Cerebral Blood Flow, Brain Injury, and Aortic-Pulmonary Collateral Flow After the Fontan Operation

Patients with a single ventricle develop aortopulmonary collaterals (APCs) whose flow has been shown to be inversely proportional to cerebral blood flow (CBF) in a previous cross-sectional study. Longitudinal CBF and APC flow in patients with Fontan physiology adjusting for brain injury (BI) has never been reported. Decreased CBF and BI may adversely impact neurodevelopment. A prospective longitudinal cohort of 27 patients with Fontan physiology (aged 10 ± 1.9 years, 74% male) underwent cardiac and brain magnetic resonance imaging 3 to 9 months and 6.0 ± 1.86 years after Fontan operation to measure the CBF and APC flow and to reassess the BI (focal BI, generalized insult, and hemorrhage). CBF was measured using jugular venous flow and APC flow was measured by the difference between aortic flow and caval return. Multivariate modeling was used to assess the relation between the change in APC flow and BI. A strong inverse relation was found between CBF/aortic flow change and APC flow/aortic flow and APC flow/body surface area change (R2 = 0.70 and 0.72 respectively, p <0.02). Overall, the CBF decreased by 9 ± 11% and the APC flow decreased by 0.73 ± 0.67 l/min/m2. The evolution of CBF and APC flow were significantly and inversely related when adjusting for time since Fontan operation, gender, and BI on the multivariate modeling. Every unit increase in APC flow change was associated with an 8% decrease in CBF change. In conclusion, CBF and APC flow change are inversely related across serial imaging, adjusting for time from Fontan operation, gender, and BI. CBF and APC aortic flow decrease over a 6-year period. This may adversely impact neurodevelopment. Because APCs can be embolized, this may be a modifiable risk factor. Clinical trials numbers: NCT02135081 and NCT02919956.

Are excluding e-cigarettes a loophole in the smokefree public housing rule?

The U.S. Department of Housing and Urban Development (HUD) required all Public Housing Authorities to become smokefree in July 2018, following an 18-month implementation period that began February 2017. The HUD rule included all combustible tobacco products; e-cigarettes were not included. This purpose of this study is to characterize e-cigarette use overall and initiation after the implementation of the smokefree rule among tobacco users living in public housing. Data were collected from 396 adult (18+ years) current tobacco users at the time of rule implementation residing in the District of Columbia Housing Authority between July 2018 and November 2021. Measures include e-cigarette use, age of initiation, reasons for e-cigarette use, e-cigarette use susceptibility (among non-users), and sociodemographic characteristics. Descriptive and crosstab statistics were calculated to characterize e-cigarette use. Nearly-one-quarter of tobacco users reported lifetime use of e-cigarettes (24 %, n = 95) and 4.8 % (n = 19) indicated past 30-day e-cigarette use. Of the lifetime users, twenty-two (23.2 %) initiated their use after the smoke-free rule went into effect, with only two of those residents indicating they did so because of the rule. Of those who never used an e-cigarette, 23.5 % (n = 70) indicated being curious about e-cigarettes and 10.7 % (n = 40) said they may use e-cigarettes in the next year. Results indicate low use of e-cigarette products and low uptake due to the rule. Few tobacco users who never used e-cigarettes indicated intentions to use. Results suggest that omitting e-cigarettes from the HUD rule has not led to significant use of these products in this sample.

Low Xanthophylls, Retinol, Lycopene, and Tocopherols in Grey and White Matter of Brains with Alzheimer's Disease

BACKGROUND

Oxidative stress contributes to pathogenesis and progression of Alzheimer's disease (AD). Higher levels of the dietary antioxidants- carotenoids and tocopherols- are associated with better cognitive functions and lower risk for AD, and lower levels of multiple carotenoids are found in serum and plasma of patients with AD. Although brains donated by individuals with mild cognitive impairment had significantly lower levels of lutein and beta-carotene, previous investigators found no significant difference in carotenoid levels of brains with AD and cognitively normal brains.

OBJECTIVE

This study tested the hypothesis that micronutrients are significantly lower in donor brains with AD than in healthy elderly brains.

