Biomedical subjects

Gerardo Heiss

Publications and source records attributed to Gerardo Heiss.

79 records · Page 5Linked to original sources

PubMed2002

B-mode ultrasound-detected carotid artery lesions with and without acoustic shadowing and their association with markers of inflammation and endothelial activation: the atherosclerosis risk in communities study.

In a cross-sectional study of 8695 men and women free of clinical CVD, aged 45-64 years at the 1987-1989 baseline Atherosclerosis Risk in Communities (ARIC) study exam, we examined the relationship between carotid artery lesions (CALs), with and without acoustic shadowing (AS) as an index of plaque mineralization, to systemic markers of inflammation and markers of endothelial function, including endothelial adhesion molecules. A three-level variable, based on the presence of extracranial CALs and AS, identified by B-mode ultrasound of six 1 cm arterial segments, defined the outcome. Among subjects without evidence of AS, after controlling for age, gender, ethnicity, study site, body mass index, hypertension, diabetes, and smoking status, CALs were associated with systemic markers of inflammation, including higher levels of fibrinogen [OR=1.24 (95% CI: 1.09, 1.40)] and white blood cell count [OR=1.37 (95% CI: 1.21, 1.56)]. Among subjects with a CAL, after controlling for the above risk factors as well as mean far wall intima-media thickness, AS was associated with higher levels of von Willebrand factor [OR=1.38 (95% CI: 1.10, 1.74)], a marker of endothelial activation. Associations with endothelial adhesion molecules were inconsistent. Further studies aimed at elucidating the mechanisms of arterial mineralization are warranted.

Arteriosclerosis↗

PubMed2002

Hyperhomocyst(e)inemia and hemostatic factors: the atherosclerosis risk in communities study.

PURPOSE: To determine whether homocyst(e)ine (H(e)) is related to hemostatic factors in a population-based sample without evidence of cardiovascular disease. METHODS: A subsample of 660 participants--67 African-American women, 53 African-American men, 201 white women, and 339 white men--was selected from the Atherosclerosis Risk in Communities Study baseline cohort. This was based on carotid intimal-medial wall thickness above the 90th percentile or below the 75th percentile of the population distribution, assessed by B-mode ultrasonography. Unadjusted and multivariable-adjusted associations between fasting plasma H(e) and the hemostatic factors fibrinogen, factor VII:c, factor VIII:c, protein C antigen, hematocrit, platelet count, beta-thromboglobulin (beta-TG), tissue plasminogen activator (tPA), PAI-1, D-dimer, and lipoprotein[a] were examined. RESULTS: Mean age-adjusted H(e) was positively, albeit weakly, correlated with beta-TG, tPA, hematocrit, D-dimer and PAI-1; inversely correlated with protein C; and was higher in smokers, men and African-Americans. In multivariable regression, beta-TG, tPA, and factor VII:c were positively associated with H(e), as well as age, black race, male sex, and current cigarette smoking. CONCLUSIONS: These cross-sectional data for a biracial group of middle-aged individuals suggest that H(e) levels falling below values consistent with homocyst(e)inemia are associated with several prothrombotic factors after adjustment for sociodemographic factors. If H(e) change is antecedent to altered hemostasis, FDA-mandated fortification of grain products with folic acid for prevention of fetal neural tube defects may lead to both reduced plasma H(e) levels and improved hemostatic profiles.

Age Factors↗

PubMed2002

Prevalence of premature ventricular contractions in a population of African American and white men and women: the Atherosclerosis Risk in Communities (ARIC) study.

