SARS-CoV-2 RNA and nucleocapsid antigen are blood biomarkers associated with severe disease outcomes that improve in response to remdesivir.

BACKGROUND: Although antivirals remain important for the treatment COVID-19, methods to assess treatment efficacy are lacking. Here, we investigated the impact of remdesivir on viral dynamics and their contribution to understanding antiviral efficacy in the multicenter ACTT-1 clinical trial that randomized patients to remdesivir or placebo. METHODS: Longitudinal specimens collected during hospitalization from a substudy of 642 COVID-19 patients were measured for viral RNA (upper respiratory tract and plasma), viral nucleocapsid antigen (serum), and host immunologic markers. Associations with clinical outcomes and response to therapy were assessed. RESULTS: Higher baseline plasma viral loads were associated with poorer clinical outcomes, and decreases in viral RNA and antigen in blood but not the upper respiratory tract correlated with enhanced benefit from remdesivir. The treatment effect of remdesivir was most pronounced in patients with elevated baseline nucleocapsid antigen levels: the recovery rate ratio was 1.95 (95%CI 1.40-2.71) for levels >245 pg/ml vs 1.04 (95%CI 0.76-1.42) for levels < 245 pg/ml. Remdesivir also accelerated the rate of viral RNA and antigen clearance in blood, and patients whose blood levels decreased were more likely to recover and survive. CONCLUSIONS: Reductions in SARS-CoV-2 RNA and antigen levels in blood correlated with clinical benefit from antiviral therapy.

Development of a Common Data Model for a Multisite and Multiyear Study of Virtual Visit Implementation: A Case Study.

BACKGROUND/OBJECTIVE: In multisite studies, a common data model (CDM) standardizes dataset organization, variable definitions, and variable code structures and can support distributed data processing. We describe the development of a CDM for a study of virtual visit implementation in 3 Kaiser Permanente (KP) regions. METHODS: We conducted several scoping reviews to inform our study's CDM design: (1) virtual visit mode, implementation timing, and scope (targeted clinical conditions and departments); and (2) extant sources of electronic health record data to specify study measures. Our study covered the period from 2017 through June 2021. Integrity of the CDM was assessed by a chart review of random samples of virtual and in-person visits, overall and by specific conditions of interest (neck or back pain, urinary tract infection, major depression). RESULTS: The scoping reviews identified a need to address differences in virtual visit programs across the 3 KP regionsto harmonize measurement specifications for our research analyses. The final CDM contained patient-level, provider-level, and system-level measures on 7,476,604 person-years for KP members aged 19 years and above. Utilization included 2,966,112 virtual visits (synchronous chats, telephone visits, video visits) and 10,004,195 in-person visits. Chart review indicated the CDM correctly identified visit mode on>96% (n=444) of visits, and presenting diagnosis on >91% (n=482) of visits. CONCLUSIONS: Upfront design and implementation of CDMs may be resource intensive. Once implemented, CDMs, like the one we developed for our study, provide downstream programming and analytic efficiencies by harmonizing, in a consistent framework, otherwise idiosyncratic temporal and study site differences in source data.

Temporal Improvements in COVID-19 Outcomes for Hospitalized Adults: A Post Hoc Observational Study of Remdesivir Group Participants in the Adaptive COVID-19 Treatment Trial.

