Impact of gender: Rivaroxaban for patients with atrial fibrillation in the XANTUS real-world prospective study.

BACKGROUND: The XANTUS study (NCT01606995) demonstrated low rates of stroke and major bleeding in patients with atrial fibrillation (AF) receiving rivaroxaban in clinical practice for the prevention of thromboembolic events (N = 6784). HYPOTHESIS: Because previous real-world studies have not reported gender-dependent responses to rivaroxaban treatment, this sub-analysis of the XANTUS study investigated the effect of gender on outcomes. METHODS: The centrally adjudicated outcomes were compared between genders. Primary outcomes were major bleeding and all-cause death. Secondary outcomes included symptomatic thromboembolic events. Multivariable Cox regression analysis was performed to assess the effect of risk factors on outcomes between genders. RESULTS: A total of 2765 female and 4016 male patients were included in the analysis. Baseline characteristics were generally similar. No nominally significant interaction between gender and risk factors for the study outcomes was observed. Rates of major bleeding, all-cause death and symptomatic thromboembolic events in patients with non-valvular AF receiving rivaroxaban for stroke prevention were similar in men and women; no significant differences in risk factors for these outcomes were observed between genders. CONCLUSIONS: Further research is needed to better characterize the relative importance of different risk factors on outcomes in men vs women and to determine whether gender differences exist in patients treated with non-vitamin K antagonist oral anticoagulants.

Impact of Switching From a Vitamin K Antagonist to Rivaroxaban on Satisfaction With Anticoagulation Therapy: The XANTUS-ACTS Substudy.

BACKGROUND: The efficacy, safety, and ease of use of rivaroxaban may reduce anticoagulation-treatment burden and improve nonvalvular atrial fibrillation (NVAF) patient satisfaction compared with vitamin K antagonists (VKAs). HYPOTHESIS: Transitioning from a VKA to rivaroxaban improves treatment satisfaction in routine practice. METHODS: Xarelto for Prevention of Stroke in Patients With Atrial Fibrillation (XANTUS) is a prospective, noninterventional study in patients with NVAF prescribed rivaroxaban for prevention of stroke in routine practice. Patients receiving a VKA 4 weeks prior to the initial XANTUS study visit and switched to rivaroxaban were asked to complete the Anti-Clot Treatment Scale (ACTS). Changes from the initial visit to the first follow-up visit at ∼ 3 months (corresponding to a comparison of rivaroxaban vs prior VKA) for ACTS burden and benefit scores were calculated using and reported as least squared mean differences (LSMDs) with 95% confidence intervals (CIs). RESULTS: The study included 1291 NVAF patients with prior VKA treatment. The mean baseline ACTS burden and benefit scores were 50.51 ± 8.42 and 10.30 ± 2.70, respectively. After ∼ 3 months of rivaroxaban treatment, LSMDs were 4.38 points (95% CI: 2.53-6.22, P < 0.0001) for the burden and 1.01 points (95% CI: 0.27-1.75, P = 0.0075) for the benefit score. Fifty-four percent and 48% of patients reported experiencing at least a minimally important clinical difference in burden and benefit scores, respectively. CONCLUSIONS: Within this XANTUS cohort, switching from a VKA to rivaroxaban yielded statistically and clinically significant improvements in ACT burden and benefit scores.

XANTUS: a real-world, prospective, observational study of patients treated with rivaroxaban for stroke prevention in atrial fibrillation.

