Biomedical subjects

Richard A Kronmal

Publications and source records attributed to Richard A Kronmal.

At least 19 recordsLinked to original sources

PubMed2006

Leukocyte telomere length and cardiovascular disease in the cardiovascular health study.

The telomere length of replicating somatic cells is inversely correlated with age and has been reported to be associated cross-sectionally with cardiovascular disease (CVD). Leukocyte telomere length, as expressed by mean terminal restriction fragment (TRF) length, was measured in 419 randomly selected participants from the Cardiovascular Health Study, comprising a community-dwelling cohort recruited in four US communities. The authors investigated associations between TRF length and selected measures of subclinical CVD/risk factors for CVD (data were collected at the 1992/1993 clinic visit) and incident CVD (ascertained through June 2002). In these participants (average age = 74.2 years (standard deviation, 5.2)), mean TRF length was 6.3 kilobase pairs (standard deviation, 0.62). Significant or borderline inverse associations were found between TRF length and diabetes, glucose, insulin, diastolic blood pressure, carotid intima-media thickness, and interleukin-6. Associations with body size and C-reactive protein were modified by gender and age, occurring only in men and in participants aged 73 years or younger. In younger (but not older) participants, each shortened kilobase pair of TRF corresponded with a threefold increased risk of myocardial infarction (hazard ratio = 3.08, 95% confidence interval: 1.22, 7.73) and stroke (hazard ratio = 3.22, 95% confidence interval: 1.29, 8.02). These results support the hypotheses that telomere attrition may be related to diseases of aging through mechanisms involving oxidative stress, inflammation, and progression to CVD.

Aged↗

PubMed2006

Laboratory parameter profiles among patients with cystic fibrosis.

BACKGROUND: Clinical trials in cystic fibrosis (CF) currently use laboratory-specific reference ranges to evaluate chemistry and hematology measurements. Laboratory-specific normal reference ranges may not accurately reflect what is abnormal but clinically insignificant among CF patients. METHODS: To address this concern, data from the Phase III trial of inhaled tobramycin in CF patients was used to describe the distribution and variability of laboratory parameters. The laboratory specimens were analyzed at a central laboratory after being obtained at baseline and throughout the 24-week trial. RESULTS: At the time of entry into the clinical trial, 91% (463 of 508) of patients had at least a single value outside the normal range. Liver function tests (AST, ALT) were above the normal range in 16% and 12% of the patients respectively, with 2.4% of patients having an AST>2.0 times the upper limit of normal. Of the 243 patients on placebo, 242 (99.6%) had at least one laboratory parameter that changed from normal to abnormal during the 24-week follow-up period. Of those same placebo patients, 11.5% (N=28) had a laboratory parameter change from a Common Toxicity Criteria (CTC) grade 0 to grade 2 or higher during follow-up. CONCLUSIONS: Patients with CF frequently have laboratory values outside the normal range and have significant longitudinal variability of laboratory values. Interpretation of adverse events in the clinical trial setting may be complicated by the underlying high rates of some laboratory abnormalities in the CF population. This data was presented in poster format at the American Thoracic Society International Conference, Atlanta, USA, 2002, appearing subsequently in the Conference proceedings [Goss CH, Mayer-Hamblett N, Yunker A, Waltz DA, Kronmal RA, Ramsey BW. Laboratory parameter profiles among patients with cystic fibrosis. Am J Rep Crit Care Med 2002;165(8):A283].

Adolescent↗

PubMed2006

Genetic Susceptibility to Prostate Cancer: Prostate-specific Antigen and its Interaction with the Androgen Receptor (United States).

