Impact of preoperative risk factors on morbidity after esophagectomy: is there room for improvement?

BACKGROUND: Despite progress in multidisciplinary treatment of esophageal cancer, oncologic esophagectomy is still the cornerstone of therapeutic strategies. Several scoring systems are used to predict postoperative morbidity, but in most cases they identify nonmodifiable parameters. The aim of this study was to identify potentially modifiable risk factors associated with complications after oncologic esophagectomy. METHODS: All consecutive patients with complete data sets undergoing oncologic esophagectomy in our department during 2001-2011 were included in this study. As potentially modifiable risk factors we assessed nutritional status depicted by body mass index (BMI) and preoperative serum albumin levels, excessive alcohol consumption, and active smoking. Postoperative complications were graded according to a validated 5-grade system. Univariate and multivariate analyses were used to identify preoperative risk factors associated with the occurrence and severity of complications. RESULTS: Our series included 93 patients. Overall morbidity rate was 81 % (n = 75), with 56 % (n = 52) minor complications and 18 % (n = 17) major complications. Active smoking and excessive alcohol consumption were associated with the occurrence of severe complications, whereas BMI and low preoperative albumin levels were not. The simultaneous presence of two or more of these risk factors significantly increased the risk of postoperative complications. CONCLUSIONS: A combination of malnutrition, active smoking and alcohol consumption were found to have a negative impact on postoperative morbidity rates. Therefore, preoperative smoking and alcohol cessation counseling and monitoring and improving the nutritional status are strongly recommended.

Which screening strategy using BMD measurements would be most cost effective for hip fracture prevention in elderly women? A decision analysis based on a Markov model.

INTRODUCTION: Hip fractures are responsible for excessive mortality, decreasing the 5-year survival rate by about 20%. From an economic perspective, they represent a major source of expense, with direct costs in hospitalization, rehabilitation, and institutionalization. The incidence rate sharply increases after the age of 70, but it can be reduced in women aged 70-80 years by therapeutic interventions. Recent analyses suggest that the most efficient strategy is to implement such interventions in women at the age of 70 years. As several guidelines recommend bone mineral density (BMD) screening of postmenopausal women with clinical risk factors, our objective was to assess the cost-effectiveness of two screening strategies applied to elderly women aged 70 years and older. METHODS: A cost-effectiveness analysis was performed using decision-tree analysis and a Markov model. Two alternative strategies, one measuring BMD of all women, and one measuring BMD only of those having at least one risk factor, were compared with the reference strategy "no screening". Cost-effectiveness ratios were measured as cost per year gained without hip fracture. Most probabilities were based on data observed in EPIDOS, SEMOF and OFELY cohorts. RESULTS: In this model, which is mostly based on observed data, the strategy "screen all" was more cost effective than "screen women at risk." For one woman screened at the age of 70 and followed for 10 years, the incremental (additional) cost-effectiveness ratio of these two strategies compared with the reference was 4,235 euros and 8,290 euros, respectively. CONCLUSION: The results of this model, under the assumptions described in the paper, suggest that in women aged 70-80 years, screening all women with dual-energy X-ray absorptiometry (DXA) would be more effective than no screening or screening only women with at least one risk factor. Cost-effectiveness studies based on decision-analysis trees maybe useful tools for helping decision makers, and further models based on different assumptions should be performed to improve the level of evidence on cost-effectiveness ratios of the usual screening strategies for osteoporosis.

Alcohol and relatively pure cannabis use, but not schizotypy, are associated with cognitive attenuations

Elevated schizotypy relates to similar cognitive attenuations as seen in psychosis and cannabis/polydrug use. Also, in schizotypal populations cannabis and polydrug (including licit drug) use are enhanced.These cognitive attenuations may therefore either be a behavioral marker of psychotic (-like) symptoms or the consequence of enhanced drug use in schizotypal populations.To elucidate this, we investigated the link between cognitive attenuation and cannabis use in largely pure cannabis users (35) and non-using controls (48), accounting for the potential additional influence of both schizotypy and licit drug use (alcohol, nicotine). Cognitive attenuations commonly seen in psychosis were associated with cannabis and alcohol use, but not schizotypy. Future studies should therefore consider (i) non-excessive licit substance use (e.g., alcohol) in studies investigating the effect of cannabis use on cognition and (ii) both enhanced illicit and licit substance use in studies investigating cognition in schizotypal populations.

