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Rigorous and reproducible methodology of controlling for bias is essential for high-quality, evidence-based studies. Propensity score matching (PSM) is a valuable way to control for bias and achieve pseudo-randomization in retrospective observation studies. The purpose of this review is to 1) provide a clear conceptual framework for PSM, 2) recommend how to best report its use in studies, and 3) offer some practical examples of implementation. First, this article covers the concepts behind PSM, discusses its pros and cons, and compares it with other methods of controlling for bias, namely, hard/exact matching and regression analysis. Second, recommendations are given for what to report in a manuscript when PSM is used. Finally, a worked example is provided, which can also serve as a template for the reader's own studies. A study's conclusions are only as strong as its methods. PSM is an invaluable tool for producing rigorous and reproducible results in observational studies. The goal of this article is to give practicing clinical physicians not only a better understanding of PSM and its implications but the ability to implement it for their own studies. STUDY DESIGN: Review. [ABSTRACT FROM AUTHOR]

Background: Current guidelines recommend measuring natriuretic peptide biomarkers to establish prognosis in patients with chronic heart failure with reduced ejection fraction (HFrEF). We assessed whether a combination biomarkers approach improve prognostication in patients with stable HFrEF.Methods and Results: An observational cohort study recruited 202 patients with stable HFrEF at a single center, tertiary care hospital undergoing elective cardiac resynchronization therapy device placement from 2013 to 2015. Twenty-four biomarkers were analyzed individually and in combination using Cox proportion hazard regression model for major adverse cardiac events (ie, death, cardiac transplant, left ventricular assist device placement), and major adverse cardiac events plus HF hospitalizations. The single best biomarker for predicting major adverse cardiac events is peripheral mid-regional pro-adrenomedullin (C statistic = 0.771 ± 0.045) compared to current guideline recommended N-terminal pro b-type natriuretic peptide (C=0.668 ± 0.046). The best combined biomarkers for predicting major adverse cardiac events are blood urea nitrogen, coronary sinus C-reactive protein, peripheral mid-regional pro-atrial natriuretic peptide and peripheral soluble IL-1 receptor-like 1 (C = 0.767 ± 0.036).Conclusions: In this observational cohort, the combined biomarkers (blood urea nitrogen, C-reactive protein, mid-regional pro-atrial natriuretic peptide and soluble IL-1 receptor-like 1) or the single biomarker (mid-regional pro-adrenomedullin) was superior to N-terminal pro B-type natriuretic peptide, the current guideline recommended biomarker in predicting cardiovascular outcomes in patients with HFrEF. Larger studies are needed to validate these findings and examine whether single or combined biomarkers improve HFrEF prognostication. [ABSTRACT FROM AUTHOR]

Background: Cardiac sympathetic denervation (CSD) is a promising treatment for patients with structural heart disease (SHD) and refractory ventricular tachyarrhythmias (VTs). The effect of CSD on atrial rhythm as well as the prognostic impact of atrial arrhythmias (AAs) or left atrial volume index (LAVI) on CSD outcome are unknown.Objectives: The goals of this study were to evaluate the impact of AAs and LAVI on CSD outcome and to assess changes in AAs burden and in atrial pacing after CSD.Methods: Patients with SHD undergoing CSD for VTs were analyzed. Hazards models were built to assess predictors of sustained VT/implantable cardioverter-defibrillator (ICD) shock recurrences and death/orthotopic heart transplant (OHT). Changes before vs after CSD were assessed using ICD, clinical, and echocardiographic data. A drug index was devised to correct for medication use.Results: Between 2009 and 2018, 91 patients (mean age 56 ± 13 years; mean left ventricular ejection fraction 34% ± 14%; 47% with a history of AAs) underwent left CSD (16%) or bilateral CSD (BCSD). The median follow-up was 14 months (interquartile range 4-37 months). Using multivariable analysis, neither LAVI nor AAs were associated with recurrences; LAVI was an independent predictor of death/OHT. AAs burden did not change after BCSD, but atrial pacing increased from a median of 28% to 72% (P < .01). Left ventricular end-diastolic diameter slightly increased; however, sustained VT/ICD shocks were reduced.Conclusion: In patients with SHD undergoing CSD, LAVI predicts death/OHT. AAs burden, already low at baseline, was unchanged after BCSD, while the need for atrial pacing increased, suggesting an impact of BCSD on sinus node chronotropism. [ABSTRACT FROM AUTHOR]

