Racial Disparities in Diabetes Care and Outcomes for Patients with Visual Impairment: A Descriptive Analysis of the TriNetX Research Network

Background: This research delves into the confluence of racial disparities and health inequities among individuals with disabilities, with a focus on those contending with both diabetes and visual impairment. Methods: Utilizing data from the TriNetX Research Network, which includes electronic medical records of roughly 115 million patients from 83 anonymous healthcare organizations, this study employs a directed acyclic graph (DAG) to pinpoint confounders and augment interpretation. We identified patients with visual impairments using ICD-10 codes, deliberately excluding diabetes-related ophthalmology complications. Our approach involved multiple race-stratified analyses, comparing co-morbidities like chronic pulmonary disease in visually impaired patients against their counterparts. We assessed healthcare access disparities by examining the frequency of annual visits, instances of two or more A1c measurements, and glomerular filtration rate (GFR) measurements. Additionally, we evaluated diabetes outcomes by comparing the risk ratio of uncontrolled diabetes (A1c > 9.0) and chronic kidney disease in patients with and without visual impairments. Results: The incidence of diabetes was substantially higher (nearly double) in individuals with visual impairments across White, Asian, and African American populations. Higher rates of chronic kidney disease were observed in visually impaired individuals, with a risk ratio of 1.79 for African American, 2.27 for White, and non-significant for the Asian group. A statistically significant difference in the risk ratio for uncontrolled diabetes was found only in the White cohort (0.843). White individuals without visual impairments were more likely to receive two A1c tests, a trend not significant in other racial groups. African Americans with visual impairments had a higher rate of glomerular filtration rate testing. However, White individuals with visual impairments were less likely to undergo GFR testing, indicating a disparity in kidney health monitoring. This pattern of disparity was not observed in the Asian cohort. Conclusions: This study uncovers pronounced disparities in diabetes incidence and management among individuals with visual impairments, particularly among White, Asian, and African American groups. Our DAG analysis illuminates the intricate interplay between SDoH, healthcare access, and frequency of crucial diabetes monitoring practices, highlighting visual impairment as both a medical and social issue.

Artificial intelligence-based clinical decision support for liver transplant evaluation and considerations about fairness: A qualitative study

BACKGROUND

The use of large-scale data and artificial intelligence (AI) to support complex transplantation decisions is in its infancy. Transplant candidate decision-making, which relies heavily on subjective assessment (ie, high variability), provides a ripe opportunity for AI-based clinical decision support (CDS). However, AI-CDS for transplant applications must consider important concerns regarding fairness (ie, health equity). The objective of this study was to use human-centered design methods to elicit providers' perceptions of AI-CDS for liver transplant listing decisions.

METHODS

In this multicenter qualitative study conducted from December 2020 to July 2021, we performed semistructured interviews with 53 multidisciplinary liver transplant providers from 2 transplant centers. We used inductive coding and constant comparison analysis of interview data.

RESULTS

Analysis yielded 6 themes important for the design of fair AI-CDS for liver transplant listing decisions: (1) transparency in the creators behind the AI-CDS and their motivations; (2) understanding how the AI-CDS uses data to support recommendations (ie, interpretability); (3) acknowledgment that AI-CDS could mitigate emotions and biases; (4) AI-CDS as a member of the transplant team, not a replacement; (5) identifying patient resource needs; and (6) including the patient's role in the AI-CDS.

CONCLUSIONS

Overall, providers interviewed were cautiously optimistic about the potential for AI-CDS to improve clinical and equitable outcomes for patients. These findings can guide multidisciplinary developers in the design and implementation of AI-CDS that deliberately considers health equity.

Enhancing the nation's public health information infrastructure: a report from the ACMI symposium

The COVID-19 pandemic exposed multiple weaknesses in the nation's public health system. Therefore, the American College of Medical Informatics selected "Rebuilding the Nation's Public Health Informatics Infrastructure" as the theme for its annual symposium. Experts in biomedical informatics and public health discussed strategies to strengthen the US public health information infrastructure through policy, education, research, and development. This article summarizes policy recommendations for the biomedical informatics community postpandemic. First, the nation must perceive the health data infrastructure to be a matter of national security. The nation must further invest significantly more in its health data infrastructure. Investments should include the education and training of the public health workforce as informaticians in this domain are currently limited. Finally, investments should strengthen and expand health data utilities that increasingly play a critical role in exchanging information across public health and healthcare organizations.

Trends and opportunities in computable clinical phenotyping: A scoping review

Identifying patient cohorts meeting the criteria of specific phenotypes is essential in biomedicine and particularly timely in precision medicine. Many research groups deliver pipelines that automatically retrieve and analyze data elements from one or more sources to automate this task and deliver high-performing computable phenotypes. We applied a systematic approach based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to conduct a thorough scoping review on computable clinical phenotyping. Five databases were searched using a query that combined the concepts of automation, clinical context, and phenotyping. Subsequently, four reviewers screened 7960 records (after removing over 4000 duplicates) and selected 139 that satisfied the inclusion criteria. This dataset was analyzed to extract information on target use cases, data-related topics, phenotyping methodologies, evaluation strategies, and portability of developed solutions. Most studies supported patient cohort selection without discussing the application to specific use cases, such as precision medicine. Electronic Health Records were the primary source in 87.1 % (N = 121) of all studies, and International Classification of Diseases codes were heavily used in 55.4 % (N = 77) of all studies, however, only 25.9 % (N = 36) of the records described compliance with a common data model. In terms of the presented methods, traditional Machine Learning (ML) was the dominant method, often combined with natural language processing and other approaches, while external validation and portability of computable phenotypes were pursued in many cases. These findings revealed that defining target use cases precisely, moving away from sole ML strategies, and evaluating the proposed solutions in the real setting are essential opportunities for future work. There is also momentum and an emerging need for computable phenotyping to support clinical and epidemiological research and precision medicine.

Abstract P401: Circadian Dietary Patterns and Weight Trajectories in Adults Using the Daily24 Mobile Application

Introduction: It is unclear whether the timing of meals relative to sleep impacts cardiometabolic risk factors (e.g., weight gain). This cohort study aimed to detect and describe the association of the timing of caloric intake and dietary patterns (e.g., skipping breakfast) with weight trajectory over 2 years among participants who used the Daily24 mobile application to record their timing of eating and sleeping.

