Identification of Biological Pathways to Alzheimer's Disease Using Polygenic Scores

Introduction

Single nucleotide polymorphisms (SNPs) contribute small increases in risk for late-onset Alzheimer's disease (LOAD). LOAD SNPs cluster around genes with similar biological functions (pathways). Polygenic risk scores (PRS) aggregate the effect of SNPs genome-wide. However, this approach has not been widely used for SNPs within specific pathways.

Objectives

We investigated whether pathway-specific PRS were significant predictors of LOAD case/control status.

Methods

We mapped SNPs to genes within 8 pathways implicated in LOAD. For our polygenic analysis, the discovery sample comprised 13,831 LOAD cases and 29,877 controls. LOAD risk alleles for SNPs in our 8 pathways were identified at a P-value threshold of 0.5. Pathway-specific PRS were calculated in a target sample of 3332 cases and 9832 controls. The genetic data were pruned with R2 > 0.2 while retaining the SNPs most significantly associated with AD. We tested whether pathway-specific PRS were associated with LOAD using logistic regression, adjusting for age, sex, country, and principal components. We report the proportion of variance in liability explained by each pathway.

Results

The most strongly associated pathways were the immune response (NSNPs = 9304, = 5.63 × 10−19, R2 = 0.04) and hemostasis (NSNPs = 7832, P = 5.47 × 10−7, R2 = 0.015). Regulation of endocytosis, hematopoietic cell lineage, cholesterol transport, clathrin and protein folding were also significantly associated but accounted for less than 1% of the variance. With APOE excluded, all pathways remained significant except proteasome-ubiquitin activity and protein folding.

Conclusions

Genetic risk for LOAD can be split into contributions from different biological pathways. These offer a means to explore disease mechanisms and to stratify patients.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Randomised crossover trial of telemonitoring in chronic respiratory patients (TeleCRAFT trial)

Objective

To assess the impact of home telemonitoring on health service use and quality of life in patients with severe chronic lung disease.

Design

Randomised crossover trial with 6 months of standard best practice clinical care (control group) and 6 months with the addition of telemonitoring.

Participants

68 patients with chronic lung disease (38 with COPD; 30 with chronic respiratory failure due to other causes), who had a hospital admission for an exacerbation within 6 months of randomisation and either used long-term oxygen therapy or had an arterial oxygen saturation (SpO₂) of <90% on air during the previous admission. Individuals received telemonitoring (second-generation system) via broadband link to a hospital-based care team.

Outcome measures

Primary outcome measure was time to first hospital admission for an acute exacerbation. Secondary outcome measures were hospital admissions, general practitioner (GP) consultations and home visits by nurses, quality of life measured by EuroQol-5D and hospital anxiety and depression (HAD) scale, and self-efficacy score (Stanford).

Results

Median (IQR) number of days to first admission showed no difference between the two groups—77 (114) telemonitoring, 77.5 (61) control (p=0.189). Hospital admission rate at 6 months increased (0.63 telemonitoring vs 0.32 control p=0.026). Home visits increased during telemonitoring; GP consultations were unchanged. Self-efficacy fell, while HAD depression score improved marginally during telemonitoring.

Conclusions

Telemonitoring added to standard care did not alter time to next acute hospital admission, increased hospital admissions and home visits overall, and did not improve quality of life in chronic respiratory patients.

Trial registration number

NCT02180919 (ClinicalTrials.gov).

Abstract P5-11-02: Survival benefit needed to undergo chemotherapy: Patients and physicians preferences

Background: Data regarding patients (pts) and physicians' preferences for modern adjuvant chemotherapy (CT) are limited. Prior studies suggested that most pts with early stage breast cancer were willing to receive 6 months of adjuvant cyclophosphamide, methotrexate, and 5-fluorouracil (CMF) for modest survival benefits (e.g. most women would have accepted 3-6 months extension of life).

Methods: E5103 was a phase III trial which randomized node positive or high risk node negative breast cancer pts to receive adjuvant CT (doxorubicin, cyclophosphamide and paclitaxel) with either placebo or bevacizumab. Telephone based surveys were administered to all pts enrolled on E5103 between 01/Jan/10 and 08/Jun/10, as part of a Decision-Making/Quality of Life component. Results presented here are part of the 18 months post-enrollment follow-up. Pts were asked to rate the survival benefit needed to justify 6 months of CT. A complementary survey was sent to all physicians who registered at least one pt on E5103.

