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1.
Liver Int ; 43(8): 1663-1676, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37183524

RESUMEN

BACKGROUND & AIMS: Infection with the hepatitis D virus (HDV) causes the most severe form of viral hepatitis with a high risk to develop clinical complications of liver disease. In addition, hepatitis delta has been shown to be associated with worse patient-reported outcomes. Until recently, only pegylated interferon alfa could be used to treat hepatitis delta. METHODS: Here, we investigated quality of life (QOL) as assessed by the Short Form 36 Health Survey (SF-36) in patients undergoing antiviral therapy with pegylated interferon alfa (PEG-IFNa-2a)-based treatment in the HIDIT-II trial. HIDIT-II was a randomized prospective trial exploring PEG-IFNa-2a with tenofovir disoproxil (TDF) or placebo for 96 weeks in patients with compensated hepatitis delta. Surveys completed by 83 study participants before, during, and after treatments were available. RESULTS: Overall, we observed a reduced QOL of HDV patients compared with a reference population, both in physical as well as mental scores. Interestingly, PEG-IFNa-2a treatment showed only minor impairment of the QOL during therapy. Moreover, HDV-RNA clearance was not associated with relevant changes in physical or social SF-36 scores, whereas an improvement of fibrosis during treatment was associated with increased QOL. Overall, slight improvements of the QOL scores were observed 24 weeks after the end of treatment as compared with baseline. TDF co-treatment had no influence on QOL. CONCLUSIONS: Overall, our findings suggest that PEG-IFNa-2a was reasonably tolerated even over a period of 96 weeks by hepatitis D patients reporting SF-36 questionnaires. Of note, several patients may benefit from PEG-IFNa-2a-based therapies with off-treatment improvements in quality of life.


Asunto(s)
Antivirales , Hepatitis D , Humanos , Antivirales/efectos adversos , Calidad de Vida , Estudios Prospectivos , Resultado del Tratamiento , Polietilenglicoles/uso terapéutico , Quimioterapia Combinada , Interferón-alfa/uso terapéutico , Interferón-alfa/efectos adversos , Hepatitis D/tratamiento farmacológico , Virus de la Hepatitis Delta/genética , ARN Viral , Proteínas Recombinantes/efectos adversos
2.
Pharm Stat ; 22(6): 1046-1061, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37519010

RESUMEN

Pre-specification of the primary analysis model is a pre-requisite to control the family-wise type-I-error rate (T1E) at the intended level in confirmatory clinical trials. However, mixed models for repeated measures (MMRM) have been shown to be poorly specified in study protocols. The magnitude of a resulting T1E rate inflation is still unknown. This investigation aims to quantify the magnitude of the T1E rate inflation depending on the type and number of unspecified model items as well as different trial characteristics. We simulated a randomized, double-blind, parallel group, phase III clinical trial under the assumption that there is no treatment effect at any time point. The simulated data was analysed using different clusters, each including several MMRMs that are compatible with the imprecise pre-specification of the MMRM. T1E rates for each cluster were estimated. A significant T1E rate inflation could be shown for ambiguous model specifications with a maximum T1E rate of 7.6% [7.1%; 8.1%]. The results show that the magnitude of the T1E rate inflation depends on the type and number of unspecified model items as well as the sample size and allocation ratio. The imprecise specification of nuisance parameters may not lead to a significant T1E rate inflation. However, the results of this simulation study rather underestimate the true T1E rate inflation. In conclusion, imprecise MMRM specifications may lead to a substantial inflation of the T1E rate and can damage the ability to generate confirmatory evidence in pivotal clinical trials.


Asunto(s)
Modelos Estadísticos , Proyectos de Investigación , Humanos , Tamaño de la Muestra , Simulación por Computador
3.
Pharm Stat ; 22(5): 836-845, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37217198

RESUMEN

Formal proof of efficacy of a drug requires that in a prospective experiment, superiority over placebo, or either superiority or at least non-inferiority to an established standard, is demonstrated. Traditionally one primary endpoint is specified, but various diseases exist where treatment success needs to be based on the assessment of two primary endpoints. With co-primary endpoints, both need to be "significant" as a prerequisite to claim study success. Here, no adjustment of the study-wise type-1-error is needed, but sample size is often increased to maintain the pre-defined power. Studies that use an at-least-one concept have been proposed where study success is claimed if superiority for at least one of the endpoints is demonstrated. This is sometimes also called the dual primary endpoint concept, and an appropriate adjustment of the study-wise type-1-error is required. This concept is not covered in the European Guideline on multiplicity because study success can be claimed if one endpoint shows significant superiority, despite a possible deterioration in the other. In line with Röhmel's strategy, we discuss an alternative approach including non-inferiority hypotheses testing that avoids obvious contradictions to proper decision-making. This approach leads back to the co-primary endpoint assessment, and has the advantage that minimum requirements for endpoints can be modeled flexibly for several practical needs. Our simulations show that, if planning assumptions are correct, the proposed additional requirements improve interpretation with only a limited impact on power, that is, on sample size.