BACKGROUND: The COVID-19 standard of care (SOC) evolved rapidly during 2020 and 2021, but its cumulative effect over time is unclear. OBJECTIVE: To evaluate whether recovery and mortality improved as SOC evolved, using data from ACTT (Adaptive COVID-19 Treatment Trial). DESIGN: ACTT is a series of phase 3, randomized, double-blind, placebo-controlled trials that evaluated COVID-19 therapeutics from February 2020 through May 2021. ACTT-1 compared remdesivir plus SOC to placebo plus SOC, and in ACTT-2 and ACTT-3, remdesivir plus SOC was the control group. This post hoc analysis compared recovery and mortality between these comparable sequential cohorts of patients who received remdesivir plus SOC, adjusting for baseline characteristics with propensity score weighting. The analysis was repeated for participants in ACTT-3 and ACTT-4 who received remdesivir plus dexamethasone plus SOC. Trends in SOC that could explain outcome improvements were analyzed. (ClinicalTrials.gov: NCT04280705 [ACTT-1], NCT04401579 [ACTT-2], NCT04492475 [ACTT-3], and NCT04640168 [ACTT-4]). SETTING: 94 hospitals in 10 countries (86% U.S. participants). PARTICIPANTS: Adults hospitalized with COVID-19. INTERVENTION: SOC. MEASUREMENTS: 28-day mortality and recovery. RESULTS: Although outcomes were better in ACTT-2 than in ACTT-1, adjusted hazard ratios (HRs) were close to 1 (HR for recovery, 1.04 [95% CI, 0.92 to 1.17]; HR for mortality, 0.90 [CI, 0.56 to 1.40]). Comparable patients were less likely to be intubated in ACTT-2 than in ACTT-1 (odds ratio, 0.75 [CI, 0.53 to 0.97]), and hydroxychloroquine use decreased. Outcomes improved from ACTT-2 to ACTT-3 (HR for recovery, 1.43 [CI, 1.24 to 1.64]; HR for mortality, 0.45 [CI, 0.21 to 0.97]). Potential explanatory factors (SOC trends, case surges, and variant trends) were similar between ACTT-2 and ACTT-3, except for increased dexamethasone use (11% to 77%). Outcomes were similar in ACTT-3 and ACTT-4. Antibiotic use decreased gradually across all stages. LIMITATION: Unmeasured confounding. CONCLUSION: Changes in patient composition explained improved outcomes from ACTT-1 to ACTT-2 but not from ACTT-2 to ACTT-3, suggesting improved SOC. These results support excluding nonconcurrent controls from analysis of platform trials in rapidly changing therapeutic areas. PRIMARY FUNDING SOURCE: National Institute of Allergy and Infectious Diseases.

Design of an observational multi-country cohort study to assess immunogenicity of multiple vaccine platforms (InVITE).

In response to the COVID-19 pandemic, COVID-19 vaccines have been developed, and the World Health Oraganization (WHO) has granted emergency use listing to multiple vaccines. Studies of vaccine immunogenicity data from implementing COVID-19 vaccines by national immunization programs in single studies spanning multiple countries and continents are limited but critically needed to answer public health questions on vaccines, such as comparing immune responses to different vaccines and among different populations.

Longitudinal assessment of liver stiffness by transient elastography for chronic hepatitis C patients.

BACKGROUND: Liver fibrosis is a common pathway of liver injury and is a feature of most chronic liver diseases. Fibrosis progression varies markedly in patients with hepatitis C virus (HCV). Liver stiffness has been recommended as a parameter of fibrosis progression/regression in patients with HCV. AIM: To investigate changes in liver stiffness measured by transient elastography (TE) in a large, racially diverse cohort of United States patients with chronic hepatitis C (CHC). METHODS: We evaluated the differences in liver stiffness between patients treated with direct-acting antiviral (DAA) therapy and untreated patients. Patients had ≥ 2 TE measurements and no prior DAA exposure. We used linear regression to measure the change in liver stiffness between first and last TE in response to treatment, controlling for age, sex, race, diabetes, smoking status, human immunodeficiency virus status, baseline alanine aminotransferase, and baseline liver stiffness. Separate regression models analyzed the change in liver stiffness as measured by kPa, stratified by cirrhosis status. RESULTS: Of 813 patients, 419 (52%) initiated DAA treatment. Baseline liver stiffness was 12 kPa in 127 (16%). Median time between first and last TE was 11.7 and 12.7 mo among treated and untreated patients, respectively. There was no significant change in liver stiffness observed over time in either the group initiating DAA treatment (0.016 kPa/month; CI: -0.051, 0.084) or in the untreated group (0.001 kPa/mo; CI: -0.090, 0.092), controlling for covariates. A higher baseline kPa score was independently associated with decreased liver stiffness. CONCLUSION: DAA treatment was not associated with a differential change in liver stiffness over time in patients with CHC compared to untreated patients.