BACKGROUND: The distribution or the causes of premature ventricular contractions (PVCs) in diverse populations are not fully known. We describe the prevalence of PVCs on a 2-minute electrocardiogram (ECG) in adults to determine whether hypertension has an important association with such PVCs. METHODS: A cross-sectional analysis of the 15,792 individuals (aged 45-65 years) from the four US communities participating at visit 1 of the Atherosclerosis Risk In Communities (ARIC) study was performed. Multiple logistic regression was used to determine the association of PVCs with potential causal predictors of PVCs. RESULTS: Based on a 2-minute ECG, PVCs are present in >6% of middle-aged adults. Increasing age, the presence of heart disease, faster sinus rates, African American ethnicity, male sex, lower educational attainment, and lower serum magnesium or potassium levels are directly related to PVC prevalence. Independently of these factors, hypertension is associated with a 23% increase in the prevalence of PVCs. CONCLUSIONS: The prevalence of PVCs on a 2-minute ECG differs by age, ethnicity, and sex and is associated with hypertension, heart disease, faster sinus rates, electrolyte abnormalities, and lower educational attainment. Hypertension is likely to be a major cause of PVCs in adults.

Black or African American↗

PubMed2002

Correlates of the shift in heart rate variability with an active postural change in a healthy population sample: The Atherosclerosis Risk In Communities study.

BACKGROUND: The heart rate variability (HRV) response to postural change is a sensitive measure of the shift in autonomic balance from parasympathetic to sympathetic predominance that, when attenuated or absent, has been correlated with prevalent disease in patient populations. In a healthy population sample, we evaluated whether the shift in HRV with postural change differed by demographic characteristics as well as whether it differed between participants with established coronary heart disease (CHD) risk factors and their counterparts. METHODS: HRV was measured for 2 minutes in the supine and standing positions in a biracial sample of men and women (aged 45-64 years) without clinical CHD from the Atherosclerosis Risk In Communities Study (n = 7686). Mean differences among supine and standing mean R-R interval lengths, the SD of R-R intervals, and high-frequency power (HF) were compared by demographic characteristics (age, race, and sex) and CHD risk factors (smoking, obesity, physical activity, hypertension, and diabetes). Multivariable linear regression models were used to adjust for demographic characteristics. RESULTS: Smaller changes in R-R intervals and larger changes in SD of R-R intervals with standing were found among participants who were obese, less physically active than their counterparts, hypertensive, and diabetic. Smaller changes in HF were identified in male and white participants, but there were no differences in HF by CHD risk factors once models were adjusted for demographic characteristics. CONCLUSIONS: These simple noninvasive measures can be used to detect differences in cardiac autonomic balance that may be markers for autonomic impairment in healthy adults.

Age Factors↗

PubMed2002

Lower heart rate variability is associated with the development of coronary heart disease in individuals with diabetes: the atherosclerosis risk in communities (ARIC) study.

The objective of this study was to test prospectively in a population sample whether individuals with impaired heart rate variability (HRV) are at increased risk of developing coronary heart disease (CHD) and of non-CHD mortality and to test whether this relationship is more pronounced among individuals with diabetes. We examined the association between HRV and incident CHD and non-CHD mortality in a cohort of 11,654 men and women aged 45-64 years at intake, from the biracial, population-based Atherosclerosis Risk in Communities Study. Supine, resting, 2-min beat-to-beat heart rate data were collected at the baseline examination. High frequency (HF; 0.15-0.40 Hz) and low frequency (LF; 0.04-0.15 Hz) spectral powers, LF/HF ratio, normalized HF and LF, the standard deviation of all normal R-R intervals (SDNN), and the mean of the sum of the squared differences between adjacent normal R-R intervals (MSSD) were used as the conventional indexes of HRV to measure cardiac autonomic control. From this cohort, 635 cases of incident CHD (including 346 cases of incident myocardial infarction [MI] and 82 cases of fatal CHD), and 623 non-CHD deaths were identified and validated after an average of 8 years of follow-up. Among individuals with diabetes, the multivariable adjusted proportional hazards ratios (95% CI) were 2.03 (1.28-3.23), 1.60 (1.12-2.27), 1.50 (0.65-3.42), and 1.27 (0.84-1.91) for incident MI, incident CHD, fatal CHD, and non-CHD deaths, respectively, comparing the lowest quartile to the upper most three quartiles of HF. A similar pattern of associations was found for LF, SDNN, and MSSD. By contrast, there was no consistent pattern of associations among individuals without diabetes. At the population level, a lower HRV (reflective of impaired cardiac autonomic control) is statistically significantly related to the development of CHD among individuals with diabetes, independent of markers of the duration/severity of the glucose metabolism impairment. These data suggest a contribution of an impaired cardiac autonomic control to the risk of CHD among individuals with diabetes.

