Sibling risk of hospitalization for heart failure – A nationwide study

Familial clustering of unexplained heart failure - A Danish nationwide cohort study

AIMS

To determine whether a family history of unexplained heart failure (HF) in first-degree relatives (children or sibling) increases the rate of unexplained HF.

METHODS AND RESULTS

Using Danish nationwide registry data (1978-2017), we identified patients (probands) diagnosed with first unexplained HF (HF without any known comorbidities) in Denmark, and their first-degree relatives. All first-degree relatives were followed from the HF date of the proband and until an event of unexplained HF, exclusion diagnosis, death, emigration, or study end, whichever occurred first. Using the general population as a reference, we calculated adjusted standardized incidence ratios (SIR) of unexplained HF in the three groups of relatives using Poisson regression models. We identified 55,110 first-degree relatives to individuals previously diagnosed with unexplained HF. Having a family history was associated with a significantly increased unexplained HF rate of 2.59 (95%CI 2.29-2.93). The estimate was higher among siblings (SIR 6.67 [95%CI 4.69-9.48]). Noteworthy, the rate of HF increased for all first-degree relatives when the proband was diagnosed with HF in a young age (≤50 years, SIR of 7.23 [95%CI 5.40-9.68]) and having >1 proband (SIR of 5.28 [95%CI 2.75-10.14]). The highest estimate of HF was observed if the proband was ≤40 years at diagnosis (13.17 [95%CI 8.90-19.49].

CONCLUSION

A family history of unexplained HF was associated with a two-fold increased rate of unexplained HF among first-degree relatives. The relative rate was increased when the proband was diagnosed at a young age. These data suggest that screening families of unexplained HF with onset below 50 years is indicated.

Lipoprotein(a), family history of cardiovascular disease, and incidence of heart failure

Lipoprotein(a) (Lp(a)) is a largely genetically determined biomarker for cardiovascular disease (CVD), while its potential interplay with family history (FHx) of CVD, a measure of both genetic and environmental exposures, remains unclear. We examined the associations of Lp(a) in terms of circulating concentration or polygenetic risk score (PRS), and FHx of CVD with risk of incident heart failure (HF). Included were 299,158 adults from the UK Biobank without known HF and CVD at baseline. Hazards ratios (HRs) and 95% Cls were estimated by Cox regression models adjusted for traditional risk factors defined by the Atherosclerosis Risk in Communities study HF risk score. During the 11.8-year follow-up, 5,502 incidents of HF occurred. Higher levels of circulating Lp(a), Lp(a) PRS, and positive FHx of CVD were associated with higher risks of HF. Compared with individuals who had lower circulating Lp(a) and no FHx, HRs (95% CIs) of HF were 1.36 (1.25, 1.49), 1.31 (1.19, 1.43), and 1.42 (1.22, 1.67) for those with higher Lp(a) and a positive history of CVD for all family members, parents, and siblings, respectively; similar results were observed by using Lp(a) PRS. The risk estimates for HF associated with elevated Lp(a) and positive FHx were attenuated after excluding those with incident myocardial infarction (MI) during follow-up. Lp(a) and FHx of CVD were independent risk factors for incident HF, and the highest risk of HF was observed among individuals with both risk factors. The association may be partly mediated by myocardial infarction.

Genetic predisposition study of heart failure and its association with cardiomyopathy

Heart failure (HF) is a clinical condition distinguished by structural and functional defects in the myocardium, which genetic and environmental factors can induce. HF is caused by various genetic factors that are both heterogeneous and complex. The incidence of HF varies depending on the definition and area, but it is calculated to be between 1 and 2% in developed countries. There are several factors associated with the progression of HF, ranging from coronary artery disease to hypertension, of which observed the most common genetic cause to be cardiomyopathy. The main objective of this study is to investigate heart failure and its association with cardiomyopathy with their genetic variants. The selected novel genes that have been linked to human inherited cardiomyopathy play a critical role in the pathogenesis and progression of HF. Research sources collected from the human gene mutation and several databases revealed that numerous genes are linked to cardiomyopathy and thus explained the hereditary influence of such a condition. Our findings support the understanding of the genetics aspect of HF and will provide more accurate evidence of the role of changing disease accuracy. Furthermore, a better knowledge of the molecular pathophysiology of genetically caused HF could contribute to the emergence of personalized therapeutics in future.

