Giampaolo Greco

Analysis of risk factors for abdominal aortic aneurysm in a cohort of more than 3 million individuals.

BACKGROUND Abdominal aortic aneurysm (AAA) disease is an insidious condition with an 85% chance of death after rupture. Ultrasound screening can reduce mortality, but its use is advocated only for a limited subset of the population at risk. METHODS We used data from a retrospective cohort of 3.1 million patients who completed a medical and lifestyle questionnaire and were evaluated by ultrasound imaging for the presence of AAA by Life Line Screening in 2003 to 2008. Risk factors associated with AAA were identified using multivariable logistic regression analysis. RESULTS We observed a positive association with increasing years of smoking and cigarettes smoked and a negative association with smoking cessation. Excess weight was associated with increased risk, whereas exercise and consumption of nuts, vegetables, and fruits were associated with reduced risk. Blacks, Hispanics, and Asians had lower risk of AAA than whites and Native Americans. Well-known risk factors were reaffirmed, including male gender, age, family history, and cardiovascular disease. A predictive scoring system was created that identifies aneurysms more efficiently than current criteria and includes women, nonsmokers, and individuals aged <65 years. Using this model on national statistics of risk factors prevalence, we estimated 1.1 million AAAs in the United States, of which 569,000 are among women, nonsmokers, and individuals aged <65 years. CONCLUSIONS Smoking cessation and a healthy lifestyle are associated with lower risk of AAA. We estimated that about half of the patients with AAA disease are not eligible for screening under current guidelines. We have created a high-yield screening algorithm that expands the target population for screening by including at-risk individuals not identified with existing screening criteria.

Managing the Prevention of Retained Surgical Instruments: What Is the Value of Counting?

Objective:Preventing retained foreign bodies is critical for patient safety. However, the value of counting surgical instruments and the reliability of the information provided have never been quantified. This study examines the diagnostic characteristics of counting and its impact on surgical costs. Methods:We examined data from the Medical Event Reporting System-Total HealthSystem (MERS-TH), administrative hospital, and the New York State Cardiac Surgery Report databases (2000–2004). The cost per count discrepancy was examined by studying a cohort of patients undergoing coronary artery bypass graft (CABG) surgery. Linear and logistic multivariable regression models were used for statistical analysis. Results:Of 153,263 operations, there were 1062 count discrepancies. The rate of retained items was 1 of 7000 surgeries or 1 of 70 discrepancy cases. Final count discrepancies identified 77% and prevented 54% of retained items. The sensitivity of counting was 77.2%, specificity was 99.2%, but the positive predictive value was only 1.6%. Count discrepancies increased with surgery duration, late time procedures, and number of nursing teams. Bypass time, intravenous nitroglycerin injections, or myocardial infarction in the previous 24 hours were independent predictors of count discrepancies in CABG surgery. The incremental OR cost for CABG because of a count discrepancy was

National outcomes for the treatment of ruptured abdominal aortic aneurysm: Comparison of open versus endovascular repairs

932. Nationally, this would amount to an additional

Defining high-risk patients for endovascular aneurysm repair

24 million/yr in OR CABG cost. Conclusions:This study, for the first time, quantifies the diagnostic accuracy of counting and defines the parameters against which alternative strategies of prevention should be measured, before being adopted in standard practice.

Superfibronectin, a Multimeric Form of Fibronectin, Increases HIV Infection of Primary CD4+ T Lymphocytes