OBJECTIVE: To determine whether directly observed prostate-specific antigen (PSA) promoter diploid haplotype, either alone or in conjunction with androgen receptor (AR) genotype, is associated with prostate cancer risk. METHODS: We conducted a case-control study nested within the US population-based Cardiovascular Health Study cohort. Incident prostate cancers were identified by linkage to cancer registry records for the years 1989-2000. We genotyped 193 cases and 391 controls for the PSA -252 G/A and -158 G/A SNPs and the AR CAG microsatellite, and developed methods to directly determine proximal PSA promoter haplotypes. Exact logistic regression was used to estimate odds ratios and significance levels. RESULTS: No significant associations were observed between PSA diplotype and prostate cancer overall. Short (< 20) AR CAG repeat lengths were associated with modest increases in the risk of prostate cancer (OR, 1.46; 95% CI, 0.97-2.19; p = 0.071) that were significant for advanced disease (OR, 1.82; 95% CI, 1.02-3.26; p = 0.044). Men who possessed two copies of the PSA*2 (-252G/-158G) haplotype and short AR CAG repeat lengths had a 4-fold (95% CI, 1.05-20.75; exact p = 0.040) increased risk of prostate cancer, and a 7-fold (95% CI, 1.25-39.78; exact p = 0.026) increased risk of advanced disease. CONCLUSIONS: We found evidence that the PSA*2*2 diplotype in combination with short AR CAG alleles increases a man's risk of developing prostate cancer. These findings support an etiologic role in prostate cancer of genetic interactions between polymorphisms that increase AR transactivation strength and those that alter the regulatory regions of target genes such as PSA that are responsive to androgen stimulation.

Aged↗

PubMed2006

Regional diastolic dysfunction in individuals with left ventricular hypertrophy measured by tagged magnetic resonance imaging--the Multi-Ethnic Study of Atherosclerosis (MESA).

BACKGROUND: Impairment of global diastolic function is considered to be the mechanism of congestive heart failure in individuals with preserved systolic left ventricular (LV) function. Left ventricular hypertrophy (LVH) is known to be a risk factor for congestive heart failure with preserved systolic function, and this process may begin as a regional process. We investigated whether regional LV diastolic function measured by magnetic resonance tagging is altered in asymptomatic participants of the MESA with LVH and preserved systolic LV function. METHODS: Regional systolic and diastolic strain rates were calculated from strain data in 218 participants of the MESA study. Circumferential strain was calculated from the midwall layer of the septum, anterior, lateral, and inferior walls at mid-LV level. Global LV function measures were studied by magnetic resonance imaging in 4291 MESA participants. Left ventricular hypertrophy for men and women was defined from the MESA population using previously established Framingham criteria. RESULTS: Global systolic function was slightly less in the LVH (ejection fraction = 0.66 +/- 0.10) versus the non-LVH group (ejection fraction = 0.69 +/- 0.07, P < .001). Stepwise regression analyses showed a direct relationship between regional diastolic dysfunction and increasing LV mass. Regional systolic strain and strain rate measures from participants with LVH were not significantly different from those without LVH. However, regional diastolic strain rate was significantly reduced in participants with LVH (1.5 +/- 1.1 s(-1)) compared with the non-LVH group (2.2 +/- 1.1 s(-1), P < .001) regardless of age or sex. CONCLUSIONS: Left ventricular hypertrophy is associated with regional diastolic dysfunction in individuals without evidence of clinical cardiovascular disease and preserved systolic function. Magnetic resonance imaging tagging provides detailed quantification of regional diastolic function noninvasively.

Aged↗

PubMed2006

Mortality in pharmacologically treated older adults with diabetes: the Cardiovascular Health Study, 1989-2001.

BACKGROUND: Diabetes mellitus (DM) confers an increased risk of mortality in young and middle-aged individuals and in women. It is uncertain, however, whether excess DM mortality continues beyond age 75 years, is related to type of hypoglycemic therapy, and whether women continue to be disproportionately affected by DM into older age. METHODS AND FINDINGS: From the Cardiovascular Health Study, a prospective study of 5,888 adults, we examined 5,372 participants aged 65 y or above without DM (91.2%), 322 with DM treated with oral hypoglycemic agents (OHGAs) (5.5%), and 194 with DM treated with insulin (3.3%). Participants were followed (1989-2001) for total, cardiovascular disease (CVD), coronary heart disease (CHD), and non-CVD/noncancer mortality. Compared with non-DM participants, those treated with OHGAs or insulin had adjusted hazard ratios (HRs) for total mortality of 1.33 (95% confidence interval [CI], 1.10 to 1.62) and 2.04 (95% CI, 1.62 to 2.57); CVD mortality, 1.99 (95% CI, 1.54 to 2.57) and 2.16 (95% CI, 1.54 to 3.03); CHD mortality, 2.47 (95% CI, 1.89 to 3.24) and 2.75 (95% CI, 1.95 to 3.87); and infectious and renal mortality, 1.35 (95% CI, 0.70 to 2.59) and 6.55 (95% CI, 4.18 to 10.26), respectively. The interaction of age (65-74 y versus > or =75 y) with DM was not significant. Women treated with OHGAs had a similar HR for total mortality to men, but a higher HR when treated with insulin. CONCLUSIONS: DM mortality risk remains high among older adults in the current era of medical care. Mortality risk and type of mortality differ between OHGA and insulin treatment. Women treated with insulin therapy have an especially high mortality risk. Given the high absolute CVD mortality in older people, those with DM warrant aggressive CVD risk factor reduction.