RNA-seq driven expression and enrichment analysis to investigate CVD genes with associated phenotypes among high-risk heart failure patients

Background

Heart failure (HF) is one of the most common complications of cardiovascular diseases (CVDs) and among the leading causes of death in the US. Many other CVDs can lead to increased mortality as well. Investigating the genetic epidemiology and susceptibility to CVDs is a central focus of cardiology and biomedical life sciences. Several studies have explored expression of key CVD genes specially in HF, yet new targets and biomarkers for early diagnosis are still missing to support personalized treatment. Lack of gender-specific cardiac biomarker thresholds in men and women may be the reason for CVD underdiagnosis in women, and potentially increased morbidity and mortality as a result, or conversely, an overdiagnosis in men. In this context, it is important to analyze the expression and enrichment of genes with associated phenotypes and disease-causing variants among high-risk CVD populations.

Methods

We performed RNA sequencing focusing on key CVD genes with a great number of genetic associations to HF. Peripheral blood samples were collected from a broad age range of adult male and female CVD patients. These patients were clinically diagnosed with CVDs and CMS/HCC HF, as well as including cardiomyopathy, hypertension, obesity, diabetes, asthma, high cholesterol, hernia, chronic kidney, joint pain, dizziness and giddiness, osteopenia of multiple sites, chest pain, osteoarthritis, and other diseases.

Results

We report RNA-seq driven case–control study to analyze patterns of expression in genes and differentiating the pathways, which differ between healthy and diseased patients. Our in-depth gene expression and enrichment analysis of RNA-seq data from patients with mostly HF and other CVDs on differentially expressed genes and CVD annotated genes revealed 4,885 differentially expressed genes (DEGs) and regulation of 41 genes known for HF and 23 genes related to other CVDs, with 15 DEGs as significantly expressed including four genes already known (FLNA, CST3, LGALS3, and HBA1) for HF and CVDs with the enrichment of many pathways. Furthermore, gender and ethnic group specific analysis showed shared and unique genes between the genders, and among different races. Broadening the scope of the results in clinical settings, we have linked the CVD genes with ICD codes.

Conclusions

Many pathways were found to be enriched, and gender-specific analysis showed shared and unique genes between the genders. Additional testing of these genes may lead to the development of new clinical tools to improve diagnosis and prognosis of CVD patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40246-021-00367-8.

Towards precision medicine in heart failure

The number of therapies for heart failure (HF) with reduced ejection fraction has nearly doubled in the past decade. In addition, new therapies for HF caused by hypertrophic and infiltrative disease are emerging rapidly. Indeed, we are on the verge of a new era in HF in which insights into the biology of myocardial disease can be matched to an understanding of the genetic predisposition in an individual patient to inform precision approaches to therapy. In this Review, we summarize the biology of HF, emphasizing the causal relationships between genetic contributors and traditional structure-based remodelling outcomes, and highlight the mechanisms of action of traditional and novel therapeutics. We discuss the latest advances in our understanding of both the Mendelian genetics of cardiomyopathy and the complex genetics of the clinical syndrome presenting as HF. In the phenotypic domain, we discuss applications of machine learning for the subcategorization of HF in ways that might inform rational prescribing of medications. We aim to bridge the gap between the biology of the failing heart, its diverse clinical presentations and the range of medications that we can now use to treat it. We present a roadmap for the future of precision medicine in HF.

Modification effect of ideal cardiovascular health metrics on genetic association with incident heart failure in the China Kadoorie Biobank and the UK Biobank

BACKGROUND

Both genetic and cardiovascular factors contribute to the risk of developing heart failure (HF), but whether idea cardiovascular health metrics (ICVHMs) offset the genetic association with incident HF remains unclear.

