely calculated with a software program; (ii) whether the percentage of time vancomycin serum concentrations were above the MIC (%Time>MIC) was an important determinant of vancomycin response; (iii) whether the time to bacterial eradication differed as the AUC24/MIC value increased; (iv) whether the time to bacterial eradication for vancomycin differed compared with other antibacterials at the same AUC24/MIC value; and (v) whether a relationship existed between time to bacterial eradication and time to significant clinical improvement of pneumonia symptoms. RESULTS: The median age of the 108 patients studied was 74 (range 32-93) years. Measured vancomycin AUC24/MIC values were precisely predicted with the A.U.I.C. calculator in a subset of our patients (r2 = 0.935). Clinical and bacteriological response to vancomycin therapy was superior in patients with higher (> or = 400) AUC24/MIC values (p = 0.0046), but no relationship was identified between vancomycin %Time>MIC and infection response. Bacterial eradication of S. aureus (both methicillin-susceptible and methicillin-resistant) occurred more rapidly (p = 0.0402) with vancomycin when a threshold AUC24/MIC value was reached. S. aureus killing rates were slower with vancomycin than with other antistaphylococcal antibacterials (p = 0.002). There was a significant relationship (p < 0.0001) between time to bacterial eradication and the time to substantial improvement in pneumonia score. CONCLUSIONS: Vancomycin AUC24/MIC values predict time-related clinical and bacteriological outcomes for patients with lower respiratory tract infections caused by methicillin-resistant S. aureus.
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Antibacterianos/farmacología , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Infecciones Estafilocócicas/tratamiento farmacológico , Vancomicina/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Área Bajo la Curva , Femenino , Hospitales de Enseñanza , Humanos , Masculino , Resistencia a la Meticilina , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Staphylococcus aureus/efectos de los fármacos , Factores de Tiempo , Resultado del Tratamiento , Vancomicina/uso terapéuticoRESUMEN
OBJECTIVE: To characterise the pharmacokinetic-pharmacodynamic relationships for linezolid efficacy. DESIGN AND STUDY POPULATION: Retrospective nonblinded analysis of severely debilitated adult patients with numerous comorbid conditions and complicated infections enrolled under the manufacturer's compassionate use programme. METHODS: Patients received intravenous or oral linezolid 600 mg every 12 hours. Plasma concentrations were obtained and a multicompartmental pharmacokinetic model was fitted. Numerical integration of the fitted functions provided the area under the concentration-time curve over 24 hours (AUC), the ratio of AUC to minimum inhibitory concentration (AUC/MIC) and the percentage of time that plasma concentrations exceeded the MIC (%T>MIC). MAIN OUTCOME MEASURES: Modelled pharmacodynamic outcomes of efficacy included probabilities of eradication and clinical cure (multifactorial logistic regression, nonparametric tree-based modelling, nonlinear regression) and time to bacterial eradication (Kaplan-Meier and Cox proportional hazards regression). Factors considered included AUC/MIC, %T>MIC, site of infection, bacterial species and MIC, and other medical conditions. RESULTS: There were 288 cases evaluable by at least one of the efficacy outcomes. Both %T>MIC and AUC/MIC were highly correlated (Spearman r2 = 0.868). In our analyses, within specific infection sites, the probability of eradication and clinical cure appeared to be related to AUC/MIC (eradication: bacteraemia, skin and skin structure infection [SSSI], lower respiratory tract infection [LRTI], bone infection; clinical cure: bacteraemia, LRTI) and %T>MIC (eradication: bacteraemia, SSSI, LRTI; clinical cure: bacteraemia, LRTI). Time to bacterial eradication for bacteraemias appeared to be related to the AUC, %T>MIC and AUC/MIC. For most sites, AUC/MIC and %T>MIC models performed similarly. CONCLUSIONS: Higher success rates for linezolid may occur at AUC/MIC values of 80-120 for bacteraemia, LRTI and SSSI. Chance of success in bacteraemia, LRTI and SSSI also appear to be higher when concentrations remain above the MIC for the entire dosing interval.
