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Background: Premature coronary heart disease (CHD) is a major cause of death in women. We aimed to characterize biomarker profiles of women who developed CHD before and after age 65 years., Methods: In the Women's Health Study (median follow-up 21.5 years), women were grouped by age and timing of incident CHD: baseline age <65 years with premature CHD by age 65 years (25 042 women; 447 events) and baseline age ≥65 years with nonpremature CHD (2982 women; 351 events). Associations of 44 baseline plasma biomarkers measured using standard assays and a nuclear magnetic resonance (NMR)-metabolomics assay were analyzed using Cox models adjusted for clinical risk factors., Results: Twelve biomarkers showed associations only with premature CHD and included lipoprotein(a), which was associated with premature CHD [adjusted hazard ratio (HR) per SD: 1.29 (95% CI 1.17-1.42)] but not with nonpremature CHD [1.09(0.98-1.22)](Pinteraction = 0.02). NMR-measured lipoprotein insulin resistance was associated with the highest risk of premature CHD [1.92 (1.52-2.42)] but was not associated with nonpremature CHD (Pinteraction <0.001). Eleven biomarkers showed stronger associations with premature vs nonpremature CHD, including apolipoprotein B. Nine NMR biomarkers showed no association with premature or nonpremature CHD, whereas 12 biomarkers showed similar significant associations with premature and nonpremature CHD, respectively, including low-density lipoprotein (LDL) cholesterol [1.30(1.20-1.45) and 1.22(1.10-1.35)] and C-reactive protein [1.34(1.19-1.50) and 1.25(1.08-1.44)]., Conclusions: In women, a profile of 12 biomarkers was selectively associated with premature CHD, driven by lipoprotein(a) and insulin-resistant atherogenic dyslipoproteinemia. This has implications for the development of biomarker panels to screen for premature CHD., (© Association for Diagnostics & Laboratory Medicine 2024. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Background: We examined the interplay of apolipoprotein B (apoB) and LDL particle size, approximated by the LDL-cholesterol (LDL-C)/apoB ratio, on the risk of new-onset coronary heart disease (CHD)., Methods: Participants without cardiovascular disease from the UK Biobank (UKB; n = 308 182), the Women's Health Study (WHS; n = 26 204), and the Framingham Heart Study (FHS; n = 2839) were included. Multivariable Cox models were used to assess the relationship between apoB and LDL-C/apoB ratio and incidence of CHD (14 994 events). Our analyses were adjusted for age, sex (except WHS), HDL-cholesterol (HDL-C), systolic blood pressure, antihypertensive treatment, diabetes, and smoking., Results: In all 3 studies, there was a strong positive correlation between apoB and LDL-C (correlation coefficients r = 0.80 or higher) and a weak inverse correlation of apoB with LDL-C/apoB ratio (-0.28 ≤ r ≤ -0.14). For all 3 cohorts, CHD risk was higher for higher levels of apoB. Upon multivariable adjustment, the association between apoB and new-onset CHD remained robust and statistically significant in all 3 cohorts with hazard ratios per 1 SD (95% CI): 1.24 (1.22-1.27), 1.33 (1.20-1.47), and 1.24 (1.09-1.42) for UKB, WHS, and FHS, respectively. However, the association between LDL-C/apoB and CHD was statistically significant only in the FHS cohort: 0.78 (0.64-0.94)., Conclusions: Our analysis confirms that apoB is a strong risk factor for CHD. However, given the null association in 2 of the 3 studies, we cannot confirm that cholesterol-depleted LDL particles are substantially more atherogenic than cholesterol-replete particles. These results lend further support to routine measurement of apoB in clinical care., (© American Association for Clinical Chemistry 2022. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Previous results from Scandinavian cohorts have shown that obesity accentuates the effects of common genetic susceptibility variants on increased triglycerides (TG). Whether such interactions are present in the US population and further selective for particular TG-rich lipoprotein subfractions is unknown., Methods: We examined these questions using body mass index (BMI) and waist circumference (WC) among women of European ancestry from the Women's Genome Health Study (WGHS) (n = 21840 for BMI; n = 19313 for WC). A weighted genetic risk score (TG-wGRS) based on 40 published TG-associated single-nucleotide polymorphisms was calculated using published effect estimates., Results: Comparing overweight (BMI ≥ 25 kg/m 2 ) and normal weight (BMI < 25 kg/m 2 ) WGHS women, each unit increase of TG-wGRS was associated with TG increases of 1.013% and 1.011%, respectively, and this differential association was significant ( P interaction = 0.014). Metaanalyses combining results for WGHS BMI with the 4 Scandinavian cohorts (INTER99, HEALTH2006, GLACIER, MDC) (total n = 40026) yielded a more significant interaction ( P interaction = 0.001). Similarly, we observed differential association of the TG-wGRS with TG ( P interaction = 0.006) in strata of WC (<80 cm vs ≥80 cm). Metaanalysis with 2 additional cohorts reporting WC (INTER99 and HEALTH2006) (total n = 27834) was significant with consistent effects ( P interaction = 0.006). We also observed highly significant interactions of the TG-wGRS across the strata of BMI with very large, medium, and small TG-rich lipoprotein subfractions measured by nuclear magnetic resonance spectroscopy (all P interactions < 0.0001). The differential effects were strongest for very large TG-rich lipoprotein., Conclusions: Our results support the original findings and suggest that obese individuals may be more susceptible to aggregated genetic risk associated with common TG-raising alleles, with effects accentuated in the large TG-rich lipoprotein subfraction., (© 2017 American Association for Clinical Chemistry.)