OBJECTIVES

To investigate the genetic association with incident HF as well as the modification effect of ICVHMs on such genetic association in Chinese and British populations.

METHODS

An ICVHMs based on smoking, drinking, physical activity, diets, body mass index, waist circumference, blood pressure, blood glucose, and blood lipids, and a polygenic risk score (PRS) for HF were constructed in the China Kadoorie Biobank (CKB) of 96,014 participants and UK Biobank (UKB) of 335,782 participants which were free from HF and severe chronic diseases at baseline.

RESULTS

During the median follow-up of 11.38 and 8.73 years, 1451 and 3169 incident HF events were documented in CKB and UKB, respectively. HF risk increased monotonically with the increase of PRS per standard deviation (CKB: hazard ratio [HR], 1.19; 95% confidence interval [CI], 1.07, 1.32; UKB: 1.07; 1.03, 1.11; P for trend < 0.001). Each point increase in ICVHMs was associated with 15% and 20% lower risk of incident HF in CKB (0.85; 0.81, 0.90) and UKB (0.80; 0.77, 0.82), respectively. Compared with unfavorable ICVHMs, favorable ICVHMs was associated with a lower HF risk, with 0.71 (0.44, 1.15), 0.41 (0.22, 0.77), and 0.48 (0.30, 0.77) in the low, intermediate, and high genetic risk in CKB and 0.34 (0.26, 0.44), 0.32 (0.25, 0.41), and 0.37 (0.28, 0.47) in UKB (P for multiplicative interaction > 0.05). Participants with low genetic risk and favorable ICVHMs, as compared with high genetic risk and unfavorable ICVHMs, had 56~72% lower risk of HF (CKB 0.44; 0.28, 0.70; UKB 0.28; 0.22, 0.37). No additive interaction between PRS and ICVHMs was observed (relative excess risk due to interaction was 0.05 [-0.22, 0.33] in CKB and 0.04 [-0.14, 0.22] in UKB).

CONCLUSIONS

In CKB and UKB, genetic risk and ICVHMs were independently associated with the risk of incident HF, which suggested that adherence to favorable cardiovascular health status was associated with a lower HF risk among participants with all gradients of genetic risk.

Sibling history is associated with heart failure after a first myocardial infarction

Objective

Morbidity and mortality due to heart failure (HF) as a complication of myocardial infarction (MI) is high, and remains among the leading causes of death and hospitalisation. This study investigated the association between family history of MI with or without HF, and the risk of developing HF after first MI.

Methods

Through nationwide registries, we identified all individuals aged 18-50 years hospitalised with first MI from 1997 to 2016 in Denmark. We identified 13 810 patients with MI, and the cohort was followed until HF diagnosis, second MI, 3 years after index MI, emigration, death or the end of 2016, whichever occurred first. HRs were estimated by Cox hazard regression models adjusted for sex, age, calendar year and comorbidities (reference: patients with no family history of MI).

Results

After adjustment, we observed an increased risk of MI-induced HF for those having a sibling with MI with HF (HR 2.05, 95% CI 1.02 to 4.12). Those having a sibling with MI without HF also had a significant, but lower increased risk of HF (HR 1.39, 95% CI 1.05 to 1.84). Parental history of MI with or without HF was not associated with HF.

Conclusion

In this nationwide cohort, sibling history of MI with or without HF was associated with increased risk of HF after first MI, while a parental family history was not, suggesting that shared environmental factors may predominate in the determination of risk for developing HF.

Integrated Multiomics Approach to Identify Genetic Underpinnings of Heart Failure and Its Echocardiographic Precursors

Background:

Heart failure (HF) may arise from alterations in metabolic, structural, and signaling pathways, but its genetic architecture is incompletely understood. To elucidate potential genetic contributors to cardiac remodeling and HF, we integrated genome-wide single-nucleotide polymorphisms, gene expression, and DNA methylation using a transomics analytical approach.

Methods:

We used robust rank aggregation (where the position of a certain gene in a rank order list [based on statistical significance level] is tested against a randomly shuffled rank order list) to derive an integrative transomic score for each annotated gene associated with a HF trait.

