High prevalence of subclinical atherosclerosis by carotid ultrasound among Mexican Americans: discordance with 10-year risk assessment using the Framingham risk score

ackground: Framingham risk scores (FRS) were validated in a mostly Caucasian population. Evaluation of subclinical atherosclerosis by carotid ultrasound may improve ascertainment of risk in nonwhite populations. This study aimed to evaluate carotid intima-media thickness (cIMT) and carotid plaquing among Mexican Americans, and to correlate these markers with coronary risk factors and the FRS. Methods/results: Participants (n = 141) were drawn from the Cameron County Hispanic Cohort. Carotid artery ultrasound was performed and cIMT measured. Carotid plaque was defined as areas of thickening \u3e50% of the thickness of the surrounding walls. Mean age was 53.1 ± 11.7 years (73.8% female). Most were overweight or obese (88.7%) and more than half (53.2%) had the metabolic syndrome. One third (34.8%) had abnormal carotid ultrasound findings (either cIMT ≥75th percentile for gender and age or presence of plaque). Among those with abnormal carotid ultrasound, the majority were classified as being at low 10-year risk for cardiovascular events. Carotid ultrasound reclassified nearly a third of the cohort as being at high risk. This discordance between 10-year FRS and carotid ultrasound was noted whether risk was assessed for hard coronary events or global risk. Concordance between FRS and carotid ultrasound findings was best when long-term (30-year) risk was assessed and no subject with an abnormal carotid ultrasound was categorized as low risk by the 30-year FRS algorithm. Conclusions: Integration of carotid ultrasound findings to coronary risk assessments and use of longer term prediction models may provide better risk assessment in this minority population, with earlier initiation of appropriate therapies

Association of Visceral Adipose Tissue and Subclinical Atherosclerosis in US-Born Mexican Americans but not First Generation Immigrants

BACKGROUND: Excess visceral adipose tissue (VAT) is a primary driver for the cardiometabolic complications of obesity; VATassociated cardiovascular disease risk varies by race, but most studies have been done on Non-Hispanics. This study aimed to evaluate the clinical and metabolic correlates of VAT, its association with subclinical atherosclerosis, and the factors affecting this association in Mexican Americans. METHODS AND RESULTS: Participants (n=527) were drawn from the Cameron County Hispanic Cohort (CCHC), on whom a carotid ultrasound to assess carotid intima media thickness and a dual-energy X-ray absorptiometry scan to assess for VAT were obtained. Those in the highest quartiles of VAT were more likely to have hypertension, hypertriglyceridemia, low high-density lipoprotein, diabetes mellitus, and metabolic syndrome. Increased carotid intima media thickness was more prevalent in those in the highest quartile for VAT (57.4% versus 15.4% for the lowest quartile; P\u3c0.001). There was a graded increase in mean carotid intima media thickness with increasing VAT, after adjusting for covariates; for every 10 cm2 increase in VAT, there was an increase of 0.004 mm (SE=0.002; P=0.0299) in mean carotid intima media thickness. However, this association was only seen among second or higher generation US-born Mexican Americans but not among first generation immigrants (P=0.024). CONCLUSIONS: Excess VAT is associated with indicators of metabolic disorders and subclinical atherosclerosis in Mexican Americans regardless of body mass index. However, acculturation appears to be an important modulator of this association. Longitudinal follow-up with targeted interventions among second or higher generation Hispanics to lower VAT and improve cardiometabolic risk may help prevent premature cardiovascular disease in this cohort