Asunto(s)
Estudios Prospectivos , Humanos , Tamaño de la Muestra , Resultado del Tratamiento
4.
Clin Infect Dis ; 73(9): e2625-e2634, 2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-32589701

RESUMEN

BACKGROUND: Asymptomatic C. difficile colonization is believed to predispose to subsequent C. difficile infection (CDI). While emerging insights into the role of the commensal microbiota in mediating colonization resistance against C. difficile have associated CDI with specific microbial components, corresponding prospectively collected data on colonization with C. difficile are largely unavailable. METHODS: C. difficile status was assessed by GDH EIA and real-time PCR targeting the toxin A (tcdA) and B (tcdB) genes. 16S V3 and V4 gene sequencing results from fecal samples of patients tested positive for C. difficile were analyzed by assessing alpha and beta diversity, LefSe, and the Piphillin functional inference approach to estimate functional capacity. RESULTS: 1506 patients were recruited into a prospective observational study (DRKS00005335) upon admission into one of five academic hospitals. 936 of them provided fecal samples on admission and at discharge and were thus available for longitudinal analysis. Upon hospital admission, 5.5% (83/1506) and 3.7% (56/1506) of patients were colonized with toxigenic (TCD) and non-toxigenic C. difficile (NTCD), respectively. During hospitalization, 1.7% (16/936) acquired TCD. Risk factors for acquisition of TCD included pre-existing lung diseases, lower GI endoscopy and antibiotics. Species protecting against hospital-related C. difficile acquisition included Gemmiger spp., Odoribacter splanchnicus, Ruminococcus bromii and other Ruminococcus spp. Metagenomic pathway analysis identified steroid biosynthesis as the most underrepresented metabolic pathway in patients who later acquire C. difficile colonization. CONCLUSIONS: Gemmiger spp., Odoribacter splanchnicus, Ruminococcus bromii and other Ruminococci were associated with a decreased risk of C. difficile acquisition. CLINICAL TRIALS REGISTRATION: DRKS00005335.


Asunto(s)
Toxinas Bacterianas , Clostridioides difficile , Infecciones por Clostridium , Microbiota , Toxinas Bacterianas/genética , Bacteroidetes , Clostridioides , Clostridioides difficile/genética , Infecciones por Clostridium/epidemiología , Heces , Humanos , Estudios Prospectivos , Factores de Riesgo , Ruminococcus
5.
Pediatr Res ; 89(4): 981-986, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32610341

RESUMEN

BACKGROUND: Dobutamine is particularly suited to treatment of haemodynamic insufficiency caused by increased peripheral vascular resistance and myocardial dysfunction in the preterm infant. Knowledge of the elimination half-life is essential to estimate the steady state when its efficacy/safety can be evaluated. METHODS: Analysis of pharmacokinetic data in ten preterm newborns treated with a new neonatal formulation of dobutamine (IMP) after screening for haemodynamic insufficiency within the first 72 h from birth. Blood samples were withdrawn at the end of IMP infusion and at a random time after the end of infusion (5 min, 15 min, 45 min, 2 h and 6 h). IMP concentration in each sample was measured by ultra-high performance liquid chromatography with electrochemical detection. RESULTS: Median duration of IMP infusion was 37.7 h (IQR 21.2). Calculated IMP half-life ranged between 3.06 and 36.1 min (median 10.6 min), leading to a time to reach the steady-state concentration between 15 min and >2 h. Adverse events were not related to IMP. CONCLUSIONS: The wide variability in dobutamine metabolism in preterm infants requires awareness about the risk of under- or overtreatment. A delay of up to 3 h might be required before drawing blood samples to evaluate the effective dose. IMPACT: Small trials suggest dobutamine as the optimal drug in the preterm infant with haemodynamic insufficiency after birth. Age-related differences in drug pharmacokinetics may result in suboptimal treatments. The lack of formal studies in preterms results in inadequate data on efficacy and safety. This study provides data on the variability of the elimination half-life of dobutamine in the very preterm infant during transitional circulation. There is a wide variation in the time to reach the plasma concentration corresponding to steady state, the moment when its efficacy/safety can be reliably evaluated. This information is crucial for planning future trials on cardiovascular support.