Early Referral, Living Donation, and Preemptive Kidney Transplant.

BACKGROUND: Preemptive kidney transplant (PKT) is recognized as the most beneficial and cost-effective form of renal replacement therapy among patients with end-stage renal disease. Despite optimal outcomes and improved quality of life associated with PKT, its use as a first renal replacement therapy remains low among patients with end-stage renal disease. The goal of this retrospective cohort study was to compare, among adult kidney transplant recipients, characteristics across PKT status. METHODS: We compared the characteristics of patients who did and did not have a PKT over 5 years, from 2010 to 2014, using the electronic health records of Kaiser Permanente Mid-Atlantic States. RESULTS: A total of 233 patients received a kidney-alone transplant, and, of these, 44 patients (19%) were PKT and 189 patients (81%) were non-PKT. Of the patients in the PKT group, 43% received a kidney from a deceased donor. PKT recipients were more often White, had polycystic kidney disease or glomerulonephritis, received a living donor organ, and were transplanted at certain transplant centers. Estimated glomerular filtration rate on listing for those who received a deceased donor transplant was higher in PKT than non-PKT patients listed pre-dialysis. CONCLUSIONS: PKT was associated with having a living kidney donor and with having a higher estimated glomerular filtration rate at listing for deceased donor recipients.

A Comprehensive Coordinator Supported Hepatitis C Virus Testing and Linkage to Treatment Program at Kaiser Permanente Mid-Atlantic States.

Since 2020, the US Preventive Services Taskforce has recommended expanding hepatitis C virus (HCV) screening to include ages 18-79, in addition to baby boomers (born 1945-1965) and those at-risk for hepatitis C virus. This retrospective cohort analysis compared patients (18 years and above) tested for HCV through usual care versus a coordinator-supported program (HCV pathway) during 2015-2018 within Kaiser Permanente Mid-Atlantic States (KPMAS). In total, 131,176 patients were tested through the HCV pathway and 128,311 through usual care (non-standardized testing). Of those tested, 1.6% (HCV pathway) and 0.5% (usual care) had chronic HCV. Of those with chronic HCV, more patients tested within the HCV pathway completed hepatic transient elastography (82.6% HCV pathway vs. 45.6% usual care; p < 0.001) and a gastroenterology visit (72.2% HCV pathway vs. 46.5% usual care; p < 0.001), and had filled prescriptions for treatment (56.5% HCV pathway vs. 40.3% usual care; p < 0.001). The median time to complete each step was shorter for those tested through the HCV pathway (hepatic transient elastography (26 vs. 118 days), gastroenterology visit (63 vs. 131 days), and prescription fill (222 vs. 326 days)). More patients tested through a coordinator-supported, standardized testing pathway completed the necessary testing steps, in less time, compared to usual care. These findings may inform institutions seeking to create effective population-wide testing programs for HCV and other conditions.

Rate of sepsis hospitalizations after misdiagnosis in adult emergency department patients: a look-forward analysis with administrative claims data using Symptom-Disease Pair Analysis of Diagnostic Error (SPADE) methodology in an integrated health system.