Background: It is uncertain whether measurement of circulating total atherogenic lipoprotein particle cholesterol mass [non-HDL cholesterol (nonHDLc)] or particle concentration [apolipoprotein B (apo B) and LDL particle concentration (LDLp)] more accurately reflects risk of incident coronary heart disease (CHD). We evaluated CHD risk among women in whom these markers where discordant., Methods: Among 27533 initially healthy women in the Women's Health Study (NCT00000479), using residuals from linear regression models, we compared risk among women with higher or lower observed particle concentration relative to nonHDLc (highest and lowest residual quartiles, respectively) to individuals with agreement between markers (middle quartiles) using Cox proportional hazards models., Results: Although all 3 biomarkers were correlated ( r ≥ 0.77), discordance occurred in up to 20.2% of women. Women with discordant high particle concentration were more likely to have metabolic syndrome (MetS) and diabetes (both P < 0.001). Over a median follow-up of 20.4 years, 1246 CHD events occurred (514725 person-years). Women with high particle concentration relative to nonHDLc had increased CHD risk: age-adjusted hazard ratio (95% CI) = 1.77 (1.56-2.00) for apo B and 1.70 (1.50-1.92) for LDLp. After adjustment for clinical risk factors including MetS, these risks attenuated to 1.22 (1.07-1.39) for apo B and 1.13 (0.99-1.29) for LDLp. Discordant low apo B or LDLp relative to nonHDLc was not associated with lower risk., Conclusions: Discordance between atherogenic particle cholesterol mass and particle concentration occurs in a sizeable proportion of apparently healthy women and should be suspected clinically among women with cardiometabolic traits. In such women, direct measurement of lipoprotein particle concentration might better inform CHD risk assessment., (© 2016 American Association for Clinical Chemistry.)

Background: Nonfasting triglycerides are similar or superior to fasting triglycerides at predicting cardiovascular events. However, diagnostic cutpoints are based on fasting triglycerides. We examined the optimal cutpoint for increased nonfasting triglycerides., Methods: We obtained baseline nonfasting (<8 h since last meal) samples from 6391 participants in the Women's Health Study who were followed prospectively for ≤17 years. The optimal diagnostic threshold for nonfasting triglycerides, determined by logistic regression models by use of c-statistics and the Youden index (sum of sensitivity and specificity minus 1), was used to calculate hazard ratios (HRs) for incident cardiovascular events. Performance was compared to thresholds recommended by the American Heart Association (AHA) and European guidelines., Results: The optimal threshold was 175 mg/dL (1.98 mmol/L), with a c-statistic of 0.656, statistically better than the AHA cutpoint of 200 mg/dL (c-statistic 0.628). For nonfasting triglycerides above and below 175 mg/dL, after adjusting for age, hypertension, smoking, hormone use, and menopausal status, the HR for cardiovascular events was 1.88 (95% CI 1.52-2.33, P < 0.001), and for triglycerides measured at 0-4 and 4-8 h since the last meal, 2.05 (1.54- 2.74) and 1.68 (1.21-2.32), respectively. We validated performance of this optimal cutpoint by use of 10-fold cross-validation and bootstrapping of multivariable models that included standard risk factors plus total and HDL cholesterol, diabetes, body mass index, and C-reactive protein., Conclusions: In this study of middle-aged and older apparently healthy women, we identified a diagnostic threshold for nonfasting hypertriglyceridemia of 175 mg/dL (1.98 mmol/L), with the potential to more accurately identify cases than the currently recommended AHA cutpoint., (© 2015 American Association for Clinical Chemistry.)

Background: Animal data suggest that natriuretic peptides play an important role in energy metabolism, but prospective studies evaluating a relationship between these peptides and type 2 diabetes mellitus (T2DM) in humans are few and results are conflicting., Methods: We used a prospective case-cohort approach (n = 491 T2DM cases, n = 561 reference subcohort) within the Women's Health Study to evaluate baseline N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentrations and the risk of incident T2DM. We also tested for associations between 4 common variants in the natriuretic peptide A and B genes (NPPA and NPPB) and NT-proBNP concentrations (n = 458) and incident T2DM (n = 1372 cases among 22 607 women)., Results: Case subjects had higher median baseline body mass index (29.4 vs 25.0 kg/m(2), P < 0.001) and lower baseline median (interquartile range) NT-proBNP concentrations [46.8 ng/L (26.1-83.2) vs 66.7 ng/L (39.3-124.7), P < 0.001]. In proportional hazards models adjusting for established diabetes risk factors, women in the highest quartile of baseline NT-proBNP concentration (≥ 117.4 ng/L) had a 49% reduction in risk of T2DM [hazard ratio (HR) 0.51, 0.30-0.86, P = 0.01] relative to those in the lowest quartile. Two of the 4 tested variants in NPPA and NPPB (rs632793, rs198389) were associated with increased NT-proBNP concentrations and reduced risk of T2DM. For example, each copy of the minor allele of rs632793 was associated with increased NT-proBNP [β (SE) = 0.201 (0.063), P < 0.01] and decreased T2DM risk (HR 0.91, 0.84-0.989, P = 0.026)., Conclusions: NT-proBNP concentrations that are high, but still within the reference interval, associate with reduced risk of incident diabetes in women and support a favorable role for natriuretic peptides in the prevention of T2DM.

