Search

Objective: The gut microbiota is increasingly being implicated in cardiovascular health. Metabolites produced by bacteria have been suggested to be mediators in the bacterial action on cardiovascular health. We aimed to identify gut microbiota-related plasma metabolites and test whether these metabolites associate with future risk of coronary artery disease (CAD)., Methods: Nontargeted metabolomics was performed using liquid chromatography-mass spectrometry in order to measure 1446 metabolite features in the Malmö Offspring Study (MOS) (N = 776). The gut microbiota was characterized using 16S rRNA sequencing. Gut bacteria-related metabolites were measured in two independent prospective cohorts, the Malmö Diet and Cancer - Cardiovascular Cohort (MDC-CC) (N = 3361) and the Malmö Preventive Project (MPP) (N = 880), in order to investigate the associations between gut bacteria-related metabolites and risk of CAD., Results: In MOS, 33 metabolite features were significantly (P < 4.8e-7) correlated with at least one operational taxonomic unit. Phenylacetylglutamine (PAG) was associated with an increased risk of future CAD, using inverse variance weighted meta-analysis of age and sex-adjusted logistic regression models in MDC-CC and MPP. PAG remained significantly associated with CAD (OR = 1.17, 95% CI = 1.06-1.29, P = 1.9e-3) after adjustments for cardiovascular risk factors., Conclusion: The levels of 33 plasma metabolites were correlated with the gut microbiota. Out of these, PAG was associated with an increased risk of future CAD independently of other cardiovascular risk factors. Our results highlight a link between the gut microbiota and CAD risk and should encourage further studies testing if modification of PAG levels inhibits development of CAD.

Objectives: Elevated plasma levels of the vasodilating hormone adrenomedullin (ADM) predict cardiovascular disease and have been associated with hypertension and obesity. We aimed to examine the independent relationship between ADM and the progression of major cardiometabolic risk factors during long-term follow-up., Methods: We studied midregional pro-ADM (MR-proADM) in fasting plasma in 3298 participants from the population-based Malmö Diet and Cancer Study - Cardiovascular Cohort, re-examined after 17 years of follow-up and related baseline MR-proADM to cardiometabolic risk factors cross-sectionally and longitudinally., Results: At baseline, after full adjustment, each SD increment of MR-proADM was independently related to (beta ± standard error, P value) higher SBP (0.956 ± 0.319 mmHg, P = 0.003), BMI (0.912 ± 0.061 kg/m, P = 1.42 × 10), waist (2.28 ± 0.158 cm, P = 8.46 × 10) and fasting blood glucose (0.046 ± 0.018 mmol/l, P = 0.01). After full adjustment, including the baseline level of the risk factor whose degree of progression was studied, each SD increment of MR-proADM predicted significantly reduced progression of SBP (-1.170 ± 0.337 mmHg, P = 0.001) and fasting blood glucose (-0.055 ± 0.023 mmol/l, P = 0.015), but greater increase of BMI (0.101 ± 0.051 kg/m, P = 0.047) and waist (0.600 ± 0.144 cm, P = 3.1 × 10)., Conclusion: Despite cross-sectional associations with higher levels of blood pressure and glucose, high levels of MR-proADM predict a slower progression of blood pressure and glycemia during long-term follow-up. Conversely, the cross-sectional associations with higher levels of MR-proADM and obesity were paralleled by a faster progression of obesity markers over time. These results may be important for assessment of long-term effects of therapies modulating levels of ADM.

Introduction: Arterial stiffness is recognized as an intermediate phenotype and predictor of cardiovascular disease. Arterial stiffness is complex in origin with contributions from lifestyle and genetic factors. However, the association between single nucleotide polymorphisms (SNPs) and arterial stiffness remains unclear., Objective: The aim is to assess whether a multilocus genetic risk score (GRS), composed of selected SNPs linked to cardiovascular traits and outcomes, is associated with arterial stiffness in patients with hypertension., Design and Methods: This study included 730 participants derived from the CARE NORTH study. The arterial stiffness was evaluated by carotid-femoral pulse wave velocity (cfPWV). An adjusted linear regression was used to evaluate the association between cfPWV and each individual SNP using multiple genetic models. The association between a constructed GRS and cfPWV was tested in an unadjusted and adjusted model., Results: We selected 13 SNPs found to be associated with cfPWV (P < .05): 6 SNPs in additive, 4 SNPs in recessive and 3 SNPs in dominant mode of inheritance. The GRS based on these SNPs was positively associated with cfPWV both in unadjusted and adjusted models (β = 0.2 m/s, 95% CI 0.11 - 0.29, P = 7.6 × 10 and β = 0.22 m/s, 95% CI 0.15 - 0.28, P = 1.4 × 10, respectively). The GRS explained an additional 3.6% cfPWV variance above clinical covariates., Conclusion: We demonstrate that the GRS composed of 13 SNPs related to cardiovascular phenotypes is associated with an increased arterial stiffness in hypertensive patients. Our findings may help to clarify genetic basis of arterial stiffening and provide insight into mechanisms underlying this phenotype.

Background: Arterial stiffness is known to be associated with a number of clinical conditions including hypertension, diabetes and dyslipidemia, and may predict cardiovascular events and mortality. However, causal links are hard to establish. Results from genome-wide association studies have identified only a few single nucleotide polymorphisms associated with arterial stiffness, the results have been inconsistent between studies and overlap with other clinical conditions is lacking. Our aim was to investigate a potential shared set of risk single nucleotide polymorphisms between relevant cardiometabolic traits and arterial stiffness., Method: The study population consisted of 2853 individuals (mean age 72 years, 40% men) from the population-based Malmö Diet and Cancer study, Sweden. Carotid-femoral pulse wave velocity, a marker of arterial stiffness, was measured with Sphygmocor. Mendelian randomization analyses were performed using the two-stage least square regression and multivariate inverse-variance weighted methods., Results: There were positive associations between arterial stiffness and genetic risk scores for type 2 diabetes (β = 0.03, P = 0.04) and fasting plasma glucose (β = 0.03, P = 0.03), but not for systolic blood pressure, body mass index, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol or triglycerides. Multivariate inverse-variance weighted methods confirmed the significant positive association for fasting plasma glucose β coefficients (P = 0.006), but not for type 2 diabetes β coefficients (P = 0.88)., Conclusion: Genetically elevated fasting plasma glucose, but not genetically elevated risk of type 2 diabetes, was associated with arterial stiffness suggesting a causal stiffening effect of glycemia on the arterial wall, independently of type 2 diabetes.

Objective(s): We explored incidence, predictors, and long-term prognosis of hospital admissions attributed to reflex syncope and orthostatic hypotension., Methods: We analyzed a cohort of 32 628 individuals (68.2% men; age, 45.6 ± 7.4 years) without prevalent cardiovascular disease over a follow-up period of 26.6 ± 7.5 years., Results: One thousand and fourteen persons (3.1%, 1.2 per 1000 person-years) had at least 1 hospitalization for orthostatic hypotension (n = 462, 1.42%) or syncope (n = 632, 1.94%). Orthostatic hypotension-related hospitalizations were predicted by age [per 1-year increase, hazard ratio 1.14, 95% confidence interval (CI): 1.12-1.16], smoking (hazard ratio 1.35, 95% CI: 1.12-1.64), diabetes (hazard ratio 1.50, 95% CI: 1.00-2.25), baseline orthostatic hypotension (hazard ratio 1.45, 95% CI: 1.05-1.98), in particular, by SBP fall at least 30 mmHg (hazard ratio 3.93, 95% CI: 2.14-7.23), whereas syncope hospitalizations by age (per 1-year increase, hazard ratio 1.09, 95% CI: 1.07-1.11), smoking (hazard ratio 1.27, 95% CI: 1.08-1.49), and hypertension (hazard ratio 1.42, 95% CI: 1.20-1.69). Both syncope-hospitalized and orthostatic hypotension hospitalized patients had higher burden of hospital admissions for other reasons such as cardiovascular, pulmonary, renal disease, or diabetes. During the follow-up, 10 727 (32.9%) died, with 419 deaths preceded by syncope/orthostatic hypotension hospitalization. After adjustment for traditional risk factors, syncope-hospitalization predicted all-cause mortality (hazard ratio 1.16, 95% CI: 1.02-1.31), whereas orthostatic hypotension hospitalization predicted cardiovascular mortality (hazard ratio 1.13, 95% CI: 1.07-1.19)., Conclusion: Hospital admissions due to syncope and orthostatic hypotension occur in ≈3% of older individuals and increase with age and comorbidities. Admissions due to syncope are associated with prevalent hypertension, whereas those due to orthostatic hypotension overlap with diabetes and previously identified orthostatic hypotension. Syncope-related admissions predict higher all-cause mortality, whereas orthostatic hypotension-related admissions herald increased cardiovascular mortality.