OBJECTIVES Endovascular repair (EVAR) of ruptured abdominal aortic aneurysms (rAAA) has been shown to acutely decrease procedural mortality compared to open aortic repair (OAR). However, little is known about the effect of choice of procedure; EVAR vs OAR, or the impact of physician and institution volume on long-term survival and outcome. METHODS Patients hospitalized with rAAA who underwent either OAR or EVAR, were derived from the Medicare inpatient dataset (1995-2004) using ICD9 codes. We evaluated long-term survival after OAR and EVAR in the entire fee-for-service Medicare population, and then in patients matched by propensity score to create two similar cohorts for comparison with Kaplan-Meier analysis. Annual surgeon and hospital volumes of EVAR (elective and ruptured), OAR (elective and ruptured), and rAAA (EVAR and OAR) were divided into quintiles to determine if increasing volumes correlate with decreasing mortality. Predictors of survival were determined by Cox modeling. RESULTS A total of 43,033 Medicare beneficiaries had rAAA repair: 41,969 had OAR and 1,064 had EVAR. The proportions of patients with diabetes, hypertension, cardiovascular, cerebrovascular, renal disease, hyperlipidemia, and cancer were statistically higher in the EVAR than in the OAR group, whereas lower extremity vascular disease was higher in the OAR group. The initial evaluation of EVAR vs OAR, prior to propensity matching, showed no statistical advantage in EVAR-survival after 90 days. The survival analysis of patients matched by propensity score showed a benefit of EVAR over OAR that persisted throughout the 4 years of follow-up (P = .0042). Perioperative and long-term survival after rAAA repair correlated with increasing annual surgeon and hospital volume in OAR and EVAR and also with rAAA experience. EVAR repair had a protective effect (HR = 0.857, P = .0061) on long-term survival controlling for comorbidities, demographics, and hospital and surgeon volume. CONCLUSION When EVAR and OAR patients are compared using a reliable statistical technique such as propensity analysis, the perioperative survival advantage of rAAA repaired endovascularly is maintained over the long term. Institutional experience with rAAA is critical for survival after either OAR or EVAR.

Matrix Fibronectin Increases HIV Stability and Infectivity

BACKGROUND Endovascular aneurysm repair (EVAR) is commonly used as a minimally invasive technique for repairing infrarenal aortic aneurysms. There have been recent concerns that a subset of high-risk patients experience unfavorable outcomes with this intervention. To determine whether such a high-risk cohort exists and to identify the characteristics of these patients, we analyzed the outcomes of Medicare patients treated with EVAR from 2000-2006. METHODS We identified 66,943 patients who underwent EVAR from Inpatient Medicare database. The overall 30-day mortality was 1.6%. A risk model for perioperative mortality was developed by randomly selecting 44,630 patients; the other one third of the dataset was used to validate the model. The model was deemed reliable (Hosmer-Lemeshow statistics were P = .25 for the development, P = .24 for the validation model) and accurate (c = 0.735 and c = 0.731 for the development and the validation model, respectively). RESULTS In our scoring system, where scores ranged between 1 and 7, the following were identified as significant baseline factors that predict mortality: renal failure with dialysis (score = 7); renal failure without dialysis (score = 3); clinically significant lower extremity ischemia (score = 5); patient age >or=85 years (score = 3), 75-84 years (score = 2), 70-74 years (score = 1); heart failure (score = 3); chronic liver disease (score = 3); female gender (score = 2); neurological disorders (score = 2); chronic pulmonary disease (score = 2); surgeon experience in EVAR <3 procedures (score = 1); and hospital annual volume in EVAR <7 procedures (score = 1). The majority of Medicare patients who were treated (96.6%, n = 64,651) had a score of 9 or less, which correlated with a mortality <5%. Only 3.4% of patients had a mortality >or=5% and 0.8% of patients (n = 509) had a score of 13 or higher, which correlated with a mortality >10%. CONCLUSION We conclude that there is a high-risk cohort of patients that should not be treated with EVAR because of prohibitively high mortality; however, this cohort is small. Our scoring system, which is based on patient and institutional factors, provides criteria that can be easily used by clinicians to quantify perioperative risk for EVAR candidates.

