A Bayesian zero-inflated beta-binomial model for longitudinal data with group-specific changepoints

Timeline followback (TLFB) is often used in addiction research to monitor recent substance use, such as the number of abstinent days in the past week. TLFB data usually take the form of binomial counts that exhibit overdispersion and zero inflation. Motivated by a 12-week randomized trial evaluating the efficacy of varenicline tartrate for smoking cessation among adolescents, we propose a Bayesian zero-inflated beta-binomial model for the analysis of longitudinal, bounded TLFB data. The model comprises a mixture of a point mass that accounts for zero inflation and a beta-binomial distribution for the number of days abstinent in the past week. Because treatment effects appear to level off during the study, we introduce random changepoints for each study group to reflect group-specific changes in treatment efficacy over time. The model also includes fixed and random effects that capture group- and subject-level slopes before and after the changepoints. Using the model, we can accurately estimate the mean trend for each study group, test whether the groups experience changepoints simultaneously, and identify critical windows of treatment efficacy. For posterior computation, we propose an efficient Markov chain Monte Carlo algorithm that relies on easily sampled Gibbs and Metropolis-Hastings steps. Our application shows that the varenicline group has a short-term positive effect on abstinence that tapers off after week 9.

Cannabis Use Disorder in Adolescents

With increasing cannabis potency, increasing variety of methods of cannabis use, and lower perceived risk of cannabis use, it is increasingly important clinicians who work with adolescents remain up-to-date on the latest literature regarding cannabis use and its associated outcomes. Adolescent cannabis use is associated with chronic cognitive, psychosocial, psychiatric, and physical outcomes. Clinicians working in this field should be able to recognize cannabis use disorder, understand how adolescent cannabis use can impact the developing mind, and have informed discussions with patients and families regarding risks of use.

Outcomes of Sepsis in Patients With and Without HIV Infection: A Retrospective Study

BACKGROUND

HIV infection is associated with increased infections.

OBJECTIVES

To (1) compare patients with sepsis with and without HIV, (2) assess whether HIV is associated with mortality in sepsis, and (3) identify factors associated with mortality in patients with HIV and sepsis.

METHODS

Patients who met Sepsis-3 criteria were studied. HIV infection was defined as administration of highly active antiretroviral therapy, a diagnosis of AIDS encoded by the International Classification of Diseases, or a positive HIV blood test result. Propensity scores were used to match patients with HIV to similar patients without HIV, and mortality was compared with χ2 tests. Logistic regression was used to determine factors independently associated with mortality.

RESULTS

Sepsis developed in 34 673 patients without HIV and 326 patients with HIV. Of these, 323 (99%) patients with HIV were matched to similar patients without HIV. The 30-60- and 90-day mortality was 11%, 15%, and 17%, respectively, in patients with sepsis and HIV, which was similar to the 11% (P > .99), 15% (P > .99), and 16% (P = .83) in patients without HIV. Logistic regression to adjust for confounders showed that obesity (odds ratio, 0.12; 95% CI, 0.03-0.46; P = .002) and high total protein on admission (odds ratio, 0.71; 95% CI, 0.56-0.91; P = .007) were associated with lower mortality. Mechanical ventilation at sepsis onset, renal replacement therapy, positive blood culture, and platelet transfusion were associated with increased mortality.

CONCLUSIONS

HIV infection was not associated with increased mortality in patients with sepsis.

Preclinical Drug Testing in Scalable 3D Engineered Muscle Tissues

Accurately modeling healthy and disease conditions in vitro is vital for the development of new treatment strategies and therapeutics. For cardiac and skeletal muscle diseases, contractile force and kinetics constitute key metrics for assessing muscle function. New and improved methods for generating engineered muscle tissues (EMTs) from induced pluripotent stem cells have made in vitro disease modeling more reliable for contractile tissues; however, reproducibly fabricating tissues from suspended cell cultures and measuring their contractility is challenging. Such techniques are often plagued with high failure rates and require complex instrumentation and customized data analysis routines. A new platform and device that utilizes 3D EMTs in conjunction with a label-free, highly-parallel, and automation-friendly contractility assay circumvent many of these obstacles. The platform enables facile and reproducible fabrication of 3D EMTs using virtually any cell source. Tissue contractility is then measured via an instrument that simultaneously measures 24 tissues without the need for complex software analysis routines. The instrument can reliably measure micronewton changes in force, allowing for dose-dependent compound screening to measure the effect of a drug or therapeutic on contractile output. Engineered tissues made with this device are fully functional, generating twitch and tetanic contractions upon electrical stimulation, and can be analyzed longitudinally in culture over weeks or months. Here, we show data from cardiac muscle EMTs under acute and chronic dosing with known toxicants, including a drug (BMS-986094) that was pulled from clinical trials after patient fatalities due to unanticipated cardiotoxicity. Altered skeletal muscle function in engineered tissues in response to treatment with a myosin inhibitor is also presented. This platform enables the researcher to integrate complex, information-rich bioengineered model systems into their drug discovery workflow with minimal additional training or skills required.

Cannabis Use Disorder in Adolescents

With increasing cannabis potency, increasing variety of methods of cannabis use, and lower perceived risk of cannabis use, it is increasingly important clinicians who work with adolescents remain up-to-date on the latest literature regarding cannabis use and its associated outcomes. Adolescent cannabis use is associated with chronic cognitive, psychosocial, psychiatric, and physical outcomes. Clinicians working in this field should be able to recognize cannabis use disorder, understand how adolescent cannabis use can impact the developing mind, and have informed discussions with patients and families regarding risks of use.

Abstract P1131: Modeling Contractile Diseases Using Scalable 3D Engineered Heart Tissues For Drug Discovery

Model systems that accurately recapitulate healthy and diseased function in a dish are critical for the development of novel therapeutics. For cardiac diseases, direct assessment of contractile output constitutes the most reliable metric with which to assess overall tissue function, as other ‘proxy’ measurements are poor predictors of muscle strength. 3D engineered muscle tissues (EMTs) derived from iPSCs hold great potential for modeling contractile function. Here, we have developed a platform and device that utilizes 3D EMTs in conjunction with a label-free magnetic sensing array. The platform enables facile and reproducible fabrication of 3D EMTs using virtually any cell source and is coupled with a highly parallel direct measurement of contractile strength. This approach enables the stratification of healthy and diseased phenotypes and facilitates compound safety and efficacy screening for evaluation of a drug’s effect on contractile output. We will present data from a drug (BMS-986094) that failed clinical trials due to unanticipated cardiotoxicity. We go on to show both the acute and chronic effects of doxorubicin in cardiac EMTs. Contractile force decreased in a dose dependent-like manner when the drug was applied continuously. Interestingly, a single 1uM bolus induced a transient effect that could be washed out over time. A repeat bolus, however, irreversibly abolished contraction, suggesting that repeat dosing may have a cardiotoxic effect on the muscle. These data demonstrate a first-and-only commercial platform for high-throughput assessment of 3D cardiac muscle contraction with potential for widespread adoption within the drug development field.

