Comparison of Radial Echoendoscopy and Predictive Factors in the Evaluation of Patients with Suspected Choledocholithiasis

Objective: The aim of this study was to compare predictive factors and Radial Echoendoscopy (EUS) in the diagnosis of choledocholithiasis.Materials and Methods: Patients with suspected choledocholithiasis were recruited from April 2011 to January 2018. All patient characteristics, findings of EUS and findings of ERCP were recorded and analyzed.Results: Eighty patients were enrolled in this study. Clinical symptoms, blood chemistry and liver function test were similar in patients with and without choledocholithiasis. Using the findings of ERCP as the gold standard, Radial EUS had sensitivity and specificity for the detection of choledocholithiasis at 90.2% and 97.4%, and for choledocholithiasis and/or common bile duct sludge at 92.7% and 100%, respectively. For patients with intermediate likelihood and high likelihood from predictive factors (33 and 45), Radial EUS was positive for choledocholithiasis in 51.5% (17/33) and 46.7% (21/45), and ERCP was positive for choledocholithiasis in 54.5% (18/33) and 48.9% (22/45), respectively.Conclusion: Predictive factors, for both intermediate and high likelihood groups, were not accurate to diagnose these patients. Radial EUS is a good diagnostic tool and should done in both groups of patients to avoid unnecessary ERCP.

246 Maintenance of Circadian/Daily Activity Patterns and Cognitive Resilience to Alzheimer’s Pathology in Late Life

Introduction Many individuals remain free from dementia despite substantial plaque and tangle deposits, the hallmarks of Alzheimer’s disease (AD). Understanding of this cognitive resilience is poor. Evidence suggests that circadian disturbances predict increased risk of incident AD, and that circadian regulation deteriorates as clinical AD progresses. We hypothesize that circadian robustness protects against dementia, and the effect is stronger in individuals with AD pathology than those without. Methods We studied 575 deceased participants (age at death: 91.1□6.2; female: 414) in the Rush Memory and Aging Project who underwent brain autopsy at death, had clinical diagnostic opinion of dementia and motor activity assessments with actigraphy of ~10 days before death. Using actigraphy proximate to death, we calculated four circadian metrics: amplitude, acrophase, interdaily stability, and intradaily variability. Logistic regressions, stratified by postmortem pathologic AD diagnosis, were used to examine associations of circadian metrics with odds of dementia, and separately cognitive impairment (CI, including both dementia and mild cognitive impairment [MCI]), adjusting for age at death, sex, education, and time-lag between actigraphy and death. Results Based on postmortem assessment, 378 participants met the NIA-Reagan criteria for high/intermediate likelihood AD (AD group), including 197 clinically diagnosed with dementia, 86 MCI, and 85 cognitively intact. Non-AD group consisted of the remaining 197 participants, including 36 with clinical dementia, 47 MCI, and 114 cognitively intact. In the AD group, greater amplitude, greater interdaily stability, and lower intradaily variability were associated with lower odds of CI and dementia, i.e., odds ratios [OR] for CI corresponding to 1-SD changes were 0.54 (95% CI: 0.40-0.71), 0.70 (0.54-0.91), and 0.63 (0.47-0.84), and were 0.46 (0.35-0.60), 0.55 (0.43-0.70), and 0.61 (0.48-0.78) for dementia. In the non-AD group, only amplitude was associated with the odds of CI or dementia, i.e., the ORs corresponding to 1-SD increase was 0.61 (0.42-0.88) and 0.50 (0.31-0.82), respectively. Conclusion Better preserved circadian function, as characterized by more pronounced, more stable and less fragmented rest-activity rhythms, links to lower risk of CI or dementia in older people, especially those with pathological AD. Support (if any) NIH RF1AG064312, RF1AG059867, R01AG017917, R01AG56352; and the BrightFocus Foundation A2020886S.

Intermediate Likelihood of Choledocholithiasis: Do All Need EUS or MRCP?