Hypothesis: We hypothesized that skipping breakfast or consuming 50% or more of daily calories in the latter half of the day is associated with greater weight gain over 2 years.

Methods: We conducted a secondary data analysis from a multi-site, electronic health record-based cohort study of adults from 3 healthcare systems in PCORnet’s PaTH Clinical Research Network. Of the 1017 participants enrolled in the study, N=407 patients downloaded and used the Daily24 mobile application for at least 2 weekdays and 1 weekend day over 6 months. We calculated the median of each participant’s daily eating and sleeping intervals. Participants’ weights were extracted from electronic health records available for up to 10 years prior to until 10 months after baseline. Weight trajectories were calculated over 2 years of this data. Participants completed online surveys about demographics and behavioral characteristics at baseline and after 4 months. We constructed multivariate linear regression models with weight trajectory as the dependent variable and breakfast skipping (i.e., not eating anything within 3 hours of waking), having a medium or large meal within 3 hours of sleep, ≥50% caloric consumption in the latter half of the day (after 12 pm), and ≥90% caloric consumption after 7 pm as independent variables. Additional independent variables included age, sex, race, days of application use, and body mass index (BMI) category.

Results: Mean (SD) baseline age was 50.8 (15.0) years, 75.7% had a BMI≥25 kg/m 2 , 78.1% were women, and 84.0% were white. The average number of recorded Daily24 application days was 55.9 (53.5), significantly greater than the 3-day minimum inclusion criterion. The mean of participants’ median intervals from first to last meal was 11.2 (2.0) hours. Although not statistically significant, consuming 50% of daily calories in the latter half of the day and skipping breakfast were associated with an increasing weight trajectory (0.03 and 0.25 kg/year; 95% CI -0.39 to 0.45 and -0.32 to 0.82, respectively).

Conclusions: Timing of eating (e.g., skipping breakfast or eating most calories later in the day) may be associated with very small weight increases over time. Our app-based approach may not have had enough observations to establish this association. Further research is needed to understand the clinical importance of circadian dietary patterns related to cardiometabolic health.

Human-centered design of clinical decision support for anemia screening in children with inflammatory bowel disease

Background Inflammatory bowel disease (IBD) commonly leads to iron deficiency anemia (IDA). Rates of screening and treatment of IDA are often low. A clinical decision support system (CDSS) embedded in an electronic health record could improve adherence to evidence-based care. Rates of CDSS adoption are often low due to poor usability and fit with work processes. One solution is to use human centered design (HCD), which designs CDSS based on identified user needs and context of use and evaluates prototypes for usefulness and usability. Objectives Use HCD to design a CDSS tool called the IBD Anemia Diagnosis Tool, IADx. Methods Interviews with IBD practitioners informed creation of a process map of anemia care that was used by an interdisciplinary team that used HCD principles to create a prototype CDSS. The prototype was iteratively tested with "Think Aloud" usability evaluation with clinicians as well as semi-structured interviews, a survey, and observations. Feedback was coded and informed redesign. Results Process mapping showed that IADx should function at in-person encounters and asynchronous lab review. Clinicians desired full automation of clinical information acquisition such as lab trends and analysis such as calculation of iron deficit, less automation of clinical decision selection such as lab ordering and no automation of action implementation such as signing medication orders. Providers preferred an interruptive alert over a non-interruptive reminder. Discussion Providers preferred an interruptive alert, perhaps due to the low likelihood of noticing a non-interruptive advisory. High levels of desire for automation of information acquisition and analysis with less automation of decision selection and action may be generalizable to other CDSSs designed for chronic disease management. This underlines the ways in which CDSSs have the potential to augment rather than replace provider cognitive work.

Development of a Digital Assistant to Support Teleconsultations Between Remote Physicians and Frontline Health Workers in India: User-Centered Design Approach

BACKGROUND

Many low- and middle-income countries have adopted telemedicine programs that connect frontline health workers (FHWs) such as nurses, midwives, or community health workers in rural and remote areas with physicians in urban areas to deliver care to patients. By leveraging technology to reduce temporal, financial, and geographical barriers, these health worker-to-physician telemedicine programs have the potential to increase health care quality, expand the specialties available to patients, and reduce the time and cost required to deliver care.

OBJECTIVE

We aimed to identify, validate, and prioritize unmet needs in the health care space of health worker-to-physician telemedicine programs and develop and refine a solution that addresses those needs.

METHODS

We collected information regarding user needs through ethnographic research, direct observation, and semistructured interviews with 37 stakeholders (n=5, 14% physicians; n=1, 3% public health program manager; n=12, 32% community health workers; and n=19, 51% patients) at 2 telemedicine clinics in rural West Bengal, India. We used the Spiral-Iterative Innovation Model to design and develop a prototype solution to meet these needs.

RESULTS

We identified 74 unmet needs through our immersion in health worker-to-physician telemedicine programs. We identified a critical unmet need that achieving optimal teleconsultations in low- and middle-income countries often requires shifting tasks such as history taking and physical examination from high-skilled remote physicians to FHWs. To meet this need, we developed a prototype digital assistant that would allow FHWs to assume some of the tasks carried out by remote clinicians. The user needs of multiple stakeholder groups (patients, FHWs, physicians, and health organizations) were incorporated into the design and features of the task-shifting tool. The final prototype was shared with the health workers, physicians, and public health program managers who expressed that the tool would be useful and valuable.

CONCLUSIONS

The final prototype that was developed was released as an open-source digital public good and may improve the quality and efficiency of care delivery in health worker-to-physician telemedicine programs.

Association of Eating and Sleeping Intervals With Weight Change Over Time: The Daily24 Cohort

Background We aim to evaluate the association between meal intervals and weight trajectory among adults from a clinical cohort. Methods and Results This is a multisite prospective cohort study of adults recruited from 3 health systems. Over the 6-month study period, 547 participants downloaded and used a mobile application to record the timing of meals and sleep for at least 1 day. We obtained information on weight and comorbidities at each outpatient visit from electronic health records for up to 10  years before until 10 months after baseline. We used mixed linear regression to model weight trajectories. Mean age was 51.1 (SD 15.0) years, and body mass index was 30.8 (SD 7.8) kg/m²; 77.9% were women, and 77.5% reported White race. Mean interval from first to last meal was 11.5 (2.3) hours and was not associated with weight change. The number of meals per day was positively associated with weight change. The average difference in annual weight change (95% CI) associated with an increase of 1 daily meal was 0.28 kg (0.02-0.53). Conclusions Number of daily meals was positively associated with weight change over 6 years. Our findings did not support the use of time-restricted eating as a strategy for long-term weight loss in a general medical population.