Administration, Oral↗

PubMed2005

Distribution of coronary artery calcium by race, gender, and age: results from the Multi-Ethnic Study of Atherosclerosis (MESA).

BACKGROUND: Coronary artery calcium (CAC) has been demonstrated to be associated with the risk of coronary heart disease. The Multi-Ethnic Study of Atherosclerosis (MESA) provides a unique opportunity to examine the distribution of CAC on the basis of age, gender, and race/ethnicity in a cohort free of clinical cardiovascular disease and treated diabetes. METHODS AND RESULTS: MESA is a prospective cohort study designed to investigate subclinical cardiovascular disease in a multiethnic cohort free of clinical cardiovascular disease. The percentiles of the CAC distribution were estimated with nonparametric techniques. Treated diabetics were excluded from analysis. There were 6110 included in the analysis, with 53% female and an average age of 62 years. Men had greater calcium levels than women, and calcium amount and prevalence were steadily higher with increasing age. There were significant differences in calcium by race, and these associations differed across age and gender. For women, whites had the highest percentiles and Hispanics generally had the lowest; in the oldest age group, however, Chinese women had the lowest values. Overall, Chinese and black women were intermediate, with their order dependent on age. For men, whites consistently had the highest percentiles, and Hispanics had the second highest. Blacks were lowest at the younger ages, and Chinese were lowest at the older ages. At the MESA public website (http://www.mesa-nhlbi.org), an interactive form allows one to enter an age, gender, race/ethnicity, and CAC score to obtain a corresponding estimated percentile. CONCLUSIONS: The information provided here can be used to examine whether a patient has a high CAC score relative to others with the same age, gender, and race/ethnicity who do not have clinical cardiovascular disease or treated diabetes.

Age Factors↗

PubMed2005

Azithromycin for the secondary prevention of coronary events.

BACKGROUND: Epidemiologic, laboratory, animal, and clinical studies suggest that there is an association between Chlamydia pneumoniae infection and atherogenesis. We evaluated the efficacy of one year of azithromycin treatment for the secondary prevention of coronary events. METHODS: In this randomized, prospective trial, we assigned 4012 patients with documented stable coronary artery disease to receive either 600 mg of azithromycin or placebo weekly for one year. The participants were followed for a mean of 3.9 years at 28 clinical centers throughout the United States. RESULTS: The primary end point, a composite of death due to coronary heart disease, nonfatal myocardial infarction, coronary revascularization, or hospitalization for unstable angina, occurred in 446 of the participants who had been randomly assigned to receive azithromycin and 449 of those who had been randomly assigned to receive placebo. There was no significant risk reduction in the azithromycin group as compared with the placebo group with regard to the primary end point (risk reduction, 1 percent [95 percent confidence interval, -13 to 13 percent]). There were also no significant risk reductions with regard to any of the components of the primary end point, death from any cause, or stroke. The results did not differ when the participants were stratified according to sex, age, smoking status, presence or absence of diabetes mellitus, or C. pneumoniae serologic status at baseline. CONCLUSIONS: A one-year course of weekly azithromycin did not alter the risk of cardiac events among patients with stable coronary artery disease.

Aged↗

PubMed2005

Skin tissue cholesterol assay correlates with presence of coronary calcium.