Objective: To identify stop-codon variants associated with blood pressure (BP)., Methods: Illumina exome chip was genotyped in 5453 individuals of the population-based Malmö Diet and Cancer Study. We compared BP levels between carriers and noncarriers of all stop-codon variants found in at least 10 individuals and characterized these further based on literature evidence of functionality. Next, the association to ischemic stroke was evaluated in 2278 cases of ischemic stroke and 5969 controls., Results: We identified 19 stop-codon variants with nominally significant BP associations (P < 0.05). One of these, located in the phosphodiesterase 11A (PDE11A) gene (R307X), has previously been reported to cause loss of PDE11A function and Cushing's syndrome in female carriers. In the Malmö Diet and Cancer Study, 1% of the population carried R307X and had age and sex-adjusted (mean, 95% confidence interval) 5.0, 0.29-9.7 (P = 0.038), and 3.3, 0.83-5.7 (P = 0.009) mmHg higher SBP and DBP than noncarriers and also significantly higher waist circumference and BMI. Among females, carriers of the R307X had age adjusted 8.3, 2.3-14 (P = 0.006) and 4.7, 1.7-7.7 (P = 0.002) mmHg higher SBP and DBP, 4.3, 0.84-7.8 (P = 0.015)  cm higher waist circumference and 1.7, 0.30-3.1 (P = 0.018)  kg/m higher BMI. In addition, carriers of the R307X mutation had an odds ratio of ischemic stroke of 1.73 (95% confidence interval 1.06-2.82); P = 0.028., Conclusion: One percent of the Swedish population carries a PDE11A loss-of-function mutation associated with elevated BP, abdominal obesity, and risk of ischemic stroke.

Objectives: Orthostatic hypotension has been linked with increased mortality and cardiovascular morbidity; however, the underlying mechanisms are still unknown. The aim of the study was to assess markers of coagulability in patients with and without orthostatic hypotension who suffered transient loss of consciousness., Methods: A total of 233 consecutive patients more than 15 years old, with unexplained transient loss of consciousness, underwent head-up tilt test (HUT, Italian protocol). Blood samples were collected during supine rest before and at 3 min of 70° HUT for determination of fibrinogen, von Willebrand factor antigen (vWF:Ag) and activity (vWF:GP1bA), factor VIII (FVIII:C), lupus anticoagulant, and functional activated protein C-resistance. Orthostatic hypotension was defined as persistent decrease in SBP and/or DBP of more than 20/10 mmHg or SBP lower than 90 mmHg during passive HUT., Results: One hundred and seventy-eight patients (81 men, 45.5%) not treated with vitamin-K antagonists were analyzed. Those with orthostatic hypotension (n = 49) were older [61 ± 18 vs. 47 ± 21 years (mean ± SD), P < 0.001], had increased, Fviii: C-supine (1.2 ± 0.39 vs. 1.0 ± 0.35, P = 0.001), FVIII:C-standing (1.2 ± 0.36 vs. 1.0 ± 0.34, P = 0.001), vWF:Ag-supine (1.5 ± 0.66 vs. 1.1 ± 0.44, P < 0.001), vWF:Ag-standing (1.5 ± 0.67 vs. 1.1 ± 0.46, P < 0.001), vWF:GP1bA-supine (1.5 ± 0.73 vs. 1.1 ± 0.42, P < 0.001), vWF:GP1bA-standing (1.5 ± 0.75 vs. 1.1 ± 0.42 P < 0.001), fibrinogen-standing (2.9 ± 0.53 vs. 2.7 ± 0.61, P = 0.03) but not fibrinogen-supine (2.8 ± 0.54 vs. 2.7 ± 0.61, P = 0.078) compared with patients without orthostatic hypotension. However, after adjustment for age, sex, and comorbidity, only vWF:Ag and vWF:GP1bA levels remained significantly increased in orthostatic hypotension patients., Conclusion: Concentration of vWF is elevated in patients with orthostatic hypotension who suffered a syncopal event. This observation may be helpful in understanding the increased risk of cardiovascular events in orthostatic hypotension.

Background: Thiazide diuretics have been recommended as a first-line antihypertensive treatment, although the choice of 'the right drug in the individual essential hypertensive patient' remains still empirical. Essential hypertension is a complex, polygenic disease derived from the interaction of patient's genetic background with the environment. Pharmacogenomics could be a useful tool to pinpoint gene variants involved in antihypertensive drug response, thus optimizing therapeutic advantages and minimizing side effects., Methods and Results: We looked for variants associated with blood pressure response to hydrochlorothiazide over an 8-week follow-up by means of a genome-wide association analysis in two Italian cohorts of never-treated essential hypertensive patients: 343 samples from Sardinia and 142 from Milan. TET2 and CSMD1 as plausible candidate genes to affect SBP response to hydrochlorothiazide were identified. The specificity of our findings for hydrochlorothiazide was confirmed in an independent cohort of essential hypertensive patients treated with losartan. Our best findings were also tested for replication in four independent hypertensive samples of European Ancestry, such as GENetics of drug RESponsiveness in essential hypertension, Genetic Epidemiology of Responses to Antihypertensives, NORdic DILtiazem intervention, Pharmacogenomics Evaluation of Antihypertensive Responses, and Campania Salute Network-StayOnDiur. We validated a polymorphism in CSMD1 and UGGT2., Conclusion: This exploratory study reports two plausible loci associated with SBP response to hydrochlorothiazide: TET2, an aldosterone-responsive mediator of αENaC gene transcription; and CSMD1, previously described as associated with hypertension in a case-control study.

Background: Arterial stiffness plays a fundamental role in the development of hypertension and is a risk factor for both cardiovascular disease and mortality. The stiffening that occurs with increasing age has, in numerous cross-sectional studies, been shown to be associated with several cardiovascular risk factors. This observational study aims to characterize the predictive and cross-sectional markers focusing on the non-hemodynamic component of arterial stiffness., Method: In all, 2679 men and women from Malmö, Sweden, were examined at baseline during 1991-1994, and again at follow-up during 2007-2012 (mean age 72 years, 38% men). Follow-up examination included measurement of arterial stiffness by carotid-femoral pulse wave velocity (c-fPWV), after a mean period of 17 years. The associations between c-fPWV and risk markers were calculated with multiple linear regression., Results: The results indicated that for both sexes, waist circumference (β = 0.17, P < 0.001), fasting glucose (β = 0.13, P < 0.001), Homeostatic Model Assessment - Insulin Resistance (β = 0.10, P < 0.001), triglycerides (β = 0.10, P < 0.001), and high-density lipoprotein cholesterol (β = -0.08, P < 0.001) were all predictors of cfPWV adjusted for mean arterial pressure and heart rate, as well as for classical cardiovascular risk factors and drug treatment. There were no associations between baseline or follow-up low-density lipoprotein cholesterol, smoking, or eGFR and c-fPWV., Conclusion: The non-hemodynamic cluster of risk markers and predictors of arterial stiffness in a middle-aged population includes abdominal obesity, hyperglycemia, and dyslipidemia, but not smoking and low-density lipoprotein cholesterol. This pattern existed in both sexes.