A scoping review of knowledge authoring tools used for developing computerized clinical decision support systems

Objective

Clinical Knowledge Authoring Tools (CKATs) are integral to the computerized Clinical Decision Support (CDS) development life cycle. CKATs enable authors to generate accurate, complete, and reliable digital knowledge artifacts in a relatively efficient and affordable manner. This scoping review aims to compare knowledge authoring tools and derive the common features of CKATs.

Materials and Methods

We performed a keyword-based literature search, followed by a snowball search, to identify peer-reviewed publications describing the development or use of CKATs. We used PubMed and Embase search engines to perform the initial search (n = 1579). After removing duplicate articles, nonrelevant manuscripts, and not peer-reviewed publication, we identified 47 eligible studies describing 33 unique CKATs. The reviewed CKATs were further assessed, and salient characteristics were extracted and grouped as common CKAT features.

Results

Among the identified CKATs, 55% use an open source platform, 70% provide an application programming interface for CDS system integration, and 79% provide features to validate/test the knowledge. The majority of the reviewed CKATs describe the flow of information, offer a graphical user interface for knowledge authors, and provide intellisense coding features (94%, 97%, and 97%, respectively). The composed list of criteria for CKAT included topics such as simulating the clinical setting, validating the knowledge, standardized clinical models and vocabulary, and domain independence. None of the reviewed CKATs met all common criteria.

Conclusion

Our scoping review highlights the key specifications for a CKAT. The CKAT specification proposed in this review can guide CDS authors in developing more targeted CKATs.

Development of a Mobile App for Ecological Momentary Assessment of Circadian Data: Design Considerations and Usability Testing

BACKGROUND

Collecting data on daily habits across a population of individuals is challenging. Mobile-based circadian ecological momentary assessment (cEMA) is a powerful frame for observing the impact of daily living on long-term health.

OBJECTIVE

In this paper, we (1) describe the design, testing, and rationale for specifications of a mobile-based cEMA app to collect timing of eating and sleeping data and (2) compare cEMA and survey data collected as part of a 6-month observational cohort study. The ultimate goal of this paper is to summarize our experience and lessons learned with the Daily24 mobile app and to highlight the pros and cons of this data collection modality.

METHODS

Design specifications for the Daily24 app were drafted by the study team based on the research questions and target audience for the cohort study. The associated backend was optimized to provide real-time data to the study team for participant monitoring and engagement. An external 8-member advisory board was consulted throughout the development process, and additional test users recruited as part of a qualitative study provided feedback through in-depth interviews.

RESULTS

After ≥4 days of at-home use, 37 qualitative study participants provided feedback on the app. The app generally received positive feedback from test users for being fast and easy to use. Test users identified several bugs and areas where modifications were necessary to in-app text and instructions and also provided feedback on the engagement strategy. Data collected through the mobile app captured more variability in eating windows than data collected through a one-time survey, though at a significant cost.

CONCLUSIONS

Researchers should consider the potential uses of a mobile app beyond the initial data collection when deciding whether the time and monetary expenditure are advisable for their situation and goals.

Patient Recruitment Into a Multicenter Clinical Cohort Linking Electronic Health Records From 5 Health Systems: Cross-sectional Analysis

Background

There is growing interest in identifying and recruiting research participants from health systems using electronic health records (EHRs). However, few studies have described the practical aspects of the recruitment process or compared electronic recruitment methods to in-person recruitment, particularly across health systems.

Objective

The objective of this study was to describe the steps and efficiency of the recruitment process and participant characteristics by recruitment strategy.

Methods

EHR-based eligibility criteria included being an adult patient engaged in outpatient primary or bariatric surgery care at one of 5 health systems in the PaTH Clinical Research Network and having ≥2 weight measurements and 1 height measurement recorded in their EHR within the last 5 years. Recruitment strategies varied by site and included one or more of the following methods: (1) in-person recruitment by study staff from clinical sites, (2) US postal mail recruitment letters, (3) secure email, and (4) direct EHR recruitment through secure patient web portals. We used descriptive statistics to evaluate participant characteristics and proportion of patients recruited (ie, efficiency) by modality.

Results

The total number of eligible patients from the 5 health systems was 5,051,187. Of these, 40,048 (0.8%) were invited to enter an EHR-based cohort study and 1085 were enrolled. Recruitment efficiency was highest for in-person recruitment (33.5%), followed by electronic messaging (2.9%), including email (2.9%) and EHR patient portal messages (2.9%). Overall, 779 (65.7%) patients were enrolled through electronic messaging, which also showed greater rates of recruitment of Black patients compared with the other strategies.

Conclusions

We recruited a total of 1085 patients from primary care and bariatric surgery settings using 4 recruitment strategies. The recruitment efficiency was 2.9% for email and EHR patient portals, with the majority of participants recruited electronically. This study can inform the design of future research studies using EHR-based recruitment.

Abstract 017: Meal Intervals And Weight Trajectories In Adults Using The Daily24 Mobile Application: A Prospective Cohort Study

Background: Small pilot and randomized controlled studies suggest that time-restricted feeding may decrease body weight. However, the role of meal timing and intervals, measured using mobile applications, has not been examined in larger population-based studies. The objective of this study is to evaluate the association between meal intervals and weight trajectories among adults from a population-based clinical cohort.

Methods: Multi-site prospective cohort study of adults recruited from three health systems. Over the 6-month study period, 547 participants downloaded and used the Daily24 mobile application to record the timing of meals and sleep for at least one day. Intervals were calculated as the average of all available daily entries for each participant. We obtained information on weight and comorbidities at each outpatient visit from electronic health records available for up to 10 years prior to until 10 months after baseline. We used mixed linear regression to model weight trajectories.

Results: The mean (SD) baseline (at consent) age was 51.1 (15.0) years and body mass index (BMI) 30.8 (7.8) kg/m 2 ; 77.9% were women and 77.5% were White. Average time in the cohort was 5.9 years prior to and 0.3 years after baseline. The mean interval from first to last meal was 11.5 (2.3) hours. The associations between meal intervals and weight trajectories are shown in the Table . The number of meals per day was positively associated with weight change before baseline, and number of snacks and drinks per day was inversely associated with weight change after baseline. Each additional occasion of snacks and drinks was associated with a 3.20 kg weight decrease (95% CI 1.41 to 4.99). None of the other associations were statistically significant.