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Acetamidas/uso terapéutico , Antiinfecciosos/uso terapéutico , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Hígado/efectos de los fármacos , Oxazolidinonas/uso terapéutico , Acetamidas/farmacocinética , Acetamidas/farmacología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antiinfecciosos/farmacocinética , Antiinfecciosos/farmacología , Área Bajo la Curva , Comorbilidad , Femenino , Infecciones por Bacterias Grampositivas/metabolismo , Humanos , Linezolid , Hígado/metabolismo , Modelos Logísticos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Oxazolidinonas/farmacocinética , Oxazolidinonas/farmacología , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del TratamientoRESUMEN
Linezolid was provided for treatment of multidrug-resistant, gram-positive infections through a compassionate-use program. Patients (n=796) received 600 mg of linezolid intravenously or orally every 12 h (828 treatment courses). Bacteremia was present in 46% of infections, endocarditis was present in 10.6%, and line-related infections were present in 31.1%. Other infections included intraabdominal infections (15.1%), complicated skin and skin-structure infections (13.3%), and osteomyelitis (10.7%). Causative pathogens included vancomycin-resistant enterococci (66.3%) and methicillin-resistant staphylococci (22.1%). Clinical intent-to-treat (ITT) outcomes in the evaluable population were as follows: cure, 73.3%; failure, 6.8%; and indeterminate, 19.9%. Microbiological ITT outcomes in evaluable patients were as follows: cure, 82.4%; failure, 14.1%; and indeterminate, 3.5%. At the test of cure assessment, the clinical cure and microbiological success rates were 91.5% and 85.8%, respectively. The most common adverse events possibly related to linezolid use were gastrointestinal disturbances (9.8% of cases), thrombocytopenia (7.4% of cases), decreased hemoglobin/hematocrit levels (4.1% of cases), and cutaneous reactions (4.0% of cases). Linezolid provided high rates of clinical cure and microbiological success in this complicated patient population, with very good overall tolerance.
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Acetamidas/uso terapéutico , Antiinfecciosos/uso terapéutico , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Oxazolidinonas/uso terapéutico , Acetamidas/efectos adversos , Adolescente , Adulto , Anciano , Antiinfecciosos/efectos adversos , Interacciones Farmacológicas , Farmacorresistencia Bacteriana , Resistencia a Múltiples Medicamentos , Femenino , Humanos , Linezolid , Masculino , Persona de Mediana Edad , Oxazolidinonas/efectos adversos , Resultado del TratamientoRESUMEN
Linezolid is an oxazolidinone that has activity against most gram-positive bacteria, including in vitro activity against all Nocardia species and strains. We describe 6 clinical cases of nocardiosis that were successfully treated with linezolid. Two patients had underlying X-linked chronic granulomatous disease, and 2 patients were receiving chronic corticosteroid therapy. Four of 6 patients had disseminated disease, and 2 of these 4 patients had multiple brain abscesses. Four patients primarily received monotherapy; for the fifth patient, linezolid was added to a failing multiple-drug regimen, and, for the sixth patient, it was used as part of combination therapy. All 6 patients were successfully treated, although 1 patient had a presumed relapse of central nervous system infection after premature discontinuation of the drug. Linezolid appears to be an effective alternative for the treatment of nocardiosis.