Asunto(s)
Dobutamina/efectos adversos , Dobutamina/farmacocinética , Hemodinámica/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Electroquímica/métodos , Cardiopatías/metabolismo , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/tratamiento farmacológico , Miocardio/patología , Seguridad del Paciente , Factores de Tiempo , Resistencia Vascular
6.
Pharm Stat ; 20(3): 675-691, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33594741

RESUMEN

The COVID-19 pandemic has manifold impacts on clinical trials. In response, drug regulatory agencies and public health bodies have issued guidance on how to assess potential impacts on ongoing clinical trials and stress the importance of a risk-assessment as a pre-requisite for modifications to the clinical trial conduct. This article presents a simulation study to assess the impact on the power of an ongoing clinical trial without the need to unblind trial data and compromise trial integrity. In the context of the CANNA-TICS trial, investigating the effect of nabiximols on reducing the total tic score of the Yale Global Tic Severity Scale (YGTSS-TTS) in patients with chronic tic disorders and Tourette syndrome, the impact of the two COVID-19 related intercurrent events handled by a treatment policy strategy is investigated using a multiplicative and additive data generating model. The empirical power is examined for the analysis of the YGTSS-TTS as a continuous and dichotomized endpoint using analysis techniques adjusted and unadjusted for the occurrence of the intercurrent event. In the investigated scenarios, the simulation studies showed that substantial power losses are possible, potentially making sample size increases necessary to retain sufficient power. However, we were also able to identify scenarios with only limited loss of power. By adjusting for the occurrence of the intercurrent event, the power loss could be diminished to different degrees in most scenarios. In summary, the presented risk assessment approach may support decisions on trial modifications like sample size increases, while maintaining trial integrity.


Asunto(s)
COVID-19/prevención & control , Cannabidiol/uso terapéutico , Simulación por Computador , Dronabinol/uso terapéutico , Salud Mental , Distanciamiento Físico , Ensayos Clínicos Controlados Aleatorios como Asunto , Proyectos de Investigación , Trastornos de Tic/tratamiento farmacológico , Tics/tratamiento farmacológico , COVID-19/psicología , COVID-19/transmisión , Cannabidiol/efectos adversos , Interpretación Estadística de Datos , Dronabinol/efectos adversos , Combinación de Medicamentos , Determinación de Punto Final , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Proyectos de Investigación/estadística & datos numéricos , Tamaño de la Muestra , Índice de Severidad de la Enfermedad , Trastornos de Tic/diagnóstico , Trastornos de Tic/psicología , Tics/diagnóstico , Tics/psicología , Factores de Tiempo , Síndrome de Tourette/tratamiento farmacológico , Síndrome de Tourette/psicología , Resultado del Tratamiento
7.
Pharm Stat ; 20(6): 1002-1016, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33908160

RESUMEN

With more and better clinical data being captured outside of clinical studies and greater data sharing of clinical studies, external controls may become a more attractive alternative to randomized clinical trials (RCTs). Both industry and regulators recognize that in situations where a randomized study cannot be performed, external controls can provide the needed contextualization to allow a better interpretation of studies without a randomized control. It is also agreed that external controls will not fully replace RCTs as the gold standard for formal proof of efficacy in drug development and the yardstick of clinical research. However, it remains unclear in which situations conclusions about efficacy and a positive benefit/risk can reliably be based on the use of an external control. This paper will provide an overview on types of external control, their applications and the different sources of bias their use may incur, and discuss potential mitigation steps. It will also give recommendations on how the use of external controls can be justified.