AIMS: Although non-vitamin K antagonist oral anticoagulants are recommended for stroke prevention in patients with non-valvular atrial fibrillation (NVAF) based on clinical trial results, there is a need for safety and efficacy data from unselected patients in everyday clinical practice. XANTUS investigated the safety and efficacy of the Factor Xa inhibitor rivaroxaban in routine clinical use in the NVAF setting. METHODS AND RESULTS: Consecutive consenting patients with NVAF newly started on rivaroxaban were eligible and were followed up at ∼3-month intervals for 1 year, or for at least 30 days after permanent discontinuation. All adverse events (AEs) were recorded as AEs or serious AEs; major outcomes (including major bleeding, symptomatic thromboembolic events [stroke, systemic embolism, transient ischaemic attack, and myocardial infarction], and all-cause death) were centrally adjudicated. There were 6784 patients treated with rivaroxaban at 311 centres in Europe, Israel, and Canada. Mean patient age was 71.5 years (range 19-99), 41% were female, and 9.4% had documented severe or moderate renal impairment (creatinine clearance <50 mL/min). The mean CHADS2 and CHA2DS2-VASc scores were 2.0 and 3.4, respectively; 859 (12.7%) patients had a CHA2DS2-VASc score of 0 or 1. The mean treatment duration was 329 days. Treatment-emergent major bleeding occurred in 128 patients (2.1 events per 100 patient-years), 118 (1.9 events per 100 patient-years) died, and 43 (0.7 events per 100 patient-years) suffered a stroke. CONCLUSION: XANTUS is the first international, prospective, observational study to describe the use of rivaroxaban in a broad NVAF patient population. Rates of stroke and major bleeding were low in patients receiving rivaroxaban in routine clinical practice. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov: NCT01606995.

A case study using the PrOACT-URL and BRAT frameworks for structured benefit risk assessment.

While benefit-risk assessment is a key component of the drug development and maintenance process, it is often described in a narrative. In contrast, structured benefit-risk assessment builds on established ideas from decision analysis and comprises a qualitative framework and quantitative methodology. We compare two such frameworks, applying multi-criteria decision-analysis (MCDA) within the PrOACT-URL framework and weighted net clinical benefit (wNCB), within the BRAT framework. These are applied to a case study of natalizumab for the treatment of relapsing remitting multiple sclerosis. We focus on the practical considerations of applying these methods and give recommendations for visual presentation of results. In the case study, we found structured benefit-risk analysis to be a useful tool for structuring, quantifying, and communicating the relative benefit and safety profiles of drugs in a transparent, rational and consistent way. The two frameworks were similar. MCDA is a generic and flexible methodology that can be used to perform a structured benefit-risk in any common context. wNCB is a special case of MCDA and is shown to be equivalent to an extension of the number needed to treat (NNT) principle. It is simpler to apply and understand than MCDA and can be applied when all outcomes are measured on a binary scale.

Stress-induced hyperglycaemia and venous thromboembolism following total hip or total knee arthroplasty: analysis from the RECORD trials.

Stress-induced hyperglycaemia is common during orthopaedic surgery. In addition, hyperglycaemia activates coagulation. The aim of the study was to assess whether stress-induced hyperglycaemia is associated with symptomatic or asymptomatic venous thromboembolism (VTE) following orthopaedic surgery. We performed post-hoc analyses in the four RECORD studies (REgulation of Coagulation in major Orthopaedic surgery reducing the Risk of Deep venous thrombosis and pulmonary embolism). Separate analyses were performed for patients undergoing elective total hip or knee replacement. Outcome measures were symptomatic VTE and "total VTE" (defined as the composite of symptomatic VTE, asymptomatic DVT assessed by per protocol venography and all cause mortality). Glucose levels were measured pre-op and 6 hours post-op, categorised into quartiles, based on the distribution in the respective cohorts. The influence of glucose, adjusted for body mass index, age, gender and diabetes mellitus on VTE was assessed by logistic regression analyses. A total of 12,383 patients were eligible for assessment of symptomatic VTE, and 8,512 patients were eligible for assessment of total VTE. Increased glucose levels after total hip replacement were associated with total VTE; adjusted odds ratio (OR) highest versus lowest quartile 1.9 (95% confidence interval [CI] 1.3 to 3.0). Furthermore, increase in glucose levels during total hip replacement was associated with total VTE (OR highest versus lowest quartile 1.8 (95%CI 1.2 to 2.8). This was not observed in patients undergoing total knee replacement, probably due to differences in the applied surgical procedures.

Collection of annotated data in a clinical validation study for alarm algorithms in intensive care--a methodologic framework.