Use, and acceptability, of digital health technologies in musculoskeletal physical therapy: A survey of physical therapists and patients

Objectives

Determine (a) frequency of digital health use to obtain/record clinical information (pre‐COVID‐19); (b) willingness to use digital technologies among physical therapists and patients with musculoskeletal conditions.

Methods

102 physical therapists, and 103 patients were recruited in Australia. An electronic survey ascertained (a) demographic/clinical characteristics, (b) frequency of methods to obtain and record clinical information; (c) willingness to use digital technologies to support musculoskeletal care.

Results

Physical therapists mostly used non‐digital methods to obtain subjective (e.g., face‐to‐face questioning, n = 98; 96.1%) and objective information (e.g., visual estimation, n = 95; 93.1%). The top three digital health technologies most frequently used by therapists: photo‐based image capture (n = 19; 18.6%), accessing information logged/tracked by patients into a mobile app (n = 14; 13.7%), and electronic systems to capture subjective information that the patient fills in (n = 13; 12.7%). The top three technologies used by patients: activity trackers (n = 27; 26.2%), logging/tracking health information on mobile apps or websites (n = 12; 11.7%), and entering information on a computer (n = 12; 7.8%). Physical therapists were most willing to use technologies for: receiving diagnostic imaging results (n = 99; 97.1%), scheduling appointments (n = 92; 90.2%) and capturing diagnostic results (n = 92; 90.2%). Patients were most willing to use technologies for receiving notifications about health test results (n = 91; 88.4%), looking up health information (n = 83; 80.6%) and receiving personalised alerts/reminders (n = 80; 77.7%).

Conclusions

Physical therapists and patients infrequently use digital health technologies to support musculoskeletal care, but expressed some willingness to consider using them for select functions.

Honey authenticity: the opacity of analytical reports-part 2, forensic evaluative reporting as a potential solution

The analytical techniques applied to verify honey authenticity are multifaceted and often result in complex data rich certificates of analysis that are open to interpretation and may be opaque to stakeholders without specialist knowledge. In these cases, the drawing of an independent overarching opinion is challenging. Two questions arise: (Q1) Is it acceptable to report interpretation, particularly if it is adverse, without exhibiting the supporting data? (Q2) How may a valid overarching opinion on authenticity be derived from a large, partially conflicting, dataset? To Q1, it is demonstrated that full disclosure of the data used in interpretation is mandatory. To Q2 it is proposed, with worked examples, to adopt ‘evaluative reporting’; a formalised likelihood ratio thought process used in forensic science for evaluation of findings and their strength assessment. In the absence of consensus on techniques for honey authenticity adoption of reporting conventions will allow objective assessments of reports, with equity to all and provide a better basis to identify and address fraud.

High-throughput, real-time monitoring of engineered skeletal muscle function using magnetic sensing

Engineered muscle tissues represent powerful tools for examining tissue level contractile properties of skeletal muscle. However, limitations in the throughput associated with standard analysis methods limit their utility for longitudinal study, high throughput drug screens, and disease modeling. Here we present a method for integrating 3D engineered skeletal muscles with a magnetic sensing system to facilitate non-invasive, longitudinal analysis of developing contraction kinetics. Using this platform, we show that engineered skeletal muscle tissues derived from both induced pluripotent stem cell and primary sources undergo improvements in contractile output over time in culture. We demonstrate how magnetic sensing of contractility can be employed for simultaneous assessment of multiple tissues subjected to different doses of known skeletal muscle inotropes as well as the stratification of healthy versus diseased functional profiles in normal and dystrophic muscle cells. Based on these data, this combined culture system and magnet-based contractility platform greatly broadens the potential for 3D engineered skeletal muscle tissues to impact the translation of novel therapies from the lab to the clinic.

The feasibility of an online educational lifestyle program for people with multiple sclerosis: A qualitative analysis of participant semi-structured interviews

Objective

To explore the feasibility of a randomised controlled trial of a multiple sclerosis online course (MSOC) via qualitative analysis of participant semi-structured interviews.

Methods

The MSOC was developed in two arms: intervention arm which contained evidence-based lifestyle modification recommendations, and standard-care arm which delivered information from MS websites reflecting standard advice. Participants were recruited via online advertisements, completed a baseline questionnaire, and randomised. Seven modules were delivered over six weeks. Course completers were invited to participate in semi-structured interviews. Within a qualitative paradigm, interviews were analysed using reflexive thematic analysis.

Results

Fourteen of the 17 course completers were interviewed: 86% (12/14) female; mean age 50 years; residing in Australia, New Zealand, and the USA, predominantly had relapsing-remitting MS, mean time from diagnosis 9.5 years, and patient-determined disease steps disability assessment distributed evenly across all three categories. Four themes were identified: 1) “Hearing our stories” (hope for the future, feeling represented, exploring the journey of others with MS, learning from diversity, and wanting to connect with others); 2) “Taking the plunge” (not wanting to be first, feelings of nervousness or reluctance and feeling confronted); 3) “The accessibility and safety of being online” (ease of access, going at your own pace, making it work and not letting others down); and 4) “unpacking the course” (ease of navigation, visuals, understandability, and length and timing).

Conclusion

Participants felt represented, found the course accessible and content was easy to understand. These experiences provide important insights and considerations for this digital health intervention.

Characteristics of mHealth app use in an international sample of people with multiple sclerosis

The management of multiple sclerosis (MS) has progressed significantly with the emergence of mHealth technologies. Uptake of mHealth apps amongst people with MS, and clinical and demographic characteristics of mHealth adopters is unknown outside North America. Participants of the HOLISM study were queried about their mHealth apps use. We summarize mHealth app usage, and clinical and demographic characteristics of mHealth app adopters using descriptive statistics. Overall, 3.1% of respondents reported using an mHealth app, most of whom were located in Australasia and North America. This study provides insight regarding mHealth app usage within a large international cohort of people with MS.