Objective: Salt-induced elevation of the endogenous digitalis like sodium pump ligand marinobufagenin (MBG) in the Dahl salt-sensitive rats resulted in elevated blood pressure (BP). Here, we tested, in humans, whether MBG levels are related to ambulatory 24-h BP (ABP), controlled long-term increase of salt-intake induces changes in MBG and any salt-induced change in MBG is related to salt sensitivity., Methods: Thirty-nine healthy individuals (53 ± 11 years old; 20 men and 19 women) had a total daily NaCl intake of 50 mmol (low-salt) and 150 mmol (high-salt) for 4 weeks each, in a random order. ABP and MBG in plasma and urine were measured at baseline (unstandardized salt intake) and after high and low-salt intake., Results: At baseline, plasma MBG (P-MBG) was related to 24-h SBP (r = 0.43, P = 0.007) and DBP (r = 0.32, P = 0.047), whereas 24-h urinary excretion of MBG (UE-MBG) was related to 24-h DBP only (r = 0.42, P = 0.008). Sex-specific analyses revealed that these relationships were significant in men only. Compared with low-salt, high-salt diet increased P-MBG (P = 0.029), mainly driven by results in men. Male P-MBG responders vs. nonresponders (above vs. below median of high-salt induced P-MBG increase) had markedly enhanced SBP (10.4 ± 6.4 vs. 1.0 ± 6.0 mmHg; P = 0.003) and DBP (6.7 ± 5.0 vs. -0.6 ± 3.6 mmHg; P = 0.001) salt sensitivity., Conclusion: In men, MBG increases with 24-h ABP, and similar to Dahl salt-sensitive rats, 4 weeks of high-salt induced MBG response is accompanied by marked salt sensitivity. However, these patterns seem to be sex-specific and are not observed in women.

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.

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.

Objective: Impact of SBP vs. DBP decrement during orthostasis on cardiovascular events in hypertension is not clear., Methods: We assessed prospective association of orthostatic hypotension with mortality and major cardiovascular events [myocardial infarction (MI) and stroke] among 8788 treated hypertensive patients (52.2% men; mean age 52 years, mean BP 161/99  mmHg) without history of MI or stroke at baseline. Orthostatic hypotension was defined according to combined international consensus criteria, and as either systolic (decrease ≥20  mmHg) or diastolic orthostatic hypotension (decrease ≥10  mmHg). Final Cox regression model was adjusted for age, sex, supine SBP and DBP, diabetes, smoking, and total cholesterol., Results: A total of 1060 (12.1%) study participants fulfilled combined orthostatic hypotension criteria, of these 886 (10.1%) met systolic and 290 (3.3%) diastolic criterion. In the crude analysis, combined orthostatic hypotension criteria were predictive of the composite endpoint, major cardiovascular event, total mortality, and stroke but not MI. After full adjustment, combined orthostatic hypotension criteria and systolic orthostatic hypotension were independently associated with stroke only (hazard ratio: 1.48, 1.07-2.05, P = 0.019, and 1.53, 1.08-2.15, P = 0.015, respectively), whereas the composite endpoint tended in the same direction (hazard ratio: 1.21, 0.98-1.51, P = 0.075, and 1.24, 0.99-1.55, P = 0.066, respectively). In contrast, diastolic orthostatic hypotension was associated with increased risk of MI (hazard ratio: 2.04, 1.20-3.46, P = 0.008)., Conclusion: Orthostatic hypotension has a dual role in cardiovascular events among hypertensive patients: SBP fall indicates higher risk of stroke, whereas DBP fall confers higher risk of MI.

Background: Adrenomodulin (ADM) is a peptide hormone secreted in response to cellular strain such as ischemia and is believed to have a beneficial effect on the cardiovascular system. However, the epidemiological relationships between ADM and measurements of haemodynamics, arteriosclerosis and atherosclerosis are not well established. The aim of this study was to investigate the association between the mid-regional part of pro-ADM (MR-proADM) and brachial pulse pressure (PP), carotid intima-media thickness (cIMT) and carotid atherosclerosis., Method: This study has a cross-sectional design and includes 4924 individuals (mean age 58 years, 40% men) from Malmö, Sweden, examined between 1991 and 1994. Participants underwent physical examination, measurement of MR-proADM and ultrasound of the carotid arteries., Results: There was a positive association between MR-proADM and brachial PP, cIMT as well as a carotid plaque score. The associations were significant after adjustment for age, sex, BMI, hypertension, diabetes, low-density lipoprotein cholesterol and smoking., Conclusion: ADM is positively associated with brachial PP and both carotid IMT and plaques, suggesting a role for ADM in early haemodynamic pathophysiology related to arteriosclerosis and the atherosclerotic plaque development.

Objective: We aimed to test whether eight common recently identified single-nucleotide polymorphisms (SNPs), strongly associated with blood pressure (BP) in the population, also have impact on the degree of BP reduction by antihypertensive agents with different mechanisms., Methods: In 3863 Swedish hypertensive patients, we related number of unfavorable alleles of each SNP (i.e. alleles associated with higher baseline BP) to the magnitude of BP reduction during 6 months of monotherapy with either a beta-blocker, a thiazide diuretic or diltiazem., Results: For six SNPs (rs16998073, rs1378942, rs3184504, rs1530440, rs16948048, rs17367504) no pharmacogenetic interactions were suggested, whereas two SNPs showed nominal evidence of association with treatment response: PLCD3-rs12946454 associated with more SBP (beta = 1.53 mmHg per unfavorable allele; P = 0.010) and DBP (beta = 0.73 mmHg per unfavorable allele; P = 0.014) reduction in patients treated with diltiazem, in contrast to those treated with beta-blockers or diuretics wherein no treatment response association was found. CYP17A1-rs11191548 associated with less DBP reduction (beta = -1.26 mmHg per unfavorable allele; P = 0.018) in patients treated with beta-blockers or diuretics, whereas there was no treatment response association in diltiazem-treated patients. However, if accounting for multiple testing, the significant associations for rs12946454 and rs11191548 were attenuated., Conclusion: For a majority of these, eight recently identified BP-associated SNPs, there are probably no important pharmacogenetic interactions for BP reduction with use of beta-blockers, diuretics or diltiazem. Whether the nominally significant associations for rs12946454 and rs11191548 are true signals and could be of possible clinical relevance for deciding treatment of polygenic essential hypertension should be further tested.

Objective: The risk factor pattern underlying a parental history of myocardial infarction (MI) is incompletely understood. We examined whether a parental history of clinically verified early MI may promote development of insulin resistance, obesity and the metabolic syndrome (MetS)., Methods: One hundred and seventy-four offspring to patients with clinically verified MI before 60 years of age in the population-based prospective Malmo Diet and Cancer (MDC) study were recruited (positive parental history). As controls, we included 174 offspring of MDC participants without MI during 14 years of follow-up in the MDC (negative parental history). MetS was defined according to the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) guidelines, obesity as BMI greater than 30  kg/m and insulin resistance as the top quartile of homeostasis model assessment index in the 348 included offspring (mean age 44 years, 49% women)., Results: The odds ratio, 95% confidence interval, for MetS in positive parental history as compared with negative parental history was 2.05, 1.06-4.00 (P = 0.034) after adjustment for age, sex, low-density lipoprotein cholesterol (LDL) and smoking. positive parental history was also independently associated with obesity 2.50, 1.34-4.66 (P = 0.003), abdominal obesity 2.01, 1.21-3.33 (P = 0.007) and insulin resistance 1.97, 1.14-3.40 (P = 0.014), whereas there was no association with LDL and smoking. All of these relationships were stronger in men than in women., Conclusion: Parental history of clinically verified early MI is associated with MetS, obesity and insulin resistance rather than with traditional cardiovascular disease risk factors such as LDL and smoking, suggesting that primary preventive interventions targeted at weight reduction and improvement of insulin sensitivity may be particularly beneficial in this subset of the population.