Why do convertible issuers simultaneously repurchase stock? An arbitrage-based explanation

We examine why firms combine convertible debt offerings with stock repurchases. In 2006, 33% of the convertible issuers in the US simultaneously repurchased stock. These combined transactions are inconsistent with traditional motivations for convertible issuance. We document that convertible arbitrage drives these stock repurchases. Convertible debt arbitrageurs simultaneously buy convertibles and short sell the issuer’s common stock, resulting in downward pressure on the stock price. To prevent such short-selling activity, firms repurchase their stock directly from arbitrageurs. We show that combined transactions exhibit lower short-selling activity and that convertible arbitrage explains both the size and speed of the stock repurchases.

Fiscal sustainability across government tiers

This paper analyses how fiscal adjustment comes about when both central and sub-national governments are involved in consolidation. We test sustainability of public debt with a fiscal rule for both the federal and regional government. Results for the German Länder show that lower tier governments bear a relatively smaller part of the burden of debt consolidation, if they consolidate at all. Most of the fiscal adjustment occurs via central government debt. In contrast, both the US federal and state levels contribute to consolidation of public finances.

The Global Dimension to Fiscal Sustainability

This paper examines the issue of fiscal sustainability in emerging market countries and industrial countries. We highlight the importance of the time series properties of the primary surplus and debt, and find evidence of a positive long run relationship. Consequently we emphasise, that especially for emerging markets, it is important to recognise the implications of global capital market shocks for fiscal sustainability, a relationship which has hitherto been ignored in the empirical literature. Using a factor model we demonstrate that the relationship between deficit and debt is conditional upon a global factor and we suggest that this global factor is related to world-wide liquidity. We also demonstrate that this acts as a constraint on emerging market economies’ fiscal policy.

Estudio, análisis y mejora de un sistema de gestión de expedientes

El proyecto consistió en el estudio, propuesta y realización de una serie de mejoras derivadas del análisis de un sistema de gestión de expedientes. El sistema analizado es SEDAS, un producto de gestión de los procesos de recobro de deudas desarrollado por Steria. Las mejoras se concentraron en la parametrización y mejora de diversos apartados tales como el modelo de datos, el sistema de generación de informes o la interfaz gráfica.

Electoral Uncertainty and the Deficit Bias in a New Keynesian Economy

Recent attempts to incorporate optimal fiscal policy into New Keynesian models subject to nominal inertia, have tended to assume that policy makers are benevolent and have access to a commitment technology. A separate literature, on the New Political Economy, has focused on real economies where there is strategic use of policy instruments in a world of political conflict. In this paper we combine these literatures and assume that policy is set in a New Keynesian economy by one of two policy makers facing electoral uncertainty (in terms of infrequent elections and an endogenous voting mechanism). The policy makers generally share the social welfare function, but differ in their preferences over fiscal expenditure (in its size and/or composition). Given the environment, policy shall be realistically constrained to be time-consistent. In a sticky-price economy, such heterogeneity gives rise to the possibility of one policy maker utilising (nominal) debt strategically to tie the hands of the other party, and influence the outcome of any future elections. This can give rise to a deficit bias, implying a sub-optimally high level of steady-state debt, and can also imply a sub-optimal response to shocks. The steady-state distortions and inflation bias this generates, combined with the volatility induced by the electoral cycle in a sticky-price environment, can significantly

Three essays on bankruptcy risk

Abstract Market prices of corporate bond spreads and of credit default swap (CDS) rates do not match each other. In this paper, we argue that the liquidity premium, the cheapest-to-deliver (CTD) option and actual market segmentation explain the pricing differences. Using the European transaction data from Reuters and Bloomberg, we estimate the liquidity premium that is time- varying and firm-specific. We show that when time-dependent liquidity premiums are considered, corporate bond spreads and CDS rates behave in a much closer way than previous studies have shown. We find that high equity volatility drives pricing differences that can be explained by the CTD option.

When is Monetary Policy All we Need?

