Block-Coordinate Frank-Wolfe Optimization for Structural SVMs

We propose a randomized block-coordinate variant of the classic Frank-Wolfe algorithm for convex optimization with block-separable constraints. Despite its lower iteration cost, we show that it achieves a similar convergence rate in duality gap as the full Frank-Wolfe algorithm. We also show that, when applied to the dual structural support vector machine (SVM) objective, this yields an online algorithm that has the same low iteration complexity as primal stochastic subgradient methods. However, unlike stochastic subgradient methods, the block-coordinate Frank-Wolfe algorithm allows us to compute the optimal step-size and yields a computable duality gap guarantee. Our experiments indicate that this simple algorithm outperforms competing structural SVM solvers.Comment: Appears in Proceedings of the 30th International Conference on Machine Learning (ICML 2013). 9 pages main text + 22 pages appendix. Changes from v3 to v4: 1) Re-organized appendix; improved & clarified duality gap proofs; re-drew all plots; 2) Changed convention for Cf definition; 3) Added weighted averaging experiments + convergence results; 4) Clarified main text and relationship with appendi

Inpatient hospital costs of febrile neutropenia as a consequence of chemotherapy for breast cancer and non-Hodgkin lymphoma in Switzerland

Febrile neutropenia (FN) can be a serious complication of chemotherapy (CHT), increasing mortality risk and healthcare costs. Incidence and inpatient hospital costs of FN in Switzerland are currently not reported. The study aimed to: 1. Estimate the number of CHT induced FN-related hospitalizations. 2. Assess inpatient hospital costs per FN event in Switzerland

Cost-effectiveness of dabigatran for stroke prevention in atrial fibrillation in Switzerland

Objectives: Atrial fibrillation is a major risk factor for ischemic stroke and anticoagulation therapy is indicated to reduce risk. Dabigatran is a new oral anticoagulant that does not require INR monitoring. This study evaluated the cost-effectiveness of dabigatran versus vitamin K antagonists for stroke prevention in atrial fibrillation in Switzerland. Methods: A Markov model simulating the course of treatment and occurrence of clinical events in two treatment arms over the lifetime of patients was adapted to the Swiss context. The adaptation included the cost of anticoagulation therapy and clinical events in Switzerland. The cost of inpatient care was estimated on data of all inpatient hospital stays in 2008. The calculation of outpatient care costs was based on peer reviewed studies, expert interviews and local tariffs. Results: Patients treated with dabigatran had a higher life expectancy and experienced more quality adjusted life years (QALY) while incurring higher costs than patients treated with vitamin K antagonists. The estimated incremental cost-effectiveness ratio (ICER) was CHF 25,108.‒ per QALY with 110 mg and CHF 9,702 per QALY with 150 mg of dabigatran. A sequential dosage scheme, in which 150 mg are administered up to the age of 80 years and 110 mg thereafter, resulted in an ICER of CHF 10,215 per QALY. A sensitivity analysis confirmed that these results are robust. Conclusions: Dabigatran can be considered cost-effective in comparison with vitamin K antagonists in the Swiss context. The higher drug cost of dabigatran is compensated by savings in INR monitoring, lower cost of clinical events and QALY-gains

Herausforderungen beim Messen von Qualität

Die Patientensicherheit wird zu einem grossen Teil durch gute Qualität der Leistungserbringung erreicht. Daher gilt es, Qualität zu überprüfen und dort, wo Defizite identifiziert werden, Massnahmen zur Verbesserung einzuleiten. Diese vermeintlich klare und einfach umzusetzende Aufgabe birgt jedoch einige Herausforderungen

Real-world expenditures and survival time after CAR-T treatment for large B-cell lymphoma in Switzerland: a retrospective study using insurance claims data