426 PREVALENCE OF, AND RISK FACTORS FOR, DEMENTIA IN ADULT OUTPATIENT REFERRALS TO A REGIONAL REFERRAL HOSPITAL IN ARUSHA, TANZANIA

Introduction

The global burden of dementia is increasing, with the greatest increase predicted to occur in sub-Saharan Africa (SSA). Despite this there are limited previous data on the prevalence of, and risk factors for, dementia in SSA. This study aimed to estimate the prevalence of dementia, and investigate its associations, in those aged 60 years and older attending the outpatient department of Mount Meru Hospital in northern Tanzania. This is the first hospital-based outpatient dementia prevalence and risk factors study to be conducted in an east African population.

Methods

This was a one-phase cross-sectional study. Adults aged 60 years and over attending medical outpatients were screened for dementia using The Identification and Intervention for Dementia in Elderly Africans cognitive screening tool. Those who scored ≤9 were clinically assessed using the DSM-IV criteria. Demographic, medical comorbidity and lifestyle information were collected during a clinical assessment.

Results

Prevalence of dementia was 5.0% (95% confidence interval: 3.7–6.3). Binary logistic regression found female sex (odds ratio (OR) = 2.778), having no formal education (OR = 6.088), quantity of alcohol consumption (units/week) (OR = 1.080), uncorrected visual impairment (OR = 4.260), body mass index <18.5 kg/m2 (OR = 6.588) and stroke (OR = 15.790 with wide 95% confidence interval (3.48–74.475)) to be significantly, independently associated with dementia.

Conclusions

The prevalence of dementia in this population is lower than previously reported community-based rates in Tanzania, and similar to those in high-income countries. This is the first time the association between uncorrected visual impairment and dementia has been reported in SSA. Other associations identified are in keeping with previous literature. Further research on the management of dementia and its risk factors, and the support and education of carers and patients in east African populations is required.

Rates of Incidental Findings in Brain Magnetic Resonance Imaging in Children

Importance

Incidental findings (IFs) are unexpected abnormalities discovered during imaging and can range from normal anatomic variants to findings requiring urgent medical intervention. In the case of brain magnetic resonance imaging (MRI), reliable data about the prevalence and significance of IFs in the general population are limited, making it difficult to anticipate, communicate, and manage these findings.

Objectives

To determine the overall prevalence of IFs in brain MRI in the nonclinical pediatric population as well as the rates of specific findings and findings for which clinical referral is recommended.

Design, Setting, and Participants

This cohort study was based on the April 2019 release of baseline data from 11 810 children aged 9 to 10 years who were enrolled and completed baseline neuroimaging in the Adolescent Brain Cognitive Development (ABCD) study, the largest US population-based longitudinal observational study of brain development and child health, between September 1, 2016, and November 15, 2018. Participants were enrolled at 21 sites across the US designed to mirror the demographic characteristics of the US population. Baseline structural MRIs were centrally reviewed for IFs by board-certified neuroradiologists and findings were described and categorized (category 1, no abnormal findings; 2, no referral recommended; 3; consider referral; and 4, consider immediate referral). Children were enrolled through a broad school-based recruitment process in which all children of eligible age at selected schools were invited to participate. Exclusion criteria were severe sensory, intellectual, medical, or neurologic disorders that would preclude or interfere with study participation. During the enrollment process, demographic data were monitored to ensure that the study met targets for sex, socioeconomic, ethnic, and racial diversity. Data were analyzed from March 15, 2018, to November 20, 2020.

Main Outcomes and Measures

Percentage of children with IFs in each category and prevalence of specific IFs.

Results

A total of 11 679 children (52.1% boys, mean [SD] age, 9.9 [0.62] years) had interpretable baseline structural MRI results. Of these, 2464 participants (21.1%) had IFs, including 2013 children (17.2%) assigned to category 2, 431 (3.7%) assigned to category 3, and 20 (0.2%) assigned to category 4. Overall rates of IFs did not differ significantly between singleton and twin gestations or between monozygotic and dizygotic twins, but heritability analysis showed heritability for the presence or absence of IFs (h2 = 0.260; 95% CI, 0.135-0.387).

Conclusions and Relevance

Incidental findings in brain MRI and findings with potential clinical significance are both common in the general pediatric population. By assessing IFs and concurrent developmental and health measures and following these findings over the longitudinal study course, the ABCD study has the potential to determine the significance of many common IFs.

Rural, urban, and teaching hospital differences in hip fracture mortality

Introduction

Hip fractures remain one of the most prevalent and deadly conditions afflicting those 65 years and older. For other health conditions (e.g. myocardial infarction), hospital location is associated with poorer health outcomes. To our knowledge, no study has investigated the relationship between hip fracture morality rate in the United States between urban and rural hospital settings.

Methods

A retrospective cohort study was conducted to examine differences in in-hospital mortality between groups treated in rural, urban-teaching, and urban-non-teaching hospitals, as well as public and private hospitals. Mortality rates were also compared for variances between surgical treatment, sex, insurance, patient location, race, and income. Discharge data was collected for 256,240 inpatient stays from the 2012 National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Results

Odds of mortality were 14.6% greater in rural hospital hip fracture patients compared to Urban/Non-Teaching centers (p < 0.05).

Conclusions

Results from this study lend support to necessitate further research investigating prospective barriers to care of those in rural settings. This may point to limitations in resources and trained medical and surgical specialists in rural hospitals and need for continued research to mitigate such findings.