Background: Adiponectin may have a protective role in the development of obesity-related metabolic and vascular disorders, including hypertension. We conducted a prospective, nested case control study to investigate the relation between baseline plasma adiponectin, measures of adiposity, and subsequent risk of hypertension., Methods: We selected 400 white and 400 black postmenopausal women, age <70 years, who developed incident hypertension during 5.9-year follow-up and an equal number of age- and race-matched controls in the Women's Health Initiative Observational Study. We measured plasma concentrations of total adiponectin in their baseline blood samples., Results: In crude matched models, plasma adiponectin was inversely associated with risk of hypertension among both white and black women. The association appeared to be nonlinear in white women but dose related in black women. Adjustment for lifestyle factors, measures of obesity, and obesity-related clinical factors attenuated these associations. The multivariable relative risk (95% CI) of hypertension across increasing quartiles of plasma adiponectin were 1.00, 0.98 (0.66-1.46), 0.63 (0.41-0.97), and 0.92 (0.60-1.42) in white women (P(trend): 0.38) and 1.00, 0.96 (0.64-1.46), 0.83 (0.53-1.29), and 0.58 (0.36-0.94) in black women (P(trend): 0.02). Further adjustment for inflammatory markers and endothelial markers eliminated the association in white, but not black, women., Conclusions: In this prospective, nested case control study, we found an inverse association between plasma adiponectin and risk of hypertension in white and black postmenopausal women. The reduced risk of hypertension was limited to only intermediate concentrations of adiponectin in white women whereas it was graded across quartiles of adiponectin in black women., (© 2012 American Association for Clinical Chemistry)

Background: Findings regarding the association of lipoprotein-associated phospholipase A₂ (Lp-PLA2) activity and mass with incident cardiovascular disease (CVD) have been inconsistent, and their role in risk prediction is uncertain., Methods: A case-cohort sample from the Women's Health Initiative Observational Study (WHI-OS) comprised 1821 CVD cases and a reference subcohort of 1992 women. We used Cox regression models with inverse sampling weights to assess the association of Lp-PLA2 mass and activity with CVD (myocardial infarction, stroke, and CVD mortality)., Results: Subcohort means were 184.3 mmol/min/mL for Lp-PLA2 activity and 499.2 μg/L for Lp-PLA2 mass, with 99% having mass above 200 μg/L, the clinically recommended cut point. Both activity and mass were positively associated with incident CVD in age- and race/ethnicity-adjusted analyses. Following adjustment according to CVD risk factors, the association with activity became null (hazard ratio = 1.02 for top vs bottom quartile, 95% CI = 0.79-1.33, P for trend = 0.65), but the association with mass remained (hazard ratio = 1.84, 95% CI = 1.45-2.34, P for trend < 0.0001). In contrast to blood pressure, HDL, and hsCRP, reclassification statistics for Lp-PLA2 mass did not suggest improvement for overall CVD after full adjustment., Conclusions: In the WHI-OS Lp-PLA2 mass, but not activity, was independently associated with CVD. However, model fit did not significantly improve with Lp-PLA2 mass, and assay calibration remains a clinical concern.

Background: Although lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) levels are associated with cardiovascular events, Lp-PLA(2) is physically linked to LDL cholesterol (LDL-C). Whether measures of Lp-PLA(2) mass or activity continue to predict risk after LDL-C reduction by statin therapy is uncertain., Methods: Lp-PLA(2) mass concentration and activity were evaluated at baseline and after treatment in the Justification for the Use of Statins in Prevention: an Intervention Trial Evaluating Rosuvastatin (JUPITER) trial comparing rosuvastatin 20 mg to placebo among 17 802 men and women without cardiovascular disease or diabetes at study entry. The relationships of Lp-PLA(2) mass and activity with risk of future vascular events were evaluated in the placebo and rosuvastatin groups., Results: Before randomization, levels of Lp-PLA(2) mass and activity correlated moderately with each other and with LDL-C. The magnitude of these correlations increased after statin therapy. Rosuvastatin reduced Lp-PLA(2) mass by 33.8%, Lp-PLA(2) activity by 33.2%, and LDL-C by 48.7% (all P < 0.0001). Among those study participants allocated to placebo, increasing quartiles of Lp-PLA(2) activity (P(trend) = 0.04) but not Lp-PLA(2) mass (P(trend) = 0.92) were associated with incident cardiovascular events after adjustment for LDL-C and conventional risk factors. Comparable analyses conducted among those allocated to rosuvastatin revealed no significant relationship between Lp-PLA(2) levels and subsequent vascular events. The ability of rosuvastatin to reduce vascular events was not significantly modified by baseline Lp-PLA(2) level., Conclusions: Among JUPITER trial participants allocated to placebo, levels of Lp-PLA(2) activity, but not mass, were associated with cardiovascular risk. However, Lp-PLA(2) no longer predicted risk or modified clinical outcomes when participants were treated with rosuvastatin.