Objective: Although recent studies have indicated that both orthostatic hypotension and orthostatic hypertension (OHTN) independently predict cardiovascular events, the underlying mechanisms are still debatable., Methods: A total of 700 nondiabetic adults (43% men, age 64 years) were examined by orthostatic blood pressure (BP) test, carotid artery ultrasonography, and biochemical tests including plasma fibrinogen and lipid profile. Multivariate-adjusted logistic regression was applied to assess association of intima-media thickness (IMT) and P-fibrinogen with orthostatic hypotension and OHTN. In addition, distribution of IMT and P-fibrinogen across quintiles of orthostatic systolic BP (SBP) response was analyzed., Results: Orthostatic hypotension and OHTN were found in 40 (5.7%) and 45 (6.4%) study participants, respectively. Both IMT [odds ratio (OR), 95% confidence interval (CI) per one-SD increment: 1.27, 1.01-1.60; P = 0.04] and P-fibrinogen (OR 1.44, 1.07-1.93; P = 0.02) were associated with orthostatic hypotension in a crude model. After adjustment relationship between orthostatic hypotension and IMT was slightly attenuated (OR 1.26, 0.96-1.65; P = 0.09) but was substantially unchanged in regard to P-fibrinogen (OR 1.45, 1.06-1.99; P = 0.02). In contrast, OHTN showed no association with either IMT or P-fibrinogen (adjusted OR 1.09, 0.78-1.52; P = 0.61, and 0.97, 0.70-1.34; P = 0.84, respectively). Distribution of IMT across quintiles of orthostatic SBP response was U-shaped, whereas that of fibrinogen was more linear but none of borderline quintiles (with pronounced hypertensive or hypotensive response) significantly differed from the middle quintiles in a fully adjusted model., Conclusion: In older nondiabetic adults only orthostatic hypotension seems to independently correlate with increased carotid atherosclerosis and systemic inflammation.

Objective: We assessed the relationship between pulse pressure and intermediate cardiovascular phenotypes in a middle-aged cohort with high prevalence of hypertension., Background: It has been suggested that central pulse pressure (cPP) is a better predictor of cardiovascular outcome than peripheral pulse pressure (pPP), particularly in the elderly. Yet, it is unclear if cPP provides additional prognostic information to pPP in younger individuals., Methods: In 535 individuals we assessed cPP and pPP as well as the intermediate cardiovascular phenotypes pulse wave velocity (PWV; SphygmoCor, Complior, PulsePen), carotid intima-media thickness (C-IMT; carotid ultrasound), left-ventricular mass index (LVMI; echocardiography) and urinary albumin : creatinine ratio (ACR). cPP was derived noninvasively from brachial blood pressure by pulse wave analysis (PWA; SphygmoCor) based on radial pulse wave tonometry and a validated transfer function., Results: The cohort contained 331 hypertensive participants of whom 84% were treated. The average age was 46 ± 16 years. When compared to pPP, cPP had stronger associations with PWV (r = 0.471 vs. r = 0.372; P < 0.01), C-IMT (r = 0.426 vs. r = 0.235; P < 0.01) and LVMI (r = 0.385 vs. r = 0.189; P < 0.01), but equal association with ACR (r = 0.236 vs. r = 0.226; P = n.s.). In contrast, after adjustment for age, mean arterial pressure, heart rate and hypertension status there was no significant difference between cPP and pPP for prediction of PWV (adjusted R, 0.399 vs. 0.413; P = 0.066), C-IMT (adjusted R, 0.399 vs. 0.413; P = 0.487) and LVMI (adjusted R, 0.181 vs. 0.170; P = 0.094) in multivariate analysis., Conclusion: In our middle-aged cohort with high prevalence of hypertension cPP is more closely correlated with cardiovascular phenotypes than pPP. When adjusted for relevant cofactors, however, cPP does not provide additional information beyond pPP.

Objectives: Essential hypertension is a complex condition whose cause involves the interaction of multiple genetic and environmental factors such as salt intake. Salt-inducible kinase 1 (SIK1) is a sucrose-nonfermenting-like kinase isoform that belongs to the AMPK (5' adenosine monophosphate-activated protein kinase) family. SIK1 activity is increased by high salt intake and plays an essential role in regulating the plasma membrane Na(+),K(+)-ATPase. The objective of this study was to examine whether SIK1 is present in vascular smooth muscle cells (VSMCs) and endothelial cells, whether it affects VSMC Na(+),K(+)-ATPase activity and whether human SIK1 (hSIK1) represents a potential candidate for blood pressure regulation., Methods: Localization of SIK1 was performed using immunohistochemistry, mRNA and western blot. Functional assays (Na(+),K(+)-ATPase activity) were performed in VSMCs derived from rat aorta. Genotype-phenotype association studies were performed in three Swedish and one Japanese population-based cohorts., Results: SIK1 was localized in human VSMCs and endothelial cells, as well as a cell line derived from rat aorta. A nonsynonymous single nucleotide polymorphism in the hSIK1 gene exon 3 (C→T, rs3746951) results in the amino acid change (15)Gly→Ser in the SIK1 protein. SIK1-(15)Ser was found to increase plasma membrane Na(+),K(+)-ATPase activity in cultured VSMC line from rat aorta. Genotype-phenotype association studies in three Swedish and one Japanese population-based cohorts suggested that T allele (coding for (15)Ser) was associated with lower blood pressure (P = 0.005 for SBP and P = 0.002 for DBP) and with a decrease in left ventricular mass (P = 0.048)., Conclusion: The hSIK1 appears to be of potential relevance within VSMC function and blood pressure regulation.

Aims/hypothesis: About 35% of individuals with type 2 diabetes develop persistent albuminuria, lose renal function, and are at increased risk for microvascular complications like diabetic nephropathy. Recent genome-wide association studies have identified the uromodulin locus (UMOD), encoding the most common protein in human urine to be associated with hypertension and also with chronic kidney disease (CKD). In the present study we examined the association of the common variant of the uromodulin (UMOD) gene with type 2 diabetic nephropathy and kidney function., Methods: UMOD variant rs13333226 was genotyped in a case-control material including 4888 unrelated type 2 diabetic individuals (n = 880 with and n = 4008 without nephropathy) from Sweden (Scania Diabetes Registry) using the ABI Real time TaqMan allelic discrimination assay., Results: The G allele of rs13333226 was associated with a decreased risk of nephropathy [odds ratio (OR) 0.80, 95% confidence interval (CI) 0.69-0.91, P = 0.001] after correction for confounding factors like age, sex, body mass index (BMI), blood pressure, kidney function, smoking and duration of diabetes. The same allele was also associated with a better kidney function [estimated glomerular filtration rate (eGFR), β = 0.117, P < 0.0001] and lower systolic blood pressure (β = -0.048, P = 0.013) in the overall study cohort., Conclusion/interpretation: The present study highlights that the common variant of the UMOD gene is protective against diabetic nephropathy susceptibility and also affects kidney function and blood pressure in patients with type 2 diabetes. However, the association with diabetic nephropathy was independent of blood pressure and kidney function.

Objective: Serum and glucocorticoid regulated kinase 1 (SGK1) expression is increased by aldosterone and is a key regulator of the amiloride-sensitive sodium channel (ENaC) in the distal nephron. We have previously shown that two SNPs in SGK1 (rs1057293 and rs1743966) are associated with blood pressure variation and blood pressure progression in the general population. Therefore, we tested the association of these variants with ischaemic stroke., Methods: Using logistic regression, we analysed rs1057293 and rs1743966 for association with ischaemic stroke in two independent age-matched and sex-matched case-control groups from the twin cities of Lund (cases n=1837 and controls n=947) and Malmö (cases n=888 and controls n=893) in the Scania region of southern Sweden., Results: In additive models adjusted for hypertension, smoking and diabetes, the major allele (G) of rs1057293 was associated (odds ratio, 95% confidence interval; P value) with ischaemic stroke with similar effect size in both studies; in Lund (1.35, 1.11-1.64; P=0.002) and Malmö (1.30, 1.03-1.65; P=0.027). When the two studies were pooled, the overall association was 1.32, 1.14-1.52; P<0.001. The major allele of rs1743966 (A), which was in linkage disequilibrium with rs1057293, showed a similar trend as rs1057293 G-allele but with slightly weaker effect size and P value., Conclusion: In two independent but ethnically similar populations, we observed an association between genetic variants in SGK1 and ischaemic stroke. Interestingly, the association seems to be at least partially independent of blood pressure. This could imply that cerebrovascular ENaC or other SGK1-regulated proteins may be of importance for development of ischaemic stroke., (© 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins)

