Uncovering phantom shocks in cardiac patients with an implantable cardioverter defibrillator

Background: Implantable cardioverter defibrillator recipients sometimes report “phantom shocks” (PSs), defined as a reported shock lacking objective evidence. The aim of this study was to describe the subjective experience of PSs and their psychosocial correlates using a mixed methods approach. Methods: PS participants were matched on sex and age with individuals who received objective shocks only (OSO). Participants were interviewed and completed measures of posttraumatic stress disorder (PTSD Checklist—Civilian Version), depression and anxiety (Hospital Anxiety and Depression Scale), disease-specific distress (Cardiac Anxiety Questionnaire—CAQ), and social desirability (Socially Desirable Response Set—SDRS). Interviews were analyzed using interpretative phenomenological analysis (IPA). Results: Seventeen male patients participated (PS: n = 9; OSO: n = 8). Three themes emerged from IPA: (1) PS as a somatic experience, (2) the emotional impact of PSs, and (3) searching for meaning. Quantitative analyses showed that both groups exhibited elevated trauma and anxiety levels. Effect size differences (ESD) suggested a medium ESD on depression (P = 0.176, ηp 2 = 0.118) and PTSD (avoidance: P = 0.383, ηp 2 = 0.055, numbing: P = 0.311, ηp 2 = 0.068), and a large ESD on SDRS (P = 0.081, ηp 2 = 0.189), where PS participants, comparatively, exhibited elevated levels. A medium ESD was detected on CAQ-fear (P = 0.237, ηp 2 = 0.092) where OSO participants exhibited greater heart-focused worry. Conclusion: The qualitative and quantitative findings of this mixed method study show convergence in terms of the emotional factors associated with the experience of PSs. PSs are often reported to be indistinguishable from objective shocks, evoking alarm, frustration, and confusion, forcing the individual to face the uncertainties of what to them is a novel and confusing experience. (PACE 2013; 36:673–683)This study has not been funded by any source. AB was supported by an Ontario Graduate Scholarship. Dr. Kovacs has received speaking engagement honoraria from Medtronic Inc. Dr. Katz is supported by the Canadian Institutes of Health Research Canada Research Chair in Health Psychology. This paper is derived, in part, from the first author’s Master’s thesis

Self-efficacy as a predictor of patient-reported outcomes in adults with congenital heart disease

OBJECTIVE: Self-efficacy is a known predictor of patient-reported outcomes in individuals with acquired diseases. With an overall objective of better understanding patient-reported outcomes in adults with congenital heart disease, this study aimed to: (i) assess self-efficacy in adults with congenital heart disease, (ii) explore potential demographic and medical correlates of self-efficacy and (iii) determine whether self-efficacy explains additional variance in patient-reported outcomes above and beyond known predictors. METHODS: As part of a large cross-sectional international multi-site study (APPROACH-IS), we enrolled 454 adults (median age 32 years, range: 18-81) with congenital heart disease in two tertiary care centres in Canada and Switzerland. Self-efficacy was measured using the General Self-Efficacy (GSE) scale, which produces a total score ranging from 10 to 40. Variance in the following patient-reported outcomes was assessed: perceived health status, psychological functioning, health behaviours and quality of life. Hierarchical multivariable linear regression analysis was performed. RESULTS: Patients' mean GSE score was 30.1 ± 3.3 (range: 10-40). Lower GSE was associated with female sex ( p = 0.025), not having a job ( p = 0.001) and poorer functional class ( p = 0.048). GSE positively predicted health status and quality of life, and negatively predicted symptoms of anxiety and depression, with an additional explained variance up to 13.6%. No associations between self-efficacy and health behaviours were found. CONCLUSIONS: GSE adds considerably to our understanding of patient-reported outcomes in adults with congenital heart disease. Given that self-efficacy is a modifiable psychosocial factor, it may be an important focus for interventions targeting congenital heart disease patients' well-being

Patient-reported outcomes in the aging population of adults with congenital heart disease: results from APPROACH-IS.

The congenital heart disease (CHD) population now comprises an increasing number of older persons in their 6th decade of life and beyond. We cross-sectionally evaluated patient-reported outcomes (PROs) in persons with CHD aged 60 years or older, and contrasted these with PROs of younger patients aged 40-59 years and 18-39 years. Adjusted for demographic and medical characteristics, patients ≥60 years had a lower Physical Component Summary, higher Mental Component Summary, and lower anxiety (Hospital Anxiety and Depression Scale-Anxiety) scores than patients in the two younger categories. For satisfaction with life, older persons had a higher score than patients aged 40-59 years. Registration: ClinicalTrials.gov NCT02150603

Hundreds of variants clustered in genomic loci and biological pathways affect human height

Most common human traits and diseases have a polygenic pattern of inheritance: DNA sequence variants at many genetic loci influence the phenotype. Genome-wide association (GWA) studies have identified more than 600 variants associated with human traits, but these typically explain small fractions of phenotypic variation, raising questions about the use of further studies. Here, using 183,727 individuals, we show that hundreds of genetic variants, in at least 180 loci, influence adult height, a highly heritable and classic polygenic trait. The large number of loci reveals patterns with important implications for genetic studies of common human diseases and traits. First, the 180 loci are not random, but instead are enriched for genes that are connected in biological pathways (P = 0.016) and that underlie skeletal growth defects (P < 0.001). Second, the likely causal gene is often located near the most strongly associated variant: in 13 of 21 loci containing a known skeletal growth gene, that gene was closest to the associated variant. Third, at least 19 loci have multiple independently associated variants, suggesting that allelic heterogeneity is a frequent feature of polygenic traits, that comprehensive explorations of already-discovered loci should discover additional variants and that an appreciable fraction of associated loci may have been identified. Fourth, associated variants are enriched for likely functional effects on genes, being over-represented among variants that alter amino-acid structure of proteins and expression levels of nearby genes. Our data explain approximately 10% of the phenotypic variation in height, and we estimate that unidentified common variants of similar effect sizes would increase this figure to approximately 16% of phenotypic variation (approximately 20% of heritable variation). Although additional approaches are needed to dissect the genetic architecture of polygenic human traits fully, our findings indicate that GWA studies can identify large numbers of loci that implicate biologically relevant genes and pathways.