BACKGROUND: Keratinocytes maintain cholesterol homoeostasis using LDL and HDL-scavenger receptor pathways implicated in atherosclerosis. We tested whether skin tissue cholesterol (SkTC) is associated with subclinical atherosclerosis, assessed using carotid intima-medial thickness (IMT) and coronary artery calcification (CAC). METHODS: Two hundred and twenty two subjects were recruited from the Baltimore site of the Multi-Ethnic Study of Atherosclerosis (MESA). Baseline MESA examination included fasting blood collection, IMT measurement by B-mode ultrasound and CAC determination by helical CT. SkTC was measured using the Cholesterol 1, 2, 3 kit (IMI Inc., Canada). RESULTS: SkTC was significantly higher if CAC was present in Caucasians (p = 0.04) but not African-Americans. SkTC was not significantly correlated with IMT in either group. Using multiple logistic regression adjusting for age, sex and serum lipids, a 1-standard deviation higher SkTC was associated with 187% higher odds of the presence of CAC in Caucasians (p < 0.01) but no significant difference in odds for African-Americans. In subjects in whom CAC was present, the extent of CAC was not related to the SkTC in multiple linear regressions. CONCLUSIONS: SkTC was associated with the presence of CAC independently of serum lipids/lipoproteins in Caucasians but not African-Americans. SkTC may provide a useful indicator of subclinical atherosclerosis in Caucasians.

Black or African American↗

PubMed2005

Improving the estimation of change from baseline in a continuous outcome measure in the clinical trial setting.

In many clinical trials, the primary focus is whether treatment groups differ with respect to the change from baseline to end of therapy in a continuous response variable. Randomized clinical trials often use a repeated measures design in which subjects are followed-up at fixed times throughout the study. With this design, testing for differences between treatment groups with respect to the average change from baseline to end of therapy in the response variable is equivalent to testing for differences between the rates of change in the response variable, assuming the rates of change in each treatment group are linear. This analysis can be performed quite easily using methods such as generalized estimating equations (GEE). However, if the rate of change in the response cannot be assumed linear, the average change from baseline is many times calculated using simply differences between baseline and final measurements and additional data points are not included in the analysis. Instead, we propose using all available data in a repeated measures model that is based on the nonlinear treatment response pattern to estimate the average change from baseline to end of therapy in each treatment group. GEE with robust variance estimation is used for obtaining these model-based estimates of the treatment effect and a simple test for appropriateness of the model is presented. The GEE model presented, in conjunction with the test for appropriateness of the model, form the basis for an adaptive analysis approach for determining the method of estimation of the primary endpoint. This approach results in more efficient estimates of the treatment effect when the response pattern is specified correctly and minimizes the bias in the estimate when the hypothesized response pattern is misspecified. We are motivated by examples in the cystic fibrosis (CF) clinical trial setting and demonstrate the potential for this approach in reducing the sample size required for future CF clinical trials.

Computer Simulation↗

PubMed2005

Incidence of cardiovascular disease in older Americans: the cardiovascular health study.

OBJECTIVES: To estimate incidence rates of major cardiovascular disease (CVD) in older Americans. DESIGN: Longitudinal cohort study using prospectively collected data on cardiovascular events. SETTING: Four U.S. communities in the Cardiovascular Health Study (CHS). PARTICIPANTS: Five thousand eight hundred eighty-eight participants in CHS, aged 65 or older at enrollment, including 3,393 women (581 African American) and 2,495 men (343 African American). MEASUREMENTS: At semiannual contacts, participants reported any occurrence of clinical CVD. Medical records were obtained and adjudicated to confirm diagnosis of CVD. RESULTS: During 10 years of follow-up, incidence of coronary heart disease (CHD) per 1,000 person-years was 39.6 (95% confidence interval (CI)=36.4-43.1) in men and 22.3 (95% CI=20.4-24.2) in women. Cumulative event rates for CHD and myocardial infarction for women aged 75 and older at baseline were similar to those for men aged 65 to 74. The overall incidence of stroke was similar for men and women (14.7 (95% CI=13.0-16.6) and 13.7 (95% CI=12.4-15.1) per 1,000 person-years, respectively), but the risk of stroke increased with age more rapidly in women, resulting in a greater cumulative event rate for stroke in women than in men aged 75 and older. The incidence of congestive heart failure increased 9% with each year of age over 65 and was greater than 6% per year in Caucasian men and women aged 85 and older at baseline. Rates were similar in African Americans and Caucasians. CONCLUSION: The occurrence of new CVD in older Americans is high, indicating that preventive efforts need to be maintained into older ages.

Black or African American↗

PubMed2005

Measuring coronary calcium on CT images adjusted for attenuation differences.

