The Gly82Ser polymorphism in the receptor for advanced glycation endproducts increases the risk for coronary events in the general population.

The receptor for advanced glycation endproducts (RAGE) has pro-inflammatory and pro-atherogenic effects. Low plasma levels of soluble RAGE (sRAGE), a decoy receptor for RAGE ligands, have been associated with increased risk for major adverse coronary events (MACE) in the general population. We performed a genome-wide association study to identify genetic determinants of plasma sRAGE in 4338 individuals from the cardiovascular arm of the Malmö Diet and Cancer study (MDC-CV). Further, we explored the associations between these genetic variants, incident first-time MACE and mortality in 24,640 unrelated individuals of European ancestry from the MDC cohort. The minor alleles of four single nucleotide polymorphisms (SNPs): rs2070600, rs204993, rs116653040, and rs7306778 were independently associated with lower plasma sRAGE. The minor T (vs. C) allele of rs2070600 was associated with increased risk for MACE [HR 1.13 95% CI (1.02-1.25), P = 0.016]. Neither SNP was associated with mortality. This is the largest study to demonstrate a link between a genetic sRAGE determinant and CV risk. Only rs2070600, which enhances RAGE function by inducing a Gly82Ser polymorphism in the ligand-binding domain, was associated with MACE. The lack of associations with incident MACE for the other sRAGE-lowering SNPs suggests that this functional RAGE modification is central for the observed relationship.

Clinical Evaluation of the Polygenetic Background of Blood Pressure in the Population-Based Setting.

The clinical value of the polygenetic component of blood pressure (BP) is commonly questioned. We evaluated a genetic risk score for BP (BP-GRS858), based on the most recently published genome-wide association studies variants that were significantly associated with either systolic BP or diastolic BP, for prediction of hypertension and cardiovascular end points. The genotyping was performed in 2 urban-based prospective cohorts: the Malmö Diet and Cancer (n=29 295) and the Malmö Preventive Project (n=9367) and a weighted BP-GRS858 based on 858 SNPs was calculated. At baseline, we found a difference of 9.0 mm Hg (systolic BP) and 4.8 mm Hg (diastolic BP) between the top and the bottom quartile of BP-GRS858. In Malmö Preventive Project, the top versus bottom quartile of BP-GRS858 was associated with a doubled risk of incident hypertension (odds ratio, 2.05 [95% CI, 1.75-2.39], P=1.4×10-21), a risk higher than that of body mass index, as evaluated in quartiles. In Malmö Diet and Cancer, significant association was found between the age and sex-adjusted BP-GRS858 and the incidence of total cardiovascular events, stroke, coronary artery disease, heart failure, atrial fibrillation, and total mortality. Most of these associations remained significant after adjusting for traditional risk factors, including hypertension. BP-GRS858 could contribute predictive information regarding future hypertension, with an effect size comparable to other well-known risk factors such as obesity, and predicts cardiovascular events. Given that the exposure to high polygenetic risk starts at birth, we suggest that the BP-GRS858 might be useful to identify children or adolescents who would benefit from early hypertension screening and treatment.

Orthostatic Hypotension and Novel Blood Pressure Associated Gene Variants in Older Adults: Data From the TILDA Study.

Orthostatic hypotension (OH) is associated with increased risk of trauma and cardiovascular events. Recent studies have identified new genetic variants that influence orthostatic blood pressure (BP). The aim of this study was to investigate the associations of candidate gene loci with orthostatic BP responses in older adults. A total of 3,430 participants aged ≥50 years from The Irish Longitudinal Study on Ageing (TILDA) with BP measures and genetic data from 12 single-nucleotide polymorphism (SNP) linked to BP responses were analyzed. Orthostatic BP responses were recorded at each 10 s interval and were defined as OH (SBP drop ≥20 mmHg or DBP drop ≥10 mmHg) at the time-points 40, 90, and 110 s. We defined sustained OH (SOH) as a drop that exceeded consensus BP thresholds for OH at 40, 90, and 110 s after standing. Logistic regression analyses modeled associations between the candidate SNP alleles and OH. We report no significant associations between OH and measured SNPs after correction for multiple comparisons apart from the SNP rs5068 where proportion of the minor allele was significantly different between cases and controls for SOH 40 (p = .002). After adjustment for covariates in a logistic regression, those with the minor G allele (compared to the A allele) had a decreased incidence rate ratio (IRR) for SOH 40 (IRR 0.45, p = .001, 95% CI 0.29-0.72). Only one SNP linked with increased natriuretic peptide concentrations was associated with OH. These results suggest that genetic variants may have a weak impact on OH but needs verification in other population studies.