Geriatric patients require specialized perioperative care, yet the impact of geriatric surgery proportion (a measure of experience) and geriatric surgery volume, on clinical outcomes is unknown. This study analyzes the association between proportion and volume and clinical outcomes after high-risk geriatric surgery. Using the 2014 National Inpatient Sample, hospital encounters for older adults (≥65 years) undergoing high-risk geriatric surgery were identified. Geriatric surgery volume was defined as a hospital's annual volume of geriatric patients undergoing high-risk geriatric surgery. Geriatric surgery proportion was calculated as volume divided by the sum of high-risk surgeries in all ages. Hierarchical multivariable regression models identified predictors of inpatient mortality, postoperative length of stay, and discharge to nursing facility. There were an estimated 514,950 hospital encounters for older adults undergoing high-risk geriatric surgery from 3,115 hospitals. Mean proportion was 0.53 ± 0.19; median volume was 60 cases per year, ranging from 5 to 3,235. After adjustment, comparing the 90th to 10th percentiles, higher proportion was associated with decreased mortality (odds ratio [95% confidence interval] 0.81 [0.73–0.88]; P <.001) and shorter postoperative length of stay (–4.44% (–5.49 to −3.39%); P <.0001). Higher volume was not associated with mortality but was associated with longer length of stay (7.76% [6.75–8.77%]; P <.0001) and decreased discharge to nursing facility (0.87 [0.79–0.95]; P=. 003). Treatment of geriatric patients at hospitals with the highest proportion of high-risk geriatric surgery, or the most experience, is associated with improved outcomes. High-proportion hospitals should be examined to understand the mechanisms by which better quality geriatric surgical care is achieved, while lower-proportion hospitals may be targets for quality improvement efforts. [ABSTRACT FROM AUTHOR]

Background: In acute stroke randomized trials, missingness of final functional outcome data reduces study power and potentially biases findings of treatment effect. Best methods for handling missing outcome data have not been well delineated for diseases with monophasic onset and subsequent improvement, like acute stroke.Methods: We simulated data missingness in the public dataset of the landmark, second NINDS-tPA trial, by randomly removing 5%-25% of actual values for the 3-month modified Rankin Scale (mRS) of global disability. We evaluated 5 missing data-handling methods: complete case analysis (CCA), worst case imputation (WCI), last observation carried forward (LOCF), multiple imputation using baseline covariates only (MI-B), and multiple imputation using baseline and postbaseline observations (MI-BP).Results: With the original trial's 333 patients, tissue plasminogen activator was associated with 3-month disability benefit, both for mRS dichotomized at 0-1 (P = .014) and shift analysis (P = .035). Distance (root mean square error) of imputed from actual mRS values was best for LOCF (1.17) and MI-BP (1.28), intermediate for MI-B (1.89) and worst for WCI (3.77). Directional bias (mean difference) was least for MI-BP (.01) and MI-B (-.16), intermediate for LOCF (-.37), and worst for WCI (-3.22). Preservation of formally positive results was greatest for MI-BP and LOCF (preserved at all missingness rates), intermediate for CCA and MI-B (preserved only with missingness <10%-20%), and least for WCI (preserved only with missingness <5%-20%).Conclusions: For acute stroke trials, multiple imputation using baseline and postbaseline observations is an advantageous approach to missing outcome data-handling, yielding high accuracy, reduced directional bias, and greater preservation of study power. [ABSTRACT FROM AUTHOR]