N-acetylcysteine for the treatment of comorbid alcohol use disorder and posttraumatic stress disorder: Design and methodology of a randomized clinical trial

Alcohol use disorder (AUD) and posttraumatic stress disorder (PTSD) are two prevalent psychiatric conditions in the U.S. The co-occurrence of AUD and PTSD is also common, and associated with a more severe clinical presentation and worse treatment outcomes across the biopsychosocial spectrum (e.g., social and vocational functioning, physical health) as compared to either disorder alone. Despite the high co-occurrence and negative outcomes, research on effective medications for AUD/PTSD is sparse and there is little empirical evidence to guide treatment decisions. The study described in this paper addresses this knowledge gap by testing the efficacy of N-acetylcysteine (NAC) in reducing alcohol use and PTSD symptoms. Animal studies and prior clinical research suggest a role for NAC in the treatment of substance use disorders and PTSD via glutamate modulation. NAC is a cysteine pro-drug that stimulates the cystine-glutamate exchanger, normalizes glial glutamate transporters, and restores glutamatergic tone on presynaptic receptors in reward regions of the brain. Moreover, NAC is available over-the-counter, has a long-established safety record, and does not require titration to achieve the target dose. This paper describes the rationale, study design, and methodology of a 12-week, randomized, double-blind, placebo-controlled trial of NAC (2400 mg/day) among adults with co-occurring AUD and PTSD. Functional magnetic resonance imaging (fMRI) and proton magnetic resonance spectroscopy (1H-MRS) are utilized to investigate the neural circuitry and neurochemistry underlying comorbid AUD/PTSD and identify predictors of treatment outcome. This study is designed to determine the efficacy of NAC in the treatment of co-occurring AUD/PTSD and provide new information regarding mechanisms of action implicated in co-occurring AUD/PTSD.

NanoMEA: A Tool for High-Throughput, Electrophysiological Phenotyping of Patterned Excitable Cells

Matrix nanotopographical cues are known to regulate the structure and function of somatic cells derived from human pluripotent stem cell (hPSC) sources. High-throughput electrophysiological analysis of excitable cells derived from hPSCs is possible via multielectrode arrays (MEAs) but conventional MEA platforms use flat substrates and do not reproduce physiologically relevant tissue-specific architecture. To address this issue, we developed a high-throughput nanotopographically patterned multielectrode array (nanoMEA) by integrating conductive, ion-permeable, nanotopographic patterns with 48-well MEA plates, and investigated the effect of substrate-mediated cytoskeletal organization on hPSC-derived cardiomyocyte and neuronal function at scale. Using our nanoMEA platform, we found patterned hPSC-derived cardiac monolayers exhibit both enhanced structural organization and greater sensitivity to treatment with calcium blocking or conduction inhibiting compounds when subjected to high-throughput dose-response studies. Similarly, hPSC-derived neurons grown on nanoMEA substrates exhibit faster migration and neurite outgrowth speeds, greater colocalization of pre- and postsynaptic markers, and enhanced cell-cell communication only revealed through examination of data sets derived from multiple technical replicates. The presented data highlight the nanoMEA as a new tool to facilitate high-throughput, electrophysiological analysis of ordered cardiac and neuronal monolayers, which can have important implications for preclinical analysis of excitable cell function.

Fructans in Foods and Food Products, Ion-Exchange Chromatographic Method: Collaborative Study

Nine collaborating laboratories assayed 6 blind duplicate pairs of food samples containing the fructans inulin or oligofructose. The 6 sample pairs ranged from low (4%) to high levels (40%). Following the proposed method, the samples were treated with amyloglucosidase and inulinase enzymes and the released sugars were determined byion exchange chromatography. Repeatability standard deviation ranged from 2.9 to 5.8%; reproducibility standard deviation ranged from 4.7 to 11.1%. The ion-exchange chromatographic method for determinationof fructans in food and food products has been adopted first action by AOAC INTERNATIONAL (997.08)

Abstract OT2-04-03: Examining personalized radiation therapy (EXPERT): A randomised phase III trial of adjuvant radiotherapy vs observation in patients with molecularly characterized luminal A breast cancer

Background

Radiation therapy (RT) after breast conserving surgery (BCS) is the current standard of care for patients with early stage breast cancer. However, individual absolute recurrence risks and hence benefits of RT vary substantially. A study showed significant association between local recurrence (LR) risk and PAM50-defined intrinsic subtypes and Risk of Recurrence scores (ROR).1

The objective of EXPERT, a co-lead study of Breast Cancer Trials-Australia & New Zealand (BCT-ANZ), and Breast International Group (BIG), is to optimize local therapy for early breast cancer through precise individualized quantification of LR risk to identify patients for whom RT after BCS may be safely omitted.

Trial design

This is a randomized, non-inferiority, phase III study of women who plan to receive adjuvant endocrine therapy for Prosigna (PAM50)-defined luminal A breast cancer with ROR ≤60 resected by BCS.

Women are randomized to receive adjuvant whole breast RT and endocrine therapy or endocrine therapy alone and followed-up for 10 years after randomization.

Major eligibility criteria

Females aged ≥50 years; histologically confirmed invasive breast carcinoma ≤2 cm, grade 1 or 2, ER and PgR ≥10%, HER2-negative and node-negative; treated by BCS with negative margins for invasive carcinoma and associated DCIS; Prosigna (PAM50)-defined Luminal A subtype and ROR ≤60; and plan to receive adjuvant endocrine therapy.

Specific aims

Primary: To determine if omission of RT is not inferior to RT in terms of LR-free interval after BCS.

Secondary: To evaluate the impact of omission of RT on regional, local-regional and distant recurrence-free interval; disease-free survival (DFS); invasive DFS; overall survival; salvage RT or mastectomy rate; toxicity; endocrine therapy adherence; patient reported outcomes; and health economic outcomes.

Statistical methods

An estimated 5-year LR rate in the target population is expected to be 1% with RT. A rate of 4% is considered non-inferior as a worthwhile trade-off against RT toxicity. Using O'Brien-Fleming boundary for rejecting non-inferiority, 29 LR events are required for final analysis expected 8 years after the first patient is randomized. Two interim analyses will be conducted after 10 and 21 events. If the stratified log-rank test statistic exceeds the upper boundary at interim or final analysis, the hypothesis of non-inferiority will be rejected and it will be concluded that no RT is inferior to RT.

Accrual: Target (1170), actual: 82 (June 2018)

The study was activated in Australia in August 2017, with global activation planned for Q4 2018. Recruitment is expected to be completed in 4.5 years.

Contact information

Professor Boon Chua, UNSW Sydney and Prince of Wales Hospital, NSW, Australia; email boon.chua@health.nsw.gov.au; T +61 2 49255239. Registration: NCT02889874

References

Fitzal F, Filipits M, Fesl C, et al. Predicting local recurrence using PAM50 in postmenopausal endocrine responsive breast cancer patients. JCO 2014;32(15 suppl):1008.

Citation Format: Chua BH, Gray K, Krishnasamy M, Regan M, Zdenkowski N, Loi S, Mann B, Forbes JF, Wilcken N, Spillane A, Martin A, Badger H, Jafari S, Fong A, Mavin C, Corachan S, Arahmani A, Martinez J-L, Francis P. Examining personalized radiation therapy (EXPERT): A randomised phase III trial of adjuvant radiotherapy vs observation in patients with molecularly characterized luminal A breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-04-03.