We consider optimal monetary and scal policies in a New Keynesian model of a small open economy with sticky prices and wages. In this benchmark setting monetary policy is all we need - analytical results demonstrate that variations in government spending should play no role in the stabilization of shocks. In extensions we show, rstly, that this is even when true when allowing for in ation inertia through backward-looking rule-of-thumb price and wage-setting, as long as there is no discrepancy between the private and social evaluation of the marginal rate of substitution between consumption and leisure. Secondly, the optimal neutrality of government spending is robust to the issuance of public debt. In the presence of debt government spending will deviate from the optimal steady-state but only to the extent required to cover the deficit, not to provide any additional macroeconomic stabilization. However, unlike government spending variations in tax rates can play a complementary role to monetary policy, as they change relative prices rather than demand.

Pullulation bactérienne de l'intestin grêle [Small intestine bacterial overgrowth]

Small intestine bacterial overgrowth (SIBO) is a condition characterised by nutrient malabsorption and excessive bacteria in the small intestine. It typically presents with diarrhea, flatulence and a syndrome of malabsorption (steatorrhea, macrocytic anemia). However, it may be asymptomatic in the eldery. A high index of suspicion is necessary in order to differentiate SIBO from other similar presenting disorders such as coeliac disease, lactose intolerance or the irritable bowel syndrome. A search for predisposing factor is thus necessary. These factors may be anatomical (stenosis, blind loop), or functional (intestinal hypomotility, achlorydria). The hydrogen breath test is the most frequently used diagnostic test although it lacks standardisation. The treatment of SIBO consists of eliminating predisposing factors and broad-spectrum antibiotic therapy.

The Distributional Consequences of Supply-Side Reforms in General Equilibrium

This paper addresses the issue on whether tax reforms consisten with lower public debt-to-GDP in the long-run can lead to a more efficient and equitable economy. To this end we solve a heterogeneous agent model comprised of a government, a representative capitalist and representative skilled and unskilled workers, under both rational expectations and adaptive learning. Our main ndings are that (i) reductions in capital taxation, while bene cial at the aggregate level, lead to increased inequality mainly due to the substitutability of un- skilled labour and capital; (ii) a fall in taxation for skilled labour is Pareto improving, which is largely explained by its complementarity with the other factor inputs; (iii) all agents would prefer increasing the tax rate on capital to increasing the tax rate on skilled and un- skilled labour since it leads to relatively lower welfare losses; and (iv) heterogeneity in initial beliefs under adaptive learning quantitatively matters for welfare.

Does China overinvest? Evidence from a panel of Chinese firms

This paper addresses the hotly-debated question: do Chinese firms overinvest? A firm-level dataset of 100,000 firms over the period of 2000-07 is employed for this purpose. We initially calculate measures of investment efficiency, which is typically negatively associated with overinvestment. Despite wide disparities across various ownership groups, industries and regions, we find that corporate investment in China has become increasingly efficient over time. However, based on direct measures of overinvestment that we subsequently calculate, we find evidence of overinvestment for all types of firms, even in the most efficient and most profitable private sector. We find that the free cash flow hypothesis provides a good explanation for China‟s overinvestment, especially for the private sector, while in the state sector, overinvestment is attributable to the poor screening and monitoring of enterprises by banks.

Uncertain Fiscal Consolidations

The paper explores the macroeconomic consequences of fiscal consolidations whose timing and composition are uncertain. Drawing on the evidence in Alesina and Ardagna (2010), we emphasize whether or not the fiscal consolidation is driven by tax rises or expenditure cuts. We find that the composition of the fiscal consolidation, its duration, the monetary policy stance, the level of government debt and expectations over the likelihood and composition of fiscal consolidations all matter in determining the extent to which a given consolidation is expansionary and/or successful in stabilizing government debt.

Marriage as a Rat Race: Noisy Pre-Marital Investments with Assortative Matching

We study the incentive to invest to improve marriage prospects, in a frictionless marriage market with non-transferable utility. Stochastic returns to investment eliminate the multiplicity of equilibria in models with deterministic returns, and a unique equilibrium exists under reasonable conditions. Equilibrium investment is efficient when the sexes are symmetric. However, when there is any asymmetry, including an unbalanced sex ratio, investments are generically excessive. For example, if there is an excess of boys, then there is parental over-investment in boys and under-investment in girls, and total investment will be excessive.