Results: 465 out of 519 eligible pts (90%) responded to this survey at 18 months. Main reasons for non response were: inability to reach the patient (6%) or patient refusal (2%). Median pts age was 51 (25-76); 42% of pts had at least a college degree. The majority had at least Stage II cancer.

179 (16%) physicians participated, among whom median age was 50 (35-70). The median years in practice was 17 (3-38); 78% of physicians worked on large size practices, 72% saw at least 5 new breast cancer pts/month, and 77% enroll between 1-4 pts on trials/month.

We found considerable variation in pts preferences particularly for modest survival benefits: a substantial minority of pts (24%) would consider 6 months of CT definitely worthwhile for 1 month survival benefit, 18% would possibly consider it and 56% would not. The percentage considering CT definitely worthwhile increased with greater benefit, but did not reach 100%, even with 24 months survival benefit. About half of pts considered 6 months of CT definitely worthwhile for 9 months benefit, 70% for 12 months and 84% for 24 months.

Physicians were less likely to accept CT for a small chance of benefit (34% of pts vs. 5% of physicians would definitely consider CT worthwhile for 2 months of benefit). For longer benefit, pts and physicians choices were similar (84% of pts vs. 92% of physicians would definitely consider CT worthwhile for 24 months benefit).

Table Yes, definitely worthwhileYes, maybeNo, not worthwhileNo answerConsider 6 months of CT to live:PtsPhysiciansPtsPhysiciansPtsPhysiciansPts/Physicians*1 month longer24%3%18%15%56%80%2%2 months longer34%5%23%32%41%60%2%6 months longer44%32%35%54%19%12%2%9 months longer53%51%34%42%11%5%2%12 months longer70%75%23%22%5%1%2%24 months longer84%92%12%5%2%1%2%n Pts= 465; n Physicians= 179; * equal results in both groups

Conclusions: This subgroup of pts who had undergone modern adjuvant CT in a large multicenter randomized controlled trial and these physicians who registered pts on the same trial had different cutoffs for acceptable levels of benefits and risks when considering adjuvant chemotherapy. It is important to engage pts in determining whether CT is or is not a "reasonable" option for treatment.

Citation Format: Vaz Luis I, O'Neill A, Sepucha K, Miller KD, Baker E, Dang CT, Northfelt DW, Winer EP, Sledge GW, Schneider BP, Partridge A. Survival benefit needed to undergo chemotherapy: Patients and physicians preferences. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-11-02.

Subjective religiosity, church attendance, and depression in the National Survey of American Life

Studies have consistently indicated that blacks report lower rates of depression than whites. This study examined the association between religion and depression and whether religion explained lower rates of depression among blacks compared to whites. Data were drawn from the National Survey of American Life, a multi-ethnic sample of African Americans, Caribbean Blacks, and non-Hispanic whites (n = 6,082). African Americans and Caribbean Blacks reported higher mean levels of subjective religiosity than whites, but there were no significant differences in levels of church attendance. African Americans (OR 0.54; CI 0.45-0.65) and Caribbean Blacks (OR 0.66; CI 0.48-0.91) reported significantly lower odds of depression than whites. Differences in subjective religiosity and church attendance did not account for the association between major depression and African American and Caribbean Black race/ethnicity relative to whites. More research is needed to examine whether there are other factors that could protect against the development of depression.

Technology-Based Innovations in Child Maltreatment Prevention Programs: Examples from SafeCare®

Each year, hundreds of thousands of children in the U.S. are victims of child maltreatment. Experts recommend behavioral, skill-based parent training programs as a strategy for the prevention of child abuse and neglect. These programs can be enhanced using innovative technology strategies. This paper presents a brief history of the use of technology in SafeCare®, a home visiting program shown to prevent child neglect and physical abuse, and highlights current work that takes a technology-based hybrid approach to SafeCare delivery. With this unique approach, the provider brings a tablet computer to each session, and the parent interacts with the software to receive psychoeducation and modeling of target skills. The provider and parent then work together to practice the targeted skills until mastery is achieved. Initial findings from ongoing research of both of these strategies indicate that they show potential for improving engagement and use of positive parenting skills for parents and ease of implementation for providers. Future directions for technology enhancements in SafeCare are also presented.

Development of the Nursing Community Apgar Questionnaire (NCAQ): a rural nurse recruitment and retention tool

INTRODUCTION

Health professional shortages are a significant issue throughout the USA, particularly in rural communities. Filling nurse vacancies is a costly concern for many critical access hospitals (CAH), which serve as the primary source of health care for rural communities. CAHs and rural communities have strengths and weaknesses that affect their recruitment and retention of rural nurses. The purpose of this study was to develop a tool that rural communities and CAHs can utilize to assess their strengths and weaknesses related to nurse recruitment and retention.