Asunto(s)
Sesgo , Grupos Control , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
8.
Eur Heart J ; 40(40): 3336-3341, 2019 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-31211324

RESUMEN

AIMS: The Digitalis Investigation Group (DIG) trial, the only large randomized trial of digoxin in heart failure, reported a neutral effect on mortality and a significant reduction in heart failure hospitalizations. Recent observational studies reported increased mortality with digoxin treatment. We present further analyses of the DIG trial displaying the inability to control bias in observational treatment comparisons despite extensive statistical adjustments. METHODS AND RESULTS: Forty-four percent of the 6800 patients in the DIG trial had been treated with digoxin before randomization, and half of them were randomly withdrawn from digoxin treatment. We contrast the main randomization-based result of the DIG trial with the observational non-randomized comparison of patients pre-treated or not pre-treated with digoxin. Mortality [hazard ratio (HR) 1.22, 95% confidence interval (CI) 1.12-1.34; P < 0.001] and heart failure hospitalizations (HR 1.47, 95% CI 1.33-1.61; P < 0.001) were significantly higher in patients pre-treated with digoxin even after adjustment for baseline population differences. The higher risks for both outcomes in those who had previously received digoxin persisted even if they received placebo during the trial (HR 1.24, 95% CI 1.10-1.40; P < 0.001). This sharply contradicts the neutral effect on mortality and the significant reduction in heart failure hospitalizations observed in the randomized comparison. CONCLUSION: Prescription of digoxin is an indicator of disease severity and worse prognosis, which cannot be fully accounted for by covariate adjustments in the DIG trial where patients were well-characterized. It is unlikely that weaker research approaches (observational studies of administrative data or registries) can provide more reliable estimates of the effects of cardiac glycosides.


Asunto(s)
Cardiotónicos , Digoxina , Insuficiencia Cardíaca , Sesgo , Cardiotónicos/efectos adversos , Cardiotónicos/uso terapéutico , Digoxina/efectos adversos , Digoxina/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/mortalidad , Humanos , Estudios Observacionales como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto
9.
Foot Ankle Surg ; 26(2): 146-150, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30718168

RESUMEN

Background Hallux valgus is a common diagnosis in orthopedics. Only a few studies have analyzed the effects of conservative therapy. Therefore, the current study analyzed the effect of a dynamic hallux valgus splint. Methods Seventy patients were included in this prospective randomized trial. Patients with a hallux valgus were treated using a dynamic splint or underwent no treatment. Clinical and radiological parameters were evaluated. Results We found no significant changes in hallux valgus angle, intermetatarsal I-II angle, AOFAS score, FAOS or SF-36 score between the groups. However, a significant between-group difference was found for pain during walking and running and in the FAOS subscale for pain and pain at rest at follow-up. Conclusions Wearing a dynamic hallux valgus splint does provide some pain relief in patients with a symptomatic hallux valgus, but showed no effect on hallux valgus position. Level of evidence: 1.


Asunto(s)
Hallux Valgus/terapia , Férulas (Fijadores) , Adolescente , Adulto , Anciano , Femenino , Hallux Valgus/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Dolor/fisiopatología , Manejo del Dolor , Dimensión del Dolor , Estudios Prospectivos , Carrera/fisiología , Caminata/fisiología , Adulto Joven
10.
Respir Res ; 20(1): 151, 2019 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-31299972

RESUMEN

BACKGROUND: The combination of chronic obstructive pulmonary disease (COPD) and chronic kidney disease (CKD) is associated with a higher prevalence of comorbidities and increased mortality. The impact of kidney function on patient-centered outcomes in COPD has not been evaluated. METHODS: Patients from the German COPD and Systemic Consequences - Comorbidities Network (COSYCONET) cohort COPD were analysed. CKD was diagnosed if the estimated glomerular filtration rate (eGFR) measurements were < 60 mL/min/1.73m2 at study inclusion and six month later. The effect of CKD, on comorbidities, symptoms [modified British Medical Research Council dyspnoea scale], physical capacity [six-minute walk test, and timed up and go] and St George's Respiratory Questionnaire were analysed. Restricted cubic spline models were used to evaluate a nonlinear relationship between eGFR with patient-centered outcomes, cox survival analysis was applied to evaluate mortality. RESULTS: 2274 patients were analysed, with CKD diagnosed in 161 (7.1%). Spline models adjusted for age, gender, BMI, FEV1 and cardiovascular comorbidities revealed independent associations between eGFR with modified British Medical Research Council dyspnoea scale, St George's Respiratory Questionnaire, (p < 0.001 and p = 0.011), six-minute walk test (p = 0.015) and timed up and go (p < 0.001). CKD was associated with increased mortality, independently from for other cardiovascular comorbidities (hazard ratio 2.3; p < 0.001). CONCLUSION: These data show that CKD is a relevant comorbidity in COPD patients which impacts on patient-centered outcomes and mortality. TRIAL REGISTRATION: NCT01245933.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/epidemiología , Anciano , Estudios de Cohortes , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Insuficiencia Renal Crónica/fisiopatología , Pruebas de Función Respiratoria/métodos , Prueba de Paso/métodos
11.
Nephrol Dial Transplant ; 34(7): 1171-1181, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29860340