Abstract P4-14-01: Estrogen levels in premenopausal patients (pts) with hormone-receptor positive (HR+) early breast cancer (BC) receiving adjuvant triptorelin (Trip) plus exemestane (E) or tamoxifen (T) in the SOFT trial: SOFT-EST substudy final analysis

Background: Optimal endocrine therapy for premenopausal pts with early HR+ BC may depend on complete estrogen suppression with GnRH analog, which is crucial when using concurrent aromatase inhibitors (AIs). SOFT-EST is a prospective substudy of the phase 3 SOFT trial aiming to describe estradiol (E2), estrone (E1) and estrone sulphate (E1S) during the first 4 years (y) of monthly Trip+E/T and to assess if there were suboptimally estrogen suppressed (SES) pts in the E+Trip group. Secondary objectives included associations of baseline (BL) factors with SES, early SES with later SES, and SES with disease-free survival (DFS; exploratory objective).

Methods: Patients from select centers who consented and enrolled in SOFT, selected Trip as ovarian function suppression method, and were randomized to E+Trip or T+Trip were eligible for SOFT-EST until the accrual goal (120 pts: 90 E+Trip; 30 T+Trip). Prem status for SOFT eligibility was based on local E2. Blood sampling timepoints were 0, 3, 6, 12, 18, 24, 36 & 48 months (m) until Trip stopped. Serum estrogens were measured centrally by high specificity/sensitivity GC/MSMS and were not available during the study. For 4y analyses, SES was defined as E2 levels &gt;2.72 pg/mL in ≥2 post-BL samples (E2 levels not consistent with postmenopausal (PM) status on AIs [Smith IE, JCO 2006]), or vaginal bleeding &gt;3m after Trip start, or pregnancy. We explored 2 additional cutoffs: &gt;10 pg/mL (clearly inconsistent with PM status on AIs) and &gt;20 pg/mL (inconsistent with GnRH analog-related PM status). The analysis is intention-to-treat based on E/T assignment; as-treated analyses are forthcoming.

Results: From Mar 2009 to Jan 2011,109 pts (E/T=83/26) started Trip and had ≥2 samples drawn. In pts assigned E+Trip, median reductions from BL in E1, E2 and E1S were &gt;95% at all timepoints and significantly lower than in T+Trip. Post-BL E2 geometric mean ranged 0.8-1.3 pg/mL in E+Trip and 16.5-18.3 pg/mL in T+Trip. 21 (25%), 11 (13%) and 6 (7%) pts assigned to E+Trip had E2&gt;2.72, &gt;10, and &gt;20 pg/mL in ≥2 post BL samples or vaginal bleeding (n=3), respectively. Early SES [(≥1 E2 value &gt;2.72 pg/mL or vaginal bleeding in the firsty] predicted later SES [≥1 E2 value &gt;2.72 or vaginal bleeding thereafter (n=1); p&lt;0.001]. BL factors related to SES were higher E2, lower FSH and lower LH values (p=0.02, p&lt;0.01, p&lt;0.01 respectively). 12m FSH levels were not related to SES. In pts assigned E+Trip, after 6y median follow-up, DFS events were seen in 0 of 21 pts with SES vs 5 of 62 pts without SES.

Conclusions: Most pts on E+Trip had a profound E2 drop consistent with postmenopausal status on AI, but &gt;20% assigned to E+Trip had ≥2 E2 values &gt;2.72 pg/mL and 4% had vaginal bleeding, with those having higher E2, lower FSH/LH at BL being at higher risk. SES at 12m predicted subsequent SES. Few DFS events limit the ability to assess clinical relevance of SES with disease outcomes.

BL characteristicsN-109Prior chemo60 (55%)Amenorrhea39 (36%)Age &lt;35y8 (7%) Median (range)Age, y44 (25-53)BMI, kg/m224 (22-28)Estrogen (pg/mL) E252 (7-119)E141 (24-70)E1S894 (304-1320)FSH/LH (IU/L) FSH15 (7-47)LH11 (6-26)

Citation Format: Bellet M, Gray K, Francis P, Láng I, Ciruelos E, Lluch A, Ángel Climent M, Catalán G, Avella A, Bohn U, González-Martin A, Zaman K, Ferrer R, Azaro A, Rajasekaran A, De la Peña L, Fleming G, Regan MM. Estrogen levels in premenopausal patients (pts) with hormone-receptor positive (HR+) early breast cancer (BC) receiving adjuvant triptorelin (Trip) plus exemestane (E) or tamoxifen (T) in the SOFT trial: SOFT-EST substudy final analysis [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-14-01.

Current, future and potential use of mobile and wearable technologies and social media data in the ABCD study to increase understanding of contributors to child health

Mobile and wearable technologies and novel methods of data collection are innovating health-related research. These technologies and methods allow for multi-system level capture of data across environmental, physiological, behavioral, and psychological domains. In the Adolescent Brain Cognitive Development (ABCD) Study, there is great potential for harnessing the acceptability, accessibility, and functionality of mobile and social technologies for in-vivo data capture to precisely measure factors, and interactions between factors, that contribute to childhood and adolescent neurodevelopment and psychosocial and health outcomes. Here we discuss advances in mobile and wearable technologies and methods of analysis of geospatial, ecologic, social network and behavioral data. Incorporating these technologies into the ABCD study will allow for interdisciplinary research on the effects of place, social interactions, environment, and substance use on health and developmental outcomes in children and adolescents.

Abstract P1-10-06: A randomized phase II trial evaluating the endocrine activity and efficacy of neoadjuvant degarelix versus triptorelin in premenopausal patients receiving letrozole for primary endocrine responsive breast cancer (TREND; IBCSG 41-13)

Background: Neoadjuvant endocrine therapy (NET) with gonadotropin-releasing hormone (GnRH) agonist and aromatase inhibitors is effective in selected premenopausal patients (pts). Degarelix, an antagonist of GnRH, has immediate onset of action through binding to GnRH receptors in the pituitary gland and thereby suppressing the production of LH and FSH. Its suppressing activity in premenopausal women might be faster and free of estrodial breakthrough on continued treatment compared with a GnRH angonist, and thereby provide significant clinical value for pts who are candidates for short-term NET.

