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Context: Plasma levels of C-reactive protein (CRP) are independently associated with risk of coronary heart disease, but whether CRP is causally associated with coronary heart disease or merely a marker of underlying atherosclerosis is uncertain., Objective: To investigate association of genetic loci with CRP levels and risk of coronary heart disease., Design, Setting, and Participants: We first carried out a genome-wide association (n = 17,967) and replication study (n = 13,615) to identify genetic loci associated with plasma CRP concentrations. Data collection took place between 1989 and 2008 and genotyping between 2003 and 2008. We carried out a mendelian randomization study of the most closely associated single-nucleotide polymorphism (SNP) in the CRP locus and published data on other CRP variants involving a total of 28,112 cases and 100,823 controls, to investigate the association of CRP variants with coronary heart disease. We compared our finding with that predicted from meta-analysis of observational studies of CRP levels and risk of coronary heart disease. For the other loci associated with CRP levels, we selected the most closely associated SNP for testing against coronary heart disease among 14,365 cases and 32,069 controls., Main Outcome Measure: Risk of coronary heart disease., Results: Polymorphisms in 5 genetic loci were strongly associated with CRP levels (% difference per minor allele): SNP rs6700896 in LEPR (-14.8%; 95% confidence interval [CI], -17.6% to -12.0%; P = 6.2 x 10(-22)), rs4537545 in IL6R (-11.5%; 95% CI, -14.4% to -8.5%; P = 1.3 x 10(-12)), rs7553007 in the CRP locus (-20.7%; 95% CI, -23.4% to -17.9%; P = 1.3 x 10(-38)), rs1183910 in HNF1A (-13.8%; 95% CI, -16.6% to -10.9%; P = 1.9 x 10(-18)), and rs4420638 in APOE-CI-CII (-21.8%; 95% CI, -25.3% to -18.1%; P = 8.1 x 10(-26)). Association of SNP rs7553007 in the CRP locus with coronary heart disease gave an odds ratio (OR) of 0.98 (95% CI, 0.94 to 1.01) per 20% lower CRP level. Our mendelian randomization study of variants in the CRP locus showed no association with coronary heart disease: OR, 1.00; 95% CI, 0.97 to 1.02; per 20% lower CRP level, compared with OR, 0.94; 95% CI, 0.94 to 0.95; predicted from meta-analysis of the observational studies of CRP levels and coronary heart disease (z score, -3.45; P < .001). SNPs rs6700896 in LEPR (OR, 1.06; 95% CI, 1.02 to 1.09; per minor allele), rs4537545 in IL6R (OR, 0.94; 95% CI, 0.91 to 0.97), and rs4420638 in the APOE-CI-CII cluster (OR, 1.16; 95% CI, 1.12 to 1.21) were all associated with risk of coronary heart disease., Conclusion: The lack of concordance between the effect on coronary heart disease risk of CRP genotypes and CRP levels argues against a causal association of CRP with coronary heart disease.

Background: High-sensitivity C-reactive protein (CRP) is an inflammatory marker that predicts coronary heart disease (CHD) and, in recent studies, incident heart failure (HF). Whether the association of inflammation with incident HF is explained by worse baseline left ventricular dysfunction or by underlying CHD is unknown., Methods and Results: Serum CRP was measured in a cohort of 985 outpatients with established CHD from the Heart and Soul Study. During 3 years of follow-up, 15% of the participants with elevated CRP levels (>3 mg/L) were hospitalised for HF, compared with 7% of those with CRP

Background: Elevated levels of C-reactive protein (CRP) are associated with an increased risk of coronary events, but whether inflammation is associated with inducible ischemia in patients with stable coronary disease is unknown., Methods and Results: We recruited patients with known coronary disease from 2 VA Medical Centers and 1 University-based medical center for the Heart and Soul Study. We measured CRP levels in 118 participants who had exercise-induced ischemia and in 111 who did not have inducible ischemia, as determined by stress echocardiography. We used logistic regression to examine the risk of exercise-induced ischemia associated with elevated CRP. We found that 75% (39/52) of participants in the highest CRP category (>0.38 mg/dL) had inducible ischemia, compared with 45% (79/177) in the lower 4 categories combined (adjusted odds ratio 4.2; 95% confidence interval 1.6 to 11; P=0.004). However, this association differed in users and nonusers of beta-blockers and statins. Among 89 participants who did not use beta-blockers, 93% in the highest CRP category had exercise-induced ischemia, compared with 42% in the lower 4 categories (P=0.03). Among 67 participants who did not use statins, 94% in the highest CRP category had exercise-induced ischemia, compared with 44% in the lower 4 categories (P=0.009). We did not observe a significant association between CRP and ischemia among participants who were treated with either of these medications., Conclusion: Elevated CRP levels are associated with inducible ischemia in patients with stable coronary disease, particularly among those not treated with beta-blockers or statins.