Conclusions: Number of daily meals was positively associated with weight change in previous periods, while the number of daily snacks and drinks was inversely associated with weight trajectory. The intervals from first to last meal was not associated with weight change.

Preferences for Updates on General Research Results: A Survey of Participants in Genomic Research from Two Institutions

There is a need for multimodal strategies to keep research participants informed about study results. Our aim was to characterize preferences of genomic research participants from two institutions along four dimensions of general research result updates: content, timing, mechanism, and frequency.

METHODS

We conducted a web-based cross-sectional survey that was administered from 25 June 2018 to 5 December 2018.

RESULTS

397 participants completed the survey, most of whom (96%) expressed a desire to receive research updates. Preferences with high endorsement included: update content (brief descriptions of major findings, descriptions of purpose and goals, and educational material); update timing (when the research is completed, when findings are reviewed, when findings are published, and when the study status changes); update mechanism (email with updates, and email newsletter); and update frequency (every three months). Hierarchical cluster analyses based on the four update preferences identified four profiles of participants with similar preference patterns. Very few participants in the largest profile were comfortable with budgeting less money for research activities so that researchers have money to set up services to send research result updates to study participants.

CONCLUSION

Future studies may benefit from exploring preferences for research result updates, as we have in our study. In addition, this work provides evidence of a need for funders to incentivize researchers to communicate results to participants.

Scalable Production of Equine Platelet Lysate for Multipotent Mesenchymal Stromal Cell Culture

Translation of multipotent mesenchymal stromal cell (MSC)-based therapies is advancing in human and veterinary medicine. One critical issue is the in vitro culture of MSC before clinical use. Using fetal bovine serum (FBS) as supplement to the basal medium is still the gold standard for cultivation of many cell types including equine MSC. Alternatives are being explored, with substantial success using platelet lysate-supplemented media for human MSC. However, progress lags behind in the veterinary field. The aim of this study was to establish a scalable protocol for equine platelet lysate (ePL) production and to test the ePL in equine MSC culture. Whole blood was harvested into blood collection bags from 20 healthy horses. After checking sample materials for pathogen contamination, samples from 19 animals were included. Platelet concentrates were prepared using a buffy coat method. Platelets, platelet-derived growth factor BB, and transforming growth factor β1 concentrations were increased in the concentrates compared with whole blood or serum (p < 0.05), while white blood cells were reduced (p < 0.05). The concentrates were lysed using freeze/thaw cycles, which eliminated the cells while growth factor concentrations were maintained. Donor age negatively correlated with platelet and growth factor concentrations after processing (p < 0.05). Finally, all lysates were pooled and the ePL was evaluated as culture medium supplement in comparison with FBS, using adipose-derived MSC from four unrelated donor horses. MSC proliferated well in 10% FBS as well as in 10% ePL. However, using 5 or 2.5% ePL entailed highly inconsistent proliferation or loss of proliferation, with significant differences in generation times and confluencies (p < 0.05). MSC expressed the surface antigens CD90, CD44, and CD29, but CD73 and CD105 detection was low in all culture media. Adipogenic and osteogenic differentiation led to similar results in MSC from different culture media. The buffy coat method is useful to produce equine platelet concentrate with increased platelet and reduced white blood cell content in large scales. The ePL obtained supports MSC expansion similar as FBS when used at the same concentration (10%). Further investigations into equine MSC functionality in culture with ePL should follow.

A method for measuring the effect of certified electronic health record technology on childhood immunization status scores among Medicaid managed care network providers

OBJECTIVE

To provide a methodology for estimating the effect of U.S.-based Certified Electronic Health Records Technology (CEHRT) implemented by primary care physicians (PCPs) on a Healthcare Effectiveness Data and Information Set (HEDIS) measure for childhood immunization delivery.

MATERIALS AND METHODS

This study integrates multiple health care administrative data sources from 2010 through 2014, analyzed through an interrupted time series design and a hierarchical Bayesian model. We compared managed care physicians using CEHRT to propensity-score matched comparisons from network physicians who did not adopt CEHRT. Inclusion criteria for physicians using CEHRT included attesting to the Childhood Immunization Status clinical quality measure in addition to meeting "Meaningful Use" (MU) during calendar year 2013. We used a first-presence patient attribution approach to develop provider-specific immunization scores.

RESULTS

We evaluated 147 providers using CEHRT, with 147 propensity-score matched providers selected from a pool of 1253 PCPs practicing in Maryland. The estimate for change in odds of increasing immunization rates due to CEHRT was 1.2 (95% credible set, 0.88-1.73).

DISCUSSION

We created a method for estimating immunization quality scores using Bayesian modeling. Our approach required linking separate administrative data sets, constructing a propensity-score matched cohort, and using first-presence, claims-based childhood visit information for patient attribution. In the absence of integrated data sets and precise and accurate patient attribution, this is a reusable method for researchers and health system administrators to estimate the impact of health information technology on individual, provider-level, process-based, though outcomes-focused, quality measures.

CONCLUSION

This research has provided evidence for using Bayesian analysis of propensity-score matched provider populations to estimate the impact of CEHRT on outcomes-based quality measures such as childhood immunization delivery.

What influences the "when" of eating and sleeping?A qualitative interview study

Timing of eating relative to sleep and endogenous circadian rhythm impacts weight and cardiometabolic health. We used qualitative methods to explore what influences the "when" of eating and sleeping. We conducted 37 one-on-one semi-structured interviews among participants with a body mass index (BMI) ≥ 25 kg/m² recruited from three internal medicine clinics affiliated with an urban academic hospital. Participants (70.3% Female; 51.4% White; Age range: 21-83 years old) completed measures of social jetlag, physical activity, eating habits, and mobile application use and participated in interviews following a guide developed by the study team. Responses were recorded, transcribed and coded sequentially by two trained researchers using editing-style analysis to identify themes. We identified two main themes, each with subthemes: 1) influences on the "when" of eating and sleeping, with subthemes including social jetlag and being overscheduled, and 2) contextualizing beliefs and perceptions about the "when" of eating and sleeping, with subthemes including perceived recommendations for timing of eating and sleeping, and alignment of behaviors with perceived recommendations. Many participants noted being more flexible in their eating and sleeping times on work-free vs work days. The themes this study identified should be considered when designing interventions that influence the timing of eating and sleeping for weight management.