Background: As recently pinpointed by a genome-wide association study the serine/threonine kinase 39 (STK39) is a candidate gene for hypertension. This kinase is strongly implicated in sodium reabsorption by the kidney through its modulating effect on furosemide-sensitive and thiazide-sensitive channels. The aim of our study was to test the effects of the STK39 rs35929607A>G polymorphism on blood pressure (BP) levels and the prevalence and incidence of hypertension in middle-aged Swedes participating in two urban-based surveys in Malmö (Sweden)., Methods: The rs35929607A>G polymorphism was genotyped in 5634 participants included in the cardiovascular cohort of the 'Malmö Diet and Cancer-cardiovascular arm' (MDC-CVA) study and successively in 17 894 participants of the 'Malmö Preventive Project' (MPP) both at baseline and at reinvestigation after a mean of 23 years. The effect of the same single nucleotide polymorphism on salt sensitivity was tested in 39 participants of the Salt Reduction to Avoid Hypertension study., Results: Both before and after adjustment for covariates, the functional rs35929607A>G polymorphism was associated with higher SBP and DBP values in the MDC-CVA, but not in the MPP. In both surveys, the polymorphism was associated with hypertension prevalence; after adjustment using the autosomal-dominant model, the odds ratio for hypertension ranged between 1.077 (MPP at baseline) and 1.151 (MDC-CVA) with P-value less than 0.05. After stratification for sex, the results remained statistically significant in women, but not in men. Carriers of the G-allele displayed an increase in salt sensitivity., Conclusion: Our results from two large cohort studies support previous evidence about the association of the STK39 rs35929607A>G variant with hypertension, especially in women. If further confirmed in successive studies, owing to its pivotal role in sodium reabsorption at the renal tubule level, STK39 might prove to be a suitable target for antihypertensive therapy. The greater effect of the STK39 rs35929607A>G polymorphism in women with respect to men deserves further investigation.

Objective: The capability of the protein NEDD4L to reduce renal tubular expression of epithelial Na+ channel (ENaC) is influenced by a functional rs4149601 G→A NEDD4L polymorphism. As diuretics and β-blockers inhibit renal sodium reabsorption and renin release, respectively, we hypothesized that the β-blocker or diuretic-induced blood pressure reduction and prevention of cardiovascular disease would be greater in patients with the highest ENaC expression (rs4149601 G-allele), whereas there would be no such genetically mediated differences in treatment efficacy among patients treated with the vasodilator diltiazem., Methods: We related rs4149601 status to 6-month blood pressure reduction and risk of cardiovascular events in 5152 hypertensive patients (DBP ≥ 100 mmHg) from the Nordic Diltiazem Study (NORDIL) randomized to either β-blocker and/or diuretic-based treatment or diltiazem-based treatment., Results: In patients on β-blocker or diuretic monotherapy, carriers of the G-allele had greater SBP reduction (19.5 ± 16.8 vs. 15.0 ± 19.3 mmHg, P < 0.001) and DBP reduction (15.4 ± 8.3vs. 14.1 ± 8.4 mmHg, P = 0.02) and during 4.5 years of follow-up among patients randomized to β-blockers and/or diuretics, carriers of the G-allele had greater protection from cardiovascular events [relative risk (RR) = 0.52, 95% confidence interval (CI) = 0.36-0.74, P < 0.001] as compared to AA homozygotes. Within the diltiazem group, there was no difference in blood pressure reduction or risk of cardiovascular events according to genotype., Conclusion: The functional NEDD4L rs4149601 polymorphism influences the efficacy of β-blocker and/or diuretic-based antihypertensive treatment both in terms of blood pressure reduction and cardiovascular disease protection, whereas diltiazem-based antihypertensive treatment efficacy is not influenced by this NEDD4L polymorphism.

Objective: To investigate the determinants and consequences of orthostatic hypotension in the middle-aged segment of the general population., Methods: A population of 5722 men aged 52.6 +/- 3.6 years, previously included in the Malmö Preventive Project (n = 22 444 men), was re-screened after 5.6 +/- 1.0 years and thereafter followed up over a period of 19.6 +/- 5.3 years., Results: At re-screening, 566 (9.9%) participants were found to have orthostatic hypotension according to international consensus criteria, of these 365 (64.5%) demonstrated systolic impairment only. In a multivariate adjusted logistic regression model, age, low BMI, hypertension, increased heart rate, antihypertensive treatment, diabetes and current smoking independently determined orthostatic hypotension, but systolic impairment also showed association with higher pulse pressure and reduced glomerular filtration rate. In a multivariate adjusted Cox proportional hazard model, men with orthostatic hypotension demonstrated a higher risk of incident coronary event, stroke and all-cause mortality than men without orthostatic hypotension. Systolic impairment was a better predictor of all studied endpoints than were the combined criteria of orthostatic hypotension. Moreover, participants with orthostatic hypotension at both baseline and re-screening showed the highest risk of any adverse event (hazard risk 1.76, 95% confidence interval 1.28-2.43, P = 0.001), exceeding the risk predicted by orthostatic hypotension at re-screening only (hazard risk 1.22, 95% confidence interval 1.07-1.38, P = 0.003)., Conclusion: Orthostatic hypotension may be found in up to 10% of middle-aged men and correlates with well known cardiovascular risk factors such as hypertension, smoking, diabetes and kidney failure. Orthostatic impairment seems to constitute an independent cardiovascular risk factor and may be practically estimated by systolic reaction only. As orthostatic reaction may vary over time, repeated measurements or more accurate diagnostic methods are recommended to identify high-risk patients with persistent orthostatic hypotension.

Background: CYP2J2 is responsible for the production of 5,6 8,9 11,12 and 14,15-epoxyeicosatrienoic acids, vasodilator and anti-inflammatory substances. It is abundantly expressed in human heart and also present in kidney and vasculature. Carriers of a common polymorphism, the CYP2J2 -50G>T, rs890293, have reduced expression of CYP2J2 mRNA level in the heart putatively through the interference with a binding site for a transcription factor with consequently reduced circulating levels of CYP2J2 epoxygenase metabolites in vivo., Aim: The aim of the present study was to evaluate the effect of this functional polymorphism on blood pressure (BP) levels, hypertension prevalence, and risk of incident cardiovascular events in middle-aged Swedes., Methods: The CYP2J2 polymorphism was genotyped in 5740 participants of the cardiovascular cohort of the 'Malmö Diet and Cancer' study. The incidence of cardiovascular events (coronary events, n = 261; ischemic stroke, n = 185) was monitored over 10 years of follow-up., Results: In the whole population the polymorphism had no effect on BP and hypertension prevalence and no interaction was found between the polymorphism and sex, age or body mass index. Before and after adjustment for major cardiovascular risk factors, the hazard ratio for incident ischemic stroke and coronary events was not significantly different in carriers of different genotypes., Conclusions: Our data do not support a major role for the CYP2J2 -50G>T variant in determining BP level and incident ischemic events. Other studies are needed to elucidate if other polymorphisms in the same gene could have a role in BP homeostasis or incidence of cardiovascular events.

Objective: We tested whether men and women in the European Society of Hypertension (ESH) high normal and normal blood pressure (BP) categories, all included in the the Seventh Joint National Committee (JNC 7) prehypertension group, share similar metabolic characteristics and whether they differ from men and women with optimal BP (<120/80 mmHg)., Methods: BP (multiple measurements with a standardized automatic device), insulin sensitivity (euglycaemic clamp), oral glucose tolerance test (OGTT), carotid intima-media-thickness (IMT, echo), family history (questionnaire), physical activity (accelerometer), and anthropometrics (bioimpedance) were evaluated in the 1384 healthy European individuals ranging from 30-60 years participating in the multicentre study Relationship between Insulin Sensitivity and Cardiovascular disease (RISC)., Results: BMI and waist-to-hip ratio were higher (both P < 0.05 adjusted for age and recruiting centre) in men and women with high normal (but not normal) BP with respect to optimal BP. Similarly, in women (after adjustment for study centre, age, physical activity, and waist), serum triglycerides and carotid IMT were higher in those with high normal (but not normal) BP; moreover, in this group there was a higher prevalence of glucose-intolerance (21.8 versus 9.7%, P = 0.02) and insulin sensitivity tended to be lower (P = 0.07). Insulin sensitivity and diastolic blood pressure were weakly related variables displaying a nonlinear association with a threshold below the normal BP values and no interaction with family history of hypertension., Conclusion: The JNC 7 category prehypertension identifies a dishomogeneous group of individuals whereas the ESH classification, particularly in women, was more accurate in identifying both the predisease and the healthy phenotype. Insulin resistance is not a major characteristic of the condition of prehypertension.