The MRI-AST (MAST) score accurately identifies patients with at-risk nonalcoholic steatohepatitis, defined as nonalcoholic steatohepatitis with nonalcoholic fatty liver disease activity score ≥4 and fibrosis stage ≥2 at highest risk for disease progression. It is important to determine the robustness of the MAST score in predicting major adverse liver outcomes (MALO), hepatocellular carcinoma (HCC), liver transplant, and death. This retrospective analysis included patients with nonalcoholic fatty liver disease from a tertiary care center who underwent magnetic resonance imaging proton density fat fraction, magnetic resonance elastography, and laboratory testing within 6 months from 2013 to 2022. Other causes of chronic liver disease were excluded. Hazard ratios between logit MAST and MALO (ascites, hepatic encephalopathy, or bleeding esophageal varices), liver transplant, HCC, or liver-related death were computed using a Cox proportional hazards regression model. We computed the hazard ratio of MALO or death associated with MAST scores 0.165–0.242 and 0.242–1.000, using MAST scores 0.000–0.165 as the reference group. Among 346 total patients, average age was 58.8 years with 52.9% females and 34.4% with type 2 diabetes. Average alanine aminotransferase was 50.7 IU/L (24.3–60.0 IU/L), aspartate aminotransferase was 38.05 IU/L (22.00–41.00 IU/L), platelets were 242.9 × 109/L (193.8–290.0 × 109/L), proton density fat fraction was 12.90% (5.90%–18.22%), and liver stiffness on magnetic resonance elastography was 2.75 kPa (2.07–2.90 kPa). Median follow-up was 29.5 months. Fourteen had adverse outcomes, including 10 MALO, 1 HCC, 1 liver transplant, and 2 liver-related deaths. The Cox regression of MAST versus adverse event rate had a hazard ratio of 2.01 (95% confidence interval, 1.59–2.54; P <.0001) for each 1 logit unit increases in MAST. The corresponding Harrell concordance statistic (C statistic) was 0.919 (95% confidence interval, 0.865–0.953). The MAST score ranges of 0.165–0.242 and 0.242–1.0, respectively, had adverse event rate hazard ratio of 7.75 (1.40–42.9; P =.0189) and 22.11 (6.59–74.2; P <.0000) relative to MAST 0–0.165. The MAST score noninvasively identifies at-risk nonalcoholic steatohepatitis and accurately predicts MALO, HCC, liver transplant, and liver-related death. [Display omitted] [ABSTRACT FROM AUTHOR]

Background Ablation has become an important option for treatment of ventricular tachycardia (VT). The influence of procedure duration on outcomes remains unexamined. Objective The purpose of this study was to determine the influence of procedure duration on outcomes and complications over an 8-year period Methods Patients referred for scar-mediated VT ablation from 2004 to 2011 were retrospectively analyzed. Procedure duration was defined as the time from the insertion of catheters through the femoral vein to the time of their withdrawal. Procedure duration was analyzed in relationship with baseline and intraoperative covariates, acute procedural outcomes, complications, and 6-month clinical outcomes. Results One hundred forty-eight patients underwent VT ablation with mean procedure duration of 5.7 ± 1.8 hours. VT recurrence and survival at 6 months were 46% and 82%, respectively, and were not associated with procedure duration. Hospital mortality increased with intraoperative intraaortic balloon pump insertion (adjusted odds ratio [OR] 13.7, 95% confidence interval [CI] 2.35–79.94, P = .004) and was improved with successful ablation of the clinical VT as a procedural end-point (adjusted OR 0.13, 95% Cl 0.03–0.54, P = .005). The association between procedure duration and hospital mortality remained after adjusting for significant baseline variables (adjusted OR 1.75, 95% CI 1.14–2.68, P = .0098) and intraoperative variables (adjusted OR 1.6, 95% CI 1.12–2.29, P = .0104). Conclusion Hospital mortality was significantly increased by unsuccessful clinical VT ablation as a procedural end-point and intraoperative intraaortic balloon pump insertion. However, after adjusting for significant baseline and intraoperative covariates, procedure duration still was associated with increased hospital mortality. Procedure duration had no impact on VT recurrence and survival at 6 months. [ABSTRACT FROM AUTHOR]