Subclinical Atherosclerosis and Obesity Phenotypes Among Mexican Americans

Background Data on the influence of obesity on atherosclerosis in Hispanics are inconsistent, possibly related to varying cardiometabolic risk among obese individuals. We aimed to determine the association of obesity and cardiometabolic risk with subclinical atherosclerosis in Mexican‐Americans. Methods and Results Participants (n=503) were drawn from the Cameron County Hispanic Cohort. Metabolic health was defined as \u3c2 of the following: blood pressure ≥130/85; triglyceride ≥150 mg/dL; high‐density lipoprotein cholesterol \u3c40 mg/dL (men) or \u3c50 mg/dL (women); fasting glucose ≥100 mg/dL; homeostasis model assessment of insulin resistance value \u3e5.13; or high‐sensitivity C‐reactive protein \u3e3 mg/L. Carotid intima media thickness (cIMT) was measured. A high proportion of participants (77.8%) were metabolically unhealthy; they were more likely to be male, older, with fewer years of education, and less likely to meet daily recommendations regarding fruit and vegetable servings. One‐third (31.8%) had abnormal carotid ultrasound findings. After adjusting for covariates, mean cIMT varied across the obesity phenotypes (P=0.0001); there was no difference among the metabolically unhealthy regardless of whether they were obese or not. In multivariable analysis, after adjusting for covariates, cardiometabolic risk (P=0.0159), but not obesity (P=0.1446), was significantly associated with subclinical atherosclerosis. Conclusions In Mexican‐Americans, cardiometabolic risk has a greater effect on early atherosclerosis development than body mass index. Non‐obese but metabolically unhealthy participants had similar development of subclinical atherosclerosis as their obese counterparts. Interventions to maintain metabolic health among obese and non‐obese patients may be a more important goal than weight loss alone

Frequency of Nonalcoholic Fatty Liver Disease and Subclinical Atherosclerosis Among Young Mexican Americans

Non-alcoholic fatty liver disease (NAFLD) is considered the hepatic manifestation of the metabolic syndrome, whose criteria are risk factors for atherosclerotic cardiovascular disease. We aimed to evaluate the prevalence of NAFLD, its association with subclinical atherosclerosis, and factors that may account for this association in Mexican Americans. In a population based cross-sectional sample drawn from the Cameron County Hispanic Cohort in Texas, carotid intima media thickness (cIMT), an indicator of subclinical atherosclerosis, was measured. Abnormal carotid ultrasound study was defined as mean cIMT \u3e75th percentile for age and gender and/or plaque presence. NAFLD was defined as steatosis by ultrasound in absence of other causes of liver disease. Multivariable weighted regression analyses were performed to evaluate associations between NAFLD and cIMT. Mean age was 50.4±1.2 years with 58.3% females. Mean body mass index (BMI) was 31.0 ± 0.4 kg/m2, and 54.0% had the metabolic syndrome. NAFLD was highly prevalent (48.80%); subjects with NAFLD had greater BMI, central obesity, fasting glucose levels, and dyslipidemia, and were more likely to have the metabolic syndrome. Nearly one third of subjects with NAFLD also had evidence of subclinical atherosclerosis (31.2%). After adjusting for covariates, there was an independent association between NAFLD and increased cIMT only in younger subjects \u3c45 years (p=0.0328). Subjects with both abnormal liver and carotid ultrasound studies tended to be obese, diabetic, and have the metabolic syndrome. In conclusion, NAFLD is highly prevalent in this Mexican American cohort, with an independent association between NAFLD and subclinical atherosclerosis among younger subjects; clustering of diabetes, obesity, and metabolic syndrome in this health disparity cohort increases the risk of both liver disease and early atherosclerosis in young adults

The Evolution of the Stellar Hosts of Radio Galaxies

We present new near-infrared images of z>0.8 radio galaxies from the flux-limited 7C-III sample of radio sources for which we have recently obtained almost complete spectroscopic redshifts. The 7C objects have radio luminosities about 20 times fainter than 3C radio galaxies at a given redshift. The absolute magnitudes of the underlying host galaxies and their scale sizes are only weakly dependent on radio luminosity. Radio galaxy hosts at z~2 are significantly brighter than the hosts of radio-quiet quasars at similar redshifts and the model AGN hosts of Kauffmann & Haehnelt (2000). There is no evidence for strong evolution in scale size, which shows a large scatter at all redshifts. The hosts brighten significantly with redshift, consistent with the passive evolution of a stellar population that formed at z>~3. This scenario is consistent with studies of host galaxy morphology and submillimeter continuum emission, both of which show strong evolution at z>~2.5. The lack of a strong ``redshift cutoff'' in the radio luminosity function to z>4 suggests that the formation epoch of the radio galaxy host population lasts >~1Gyr from z>~5 to z~3. We suggest these facts are best explained by models in which the most massive galaxies and their associated AGN form early due to high baryon densities in the centres of their dark matter haloes.Comment: To appear in A