Objective: To test whether a previously hypertension-linked 23 cM region on chromosome 2 is linked to the metabolic syndrome (MetS) or its individual components, and whether a common I/D polymorphism of the adrenergic receptor 2b (ADRA2B) gene, mapping in that region, is associated with the same traits., Methods: We conducted fine mapping of the hypertension-linked region on chromosome 2 spanning between 107 and 130 cM using 11 informative polymorphic markers in 260 healthy white siblings belonging to 118 nuclear families. Variance-component linkage analysis was performed for each MetS component and a composite sum of MetS phenotypes as quantitative trait after adjustment for significant covariates using 'Solar software package'. Successively, the I/D polymorphism of the ADRA2B gene was genotyped in 5283 patients in the Malmö Diet and Cancer-cardiovascular arm, seeking for association with the MetS using standard definitions and separately, with its individual components., Results: For 24-h pulse pressure and waist/hip ratio, LOD [logarithm of the odds (to the base 10)] scores of more than two were found between 107 and 122 cM on chromosome 2. For the composite sum of MetS phenotypes, LOD score of more than 1 was found between 116 and 120 cM. There was no difference between carriers and noncarriers of the D-allele of the ADRA2B gene in MetS prevalence but D-carriers were associated with significantly higher levels of diastolic blood pressure., Conclusion: Our results suggest that chromosome 2 could harbor one or more genes implied in blood pressure homeostasis and MetS development. The ADRA2B I/D polymorphism is not consistently associated with MetS and metabolic/anthropometric parameters but with diastolic blood pressure in an urban-based population of middle-aged Swedes.

Objectives: Prevalence and determinants of orthostatic hypotension remain largely unexplored in younger individuals without significant burden of chronic diseases., Methods: We investigated frequency and main associations of impaired orthostatic response in a cohort of 469 middle-aged hypertensive patients and 453 of their normotensive first-degree relatives., Results: 13.4% of hypertensive and 5.5% of normotensive study participants were found to have orthostatic hypotension. In a backward logistic regression the following determinants of orthostatic hypotension were identified: sex [female, odds ratio (OR) 2.45, 95% confidence interval (CI) 1.14-5.25, P=0.022], reduced glomerular filtration rate [OR (per ml/min/1.73 m2) 0.97, 95% CI 0.94-0.99, P=0.002], systolic [OR (per mmHg) 1.02, 95% CI 1.00-1.05, P=0.047] and diastolic blood pressure [OR (per mmHg) 1.04, 95% CI 1.00-1.09, P=0.033], and antihypertensive treatment (OR 0.41, 95% CI 0.18-0.93, P=0.034). In hypertensive patients use of angiotensin-converting enzyme inhibitors was related to lower orthostatic hypotension frequency. Percentage of orthostatic hypotension-positive patients in the highest blood pressure stratum (> or = 160 mmHg) decreased from 20.2 to 7.6, when diagnostic criteria of orthostatic hypotension were adjusted for mean systolic orthostatic reaction (2 SD value: 30 mmHg) . During follow-up (t=6.6 years) individuals with impaired orthostatic response showed a trend towards increased total mortality (OR 2.16, 95% CI 0.97-4.80, P=0.06) in a crude model., Conclusion: Prevalence of orthostatic hypotension in hypertensive patients is higher than in their normotensive first-degree relatives. Independently of age, sex, and elevated blood pressure, orthostatic hypotension may be additionally determined by impaired renal function. Antihypertensive treatment seems to protect from orthostatic hypotension, in particular, use of angiotensin-converting enzyme inhibitors in hypertensive patients. The diagnostic criteria of orthostatic hypotension may need adjustment for initial supine systolic blood pressure to increase clinical accuracy. The prognostic value of impaired orthostatic response regarding risk of cardiovascular disease and mortality remains uncertain and requires further studies.

Objective: We tested whether two single-nucleotide polymorphisms (SNPs) (rs2383207 and rs10757278), previously strongly associated with myocardial infarction, are independently associated with stroke and coronary events in patients with hypertension., Methods: The Nordic Diltiazem study compared the effects of calcium antagonist and beta-blocker or diuretic-based antihypertensive treatment on cardiovascular events in 10 881 patients with hypertension, of whom 5262 patients provided DNA for the present study. We related SNPs rs2383207 and rs10757278 to stroke and to myocardial infarction and coronary revascularizations (coronary events) using crude and multivariate adjusted Cox proportional hazards models., Results: The G-allele of both SNPs predicted coronary events in crude recessive models [hazard ratios = 1.36, 95% confidence interval (CI) = 1.04-1.79, P = 0.02 for rs10757278 and hazard ratios = 1.40, 95% CI = 1.08-1.81, P = 0.01 for rs2383207] as well as after adjustment for classical cardiovascular risk factors. The G-allele of both SNPs predicted incident stroke in crude additive models [rs2383207 hazard ratios = 1.25 (95% CI = 1.02-1.53), P = 0.04 and rs10757278 hazard ratios = 1.34 (95% CI = 1.09-1.65), P = 0.006], as well as after adjustment for classical cardiovascular risk factors and after additional adjustment for prevalent and incident coronary events, atrial fibrillation, ischemic heart disease and congestive heart failure. As was the case for coronary events, the excess genetic risk of stroke was driven by subjects homozygous for the risk allele., Conclusion: Genetic variation at the CDKN2A/CDKN2B locus predicts stroke in hypertensive patients. The genetic association with stroke is independent of classical cardiovascular risk factors and of all prevalent and incident coronary events, suggesting that gene variation at this locus promotes either atherosclerosis or another disease mechanism that is common to both coronary and cerebrovascular disease.

Objectives: The aim of this study was to examine whether three main definitions of the metabolic syndrome (MetS)--WHO, National Cholesterol Education Program--Adult Treatment Panel III and International Diabetes Federation--identify the same individuals and are able to predict incident myocardial infarction (MI) in families with essential hypertension., Methods: The tested definitions were prospectively related to data on MI in a cohort of approximately 1700 individuals with overt essential hypertension and their normotensive first-degree relatives., Results: At baseline, 616 participants had MetS, yet only 209 of them (33.9%) were identified by all definitions, and compatibility rate for each pair of definitions was approximately 50%. During follow-up (Tmean approximately 6.6 years) 53 participants developed MI and they were generally older and more dysmetabolic than the rest of the cohort. There were also more men, smokers and diabetic individuals in this group. After adjustment for all conventional cardiovascular risk factors, including hypertension and diabetes, only the National Cholesterol Education Program definition could predict the increased risk of MI [odds ratio (OR) = 2.2, confidence interval (CI) = 1.2-4.0, P = 0.01]. Among individual MetS components, incident MI was independently associated with three of them: low high-density lipoprotein-cholesterol (OR = 2.03, CI = 1.09-3.78, P = 0.025) insulin resistance (OR = 2.02, CI = 1.08-3.78, P = 0.028) and increased albumin excretion rate (OR = 1.24, CI = 0.99-1.55, P = 0.060)., Conclusion: The presence of MetS in hypertensive and genetically hypertension prone individuals may signal the increased risk of future MI. However, only the National Cholesterol Education Program criteria appear to have a sufficient predictive accuracy.