OBJECTIVES: Delays in sepsis diagnosis can increase morbidity and mortality. Previously, we performed a Symptom-Disease Pair Analysis of Diagnostic Error (SPADE) "look-back" analysis to identify symptoms at risk for delayed sepsis diagnosis. We found treat-and-release emergency department (ED) encounters for fluid and electrolyte disorders (FED) and altered mental status (AMS) were associated with downstream sepsis hospitalizations. In this "look-forward" analysis, we measure the potential misdiagnosis-related harm rate for sepsis among patients with these symptoms. METHODS: Retrospective cohort study using electronic health record and claims data from Kaiser Permanente Mid-Atlantic States (2013-2018). Patients ≥18 years with ≥1 treat-and-release ED encounter for FED or AMS were included. Observed greater than expected sepsis hospitalizations within 30 days of ED treat-and-release encounters were considered potential misdiagnosis-related harms. Temporal analyses were employed to differentiate case and comparison (superficial injury/contusion ED encounters) cohorts. RESULTS: There were 4,549 treat-and-release ED encounters for FED or AMS, 26 associated with a sepsis hospitalization in the next 30 days. The observed (0.57%) minus expected (0.13%) harm rate was 0.44% (absolute) and 4.5-fold increased over expected (relative). There was a spike in sepsis hospitalizations in the week following FED/AMS ED visits. There were fewer sepsis hospitalizations and no spike in admissions in the week following superficial injury/contusion ED visits. Potentially misdiagnosed patients were older and more medically complex. CONCLUSIONS: Potential misdiagnosis-related harms from sepsis are infrequent but measurable using SPADE. This look-forward analysis validated our previous look-back study, demonstrating the SPADE approach can be used to study infectious disease syndromes.

Antecedent treat-and-release diagnoses prior to sepsis hospitalization among adult emergency department patients: a look-back analysis employing insurance claims data using Symptom-Disease Pair Analysis of Diagnostic Error (SPADE) methodology.

OBJECTIVES: The aim of this study was to identify delays in early pre-sepsis diagnosis in emergency departments (ED) using the Symptom-Disease Pair Analysis of Diagnostic Error (SPADE) approach. METHODS: SPADE methodology was employed using electronic health record and claims data from Kaiser Permanente Mid-Atlantic States (KPMAS). Study cohort included KPMAS members ≥18 years with ≥1 sepsis hospitalization 1/1/2013-12/31/2018. A look-back analysis identified treat-and-release ED visits in the month prior to sepsis hospitalizations. Top 20 diagnoses associated with these ED visits were identified; two diagnosis categories were distinguished as being linked to downstream sepsis hospitalizations. Observed-to-expected (O:E) and temporal analyses were performed to validate the symptom selection; results were contrasted to a comparison group. Demographics of patients that did and did not experience sepsis misdiagnosis were compared. RESULTS: There were 3,468 sepsis hospitalizations during the study period and 766 treat-and-release ED visits in the month prior to hospitalization. Patients discharged from the ED with fluid and electrolyte disorders (FED) and altered mental status (AMS) were most likely to have downstream sepsis hospitalizations (O:E ratios of 2.66 and 2.82, respectively). Temporal analyses revealed that these symptoms were overrepresented and temporally clustered close to the hospitalization date. Approximately 2% of sepsis hospitalizations were associated with prior FED or AMS ED visits. CONCLUSIONS: Treat-and-release ED encounters for FED and AMS may represent harbingers for downstream sepsis hospitalizations. The SPADE approach can be used to develop performance measures that identify pre-sepsis.

Life Expectancy Trends Among Integrated Health Care System Enrollees, 2014-2017.

INTRODUCTION: The Centers for Disease Control and Prevention (CDC) has reported downward trends in life expectancy and racial/ethnic differences between 2014 and 2017. OBJECTIVE: To determine the life expectancy of the Kaiser Permanente Mid-Atlantic States (KPMAS) insured population as compared to the CDC National Vital Statistics data from 2014 to 2017. We also aimed to highlight the utilization of membership data to inform population statistical estimates such as life expectancy. We examine whether national trends in life expectancy are reflected in an insured population with relatively uniform access to care. METHODS: This retrospective, data only study examined life expectancy between 2014 and 2017. Data from electronic medical records and the National Death Index were combined to construct complete life tables by race and sex for the KPMAS population, which was compared to the CDC National Vital Statistics data. RESULTS: From 2014 to 2017, the overall KPMAS population life expectancy at birth varied between 84.6 and 85.2 years compared to the CDC reported national average of 78.6-78.9 years (p < 0.001). While the CDC dataset reported a 3.5- to 3.7-year life expectancy gap between non-Hispanic White and non-Hispanic Black populations, in the KPMAS population, this gap was significantly smaller (0.0-0.9 years). The gap in life expectancy between males and females was consistent across KPMAS and the CDC data; however, overall KPMAS male and female patient life expectancy was extended in comparison. CONCLUSION: Among members who disclosed their race/ethnicity, KPMAS Hispanic, non-Hispanic Black, and non-Hispanic White members had significantly higher life expectancies than the CDC dataset in all years reported.