METHODS

The Nursing Community Apgar Questionnaire (NCAQ) was developed based on an extensive literature review, visits to multiple rural sites, and consultations with rural nurses, rural nurse administrators and content experts.

RESULTS

A quantitative interview tool consisting of 50 factors that affect rural nurse recruitment and retention was developed. The tool allows participants to rate each factor in terms of advantage and importance level. The tool also includes three open-ended questions for qualitative analysis.

CONCLUSIONS

The NCAQ was designed to identify rural communities' and CAHs' strengths and challenges related to rural nurse recruitment and retention. The NCAQ will be piloted and a database developed for CAHs to compare their results with those in the database. Furthermore, the NCAQ results may be utilized to prioritize resource allocation and tailor rural nurse recruitment and retention efforts to highlight a community's strengths. The NCAQ will function as a useful real-time tool for CAHs looking to assess and improve their rural nurse recruitment and retention practices and compare their results with those of their peers. Longitudinal results will allow CAHs and their communities to evaluate their progress over time. As the database grows in size, state, regional, and national results can be compared, trends may be discovered and best practices identified.

RPTPζ/phosphacan is abnormally glycosylated in a model of muscle-eye-brain disease lacking functional POMGnT1

Congenital muscular dystrophies (CMDs) with associated brain abnormalities are a group of disorders characterized by muscular dystrophy and brain and eye abnormalities that are frequently caused by mutations in known or putative glycotransferases involved in protein O-mannosyl glycosylation. Previous work identified α-dystroglycan as the major substrate for O-mannosylation and its altered glycosylation the major cause of these disorders. However, work from several labs indicated that other proteins in the brain are also O-mannosylated and therefore could contribute to CMD pathology in patients with mutations in the protein O-mannosylation pathway, however few of these proteins have been identified and fully characterized in CMDs. In this study we identify receptor protein tyrosine phosphatase ζ (RPTPζ) and its secreted variant, phosphacan, as another potentially important substrate for protein O-mannosylation in the brain. Using a mouse model of muscle-eye-brain disease lacking functional protein O-mannose β-1,2-N-acetylglucosaminyltransferase (POMGnT1), we show that RPTPζ/phosphacan is shifted to a lower molecular weight and distinct carbohydrate epitopes normally detected on the protein are either absent or substantially reduced, including Human Natural Killer-1 (HNK-1) reactivity. The spatial and temporal expression patterns of these O-mannosylated forms of RPTPζ/phosphacan and its hypoglycosylation and loss of HNK-1 glycan epitopes in POMGnT1 knockouts are suggestive of a role in the neural phenotypes observed in patients and animal models of CMDs.

Idaho rural family physician workforce study: the Community Apgar Questionnaire

CONTEXT

Community factors of varied importance help determine the success of achieving and maintaining a physician workforce. The purpose of this study was to develop an evaluation instrument (Community Apgar Questioinnaire) useful to rural Idaho communities' in their assessment of the assets and capabilities related to physician recruitment and retention.

METHODS

A quantitative scoring interview instrument was developed based on a literature review, site visits and discussions with rural physicians and hospital administrators. A total of 11 rural Idaho communities differing in geography and other known variables were selected, some identified historically to have more success in recruitment and retention (α communities) and some historically noted to have more challenges (β comunities). In each community, the administrator of the hospital and the physician with recruiting responsibilities participated individually in a structured interview.

RESULTS

A total of 11 physicians and 11 CEOs participated in the study. Differences were found across and within classes of factors associated with success in physician recruitment and retention where alpha communities scored higher on Community Apgar Questionnaire metrics. Some differences were noted by respondent class. Cumulative mean Community Apgar scores are higher in communities that have historically better track records in recruitment and retention.

CONCLUSION

The Community Apgar Questionnaire seems to discriminate between communities with differing assets and capabilities, based on historical community-specific workforce trends. This assessment may allow for identification of both modifiable and non-modifiable factors and also may suggest which factors are most important for a community with limited available resources to address.