Background: Electroanatomic mapping systems are an important tool to identify cardiac chamber voltage and assess channels of slow conduction. Objective: To assess the correlation between electroanatomic mapping voltage maps obtained during macroreentrant tachycardia compared to sinus rhythm (SR) with a contact mapping system. Methods: We retrospectively evaluated patients with atrial flutter (AFL) referred for radiofrequency ablation with electroanatomic voltage maps obtained during AFL and SR. The atrium was divided into predetermined segments. Overall atrial and segmental peak-to-peak bipolar voltages in AFL and SR were assessed. To directly compare a region within the same patient, tissue voltage differences during AFL and SR were assessed on the basis of mean voltage difference. Results: Sixteen patients (87% men) had available voltage maps. Eighty-one percent had typical cavotricuspid isthmus-dependent right AFL. A mean of 441.7±153.9 vs 398.1±125.4 total points (P = .22) were sampled during AFL and SR, with a mean of 99.5±58.9 vs 91.2±60.4 points (P = .45) sampled per region. Overall right atrial mean voltage was significantly higher during AFL than SR (0.554±0.092mV vs 0.473±0.079mV; P≤.001), with the lateral wall (0.707±0.120mV vs 0.573±0.097mV; P = .0004) and the cavotricuspid isthmus (0.559±0.100mV vs 0.356±0.066mV; P<.0001) also showing higher mean voltage during AFL. When compared within an individual patient, 19% (14 of 75) of the patient regions had a>0.5mV mean voltage difference and 40% (30 of 75) had a>0.25mV mean voltage difference. Conclusions: These data suggest that voltage maps performed during macroreentrant atrial arrhythmias often vary significantly from maps obtained during SR. [Copyright &y& Elsevier]

Abstract: Background:: Osteoporosis results in >1.5 million fractures in the United States each year, leading to substantial health care costs and loss of quality of life. One major gap in our knowledge is how to effectively identify individuals at risk of developing a fracture. Objective:: We examined a population-based cohort for risk factors for fractures of the hip, wrist, and spine in men and women. Methods:: The Leisure World Cohort Study was established between 1981 and 1985 when residents of a southern California retirement community completed a postal health survey. Multiple lifestyle, medical, attitudinal, and anthropomorphic factors were self-reported. Fractures were identified from 4 follow-up surveys, hospital discharge records, and death certificates. Fracture rates were determined separately for men and women. Cox proportional hazards regression was used to identify predictors of fracture. Results:: Incident fractures of the hip (n = 1227), wrist (n = 445), and spine (n = 729) incurred over the course of 2 decades were identified in the 13,978 residents surveyed. Mean (SD) age at entry was 74.9 (7.2) years for men and 73.7 (7.4) years for women. The most important risk factors for fracture were the same in men and women: age increased risk of hip and spine fractures (hazard ratio [HR] = 2.3–3.2 per 10 years) and history of fracture increased fracture risk at all 3 sites (HR = 1.4–3.2). In both men and women, glaucoma was a significant risk factor for hip fracture (HR = 1.9 and 1.3, respectively), and smoking was a risk factor for hip and spine fractures. Men and women with a positive mental attitude had fewer hip and spine fractures (HR = 0.7–0.9). High body mass index was protective at all 3 fracture sites in women (HR = 0.7–0.8), but those who used vitamin A supplements had increased rates of hip and wrist fracture (HR = 1.1 per 10,000 IU per day). Conclusions:: Attitude, lifestyle choices, and the presence of medical conditions may influence the rate of osteoporotic fracture in older women and men and may help identify individuals at high risk. [Copyright &y& Elsevier]