Results:

We evaluated ≤8372 FHS (Framingham Heart Study) participants (54% women; mean age, 55±17 years). Of these, 62 (0.7%) and 35 (0.4%) had prevalent HF with reduced ejection fraction and HF with preserved left ventricular ejection fraction, respectively. During a mean follow-up of 8.5 years (minimum–maximum, 0.005–18.6 years), 223 (2.7%) and 234 (2.8%) individuals developed incident HF with reduced ejection fraction and HF with reduced ejection fraction, respectively. Top genes included MMP20 and MTSS1 (promotes actin assembly at intercellular junctions) for left ventricular systolic function; ITGA9 (receptor for VCAM1 [vascular cell protein 1]) and C5 for left ventricular remodeling; NUP210 (expressed during myogenic differentiation) and ANK1 (cytoskeletal protein) for diastolic function; TSPAN16 and RAB11FIP3 (involved in regulation of actin cytoskeleton) for prevalent HF with reduced ejection fraction; ANKRD13D and TRIM69 for incident HF with reduced ejection fraction; HPCAL1 and PTTG1IP for prevalent HF with reduced ejection fraction; and ZNF146 (close to the COX7A1 enzyme) and ZFP3 (close to SLC52A1 —the riboflavin transporter) for incident HF with reduced ejection fraction. We tested the HF-related top single-nucleotide polymorphisms in the UK biobank, where rs77059055 in TPM1 (minor allele frequency, 0.023; odds ratio, 0.83; P =0.002) remained statistically significant upon Bonferroni correction.

Conclusions:

Our integrative transomics approach offers insights into potential molecular and genetic contributors to HF and its precursors. Although several of our candidate genes have been implicated in HF in animal models, independent replication is warranted.

Familial Mortality Risks in Patients With Heart Failure-A Swedish Sibling Study

Background

The influence of familial factors on the prognosis of heart failure (HF) is unknown. This nationwide follow‐up study aimed to determine familial mortality risks of HF among Swedish siblings hospitalized for HF.

Methods and Results

We linked several Swedish nationwide registers for individuals aged 0 to 80 years. The study population consisted of 373 people hospitalized for HF for the first time between 2000 and 2012 with 1 proband sibling previously hospitalized for HF for the first time between 2000 and 2007. Families with congenital heart disease were excluded. Familial hazard ratios (HRs) for mortality after first HF hospitalization were determined with Cox regression. The influence of proband survival was categorized as short survival (<5 years) or long survival (≥5 years) and determined continuously for the initial 5 years of proband survival. Adjustments were made for age, sex, time period, and common HF comorbidities. Short proband survival was associated with a HR of 2.02 (95% confidence interval, 1.32–3.09) for overall mortality. This HR was 2.35 (95% confidence interval, 1.18–4.67) in patients without preceding coronary heart disease, whereas patients with ischemic HF had an HR of 1.84 (95% confidence interval, 1.05–3.23). For each year of proband survival, the risk of death decreased, with a HR of 0.86 (95% confidence interval, 0.77–0.98).

Conclusions

Our results suggest that family history of poor survival in specific relation to HF is an important risk factor for death in HF patients. Additional studies are needed to characterize the molecular underpinnings and detailed phenotypic characteristics of such patients.

A Swedish Nationwide Adoption Study of the Heritability of Heart Failure

Importance

Heart failure (HF) aggregates in families, but the heritability of HF has not been determined. Discerning the genetic and environmental contributions to HF risk is important to further helping to identify individuals at risk. Adoption studies may establish the genetic contribution to HF.

Objective

This nationwide adoption study aimed to determine the heritability of HF.

Design, Setting, and Participants

This case-control study and cohort study design used logistic regression for calculating risks of HF in adoptees. Adoptees who were born in Sweden between 1942 and 1990 were linked to their adoptive parents and biological parents. The Swedish Multi-Generation Register was linked to the Swedish Patient Register for information on hospital inpatient and outpatient admissions and to the Swedish Cause of Death Register for the period 1964 through 2015. Heritability (h2 with a standard error) for HF was determined both with Falconer regression and with tetrachoric correlation. Data analysis was completed from July 2017 to April 2018.

