Coffee consumption and calcified atherosclerotic plaques in the coronary arteries: The NHLBI Family Heart Study.

BACKGROUND & AIMS: While a recent meta-analysis of prospective studies reported that coffee consumption is associated with a lower risk of cardiovascular disease mortality, limited and inconsistent data are available on the relation of coffee intake with subclinical disease. Thus, the aim of the present study was to see the association of coffee consumption with the prevalence of atherosclerotic plaque in the coronary arteries in NHLBI Family Heart Study. METHODS: In a cross-sectional design, we studied 1929 participants of the NHLBI Family Heart Study without known coronary heart disease. Coffee consumption was assessed by a semi-quantitative food frequency questionnaire and coronary-artery calcium (CAC) was measured by cardiac computed tomography. We defined prevalent CAC as an Agatston score of ≥100 and used generalized estimating equations to calculate prevalence ratios of CAC as well as a sensitivity analysis at a range of cutpoints for CAC. RESULTS: Mean age was 56.7 years and 59% of the study subjects were female. In adjusted analysis for age, sex, BMI, smoking, alcohol, physical activity, field center, and energy intake, prevalence ratio (95% CI) for CAC was 1.0 (reference), 0.92 (0.57-1.49), 1.34 (0.86-2.08), 1.30 (0.84-2.02), and 0.99 (0.60-1.64) for coffee consumption of almost never, <1/day, 1/day, 2-3/day, and ≥4 cups/day, respectively. In a sensitivity analysis, there was no evidence of association between coffee consumption and prevalent CAC when CAC cut points of 0, 50, 150, 200, and 300 were used. CONCLUSIONS: These data do not provide evidence for an association between coffee consumption and prevalent CAC in adult men and women.

Association of dietary omega-3 fatty acids with prevalence of metabolic syndrome: the National Heart, Lung, and Blood Institute Family Heart Study.

BACKGROUND & AIMS: Metabolic syndrome (MetS), characterized by abdominal obesity, atherogenic dyslipidemia, elevated blood pressure, and insulin resistance is a major public health concern in the United States. Omega-3 fatty acids have been relatively well studied in relation to many individual cardiovascular risk factors; however, their effects on MetS are not well established. METHODS: We conducted a cross-sectional study consisting of 4941 participants from the National Heart, Lung, and Blood Institute (NHLBI) Family Heart Study to assess the relation of dietary omega-3 fatty acids with the prevalence of MetS. Omega-3 intake was assessed using a food frequency questionnaire and we used generalized estimating equations to estimate adjusted odds ratios for prevalent MetS. RESULTS: Our study population had a mean age (SD) of 52.1 (13.9) years and 45.9% were men. The mean (SD) of dietary omega-3 fatty acids was 0.25 g/day (0.27). From the lowest to the highest quintile of dietary omega-3 fatty acids, multivariable adjusted ORs (95% CI) for MetS were 1.00 (ref), 0.90 (0.72-1.13), 1.03 (0.82-1.28), 0.94 (0.74-1.18), and 0.99 (0.77-1.25), respectively. In a secondary analysis, neither fish consumption nor dietary alpha-linolenic acid was associated with MetS. CONCLUSIONS: Our findings do not support an association between dietary omega-3 fatty acids and MetS in a large US population.

The epithelial sodium channel γ-subunit gene and blood pressure: family based association, renal gene expression, and physiological analyses.