METHODS

Samples of donor brains with confirmed AD or verified health were dissected into grey and white matter, extracted with organic solvents and analyzed by HPLC.

RESULTS

AD brains had significantly lower levels of lutein, zeaxanthin, anhydrolutein, retinol, lycopene, and alpha-tocopherol, and significantly increased levels of XMiAD, an unidentified xanthophyll metabolite. No meso-zeaxanthin was detected. The overlapping protective roles of xanthophylls, carotenes, α- and γ-tocopherol are discussed.

CONCLUSION

Brains with AD had substantially lower concentrations of some, but not all, xanthophylls, carotenes, and tocopherols, and several-fold higher concentrations of an unidentified xanthophyll metabolite increased in AD (XMiAD).

Predictive Capability of Metabolic Panels for Postoperative Atrial Fibrillation in Cardiac Surgery Patients

INTRODUCTION

Postoperative atrial fibrillation (POAF) occurs in up to 65% of cardiac surgery patients and is associated with an increased risk for stroke and mortality. Electrolyte disturbances in sodium (Na+), potassium (K+), total calcium (Ca2+), chloride (Cl-), and magnesium (Mg2+) are predisposing factors for POAF, but these imbalances are yet to be used to predict POAF. The purpose of this study is to determine whether the development of POAF can be predicted by blood plasma ionic composition.

METHODS

Metabolic panels of patients with no prior history of atrial fibrillation who did (n = 763) and did not develop POAF (n = 2144) after cardiac surgery were obtained from the Carilion Clinic electronic medical record system. We initially evaluated serum Na+, K+, Ca2+, Cl-, and Mg2+ in the two groups using descriptive statistics via scatter and spaghetti plots and then with predictive modeling via logistic regression and random forest models.

RESULTS

Neither scatter nor spaghetti plots of electrolyte data revealed a significant difference between those who did and did not develop POAF. Two logistic regression models and two random forest models with POAF status as the outcome were generated using the first observation for each electrolyte and the coefficient of the linear regression, which was obtained from a linear fit of the scatter plot. The random forest model using the first observation had a sensitivity of only 12.2%, but all four models had specificities more than 97%.

CONCLUSIONS

Neither of the two logistic regression nor two random forest models were able to effectively predict the development of POAF from plasma ionic concentrations, but the random forest models effectively classified patients who would not develop POAF.

Examination of the Moderating Effect of Race on the Relationship between Vitamin D Status and COVID-19 Test Positivity Using Propensity Score Methods

INTRODUCTION

With a well-established role in inflammation and immune function, vitamin D status has emerged as a potential factor for coronavirus disease-2019 (COVID-19).

OBJECTIVE

The purpose of this study was to evaluate the moderating effect of race on the relationship between vitamin D status and the risk of COVID-19 test positivity, and to compare propensity score (PS) model results to those obtained from classical bivariate and multivariable models, which have primarily comprised the literature to date.

METHODS

Electronic health record (EHR) data from TriNetX (unmatched n = 21,629; matched n = 16,602) were used to investigate the effect of vitamin D status, as measured by 25-hydroxyvitamin D [25(OH)D], on the odds of experiencing a positive COVID-19 test using multivariable logistic regression models with and without PS methodology.

RESULTS

Having normal (≥ 30 ng/mL) versus inadequate 25(OH)D (< 30 ng/mL) was not associated with COVID-19 positivity overall (OR = 0.913, p = 0.18), in White individuals (OR = 0.920, p = 0.31), or in Black individuals (OR = 1.006, p = 0.96). When 25(OH)D was analyzed on a continuum, a 10 ng/mL increase in 25(OH)D lowered the odds of having a positive COVID-19 test overall (OR = 0.949, p = 0.003) and among White (OR = 0.935, p = 0.003), but not Black individuals (OR = 0.994, p = 0.75).

CONCLUSIONS

Models which use weighting and matching methods resulted in smaller estimated effect sizes than models which do not use weighting or matching. These findings suggest a minimal protective effect of vitamin D status on COVID-19 test positivity in White individuals and no protective effect in Black individuals.