Missed opportunities for diagnosis and treatment of diabetes, hypertension, and hypercholesterolemia in a Mexican American population, Cameron County Hispanic Cohort, 2003-2008

Introduction Diabetes, hypertension, and hypercholesterolemia are common chronic diseases among Hispanics, a group projected to comprise 30% of the US population by 2050. Mexican Americans are the largest ethnically distinct subgroup among Hispanics. We assessed the prevalence of and risk factors for undiagnosed and untreated diabetes, hypertension, and hypercholesterolemia among Mexican Americans in Cameron County, Texas. Methods We analyzed cross-sectional baseline data collected from 2003 to 2008 in the Cameron County Hispanic Cohort, a randomly selected, community-recruited cohort of 2,000 Mexican American adults aged 18 or older, to assess prevalence of diabetes, hypertension, and hypercholesterolemia; to assess the extent to which these diseases had been previously diagnosed based on self-report; and to determine whether participants who self-reported having these diseases were receiving treatment. We also assessed social and economic factors associated with prevalence, diagnosis, and treatment. Results Approximately 70% of participants had 1 or more of the 3 chronic diseases studied. Of these, at least half had had 1 of these 3 diagnosed, and at least half of those who had had a disease diagnosed were not being treated. Having insurance coverage was positively associated with having the 3 diseases diagnosed and treated, as were higher income and education level. Conclusions Although having insurance coverage is associated with receiving treatment, important social and cultural barriers remain. Failure to provide widespread preventive medicine at the primary care level will have costly consequences

Electrocardiographic abnormalities among Mexican Americans: Correlations with diabetes, obesity, and the metabolic syndrome

Background: Resting ischemic electrocardiographic abnormalities have been associated with cardiovascular mortality. Simple markers of abnormal autonomic tone have also been associated with diabetes, obesity, and the metabolic syndrome in some populations. Data on these electrocardiographic abnormalities and correlations with coronary risk factors are lacking among Mexican Americans wherein these conditions are prevalent. Objective: This study aimed to evaluate the prevalent resting electrocardiographic abnormalities among community-dwelling Mexican Americans, and correlate these findings with coronary risk factors, particularly diabetes, obesity, and the metabolic syndrome. Methods: Study subjects (n=1280) were drawn from the Cameron County Hispanic Cohort comprised of community-dwelling Mexican Americans living in Brownsville, Texas at the United States-Mexico border. Ischemic electrocardiographic abnormalities were defined as presence of ST/T wave abnormalities suggestive of ischemia, abnormal Q waves, and left bundle branch block. Parameters that reflect autonomic tone, such as heart rate-corrected QT interval and resting heart rate, were also measured. Results: Ischemic electrocardiographic abnormalities were more prevalent among older persons and those with hypertension, diabetes, obesity, and the metabolic syndrome. Subjects in the highest quartiles of QTc interval and resting heart rate were also more likely to be diabetic, hypertensive, obese, or have the metabolic syndrome. Conclusions: Among Mexican Americans, persons with diabetes, obesity, and the metabolic syndrome were more likely to have ischemic electrocardiographic abnormalities, longer QTc intervals, and higher resting heart rates. A resting electrocardiogram can play a complementary role in the comprehensive evaluation of cardiovascular risk in this minority population

Progressive regression of left ventricular hypertrophy two years after bariatric surgery.