Hepatitis C Care Pathway Associated With Increased Screening, Confirmation, and Diagnosis Communication to Patients.

National policy initiatives1-3 and the advent of highly efficacious direct-acting antivirals4 set the stage to increase the identification and care of patients with hepatitis C virus (HCV). We implemented a multifaceted HCV care pathway, inclusive of automated screening alerts for all patients born between 1945 and 1965 as they are registered for appointments, reflex laboratory orders for positive HCV antibody results, and a care coordinator to facilitate diagnosis communication and engagement in follow-up care.5 We report the impact of that pathway on HCV screening, confirmation, diagnosis communication, and co-infection screening.

Beyond the HIV Care Continuum and Viral Suppression: Broadening the Scope of Quality Metrics for Total HIV Patient Care.

Assessing quality care for people with HIV (PWH) should not be limited to reporting on HIV Care Continuum benchmarks, particularly viral suppression rates. At Kaiser Permanente Mid-Atlantic States (KPMAS), an integrated health system providing HIV care in the District of Columbia, Maryland, and Virginia, we created a comprehensive measure of HIV quality care, including both preventative measures and clinical outcomes. We included PWH ≥18 years old with ≥6 months KPMAS membership between 2015 and 2018. Process quality metrics (QMs) include: pneumococcal vaccination and influenza vaccination; primary care physician (PCP) and/or HIV/infectious disease (HIV/ID) visits with additional HIV/ID visit; antiretroviral treatment medication fills; and syphilis and gonorrhea/chlamydia screenings. Outcome QMs include HIV RNA <200/mL and other measurements within normal range [blood pressure, body mass index (BMI), hemoglobin, blood sugar, alanine transaminase, low-density lipoproteins, estimated glomerular filtration rate]; no hospitalization/emergency department visit; no new depression diagnosis; remaining or becoming a nonsmoker. Logistic models estimated odds of achieving QMs associated with sex, age, race/ethnicity, insurance type, and HIV risk. A total of 4996 observations were analyzed. 45.6% met all process QMs, while 19.6% met all outcome QMs. Least frequently met process QM was PCP or HIV/ID visit (74.5%); least met outcome QM was BMI (60.2%). Significantly lower odds of achieving all QMs among women {odds ratio (OR) = 0.63 [95% confidence interval (CI): 0.49-0.81]} and those with Medicaid and Medicare [vs. commercial; OR = 0.48 (95% CI: 0.30-0.76) and 0.47 (95% CI: 0.31-0.71)]. Broadening the scope of HIV patient care QMs beyond viral suppression helps identify opportunities for improvement. Successful process metrics do not necessarily coincide with greater outcome metrics.

Factors contributing to racial disparities in influenza vaccinations.