Background: Although statin therapy is known to increase concentrations of PCSK9, whether this effect is related to the magnitude of LDL reduction is uncertain. This study was undertaken to understand the extent of this effect and examine the relationship between PCSK9 and LDL cholesterol (LDL-C) reduction., Methods: We measured plasma PCSK9 concentrations by ELISA at baseline and at 1 year in 500 men and 500 women participating in the Justification for Use of Statins in Prevention: an Intervention Trial Evaluating Rosuvastatin (JUPITER) trial that randomly allocated participants to rosuvastatin 20 mg daily or placebo. We also evaluated rs11591147, a single nucleotide polymorphism known to have an impact on plasma PCSK9 concentrations., Results: At baseline, median (interquartile range) PCSK9 concentrations were higher in women [73 (62-90)] ng/mL than in men [69 (57-81) ng/mL] (P<0.005). During 1 year, there was no change in PCSK9 concentrations in the placebo arm, suggesting stability in time. In contrast, the rosuvastatin increased PCSK9 by 35% in women [101 (82-117) ng/mL] and 28% in men [89 (71-109) ng/mL] (P<0.0001). Among those allocated to rosuvastatin, greater reductions in LDL-C were associated with greater increases in PCSK9 on both absolute and relative scales (r=-0.15, P<0.0005). Furthermore PCSK9 (rs11591147) did not alter the magnitude of LDL-C reduction associated with rosuvastatin use., Conclusions: In this randomized trial, rosuvastatin increased plasma concentration of PCSK9 in proportion to the magnitude of LDL-C reduction; the LDL-C response to statin could not be inferred by PCSK9 concentrations.

Background: Systemic inflammation and endothelial activation are implicated in the development of hypertension. However, epidemiologic studies have yet to compare multiple corresponding biomarkers in relation to risk of hypertension, particularly in multiethnic populations., Methods: We identified 800 individuals with incident hypertension and 800 matched controls, each group with equal numbers of white and black women, in a nested case-control study within the Women's Health Initiative Observational Study. We measured markers of inflammation [high-sensitivity C-reactive protein (hsCRP), interleukin (IL)-6, IL-1β, tumor necrosis factor receptor 2 (TNF-r2)] and endothelial activation [soluble intercellular adhesion molecule-1 (sICAM-1)] in baseline blood samples., Results: Before adjustment for measures of adiposity, higher hsCRP and IL-6 concentrations were associated with increased risk of hypertension in both white and black women, higher TNF-r2 was associated with increased risk of hypertension in black women only, and IL-1β and sICAM-1 were not associated with risk of hypertension. All the positive associations were attenuated after adjustment for body mass index. The resulting multivariable-adjusted relative risks (95% CI) of hypertension comparing the highest vs lowest quartile were 1.52 (0.94-2.48) and 1.23 (0.76-1.97) for hsCRP and IL-6 in white women and 1.30 (0.81-2.07), 1.58 (0.96-2.59), and 1.49 (0.94-2.36) for hsCRP, IL-6, and TNF-r2 in black women. The results after adjustment for waist circumference were similar., Conclusions: After adjustment for measures of adiposity, there was no significant association of hsCRP, IL-6, IL-1β, TNF-r2, or sICAM-1 with incident hypertension in either white or black women. The interrelationships between inflammation and adiposity in development of hypertension need further investigation.

Background: Previous studies have demonstrated that cardiovascular risk is higher with increased lipoprotein(a) [Lp(a)]. Whether Lp(a) concentration is related to type 2 diabetes is unclear., Methods: In 26 746 healthy US women (mean age 54.6 years), we prospectively examined baseline Lp(a) concentrations and incident type 2 diabetes (n = 1670) for a follow-up period of 13 years. We confirmed our findings in 9652 Danish men and women with prevalent diabetes (n = 419). Analyses were adjusted for risk factors that included age, race, smoking, hormone use, family history, blood pressure, body mass index, hemoglobin A(1c) (Hb A(1c)), C-reactive protein, and lipids., Results: Lp(a) was inversely associated with incident diabetes, with fully adjusted hazard ratios (HRs) and 95% CIs for quintiles 2-5 vs quintile 1 of 0.87 (0.75-1.01), 0.80 (0.68-0.93), 0.88 (0.76-1.02), and 0.78 (0.67-0.91); P for trend 0.002. The association was stronger in nonfasting women, for whom respective HRs were 0.79 (0.58-1.09), 0.78 (0.57-1.08), 0.66 (0.46-0.93), and 0.56 (0.40-0.80); P for trend 0.001; P for interaction with fasting status 0.002. When we used Lp(a) > or =10 mg/L and Hb A(1c) <5% as reference values, the adjusted HRs were 1.62 (0.91-2.89) for Lp(a) <10 mg/L and Hb A(1c) <5%, 3.50 (3.06-4.01) for Lp(a) > or =10 mg/L and Hb A(1c) 5%-<6.5%, and 5.36 (4.00-7.19) for Lp(a) <10 mg/L and Hb A(1c) 5%-<6.5%. Results were similar in nonfasting Danish men and women, for whom adjusted odds ratios were 0.75 (0.55-1.03), 0.64 (0.46-0.88), 0.74 (0.54-1.01), and 0.58 (0.42-0.79) for Lp(a) quintiles 2-5 vs quintile 1; P for trend 0.002., Conclusions: Our results indicated that Lp(a) was associated inversely with risk of type 2 diabetes independently of risk factors, in contrast to prior findings of positive associations of Lp(a) with cardiovascular risk.