Phenotypes of adults with congenital heart disease around the globe: a cluster analysis

Objective To derive cluster analysis-based groupings for adults with congenital heart disease (ACHD) when it comes to perceived health, psychological functioning, health behaviours and quality of life (QoL). Methods This study was part of a larger worldwide multicentre study called APPROACH-IS; a cross sectional study which recruited 4028 patients (2013–2015) from 15 participating countries. A hierarchical cluster analysis was performed using Ward's method in order to group patients with similar psychological characteristics, which were defined by taking into consideration the scores of the following tests: Sense Of Coherence, Health Behavior Scale (physical exercise score), Hospital Anxiety Depression Scale, Illness Perception Questionnaire, Satisfaction with Life Scale and the Visual Analogue Scale scores of the EQ-5D perceived health scale and a linear analogue scale (0–100) measuring QoL. Results 3768 patients with complete data were divided into 3 clusters. The first and second clusters represented 89.6% of patients in the analysis who reported a good health perception, QoL, psychological functioning and the greatest amount of exercise. Patients in the third cluster reported substantially lower scores in all PROs. This cluster was characterised by a significantly higher proportion of females, a higher average age the lowest education level, more complex forms of congenital heart disease and more medical comorbidities. Conclusions This study suggests that certain demographic and clinical characteristics may be linked to less favourable health perception, quality of life, psychological functioning, and health behaviours in ACHD. This information may be used to improve psychosocial screening and the timely provision of psychosocial care

Genome-wide association and functional follow-up reveals new loci for kidney function

Chronic kidney disease (CKD) is an important public health problem with a genetic component. We performed genome-wide association studies in up to 130,600 European ancestry participants overall, and stratified for key CKD risk factors. We uncovered 6 new loci in association with estimated glomerular filtration rate (eGFR), the primary clinical measure of CKD, in or near MPPED2, DDX1, SLC47A1, CDK12, CASP9, and INO80. Morpholino knockdown of mpped2 and casp9 in zebrafish embryos revealed podocyte and tubular abnormalities with altered dextran clearance, suggesting a role for these genes in renal function. By providing new insights into genes that regulate renal function, these results could further our understanding of the pathogenesis of CKD

Integration of genome-wide association studies with biological knowledge identifies six novel genes related to kidney function

In conducting genome-wide association studies (GWAS), analytical approaches leveraging biological information may further understanding of the pathophysiology of clinical traits. To discover novel associations with estimated glomerular filtration rate (eGFR), a measure of kidney function, we developed a strategy for integrating prior biological knowledge into the existing GWAS data for eGFR from the CKDGen Consortium. Our strategy focuses on single nucleotide polymorphism (SNPs) in genes that are connected by functional evidence, determined by literature mining and gene ontology (GO) hierarchies, to genes near previously validated eGFR associations. It then requires association thresholds consistent with multiple testing, and finally evaluates novel candidates by independent replication. Among the samples of European ancestry, we identified a genome-wide significant SNP in FBXL20 (P = 5.6 × 10−9) in meta-analysis of all available data, and additional SNPs at the INHBC, LRP2, PLEKHA1, SLC3A2 and SLC7A6 genes meeting multiple-testing corrected significance for replication and overall P-values of 4.5 × 10−4-2.2 × 10−7. Neither the novel PLEKHA1 nor FBXL20 associations, both further supported by association with eGFR among African Americans and with transcript abundance, would have been implicated by eGFR candidate gene approaches. LRP2, encoding the megalin receptor, was identified through connection with the previously known eGFR gene DAB2 and extends understanding of the megalin system in kidney function. These findings highlight integration of existing genome-wide association data with independent biological knowledge to uncover novel candidate eGFR associations, including candidates lacking known connections to kidney-specific pathways. The strategy may also be applicable to other clinical phenotypes, although more testing will be needed to assess its potential for discovery in genera

Genome-wide association meta-analyses and fine-mapping elucidate pathways influencing albuminuria

Abstract: Increased levels of the urinary albumin-to-creatinine ratio (UACR) are associated with higher risk of kidney disease progression and cardiovascular events, but underlying mechanisms are incompletely understood. Here, we conduct trans-ethnic (n = 564,257) and European-ancestry specific meta-analyses of genome-wide association studies of UACR, including ancestry- and diabetes-specific analyses, and identify 68 UACR-associated loci. Genetic correlation analyses and risk score associations in an independent electronic medical records database (n = 192,868) reveal connections with proteinuria, hyperlipidemia, gout, and hypertension. Fine-mapping and trans-Omics analyses with gene expression in 47 tissues and plasma protein levels implicate genes potentially operating through differential expression in kidney (including TGFB1, MUC1, PRKCI, and OAF), and allow coupling of UACR associations to altered plasma OAF concentrations. Knockdown of OAF and PRKCI orthologs in Drosophila nephrocytes reduces albumin endocytosis. Silencing fly PRKCI further impairs slit diaphragm formation. These results generate a priority list of genes and pathways for translational research to reduce albuminuria