Polygenetic risk for coronary artery disease increases hospitalization burden and mortality.

BACKGROUND: Coronary artery disease (CAD) is a leading cause of death worldwide and increasing cost for society. Genome wide association studies (GWAS) have identified common variants associated with CAD. Combining single nucleotide polymorphisms (SNPs) into a genetic risk score (GRS) can estimate an individual's genetic burden. OBJECTIVES: To investigate whether GRS for CAD can predict hospitalization and mortality. METHODS: 23,594 individuals without CAD at baseline and with full data for all covariates from the population based prospective study Malmö diet and cancer study were investigated. The association between hospitalizations was calculated by negative binomial regression and risk of mortality was calculated by Cox proportional hazards regression. The GRS was constructed from 50 SNPs. RESULTS: The study population was divided into quintiles according to the value of GRS. During the mean follow-up time of 17.8 years, 17,254 individuals were hospitalized at least once. Individuals in the highest quintile of GRS were hospitalized 10% more often than individuals in the lowest quintile (IRR: 1.10 [95% CI 1.04-1.16], p = 0.001), mainly for cardiovascular reasons (IRR: 1.31 [95% CI 1.20-1.43], p = 5.17 × 10-10). These individuals had highly increased risk of CVD mortality (HR: 1.44 [1.25-1.66], p = 6.56 × 10-7) but not the risk of mortality due to other causes. CONCLUSION: Our results suggest that genetic predisposition for CAD can predict hospitalization burden and mortality, especially due to cardiovascular causes, independently of traditional risk factors. As the risk conferred by the GRS is partially modifiable, our results may help to reduce societal costs, individual suffering and prolong life.

Genetic inactivation of ANGPTL4 improves glucose homeostasis and is associated with reduced risk of diabetes.

Angiopoietin-like 4 (ANGPTL4) is an endogenous inhibitor of lipoprotein lipase that modulates lipid levels, coronary atherosclerosis risk, and nutrient partitioning. We hypothesize that loss of ANGPTL4 function might improve glucose homeostasis and decrease risk of type 2 diabetes (T2D). We investigate protein-altering variants in ANGPTL4 among 58,124 participants in the DiscovEHR human genetics study, with follow-up studies in 82,766 T2D cases and 498,761 controls. Carriers of p.E40K, a variant that abolishes ANGPTL4 ability to inhibit lipoprotein lipase, have lower odds of T2D (odds ratio 0.89, 95% confidence interval 0.85-0.92, p = 6.3 × 10-10), lower fasting glucose, and greater insulin sensitivity. Predicted loss-of-function variants are associated with lower odds of T2D among 32,015 cases and 84,006 controls (odds ratio 0.71, 95% confidence interval 0.49-0.99, p = 0.041). Functional studies in Angptl4-deficient mice confirm improved insulin sensitivity and glucose homeostasis. In conclusion, genetic inactivation of ANGPTL4 is associated with improved glucose homeostasis and reduced risk of T2D.

Genetic risk factors influence nighttime blood pressure and related cardiovascular complications in patients with coronary heart disease.