Behavioural intentions in response to a potential menthol cigarette sales ban: a survey examining smokers in Washington, DC public housing

OBJECTIVES

Local, national and international policies are being proposed to ban the sale of menthol-flavoured tobacco products. With more bans being implemented, it is increasingly important to understand reactions to these bans among smokers of low socioeconomic status. This study examined public housing residents' behavioural intentions if menthol-flavoured cigarettes were no longer sold.

SETTING

15 District of Columbia Housing Authority properties between March 2019 and March 2021.

PARTICIPANTS

221 District of Columbia Housing Authority residents ages 18-80 years who reported smoking menthol cigarettes (83.3% African-American/black).

PRIMARY AND SECONDARY OUTCOMES

Cigarette quitting and switching intentions due to a hypothetical menthol-flavoured cigarette sales ban.

RESULTS

Nearly one-half (48.0%) of residents said they intended to quit cigarette use if menthol-flavoured products were no longer sold, while 27.2% were unsure if they would quit, and 24.9% reported they would not quit. Older residents (OR 0.94 per year, 95% CI 0.91 to 0.97), senior/disabled building versus family building residents (OR 0.50, 95% CI 0.25 to 0.97), those who smoked within 30 min of waking (OR 0.48, 95% CI 0.23 to 0.98) and daily smokers (OR 0.42, 95% CI 0.21 to 0.84) had lower odds of reporting quit intentions associated with a menthol ban. Of those not intending to quit, 40.7% reported they would switch to non-menthol cigarettes, 20.4% to another non-menthol product, 13.0% to menthol e-cigarettes and 20.4% to another menthol product.

CONCLUSIONS

Results suggest banning the sale of menthol-flavoured products has the potential to impact cigarette smoking cessation. Nearly three-quarters of smokers in public housing indicated a possibility of quitting smoking because of a menthol cigarette ban. Bans that include all flavours in all tobacco products may be most effective for facilitating overall tobacco cessation.

Individual Health Determinants that Predict Low Risk of Transitioning to Tobacco Use During Young Adulthood: An in-Depth Examination of Race and Ethnicity

Introduction

The present study examines the contributions of individual-level health determinants on young adult tobacco use initiation to improve understanding of racial and ethnic distinctions and to inform effective tobacco prevention strategies.

Methods

Using time-to-event analyses, the 10–wave (2011–2016) Truth Initiative Young Adult Cohort, a probability-based, nationally representative sample of the US young adults aged 18–34 years (N = 7 665), provides data to examine differences in variables that influence tobacco uptake, by race and ethnicity.

Results

Among Non–Hispanic White young adults, having fewer peers who smoke cigarettes is protective against any tobacco initiation, whereas hazard of tobacco initiation increases for males, having low confidence to resist smoking, and having higher proclivity for sensation seeking. Depressive and anxiety symptoms increase uptake hazard most in the Non–Hispanic All Other Races group and least among Non–Hispanic Black individuals. Among Hispanic young adults, being female and perceiving tobacco as harmful are notably protective while being male is a notable uptake hazard. Unlike other groups, higher income levels do not lower hazards among Hispanic individuals. Cannabis use and overestimating the smoking rate among peers increase hazard least among Hispanic individuals. In the Non–Hispanic All Other Races group, aging is least protective; hazard increases notably if individuals engage in regular alcohol or cannabis use.

Conclusions

Tobacco prevention efforts are critical during young adulthood. Specific tobacco uptake hazard and protective factors exist by race and ethnicity and should be considered when developing selective young adult prevention, particularly among groups with the highest risk for tobacco initiation during this life stage.

Implications

Rising rates of tobacco initiation among the US young adults necessitate expanded efforts to prevent tobacco use initiation and progression beyond youth. Results highlight nuanced and differential tobacco uptake hazards by race and ethnicity for late initiation and sustained non–tobacco use among young adults. The study confirms existing evidence on tobacco use patterns and contributes to new knowledge on risk and protective factors. Tobacco prevention and control interventions, including policies, tailored in more meaningful ways could reduce tobacco use disparities among those most disproportionately affected.