Background Recently updated guidelines for choledocholithiasis stratify suspected patients into high, intermediate, and low likelihood, with the aim to reduce risk of diagnostic endoscopic retrograde cholangiopancreatography. This approach has increased proportion of patients in intermediate likelihood making it heterogenous. We aim to substratify intermediate group so that diagnostic tests (endoscopic ultrasound/magnetic resonance cholangiopancreatography) are judicially used. Methods This is a single-center retrospective analysis of prospectively maintained data. We used subset of patients who met intermediate likelihood of American Society of Gastrointestinal Endoscopy (ASGE) criteria from previously published data (PMID:32106321) as derivation cohort. Binominal logistic regression analysis was used to define independent predictors of choledocholithiasis. A composite score was derived by allotting 1 point for presence of each independent predictor. The diagnostic performance of a composite score of ≥ 1 was evaluated in validation cohort. Results A total of 678 (mean age [standard deviation]: 47.0 [15.9] years; 48.1% men) and 162 (mean age 47.8 [14.8] years; 47.4% men) patients in ASGE intermediate-likelihood group were included as derivation cohort and validation cohort, respectively. Binominal logistic regression analysis showed that male gender (p = 0.024; odds ratio [OR] = 1.92), raised bilirubin (p = 0.001; OR = 2.40), and acute calculus cholecystitis (p = 0.010; OR = 2.04) were independent predictors for choledocholithiasis. A composite score was derived by allotting 1 point for presence of independent predictors Using ≥ 1 as cutoff, sensitivity and specificity for detection of choledocholithiasis were 80% (95% confidence interval [CI]: 68.2–88.9) and 36.2% (95% CI: 32.2–40.0), respectively, in derivation cohort. Applying composite score in independent validation cohort showed sensitivity and specificity of 73.3% (95% CI: 44.9–92.2) and 40.1% (95% CI: 30.1–48.5), respectively. Conclusion Substratification of intermediate-likelihood group of ASGE criteria is feasible. It may be useful in deciding in whom confirmatory tests should be performed with priority and in whom watchful waiting may be sufficient.

Adaptive targeted infectious disease testing

We show how to efficiently use costly testing resources in an epidemic, when testing outcomes can be used to make quarantine decisions. If the costs of false quarantine and false release exceed the cost of testing, the optimal myopic testing policy targets individuals with an intermediate likelihood of being infected. A high cost of false release means that testing is optimal for individuals with a low probability of infection, and a high cost of false quarantine means that testing is optimal for individuals with a high probability of infection. If individuals arrive over time, the policy-maker faces a dynamic trade-off: using tests for individuals for whom testing yields the maximum immediate benefit vs spreading out testing capacity across the population to learn prevalence rates thereby benefiting later individuals. We describe a simple policy that is nearly optimal from a dynamic perspective. We briefly discuss practical aspects of implementing our proposed policy, including imperfect testing technology, appropriate choice of prior, and non-stationarity of the prevalence rate.

Abstract 16545: Gender Attitudes and the Use of Angiography Among Cardiologists

Background: Physician bias may contribute to gender disparities in the use of angiography. We performed the first study using the Implicit Association Test (IAT) to examine gender biases and their associations with angiography decisions. Methods: Cardiology physicians were emailed a web-based survey that included 2 gender-IATs and a two-part clinical vignette randomized by patient gender. The IATs measured attitudes about men versus women on strength and risk-taking. The vignette represented an intermediate likelihood of CAD regardless of gender; part-1 described a patient with symptoms of CAD and part-2 described an abnormal stress test. Physicians rated the likelihood of CAD and their agreement with the usefulness of angiography for that patient. We examined the association between gender attitudes and rated usefulness of angiography for the male and female patient, adjusting for the perceived likelihood of CAD. Results: Of the 503 cardiologists who responded, over half associated strength and willingness to take risks with males. For both parts of the case, cardiologists’ estimated the likelihood of CAD similarly by patient gender; yet, cardiologists’ more often rated the usefulness of angiography as “high” for the male versus female patient (Part-1: 19.7% vs. 9.8%; Part-2: 73.7% vs. 64.3%; p<0.05 for both). These differences varied by gender attitudes; those with higher male-risk bias or male-strength bias rated angiography as more useful for men than for women. (Figure) After adjustment, only the relationship with male-risk bias and higher angiography rating for male patients persisted (p=0.01 for interaction). Conclusions: Despite similar estimates of CAD likelihood, cardiology physicians rated the usefulness of angiography higher for a standardized male than female patient. This difference significantly varied by gender-risk bias suggesting the concept of riskiness influenced decisions about angiography differently in women and male patients.