Genetic predisposition of elevated nighttime blood pressure (BP) in patients with coronary heart disease is unknown. We evaluated genetic predisposition and the relationship between elevated nighttime BP and cardiovascular complications over a median of 8.6 years of observation of hypertensive subjects with coronary atherosclerosis confirmed by coronary angiography. Genetic Risk Score (GRS19) was constructed to evaluate the additive effect of single-nucleotide polymorphisms for daytime and nighttime BP. The Receiver Operating Characteristic was used for determination of cutoff points for daytime BP (systolic BP (SBP) 133 mm Hg and diastolic BP (DBP) 77 mm Hg) and nighttime BP (SBP 122 mm Hg and DBP 73 mm Hg). The curves of cumulative incidence revealed an increased risk of major advanced cardiovascular events in subjects with elevated nighttime BP compared with those without elevated nighttime BP during the follow-up period. Subjects with normal daytime and elevated nighttime BP exhibited increased GRS19 compared with those with normal daytime and nighttime BPs (8.6±3.0 vs. 7.9±3.0, P<0.01). After adjustment for cardiovascular risk factors, GRS19 determined nighttime SBP (ß 0.4, 95% confidence interval (CI) 0.3-0.5, P<0.01). Our study confirmed that elevated nighttime SBP was genetically determined and related to an increased risk of major adverse coronary events in patients with confirmed coronary atherosclerosis.

Elevated ambulatory systolic-diastolic pressure regression index is genetically determined in hypertensive patients with coronary heart disease.

OBJECTIVES: Ambulatory systolic-diastolic pressure regression index (ASDPRI) as a composite marker of cardiovascular (CV) properties is related to CV complications. However, genetic determinants of ASDPRI are not known. The aim of this study is to report the relationship between certain single nucleotide polymorphisms (SNP) and ASDPRI in hypertensive patients with CAD confirmed by coronary angiography. METHODS: A total of 1345 hypertensive subjects with CAD were included. SNPs were selected from genome-wide association studies. SNPs were reported to be associated with coronary artery disease risk. There were significant differences in 24 h and daytime and nighttime ASDPRIs for PHCTR1, LPA and ADAMTS7 polymorphisms. Genetic risk score (GRS18) was constructed to evaluate additive effect of 18 SNPs for ASDPRI. RESULTS: Analysis of covariance revealed a significant relationship between the PPAB2B (ß - 0.85; 95 CI -1.85--0.16, p < 0.02), WDR12 (ß - 1.31; 95 CI -2.19--0.43, p < 0.01) polymorphisms and nighttime ASDPRI dipping. Analysis of covariance revealed a significant relationship between GRS 18 and 24-h ASDPRI (ß 0.34; 95 CI 0.16-0.31, p < 0.01). CONCLUSIONS: In conclusion, ADAMTS7 and LPA polymorphisms are related to 24-h ASDPRI but PPAB2B and WDR12 gene polymorphisms are associated with nighttime ASDPRI dipping. A total of 24-h ASDPRI is determined by GRS18.

Relationship between selected DNA polymorphisms and coronary artery disease complications.

BACKGROUND: Coronary heart disease (CHD) development is complex in origin, with contributions from well-defined lifestyle and not well-determined genetic risk factors. The aim of this study is to report the relationship between certain SNPs and the risk of cardiovascular (CV) complications in patients with CAD confirmed by coronary angiography. METHODS: In the present study, 1345 subjects with CHD were included. The median follow-up period was 8.6years. 19 SNPs were investigated for any association with Major Advanced CV Events (MACE), Acute Coronary Syndromes (ACS) and Revascularizations. We modeled the 19 SNPs as a multilocus genetic risk score (GRS19). RESULTS: During follow-up period, 245 participants died; 114 due to CV causes. A fatal or non-fatal CV event occurred in 882 participants including 214 ACS, 578 revascularizations and 90 strokes. The alleles of the following SNPs: rs1746048 (CXCL12), rs9818870 (MRAS) and rs17114036 (PPAP2B) were associated with a higher risk of MACE and the alleles of SNPs rs1746048 (CXCL12) and rs1122608 (LDLR) were associated with a higher risk of revascularization. The alleles of rs12190287 (MRAS), rs121902287 (TCF21) and rs2259816 (HNF1a) were associated with a higher risk of ACS. Despite the lack of relationship between significant CAD and GRS19, in the top quartile of GRS19 there was significant relationship between GRS19 and combined endpoint, MACE, ACS, and revascularization. CONCLUSIONS: Conclusions. The SNPs of CXCL12 and LDLR were associated with risk of revascularization and CXCL12, LPA, MRAS, and PPAP2B were associated with the risk of MACE. GRS19 determines CV complications in CAD patients with the highest genetic risk score values.

The Relationship Between Gene Polymorphisms and Dipping Profile in Patients With Coronary Heart Disease.