BACKGROUND: Racial/ethnic disparities in rates of influenza vaccinations in the US remain an issue even among those with access, no out-of-pocket costs, and after adjusting for confounders. We used an approach called the Oaxaca-Blinder (OB) decomposition method to ascertain the contribution of covariates individually and in aggregate to the racial disparity in influenza vaccination. METHODS: We included members > = 18 years of age as of 05/01/2014 with continuous enrollment through 04/30/2015. Influenza vaccination was defined by diagnosis, procedure, or medication codes, or documentation in the immunization table. Characteristics were reported by race. Logistic regression models estimated the odds of vaccination associated with: (1) race; and (2) covariates stratified by race. The Oaxaca-Blinder (OB) method calculated the contribution of covariates to the difference or disparity in vaccination between Blacks and Whites. RESULTS: We found that among adults, 44% were vaccinated; 55% were Black; and 45% were White. Black members have 42% lower odds of vaccination than White members. The contribution of the differences in the average value of the study covariates between Black and White members (the OB covariate effect) accounted for 29% of the racial disparity. The contributions to the total White-Black disparity in vaccination included: age (16%), neighborhood median income (11%), and registration on the online patient portal (13%). The contribution of the differences in how the covariates impact vaccination (OB coefficient effect) accounted for 71% of the disparity in vaccination between Blacks and Whites. CONCLUSION: In conclusion, equalizing average covariate values in Blacks and Whites could reduce the racial disparity in influenza vaccination by 29%. For health system vaccine campaigns, improving registration on the patient portal may be a target component of an effective system-level strategy to reduce racial disparities in vaccination. Additional information on patient-centered factors could further improve the value of the OB approach.

Impact of Alternative Encounter Types on HIV Viral Suppression Rates in an Integrated Health System.

Kaiser Permanente Mid-Atlantic States (KPMAS) members are increasingly utilizing electronic encounter types, such as telephone appointments and secure messaging for healthcare purposes, although their impact on health outcomes is unknown. We evaluated whether use of alternative encounters by adult human immunodeficiency virus (HIV)-infected patients affected the likelihood of achieving viral suppression (VS). Our study population of 3114 patients contributed 6520 patient-years between 2014 and 2016. We compared VS (HIV RNA <200 copies/mL) by number of in-person visits (1 or ≥2), with further stratification for additional phone and/or e-mail encounters (none, phone only, e-mail only, and both phone and e-mail). Rate ratios (RRs) for VS by number of in-person visits and encounter types were obtained from Poisson modeling, adjusting for age, sex, race/ethnicity, and HIV risk. Compared to those with ≥2 visits, patients with one in-person visit alone were significantly less likely to achieve VS (RR = 0.93; 95% confidence interval, CI: [0.87-1.00]), as were those with one in-person visit plus a telephone encounter (0.93; [0.90-0.97]). We did not find significant differences in VS comparing patients with one in-person visit plus e-mail only (RR = 1.00; 95% CI: [0.97-1.02]) or plus e-mail and telephone (0.99; [0.97-1.01]) to those with ≥2 in-person visits. If supplemented by e-mail communications (with or without telephone contact), patients with one in-person visit per year had similar estimated rates of VS compared with ≥2 in-person visits. More research is needed to know if these findings apply to other care systems.

Kidney Function Decline in Patients with CKD and Untreated Hepatitis C Infection.

BACKGROUND AND OBJECTIVES: Studies evaluating the role of hepatitis C viral (HCV) infection on the progression of CKD are few and conflicting. Therefore, we evaluated the association of untreated HCV on kidney function decline in patients with stage 3-5 CKD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This retrospective cohort study included members of Kaiser Permanente Southern California and Kaiser Permanente Mid-Atlantic States aged ≥18 years, with incident HCV and CKD diagnoses from January 1, 2004 to December 31, 2014. We used generalized estimating equations to compare the rate of change in eGFR between those with HCV and CKD versus CKD alone, adjusting for covariates. Cox proportional hazards models compared the risk of 25% decrease in eGFR and ESKD (defined as progression to eGFR<15 ml/min per 1.73 m2 on two or more occasions, at least 90 days apart) in those with HCV and CKD versus CKD alone, adjusting for covariates. RESULTS: We identified 151,974 patients with CKD only and 1603 patients with HCV and CKD who met the study criteria. The adjusted annual decline of eGFR among patients with HCV and CKD was greater by 0.58 (95% confidence interval [95% CI], 0.31 to 0.84) ml/min per 1.73 m2, compared with that in the CKD-only population (HCV and CKD, -1.61; 95% CI, -1.87 to -1.35 ml/min; CKD only, -1.04; 95% CI, -1.06 to -1.01 ml/min). Adjusted for covariates, the hazard for a 25% decline in eGFR and for ESKD were 1.87 (95% CI, 1.75 to 2.00) and 1.93 (95% CI, 1.64 to 2.27) times higher among those with HCV and CKD, respectively, compared with those with CKD only. CONCLUSIONS: Untreated HCV infection was associated with greater kidney function decline in patients with stage 3-5 CKD.