Methods: Eligible pts were premenopausal women with cT2-4b, any nodal stage, ER and PgR &gt;50%, HER2-negative (by IHC and/or ISH) breast cancer who were not candidates for breast conserving surgery. Premenopausal status was determined locally with estradiol (E2) levels &gt;54 pg/mL (or &gt;198 pmol/L), measured within 14 days prior to randomization. Pts were randomized 1:1 to Triptorelin (T) 3.75 mg i.m. on day 1 of every cycle or Degarelix (D) 240 mg s.c. given as two injections of 120 mg on day 1 of cycle 1, then 80 mg s.c. on day 1 of cycles 2-6 with letrozole (L) 2.5 mg/day for 6 cycles. Each cycle was 28 days. Definitive surgery was performed within 2-3 weeks after the last administration of T or D. Serum was collected prior to the first injection (baseline), 24 and 72 hours, 7 and 14 days, then prior to injection on day 1 of cycles 2-6. The primary endpoint was time to optimal ovarian function suppression (OFS) calculated as time from the first injection of D or T to the first assessment of centrally assessed 17-β-estradiol (E2) level in the range of optimal OFS (≤2.72 pg/mL or ≤10 pmol/L) during the 6 cycles of NET. The trial had 90% power to detect a difference using a logrank test, 2-sided α=0.05. Secondary endpoints included tolerability, Ki67changes, PEPI score, best overall response. NCT02005887

Results: TREND completed accrual of 51 pts in January 2017. A preliminary analysis based on the first 45 pts is reported here. 89% of patients were ≥40 yrs, 76% had T1-2 and 22% T3 tumors, and 51% were node-positive. Dominant histology type was ductal (93%). The table summarizes centrally-assessed E2 according to treatment at baseline and for the first 5 assessment time points indicating immediate suppression for the D+L arm. E2 levels on day 1 of cycles 2-6 were all below the limit of quantification (0.625 pg/mL) for the D+L arm. For the T+L arm continued OFS was not maintained in 4 pts.

 BaselineCycle 1Cycle 2Day:01371429No. Pts      D+L222221212221T+L232321232222Median (IQR)     D+L96.2 (64.2,206.8)10.1 (4.0,21.8)0.6 (0.6,1.0)0.6 (0.6,0.6)0.6 (0.6,0.6)0.6 (0.6, 0.6)T+L85.1 (49.7,118.0)37.4 (17.9,59.2)12.8 (7.7,23.8)9.0 (1.2,29.7)0.6 (0.6,1.4)0.6 (0.6, 0.6)

Conclusion: Evidence from this first analysis demonstrates rapid and maintained OFS with the combination of D+L as a NET in premenopausal breast cancer patients. The final analysis of the total population, including secondary endpoints, will be presented at the symposium.

Citation Format: Colleoni M, Gray K, Munzone E, Dellapasqua S, Zamagni C, Gianni L, Johansson H, Viale G, Kammler R, Maibach R, Rabaglio-Poretti M, Di Leo A, Coates AS, Gelber RD, Regan MM, Goldhirsch A. A randomized phase II trial evaluating the endocrine activity and efficacy of neoadjuvant degarelix versus triptorelin in premenopausal patients receiving letrozole for primary endocrine responsive breast cancer (TREND; IBCSG 41-13) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-10-06.

Modeling response to heat stress in pigs from nucleus and commercial farms in different locations in the United States

The purpose of this study was to analyze the impact of seasonal losses due to heat stress in different environments and genetic group combinations. Data were available for 2 different swine populations: purebred Duroc animals raised in nucleus farms in Texas and North Carolina and crosses of Duroc and F females (Landrace × Large White) raised in commercial farms in Missouri and North Carolina; pedigrees provided links between animals from different states. Traits included BW at harvest age for purebred animals and HCW for crossbred animals. Weather data were collected at airports located close to the farms. Heat stress was quantified by a heat load function, defined by the units of temperature-humidity of temperature-humidity index (THI) greater than a certain threshold for 30 to 70 d before phenotype collection. Heat stress responses were quantified by a linear regression of phenotype on heat load. The greatest coefficient of determination occurred with a length of 30 d before phenotype measurements for all states and genetic groups. In the crossbreed data, THI thresholds were 67 in Missouri and 72 in North Carolina. For pure breeds, heat load had the best fit for THI thresholds greater than 70 in North Carolina, although differences in coefficient of determinations were negligible. On the other hand, no optimal THI threshold existed in Texas. In this study, heat stress had a greater impact in commercial farms than in nucleus farms and the effect of heat stress on weight varied by year and state.

Predictive equations of selenium accessibility of dry pet foods

The trace element selenium is essential to both dogs and cats. Dry diets are formulated with a large range of ingredients, which may vary in selenium concentration and accessibility. This paper reports equations to predict the average in vitro selenium accessibility from dry pet foods based on essential dietary nutrient concentrations, including crude protein, amino acids and crude fat. Predictive equations were made using stepwise linear regression for extruded and pelleted diets. The equations can be used to aid diet formulation to optimize selenium accessibility within the diet and to prevent selenium deficiency or toxicity.

Migrant Labor and Civil Society Relations in South Korea

Nearly two decades have passed since migrant workers first entered Korea to fill labor shortages in the small and medium business sector. In response to the many difficulties faced by migrant workers in this highly exploitative sector of the economy, a dynamic civil society movement has emerged to provide day-to-day support for the migrant workers as well as propose alternative policy frameworks for their employment. Whilst the important role played by these organizations has been recognized, migrant worker activists have criticized this movement as being paternalistic and unresponsive to the needs and concerns of the migrant workers themselves. Migrant workers have accordingly begun to organize themselves and to directly to pursue their own interests, and there have also been tentative movements towards solidarity between migrant workers and the domestic labor movement. Despite the political significance of these developments, migrant worker activists remain in a highly vulnerable position and the continued development of this movement is by no means guaranteed.

The effect of 48-hour fasting on taurine status in healthy adult dogs

Low circulating taurine concentrations may be a risk factor for dilated cardiomyopathy (DCM) in dogs. Circulating taurine is typically measured in the clinic 4-5 h after feeding, largely because the impact of later sampling is not known. The objective of this study was to measure taurine in the blood during a 48-h fast in 12 healthy adult Labrador Retrievers to refine sampling methodology for determination of taurine status. Plasma and whole blood (WB) taurine concentrations did not fall to levels indicative of clinical deficiency throughout fasting; WB was the more reliable indicator of taurine status. This study shows that blood samples can be taken for assessment of taurine status any time up to 48 h after ingestion of a meal in healthy adult dogs.