BACKGROUND: The aim of this study is to report the relationship between certain single-nucleotide polymorphisms (SNPs) and blunted nighttime blood pressure (BP) fall in patients with coronary artery disease confirmed by coronary angiography. METHODS: According to the percentage decrease in mean systolic BP (SBP) and diastolic BP (DBP) during the nighttime period, subjects were classified as dippers or nondippers (nighttime relative SBP or DBP decline ≥10% and <10%, respectively). Genetic risk score (GRS18) was constructed to evaluate additive effect of 18 SNPs for nondipping status. RESULTS: In the present study, 1,345 subjects with coronary heart disease (CHD) were included. During follow-up period (median 8.3 years, interquartile range 5.3-9.0 years), there were 245 all-cause deaths (18.2%) including 114 cardiovascular deaths (8.5%). There were significant differences in the number of revascularizations between nondippers SBP and DBP and dippers SBP and DBP (48.0% vs. 36.4%, P < 0.01). SNPs of the genes, MIA3, MRAS, PCSK9, SMG6, and ZC3HC1, were related to a higher risk of nondipping SBP and DBP status. CONCLUSIONS: In the present study, polymorphisms of genes related to CHD (MIA3, MRAS, PCSK9, SMG6, and ZC3HC1) were associated with nondipping SBP and DBP profile, and GRS18 was associated with nondipping status. In addition, this profile was related to a higher risk of revascularization.

Discovery of Genetic Variation on Chromosome 5q22 Associated with Mortality in Heart Failure.

Failure of the human heart to maintain sufficient output of blood for the demands of the body, heart failure, is a common condition with high mortality even with modern therapeutic alternatives. To identify molecular determinants of mortality in patients with new-onset heart failure, we performed a meta-analysis of genome-wide association studies and follow-up genotyping in independent populations. We identified and replicated an association for a genetic variant on chromosome 5q22 with 36% increased risk of death in subjects with heart failure (rs9885413, P = 2.7x10-9). We provide evidence from reporter gene assays, computational predictions and epigenomic marks that this polymorphism increases activity of an enhancer region active in multiple human tissues. The polymorphism was further reproducibly associated with a DNA methylation signature in whole blood (P = 4.5x10-40) that also associated with allergic sensitization and expression in blood of the cytokine TSLP (P = 1.1x10-4). Knockdown of the transcription factor predicted to bind the enhancer region (NHLH1) in a human cell line (HEK293) expressing NHLH1 resulted in lower TSLP expression. In addition, we observed evidence of recent positive selection acting on the risk allele in populations of African descent. Our findings provide novel genetic leads to factors that influence mortality in patients with heart failure.

Genetic vasopressin 1b receptor variance in overweight and diabetes mellitus.

OBJECTIVE: Recently, imbalance in the vasopressin (AVP) system, measured as elevated levels of copeptin (the C-terminal part of the AVP pro-hormone) in plasma, was linked to the development of abdominal obesity and diabetes mellitus (DM). Here, we aim to investigate if the genetic variation of the human AVP receptor 1b gene (AVPR1B) is associated with measures of obesity and DM. DESIGN: Malmö Diet and Cancer study (MDC) is a population-based prospective cohort examined 1991-1996. METHODS: Four tag single nucleotide polymorphisms (SNPs: rs35810727, rs28373064, rs35439639, rs35608965) of AVPR1B were genotyped in the cardiovascular cohort (n=6103) of MDC (MDC-CC) and associated with measures of obesity and DM. Significant SNPs were replicated in another 24 344 MDC individuals (MDC replication cohort). RESULTS: In MDC-CC, the major allele of rs35810727 was associated with elevated BMI (ß-coefficient ± s.e.m.; 0.30 ± 0.14, P=0.03) and waist (0.78 ± 0.36, P=0.03) after age and gender adjustment. The association with BMI was replicated in the MDC replication cohort (0.21 ± 0.07, P=0.003), whereas that with waist was not significant. In MDC-CC there was no association between the major allele of rs35810727 and DM, but in the complete MDC cohort (n=30 447) the major allele of rs35810727 was associated with DM (OR (95% CI); 1.10 (1.00-1.20), P=0.04). CONCLUSIONS: Genetic variance of AVPR1B contributes to overweight. Furthermore, our data indicate a link between AVPR1B variance and DM development. Our data point at a relationship between the disturbance of the pharmacologically modifiable AVP system and the body weight regulation.