RESUMEN

BACKGROUND: Identification and quantification of the relevant factors for death can improve patients' individual risk assessment and decision-making. We used a well-documented patient cohort (n = 892) in a renal transplant programme with protocol biopsies to establish multivariable Cox models for risk assessment at 3 and 12 months post-transplantation. METHODS: Patients transplanted between 2000 and 2007 were observed up to 11 years (total observation 5227 patient-years; median 5.9 years). Loss to follow-up was negligible (n = 15). A total of 2251 protocol biopsies and 1214 biopsies for cause were performed. All rejections and clinical borderline rejections in protocol biopsies were treated. RESULTS: Overall 10-year patient survival was 78%, with inferior survival of patients with graft loss and superior survival of patients with living-donor transplantation. Eight factors were common in the models at 3 and 12 months, including age, pre-transplant heart failure and a score of cardiovascular disease and type 2 diabetes, post-transplant urinary tract infection, treatment of rejection, new-onset heart failure, coronary events and malignancies. Additional variables of the model at 3 months included deceased donor transplantation, transplant lymphocele, BK virus nephropathy and severe infections. Graft function and graft loss were significant factors of the model at 12 months. Internal validation and validation with a separate cohort of patients (n = 349) demonstrated good discrimination of the models. CONCLUSIONS: The identified factors indicate the important areas that need special attention in the pre- and post-transplant care of renal transplant patients. On the basis of these models, we provide nomograms as a tool to weigh individual risks that may contribute to decreased survival.


Asunto(s)
Biopsia/métodos , Predicción , Rechazo de Injerto/patología , Trasplante de Riñón/efectos adversos , Riñón/patología , Sistema de Registros , Medición de Riesgo/métodos , Causas de Muerte/tendencias , Femenino , Estudios de Seguimiento , Alemania/epidemiología , Rechazo de Injerto/mortalidad , Supervivencia de Injerto , Humanos , Trasplante de Riñón/mortalidad , Masculino , Persona de Mediana Edad , Infecciones por Polyomavirus/virología , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia/tendencias
12.
Pharm Stat ; 18(6): 636-644, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31267673

RESUMEN

In confirmatory clinical trials, the prespecification of the primary analysis model is a universally accepted scientific principle to allow strict control of the type I error. Consequently, both the ICH E9 guideline and the European Medicines Agency (EMA) guideline on missing data in confirmatory clinical trials require that the primary analysis model is defined unambiguously. This requirement applies to mixed models for longitudinal data handling missing data implicitly. To evaluate the compliance with the EMA guideline, we evaluated the model specifications in those clinical study protocols from development phases II and III submitted between 2015 and 2018 to the Ethics Committee at Hannover Medical School under the German Medicinal Products Act, which planned to use a mixed model for longitudinal data in the confirmatory testing strategy. Overall, 39 trials from different types of sponsors and a wide range of therapeutic areas were evaluated. While nearly all protocols specify the fixed and random effects of the analysis model (95%), only 77% give the structure of the covariance matrix used for modeling the repeated measurements. Moreover, the testing method (36%), the estimation method (28%), the computation method (3%), and the fallback strategy (18%) are given by less than half the study protocols. Subgroup analyses indicate that these findings are universal and not specific to clinical trial phases or size of company. Altogether, our results show that guideline compliance is to various degrees poor and consequently, strict type I error rate control at the intended level is not guaranteed.


Asunto(s)
Ensayos Clínicos como Asunto/legislación & jurisprudencia , Estudios Longitudinales , Modelos Estadísticos , Proyectos de Investigación , Ensayos Clínicos como Asunto/métodos , Interpretación Estadística de Datos , Europa (Continente) , Humanos
14.
Blood ; 127(19): 2289-97, 2016 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-26912467