Genetic analysis of sow longevity and sow lifetime reproductive traits using censored data

Sow longevity is a key component for efficient and profitable pig farming; however, approximately 50% of sows are removed annually from a breeding herd. There is no consensus in the scientific literature regarding a definition for sow longevity; however, it has been suggested that it can be measured using several methods such as stayability and economic indicators such as lifetime piglets produced. Sow longevity can be improved by genetic selection; however, it is rarely included in genetic evaluations. One reason is elongated time intervals required to collect complete lifetime data. The effect of genetic parameter estimation software in handling incomplete data (censoring) and possible early indicator traits were evaluated analysing a 30% censored data set (12 725 pedigreed Landrace × Large White sows that included approximately 30% censored data) with DMU6, THRGIBBS1F90 and GIBBS2CEN. Heritability estimates were low for all the traits evaluated. The results show that the binary stayability traits benefited from being analysed with a threshold model compared to analysing with a linear model. Sires were ranked very similarly regardless if the program handled censoring when all available data were included. Accumulated born alive and stayability were good indicators for lifetime born alive traits. Number of piglets born alive within each parity could be used as an early indicator trait for sow longevity.

Control of the interface between heterotypic cell populations reveals the mechanism of intercellular transfer of signaling proteins

Direct intercellular transfer of cellular components is a recently described general mechanism of cell–cell communication. It is a more non-specific mode of intercellular communication that is not actively controlled by the participating cells. Though membrane bound proteins and small non-protein cytosolic components have been shown to be transferred between cells, the possibility of transfer of cytosolic proteins has not been clearly established, and its mechanism remains unexplained. Using a cell–cell pair of metastatic melanoma and endothelial cells, known to interact at various stages during cancer progression, we show that cytosolic proteins can indeed be transferred between heterotypic cells. Using precise relative cell patterning we provide evidence that this transfer depends on extent of the interface between heterotypic cell populations. This result is further supported by a mathematical model capturing various experimental conditions. We further demonstrate that cytosolic protein transfer can have important functional consequences for the tumor–stroma interactions, e.g., in heterotypic transfer of constitutively activated BRAF, a common melanoma associated mutation, leading to an enhanced activation of the downstream MAPK pathway. Our results suggest that cytosolic protein transfer can have important consequences for regulation of processes involving physical co-location of heterotypic cell types, particularly in invasive cancer growth.

Cognitive training as a resolution for early executive function difficulties in children with intellectual disabilities

Core executive functions (EF) such as attention, and working memory have been strongly associated with academic achievement, language development and behavioral stability. In the case of children who are vulnerable to cognitive and learning problems because of an underlying intellectual disability, EF difficulties will likely exacerbate an already compromised cognitive system. The current review examines cognitive training programs that aim to improve EF, specifically focusing on the potential of this type of intervention for children who have intellectual disabilities. We conclude that despite considerable discrepancies regarding reported intervention effects, these inconsistencies can be attributed to flaws in both program and study design. We discuss the steps needed to address these limitations and to facilitate the advancement of non-pharmaceutical interventions for children with intellectual disabilities.

Potent and specific inhibition of the biological activity of the type-II transmembrane serine protease matriptase by the cyclic microprotein MCoTI-II

Matriptase is a type-II transmembrane serine protease involved in epithelial homeostasis in both health and disease, and is implicated in the development and progression of a variety of cancers. Matriptase mediates its biological effects both via as yet undefined substrates and pathways, and also by proteolytic cleavage of a variety of well-defined protein substrates, several of which it shares with the closely-related protease hepsin. Development of targeted therapeutic strategies will require discrimination between these proteases. Here we have investigated cyclic microproteins of the squash Momordica cochinchinensis trypsin-inhibitor family (generated by total chemical synthesis) and found MCoTI-II to be a high-affinity (Ki 9 nM) and highly selective (> 1,000-fold) inhibitor of matriptase. MCoTI-II efficiently inhibited the proteolytic activation of pro-hepatocyte growth factor (HGF) by matriptase but not by hepsin, in both purified and cell-based systems, and inhibited HGF-dependent cell scattering. MCoTI-II also selectively inhibited the invasion of matriptase-expressing prostate cancer cells. Using a model of epithelial cell tight junction assembly, we also found that MCoTI-II could effectively inhibit the re-establishment of tight junctions and epithelial barrier function in MDCK-I cells after disruption, consistent with the role of matriptase in regulating epithelial integrity. Surprisingly, MCoTI-II was unable to inhibit matriptase-dependent proteolytic activation of prostasin, a GPI-anchored serine protease also implicated in epithelial homeostasis. These observations suggest that the unusually high selectivity afforded by MCoTI-II and its biological effectiveness might represent a useful starting point for the development of therapeutic inhibitors, and further highlight the role of matriptase in epithelial maintenance.

Abstract S6-05: High levels of APOBEC3B, a DNA deaminase and an enzymatic source of C-to-T transitions, are a validated marker of poor outcome in estrogen receptor-positive breast cancer

Two recent observations have connected the innate immune DNA cytosine deaminase APOBEC3B to the genetic evolution of breast cancer. First, APOBEC3B was shown to be up-regulated in the majority of breast cancers, and, in breast cancer cell lines, its activity was causally linked to a doubling of the number of C-to-T transitions over time and to a delay in cell cycle progression (1). Second, sequencing of the complete genome of 21 breast cancers independently suggested that APOBEC deaminase activity could be responsible for 2 of 5 mutational imprints identified, which involved clustered (also called kataegis) and dispersed C-to-T transition mutations in the context of 5’TC dinucleotide motifs (2).

In the current study, we addressed a possible association of APOBEC3B expression with outcome in clinical breast cancer. For this we measured using real-time RT-PCR APOBEC3B mRNA levels in 1,491 primary invasive breast cancers and correlated these levels with disease-free survival (DFS), metastasis-free survival (MFS) and overall survival (OS) using univariate and multivariable Cox regression analysis. In addition, we independently validated our findings in available gene expression datasets with appropriate follow-up.