Variants in the gene encoding the γ-subunit of the epithelial sodium channel (SCNN1G) are associated with both Mendelian and quantitative effects on blood pressure. Here, in 4 cohorts of 1611 white European families composed of a total of 8199 individuals, we undertook staged testing of candidate single-nucleotide polymorphisms for SCNN1G (supplemented with imputation based on data from the 1000 Genomes Project) followed by a meta-analysis in all of the families of the strongest candidate. We also examined relationships between the genotypes and relevant intermediate renal phenotypes, as well as expression of SCNN1G in human kidneys. We found that an intronic single-nucleotide polymorphism of SCNN1G (rs13331086) was significantly associated with age-, sex-, and body mass index-adjusted blood pressure in each of the 4 populations (P<0.05). In an inverse variance-weighted meta-analysis of this single-nucleotide polymorphism in all 4 of the populations, each additional minor allele copy was associated with a 1-mm Hg increase in systolic blood pressure and 0.52-mm Hg increase in diastolic blood pressure (SE=0.33, P=0.002 for systolic blood pressure; SE=0.21, P=0.011 for diastolic blood pressure). The same allele was also associated with higher 12-hour overnight urinary potassium excretion (P=0.04), consistent with increased epithelial sodium channel activity. Renal samples from hypertensive subjects showed a nonsignificant (P=0.07) 1.7-fold higher expression of SCNN1G compared with normotensive controls. These data provide genetic and phenotypic evidence in support of a role for a common genetic variant of SCNN1G in blood pressure determination.

Influence of saturated fat and linolenic acid on the association between intake of dairy products and blood pressure.

Data on the association between dairy consumption and blood pressure have been inconsistent. We sought to examine the relation between dairy consumption and prevalent hypertension (HTN) among 4797 participants of the National Heart, Lung, and Blood Institute Family Heart Study. We used generalized estimating equations to estimate prevalence odds ratios of HTN across categories of dairy consumption. From the lowest to the highest sex-, age-, and energy-adjusted quartile of dairy consumption, there was an inverse association between dairy intake and prevalent HTN: odds ratios (95% CIs) were 1.0 (reference), 0.82 (0.64 to 1.05), 0.68 (0.53 to 0.89), and 0.62 (0.45 to 0.84), respectively, in a model adjusting for age, sex, energy intake, field center, body mass index, dietary linolenic acid, saturated and monounsaturated fat, sodium intake, potassium, caffeine, fiber, and fruits and vegetables (P for trend = 0.002). This association was independent of calcium intake and was mainly observed among subjects consuming fewer calories from saturated fat (P for interaction = 0.014). Dairy consumption was inversely associated with systolic (P for trend = 0.003) but not diastolic (P for trend = 0.09) blood pressure. Although subjects consuming > or = 2 servings per day of dairy products and higher total linolenic acid had the lowest prevalence odds of HTN, there was no evidence for interaction between linolenic acid and dairy consumption on HTN (P for interaction = 0.65). In conclusion, our data indicate an inverse association between dairy consumption and prevalent HTN that was independent of dietary calcium, mainly among individuals consuming less saturated fat. This suggests that consumption of low-fat dairy products might be more beneficial for preventing HTN.

A genome scan for loci influencing anti-atherogenic serum bilirubin levels.

Epidemiological studies have shown an association of decreased serum bilirubin levels with coronary artery disease. Two segregation analyses in large pedigrees have suggested a major gene responsible for high bilirubin levels occurring in about 12% of the population. Based on a recessive model from a previous segregation analysis, we performed a genome scan using 587 markers genotyped in 862 individuals from 48 Utah pedigrees to detect loci linked to high bilirubin levels. As a complementary approach, non-parametric linkage (NPL) analysis was performed. These two methods identified four regions showing evidence for linkage. The first region is on chromosome 2q34-37 with multipoint LOD and NPL scores of 3.01 and 3.22, respectively, for marker D2S1363. This region contains a previously described gene, uridine diphosphate glycosyltransferase 1, which has been associated with high bilirubin levels. A polymorphism in the promoter of this gene was recently shown to be responsible for Gilbert syndrome which is associated with mild hyperbilirubinemia. The other regions were found on chromosomes 9q21, 10q25-26, and 18q12 with maximum NPL scores of 2.39, 1.55, and 2.79, respectively. Furthermore, we investigated in these pedigrees the association between bilirubin levels and coronary artery disease. One-hundred and sixty-one male and 41 female subjects had already suffered a coronary artery disease event. Male patients showed significantly lower bilirubin concentrations than age-matched controls. This association, however, was not observed in females. These results provide evidence that loci influencing bilirubin variation exist on chromosomes 2q34-37, 9q21, 10q25-26, and 18q12 and confirms the association of low bilirubin levels with coronary artery disease in males.