RESUMEN

Neutralizing autoantibodies against factor VIII (FVIII), also called FVIII inhibitors, are the cause of acquired hemophilia A (AHA). They are quantified in the Bethesda assay or Nijmegen-modified Bethesda assay by their ability to neutralize FVIII in normal human plasma. However, FVIII inhibitors do not represent the whole spectrum of anti-FVIII autoantibodies. Here, we studied isotypes, immunoglobulin G subclasses, and apparent affinities of anti-FVIII autoantibodies to assess their prognostic value for the outcome in AHA. We analyzed baseline samples from patients enrolled in the prospective GTH-AH 01/2010 study. Our data suggest that anti-FVIII immunoglobulin A (IgA) autoantibodies are predictors of poor outcome in AHA. Anti-FVIII IgA-positive patients achieved partial remission similar to anti-FVIII IgA-negative patients but had a higher risk of subsequent recurrence. Consequently, IgA-positive patients achieved complete remission less frequently (adjusted hazard ratio [aHR], 0.35; 95% confidence interval [CI], 0.18-0.68; P < .01) and had a higher risk of death (aHR, 2.62; 95% CI, 1.11-6.22; P < .05). Anti-FVIII IgA was the strongest negative predictor of recurrence-free survival after achieving partial remission and remained significant after adjustment for baseline demographic and clinical characteristics. In conclusion, anti-FVIII IgA represents a potential novel biomarker that could be useful to predict prognosis and tailor immunosuppressive treatment of AHA.


Asunto(s)
Autoanticuerpos/sangre , Factor VIII/antagonistas & inhibidores , Hemofilia A , Inmunoglobulina A/sangre , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Femenino , Hemofilia A/sangre , Hemofilia A/mortalidad , Hemofilia A/terapia , Humanos , Masculino , Persona de Mediana Edad , Tasa de Supervivencia
15.
Am J Respir Crit Care Med ; 195(2): 189-197, 2017 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-27532739

RESUMEN

RATIONALE: Knowledge about the prevalence of objectively assessed peripheral artery disease (PAD) and its clinical relevance in patients with chronic obstructive pulmonary disease (COPD) is scarce. OBJECTIVES: We aimed to: (1) assess the prevalence of PAD in COPD compared with distinct control groups; and (2) study the association between PAD and functional capacity as well as health status. METHODS: The ankle-brachial index was used to diagnose PAD (ankle-brachial index ≤ 0.9). The 6-minute-walk distance, health status (St. George's Respiratory Questionnaire), COPD Assessment Test, and EuroQol-5-Dimensions were assessed in patients enrolled in the German COPD and Systemic Consequences-Comorbidities Network cohort study. Control groups were derived from the Study of Health in Pomerania. MEASUREMENTS AND MAIN RESULTS: A total of 2,088 patients with COPD (61.1% male; mean [SD] age, 65.3 [8.2] years, GOLD (Global Initiative for Chronic Obstructive Lung Disease) stages I-IV: 9.4, 42.5, 37.5, and 10.5%, respectively) were included, of which 184 patients (8.8%; GOLD stage I-IV: 5.1, 7.4, 11.1, and 9.5%, respectively, vs. 5.9% in patients with GOLD stage 0 in the COPD and Systemic Consequences-Comorbidities Network) had PAD. In the Study of Health in Pomerania, PAD ranged from 1.8 to 4.2%. Patients with COPD with PAD had a significantly shorter 6-minute-walk distance (356 [108] vs. 422 [103] m, P < 0.001) and worse health status (St. George's Respiratory Questionnaire: 49.7 [20.1] vs. 42.7 [20.0] points, P < 0.001; COPD Assessment Test: 19.6 [7.4] vs. 17.9 [7.4] points, P = 0.004; EuroQol-5-Dimensions visual analog scale: 51.2 [19.0] vs. 57.2 [19.6], P < 0.001). Differences remained significant after correction for several confounders. CONCLUSIONS: In a large cohort of patients with COPD, 8.8% were diagnosed with PAD, which is higher than the prevalence in control subjects without COPD. PAD was associated with a clinically relevant reduction in functional capacity and health status.


Asunto(s)
Enfermedad Arterial Periférica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Actividades Cotidianas , Anciano , Índice Tobillo Braquial , Comorbilidad , Femenino , Estado de Salud , Humanos , Estudios Longitudinales , Masculino , Enfermedad Arterial Periférica/epidemiología , Prevalencia , Estudios Prospectivos , Enfermedad Pulmonar Obstructiva Crónica/epidemiología
16.
Pharm Stat ; 17(4): 329-341, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29667367