A genetic risk score for hypertension associates with the risk of ischemic stroke in a Swedish case-control study.

Genetic risk scores (GRS), summing up the total effect of several single-nucleotide polymorphisms (SNPs) in genes associated with either coronary risk or cardiovascular risk factors, have been tested for association with ischemic stroke with conflicting results. Recently an association was found between a GRS based on 29 SNPs discovered by genome-wide association studies and hypertension. The aim of our study was to investigate the possible association of the same GRS with ischemic stroke on top of other 'traditional risk factors', also testing its potential improvement in indices of discrimination and reclassification, in a Swedish case-control study. Twenty-nine SNPs were genotyped in 3677 stroke cases and 2415 controls included in the Lund Stroke Register (LSR), the Malmö Diet and Cancer (MDC) study and the Sahlgrenska Academy Study on Ischemic Stroke (SAHLSIS). The analysis was conducted in the combined sample, and separately for the three studies. After adjustment for hypertension, diabetes mellitus and smoking habits, the GRS was associated with ischemic stroke in the combined sample (OR (95% CI) 1.086 (1.029-1.147) per SD increase in the GRS P=0.003) with similar trends in all three samples: LSR (1.050 (0.967-1.140); P=0.25), MDC (1.168 (1.060-1.288); P=0.002) and SAHLSIS (1.124 (0.997-1.267); P=0.055). Measures of risk discrimination and reclassification improved marginally using the GRS. A blood pressure GRS is independently associated with ischemic stroke risk in three Swedish case-control studies, however, the effect size is low and adds marginally to prediction of stroke on top of traditional risk factors including hypertension.

Twelve-single nucleotide polymorphism genetic risk score identifies individuals at increased risk for future atrial fibrillation and stroke.

BACKGROUND AND PURPOSE: Atrial fibrillation (AF) is prevalent and there is a clinical need for biomarkers to identify individuals at higher risk for AF. Fixed throughout a life course and assayable early in life, genetic biomarkers may meet this need. Here, we investigate whether multiple single nucleotide polymorphisms together as an AF genetic risk score (AF-GRS) can improve prediction of one's risk for AF. METHODS: In 27 471 participants of the Malmö Diet and Cancer Study, a prospective, community-based cohort, we used Cox models that adjusted for established AF risk factors to assess the association of AF-GRS with incident AF and ischemic stroke. Median follow-up was 14.4 years for incident AF and 14.5 years for ischemic stroke. The AF-GRS comprised 12 single nucleotide polymorphisms that had been previously shown to be associated with AF at genome-wide significance. RESULTS: During follow-up, 2160 participants experienced a first AF event and 1495 had a first ischemic stroke event. Participants in the top AF-GRS quintile were at increased risk for incident AF (hazard ratio, 2.00; 95% confidence interval, 1.73-2.31; P=2.7×10(-21)) and ischemic stroke (hazard ratio, 1.23; 95% confidence interval, 1.04-1.46; P=0.02) when compared with the bottom quintile. Addition of the AF-GRS to established AF risk factors modestly improved both discrimination and reclassification (P<0.0001 for both). CONCLUSIONS: An AF-GRS can identify 20% of individuals who are at ≈2-fold increased risk for incident AF and at 23% increased risk for ischemic stroke. Targeting diagnostic or therapeutic interventions to this subset may prove clinically useful.

Cardiovascular consequences of a polygenetic component of blood pressure in an urban-based longitudinal study: the Malmö diet and cancer.