Background & Aims: Standard care for prevention of first esophageal variceal hemorrhage is β-blockade, but this may be ineffective or unsafe. Our purpose was to compare endoscopic banding with propranolol for prevention of first variceal hemorrhage. Methods: In a multicenter, prospective trial, 62 patients with cirrhosis with high-risk esophageal varices were randomized to propranolol (titrated to reducing resting pulse by ≥25%) or banding (performed monthly until varices were eradicated) and were followed up on the same schedule for a mean duration of 15 months. The primary end point was treatment failure, defined as the development of endoscopically documented variceal hemorrhage or a severe medical complication requiring discontinuation of therapy. Direct costs were estimated from Medicare reimbursements and fixed or variable charges for services up to treatment failure. Results: Background variables of the treatment groups were similar. The trial was stopped early after an interim analysis showed that the failure rate of propranolol was significantly higher than that of banding (6/31 vs. 0/31; difference, 19.4%; P = .0098; 95% confidence interval for true difference, 6.4%–37.2%). Significantly more propranolol than banding patients had esophageal variceal hemorrhage (4/31 vs. 0/31; difference, 12.9%; P = .0443; 95% confidence interval for true difference, 0.8%–29%), and the cumulative mortality rate was significantly higher in the propranolol than in the banding group (4/31 vs. 0/31; difference, 12.9%; P = .0443; 95% confidence interval for true difference, 0.8%–29%). Direct costs of care were not significantly different. Conclusions: For patients with cirrhosis with high-risk esophageal varices and no history of variceal hemorrhage, propranolol-treated patients had significantly higher failure rates of failure, first esophageal varix hemorrhage, and cumulative mortality than banding patients. Direct costs of medical care were not significantly different. [Copyright &y& Elsevier]

Background: The cesarean rate has served an integral role in the monitoring of obstetrical care, and in 2002, the national rate reached 26.1%, the highest ever reported.Objective: We sought to describe the effect of clinical complications on hospital cesarean rates.Research Design: This was a population-based cohort study.Subjects: All laboring women without a previous cesarean who delivered in California in 1995 as reported through public-use hospital discharge data were included.Measures: Women with and without maternal, fetal, or placental complications were compared with respect to cesarean use. Using recursive partitioning algorithms, women with complications were stratified into clinically homogeneous categories, which were analyzed separately with respect to cesarean use.Results: The 443,532 women delivered at 288 hospitals and included 116,170 women (26.2%) in the complicated group (cesarean rate 22.6%); and 327,362 women (73.8%) in the uncomplicated group (cesarean rate 6.7%). At the hospital level, the cesarean rates among the complicated and uncomplicated patients respectively were: median 23.5% (range, 2.2-9.9%); and median 6.5% (range, 1.8-18.2%). Recursive partitioning algorithms suggested 16 distinct clinical categories, with cesarean rates varying from 8.9% for women with asthma to 84.5% for women with an unengaged fetal head.Conclusions: Cesarean rates varied widely across complication types, and complication-specific rates varied widely among hospitals. Although the presence of pregnancy complications upon hospital admission comprised the strongest factor affecting first-time cesarean use among laboring women, the importance and interdependence of these clinical conditions has yet to be incorporated into commonly used models for cesarean rate comparisons. [ABSTRACT FROM AUTHOR]

No prior randomized controlled trial (RCT) has reported patient outcomes of large over-the-scope clip (OTSC) compared to standard hemostasis as initial endoscopic treatment of severe NVUGIB. This was our study aim. Patients with bleeding ulcers or Dieulafoy's lesions and major stigmata of hemorrhage - SRH (active spurting bleeding, visible vessel, or clot) - or lesser SRH (oozing bleeding or flat spots – with arterial blood flow by Doppler probe) were randomized to OTSC or standard endoscopic hemostasis (with hemoclips or multipolar electrocoagulation – MPEC). Patients and their healthcare providers were blinded to treatments and made all post-randomization management decisions. Ulcer patients received high dose intravenous infusions of proton pump inhibitors (PPI) for 3 days, then 27 days of oral PPI. 30 day outcomes were prospectively recorded; data management was with SAS; and data analysis was by a statistician. 53 patients (25 OTSC, 28 Standard) were randomized, with similar baseline risk factors. However, there were significant differences in OTSC vs. Standard groups in rates of rebleeding (4% vs. 28.6%; p =.017; relative risk 0.10, 95% confidence intervals 0.01, 0.91; number needed to treat 4); severe complications (0 % vs. 14.3%); and post-randomization units of red cell transfusions (0.04 vs. 0.68). All rebleeds occurred in patients with major SRH and none with lesser SRH. 1. OTSC significantly reduced rates of rebleeding, severe complications, and post-randomization red cell transfusions. 2. Patients with major stigmata benefited significantly from hemostasis with OTSC, but those with lesser stigmata did not. (ClinicalTrials.gov , Number: NCT03065465). [ABSTRACT FROM AUTHOR]