AIM OF THE STUDY: Newly approved therapies with high and uncertain budget impact pose challenges to public health care systems worldwide. One recent example is chimeric antigen receptor T cell (CAR-T) therapies for adults with large B-cell lymphoma (LBCL). This study’s primary objective is to examine the expenditures of Swiss public payers before, during, and after CAR-T cell therapy in patients with LBCL aged ≥30 years. Its secondary objective is to analyse 24-month survival rates. METHODS: This retrospective observational data analysis used the administrative databases of the Swiss health insurers Concordia, CSS, Groupe Mutuel, Helsana, ÖKK, Sanitas, SWICA, Sympany, and Visana. These health insurers or groups provide mandatory health insurance to approximately 78% of Swiss residents in 2021. Using the relevant procedure codes, we identified CAR-T therapies administered between October 2018 (first approval) and June 2021 (treatment identification cut-off). Patients aged <30 years were excluded because they might be treated for pediatric acute lymphoblastic leukaemia. Expenditures were categorised as pre-infusion, peri-infusion (excluding CAR-T therapy acquisition costs), and post-infusion based on the time of service provision. Overall survival rates were estimated using the Kaplan–Meier method. RESULTS: This study identified 81 patients aged ≥30 years, with a median follow-up period for censored observations of 27 months (interquartile range: 21–31 months). The median age group was 70–74, and 60% of patients were male. Mean healthcare expenditures per patient per month amounted to CHF 8,115–22,564 pre-infusion, CHF 38,490 peri-infusion, and CHF 5,068–11,342 post-infusion. For the total peri- and post-infusion period (i.e. 1-month before infusion to 23 months after infusion), mean healthcare expenditures amounted to CHF 215,737. The 24-month overall survival rate was 48% (95% confidence interval: 38–61%). CONCLUSIONS: Healthcare expenditures after CAR-T cell infusion are relatively high compared to previous estimates of patients with LBCL in the last year of treatment. Further research is needed to understand the drivers behind these post-infusion expenditures. Especially, clinical data should be used to assess the time until disease progression. The analysis of 24-month overall survival is consistent with results from the pivotal trials. Our findings stress the importance of post-approval studies to monitor real-world expenditures and outcomes related to innovative therapies

Cost-effectiveness of functional cardiac imaging in the diagnostic work-up of coronary heart disease

The aim of this study was to assess the cost-effectiveness of eight common diagnostic work-up strategies for coronary heart disease (CHD) in patients with stable angina symptoms in Switzerland. Methods and results A decision analytical model was used to perform a cost-effectiveness comparison of eight common multitest strategies to diagnose CHD using combinations of four diagnostic techniques: exercise treadmill test (ETT), single-photon emission computed tomography (SPECT), cardiac magnetic resonance imaging (CMR), and coronary angiography (CA). We used a Markov state transition model to extrapolate the results over a life-time horizon, from a third-party payer perspective. We used a CHD prevalence rate of 39% in patients and a base-case scenario with 60-year-old male patients with intermediate symptom severity Canadian Cardiovascular Society grading of angina pectoris 2 and at least one cardiovascular (CV) risk factor but without a history of myocardial infarction and without need for revascularization. Among the eight work-up strategies, one strategy was dominant, i.e. least costly and most effective: ETT followed by CMR if the ETT result was inconclusive and then CA if the CMR result was positive or inconclusive. The CMR features a favourable balance between false-negative diagnoses, associated with an elevated risk of CV events, and false-positive diagnoses, leading to unnecessary CA and related mortality. Key parameters guiding the diagnostic strategy are the prevalence of CHD in patients with angina symptoms and the diagnostic costs of CA and CMR

Health literacy and outpatient physician visits in Switzerland

Health literacy has been identified as an important contributor to health inequalities in industrialised countries (Kickbusch, 2002). Health literacy can be defined as “the capacity to obtain, interpret and understand basic health information and services and the competence to use such information and services to enhance health” (United States Department of Health and Human Services, 2000). Limited health literacy is associated with poor health (DeWalt et al., 2004) and high health care cost (Eichler et al., 2009). One possible explanation for these disparities is different health service utilisation. It has been shown that people with limited health literacy use diagnostic interventions less frequently (Bennett et al., 2009; Garbers, 2004; Guerra et al., 2005; Peterson et al., 2007; White et al., 2008), have lower immunisation rates (Bennett et al., 2009; Howard et al., 2005; Scott et al., 2002; Sudore et al., 2006), are more likely to be admitted to emergency departments (Cho et al., 2008; Howard et al., 2005; Murray et al., 2009), and have more inpatient hospital stays (Cho et al., 2008; DeWalt et al., 2004; Hope et al., 2004; Paasche-Orlow et al., 2005). Outpatient physician visits, however, are not well covered in the literature (Baker et al., 2004) and most studies analysing service utilisation are limited to very specific patient groups. Our study investigates the association between health literacy and outpatient physician visits based on data from a Swiss population survey