PURPOSE: To quantify scanner and participant variability in attenuation values for computed tomographic (CT) images assessed for coronary calcium and define a method for standardizing attenuation values and calibrating calcium measurements. MATERIALS AND METHODS: Institutional review board approval and participant informed consent were obtained at all study sites. An image attenuation adjustment method involving the use of available calibration phantom data to define standard attenuation values was developed. The method was applied to images from two population-based multicenter studies: the Coronary Artery Risk Development in Young Adults study (3041 participants) and the Multi-Ethnic Study of Atherosclerosis (6814 participants). To quantify the variability in attenuation, analysis of variance techniques were used to compare the CT numbers of standardized torso phantom regions across study sites, and multivariate linear regression models of participant-specific calibration phantom attenuation values that included participant age, race, sex, body mass index (BMI), smoking status, and site as covariates were developed. To assess the effect of the calibration method on calcium measurements, Pearson correlation coefficients between unadjusted and attenuation-adjusted calcium measurements were computed. Multivariate models were used to examine the effect of sex, race, BMI, smoking status, unadjusted score, and site on Agatston score adjustments. RESULTS: Mean attenuation values (CT numbers) of a standard calibration phantom scanned beneath participants varied significantly according to scanner and participant BMI (P < .001 for both). Values were lowest for Siemens multi-detector row CT scanners (110.0 HU), followed by GE-Imatron electron-beam (116.0 HU) and GE LightSpeed multi-detector row scanners (121.5 HU). Values were also lower for morbidly obese (BMI, > or =40.0 kg/m(2)) participants (108.9 HU), followed by obese (BMI, 30.0-39.9 kg/m(2)) (114.8 HU), overweight (BMI, 25.0-29.9 kg/m(2)) (118.5 HU), and normal-weight or underweight (BMI, <25.0 kg/m(2)) (120.1 HU) participants. Agatston score calibration adjustments ranged from -650 to 1071 (mean, -8 +/- 50 [standard deviation]) and increased with Agatston score (P < .001). The direction and magnitude of adjustment varied significantly according to scanner and BMI (P < .001 for both) and were consistent with phantom attenuation results in that calibration resulted in score decreases for images with higher phantom attenuation values. CONCLUSION: Image attenuation values vary by scanner and participant body size, producing calcium score differences that are not due to true calcium burden disparities. Use of calibration phantoms to adjust attenuation values and calibrate calcium measurements in research studies and clinical practice may improve the comparability of such measurements between persons scanned with different scanners and within persons over time.

Algorithms↗

PubMed2004

The association of fasting glucose levels with congestive heart failure in diabetic adults > or =65 years: the Cardiovascular Health Study.

OBJECTIVES: The purpose of this study was to determine if fasting glucose levels are an independent risk factor for congestive heart failure (CHF) in elderly individuals with diabetes mellitus (DM) with or without coronary heart disease (CHD). BACKGROUND: Diabetes mellitus and CHF frequently coexist in the elderly. It is not clear whether fasting glucose levels in the setting of DM are a risk factor for incident CHF in the elderly. METHODS: A cohort of 829 diabetic participants, age > or =65 years, without prevalent CHF, was followed for five to eight years. The Cox proportional hazards modeling was used to determine the risk of CHF by fasting glucose levels. The cohort was categorized by the presence or absence of prevalent CHD. RESULTS: For a 1 standard deviation (60.6 mg/dl) increase in fasting glucose, the adjusted hazard ratios for incident CHF among participants without CHD at baseline, with or without an incident myocardial infarction (MI) or CHD event on follow-up, was 1.41 (95% confidence interval 1.24 to 1.61; p < 0.0001). Among those with prevalent CHD at baseline, with or without another incident MI or CHD event on follow-up, the corresponding adjusted hazard ratio was 1.27 (95% confidence interval 1.02 to 1.58; p < 0.05). CONCLUSIONS: Among older adults with DM, elevated fasting glucose levels are a risk factor for incident CHF. The relationship of fasting glucose to CHF differs somewhat by the presence or absence of prevalent CHD.

Aged↗

PubMed2004

Predictors of falling cholesterol levels in older adults: the Cardiovascular Health Study.

