Long-term mortality prediction after operations for type A ascending aortic dissection

<p>Abstract</p> <p>Background</p> <p>There are few long-term mortality prediction studies after acute aortic dissection (AAD) Type A and none were performed using new models such as neural networks (NN) or support vector machines (SVM) which may show a higher discriminatory potency than standard multivariable models.</p> <p>Methods</p> <p>We used 32 risk factors identified by Literature search and previously assessed in short-term outcome investigations. Models were trained (50%) and validated (50%) on 2 random samples from a consecutive 235-patient cohort. NN were run only on patients with complete data for all included variables (N = 211); SVM on the overall group. Discrimination was assessed by receiver operating characteristic area under the curve (AUC) and Gini's coefficients along with classification performance.</p> <p>Results</p> <p>There were 84 deaths (36%) occurring at 564 ± 48 days (95%CI from 470 to 658 days). Patients with complete variables had a slightly lower death rate (60 of 211, 28%). NN classified 44 of 60 (73%) dead patients and 147 of 151 (97%) long-term survivors using 5 covariates: immediate post-operative chronic renal failure, circulatory arrest time, the type of surgery on ascending aorta plus hemi-arch, extracorporeal circulation time and the presence of Marfan habitus. Global accuracies of training and validation NN were excellent with AUC respectively 0.871 and 0.870 but classification errors were high among patients who died. Training SVM, using a larger number of covariates, showed no false negative or false positive cases among 118 randomly selected patients (error = 0%, AUC 1.0) whereas validation SVM, among 117 patients, provided 5 false negative and 11 false positive cases (error = 22%, AUC 0.821, p < 0.01 versus NN results). An html file was produced to adopt and manipulate the selected parameters for practical predictive purposes.</p> <p>Conclusions</p> <p>Both NN and SVM accurately selected a few operative and immediate post-operative factors and the Marfan habitus as long-term mortality predictors in AAD Type A. Although these factors were not new per se, their combination may be used in practice to index death risk post-operatively with good accuracy.</p

Quality of life and treatment satisfaction in adults with Type 1 diabetes: A comparison between continuous subcutaneous insulin infusion and multiple daily injections

Aims: The aim of this case-control study was to compare quality of life (QoL) and treatment satisfaction in adults with Type 1 diabetes (T1DM) treated with either continuous subcutaneous insulin infusion (CSII) or multiple daily injections (MDI). Methods: Consecutive patients aged between 18 and 55 years, and attending diabetes clinics for a routine visit, completed the Diabetes-Specific Quality-of-Life Scale (DSQOLS), the Diabetes Treatment Satisfaction Questionnaire (DTSQ) and the SF-36 Health Survey (SF-36). Case (CSII) and control subjects (MDI) were recruited in a 1 : 2 ratio. Results: Overall, 1341 individuals were enrolled by 62 diabetes clinics; 481 were cases and 860 control subjects. Cases had a longer diabetes duration and were more likely to have eye and renal complications. Age, school education, occupation and HbA1c were similar. Of control subjects, 90% followed glargine-based MDI regimens and 10% used NPH-based MDI regimens. On multivariate analysis, after adjusting for socioeconomic and clinical characteristics, scores in the following areas of the DSQOLS were higher in cases than control subjects: diet restrictions (β = 5.96; P &lt; 0.0001), daily hassles (β = 3.57; P = 0.01) and fears about hypoglycaemia (β = 3.88; P = 0.006). Treatment with CSII was also associated with a markedly higher DTSQ score (β = 4.13; P &lt; 0.0001) compared with MDI. Results were similar when CSII was compared separately with glargine- or NPH-based MDI regimens. Conclusions: This large, non-randomized, case-control study suggests quality of life gains deriving from greater lifestyle flexibility, less fear of hypoglycaemia, and higher treatment satisfaction, when CSII is compared with either glargine-based or NPH-based MDI regimens. © 2008 The Authors

Association of kidney disease measures with risk of renal function worsening in patients with type 1 diabetes

