Maximum Agreement Linear Prediction via the Concordance Correlation Coefficient

This paper examines distributional properties and predictive performance of the estimated maximum agreement linear predictor (MALP) introduced in Bottai, Kim, Lieberman, Luta, and Pena (2022) paper in The American Statistician, which is the linear predictor maximizing Lin's concordance correlation coefficient (CCC) between the predictor and the predictand. It is compared and contrasted, theoretically and through computer experiments, with the estimated least-squares linear predictor (LSLP). Finite-sample and asymptotic properties are obtained, and confidence intervals are also presented. The predictors are illustrated using two real data sets: an eye data set and a bodyfat data set. The results indicate that the estimated MALP is a viable alternative to the estimated LSLP if one desires a predictor whose predicted values possess higher agreement with the predictand values, as measured by the CCC

Routine use of completion imaging after infrainguinal bypass is not associated with higher bypass graft patency

BackgroundSignificant variability exists in completion imaging (CIM) after infrainguinal lower extremity bypass (LEB). We evaluated the use of CIM and compared graft patency in patients treated by surgeons who performed routine CIM vs those who performed selective CIM.MethodsWe reviewed the Vascular Study Group of New England database (2003-2010) and assessed the use of CIM (angiography or duplex ultrasound) among patients undergoing LEB. The surgeon-specific CIM strategy was categorized as routine (≥80% of LEBs) vs selective (<80% of LEBs). Exclusion criteria included acute limb ischemia, bilateral procedures, and surgeon volume <10 cases per study period. Primary graft patency at discharge and at 1 year was analyzed on the basis of CIM use and surgeon-specific CIM strategy. Multivariable analyses were performed using Poisson regression.ResultsAmong 2032 LEB procedures performed by 48 surgeons, CIM was used in 1368 cases (67.3%). CIM was performed in 72% of autogenous LEBs and 52% of prosthetic grafts. Dialysis (odds ratio [OR], 1.7; 95% confidence interval [CI], 1.1-2.6; P = .01), elective LEB (OR, 2.6; 95% CI, 1.4-4.8; P = .002), great saphenous vein conduit (OR, 2.0; 95% CI, 1.6-2.5; P < .001), and tibial or pedal target artery (OR, 1.8; 95% CI, 1.4-2.3; P < .001) were associated with CIM use. In multivariate models, CIM was not associated with improved primary graft patency at discharge (OR, 1.1; 95% CI, 0.7-1.7; P = .64) or at 1 year (OR, 0.9; 95% CI, 0.7-1.2; P = .47). Sixteen surgeons (33%) were routine users and 32 (67%) were selective users of CIM. Among patients of routine vs selective CIM users, primary graft patency at discharge and at 1 year was 96% vs 94% (P = .21) and 68% vs 72% (P = .09), respectively. In multivariate analysis, routine or selective CIM strategy was not associated with improved discharge (rate ratio, 0.8; 95% CI, 0.6-1.1; P = .31) or 1-year (rate ratio, 1.1; 95% CI, 0.9-1.2; P = .56) graft patency.ConclusionsIn our observational cohort, CIM does not improve short-term and 1-year bypass graft patency in infrainguinal LEB. The surgeon-specific strategy of selective CIM after LEB has outcomes comparable to those of routine CIM

Progressive Improvement of T

Testosterone deficiency leads to bone loss and testosterone treatment has a beneficial effect. This study investigated the effects of normalizing serum testosterone on bone mineral density in 45 men with osteoporosis, diagnosed with testosterone deficiency (serum testosterone levels <12.1 nmol/L, T-scores: (mean ± SD) −3.12 ± 0.45, minimum: −4.10, and maximum: −2.60). In a cumulative, prospective, registry study of hypogonadal men (mean age: 53 ± 7 years) they received parenteral testosterone undecanoate of 1000 mg/12 weeks for up to six years. After one year 44 men were included in the registry, after two years 36 men, after three years 32 men, after four years 25 men, after five years 10 men and after six years 4 men. The declining numbers do not reflect drop-out rates but are a result of the registry design. Over the 6 year period there was a significant and progressive improvement of the T-scores in these men. Normalizing of serum testosterone leads to an improvement of bone mineral density and this improvement was progressive with the time period of testosterone administration. In this study of 6-years many men with testosterone deficiency suffered from classical diagnoses (Klinefelter’s syndrome and testicular pathology) hitherto undiagnosed

Outpatient prescription practices in patients with atrial fibrillation (from the NCDR PINNACLE registry)