Background: National Cholesterol Education Program (NCEP) guidelines recommend development of direct assays for LDL cholesterol (LDL-C) measurement, but it is unclear how these assays compare with Friedewald calculation in predicting cardiovascular disease (CVD)., Methods: In a study of 27 331 healthy women with triglycerides

Background: The JUPITER (Justification for the Use of Statins in Prevention: An Intervention Trial Evaluating Rosuvastatin) trial suggests that increased high-sensitivity C-reactive protein (hsCRP) concentrations may be useful in decisions about the initiation of statin therapy for primary prevention of vascular disease. Although studies of specific populations have suggested that hsCRP is a reliable longitudinal marker, it is unclear how strongly hsCRP tracks in individuals after a single increased concentration., Methods: We evaluated tracking of hsCRP in 8901 individuals randomized to placebo in the JUPITER trial. These individuals had screening LDL cholesterol concentrations <130 mg/dL (<3.37 mmol/L) and hsCRP concentrations > or =2 mg/L, with subsequent hsCRP measurements made before randomization; at 13 weeks; 1, 2, 3, and 4 years later; and at trial termination. Longitudinal trends and associations were evaluated nonparametrically with box plots and Spearman correlations. After data transformation to achieve normality, repeated-measures regression models estimated the intraclass correlation of hsCRP, with and without controlling for known demographic, lifestyle, and medical determinants of hsCRP concentration. For comparison, we evaluated tracking of systolic and diastolic blood pressure; total, LDL, and HDL cholesterol; and fasting triglycerides., Results: The median hsCRP concentration in these untreated individuals showed modest regression to the mean over time, declining from 3.8 mg/L at randomization to 3.4 mg/L at 4 years. Tracking correlations for hsCRP over time were comparable to those for blood pressure and LDL cholesterol, but lower than those for HDL, fasting triglycerides, and total cholesterol. The intraclass correlation for repeated hsCRP measurements was 0.54 (95% CI, 0.53-0.55) without covariate adjustment and 0.50 (95% CI, 0.49-0.51) after adjustment for demographic, lifestyle, and comorbidity determinants., Conclusions: Concentrations of hsCRP show strong tracking, even after selection of individuals with initially high values. Without statin therapy, increased concentrations of hsCRP generally remain high over time.

Background: Recent technologies enable genetic association studies of common clinical analytes on a genomewide basis in populations numbering thousands of individuals. The first publications using these technologies are already revealing novel biological functions for both genic and nongenic loci, and are promising to transform knowledge about the biological networks underlying disease pathophysiology. These early studies have also led to development of a set of principles for conducting a successful genomewide association study (GWAS)., Content: This review focuses on these principles with emphasis on the use of GWAS for plasma-based analytes to better understand human disease, with examples from cardiovascular biology., Conclusions: The correlation of common genetic variation on a genomewide basis with clinical analytes, or any other outcome of interest, promises to reveal how parts of the genome work together in human physiology. Nonetheless, performing a genomewide association study demands an awareness of very specific epidemiologic and analytic principles.

Background: Recent data have implicated tumor necrosis factor (ligand) superfamily, member 4 (TNFSF4) gene variation in myocardial infarction in women; however, no prospective data are available on either incident arterial or venous disorders., Methods: We evaluated 2 previously characterized TNFSF4 gene variants (-921C>T and dbSNP rs3850641) with a) incident arterial events using a prospective case-cohort design with 344 incident CVD cases and 2254 control participants, all white, drawn from the Women's Health Study cohort with 10 years of follow-up, and b) venous thromboembolism (VTE) risk using a nested, matched case-control design of 108 white male pairs (drawn from the Physicians' Health Study cohort) and a case-cohort design of white female participants consisting of 125 cases and 2269 controls (drawn from the Women's Health Study cohort), analyzed separately., Results: Genotype distributions were in Hardy-Weinberg equilibrium. Results from a marker-by-marker regression analysis, adjusting for traditional risk factors, showed a significant association of -921C>T with an increased risk of VTE in women (additive: odds ratio 1.86; 95% CI 1.17-2.92, P = 0.008) in women. Furthermore, using a haplotype-based regression analysis, haplotype C-G was associated with a reduced risk of VTE relative to the referent haplotype, C-A (odds ratio 0.50; 95% CI 0.27-0.92; P = 0.02). In contrast, we found little evidence for an association of the variants/haplotypes with risk of VTE in men or CVD risk in women (as previously reported)., Conclusions: Our present findings, if corroborated in other prospective investigations, suggest that the TNFSF4 variants tested may be useful indicators for assessing the risk of venous thromboembolism.