Background: Albuminuria has been classically considered a marker of kidney damage progression in diabetic patients and it is routinely assessed to monitor kidney function. However, the role of a mild GFR reduction on the development of stage 653 CKD has been less explored in type 1 diabetes mellitus (T1DM) patients. Aim of the present study was to evaluate the prognostic role of kidney disease measures, namely albuminuria and reduced GFR, on the development of stage 653 CKD in a large cohort of patients affected by T1DM. Methods: A total of 4284 patients affected by T1DM followed-up at 76 diabetes centers participating to the Italian Association of Clinical Diabetologists (Associazione Medici Diabetologi, AMD) initiative constitutes the study population. Urinary albumin excretion (ACR) and estimated GFR (eGFR) were retrieved and analyzed. The incidence of stage 653 CKD (eGFR &lt; 60 mL/min/1.73 m2) or eGFR reduction &gt; 30% from baseline was evaluated. Results: The mean estimated GFR was 98 \ub1 17 mL/min/1.73m2 and the proportion of patients with albuminuria was 15.3% (n = 654) at baseline. About 8% (n = 337) of patients developed one of the two renal endpoints during the 4-year follow-up period. Age, albuminuria (micro or macro) and baseline eGFR &lt; 90 ml/min/m2 were independent risk factors for stage 653 CKD and renal function worsening. When compared to patients with eGFR &gt; 90 ml/min/1.73m2 and normoalbuminuria, those with albuminuria at baseline had a 1.69 greater risk of reaching stage 3 CKD, while patients with mild eGFR reduction (i.e. eGFR between 90 and 60 mL/min/1.73 m2) show a 3.81 greater risk that rose to 8.24 for those patients with albuminuria and mild eGFR reduction at baseline. Conclusions: Albuminuria and eGFR reduction represent independent risk factors for incident stage 653 CKD in T1DM patients. The simultaneous occurrence of reduced eGFR and albuminuria have a synergistic effect on renal function worsening

Schedule-based dynamic assignment models for air transport networks

This paper presents a class of dynamic assignment models specified through a schedule-based approach that can be used to compute flows on air transport networks. They can be considered an extension to air transport of the schedule-based approach specified by the author for transit networks (Nuzzolo et al. 2003). This assignment model has been applied to the Italian national air transport network in order to verify the specification and implementation of the proposed approach

Schedule-based dynamic assignment models for air transport networks

This paper presents a class of dynamic assignment models specified through a schedule-based approach that can be used to compute flows on air transport networks. They can be considered an extension to air transport of the schedule-based approach specified by the author for transit networks (Nuzzolo et al. 2003). This assignment model has been applied to the Italian national air transport network in order to verify the specification and implementation of the proposed approach

Distribuzione urbana delle merci tramite ferrovia regionale: un’applicazione test nella penisola Sorrentina

In questa nota è affrontato il problema della distribuzione delle merci utilizzando per l’accesso all’area metropolitana le presenti infrastrutture ferroviarie. È descritta una metodologia per l’analisi della fattibilità tecnico-economica del sistema di progetto che prevede la messa a punto di un sistema di modelli per la stima della domanda merci di prodotti finali; è sinteticamente descritta l’applicazione alla penisola Sorrentina

Distribuzione urbana delle merci tramite ferrovia regionale: un’applicazione test nella penisola Sorrentina

In questa nota è affrontato il problema della distribuzione delle merci utilizzando per l’accesso all’area metropolitana le presenti infrastrutture ferroviarie. È descritta una metodologia per l’analisi della fattibilità tecnico-economica del sistema di progetto che prevede la messa a punto di un sistema di modelli per la stima della domanda merci di prodotti finali; è sinteticamente descritta l’applicazione alla penisola Sorrentina

Logistica e territorio: metodi e strumenti per la progettazione delle reti di trasporto merci

La logistica territoriale si può definire come la disciplina che si occupa delle metodologie e degli strumenti di supporto alle amministrazioni pubbliche ai diversi livelli (nazionale, regionale ed urbano/metropolitano) per la pianificazione, la progettazione e la gestione delle reti di infrastrutture e servizi di trasporto nell’ambito dei piani settoriali per il trasporto merci e la logistica, dove per progettazione si intende la localizzazione ed il dimensionamento dei nodi di trasporto e delle relative connessioni. La logistica territoriale viene concepita come punto di incontro pubblico (enti locali) e privato (imprenditori, operatori di logistica, ecc.), con l’obiettivo di massimizzare i benefici economici della collettività, nel rispetto dei vincoli esistenti, tra cui quelli ambientali. Nel seguente lavoro vengono sintetizzati ed analizzati gli approcci, i metodi e gli strumenti della logistica territoriale di supporto per la pianificazione e la programmazione di interventi sul sistema di trasporto a supporto della mobilità delle cose