INTRODUCTION: Monitoring of physiologic parameters in critically ill patients is currently performed by threshold alarm systems with high sensitivity but low specificity. As a consequence, a multitude of alarms are generated, leading to an impaired clinical value of these alarms due to reduced alertness of the intensive care unit (ICU) staff. To evaluate a new alarm procedure, we currently generate a database of physiologic data and clinical alarm annotations. METHODS: Data collection is taking place at a 12-bed medical ICU. Patients with monitoring of at least heart rate, invasive arterial blood pressure, and oxygen saturation are included in the study. Numerical physiologic data at 1-second intervals, monitor alarms, and alarm settings are extracted from the surveillance network. Bedside video recordings are performed with network surveillance cameras. RESULTS: Based on the extracted data and the video recordings, alarms are clinically annotated by an experienced physician. The alarms are categorized according to their technical validity and clinical relevance by a taxonomy system that can be broadly applicable. Preliminary results showed that only 17% of the alarms were classified as relevant, and 44% were technically false. DISCUSSION: The presented system for collecting real-time bedside monitoring data in conjunction with video-assisted annotations of clinically relevant events is the first allowing the assessment of 24-hour periods and reduces the bias usually created by bedside observers in comparable studies. It constitutes the basis for the development and evaluation of "smart" alarm algorithms, which may help to reduce the number of alarms at the ICU, thereby improving patient safety.

Intensive care unit alarms--how many do we need?

OBJECTIVE: To validate cardiovascular alarms in critically ill patients in an experimental setting by generating a database of physiologic data and clinical alarm annotations, and report the current rate of alarms and their clinical validity. Currently, monitoring of physiologic parameters in critically ill patients is performed by alarm systems with high sensitivity, but low specificity. As a consequence, a multitude of alarms with potentially negative impact on the quality of care is generated. DESIGN: Prospective, observational, clinical study. SETTING: Medical intensive care unit of a university hospital. DATA SOURCE: Data from different medical intensive care unit patients were collected between January 2006 and May 2007. MEASUREMENTS AND MAIN RESULTS: Physiologic data at 1-sec intervals, monitor alarms, and alarm settings were extracted from the surveillance network. Video recordings were annotated with respect to alarm relevance and technical validity by an experienced physician. During 982 hrs of observation, 5934 alarms were annotated, corresponding to six alarms per hour. About 40% of all alarms did not correctly describe the patient condition and were classified as technically false; 68% of those were caused by manipulation. Only 885 (15%) of all alarms were considered clinically relevant. Most of the generated alarms were threshold alarms (70%) and were related to arterial blood pressure (45%). CONCLUSION: This study used a new approach of off-line, video-based physician annotations, showing that even with modern monitoring systems most alarms are not clinically relevant. As the majority of alarms are simple threshold alarms, statistical methods may be suitable to help reduce the number of false-positive alarms. Our study is also intended to develop a reference database of annotated monitoring alarms for further application to alarm algorithm research.

Smart alarms from medical devices in the OR and ICU.

Alarms in medical devices are a matter of concern in critical and perioperative care. The high rate of false alarms is not only a nuisance for patients and caregivers, but can also compromise patient safety and effectiveness of care. The development of alarm systems has lagged behind the technological advances of medical devices over the last 20 years. From a clinical perspective, major improvements in alarm algorithms are urgently needed. This review gives an overview of the current clinical situation and the underlying problems, and discusses different methods from statistics and computational science and their potential for clinical application. Some examples of the application of new alarm algorithms to clinical data are presented.

Alarm algorithms in critical care monitoring.

The alarms of medical devices are a matter of concern in critical and perioperative care. The frequent false alarms not only are a nuisance for patients and caregivers but can also compromise patient safety and effectiveness of care. The development of alarm systems has lagged behind the technological advances of medical devices over the last 20 years. From a clinical perspective, major improvements of alarm algorithms are urgently needed. We give an overview of the current clinical situation and the underlying problems and discuss different methods from statistics and computational science and their potential for clinical application.