Exposures

Heart failure in biological parents and/or adoptive parents.

Main Outcomes and Measures

Heritability; risk of HF, expressed as odds ratios.

Results

A total of 21 643 adoptees were included (of whom 10 626 [49.1%] were female), as well as 35 016 adoptive parents (14 872 [42.5%] female) and 43 286 biological parents (21 643 [50.0%] female). There were 194 cases of HF in adoptees, 3972 cases of HF in adoptive parents, and 3657 cases of HF in biological parents. The cohort study odds ratio (OR) for heart failure was 1.45 in adoptees (95% CI, 1.04-2.03) for biological parents with HF, compared with those without an affected biological parent. If cardiomyopathies were excluded, this OR was 1.58 (95% CI, 1.03-2.42). The corresponding OR associated with an affected adoptive parent were nonsignificant, both with cardiomyopathies included (OR, 0.83 [95% CI, 0.57-1.20]) and with cardiomyopathies excluded (OR, 0.79 [95% CI, 0.49-1.29]). The heritability of HF per Falconer regression (h2) was 26% (SE, 14%). With exclusion of cardiomyopathies the heritability using Falconer regression was 34% (SE, 18%).

Conclusions and Relevance

Heart failure in a biological parent is an HF risk factor that is worth clinical consideration. The increased heritability of HF suggests that genetic factors are important in HF pathogenesis.

Mortality risks associated with sibling heart failure

BACKGROUND

The mortality in individuals with a family history of heart failure (HF) has not been determined. This nationwide sib-pair study aimed to determine mortality in individuals with a sibling affected with HF.

METHODS

Sib-pairs were linked using the Swedish Multi-Generation Register, the Hospital Discharge Register and the Cause of Death Register for the period 1987-2012. Families with cardiomyopathy or congenital heart disease were excluded. Mortality hazard ratios (HRs) were calculated for siblings of individuals who had been diagnosed with HF compared with siblings of individuals unaffected by HF as the reference group. Similar analyses were made for spouses. HRs were determined for overall mortality, cardiovascular mortality, and death of unknown cause.

RESULTS

Among siblings, the adjusted HR for overall mortality was 1.21 (95% CI 1.18-1.25). This risk remained (HR = 1.19, 95% CI 1.15-1.23) also among subjects without HF themselves. The adjusted HRs for cardiovascular mortality and death of unknown cause were 1.39 (95% CI 1.32-1.45) and 1.58 (95% CI 1.29-1.95), respectively. The mortality risk associations with spousal HF were all minimal, with an overall mortality HR of 1.02 (1.01-1.02). Early sibling age of onset of HF < 50 years was associated with higher HRs for overall mortality, cardiovascular mortality, and death of unknown cause, 1.33 (1.27-1.41), 1.54 (1.40-1.68) and 1.84 (1.27-2.67), respectively.

CONCLUSIONS

Sibling HF, especially early-onset HF, is associated with increased mortality. The low risk in spouses suggests genetic factors might be of importance. Screening for HF, and cardiovascular disease in general, in these individuals may be warranted.

Quantitative trait loci associated with angiotensin II and high-salt diet induced acute decompensated heart failure in Balb/CJ mice