The aim of this study was to evaluate the determinants of kidney function and the role of heritable factors in a sample of 249 siblings free from known cardiovascular disease and without antihypertensive drugs belonging to 110 families. Four different measures and estimates of kidney function were considered. Blood pressure was recorded during 24 h by ambulatory blood pressure monitoring. Heritability was estimated with and without adjustment for significant covariates.In multivariate analysis, in addition to age, sex, BMI, HDL-cholesterol, 24-h systolic and mean blood pressure, systolic nocturnal blood pressure dipping resulted independently related to serum creatinine, estimated Cockcroft-Gault-creatinine clearance and estimated by the modification of diet in renal disease-glomerular filtration rate. After full adjustment, the heritability values were 51% for the measured creatinine clearance (P < 0.01), 58% for the estimated Cockcroft-Gault-creatinine clearance (P < 0.001), 40% for the estimated by the modification of diet in renal disease-glomerular filtration rate (P < 0.001), but 8% (P = 0.34) for serum creatinine.Our data confirm that kidney function is partially under genetic control and that genetic variants of importance for this trait could be mapped. The association of the circadian rhythm of blood pressure with kidney function in this sample deserves further investigation.

Background: Job strain and the Arg389Gly polymorphism in the adrenergic beta1-receptor gene have been linked to hypertension. We aimed to study whether there is an interaction between the Arg389Gly polymorphism and job strain and its components (job demand and decision latitude) in relation to blood pressure., Methods: From the Malmö Diet and Cancer population cohort, 6095 individuals were randomly selected to be followed regarding cardiovascular risk factors. From this group, employed individuals with baseline data regarding work characteristics were included (1338 men and 1707 women). Determination of adrenergic beta1-receptor Arg389Gly polymorphism was possible in 1271 men and 1601 women, and these individuals formed the study group., Results: Men with the combination of Arg389Arg and job strain were more often on antihypertensive medication (P = 0.04), whereas blood pressure was not significantly higher, in comparison with those without both of these two factors. The interaction term genotype x job strain was borderline significant for systolic blood pressure (P = 0.07) after adjustments for age, country of birth, and job status. The demand score showed significant interaction in men with genotype (P = 0.01 for systolic blood pressure and P = 0.009 for diastolic blood pressure) after adjustments for age, country of birth, job status, antihypertensive treatment, and BMI. Men with the Gly389 allele had lower blood pressure with increasing demand score (P = 0.001), whereas men homozygous for the Arg389 allele had lower blood pressure with increasing latitude score (P = 0.03). In women, those with job strain tended to have higher blood pressure than those without job strain, among carriers of Arg389Arg and Arg389Gly genotype., Conclusion: Men with job strain and the Arg389Arg polymorphism were more often on antihypertensive treatment than other men. Significant interactions between the Arg389Gly polymorphism and aspects of job stress are described, but the absolute blood pressure differences are small. Considering the commonness of the polymorphism, stress, and hypertension further studies are indicated.

Among the common complex diseases, hypertension has been particularly unlucky in the recent surge of positive results from genome-wide association studies. We summarize the evidence that would support continuing the effort in the hunt for a genetic basis for hypertension. The problems facing the genetic studies for hypertension are not unique, but phenotypic characterization, heterogeneity and high prevalence make it a special case requiring a more individualized approach. We argue that, even in the presence of a strong environmental component to hypertension risk, the common disease/common variant model is relevant for hypertension and discuss the issues involved in designing a genome-wide association study for hypertension. It is likely that the individual odds ratios for disease variants will be less than 1.3 and, although individually these effect sizes are minor, the combination of even a few such common polymorphisms can have substantial population attributable risks. The identification of hypertension gene variants should provide new insight into the disease susceptibility, progression and severity. This will lead to the identification of potential targets for lifestyle and pharmacological interventions, with the ultimate goal of improving prevention, diagnosis and treatment.

Background: Job strain (high demands and low decision latitude) and the DD genotype of an I/D polymorphism in the adrenergic alpha2B-receptor have been associated with hypertension, respectively. We hypothesized that the I/D polymorphism interacts with external stress, such as job strain, in the development of hypertension., Methods: A sample of 3045 employed men and women from the population cohort of Malmö Diet and Cancer Study, n = 28 098, with baseline data regarding work characteristics and cardiovascular risk factors, were genotyped for the adrenergic alpha2B-receptor I/D polymorphism. This was possible in 1302 men and 1662 women, and these individuals formed the study group., Results: The age-adjusted systolic blood pressure (SBP) for men with the DD polymorphism and job strain (n = 26) was 147.0 +/- 3.4 mmHg, whereas for men with the DD polymorphism but without job strain (n = 184), the SBP was 138.2 +/- 1.4 mmHg (P = 0.018). Similar findings were made regarding diastolic blood pressures (DBP) in men. Job strain and the I/D polymorphism in the adrenergic alpha2B-receptor gene significantly interacted in men [P = 0.008 for SBP, P = 0.03 for DBP, adjusted for age, body mass index, occupational status and nationality (Model 1)]. Increasing latitude score was inversely correlated with SBP (beta -0.17, P = 0.03, Model 1) in DD men, but not in men with the I-allele; interaction significance for genotype x latitude score, P = 0.02 for SBP (Model 1). In women, there were no significant interactions between genotype and work characteristics (P = 0.32 for SBP, and P = 0.60 for DBP)., Conclusion: For the first time, a significant interaction between a genetic factor and work environment, resulting in elevated blood pressures, has been described.

Objective: Obstructive sleep apnoea (OSA) confers a risk of hypertension and cardiovascular complications. Both the renin-angiotensin-aldosterone system and OSA are important determinants of blood pressure, but it is not fully known how they interact. The aim of this study was to explore the interaction between the angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism and OSA in the association with hypertension., Design: A community-based, case-control design with hypertensive patients in primary care (n = 157) and normotensive population controls (n = 181)., Methods: All subjects underwent ambulatory polysomnography during one night. OSA was defined by a minimum of 10 apnoea/hypopnoea events per hour. Office blood pressure was measured and hypertension status was assessed. The genotypes were determined using polymerase chain reaction., Results: An interaction analysis including sex, ACE I/D polymorphism (DD and ID versus II), and OSA identified a significant interaction between OSA and the ACE I/D polymorphism: odds ratio (OR) 6.3, 95% confidence interval (CI) 1.8-22.5, P = 0.004 as well as between OSA and sex: OR 3.3, 95% CI 1.1-9.6, P = 0.033. OSA was significantly associated with hypertension in men but not in women., Conclusion: The interaction between the ACE gene I/D polymorphism and OSA appears to be an important mechanism in the development of hypertension, particularly in men.

Objective: The effect of salt restriction on blood pressure is under intense debate. We tested the effect of 100 mmol salt reduction on ambulatory blood pressure (ABP) in 46 Swedish individuals, 39 of whom completed the study, using a double-blind, placebo-controlled, cross-over design. Furthermore, we tested whether the basal plasma concentration of renin or N-terminal atrial natriuretic peptide (Nt-proANP) predict the degree of salt sensitivity., Methods: Participants received all meals and drinks with a total daily NaCl content of 50 mmol during 8 weeks. In addition, NaCl capsules (100 mmol/day) and corresponding placebo capsules were administered for 4 weeks each in random order. ABP after high-salt intake (150 mmol/day) was compared with ABP after low-salt intake (50 mmol/day). Salt sensitivity was defined as the difference between 24-h systolic ABP at the high-salt versus the low-salt periods. Baseline renin and Nt-proANP were related to salt sensitivity., Results: Lowering of salt intake from 150 to 50 mmol/day induced significant blood pressure reductions (mean reduction, 95% confidence interval) in systolic and diastolic 24-h ABP (5.8, 3.4-8.2 and 2.6, 0.91-4.4 mmHg), daytime ABP (5.5, 2.9-8.1 and 2.3, 0.42-4.1 mmHg) and night-time ABP (6.4, 3.5-9.3 and 3.4, 1.4-5.5 mmHg). Baseline ln(renin) correlated inversely with salt sensitivity (r = -0.50, P = 0.001) whereas baseline ln(Nt-proANP) correlated directly (r = 0.33, P = 0.04)., Conclusion: Lowering of salt intake with 100 mmol/day induces clinically relevant ABP reductions. Renin and Nt-proANP, measured with individuals on their habitual diet, could be useful biomarkers to identify individuals with the greatest blood pressure-lowering benefit from reduced salt intake.