Smoking cessation intentions and attempts one year after the federally mandated smoke-free housing rule

The present study examines public housing residents' smoking cessation intentions, expectancies, and attempts one year after implementation of the Department of Housing and Urban Development's mandatory smoke-free rule in public housing. The sample includes 233 cigarette smokers, ages 18-80, who reside in the District of Columbia Housing Authority. Data collection occurred between March and August 2019. Descriptive statistics, chi-square, and Wilcoxon two-sample test analyses assessed smoking cessation intentions, expectancies, and attempts across resident demographics and characteristics. Findings showed 17.2% of residents reported not thinking about quitting, 39.1% reported thinking about quitting, and 48.6% reported thinking about quitting specifically because of the rule. Residents ages 60-80 were more likely to consider quitting because of the rule, compared to residents ages 18-59. Of those thinking of quitting, 58.6% were sure they could quit if they tried. Those thinking of quitting due to the rule (62.0%) were more likely to have made at least one quit attempt in the past 3 months than those i not attributinging thinking of quitting to the rule. Res Residents trying to quit reported an average of 2.7 attempts in the last 3 months;; most perceived evidence-based cessation supports as not helpful. A A majority reported thinking about quitting and attempting to quit but continuing to smoke, indicating a significant gap between intent to quit and successfully quitting. Results suggest that the rule positively influenced smoking behaviors. However, additional interventions are needed to assist public housing residents with successfully quitting smoking.

The conduction velocity-potassium relationship in the heart is modulated by sodium and calcium

The relationship between cardiac conduction velocity (CV) and extracellular potassium (K⁺) is biphasic, with modest hyperkalemia increasing CV and severe hyperkalemia slowing CV. Recent studies from our group suggest that elevating extracellular sodium (Na⁺) and calcium (Ca²⁺) can enhance CV by an extracellular pathway parallel to gap junctional coupling (GJC) called ephaptic coupling that can occur in the gap junction adjacent perinexus. However, it remains unknown whether these same interventions modulate CV as a function of K⁺. We hypothesize that Na⁺, Ca²⁺, and GJC can attenuate conduction slowing consequent to severe hyperkalemia. Elevating Ca²⁺ from 1.25 to 2.00 mM significantly narrowed perinexal width measured by transmission electron microscopy. Optically mapped, Langendorff-perfused guinea pig hearts perfused with increasing K⁺ revealed the expected biphasic CV-K⁺ relationship during perfusion with different Na⁺ and Ca²⁺ concentrations. Neither elevating Na⁺ nor Ca²⁺ alone consistently modulated the positive slope of CV-K⁺ or conduction slowing at 10-mM K⁺; however, combined Na⁺ and Ca²⁺ elevation significantly mitigated conduction slowing at 10-mM K⁺. Pharmacologic GJC inhibition with 30-μM carbenoxolone slowed CV without changing the shape of CV-K⁺ curves. A computational model of CV predicted that elevating Na⁺ and narrowing clefts between myocytes, as occur with perinexal narrowing, reduces the positive and negative slopes of the CV-K⁺ relationship but do not support a primary role of GJC or sodium channel conductance. These data demonstrate that combinatorial effects of Na⁺ and Ca²⁺ differentially modulate conduction during hyperkalemia, and enhancing determinants of ephaptic coupling may attenuate conduction changes in a variety of physiologic conditions.

Record Linkage Reconciliation of Arlington Department of Human Services Administrative Data Using Potts Models

Situated at the nexus of federal, state, and local governments, the Arlington Department of Human Services (DHS) receives service utilization data from a multitude of different sources. Because of their “no wrong door” policy, customers can sign up for any DHS service from any DHS department. A practical consequence of this is that a single person can appear as multiple records from multiple databases with no unambiguous key between these records. Merging these records requires a probabilistic linkage approach. Classical approaches to record linkage, such as the method of Felligi and Sunter, consider each possible pair of records between databases and assigning link probabilities to each one. A drawback of considering pairwise links alone is that sometimes the transitive nature of links is violated. In order to better handle such information clashes, we propose a Bayesian linkage method that considers a large set of possible pairs at once. At the heart of this approach is a Potts model representation that tracks which records are assigned to the same individual. This allows us to assign probabilities to the various reconciliations of inconsistent linkage assignments.