Are maternal hemodynamic indices markers of fetal growth restriction in pregnancies with a small-for-gestational-age fetus?

OBJECTIVE

Pregnancies complicated by fetal growth restriction (FGR) have a worse outcome than those with a small-for-gestational-age (SGA) fetus. There is increasing evidence of a maternal cardiovascular role in the pathophysiology of FGR. We aimed to compare maternal hemodynamic indices between pregnancies complicated by FGR and those delivering a SGA neonate, using a non-invasive device.

METHODS

This was a prospective study of normotensive pregnancies complicated by FGR (defined as estimated fetal weight (EFW) < 3^rd centile or Doppler evidence of impaired placental-fetal blood flow), those with a SGA fetus (defined as EFW < 10^th centile) and control pregnancies with an appropriately grown fetus. Assessment of maternal hemodynamics (heart rate (HR), cardiac output (CO), mean arterial pressure (MAP), systemic vascular resistance (SVR) and stroke volume) was performed using a non-invasive device (USCOM-1A®). Uterine artery (UtA) pulsatility index (PI) was measured using transabdominal ultrasound. Hemodynamic variables that are affected by gestational age and maternal characteristics were corrected for using device-specific reference ranges. Comparison between groups was performed using the chi-square test or the Mann-Whitney U-test, as appropriate.

RESULTS

A total of 102 FGR, 64 SGA and 401 control pregnancies, with a median gestational age of 36 weeks, were included in the analysis. Women with a pregnancy complicated by FGR and those with a SGA fetus were shorter and weighed less than did controls. Compared with controls, the FGR group had significantly lower median maternal HR (80 beats per min (bpm) vs 85 bpm; P = 0.001) and CO multiples of the median (MoM; 0.91 vs 0.98; P = 0.003), and higher median maternal MAP (90 mmHg vs 87 mmHg; P = 0.040), SVR MoM (1.2 vs 1.0; P < 0.001) and UtA-PI MoM (1.1 vs 0.96; P < 0.001), but there was no significant difference in stroke volume MoM (1.0 vs 0.98; P = 0.647). Compared with the SGA group, the FGR group had a significantly lower median HR (80 bpm vs 87 bpm; P = 0.022), and higher median maternal MAP (90 mmHg vs 85 mmHg; P = 0.025), SVR MoM (1.2 vs 1.0; P = 0.002) and UtA-PI MoM (1.1 vs 0.98; P = 0.005), but there was no significant difference in CO MoM (0.91 vs 0.96; P = 0.092) or stroke volume MoM (1.0 vs 1.0; P = 0.806). There were no significant differences in adjusted maternal hemodynamic indices between the SGA group and controls.

CONCLUSION

Pregnancies complicated by FGR presented with impaired maternal hemodynamic function, as evidenced by lower HR and CO, as well as higher MAP, SVR and UtA resistance. Pregnancies delivering a SGA neonate, without evidence of FGR, had normal maternal hemodynamic function. Maternal hemodynamic indices may therefore be of value in distinguishing FGR from SGA pregnancies. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Evaluation of a Training Program to Improve Organizational Capacity for Health Systems Analytics

OBJECTIVE

The Leadership in Analytics and Data Science (LEADS) course was evaluated for effectiveness. LEADS was a 6-month program for working biomedical and health informatics (BMHI) professionals designed to improve analytics skills, knowledge of enterprise applications, data stewardship, and to foster an analytics community of practice through lectures, hands-on skill building workshops, networking events, and small group projects.

METHODS

The effectiveness of the LEADS course was evaluated using the Kirkpatrick Model by assessing pre- and postcourse knowledge, analytics capabilities, goals, practice, class lecture reaction, and change in the size of participant professional networks. Differences in pre- and postcourse responses were analyzed with a Wilcoxon signed rank test to determine significance, and effect sizes were computed using a z-statistic.

RESULTS

Twenty-nine students completed the course with 96% of respondents reporting that they were "very" or "extremely" likely to recommend the course. Participants reported improvement in several analytics capabilities including Epic data warehousing (p = 0.017), institutional review board policy (p = 0.005), and data stewardship (p = 0.007). Changes in practice patterns mirrored those in self-reported capability. On average, the participant professional network doubled.

CONCLUSION

LEADS was the first course targeted to working BMHI professional at a large academic medical center to have a formal effectiveness evaluation be published in the literature. The course achieved the goals of expansion of BMHI knowledge, skills, and professional networks. The LEADS course provides a template for continuing education of working BMHI professionals.

Please Be Careful with Me: Discrepancies between Adolescent Expectations and Clinician Perspectives on the Management of Pelvic Inflammatory Disease

STUDY OBJECTIVE

To compare clinician perspectives for the treatment of pelvic inflammatory disease (PID) with those of adolescent patients and parents.

DESIGN

Cross-sectional study.

SETTING

Urban academic pediatric and adolescent medicine practices and school-based health clinics in a large urban community with a high prevalence of sexually transmitted infections and a national sample of adolescent-serving clinicians.

PARTICIPANTS

Female patients aged 12-19 years, parents raising an adolescent older than the age of 12 years in the urban community, and clinicians who serve adolescents recruited from regional and national listservs.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Visual analogue scale scores on a scale of 0-10 corresponding to preferences on patient disposition in 17 clinical scenarios for a hypothetical patient with PID.

RESULTS

Compared with adolescents, clinicians were significantly more likely to endorse hospitalizations when patients presented with severe or complicated illness (β = 0.9; standard error [SE], 0.22; P < .001), possible surgical emergency (β = 0.83; SE, 0.2; P < .001), concurrent pregnancy (β = 0.59; SE, 0.3; P = .046), or failure of outpatient treatment (β = 0.58; SE, 0.29; P = .045). Compared with clinicians, adolescents were significantly more likely to endorse hospitalizations when patients presented at a young age (β = 1.36; SE, 0.38; P < .001), were homeless (β = 0.88; SE, 0.32; P = .007), were afraid to inform a partner (β = 1.66; SE, 0.40; P < .001), or had unaware parents (β = 2.86; SE, 0.39; P < .001).

CONCLUSION

Clinicians were more likely to recommend hospitalization when doing so adhered to national guidelines on PID treatment. Adolescents opted for hospitalization more often than clinicians in scenarios in which patients exhibited social vulnerability. Clinicians should engage with adolescents in shared disposition planning and use a more nuanced approach to PID management for adolescents who might not be able to tolerate an outpatient regimen.