This study sought to evaluate inappropriate prescribing practices in an atrial fibrillation (AF) population, as outlined by the 2016 ACC/AHA Clinical Performance and Quality Measures for Adults with Atrial Fibrillation or Atrial Flutter document. The 2016 AF quality measures document specified medications to avoid in certain AF populations, including aspirin and anticoagulant combination therapy in patients without cardiovascular disease, and non-dihydropyridine calcium channel blockers in patients with reduced ejection fraction. Using data from the NCDR PINNACLE registry, a national outpatient cardiology practice registry, we assessed rates of inappropriate prescription of two types of medications among AF outpatients from 5/1/2008-5/1/2016. Overall rates of inappropriate prescription and variation by practice were calculated. Patient and practice factors associated with inappropriate prescription were assessed in adjusted analyses. A total of 107,759 of 658,250 (16.4%) patients without cardiovascular disease were inappropriately prescribed an antiplatelet and anticoagulant together, and 5,731 of 150,079 (3.8%) patients with reduced ejection fraction were inappropriately prescribed a non-dihydropyridine calcium channel blocker. Overall, 14.8% of AF patients were prescribed medications that were not recommended. Both patient and practice factors were associated with inappropriate prescribing, and the adjusted practice-level median odds ratio for inappropriate prescription was 1.70 (95% CI: 1.61-1.82), indicating a 70% likelihood that 2 random practices would treat identical AF patients differently. In a large registry of AF patients treated in cardiology practices, overall rates of inappropriate prescription practices, as defined by the 2016 AF quality measures, were relatively low, but significant practice variation was present

Mortality Not Correlated With Paclitaxel Exposure

n/

N-Terminal Pro–B-Type Natriuretic Peptide in the Emergency Department: The ICON-RELOADED Study

Background Contemporary reconsideration of diagnostic N-terminal pro–B-type natriuretic peptide (NT-proBNP) cutoffs for diagnosis of heart failure (HF) is needed. Objectives This study sought to evaluate the diagnostic performance of NT-proBNP for acute HF in patients with dyspnea in the emergency department (ED) setting. Methods Dyspneic patients presenting to 19 EDs in North America were enrolled and had blood drawn for subsequent NT-proBNP measurement. Primary endpoints were positive predictive values of age-stratified cutoffs (450, 900, and 1,800 pg/ml) for diagnosis of acute HF and negative predictive value of the rule-out cutoff to exclude acute HF. Secondary endpoints included sensitivity, specificity, and positive (+) and negative (−) likelihood ratios (LRs) for acute HF. Results Of 1,461 subjects, 277 (19%) were adjudicated as having acute HF. The area under the receiver-operating characteristic curve for diagnosis of acute HF was 0.91 (95% confidence interval [CI]: 0.90 to 0.93; p < 0.001). Sensitivity for age stratified cutoffs of 450, 900, and 1,800 pg/ml was 85.7%, 79.3%, and 75.9%, respectively; specificity was 93.9%, 84.0%, and 75.0%, respectively. Positive predictive values were 53.6%, 58.4%, and 62.0%, respectively. Overall LR+ across age-dependent cutoffs was 5.99 (95% CI: 5.05 to 6.93); individual LR+ for age-dependent cutoffs was 14.08, 4.95, and 3.03, respectively. The sensitivity and negative predictive value for the rule-out cutoff of 300 pg/ml were 93.9% and 98.0%, respectively; LR− was 0.09 (95% CI: 0.05 to 0.13). Conclusions In acutely dyspneic patients seen in the ED setting, age-stratified NT-proBNP cutpoints may aid in the diagnosis of acute HF. An NT-proBNP <300 pg/ml strongly excludes the presence of acute HF

Rationale and Design of the ICON-RELOADED Study: International Collaborative of Nterminal pro-B-type Natriuretic Peptide Re-evaluation of Acute Diagnostic Cut-Offs in the Emergency Department