Analysis of molecular markers for metamorphic competency and their response to starvation or feeding in the mosquito, Aedes aegypti (Diptera: Culicidae)

The nutritional condition of fourth instar larvae of the yellow fever mosquito, Aedes aegypti, governs female longevity and egg production, both are key determinants of pathogen transmission. As well, nutrition provisions larval growth and development and attains its greatest pace in the last larval instar in preparation for metamorphosis to an adult. These developmental processes are regulated by a complex endocrine interplay of juvenile hormone, neuropeptides, and ecdysteroids that is nutrition sensitive. We previously determined that feeding for only 24h post-ecdysis was sufficient for fourth instar Ae. aegypti larvae to reach critical weight and accumulate sufficient nutritional stores to commit to metamorphosis. To understand the genetic basis of metamorphic commitment in Ae. aegypti, we profiled the expression of 16 genes known to be involved in the endocrine and nutritional regulation of insect metamorphosis in two ways. The first set is a developmental profile from the beginning of the fourth instar to early pupae, and the second set is for fourth instars starved or fed for up to 36 h. By comparing the two sets, we found that seven of the genes (AaegCYP302, AaegJHE43357, AaegBrCZ4, AaegCPF1-2, AaegCPR-7, AaegPpl, and AaegSlif) were expressed during metamorphic commitment in fourth instars and in fed but not starved larvae. Based on these results, the seven genes alone or in combination may serve as molecular indicators of nutritional and metamorphic status of fourth instar Ae. aegypti larvae and possibly other mosquito species in field and laboratory studies to gauge sub-lethal effects of novel and traditional cultural or chemical controls.

Implicit Delegation of Responsibility

In everyday life, people often exert self-control not only for their own sake but also for the sake of close others. Here, the authors examine the specific case of joint self-control—when multiple people must simultaneously exert self-control for mutual success—in the context of close relationships. The authors test the hypothesis that people use situational cues to determine if one member of the relationship bears more responsibility for exerting self-control than the other. In this article, the authors test the specific cue of past behavior and find in two studies that participants who exert self-control on behalf of the relationship on a preliminary task continue to exert self-control on behalf of the relationship on a secondary task compared to those who exerted less self-control on the preliminary task. The authors explain these results by focusing on the role that expectations about behaviors play in contributing effort to a difficult or unpleasant task.

High-prevalence Borrelia miyamotoi infection among [corrected] wild turkeys (Meleagris gallopavo) in Tennessee

During spring and fall 2009, 60 wild turkeys (Meleagris gallopavo) harvested by Tennessee hunters were surveyed for Borrelia spp. by sampling their blood, tissue, and attached ticks. In both seasons, 70% of turkeys were infested with juvenile Amblyomma americanum; one spring turkey hosted an adult female Ixodes brunneus. Polymerase chain reaction assays followed by DNA sequencing indicated that 58% of the turkeys were positive for the spirochete Borrelia miyamotoi, with tissue testing positive more frequently than blood (P = 0.015). Sequencing of the 16S-23S rRNA intergenic spacer indicated > or = 99% similarity to previously published sequences of the North American strain of this spirochete. Positive turkeys were present in both seasons and from all seven middle Tennessee counties sampled. No ticks from the turkeys tested positive for any Borrelia spp. This is the first report of B. miyamotoi in birds; the transmission pathways and epidemiological significance of this high-prevalence spirochetal infection remain uncertain.

Overexpression and altered glycosylation of MUC1 in malignant mesothelioma

Current interest in the MUC1/EMA mucin relates to its role in malignancy, and its potential as a therapeutic target. MUC1/EMA expression has been observed in the majority of epithelioid mesotheliomas. However, little is known of the characteristics of MUC1/EMA in mesothelioma. Herein, we studied the cell surface and soluble expression of the MUC1/EMA glycoprotein, and determined the mRNA and genomic expression profiles in mesothelioma. We found that the anti-MUC1 antibody, E29, was the most diagnostically useful of seven antibody clones examined with a sensitivity of 84% (16 out of 19 cases) and no false positive results. MUC1 mRNA expression was significantly higher in mesothelioma samples than in benign mesothelial cells. No amplification of the MUC1 gene was observed by FISH. Seven of 9 mesothelioma samples expressed MUC1-secreted mRNA isoform in addition to the archetypal MUC1/transmembrane form. CA15.3 (soluble MUC1) levels were significantly higher in the serum of mesothelioma patients than in healthy controls but were not significantly different to levels in patients with benign asbestos-related disease. CA15-3 in effusions could differentiate malignant from benign effusions but were not specific for mesothelioma. Thus, as in other cancers, alterations in MUC1 biology occur in mesothelioma and these results suggest that specific MUC1 characteristics may be useful for mesothelioma diagnosis and should also be investigated as a potential therapeutic target.