RESUMEN

A common challenge for the development of drugs in rare diseases and special populations, eg, paediatrics, is the small numbers of patients that can be recruited into clinical trials. Extrapolation can be used to support development and licensing in paediatrics through the structured integration of available data in adults and prospectively generated data in paediatrics to derive conclusions that support licensing decisions in the target paediatric population. In this context, Bayesian analyses have been proposed to obtain formal proof of efficacy of a new drug or therapeutic principle by using additional information (data, opinion, or expectation), expressed through a prior distribution. However, little is said about the impact of the prior assumptions on the evaluation of outcome and prespecified strategies for decision-making as required in the regulatory context. On the basis of examples, we explore the use of data-based Bayesian meta-analytic-predictive methods and compare these approaches with common frequentist and Bayesian meta-analysis models. Noninformative efficacy prior distributions usually do not change the conclusions irrespective of the chosen analysis method. However, if heterogeneity is considered, conclusions are highly dependent on the heterogeneity prior. When using informative efficacy priors based on previous study data in combination with heterogeneity priors, these may completely determine conclusions irrespective of the data generated in the target population. Thus, it is important to understand the impact of the prior assumptions and ensure that prospective trial data in the target population have an appropriate chance, to change prior belief to avoid trivial and potentially erroneous conclusions.


Asunto(s)
Teorema de Bayes , Ensayos Clínicos como Asunto/estadística & datos numéricos , Interpretación Estadística de Datos , Probabilidad , Ensayos Clínicos como Asunto/métodos , Humanos , Metaanálisis como Asunto
17.
Blood ; 125(7): 1091-7, 2015 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-25525118

RESUMEN

Acquired hemophilia A (AHA) is caused by autoantibodies against factor VIII (FVIII). Immunosuppressive treatment (IST) results in remission of disease in 60% to 80% of patients over a period of days to months. IST is associated with frequent adverse events, including infections as a leading cause of death. Predictors of time to remission could help guide IST intensity but have not been established. We analyzed prognostic factors in 102 prospectively enrolled patients treated with a uniform IST protocol. Partial remission (PR; defined as no active bleeding, FVIII restored >50 IU/dL, hemostatic treatment stopped >24 hours) was achieved by 83% of patients after a median of 31 days (range 7-362). Patients with baseline FVIII <1 IU/dL achieved PR less often and later (77%, 43 days) than patients with ≥1 IU/dL (89%, 24 days). After adjustment for other baseline characteristics, low FVIII remained associated with a lower rate of PR (hazard ratio 0.52, 95% confidence interval 0.33-0.81, P < .01). In contrast, PR achieved on steroids alone within ≤21 days was more common in patients with FVIII ≥1 IU/dL and inhibitor concentration <20 BU/mL (odds ratio 11.2, P < .0001). Low FVIII was also associated with a lower rate of complete remission and decreased survival. In conclusion, presenting FVIII and inhibitor concentration are potentially useful to tailor IST in AHA.


Asunto(s)
Hemofilia A , Inmunosupresores/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Autoanticuerpos/efectos adversos , Factor VIII/análisis , Factor VIII/inmunología , Femenino , Hemofilia A/diagnóstico , Hemofilia A/mortalidad , Hemofilia A/terapia , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Inducción de Remisión , Análisis de Supervivencia , Resultado del Tratamiento
18.
Respir Res ; 18(1): 60, 2017 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-28416015

RESUMEN

BACKGROUND: Alpha-1-Antitrypsin Deficiency (AATD) is an economically unexplored genetic disease. METHODS: Direct and indirect costs (based on self-reported information on healthcare utilization) and health-related quality of life (HRQL, as assessed by SGRQ, CAT, and EQ-5D-3 L) were compared between 131 AATD patients (106 with, 25 without augmentation therapy (AT)) and 2,049 COPD patients without AATD participating in the COSYCONET COPD cohort. The medication costs of AT were excluded from all analyses to reveal differences associated with morbidity profiles. The association of AATD (with/without AT) with costs or HRQL was examined using generalized linear regression modelling (GLM) adjusting for age, sex, GOLD grade, BMI, smoking status, education and comorbidities. RESULTS: Adjusted mean direct annual costs were €6,099 in AATD patients without AT, €7,117 in AATD patients with AT (excluding costs for AT), and €7,460 in COPD patients without AATD. AATD with AT was significantly associated with higher outpatient (+273%) but lower inpatient (-35%) and medication costs (-10%, disregarding AT) compared with COPD patients without AATD. There were no significant differences between groups regarding indirect costs and HRQL. CONCLUSION: Apart from AT costs, AATD patients tended to have lower, though not significant, overall costs and similar HRQL compared to COPD patients without AATD. AT was not associated with lower costs or higher HRQL. TRIAL REGISTRATION: NCT01245933.


