Biomedical subjects

Sean A Coady

Publications and source records attributed to Sean A Coady.

4 recordsLinked to original sources

PubMed2005

Interactive effects between polymorphisms in the beta-adrenergic receptors and longitudinal changes in obesity.

We assessed interactions between polymorphisms in the beta-adrenergic receptor genes and longitudinal changes in obesity from childhood to adulthood using longitudinal data collected over a 24-year period from 1973 to 1996. Sex- and age-stratified analyses using random coefficients models were used to examine gene-gene interaction effects on obesity measures in 1179 African-American and white men and women (71% white, 57% women). Suggestive evidence for an interaction (p = 0.022) between the beta1- and beta2-adrenergic receptors was observed in men for longitudinal change in BMI. Men with Gly/Gly genotypes for both the beta1 and beta2 receptors showed significant increases (approximately 0.6%/yr) in BMI from childhood to adulthood. Women showed suggestive evidence for an interaction (p = 0.035) between the beta1- and beta3-adrenergic receptors for change over time in BMI. Women with Gly/Gly genotypes at the beta1-receptor and carrying at least one beta3-Arg allele showed notable increases in BMI. The regulation of lipolysis and development of obesity differ markedly between men and women and may be influenced by genetic polymorphisms, which contribute to the efficiency of the beta-adrenergic receptors, and hormonal effects on adrenergic receptor activity.

Black People↗

PubMed2004

Smoking and diabetes differ in their associations with subclinical atherosclerosis and coronary heart disease-the ARIC Study.

Atherosclerosis, nearly universally present in major arteries of Western adults, is characterized in all affected arteries by cholesterol-laden plaques and consistently associated with blood cholesterol levels. Other risk factors are reported to have relatively stronger or weaker associations with different atherosclerotic manifestations, but such differences have never previously been quantified. Measuring them may offer fresh clues to atherogenic processes and their prevention. The Atherosclerosis Risk in Communities Study (ARIC) ascertained incident coronary heart disease (CHD) and measured subclinical atherosclerosis as carotid artery intimal medial thickness using ultrasound and as lower extremity arterial disease (LEAD) using ankle-brachial blood pressure index. Blood cholesterol was associated with all endpoints. When standardized against LDL cholesterol associations, diabetes and smoking showed substantially different strengths of associations with different endpoints. Relative to associations with LDL cholesterol: (1) smoking, but not diabetes, increased in its strength of association with the severity of the underlying arterial disease; (2) the diabetes and smoking associations with CHD were much stronger in women than men, a phenomenon which, the standardization pattern suggests, is due to a gender difference in CHD pathogenesis, possibly attributable to arteriolar differences.

Ankle↗

PubMed2002

Genetic variability of adult body mass index: a longitudinal assessment in framingham families.

OBJECTIVE: To explore the contribution of genetics to the mean, SD, maximum value, maximum less the mean, and change over time in body mass index (BMI) and the residual of body weight after adjustment for height. BMI is frequently used as a general indicator of obesity because of its ease and reliability in ascertainment. Cross-sectional twin and family studies have shown a moderate-to-substantial genetic component for BMI. However, the contribution of genetics to the long-term average, variability, or change over time in BMI is less clear. RESEARCH METHODS AND PROCEDURES: Longitudinal data from the Framingham heart study were used to create pedigrees of age-matched individuals. Heritability estimates were derived using variance-decomposition methods on a total of 1051 individuals from 380 extended pedigrees followed for a period of 20 years. All subjects were followed from approximately age 35 to 55 years. RESULTS: Moderate heritability estimates were found for the mean BMI (h(2) = 0.37), maximum BMI (h(2) = 0.40), and the mean residual of body weight (h(2) = 0.36). Low heritability estimates (h(2) congruent with 0.20) were found for the maximum less the mean in BMI and the SDs of BMI and residual of body weight. No additive genetic contribution was found for the average change over time in BMI or the residual of body weight. DISCUSSION: These findings suggest that there is a significant genetic component for the magnitude of BMI throughout an individual's middle-adult years; however, little evidence was found for a genetic contribution to the variability or rate of change in an individual's BMI.

Adult↗

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↗