Increasing hepatitis C screening in a large integrated health system: science and policy in concert.

OBJECTIVES: To evaluate whether the updated 2013 US Preventive Services Task Force (USPSTF) hepatitis C virus (HCV) screening recommendations, related Affordable Care Act provisions, and the impending availability of efficacious therapies were associated with increased screening in an integrated health system. STUDY DESIGN: We analyzed 665,339 records of adult patients visiting Kaiser Permanente Mid-Atlantic States clinics from 2003 to 2014. METHODS: We used Cox proportional hazards to estimate time to HCV screening and confirmation after June 1, 2013, compared with prior. RESULTS: HCV screening steadily increased over time, but it jumped 29% (P <.01) from 2013 to 2014 versus 4% (P <.01) from 2012 to 2013. The adjusted hazard ratio for HCV screening since June 2013 was 2.40 (95% CI, 2.34-2.47) times higher than it was pre-intervention among the birth cohort (those born 1945-1965) and 2.00 (95% CI, 1.96-2.04) times higher in those born in other years, representing a 1.20-fold (95% CI, 1.17-1.24) greater increase in the screening rate among the birth cohort. We also identified variability in those thought to be at higher risk of HCV infection. CONCLUSIONS: HCV screening has been increasing in our healthcare system, more so since June 2013 and among the birth cohort. The availability of efficacious therapies and coverage policies coincident with the USPSTF recommendations may have facilitated access to screening and treatment in ways that were absent at the time of the 2012 CDC recommendations. Health systems must also be poised to make resources available to clinicians and patients in order to incentivize screening. Future research should inform a better understanding of incentives and barriers to screening and linkage to care from all stakeholder perspectives.

Genome scan for cognitive trait loci of dyslexia: Rapid naming and rapid switching of letters, numbers, and colors.

Dyslexia, or specific reading disability, is a common developmental disorder that affects 5-12% of school-aged children. Dyslexia and its component phenotypes, assessed categorically or quantitatively, have complex genetic bases. The ability to rapidly name letters, numbers, and colors from rows presented visually correlates strongly with reading in multiple languages and is a valid predictor of reading and spelling impairment. Performance on measures of rapid naming and switching, RAN and RAS, is stable throughout elementary school years, with slowed performance persisting in adults who still manifest dyslexia. Targeted analyses of dyslexia candidate regions have included RAN measures, but only one other genome-wide linkage study has been reported. As part of a broad effort to identify genetic contributors to dyslexia, we performed combined oligogenic segregation and linkage analyses of measures of RAN and RAS in a family-based cohort ascertained through probands with dyslexia. We obtained strong evidence for linkage of RAN letters to the DYX3 locus on chromosome 2p and RAN colors to chromosome 10q, but were unable to confirm the chromosome 6p21 linkage detected for a composite measure of RAN colors and objects in the previous genome-wide study.

Genome scan for spelling deficits: effects of verbal IQ on models of transmission and trait gene localization.

Dyslexia is a complex learning disability with evidence for a genetic basis. Strategies that may be useful for dissecting its genetic basis include the study of component phenotypes, which may simplify the underlying genetic complexity, and use of an analytic approach that accounts for the multilocus nature of the trait to guide the investigation and increase power to detect individual loci. Here we present results of a genetic analysis of spelling disability as a component phenotype. Spelling disability is informative in analysis of extended pedigrees because it persists into adulthood. We show that a small number of hypothesized loci are sufficient to explain the inheritance of the trait in our sample, and that each of these loci maps to one of four genomic regions. Individual trait models and locations are a function of whether a verbal IQ adjustment is included, suggesting mediation through both IQ-related and unrelated pathways.