Asunto(s)
Costo de Enfermedad , Costos de la Atención en Salud/estadística & datos numéricos , Enfermedad Pulmonar Obstructiva Crónica/economía , Enfermedad Pulmonar Obstructiva Crónica/psicología , Calidad de Vida/psicología , Deficiencia de alfa 1-Antitripsina/economía , Deficiencia de alfa 1-Antitripsina/psicología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Comorbilidad , Femenino , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Factores de Riesgo , Distribución por Sexo , Adulto Joven , Deficiencia de alfa 1-Antitripsina/epidemiología
19.
Respir Res ; 18(1): 171, 2017 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-28915894

RESUMEN

BACKGROUND: Alpha-1-antitrypsin deficiency (AATD) is a rare inherited condition caused by mutations of the SERPINA1 gene that is associated with the development of a COPD like lung disease. The comorbidities in patients with AATD-related lung diseases are not well defined. The aim of this study was to analyze the clinical phenotype of AATD patients within the German COPD cohort study COSYCONET ("COPD and SYstemic consequences-COmorbidities NETwork") cohort focusing on the distribution of comorbidities. METHOD AND RESULTS: The data from 2645 COSYCONET patients, including 139 AATD patients (110 with and 29 without augmentation therapy), were analyzed by descriptive statistics and regression analyses. We found significantly lower prevalence of cardiovascular comorbidities in AATD patients as compared to non-AATD COPD patients. After correction for age, pack years, body mass index, and sex, the differences were still significant for coronary artery disease (p = 0.002) and the prevalence of peripheral artery disease as determined by an ankle-brachial-index <= 0.9 (p = 0.035). Also the distribution of other comorbidities such as bronchiectasis differed between AATD and non-deficient COPD. CONCLUSION: AATD is associated with a lower prevalence of cardiovascular disease, the underlying mechanisms need further investigation.


Asunto(s)
Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Deficiencia de alfa 1-Antitripsina/diagnóstico , Deficiencia de alfa 1-Antitripsina/epidemiología , Anciano , Enfermedades Cardiovasculares/genética , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , alfa 1-Antitripsina/genética , Deficiencia de alfa 1-Antitripsina/genética
20.
Liver Int ; 37(2): 196-204, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27428078

RESUMEN

BACKGROUND & AIMS: Identifying advanced fibrosis in chronic hepatitis delta patients and thus in need of urgent treatment is crucial. To avoid liver biopsy, non-invasive fibrosis scores may be helpful but have not been evaluated for chronic hepatitis delta yet. METHODS: We evaluated eight non-invasive fibrosis scores in 100 HDV RNA-positive patients with available central histological reading. New cut-off values were calculated by using Receiver Operating Characteristics and Youden indexes. Predictors for the presence of ISHAK F3-6 were revealed by t-tests or Mann-Whitney tests. RESULTS: None of the tested scores had an area under the curve (AUROC) > 0.8 and performed according to our predefined requirements of a sensitivity of >80% and a positive predictive value (PPV) >90% - even after adaption. However, the ELF score was able to identify advanced fibrosis with a high sensitivity (93%) and PPV (81%), but relies on expensive extracellular matrix markers with bad availability in many endemic regions of HDV. Thus, we developed a novel non-invasive approach and identified low cholinesterase (P=.002), low albumin (P=.041), higher gamma glutamyl transferase, as well as older age (P<.001) as predictors of fibrosis resulting in the Delta Fibrosis Score (DFS). The DFS performed with a sensitivity of 85% and PPV of 93% with an AUROC of 0.87. CONCLUSIONS: Existing non-invasive fibrosis scores are either impracticable or do not perform well in chronic hepatitis delta patients. However, the new Delta Fibrosis Score is the first non-invasive fibrosis score specifically developed for chronic hepatitis delta and requires only standard parameters.


Asunto(s)
Hepatitis D Crónica/complicaciones , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/virología , Hígado/patología , Adulto , Biomarcadores/sangre , Biopsia , Ensayos Clínicos Fase II como Asunto , Progresión de la Enfermedad , Femenino , Alemania , Hepatitis D Crónica/patología , Virus de la Hepatitis Delta , Humanos , Cirrosis Hepática/patología , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Valor Predictivo de las Pruebas , Curva ROC , Ensayos Clínicos Controlados Aleatorios como Asunto , Índice de Severidad de la Enfermedad , Adulto Joven , gamma-Glutamiltransferasa/sangre
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