Objective: A common threonine481serine polymorphism (T481S) has been shown in vitro to strongly activate the chloride channel Kb (CLC-Kb) expressed in the kidney, and the 481S allele has been associated with human hypertension. The study aim was to evaluate the association of the T481S polymorphism with blood pressure (BP) levels and the BP progression rate in Swedes., Design and Methods: The cardiovascular cohort of the Malmö Diet and Cancer (MDC) study is a population surveyed in 1991-1996 (n=6103, DNA available on n=6055), 53% of whom had also been examined 11 +/- 4.4 years earlier in the Malmö Preventive Project (MPP). Hypertension was defined as having BP above 140/90 mmHg or being on antihypertensive therapy (AHT). Carriers of one or two copies of the 481S allele were compared with T481T homozygotes (noncarriers)., Results: Among individuals without AHT in the MDC study (n=4988) there was no difference between carriers (n=1164, 23%) and noncarriers (n=3824, 77%) in systolic BP (139.3 +/- 8.3 vs 139.2 +/- 8.3 mmHg, P = 0.82) or diastolic BP (86.0 +/- 9.1 vs 86.0 +/- 9.2 mmHg, P = 0.95). In subjects free from AHT at the MPP and MDC studies (n=2627) there was no difference between carriers (n=607, 23%) and noncarriers (n=2020, 77%) in progression of systolic BP (2.1 +/- 2.6 vs 2.0 +/- 2.8 mmHg/year, P = 0.72) or diastolic BP (0.57 +/- 1.4 vs 0.58 +/- 1.6 mmHg/year, P = 0.85) from MPP to MDC. Multivariate analysis gave no support of interaction between the CLC-Kb T481S polymorphism, gender, age or body mass index regarding their effect on BP., Conclusion: Our data do not support a role of the CLC-Kb T481S polymorphism in BP regulation in Swedes.

Objective: The aim of this study was to estimate the heritability of 24-h ambulatory blood pressure and office blood pressure phenotypes in Swedish families., Methods: We measured ambulatory and office blood pressure in 260 siblings without antihypertensive treatment from 118 families. Blood pressure heritability was estimated using standard quantitative genetic variance component analysis implemented in the 'SOLAR' software package after adjustment for significant covariates., Results: Heritability values were significant for night-time systolic (37%), diastolic (32%) and mean (32%) ambulatory blood pressure (P < 0.05 for all). During daytime, systolic ambulatory blood pressure was significantly heritable (33%, P < 0.05). Twenty-four-hour systolic (30%) and diastolic (29%) ambulatory blood pressure also had significant values of heritability (P < 0.05). Pulse pressure ambulatory blood pressure was significantly heritable over 24 h (63%, P < 0.01), during daytime (53%, P < 0.01) and at night (34%, P < 0.05). None of the office blood pressure phenotypes had a significant heritability., Conclusions: We conclude that ambulatory blood pressure, in particular at night, seems better than office blood pressure to capture the heritable part of blood pressure, suggesting that ambulatory blood pressure may be a more exact estimate of an individual's true blood pressure. Genetic studies using ambulatory blood pressure as the phenotype are likely to be more powerful than those using office blood pressure. The high heritability of pulse pressure ambulatory blood pressure indicates that variation in arterial stiffness in subjects free from antihypertensive medication is strongly affected by genetic factors.

Objective: This study explored whether the Pro12Ala polymorphism in the peroxisome proliferator-activated receptor-gamma (PPARgamma) is associated with blood pressure in subjects with type 2 diabetes., Design: A community-based, cross-sectional observation study., Setting: Primary care., Patients: One hundred and ninety-two men and 192 women with type 2 diabetes who consecutively underwent annual follow-up., Main Outcome Measure: The PPARgammaPro12Ala genotype was determined by polymerase chain reaction-based techniques. Associations between genotype and blood pressure were analysed by linear regression and expressed as differences in blood pressure (delta) with 95% confidence interval (CI)., Results: The mean systolic blood pressure and the diastolic blood pressure were 160 mmHg (standard deviation = 22.8) and 84 mmHg (standard deviation = 9.6), respectively. Subjects with Pro/Ala (24%) or Ala/Ala (2%) had lower diastolic blood pressure (delta = 2.8; 95% CI, 0.6-5.0) when adjusted for age and gender compared with Pro/Pro subjects (74%). This association was restricted to men (delta = 4.4; 95% CI, 1.3-7.4), who also had a borderline significant difference in systolic blood pressure (delta = 6.9; 95% CI, -0.8 to 13.8). In men the difference in diastolic blood pressure remained after adjustment for age, body mass index, serum triglycerides, serum insulin and haemoglobin A(1c) (delta = 4.6; 95% CI, 1.1-8.1). A subanalysis of normotensive men (n = 100) confirmed the difference associated with the Pro12Ala polymorphism in diastolic blood pressure (delta = 5.2; 95% CI, 0.6-10.0)., Conclusions: The common Pro12Ala polymorphism in PPARgamma is associated with lower diastolic blood pressure in male subjects with type 2 diabetes.

Objective: To study the association between polymorphisms in the angiotensin converting enzyme (ACE) gene and angiotensinogen (AGT) gene and hypertension and/or type 2 diabetes in a community population., Patients and Methods: The insertion (I)/deletion (D) polymorphism of the ACE gene and the M235T polymorphism of the AGT gene were genotyped in 773 nondiabetic individuals with hypertension, 193 normotensive patients with type 2 diabetes, 243 patients with type 2 diabetes and hypertension, and in 820 normotensive control individuals identified in a community-based study., Results: The DD genotype was associated with hypertension in individuals less than 70 years [odds ratio (OR) = 1.54, confidence interval (CI) = 1.09-2.18] and remained so when patients with type 2 diabetes were excluded from the analysis (OR = 1.45, CI = 1.01-2.09). The strongest association was with the combination of type 2 diabetes and hypertension (OR = 2.19, CI = 1.09-4.38). There was no association with type 2 diabetes without hypertension. No association was observed between the M235T variant or the 3'-microsatellite polymorphism of the AGT gene and hypertension., Conclusion: The D-allele of the ACE gene ID polymorphism increases susceptibility to hypertension, particularly when associated with type 2 diabetes. No association was observed between the M235T variant or 3'-microsatellite polymorphism of the AGT gene and hypertension.

Objective: To study whether heredity for hypertension influences intra-uterine growth and the relationship between fetal growth and adult blood pressure., Design: Five-year prospective follow-up study with retrospective collection of data on size at birth and gestational age from obstetric records., Setting: Centre of preventive medicine in Malmo, Sweden., Subjects: Thirty normotensive men with and 27 without heredity for hypertension were investigated in 1990, and the majority (n = 28 and n = 20, respectively) in 1995 also., Main Outcome Measures: Two measures of intra-uterine growth were compared between the groups and related to adult systolic blood pressure: the birth weight deviation from the expected birth weight based on ultrasonically derived intra-uterine growth curves, and the degree of thinness at birth (ponderal index = weight/length3)., Results: The birth weight deviation in men with heredity for hypertension differed significantly from that in men without such heredity (%) (-6.9+/-12.0 versus +7.3+/-18.4; P = 0.002). Ponderal index was somewhat lower in the men with than in those without heredity for hypertension, but the difference did not reach statistical significance (kg/m3) (25.9+/-2.6 versus 27.0+/-2.2; P = 0.08). In the group with heredity for hypertension, systolic blood pressure correlated inversely with ponderal index both in 1990 (r = -0.44; P = 0.01) and 1995 (r = -0.49; P = 0.009), and the 5-year increase in systolic blood pressure correlated inversely with the birth weight deviation (r = -0.38; P = 0.04). No such correlations were found in the group without heredity for hypertension., Conclusion: Our results suggest that genetic factors contributing to the development of hypertension may influence intra-uterine growth.