BACKGROUND: A recently published genome wide association study identified 29 single nucleotide polymorphisms (SNPs) influencing blood pressure (BP). Case-control studies suggest that a genetic risk score (GRS) based on these 29 SNPs affect the risk of cardiovascular disease (CVD), but its role for CVD at population level is unknown. Here, we prospectively evaluate the impact of this polygenetic BP component on CVD morbidity and mortality in a large urban-based middle-aged population. METHOD: The 29 previously BP associated SNPs were genotyped in the Swedish Malmö Diet and Cancer Study; (n = 27,003 with at least 24 valid SNPs). The number of BP elevating alleles of each SNPs, weighted by their effect size in the discovery studies, was summed into a BP-GRS. RESULTS: Using regression models, we found significant associations of the BP-GRS, cross-sectionally, with BP and hypertension prevalence, prospectively, with incident cardiovascular morbidity and mortality during 14.2 ± 3.2 years of follow-up. After adjustment for traditional cardiovascular risk factors (TRF), including hypertension, the BP-GRS remained significantly associated only with CVDs [in terms of strokes and coronary artery disease; hazard ratio 1.15; 95% confidence interval (CI) 1.06-1.24 comparing the third vs. first tertile; P = 0.003]. Calibration, discrimination and reclassification analyses did not show a meaningful increment in prediction using the BP-GRS in addition to the model encompassing only the TRF. CONCLUSION: The polygenetic component of BP influences risk of cardiovascular morbidity and mortality. However, the effect size is small and unlikely to be useful for prediction at the population level.

Association of BTG2, CYR61, ZFP36, and SCD gene polymorphisms with Graves' disease and ophthalmopathy.

BACKGROUND: Environmental and genetic factors predispose an individual to the development of Graves' disease (GD). In an expression study of intraorbital tissue, adipocyte-related immediate early genes (IEGs) and immunomodulatory genes were found to be overexpressed in patients with Graves' ophthalmopathy (GO). We hypothesized that genetic variations in these genes could be associated with GD and/or GO. METHODS: A total of 98 single nucleotide polymorphisms (SNPs) in 12 genes were genotyped in 594 GD patients with (n=267) or without (n=327) GO and 1147 sex- and ethnicity-matched controls from Malmö, Sweden. RESULTS: Ten SNPs in four genes (BTG family, member 2 [BTG2], cysteine-rich, angiogenic inducer 61 [CYR61], zinc finger protein 36, C3H type, homolog mouse [ZFP36], and stearoyl-coenzyme A desaturase [SCD]) showed an association with GD and/or GO. SNPs rs12136280 (odds ratio [OR] 1.29, p=0.002), rs6663606 (OR 1.26, p=0.004), and rs17534202 (OR 1.21, p=0.02) in BTG2 and rs3753793 (OR 1.21, p=0.03) in CYR61 were associated with GD. An association with GO was shown for SNPs rs3753793 (OR 1.45, p=0.008), rs6682848 (OR 1.55, p=0.03), rs12756618 (OR 1.77, p=0.049), and rs1378228 (OR 1.29, p=0.049) in CYR61, rs1057745 (OR 1.56, p=0.03) and rs11083522 (OR 1.32, p=0.04) in ZFP36, and rs1393491 (OR 1.38, p=0,048) in SCD. Smoking and CYR61 rs12756618 interacted to increase the risk of GO. CONCLUSIONS: We found associations of SNPs in IEGs and SCD with GD and/or GO; however, confirmation in a different population is required.

Smoking modifies the associated increased risk of future cardiovascular disease by genetic variation on chromosome 9p21.

AIMS: Genetic predisposition for cardiovascular disease (CVD) is likely to be modified by environmental exposures. We tested if the associated risk of CVD and CVD-mortality by the single nucleotide polymorphism rs4977574 on chromosome 9p21 is modified by life-style factors. METHODS AND RESULTS: A total of 24,944 middle-aged subjects (62% females) from the population-based Malmö-Diet-and-Cancer-Cohort were genotyped. Smoking, education and physical activity-levels were recorded. Subjects were followed for 15 years for incidence of coronary artery disease (CAD; N = 2309), ischemic stroke (N = 1253) and CVD-mortality (N = 1156). Multiplicative interactions between rs4977574 and life-style factors on endpoints were tested in Cox-regression-models. We observed an interaction between rs4977574 and smoking on incident CAD (P = 0.035) and CVD-mortality (P = 0.012). The hazard ratios (HR) per risk allele of rs4977574 were highest in never smokers (N = 9642) for CAD (HR = 1.26; 95% CI 1.13-1.40; P<0.001) and for CVD-mortality (HR = 1.40; 95% CI 1.20-1.63; P<0.001), whereas the risk increase by rs4977574 was attenuated in current smokers (N = 7000) for both CAD (HR = 1.05; 95%CI 0.95-1.16; P = 0.326) and CVD-mortality (HR = 1.08; 95%CI 0.94-1.23; P = 0.270). A meta-analysis supported the finding that the associated increased risk of CAD by the risk-allele was attenuated in smokers. Neither education nor physical activity-levels modified the associated risk of CAD, ischemic stroke and CVD mortality conferred by rs4977574. CONCLUSION: Smoking may modify the associated risk of CAD and CVD-mortality conferred by genetic variation on chromosome 9p21. Whether the observed attenuation of the genetic risk reflects a pathophysiological mechanism or is a result of smoking being such a strong risk-factor that it may eliminate the associated genetic effect, requires further investigation.