ImportanceLevels of high-sensitivity cardiac troponin T (hs-cTnT) predict secondary cardiovascular events in patients with stable coronary heart disease.ObjectivesTo determine the association of hs-cTnT levels with structural and functional measures of heart disease and the extent to which these measures explain the relationship between hs-cTnT and secondary events.DesignWe measured serum concentrations of hs-cTnT and performed exercise treadmill testing with stress echocardiography in a prospective cohort study of outpatients with coronary heart disease who were enrolled from September 11, 2000, through December 20, 2002, and followed up for a median of 8.2 years.SettingTwelve outpatient clinics in the San Francisco Bay Area.ParticipantsNine hundred eighty-four patients with stable coronary heart disease.Main outcomes and measuresCardiovascular events (myocardial infarction, heart failure, or cardiovascular death), determined by review of medical records and death certificates.ResultsOf 984 participants, 794 (80.7%) had detectable hs-cTnT levels. At baseline, higher hs-cTnT levels were associated with greater inducible ischemia and worse left ventricular ejection fraction, left atrial function, diastolic function, left ventricular mass, and treadmill exercise capacity. During follow-up, 317 participants (32.2%) experienced a cardiovascular event. After adjustment for clinical risk factors, baseline cardiac structure and function, and other biomarkers (N-terminal portion of the prohormone of brain-type natriuretic peptide and C-reactive protein levels), each doubling in hs-cTnT level remained associated with a 37% higher rate of cardiovascular events (hazard ratio, 1.37 [95% CI, 1.14-1.65]; P = .001).Conclusions and relevanceIn outpatients with stable coronary heart disease, higher hs-cTnT levels were associated with multiple abnormalities of cardiac structure and function but remained independently predictive of secondary events. These findings suggest that hs-cTnT levels may detect an element of risk that is not captured by existing measures of cardiac disease severity.

Background: Patients with posttraumatic stress disorder (PTSD) are at increased risk for cardiovascular disease (CVD), but few studies have included objective measures of CVD and how PTSD causes CVD remains unknown. We sought to determine the association between PTSD and objectively assessed CVD and examine potential underlying mechanisms. Methods: Outpatients from two Veterans Affairs Medical Centers were enrolled from 2008 to 2010. Posttraumatic stress disorder was identified using the Clinician Administered PTSD Scale, and standardized exercise treadmill tests were performed to detect myocardial ischemia. Results: Of the 663 participants with complete data, ischemia was present in 17% of patients with PTSD versus 10% of patients without PTSD (p = .006). The association between PTSD and ischemia remained significant after adjusting for potential confounders (age, sex, prior CVD) and mediators (traditional cardiac risk factors, C-reactive protein, obesity, alcohol use, sleep quality, social support, and depression), adjusted odds ratio (OR) 2.42, 95% confidence interval (CI) 1.39 to 4.22, p = .002. Findings remained significant when those with prior CVD were excluded (fully adjusted OR 2.24, 95% CI 1.20–4.18, p = .01) and when continuous PTSD symptom score was used as the predictor (fully adjusted OR per 10-point change in Clinician Administered PTSD Scale score 1.12, 95% CI 1.03–1.22, p = .01). Conclusions: Posttraumatic stress disorder was associated with ischemic changes on exercise treadmill tests independent of traditional cardiac risk factors, C-reactive protein, and several health behaviors and psychosocial risk factors, suggesting additional mechanisms linking PTSD and ischemia should be explored. The association of PTSD and ischemia among patients without known CVD highlights an opportunity for early interventions to prevent progression of cardiovascular disease. [ABSTRACT FROM AUTHOR]

Introduction: C-reactive protein (CRP) level stratifies risk for events in coronary heart disease (CHD) and is independently associated with increased risk of heart failure (HF). It is unknown how CHD-associated risk of stroke, HF, and all-cause mortality is affected by CRP and if it is modifiable. Hypothesis: The risk associated with elevated CRP in patients with CHD can be modified by beta blocker and statin use. Methods: A cohort of outpatients with CHD from the Heart and Soul Study (N = 985) had serum CRP measured. Outcomes after 7.1 years ± 3.2 years including non-fatal MI, HF, stroke, cardiovascular death, and all-cause mortality were analyzed and modifying factors were compared using Kaplan Meier estimates. Results: Elevated CRP level > 3mg/L (CRPH) was associated with an increased risk of stroke (hazard ratio (HR) 2.4, p = 0.01), HF (HR 1.9, p = 0.001), and all-cause mortality (HR 1.4, p = 0.005), compared to low CRP level < 3mg/L (CRPL). CRPH patients not taking a statin had more HF events (HR 2.9, p = 0.001) and increased risk of all-cause mortality (HR 1.5, p = 0.045) compared to CRPL patients not taking a statin. CRPH patients not taking a beta blocker had more HF events (HR 2.5, p = 0.001) and increased risk of all-cause mortality (HR 1.7, p = 0.003) compared to CRPL patients not taking a beta-blocker. CRPH patients on neither beta blocker nor statin had more HF events (HR 2.7, p = 0.002) and increased risk of all-cause mortality (HR 2.0, p = 0.004) compared to CRPH patients on both medications. CRPL patients on both beta blocker and statin had reduced risk of all-cause mortality (HR 0.6, p = 0.04) compared to CRPL patients on neither medication. Conclusions: Among outpatients with CHD, CRPH is associated with an increased risk of adverse CHD outcomes including stroke, HF, and all-cause mortality. The risk of HF and all-cause mortality is considerable but modified by beta blockers and statins. Among those with CRPL, the use of beta blockers and statin reduces risk of all-cause mortality. [ABSTRACT FROM AUTHOR]