Autonomic Nervous System↗

PubMed2002

Vasectomy, inflammation, atherosclerosis and long-term followup for cardiovascular diseases: no associations in the atherosclerosis risk in communities study.

PURPOSE: Although human studies have failed to reveal an increased risk of clinical cardiovascular disease in men who undergo vasectomy, the possibility exists that an association may be detectable only after a long followup, or it may be more evident for subclinical than clinical disease. We assessed the association of vasectomy with inflammation and coagulation factors, carotid intimal-medial thickness, carotid plaque, prevalent peripheral arterial disease, and incident coronary heart disease and stroke in the Atherosclerosis Risk in Communities cohort. MATERIALS AND METHODS: Included in the study were 3,957 white men 45 to 64 years old who were free of coronary heart disease at the Atherosclerosis Risk in Communities (ARIC) baseline examination in 1987 to 1989. Data on vasectomy was collected at baseline by self-reporting. High resolution B-mode ultrasound was done to assess carotid intimal-medial thickness and carotid plaque. The cohort was followed an average of 9 years for incident cardiovascular events. RESULTS: Average time since vasectomy was 16 years. Approximately 20% of the population had undergone vasectomy 20 years or more ago at baseline. Multivariate analysis showed no association of vasectomy status with inflammation or coagulation factors, peripheral arterial disease, carotid plaque, carotid far wall thickness, incident coronary heart disease or stroke. Associations were unaffected by the time since vasectomy. CONCLUSIONS: There is no evidence in this population based sample of men indicating that vasectomy is related to atherosclerosis even after more than 20 years of followup.

Adult↗

PubMedDate not supplied

Risk factors for coronary heart disease in African Americans: the atherosclerosis risk in communities study, 1987-1997.

BACKGROUND: As part of the Atherosclerosis Risk in Communities Study, the race-specific incidence rates and risk factor prediction for coronary heart disease (CHD) were determined for black and white persons over 7 to 10 years of follow-up, from 1987 to 1997. METHODS: The sample included 14 062 men and women (2298 black women, 5686 white women, 1396 black men, and 4682 white men) aged 45 to 64 years who were free of clinical CHD at baseline. RESULTS: Average age-adjusted incidence rates (95% confidence intervals) for CHD per 1000 person-years were as follows: black women, 5.1 (4.2-6.2); white women, 4.0 (3.5-4.6); black men, 10.6 (8.9-12.7); and white men, 12.5 (11.5-13.7). Incidence rates (95% confidence intervals) using a definition for CHD that excluded revascularization procedures were as follows: black women, 4.9 (4.6-6.0); white women, 2.9 (2.5-3.4); black men, 9.2 (7.6-11.1); and white men, 7.9 (7.0-8.8). In a multivariable analysis, hypertension was a particularly strong risk factor in black women, with hazard rate ratios (95% confidence intervals) as follows: black women, 4.8 (2.5-9.0); white women, 2.1 (1.6-2.9); black men, 2.0 (1.3-3.0); and white men, 1.6 (1.3-1.9). Diabetes mellitus was somewhat more predictive in white women than in other groups. Hazard rate ratios (95% confidence intervals) were as follows: black women, 1.8 (1.2-2.8); white women, 3.3 (2.4-4.6); black men, 1.6 (1.1-2.5); and white men, 2.0 (1.6-2.6). Low-density lipoprotein cholesterol level was similarly predictive in all race-sex groups (hazard rate ratio, 1.2-1.4 per SD increment of low-density lipoprotein cholesterol level). High-density lipoprotein cholesterol level seemed somewhat more protective in white than in black persons. CONCLUSIONS: Findings from this study, along with clinical trial evidence showing efficacy, support aggressive management of traditional risk factors in black persons, as in white persons. Understanding the intriguing racial differences in risk factor prediction may be an important part of further elucidating the causes of CHD and may lead to better methods of preventing and treating CHD.

Age Distribution↗