Genetic background of different mouse strains determines their susceptibility to disease. We have previously shown that Balb/CJ and C57BL/6J mice develop cardiac hypertrophy to the same degree when treated with a combination of angiotensin II and high-salt diet (ANG II+Salt), but only Balb/CJ show impaired cardiac function associated with edema development and substantial mortality. We hypothesized that the different response to ANG II+Salt is due to the different genetic backgrounds of Balb/CJ and C57BL/6J. To address this we performed quantitative trait locus (QTL) mapping of second filial generation (F2) of mice derived from a backcross between Balb/CJ and first filial generation (F1) of mice. Cardiac function was measured with echocardiography, glomerular filtration rate using FITC-inulin clearance, fluid and electrolyte balance in metabolic cages, and blood pressure with tail-cuff at baseline and on the fourth day of treatment with ANG II+Salt. A total of nine QTLs were found to be linked to different phenotypes in ANG II+Salt-treated F2 mice. A QTL on chromosome 3 was linked to cardiac output, and a QTL on chromosome 12 was linked to isovolumic relaxation time. QTLs on chromosome 2 and 3 were linked to urine excretion and sodium excretion. Eight genes located at the different QTLs contained coding nonsynonymous SNPs published in the mouse genome database that differ between Balb/CJ and C57BL/6J. In conclusion, ANG II+Salt-induced acute decompensation in Balb/CJ is genetically linked to several QTLs, indicating a multifaceted phenotype. The present study identified potential candidate genes that may represent important pathways in acute decompensated heart failure.

Genetic determinants of heart failure: facts and numbers

The relevance of gene mutations leading to heart diseases and hence heart failure has become evident. The risk for and the course of heart failure depends on genomic variants and mutations underlying the so‐called genetic predisposition. Genetic contribution to heart failure is highly heterogenous and complex. For any patient with a likely inherited heart failure syndrome, genetic counselling is recommended and important. In the last few years, novel sequencing technologies (named next‐generation sequencing – NGS) have dramatically improved the availability of molecular testing, the efficiency of genetic analyses, and moreover reduced the cost for genetic testing. Due to this development, genetic testing has become increasingly accessible and NGS‐based sequencing is now applied in clinical routine diagnostics. One of the most common reasons of heart failure are cardiomyopathies such as the dilated or the hypertrophic cardiomyopathy. Nearly 100 disease‐associated genes have been identified for cardiomyopathies. The knowledge of a pathogenic mutation can be used for genetic counselling, risk and prognosis determination, therapy guidance and hence for a more effective treatment. Besides, family cascade screening for a known familial, pathogenic mutation can lead to an early diagnosis in affected individuals. At that timepoint, a preventative intervention could be used to avoid or delay disease onset or delay disease progression. Understanding the cellular basis of genetic heart failure syndromes in more detail may provide new insights into the molecular biology of physiological and impaired cardiac (cell) function. As our understanding of the molecular and genetic pathophysiology of heart failure will increase, this might help to identify novel therapeutic targets and may lead to the development of new and specific treatment options in patients with heart failure.

Molecular Epidemiology of Heart Failure: Translational Challenges and Opportunities

Heart failure (HF) is the end-stage of all heart disease and arguably constitutes the greatest unmet therapeutic need in cardiovascular medicine today. Classic epidemiological studies have established clinical risk factors for HF, but the cause remains poorly understood in many cases. Biochemical analyses of small case-control series and animal models have described a plethora of molecular characteristics of HF, but a single unifying pathogenic theory is lacking. Heart failure appears to result not only from cardiac overload or injury but also from a complex interplay among genetic, neurohormonal, metabolic, inflammatory, and other biochemical factors acting on the heart. Recent development of robust, high-throughput tools in molecular biology provides opportunity for deep molecular characterization of population-representative cohorts and HF cases (molecular epidemiology), including genome sequencing, profiling of myocardial gene expression and chromatin modifications, plasma composition of proteins and metabolites, and microbiomes. The integration of such detailed information holds promise for improving understanding of HF pathophysiology in humans, identification of therapeutic targets, and definition of disease subgroups beyond the current classification based on ejection fraction which may benefit from improved individual tailoring of therapy. Challenges include: 1) the need for large cohorts with deep, uniform phenotyping; 2) access to the relevant tissues, ideally with repeated sampling to capture dynamic processes; and 3) analytical issues related to integration and analysis of complex datasets. International research consortia have formed to address these challenges and combine datasets, and cohorts with up to 1 million participants are being collected. This paper describes the molecular epidemiology of HF and provides an overview of methods and tissue types and examples of published and ongoing efforts to systematically evaluate molecular determinants of HF in human populations.