The primary aim of the Women's Genome Health Study (WGHS) is to create a comprehensive, fully searchable genome-wide database of >360 000 single nucleotide polymorphisms among at least 25 000 initially healthy American women participating in the ongoing NIH-funded Women's Health Study (WHS). These women have already been followed over a 12-year period for major incident health events including but not limited to myocardial infarction, stroke, cancer, diabetes, osteoporosis, venous-thromboembolism, cognitive decline, and common visual disorders such as age- related macular degeneration and cataracts. Investigations within the WGHS will seek to identify relevant patterns of genetic polymorphism that predict future disease states in otherwise healthy American women, and to evaluate patterns of genetic polymorphism that relate to multiple intermediate phenotypes including blood-based determinants of disease that were measured at baseline for each study participant. By linking genome-wide data to the existing epidemiologic databank of the parent WHS, which includes comprehensive dietary, behavioral, and traditional exposure data on each participant since cohort inception in 1992, the WGHS will also allow exploration of gene-environment and gene-gene interactions as they relate to incident disease states. Thus, with continued follow-up of the WHS, the WGHS provides a unique scientific resource-a full-cohort, prospective, genome-wide association study among initially healthy American women.

Background: Heat shock protein 27 (HSP27) has been hypothesized to be a potential biomarker of atherothrombosis. However, no prospective studies have yet been performed to investigate the association between HSP27 plasma concentration and incident cardiovascular events among initially healthy individuals., Methods: We evaluated plasma concentrations of HSP27 at baseline among 255 initially healthy participants in the Women's Health Study who subsequently developed myocardial infarction, ischemic stroke, or cardiovascular death during a follow-up period of up to 5.9 years and among an equal number of women matched for age and smoking but who remained free of cardiovascular disease over the same time period., Results: Overall, HSP27 plasma concentrations were inversely associated with age (Spearman correlation coefficient r = -0.258, P <0.001), but not with other established cardiovascular risk factors. Conditional logistic regression analysis showed no significant association of baseline HSP27 plasma concentration with future cardiovascular disease; the odds ratio for upper vs lower tertile of HSP27 concentration at baseline was 0.99 (95% CI 0.62-1.57, P for trend = 0.99)., Conclusion: In this prospective study of initially healthy women, baseline HSP27 plasma concentration was not associated with incident cardiovascular events.

Background: Cohort studies suggest an association between variation in the estrogen receptor-alpha gene (ESR1) and cardiovascular disease (CVD), but data are lacking for the effect of variation in the estrogen receptor-beta gene (ESR2)., Methods: Three polymorphisms of the ESR2 gene, and their associated haplotypes, were evaluated in 296 white women from the Women's Health Study and 566 white men from the Physicians' Health Study who developed CVD [myocardial infarction (MI) or ischemic stroke], each matched 1:1 to a member of the cohort study who remained free from CVD. Blood samples and cardiovascular risk information were collected at baseline., Results: Women, but not men, who developed CVD or MI, but not ischemic stroke, were more likely to have the rs1271572 polymorphism variant T allele (P = 0.05 and 0.02) and less likely to have the rs1256049 polymorphism variant A allele (P = 0.003 and 0.004). No associations were observed for rs4986938. In conditional logistic multivariate regression, the rs1271572 variant was associated with increased odds of CVD [odds ratio (OR) = 1.49, 95% CI: 1.10-2.01] and MI (OR = 1.46, 95% CI: 0.96-2.23), whereas the rs1256049 variant was associated with decreased odds of CVD (OR = 0.37, 95% CI: 0.17-0.79) and MI (OR = 0.25, 95% CI: 0.09-0.73) in women. A common haplotype that included the rs1271572 variant was associated with a 7-fold increased risk of MI in women., Conclusions: Two tightly linked polymorphisms of ESR2 were associated with risk of CVD, particularly MI, in women but not men. Additional studies of ESR2 genetic variation and risk of CVD are warranted.

Background: Hyperhomocysteinemia has been associated with a higher risk of cardiovascular disease (CVD) in epidemiological studies, but recent trials have failed to show a benefit of lowering homocysteine. To address this apparent paradox, we explored whether interaction between genetic and dietary factors related to homocysteine metabolism contributes to CVD risk., Methods: We evaluated the associations of homocysteine, methylenetetrahydrofolate reductase (MTHFR) 677C>T genotype, and dietary intake of folate/B-vitamins with subsequent CVD events in 24 968 apparently healthy white American women followed for 10 years. Plasma homocysteine was measured using an enzymatic assay. MTHFR genotype was determined with a multiplex PCR using biotinylated primers., Results: In unadjusted analyses, homocysteine showed moderately strong linear associations with CVD, with hazard ratios (95% CI) comparing top with bottom quintiles for total CVD of 1.92 (1.55-2.37), myocardial infarction 2.32 (1.52-3.54), and ischemic stroke 2.25 (1.45-3.50), all P(trend) <0.001. These ratios were markedly attenuated after adjusting for traditional risk factors and socioeconomic status to 1.08 (0.86-1.36), P(trend) = 0.12; 1.20 (0.76-1.87), P(trend) = 0.14; and 1.21 (0.75-1.94), P(trend) = 0.50, respectively. Homocysteine was associated with MTHFR genotype (1.4 micromol/L higher homocysteine for TT vs CC, P <0.001) and inversely with intake of folate, vitamin B(2), B(6), and B(12), all P(trend) <0.001. However, there was no association of MTHFR genotype or dietary folate/B-vitamins with CVD. In addition, there were no gene-diet or gene-homocysteine interactions in relation to CVD., Conclusions: In this large-scale prospective study, the association of homocysteine with CVD was markedly attenuated after adjusting for risk factors and was not modified by MTHFR 677C>T or intake of folate or B-vitamins.