PURPOSE: To estimate 4-year change in serum total cholesterol levels in a population-based sample of older adults and identify independent predictors of cholesterol decline. METHODS: Prospective study of 2837 adults aged 65 years and older with serum cholesterol measured in 1992-1993 and 1996-1997. RESULTS: Mean serum cholesterol levels declined 6.3 mg/dl between the two examinations. Declines were greater in white (-7.3 mg/dl) than black (-1.4 mg/dl) participants and in those in good/excellent health (-0.9 mg/dl) vs. fair/poor health (-3.1 mg/dl; both p < 0.01). Factors associated with greater decline on multivariate analysis included age, male gender, and higher white cell count, albumin, and baseline cholesterol. Cholesterol levels declined 2.0 mg/dl per 6 year increment in baseline age and 6.8 mg/dl more in men than women after adjustment for other factors. C-reactive protein levels were unrelated to cholesterol change. CONCLUSION: Declining cholesterol levels were associated with male gender, advanced age, weight loss, and white blood cell count but not with C-reactive protein levels. The role of declining cholesterol synthesis, due to as yet undefined age-related changes or to cytokine-mediated reductions related to illness, should be examined to help clarify the mechanisms of the sometimes marked declines in cholesterol levels observed at advanced ages.

Black or African American↗

PubMed2004

The association between lipid levels and the risks of incident myocardial infarction, stroke, and total mortality: The Cardiovascular Health Study.

OBJECTIVES: To assess the association between lipid levels and cardiovascular events in older adults. DESIGN: A prospective population-based study. SETTING: Four field centers in U.S. communities. PARTICIPANTS: A total of 5,201 adults aged 65 and older living in U.S. communities, plus a recruitment of 687 African Americans 3 years later. MEASUREMENTS: Fasting lipid measures included low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol, and triglycerides. RESULTS: At baseline, 1,954 men and 2,931 women were at risk for an incident myocardial infarction (MI) or stroke. During an average 7.5-year follow-up, 436 subjects had a coronary event, 332 had an ischemic stroke, 104 a hemorrhagic stroke, and 1,096 died. After adjustment, lipid measures were not major predictors of the outcomes of MI, ischemic stroke, hemorrhagic stroke, and total mortality. For total cholesterol and LDL-C, the associations with MI and ischemic stroke were only marginally significant. HDL-C was inversely associated with MI risk (hazard ratio=0.85 per standard deviation of 15.7 mg/dL, 95% confidence interval=0.76-0.96). For the outcome of ischemic stroke, high levels of HDL-C were associated with a decreased risk in men but not women. Lipid measures were generally only weakly associated with the risks of hemorrhagic stroke or total mortality. CONCLUSION: In this population-based study of older adults, most lipid measures were weakly associated with cardiovascular events. The association between low HDL-C and increased MI risk was nonetheless strong and consistent.

Black or African American↗

PubMed2004

The relationship of fasting serum radioimmune insulin levels to incident coronary heart disease in an insulin-treated diabetic cohort.

It is not known whether insulin levels, in the setting of insulin treatment, are an independent risk factor for coronary heart disease (CHD). We studied a cohort of 116 insulin-treated individuals, 65 yr or older, who were followed for 5.6-9 yr. All were free of CHD at baseline. There were 47 incident CHD events. In Cox proportional hazards modeling, with fasting immune-reactive insulin levels as a continuous variable, the hazard ratio for CHD was statistically significant (P < 0.0001). When insulin levels were divided into intervals, those in the third interval [43-150 microU/ml (258-900 pmol/liter)] had an adjusted 30% increased relative risk (95% confidence interval, 0.57, 2.98) compared with those in the first interval [<20 microU/ml (<120 pmol/liter)]. Those in the fourth interval [151-400 microU/ml (906-2400 pmol/liter)] had an adjusted 5.6-fold increased risk (2.3-13.1; P < 0.0001). Approximately 15% of the cohort had such elevated insulin levels. Immune-reactive insulin levels were strongly correlated with specific insulin, proinsulin, and insulin antibody levels. Markedly elevated fasting immune-reactive insulin levels were an independent risk factor for CHD in this study of insulin-treated older adults. These observational findings should be confirmed through larger prospective studies, given their implications for insulin therapy.

Aged↗

PubMed2003

Inflammation as a risk factor for atrial fibrillation.