Genetic variation in NEDD4L, an epithelial sodium channel regulator, is associated with cardiovascular disease and cardiovascular death.

OBJECTIVES: We have previously shown that genetic variance in NEDD4L, a regulating protein of a sodium channel in the distal nephron, has been associated with marginally higher blood pressure and enhanced salt sensitivity. Here, we tested if the genetic NEDD4L variation previously associated with salt sensitivity is related to population blood pressure, incidence of cardiovascular disease (CVD) and mortality. METHOD: We genotyped the rs4149601 A→G and rs2288774 T→C NEDD4L variants in 27,564 participants of the Malmö Diet and Cancer Study. The genotype combination previously shown to be associated with salt sensitivity (rs4149601 GG+rs2288774 CC), which was present in 9.6% of participants, was related to cross sectional blood pressure as well as to CVD incidence and mortality during a median follow-up time of 14 years using Cox regression models. RESULTS: Carriers of the NEDD4L salt sensitivity-associated genotype had (mean ± SEM) higher systolic (142 ± 0.4 vs. 141 ± 0.1 mmHg, P = 0.002) and diastolic (86.0 ± 0.5 vs. 85.6 ± 0.2 mmHg, P = 0.025) blood pressure and multivariate adjusted hazards ratio (95% confidence interval) of CVD 1.13 (1.02-1.25, P = 0.018), coronary events 1.20 (1.06-1.37; P = 0.005) and cardiovascular mortality 1.17 (0.99-1.37; P = 0.055) than noncarriers but there was no significant difference in the incidence of stroke and total mortality. CONCLUSION: The NEDD4L salt sensitivity-associated genotype was associated with higher blood pressure, which may translate into increased risk for CVD morbidity and mortality. Interestingly, there was no association with stroke suggesting that the association is partially blood pressure independent.

Smoking and obesity associated BDNF gene variance predicts total and cardiovascular mortality in smokers.

OBJECTIVE: The brain derived neurotrophic factor (BDNF) locus has been implicated in psychiatric and substance related disorders. Recent genome-wide association studies (GWAS) have shown strong associations between single nucleotide polymorphisms in BDNF, smoking behaviour and high body mass index (BMI). Our aim was to test whether genetic BDNF variation alters the risk of smoking related morbidity and mortality. DESIGN: Cox proportional hazards models were used to relate the BDNF rs4923461(A/G) polymorphisms to all-cause, cancer and cardiovascular mortality and cardiovascular disease (CVD) incidence adjusted for age, sex, BMI, and smoking quantity. SETTING: The Malmö Diet and Cancer Study (MDCS), a population based prospective cohort study (n=30 447). PATIENTS: We obtained complete data on 25 071 subjects, of whom 6507 were current smokers and 18 564 were non-smokers who underwent a baseline examination from 1991-1996. MAIN OUTCOME MEASURES: During a mean follow-up time of 12 years, 1049 deaths (346 cardiovascular deaths and 492 cancer deaths) and 802 incident CVD events occurred among current smokers. RESULTS: The major allele (A) of rs4923461 was significantly associated with ever having smoked (p=0.03) and high BMI (p=0.001). The A-allele was associated with risk of all-cause (HR=1.12, 95% CI 1.00 to 1.25; p<0.05) and CVD (HR=1.23, 95% CI 1.01 to 1.49; p=0.04) mortality. There was no significant association between the rs4923461 and cancer mortality or CVD incidence. CONCLUSIONS: Our data suggest that smoking- and obesity-associated variation of the BDNF gene affects the risk of death, especially due to cardiovascular causes, in smokers. Determination of the BDNF genotype in smokers may guide the need for smoking cessation interventions.