Background: Adiponectin (ADIPOQ) gene variations are associated with risk of cardiovascular disease in patients with diabetes. No prospective data are available, however, on the risk of atherothrombotic disorders in persons with ADIPOQ variations who do not have diabetes., Methods: From a group of DNA samples collected at baseline in a prospective cohort of 14 916 initially healthy American men, we assessed the presence of 5 ADIPOQ genetic variants (rs266729, rs182052, rs822396, rs2241766, and rs1501299) in samples from 600 Caucasian men who subsequently suffered an atherothrombotic event (incident myocardial infarction or ischemic stroke) and from 600 age- and smoking-matched Caucasian men who remained free of reported vascular disease during follow-up (controls)., Results: Genotype distributions for the variations tested were in Hardy-Weinberg equilibrium. Marker-by-marker conditional logistic regression analysis, adjusted for potential risk factors, showed an association of rs266729 [recessive: odds ratio (OR), 0.26; 95% confidence interval (CI), 0.10-0.64; P=0.004] and rs182052 (recessive: OR, 0.40; 95% CI, 0.21-0.76; P=0.006) with decreased risk of ischemic stroke. These findings remained significant after Bonferroni correction. Haplotype-based (constituted by rs266729, rs182052, and rs822396) conditional logistic regression analysis, adjusted for the same potential risk factors, showed an association of haplotype G-A-G (OR, 0.28; 95% CI, 0.09-0.87; P=0.03) with decreased risk of ischemic stroke. Prespecified analysis limited to participants without baseline diabetes showed similar significant findings., Conclusions: The present prospective investigation provides further evidence for a protective role of adiponectin gene variation in the risk of ischemic stroke that was independent of the presence of diabetes.

Background: The relationship of lipoprotein (a) [Lp(a)] concentrations with risk of coronary heart disease needs clarification, especially for threshold values for increased risk and for possible interactions with LDL-cholesterol concentrations and apolipoprotein (a) [apo(a)] size polymorphism. This study was designed to examine the ability of baseline Lp(a) concentration and apo(a) size to predict future severe angina pectoris in apparently healthy men., Methods: Baseline Lp(a) concentration and apo(a) size were determined in 195 men who subsequently developed angina and in 195 men who remained free of cardiovascular disease for 5 years., Results: Cases had higher median Lp(a) concentrations than did controls (30.6 vs 22.5 nmol/L; P = 0.02). Lp(a) concentration was predictive of angina [relative risk (RR) from lowest to highest quintiles: 1.0, 1.5, 1.0, 1.8, and 2.6; P for trend = 0.015]. The increased risk was approximately 4-fold (95% confidence interval, 1.4- to 11-fold) among men who had Lp(a) above the 95th percentile (>158 nmol/L). Men with Lp(a) concentrations in the highest quintile and LDL-cholesterol concentrations >1600 mg/L had a 12-fold increased risk (95% confidence interval, 1.5- to 43-fold). Small apo(a) size isoforms also significantly predicted risk of angina (RR for lowest quintile = 4.1; P for trend = 0.004). When the independent effect of Lp(a) concentration and apo(a) size was assessed by including them in the same multivariate model, only the association between apo(a) size and risk remained significant., Conclusions: High Lp(a) predicts risk of angina, and the risk is substantially increased with high concomitant LDL-cholesterol. Small apo(a) size predicts angina with greater strength and independence than Lp(a) concentration.

Background: The distribution of C-reactive protein (CRP) concentrations among children and young adults in the US is not known at present., Methods: We used data from 3348 US children and young adults 3-19 years of age who participated in the National Health and Nutrition Examination Survey, 1999-2000, to describe the distribution of CRP concentrations, based on results obtained with a high-sensitivity latex-enhanced turbidimetric assay., Results: The range of CRP concentrations was 0.1-90.8 mg/L (mean, 1.6 mg/L; geometric mean, 0.5 mg/L; median, 0.4 mg/L). CRP concentrations increased with age. Females 16-19 years of age had higher concentrations than males in this age range (P = 0.003). Mexican Americans had the highest CRP concentrations among the three major race or ethnic groups (P <0.001)., Conclusions: For the first time, these data describe the CRP concentration distribution among US children and young adults, based on results obtained with a high-sensitivity assay.