Correlation between central and uterine hemodynamics in hypertensive disorders of pregnancy

OBJECTIVE

Pregnancies affected by a hypertensive disorder (HDP) have increased uterine artery pulsatility index (UtA-PI) compared with that in healthy pregnancies. Women with HDP are also known to have lower cardiac output and increased systemic vascular resistance. The aim of this study was to investigate the relationship between central and uterine hemodynamics in HDP and uncomplicated pregnancy.

METHODS

This was a prospective study of HDP and normotensive control singleton pregnancies presenting at a tertiary referral hospital between January 2012 and December 2017. Paired measurements of maternal hemodynamics, using a non-invasive device (USCOM-1A®), and UtA-PI were performed in the third trimester. HDP pregnancies were divided into preterm (onset < 37 weeks' gestation) and term (onset ≥ 37 weeks). Spearman's rank coefficient was used to assess the correlation between the central and uteroplacental hemodynamics. Regression analysis was performed to assess the association of UtA-PI with independent variables.

RESULTS

We included 231 women with HDP (152 with preterm and 79 with term HDP) and 378 controls with normotensive pregnancy. Compared with controls, women with preterm HDP had significantly lower cardiac output (median (interquartile range (IQR)), 6.0 (5.1-7.2) vs 6.6 (5.8-7.5) L/min; P < 0.001) and significantly higher systemic vascular resistance (median (IQR), 1394 (1189-1670) vs 1063 (915-1222) dynes × s/cm⁵ ; P < 0.001) and UtA-PI (median (IQR), 1.0 (0.75-1.4) vs 0.67 (0.58-0.83); P < 0.001). Conversely, in women with term HDP, there were no significant differences in heart rate, cardiac output or UtA-PI compared with controls (all P > 0.05), while systemic vascular resistance was significantly higher (median (IQR), 1315 (1099-1527) vs 1063 (915-1222) dynes × s/cm⁵ ; P < 0.001). On multiple regression analysis, heart rate, mean arterial pressure and stroke volume were associated significantly with mean UtA-PI (all P < 0.001).

CONCLUSIONS

Differences observed between HDP and normotensive pregnancies in third-trimester UtA resistance are mirrored in the central maternal hemodynamic parameters. Late pregnancy differences in the uteroplacental circulation in preterm and term HDP are an index of maternal cardiovascular function rather than being related to inadequate spiral artery remodeling and impaired placentation. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Association of sex and atrial fibrillation therapies with patient-reported outcomes

OBJECTIVES

Women report higher atrial fibrillation (AF) symptom severity and receive less AF therapies than their male counterparts. It is understudied if differences in AF therapies received explains sex differences in AF symptom severity. We investigate the impact of sex and AF therapies on patient-reported outcomes.

METHODS

Participants were recruited (n=953) across four academic medical centres with an AF diagnosis and age ≥18 years. Patient-reported outcomes (AF symptom severity, AF-related quality of life, functional status and emotional status) were determined by biannual surveys. We performed multiple linear regressions on propensity-matched cohorts to determine the association of AF therapies and sex on patient-reported outcomes.

RESULTS

Our study population (n=953) was 65% male (n=616), 93% white (n=890) and 72 (±10) years old. Individuals receiving rate control therapy reported comparatively lower AF-related quality of life (-7.22, 95% CI -11.51 to -2.92) and poorer functional status (-3.69, 95% CI -5.27 to -2.12). Individuals receiving rhythm control strategies did not report significantly different patient-reported outcomes. Women were more likely to report poorer functional status (-2.63, 95% CI -3.86 to -1.40) and poorer AF-related quality of life, higher anxiety (2.33, 95% CI 1.07 to 3.59), higher symptoms of depression (1.48, 95% CI 0.31 to 2.65) and AF symptom severity (0.29, 95% CI 0.07 to 0.52).

CONCLUSIONS

Female sex was associated with comparatively poorer AF symptom severity and quality of life, and this association remained after accounting for AF therapies received. Receiving rate control medication alone was associated with comparatively poorer AF-related quality of life and functional status.

Association of sex, age and education level with patient reported outcomes in atrial fibrillation

BACKGROUND

In atrial fibrillation (AF), there are known sex and sociodemographic disparities in clinical outcomes such as stroke. We investigate whether disparities also exist with respect to patient-reported outcomes. We explored the association of sex, age, and education level with patient-reported outcomes (AF-related quality of life, symptom severity, and emotional and functional status).

METHODS

The PaTH AF cohort study recruited participants (N = 953) with an AF diagnosis and age ≥ 18 years across 4 academic medical centers. We performed longitudinal multiple regression with random effects to determine if individual characteristics were associated with patient-reported outcomes.

RESULTS

Women reported poorer functional status (β - 2.23, 95% CI: -3.52, - 0.94) and AF-related quality of life (β - 4.12, 95% CI: -8.10, - 0.14), and higher symptoms of anxiety (β 2.08, 95% CI: 0.76, 3.40), depression (β 1.44, 95% CI: 0.25, 2.63), and AF (β 0.29, 95% CI: 0.08, 0.50). Individuals < 60 years were significantly (p < 0.05) more likely to report higher symptoms of depression, anxiety, and AF, and poorer AF-related quality of life. Lack of college education was associated with reporting higher symptoms of AF (β 0.42, 95% CI: 0.17, 0.68), anxiety (β 1.86, 95% CI: 0.26, 3.45), and depression (β 1.11, 95% CI: 0.15, 2.38), and lower AF-related quality of life (β - 4.41, 95% CI: -8.25, - 0.57) and functional status.

CONCLUSION

Women, younger adults, and individuals with lower levels of education reported comparatively poor patient-reported outcomes. These findings highlight the importance of understanding why individuals experience AF differently based on certain characteristics.

Anemia Screening, Prevalence, and Treatment in Pediatric Inflammatory Bowel Disease in the United States, 2010-2014

PURPOSE

We examined the prevalence of anemia, annual screening for anemia, and treatment of anemia with iron among children with inflammatory bowel disease (IBD).

METHODS

A retrospective study of U.S. pediatric patients with IBD was performed in the MarketScan commercial claims database from 2010-2014. Children (ages 1-21) with at least two inpatient or outpatient encounters for IBD who had available lab and pharmacy data were included in the cohort. Anemia was defined using World Health Organization criteria. We used logistic regression to determine differences in screening, incident anemia, and treatment based on age at first IBD encounter and sex.