Genetic associations with valvular calcification and aortic stenosis.

BACKGROUND: Limited information is available regarding genetic contributions to valvular calcification, which is an important precursor of clinical valve disease. METHODS: We determined genomewide associations with the presence of aortic-valve calcification (among 6942 participants) and mitral annular calcification (among 3795 participants), as detected by computed tomographic (CT) scanning; the study population for this analysis included persons of white European ancestry from three cohorts participating in the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium (discovery population). Findings were replicated in independent cohorts of persons with either CT-detected valvular calcification or clinical aortic stenosis. RESULTS: One SNP in the lipoprotein(a) (LPA) locus (rs10455872) reached genomewide significance for the presence of aortic-valve calcification (odds ratio per allele, 2.05; P=9.0×10(-10)), a finding that was replicated in additional white European, African-American, and Hispanic-American cohorts (P<0.05 for all comparisons). Genetically determined Lp(a) levels, as predicted by LPA genotype, were also associated with aortic-valve calcification, supporting a causal role for Lp(a). In prospective analyses, LPA genotype was associated with incident aortic stenosis (hazard ratio per allele, 1.68; 95% confidence interval [CI], 1.32 to 2.15) and aortic-valve replacement (hazard ratio, 1.54; 95% CI, 1.05 to 2.27) in a large Swedish cohort; the association with incident aortic stenosis was also replicated in an independent Danish cohort. Two SNPs (rs17659543 and rs13415097) near the proinflammatory gene IL1F9 achieved genomewide significance for mitral annular calcification (P=1.5×10(-8) and P=1.8×10(-8), respectively), but the findings were not replicated consistently. CONCLUSIONS: Genetic variation in the LPA locus, mediated by Lp(a) levels, is associated with aortic-valve calcification across multiple ethnic groups and with incident clinical aortic stenosis. (Funded by the National Heart, Lung, and Blood Institute and others.).

Genetic polymorphisms confer risk of atrial fibrillation in patients with heart failure: a population-based study.

AIMS: Atrial fibrillation (AF) is a frequent co-morbidity in heart failure (HF) associated with increased mortality, but little is known about the mechanisms underlying AF onset in HF patients. We evaluated the association of cardiovascular and genetic risk factors with AF in HF patients. METHODS AND RESULTS: Individuals hospitalized for HF (n = 1040; 500 with AF) were identified from a large, population-based cohort study (n = 30 447; 2339 with AF). Genetic polymorphisms in the chromosomal regions 4q25 (rs2200733) and 16q22 (rs2106261) associated with AF in genome-wide association studies were genotyped. Association of cardiovascular risk factors and polymorphisms with AF was tested in HF patients and the entire cohort using both prospective and non-time-dependent models. Cardiovascular risk factors-hypertension, body mass index, sex, smoking, diabetes, and myocardial infarction-were associated with AF in the entire cohort but not in HF patients. In contrast, polymorphisms on chromosomes 16q22 and 4q25 were associated with AF both in the entire cohort and in HF patients, conferring 75% [95% confidence interval (CI) 35-126, P = 2 × 10(-5)] and 57% (95% CI 18-109, P = 0.002) increased risk of AF per copy in HF patients, respectively. In the entire cohort, AF risk in the presence of HF was multiplicatively magnified by genotype for 16q22 (P for interaction = 7 × 10(-4)) but not 4q25 (P = 0.83). In prospective analyses excluding patients with AF diagnosis prior to or simultaneously with HF diagnosis, 16q22 but not 4q25 remained robustly associated with AF (hazard ratio 1.96, 95% CI 1.40-2.73, P = 8 × 10(-5)). The proportion of AF diagnoses in HF patients attributable to polymorphisms was 19% and 12%, respectively. CONCLUSIONS: A polymorphism in the ZFHX3 gene, encoding a cardiac transcription factor, was associated with increased AF risk in HF patients, and the genetic association with AF was more pronounced in HF patients than in the general population.