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Acetamidas/uso terapéutico , Antibacterianos/uso terapéutico , Nocardiosis/tratamiento farmacológico , Nocardia , Oxazolidinonas/uso terapéutico , Niño , Femenino , Humanos , Linezolid , Masculino , Persona de Mediana Edad , Nocardia/efectos de los fármacos , Resultado del TratamientoRESUMEN
Data obtained from 318 adult patients treated under the linezolid compassionate-use protocol were used to develop a population model of the pharmacokinetics of intravenous and oral linezolid. All of the patients received 600 mg of linezolid every 12 h, intravenously and/or orally. Blood samples (2 to 10 per patient; median, 4) were obtained and assayed for linezolid by high-performance liquid chromatography. These data and patient covariates were modeled by iterative two-stage analysis, and model discrimination was done by Akaike's information criterion. Of the patient covariates considered (age, sex, ideal body weight, baseline serum albumin, hepatic or renal dysfunction, underlying malignancy, organ transplantation, surgical status, global severity of illness, site of infection, route of administration, and location of care [intensive-care unit, general floor, or outpatient]), only normalized creatinine clearance (CL(CR)) and body weight explained significant portions of the variance and were incorporated into the pharmacokinetic model. The final model included central and peripheral compartments with parallel capacity-limited (nonrenal) and first-order (renal [CL(R)]) clearances. Volumes and clearances were normalized to the ideal body weight, and CL(R) was modeled as proportional to CL(CR). Compared to previously studied adult volunteers, intrinsic clearance was approximately 60% higher and the maximum rate of metabolism was twice as high in these debilitated patients, resulting in lower area under the time-concentration curve (AUC) values (P < 0.001). The derived 24-h AUC, averaged over the first 7 days of treatment, ranged between 57 and 871 (median, 191) micro g/ml. 24 h. Despite these variations, linezolid provided high rates of clinical cure, as well as microbiological success, in the patients treated in the compassionate-use program. The mechanism(s) of these pharmacokinetic differences is unknown and requires further mechanistic study.
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Acetamidas/farmacocinética , Antiinfecciosos/farmacocinética , Infecciones Bacterianas/metabolismo , Oxazolidinonas/farmacocinética , Acetamidas/administración & dosificación , Acetamidas/uso terapéutico , Administración Oral , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antiinfecciosos/administración & dosificación , Antiinfecciosos/uso terapéutico , Área Bajo la Curva , Infecciones Bacterianas/tratamiento farmacológico , Disponibilidad Biológica , Femenino , Semivida , Humanos , Inyecciones Intravenosas , Linezolid , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Oxazolidinonas/administración & dosificación , Oxazolidinonas/uso terapéuticoRESUMEN
OBJECTIVE: The incidence of infections caused by methicillin-resistant Staphylococcus aureus continues to increase annually. Unfortunately, only a few therapeutic agents are available for the treatment of patients with such infections and all of the existing drugs have limitations. A pressing need exists, therefore, to identify new antibiotics for use in this clinical setting. The efficacy and safety of linezolid were studied in a compassionate use treatment programme and the results of treating a subset of patients with S. aureus infections are presented here. METHODS: Patients received linezolid in a dosage of 600 mg intravenously (iv) and/or orally twice daily. Clinical and bacteriological responses were assessed after a minimum of 7 days and following completion of therapy. RESULTS: Seven hundred and ninety-six patients who suffered 828 episodes of infection were enrolled in the linezolid compassionate use protocol. Of these, 183 patients received linezolid for 191 infections caused by S. aureus; in 151 cases, patients were intolerant of vancomycin, had a mixed S. aureus/vancomycin-resistant enterococcal infection or had no iv access, and, in 40 cases, patients had failed to respond to treatment with vancomycin. The median age of the patients was 57 years (range 14-93 years) and 53.9% were female. The predominant sites of infection were as follows: bone or joint (27.2%); skin and skin structure (25.1%); bloodstream (20.9%); and lower respiratory tract (12.6%). The clinical success rates in the clinically evaluable and all-treated populations were 83.9% and 62.3%, respectively, whereas the bacteriological eradication rates were 76.9% and 70.2% in the bacteriologically evaluable and all-treated populations, respectively. Linezolid was well tolerated. In 76 (39.8%) of the 191 episodes of infection, patients experienced one or more adverse events or exhibited one or more abnormal laboratory results; in 35 (18.3%) of the 191 cases it was necessary to discontinue treatment. Gastrointestinal tract-related symptoms (nausea, vomiting and diarrhoea) were the most common possibly or probably related adverse events and the most common reasons for drug discontinuation. CONCLUSIONS: Linezolid was effective and well tolerated in patients with S. aureus infections who were enrolled in this compassionate use protocol.