BACKGROUND: The presence of systemic inflammation determined by elevations in C-reactive protein (CRP) has been associated with persistence of atrial fibrillation (AF). The relationship between CRP and prediction of AF has not been studied in a large population-based cohort. METHODS AND RESULTS: CRP measurement and cardiovascular assessment were performed at baseline in 5806 subjects enrolled in the Cardiovascular Health Study. Patients were followed up for a mean of 6.9+/-1.6 (median 7.8) years. AF was identified by self-reported history and ECGs at baseline and by ECGs and hospital discharge diagnoses at follow-up. Univariate and multivariate analyses were used to assess CRP as a predictor of baseline and future development of AF. At baseline, 315 subjects (5%) had AF. Compared with subjects in the first CRP quartile (<0.97 mg/L), subjects in the fourth quartile (>3.41 mg/L) had more AF (7.4% versus 3.7%, adjusted OR 1.8, 95% CI 1.2 to 2.5; P=0.002). Of 5491 subjects without AF at baseline, 897 (16%) developed AF during follow-up. Baseline CRP predicted higher risk for developing future AF (fourth versus first quartile adjusted hazard ratio 1.31, 95% CI 1.08 to 1.58; P=0.005). When treated as a continuous variable, elevated CRP predicted increased risk for developing future AF (adjusted hazard ratio for 1-SD increase, 1.24; 95% CI 1.11 to 1.40; P<0.001). CONCLUSIONS: CRP is not only associated with the presence of AF but may also predict patients at increased risk for future development of AF.

Aged↗

PubMed2003

Alcohol consumption and carotid atherosclerosis in older adults: the Cardiovascular Health Study.

OBJECTIVE: The association of alcohol use with atherosclerosis is inconsistent in previous studies. METHODS AND RESULTS: For the Cardiovascular Health Study, 5888 adults aged 65 years and older underwent a standardized interview and examination. They reported beer, wine, and liquor use individually and underwent B-mode ultrasonography to determine internal and common carotid intima-media thickness (IMT). We compared composite carotid IMT values cross-sectionally using linear regression to adjust for demographic and clinical characteristics. Among 4247 participants free of cardiovascular disease, consumers of 1 to 6 drinks per week had 0.07+/-0.04-mm lower composite IMT and consumers of 14 or more drinks per week had 0.07+/-0.05-mm higher IMT than abstainers (P quadratic trend=0.02). We found similar relationships using internal and common carotid thickness measures and among men and women. The higher IMT associated with heavier alcohol use was particularly strong among 1592 participants with confirmed cardiovascular disease (0.24+/-0.09 mm greater than abstainers). Controlling for HDL cholesterol levels reduced the effect on composite IMT among consumers of 1 to 6 drinks per week by 22%. CONCLUSIONS: Relative to older adults who abstain from alcohol, consumption of 1 to 6 drinks per week had an inverse association with carotid atherosclerosis whereas consumption of 14 or more drinks had a positive association.

Aged↗

PubMed2003

Lessons from the Stroke Prevention in Atrial Fibrillation trials.

Atrial fibrillation predisposes to left atrial thrombus formation and carries a sixfold increased risk for stroke. Antithrombotic therapies are the mainstay for stroke prevention. The National Institute of Neurological Disorders and Stroke-sponsored Stroke Prevention in Atrial Fibrillation (SPAF) studies assessed the value of warfarin, aspirin, and their combination for preventing stroke in six multicenter trials involving 3950 participants. This review presents the major results and implications, which offer unique perspectives on antithrombotic therapies for stroke prevention in atrial fibrillation. Warfarin and aspirin reduce stroke. Anticoagulation substantially benefits high-risk patients with atrial fibrillation, while many younger patients with atrial fibrillation have a low stroke rate when given aspirin. Pathogenetic and transesophageal echocardiographic correlations shed light on mechanisms by which antithrombotic agents prevent stroke. Warfarin inhibits formation of atrial appendage thrombi and markedly reduces cardioembolic strokes, while aspirin primarily prevents smaller, noncardioembolic strokes. The SPAF III stroke risk stratification scheme has been validated for identifying patients with high versus moderate versus low risk for stroke. Women with atrial fibrillation benefit from anticoagulation significantly more than men do. Many elderly patients with recurrent paroxysmal atrial fibrillation have high rates of stroke. Antithrombotic prophylaxis should be individualized on the basis of the estimated risk for stroke during aspirin therapy and the risk for bleeding during anticoagulation. Overall, nearly one third of patients with atrial fibrillation are low risk and should be treated with aspirin, and about one third are high risk and should receive warfarin if it can be given safely. For patients at moderate risk for stroke, patient preferences and access to reliable anticoagulation monitoring are particularly relevant.

Anticoagulants↗