Objectives The objectives were to reassess use of amino-terminal pro B-type natriuretic peptide (NT-proBNP) concentrations for diagnosis and prognosis of acute heart failure (HF) in patients with acute dyspnea. Background NT-proBNP facilitates diagnosis, prognosis, and treatment in patients with suspected or proven acute HF. As demographics of such patients are changing, previous diagnostic NT-proBNP thresholds may need updating. Additionally, value of in-hospital NT-proBNP prognostic monitoring for HF is less understood. Methods In a prospective, multicenter study in the United States and Canada, patients presenting to emergency departments with acute dyspnea were enrolled, with demographic, medication, imaging, and clinical course information collected. NT-proBNP analysis will be performed using the Roche Diagnostics Elecsys proBNPII immunoassay in blood samples obtained at baseline and at discharge (if hospitalized). Primary end points include positive predictive value of previously established age-stratified NT-proBNP thresholds for the adjudicated diagnosis of acute HF and its negative predictive value to exclude acute HF. Secondary end points include sensitivity, specificity, and positive and negative likelihood ratios for acute HF and, among those with HF, the prognostic value of baseline and predischarge NT-proBNP for adjudicated clinical end points (including all-cause death and hospitalization) at 30 and 180 days. Results A total of 1,461 dyspneic subjects have been enrolled and are eligible for analysis. Follow-up for clinical outcome is ongoing. Conclusions The International Collaborative of N-terminal pro–B-type Natriuretic Peptide Re-evaluation of Acute Diagnostic Cut-Offs in the Emergency Department study offers a contemporary opportunity to understand best diagnostic cutoff points for NT-proBNP in acute HF and validate in-hospital monitoring of HF using NT-proBNP

Outcomes of renal transplantation in patients with AL amyloidosis: an international collaboration through The International Kidney and Monoclonal Gammopathy Research Group

Effective systemic therapies suppress toxic light chain production leading to an increased proportion of patients with light chain (AL) amyloidosis who survive longer albeit with end-stage renal disease. There is a critical need to identify patients in this population who benefit from renal transplantation. This multicenter, observational study from five countries includes 237 patients with AL amyloidosis who underwent renal transplantation between 1987 and 2020. With a median follow-up of 8.5 years, the median overall survival from renal transplantation was 8.6 years and was significantly longer in patients with complete and very good partial hematologic responses (CR + VGPR) compared to less than VGPR (9 versus 6.8 years; HR: 1.5, P = 0.04 [95% CI: 1–2.1]) at renal transplantation. Median graft survival was 7.8 years and was better in the CR + VGPR group (8.3 vs 5.7 years, HR: 1.4, P = 0.05 [95% CI: 1–2]). The frequency and time to amyloid recurrence in the graft was also lower (16% vs 37%, p = 0.01) and longer (median time not achieved vs 10 years, p = 0.001) in the CR + VGPR group. Comparing CR vs. VGPR there was no difference in overall or graft survival. Although 69 patients (29%) experienced hematologic relapse, treatment effectively prevented graft loss in the majority (87%). Renal transplantation in selected AL amyloidosis patients is associated with extended overall and renal graft survival. Patients with hematologic CR or VGPR have the most favorable outcomes, and these patients should be considered for renal transplantation

Predicting future left anterior descending artery events from non-culprit lesions:insights from the Lipid-Rich Plaque study

AIMS: The left anterior descending (LAD) artery is the most frequently affected site by coronary artery disease. The prospective Lipid Rich Plaque (LRP) study, which enrolled patients undergoing imaging of non-culprits followed over 2 years, reported the successful identification of coronary segments at risk of future events based on near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS) lipid signals. We aimed to characterize the plaque events involving the LAD vs. non-LAD segments. METHODS AND RESULTS: LRP enrolled 1563 patients from 2014 to 2016. All adjudicated plaque events defined by the composite of cardiac death, cardiac arrest, non-fatal myocardial infarction, acute coronary syndrome, revascularization by coronary bypass or percutaneous coronary intervention, and rehospitalization for angina with >20% stenosis progression and reported as non-culprit lesion-related major adverse cardiac events (NC-MACE) were classified by NIRS-IVUS maxLCBI4 mm (maximum 4-mm Lipid Core Burden Index) ≤400 or >400 and association with high-risk-plaque characteristics, plaque burden ≥70%, and minimum lumen area (MLA) ≤4 mm2. Fifty-seven events were recorded with more lipid-rich plaques in the LAD vs. left circumflex and right coronary artery; 12.5% vs. 10.4% vs. 11.3%, P = 0.097. Unequivocally, a maxLCBI4 mm >400 in the LAD was more predictive of NC-MACE [hazard ratio (HR) 4.32, 95% confidence interval (CI) (1.93-9.69); P = 0.0004] vs. [HR 2.56, 95% CI (1.06-6.17); P = 0.0354] in non-LAD segments. MLA ≤4 mm2 within the maxLCBI4 mm was significantly higher in the LAD (34.1% vs. 25.9% vs. 13.7%, P < 0.001). CONCLUSION: Non-culprit lipid-rich segments in the LAD were more frequently associated with plaque-level events. LAD NIRS-IVUS screening may help identify patients requiring intensive surveillance and medical treatment