Diabetes and the Association of Postoperative Hyperglycemia With Clinical and Economic Outcomes in Cardiac Surgery

The ability of viruses and bacteria to interact with the extracellular matrix plays an important role in their infectivity and pathogenicity. Fibronectin is a major component of the extracellular matrix in lymph node tissue, the main site of HIV deposition and replication during the chronic phase of infection. Therefore, we asked whether matrix fibronectin (FN) could affect the ability of HIV to infect lymphocytes. To study the role of matrix FN on HIV infection, we used superfibronectin (sFN), a multimeric form of FN that closely resembles in vivo matrix FN. In this study we show that HIV-1IIIB efficiently binds to multimeric fibronectin (sFN) and that HIV infection of primary CD4+ lymphocytes is enhanced by >1 order of magnitude in the presence of sFN. This increase appears to be due to increased adhesion of viral particles to the cell surface in the presence of sFN, followed by internalization of virus. Enzymatic removal of cell surface proteoglycans inhibited the adhesion of HIV-1IIIB/sFN complexes to lymphocytes. In contrast, Abs to integrins had no effect on binding of HIV-1IIIB/sFN complexes to lymphocytes. The III1-C peptide alone also bound HIV-1IIIB efficiently and enhanced HIV infection, although not as effectively as sFN. HIV-1IIIB gp120 envelope protein binds to the III1-C region of sFN and may be important in the interaction of virus with matrix FN. We conclude that HIV-1IIIB specifically interacts with the III1-C region within matrix FN, and that this interaction may play a role in facilitating HIV infection in vivo, particularly in lymph node tissue.

Development of a novel scoring tool for the identification of large ≥5 cm abdominal aortic aneurysms.

HIV particles are detected extracellularly in lymphoid tissues, a major reservoir of the virus. We previously reported that a polymerized form of fibronectin (FN), superfibronectin (sFN), as well as a fragment of FN, III1-C, enhanced infection of primary CD4+ T cells by HIV-1IIIB. We now show that sFN enhances infection of primary CD4+ T cells by both R5 and X4 strains of HIV-1. Using HIV pseudotyped with different envelope glycoproteins (gp120) and HOS cells transfected with various chemokine receptors alone or in combination with the CD4 molecule, we show that sFN-mediated enhancement requires the CD4 receptor and does not alter the specificity of gp120 for different chemokine receptors. Because the III1-C fragment also resulted in enhancement, we asked whether proteolysis of FN generated fragments capable of enhancing HIV infection. We found that progressive proteolysis of FN by chymotrypsin correlates with an enhancement of HIV infection in both primary CD4+ T cells and the IG5 reporter cell line. Furthermore, incubation of HIV with sFN significantly prolonged infectivity at 37°C compared with dimeric FN or BSA. In conclusion, these results indicate that polymerized (matrix) or degraded (inflammation-associated), but not dimeric (plasma), FN are capable of enhancing infection by HIV-1, independent of the coreceptor specificity of the strains. Moreover, virions bound to matrix FN maintain infectivity for longer periods of time than do virions in suspension. This study suggests that matrix proteins and their conformational status may play a role in the pathogenesis of HIV.

Patient-directed Internet-based Medical Image Exchange:

OBJECTIVE The management of postoperative hyperglycemia is controversial and generally does not take into account pre-existing diabetes. We analyzed clinical and economic outcomes associated with postoperative hyperglycemia in cardiac surgery patients, stratifying by diabetes status. RESEARCH DESIGN AND METHODS Multicenter cohort study in 4,316 cardiac surgery patients operated on in 2010. Glucose was measured at 6-h intervals for 48 h postoperatively. Outcomes included cost, hospital length of stay (LOS), cardiac and respiratory complications, major infections, and death. Associations between maximum glucose levels and outcomes were assessed with multivariable regression and recycled prediction analyses. RESULTS In patients without diabetes, increasing glucose levels were associated with a gradual worsening of outcomes. In these patients, hyperglycemia (≥180 mg/dL) was associated with an additional cost of

A Prospective Multi-Institutional Cohort Study of Mediastinal Infections After Cardiac Operations

3,192 (95% CI 1,972 to 4,456), an additional hospital LOS of 0.8 days (0.4 to 1.3), an increase in infections of 1.6% (0.5 to 2.8), and an increase in respiratory complications of 2.6% (0.0 to 5.3). However, among patients with insulin-treated diabetes, optimal outcomes were associated with glucose levels considered to be hyperglycemic (180 to 240 mg/dL). This level of hyperglycemia was associated with cost reductions of