In univariate analyses including all patients, increasing levels of APOBEC3B mRNA analyzed as a continuous variable were significantly associated with shorter DFS, MFS and OS (Hazard Ratio [HR] = 1.29, 1.31 and 1.36, respectively, all P&lt;0.001). To determine the relation of APOBEC3B mRNA expression with the natural course of the disease without the potential confounding effects of systemic adjuvant therapy, we restricted our next analyses to MFS in 829 patients with lymph node-negative disease who had not received any (neo)adjuvant systemic therapy. This analysis showed that APOBEC3B mRNA expression was, in univariate, and in multivariable analysis, including the traditional prognostic factors (age, menopausal status, tumor size, grade and steroid hormone receptors), a marker of pure prognosis specifically in patients with estrogen receptor-positive (ER+) disease (univariate HR = 1.30; P = 0.003; multivariate HR = 1.22, P = 0.042).

To substantiate and validate our findings, we analysed 4 independent available datasets containing in total 5,760 breast cancer cases in which APOBEC3B mRNA expression was measured by probes on microarrays and found that higher APOBEC3B mRNA expression (dichotomised by mean) was significantly associated with poor outcome in all 4 cohorts ([Metabric, 1,491 ER+ cases, HR = 1.82; P&lt;0.001], [Affymetrix compiled dataset-1, 2,407 cases, HR = 2.22; P = 0.001], and [BIG 1-98; 1,207 cases, HR = 2.13; P&lt;0.001 of late recurrence&gt;5 years], and [Affymetrix dataset-2, 643 ER+ cases, HR = 2.04; P = 0.001]).

Altogether, our analyses show that APOBEC3B mRNA - and as a result likely DNA deamination – is a validated predictor of poor outcome in breast cancer, supporting the notion that APOBEC3B is a potentially interesting clinical target for therapeutic intervention to prevent breast cancer progression and metastasis, particularly in ER+ disease.

1. Burns, M.B. et al. Nature 494, 366-70 (2013); 2. Nik-Zainal, S. et al. Cell 149, 979-93 (2012).

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr S6-05.

Abstract PD10-03: Predictive value of a proliferation score (MS) in postmenopausal women with endocrine-responsive breast cancer: results from International Breast Cancer Study Group (IBCSG) Trial IX

Background: While representing the largest fraction of women diagnosed with primary breast cancer, older postmenopausal women with ER+, HER2− tumors are less responsive to chemoendocrine therapy than younger women and have been underrepresented in molecular profiling of randomized trials. IBCSG Trial IX, a randomized controlled trial in postmenopausal women, median age 61y, with node negative disease, failed to demonstrate the benefit of preceding tamoxifen (T) by 3 cycles of CMF for ER+ tumors. We sought to determine if MS, a proliferation score, could identify a subset of women who differentially benefit from addition of chemotherapy to T in this trial.

Methods: From 1988–1999, 1669 eligible patients (1040 with ER+, HER2− tumors) were randomized to CMF→T vs T. Disease-free survival (DFS) was the primary trial endpoint; breast cancer-free interval (BCFI) which excludes second (non-breast) malignancies and censors deaths without prior cancer event was also evaluated. Analysis was limited to the first 7 years of follow-up. From 671 (ER+, HER2−) available subjects, 568 were successfully profiled by RT-PCR. The mRNA expression levels of 14 equally-weighted proliferation genes and 3 normalization genes were used to generate MS; predetermined binary categorization of MS was used. Analysis of this post hoc, pre-specified study used results from centralized laboratory IHC and Cox models to assess the predictive value of MS on DFS and BCFI, adjusting for traditional risk factors of local treatment, age, ER, PR, Ki67, tumor size and grade.

Results: Subgroups of MS (low, 169 samples (30%) and high, 399 samples (70%)) were identified. MS by treatment interaction was significant for DFS and BCFI (each p ≤ 0.004). Among patients with low MS, CMF→T improved DFS (HR 0.19, 95% CI 0.06–0.59) and BCFI (HR 0.19, 95% CI 0.05–0.72) vs T; 7y DFS was 95% vs 83% with CMF→T vs T. Among patients with high MS, CMF→T did not improve DFS (HR 1.27, 95% CI 0.79–2.05) or BCFI (HR 1.37, 95% CI 0.80–2.33) and 7y DFS of 81% for CMF→T and T. Continuous MS was moderately correlated with log Ki67 (r = 0.47) but not correlated with ER or PR. The MS by treatment interaction remained significant with Ki67 in the model.

Conclusions: Low MS was associated with differential benefit favoring those women receiving CMF→T vs T alone for both DFS and BCFI in the first 7 years. The effect was independent of traditional risk factors including Ki67. Hence this study, which is unconfounded by chemotherapy-induced ovarian ablation in younger women, identifies a subset of postmenopausal women with ER+, HER2− tumors that benefit from CMF chemotherapy. This seemingly incongruous observation is consistent with a) the prior observation that only the low-proliferation subgroup by PAM50 11-gene signature benefits from the addition of weekly paclitaxel to adjuvant FEC (GEICAM/9906), b) the ability of MS to identify a subset of women with tumors with disseminated luminal progenitor cells activated through the agonistic activity of tamoxifen, and c) the repetitive dosing of cyclophosphamide and taxol being hypothesized to act via tumor stroma/anti-angiogenesis. The relative contribution of these factors is under investigation.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD10-03.

Haemophilus influenzae serotype B (Hib) seroprevalence in England and Wales in 2009

A national seroprevalence study was performed to determine the prevalence of Haemophilus influenzae type b (Hib) antibodies in England and Wales in 2009, when Hib disease incidence was the lowest ever recorded. A total of 2,693 anonymised residual sera from routine diagnostic testing submitted by participating National Health Service hospital laboratories were tested for Hib anti-polyribosyl-ribitol phosphate (PRP) IgG antibodies using a fluorescent bead assay. Median anti-PRP IgG concentrations were highest in toddlers aged 1–4 years (2.65 μg/ml), followed by children aged 5–9 years (1.95 μg/ml). Antibody concentrations were significantly lower after this age, but were still significantly higher among 10–19 year-olds (0.54 μg/ml) compared with adults aged >20 years (0.16 μg/ ml; p<0.0001). Half of the adults (51%) did not have Hib antibody concentrations ≥0.15 μg/ml, the level considered to confer short-term protection. Thus, the current excellent Hib control appears to be the result of high anti-PRP antibody concentrations in children aged up to 10 years, achieved through the various childhood vaccination campaigns offering booster immunisation. The lack of seroprotection in adults emphasises the importance of maintaining control of the disease and, most probably carriage, in children, therefore raising the question as to whether long-term routine boosting of either pre-school children or adolescents may be required.