RESULTS

The cohort (n=2,446) included 1,560 Crohn's disease (CD) and 886 ulcerative colitis (UC). Approximately, 85% of CD and 81% of UC were screened for anemia. Among those screened, 51% with CD and 43% with UC had anemia. Only 24% of anemia patients with CD and 20% with UC were tested for iron deficiency; 85% were iron deficient. Intravenous (IV) iron was used to treat 4% of CD and 4% UC patients overall and 8% of those with anemia.

CONCLUSION

At least 80% of children with IBD were screened for anemia, although most did not receive follow-up tests for iron deficiency. The 43%-50% prevalence of anemia was consistent with prior studies. Under-treatment with IV iron points to a potential target for quality improvement.

Value of Genetics-informed Drug Dosing Guidance in Pregnant Women: A Needs Assessment with Obstetric Healthcare Providers at Johns Hopkins

In order to better understand the potential value of genetics-informed drug dose guidance to obstetric healthcare providers at Johns Hopkins we administered a web-based needs assessment survey. The survey included questions about: 1) experience with adjusting drug doses during pregnancy; 2) comfort prescribing medications to pregnant women with chronic conditions; 3) awareness and use of genetics-informed dosing guidance; and 4) perceived value of access to services to provide genetics-informed dosing guidance. Among thirty-one respondents, 81% indicated an interest in access to genetics-informed drug dose guidance, particularly a mobile or electronic health record (EHR) application. It was indicated, however, that genetics is one of many characteristics that influence dose adjustments during pregnancy. This study motivates future research to help obstetric healthcare providers tailor drug dose to individual patients based upon models integrating multiple patient characteristics, including genetics.

The Informatics Stack: A Heuristic Tool for Informatics Teaching

Objective: To develop a heuristic framework for students to organize and apply the many concepts of informatics for rapid use.

Method: Organization of curriculum material and recurrent refinement by student feedback. An Informatics Stack was developed based on several existing informatics and software-development frameworks comprising several levels of abstraction, from what a system is supposed to accomplish (4 levels) to how it accomplishes it (5 levels). At each level, there are specific concerns, types of interoperability, ethical and legal issues, testing and evaluation approaches and methods, and relevant scientific disciplines, and privacy (upper 5 levels), confidentiality (middle 3 levels), and security (lower 4 levels ) concerns whose levels overlap. An 8-week Introduction to Informatics course was taught for 6 years to masters students of informatics and of public health, based on the Stack, with a Final Project continually filled in during the course, where students applied the Stack to existing reports describing health information systems and their deployments.

Results: Student feedback from 538 students working in 116 groups over 6 years shows near-universal appreciation that the Stack helped to organize their review of the report. Each student, from a wide variety of backgrounds, identified some level of the Stack as something they might have otherwise missed, and all levels were invoked by some student. Attributes identified by the students as missing from the Stack concerned the practicalities of system development.

Conclusion: The Stack is a broadly-encompassing heuristic whose application can be learned and applied by students from a wide variety of backgrounds in an 8-week course.

A New Haemoglobin Variant Haemoglobin J Birmingham a 120 (H3) Ala → Glu

An abnormal haemoglobin, which on paper electrophoresis has the mobility of Hb J, has been found in two brothers and, in the heterozygous state at least, is not associated with serious clinical abnormality. The structure of this hitherto unreported haemoglobin is α 120 (H3) Ala → Glu and it is named Haemoglobin J Birmingham.

[Phytovigilance: A medical requirement and a legal obligation]

Phytovigilance consists in supervision of side effects and drug interactions consequential to use of herbal medicinal products, herbal food supplements, herbal cosmetics and/or medicinal plants. It includes thus pharmacovigilance applied to phytotherapy, nutrivigilance and cosmetovigilance but also addictovigilance in case of plants, which lead to drug addiction, and toxicovigilance in case of toxic plants. Becoming necessary owing to (acute or chronic) toxicity risks or to drug interactions risks (of pharmacocinetical or pharmacodynamical kind)--as far as it concerns interactions between several associated plants or between a plant and a chemical or biotechnological allopathic medicine--phytovigilance represents moreover a legal obligation. Pharmacovigilance--in case of herbal medicinal products--is indeed becoming mandatory according to title IX of the European directive 2001/83/EC, whereas nutrivigilance is imposed by the European Food Safety Agency (EFSA).

[Memorandum on sustainable reinforcement of prevention and health promotion: challenges at the federal, state and local level]

Research-based evidence and practice-based experience are core requirements for the effective implementation of preventive interventions. The knowledge gained in the Prevention Research Funding Initiative of the German Federal Ministry of Education and Research (2004-2013) was therefore amalgamated, reflected and consolidated in the Cooperation for Sustainable Prevention Research (KNP) meta-project. In annual strategy meetings, researchers and practitioners from the field and other experts developed 3 memoranda providing recommendations for the further development of research and practice in the field of prevention and health promotion. Memorandum III is primarily aimed at decision-makers in politics and administration at the federal, state and local level, in civil society and in the workplace. Its recommendations show that structuring efforts are urgently needed to achieve sustainable policy, particularly in the fields of health, education, employment and social affairs. Memorandum III brings together the knowledge extracted and problems identified in research projects. More so than its 2 predecessors, Memorandum III abstracts knowledge from the individual projects and attempts to derive guidance for action and decision-making, as shown by the 7 recommendations that appear to useful for consensus-building in practice and research. Value judgments are inevitable. Prevention and health promotion are an investment in the future: of social health, social capital and social peace. Improvement of the framework conditions is needed to achieve the harmonized awareness and the sustained effectiveness of these structure-building efforts in different policy areas, spheres of life, fields of action, and groups of actors. This includes the implementation of an overall national strategy as well as the expansion of sources of funding, extension of the legal framework, overarching coordination, and the establishment of a National Center of Excellence to develop and safeguard prevention and health promotion. The memorandum is intended to stimulate a discourse resulting in structure-building and stabilizing measures designed to ensure the sustainability of prevention and health promotion.

Controlled trial of transfusions for silent cerebral infarcts in sickle cell anemia

BACKGROUND

Silent cerebral infarcts are the most common neurologic injury in children with sickle cell anemia and are associated with the recurrence of an infarct (stroke or silent cerebral infarct). We tested the hypothesis that the incidence of the recurrence of an infarct would be lower among children who underwent regular blood-transfusion therapy than among those who received standard care.