Background: Coronary heart disease remains the leading cause of morbidity and mortality in the industrialized world. Clinical and laboratory studies have shown that inflammation plays a major role in the initiation, progression, and destabilization of atheromas. C-Reactive protein (CRP), an acute phase reactant that reflects low-grade systemic inflammation, has been studied in a variety of cardiovascular diseases., Approach: Findings from prospective clinical trials were examined to determine the prognostic utility of CRP in acute coronary syndromes, and observations from epidemiological studies were reviewed to determine the ability of CRP to predict future first coronary events. The analytical considerations of CRP measurement in these clinical applications were also examined., Content: In patients with established coronary disease, CRP has been shown to predict adverse clinical events. In addition, prospective studies have consistently shown that CRP is a strong predictor of future coronary events in apparently healthy men and women. The relative risk associated with CRP is independent of other cardiovascular disease risk factors. High-sensitivity CRP (hs-CRP) assays are needed for risk assessment of cardiovascular disease. Such assays are currently available but may require further standardization because patients' results will be interpreted using population-based cutpoints. Preventive therapies to attenuate coronary risk in individuals with increased hs-CRP concentrations include aspirin and statin-type drugs., Summary: hs-CRP has prognostic utility in patients with acute coronary syndromes and is a strong independent predictor of future coronary events in apparently healthy subjects.

Background: Increased concentrations of high-sensitivity C-reactive protein (hs-CRP), a marker of systemic inflammation, are associated with increased risk for coronary heart disease. Because of its relationship to inflammation, hs-CRP has considerable biologic variation. This study was carried out to characterize CRP variation and to compare it to another risk factor, total serum cholesterol., Methods: One hundred thirteen individuals were scheduled to have five measurements each of hs-CRP and total cholesterol carried out at quarterly intervals over a 1-year period. Variations of hs-CRP and total cholesterol were characterized, and classification accuracy was described and compared for both., Results: The relative variation was comparable for hs-CRP and total cholesterol. When classified by quartile, 63% of first and second hs-CRP measurements were in agreement; for total cholesterol it was 60%. Ninety percent of hs-CRP measurements were within one quartile of each other. This relationship was not altered by the use of log-transformed hs-CRP data., Conclusion: hs-CRP has a degree of measurement stability that is similar to that of total cholesterol.

Background: The concentration of C-reactive protein (CRP) in otherwise healthy subjects has been shown to predict future risk of myocardial infarction and stroke. CRP is synthesized by the liver in response to interleukin-6, the serum concentration of which is subject to diurnal variation., Methods: To examine the existence of a time-of-day effect for baseline CRP values, we determined CRP concentrations in hourly blood samples drawn from healthy subjects (10 males, 3 females; age range, 21-35 years) during a baseline day in a controlled environment (8 h of nighttime sleep)., Results: Overall CRP concentrations were low, with only three subjects having CRP concentrations >2 mg/L. Comparison of raw data showed stability of CRP concentrations throughout the 24 h studied. When compared with cutoff values of CRP quintile derived from population-based studies, misclassification of greater than one quintile did not occur as a result of diurnal variation in any of the subjects studied. Nonparametric ANOVA comparing different time points showed no significant differences for both raw and z-transformed data. Analysis for rhythmic diurnal variation using a method fitting a cosine curve to the group data was negative., Conclusions: Our data show that baseline CRP concentrations are not subject to time-of-day variation and thus help to explain why CRP concentrations are a better predictor of vascular risk than interleukin-6. Determination of CRP for cardiovascular risk prediction may be performed without concern for diurnal variation.

Background: Prospective studies have shown that C-reactive protein (CRP) can be used to predict risk of future cardiovascular events. High-sensitivity methods for CRP (hs-CRP) measurement are needed for this purpose., Methods: We compared the clinical efficacy of an automated and commercially available latex-enhanced assay (Latex) for hs-CRP (Dade Behring) to a validated in-house ELISA, previously shown to predict future peripheral arterial disease (PAD) in asymptomatic populations. Using a prospective, nested, case-control design, we measured baseline hs-CRP concentrations in 144 apparently healthy men who subsequently developed symptomatic PAD and 144 age- and smoking habit-matched controls who remained free of vascular disease over the follow-up period of 60 months., Results: The two hs-CRP assays correlated highly (r = 0.95; P <0.001), and all but two participants were classified into concordant quartiles or varied by only one quartile. The median hs-CRP of the case group was significantly higher than that of controls when measured by either the ELISA (1.34 vs 0.99 mg/L; P = 0.034) or the Latex method (1.80 vs 1.20 mg/L; P = 0.042). Furthermore, for both ELISA and the Latex method, the calculated relative risks of developing PAD increased significantly with each increasing quartile of hs-CRP. The calculated interquartile increase in relative risk of PAD was 31% (95% confidence interval, 5.2-62.2%; P = 0.01) for ELISA and 34% (95% confidence interval, 8.2-66.1%; P = 0.007) for the Latex method., Conclusions: Our findings indicate that the Latex method is equally as efficacious as the validated ELISA in classifying patients into cutoff points established by prospective studies for risk stratification for coronary and cerebrovascular disease.