Observation-Level and Parametric Interaction for High-Dimensional Data Analysis

Exploring high-dimensional data is challenging. Dimension reduction algorithms, such as weighted multidimensional scaling, support data exploration by projecting datasets to two dimensions for visualization. These projections can be explored through parametric interaction, tweaking underlying parameterizations, and observation-level interaction, directly interacting with the points within the projection. In this article, we present the results of a controlled usability study determining the differences, advantages, and drawbacks among parametric interaction, observation-level interaction, and their combination. The study assesses both interaction technique effects on domain-specific high-dimensional data analyses performed by non-experts of statistical algorithms. This study is performed using Andromeda, a tool that enables both parametric and observation-level interaction to provide in-depth data exploration. The results indicate that the two forms of interaction serve different, but complementary, purposes in gaining insight through steerable dimension reduction algorithms.

Towards a Systematic Combination of Dimension Reduction and Clustering in Visual Analytics

Dimension reduction algorithms and clustering algorithms are both frequently used techniques in visual analytics. Both families of algorithms assist analysts in performing related tasks regarding the similarity of observations and finding groups in datasets. Though initially used independently, recent works have incorporated algorithms from each family into the same visualization systems. However, these algorithmic combinations are often ad hoc or disconnected, working independently and in parallel rather than integrating some degree of interdependence. A number of design decisions must be addressed when employing dimension reduction and clustering algorithms concurrently in a visualization system, including the selection of each algorithm, the order in which they are processed, and how to present and interact with the resulting projection. This paper contributes an overview of combining dimension reduction and clustering into a visualization system, discussing the challenges inherent in developing a visualization system that makes use of both families of algorithms.

Outlier Detection for Sensor Systems (ODSS): A MATLAB Macro for Evaluating Microphone Sensor Data Quality

Microphone sensor systems provide information that may be used for a variety of applications. Such systems generate large amounts of data. One concern is with microphone failure and unusual values that may be generated as part of the information collection process. This paper describes methods and a MATLAB graphical interface that provides rapid evaluation of microphone performance and identifies irregularities. The approach and interface are described. An application to a microphone array used in a wind tunnel is used to illustrate the methodology.

Medical adherence to acne therapy: a systematic review

BACKGROUND

Poor adherence of acne patients to treatment may equate to poor clinical efficacy, increased healthcare costs, and unnecessary treatments. Authors have investigated risk factors for poor medical adherence and how to improve this difficult problem in the context of acne.

OBJECTIVE

This systematic review aims to describe what methods have been used to measure adherence, what is known about acne patients' adherence to treatment, and the factors affecting adherence.

METHODS

A MEDLINE search was performed for randomized controlled trials published between 1978 and June 2013, focusing on patient adherence to prescribed acne medications. A test for equality of proportions was performed on studies of similar design to collectively analyze adherence to oral versus topical medication. The self-reported adherence data collected from these clinical trials were then compared with adherence data from a pharmacy database study.

RESULTS

Studies varied in modalities of data collection, but the majority utilized subjective methods. Topical therapies were more often studied than oral. The overall oral adherence rate, as calculated by a test of equality of proportions, was 76.3%, while the overall topical adherence rate was 75.8% (p=0.927). The occurrence of side effects and young age were cited as the top reasons for poor adherence, followed by forgetfulness.

LIMITATIONS

The MEDLINE search resulted in a limited sample of adherence studies. In addition, there is currently no standardized or fully validated method of measurement, allowing for variability in what was considered 'adherent'. Lastly, data collected via subjective methods cannot guarantee reliable results.

CONCLUSIONS

Overall, the values reflected a population adherent to both topical and oral medications, with no significant difference in adherence between the two. However, the methodologies used by many of the studies were weak, and the findings are not consistent with results of more objective measures of adherence. The leading factors that contribute to poor adherence may be reduced with enhanced patient consultation, reminder systems, and education.