METHODS

In this randomized, single-blind clinical trial, we randomly assigned children with sickle cell anemia to receive regular blood transfusions (transfusion group) or standard care (observation group). Participants were between 5 and 15 years of age, with no history of stroke and with one or more silent cerebral infarcts on magnetic resonance imaging and a neurologic examination showing no abnormalities corresponding to these lesions. The primary end point was the recurrence of an infarct, defined as a stroke or a new or enlarged silent cerebral infarct.

RESULTS

A total of 196 children (mean age, 10 years) were randomly assigned to the observation or transfusion group and were followed for a median of 3 years. In the transfusion group, 6 of 99 children (6%) had an end-point event (1 had a stroke, and 5 had new or enlarged silent cerebral infarcts). In the observation group, 14 of 97 children (14%) had an end-point event (7 had strokes, and 7 had new or enlarged silent cerebral infarcts). The incidence of the primary end point in the transfusion and observation groups was 2.0 and 4.8 events, respectively, per 100 years at risk, corresponding to an incidence rate ratio of 0.41 (95% confidence interval, 0.12 to 0.99; P=0.04).

CONCLUSIONS

Regular blood-transfusion therapy significantly reduced the incidence of the recurrence of cerebral infarct in children with sickle cell anemia. (Funded by the National Institute of Neurological Disorders and Stroke and others; Silent Cerebral Infarct Multi-Center Clinical Trial ClinicalTrials.gov number, NCT00072761, and Current Controlled Trials number, ISRCTN52713285.).

PaTH: towards a learning health system in the Mid-Atlantic region

The PaTH (University of Pittsburgh/UPMC, Penn State College of Medicine, Temple University Hospital, and Johns Hopkins University) clinical data research network initiative is a collaborative effort among four academic health centers in the Mid-Atlantic region. PaTH will provide robust infrastructure to conduct research, explore clinical outcomes, link with biospecimens, and improve methods for sharing and analyzing data across our diverse populations. Our disease foci are idiopathic pulmonary fibrosis, atrial fibrillation, and obesity. The four network sites have extensive experience in using data from electronic health records and have devised robust methods for patient outreach and recruitment. The network will adopt best practices by using the open-source data-sharing tool, Informatics for Integrating Biology and the Bedside (i2b2), at each site to enhance data sharing using centrally defined common data elements, and will use the Shared Health Research Information Network (SHRINE) for distributed queries across the network.

Elektronenrückstreuraten leichter Elemente in Molièrescher Näherung / Electron Backscattering Rates of Light Elements in Molière Approximation

Electron backscattering rates of light elements (atomic number Z = 6, 13, 29) are evaluated for electron energies of E = 20···60 keV. The scattering amplitude in Moliere approximation is expanded as a series. The series elements are calculated in closed form with the aid of substitute functions. By comparison with the first Born approximation this yields correction factors of 1···1,25.

Der Gültigkeitsbereich der Molièreschen Näherung/ The Range of Validity of the Molière Approximation

The Moliere approximation of the scattering amplitude is, following earlier statements, a high-energy and small-angle approximation. Recent investigations show that there is no intrinsic small-angle restriction, the restriction being due to special derivations. A method is given, to obtain the scattering amplitude in the Moliere approximation without small-angle assumption. This enables to evaluate electron backscattering rates with the aid of the Moliere scattering amplitude.

Recommendations for the use of operational electronic health record data in comparative effectiveness research

There is an increasing amount of clinical data in operational electronic health record (EHR) systems. Such data provide substantial opportunities for their re-use for many purposes, including comparative effectiveness research (CER). In a previous paper, we identified a number of caveats related to the use of such data, noting that they may be inaccurate, incomplete, transformed in ways that undermine their meaning, unrecoverable for research, of unknown provenance, of insufficient granularity, or incompatible with research protocols. In this paper, we provide recommendations for overcoming these caveats with the goal of leveraging such data to benefit CER and other health care activities. These recommendations include adaptation of “best evidence” approaches to use of data; processes to evaluate availability, completeness, quality, and transformability of data; creation of tools to manage data and their attributes; determination of metrics for assessing whether data are “research grade”; development of methods for comparative validation of data; construction of a methodology database for methods involving use of clinical data; standardized reporting methods for data and their attributes; appropriate use of informatics expertise; and a research agenda to determine biases inherent in operational data and to assess informatics approaches to their improvement.

Copy number variation prevalence in known asthma genes and their impact on asthma susceptibility

BACKGROUND

Genetic studies have identified numerous genes reproducibly associated with asthma, yet these studies have focussed almost entirely on single nucleotide polymorphisms (SNPs), and virtually ignored another highly prevalent form of genetic variation: Copy Number Variants (CNVs).

OBJECTIVE

To survey the prevalence of CNVs in genes previously associated with asthma, and to assess whether CNVs represent the functional asthma-susceptibility variants at these loci.

METHODS

We genotyped 383 asthmatic trios participating in the Childhood Asthma Management Program (CAMP) using a competitive genomic hybridization (CGH) array designed to interrogate 20 092 CNVs. To ensure comprehensive assessment of all potential asthma candidate genes, we purposely used liberal asthma gene inclusion criteria, resulting in consideration of 270 candidate genes previously implicated in asthma. We performed statistical testing using FBAT-CNV.

RESULTS

Copy number variation in asthma candidate genes was prevalent, with 21% of tested genes residing near or within one of 69 CNVs. In six instances, the complete candidate gene sequence resides within the CNV boundaries. On average, asthmatic probands carried six asthma-candidate CNVs (range 1-29). However, the vast majority of identified CNVs were of rare frequency (< 5%) and were not statistically associated with asthma. Modest evidence for association with asthma was observed for 2 CNVs near NOS1 and SERPINA3. Linkage disequilibrium analysis suggests that CNV effects are unlikely to explain previously detected SNP associations with asthma.

CONCLUSIONS AND CLINICAL RELEVANCE

Although a substantial proportion of asthma-susceptibility genes harbour polymorphic CNVs, the majority of these variants do not confer increased asthma risk. The lack of linkage disequilibrium (LD) between CNVs and asthma-associated SNPs suggests that these CNVs are unlikely to represent the functional variant responsible for most known asthma associations.