BACKGROUND: Obesity is a systemic disorder associated with an increase in left ventricular mass and premature death and disability from cardiovascular disease. Although bariatric surgery reverses many of the hormonal and hemodynamic derangements, the long-term collective effects on body composition and left ventricular mass have not been considered before. We hypothesized that the decrease in fat mass and lean mass after weight loss surgery is associated with a decrease in left ventricular mass. METHODS: Fifteen severely obese women (mean body mass index [BMI]: 46.7+/-1.7 kg/m(2)) with medically controlled hypertension underwent bariatric surgery. Left ventricular mass and plasma markers of systemic metabolism, together with body mass index (BMI), waist and hip circumferences, body composition (fat mass and lean mass), and resting energy expenditure were measured at 0, 3, 9, 12, and 24 months. RESULTS: Left ventricular mass continued to decrease linearly over the entire period of observation, while rates of weight loss, loss of lean mass, loss of fat mass, and resting energy expenditure all plateaued at 9 [corrected] months (P \u3c.001 for all). Parameters of systemic metabolism normalized by 9 months, and showed no further change at 24 months after surgery. CONCLUSIONS: Even though parameters of obesity, including BMI and body composition, plateau, the benefits of bariatric surgery on systemic metabolism and left ventricular mass are sustained. We propose that the progressive decrease of left ventricular mass after weight loss surgery is regulated by neurohumoral factors, and may contribute to improved long-term survival

Stabilizing Peri-Stent Restenosis Using a Novel Therapeutic Carrier

Late in-stent restenosis remains a significant problem. Bare-metal stents were implanted into peripheral arteries in miniature swine, followed by direct intra-arterial infusion of nitric oxide-loaded echogenic liposomes (ELIPs) and anti-intercellular adhesion molecule-1 conjugated ELIPs loaded with pioglitazone exposed to an endovascular catheter with an ultrasonic core. Ultrasound-facilitated delivery of ELIP formulations into stented peripheral arteries attenuated neointimal growth. Local atheroma-targeted, ultrasound-triggered delivery of nitric oxide and pioglitazone, an anti-inflammatory peroxisome proliferator-activated receptor-γ agonist, into stented arteries has the potential to stabilize stent-induced neointimal growth and obviate the need for long-term antiplatelet therapy

Socio-economic status and types of childhood injury in Alberta: a population based study

BACKGROUND: Childhood injury is the leading cause of mortality, morbidity and permanent disability in children in the developed world. This research examines relationships between socio-economic status (SES), demographics, and types of childhood injury in the province of Alberta, Canada. METHODS: Secondary analysis was performed using administrative health care data provided by Alberta Health and Wellness on all children, aged 0 to 17 years, who had injuries treated by a physician, either in a physician's office, outpatient department, emergency room and/or as a hospital inpatient, between April 1(st). 1995 to March 31(st). 1996. Thirteen types of childhood injury were assessed with respect to age, gender and urban/rural location using ICD9 codes, and were related to SES as determined by an individual level SES indicator, the payment status of the Alberta provincial health insurance plan. The relationships between gender, SES, rural/urban status and injury type were determined using logistic regression. RESULTS: Twenty-four percent of Alberta children had an injury treated by physician during the one year period. Peak injury rates occurred about ages 2 and 13–17 years. All injury types except poisoning were more common in males. Injuries were more frequent in urban Alberta and in urban children with lower SES (receiving health care premium assistance). Among the four most common types of injury (78.6% of the total), superficial wounds and open wounds were more common among children with lower SES, while fractures and dislocations/sprains/strains were more common among children receiving no premium assistance. CONCLUSION: These results show that childhood injury in Alberta is a major health concern especially among males, children living in urban centres, and those living on welfare or have Treaty status. Most types of injury were more frequent in children of lower SES. Analysis of the three types of the healthcare premium subsidy allowed a more comprehensive picture of childhood injury with children whose families are on welfare and those of Treaty status presenting more frequently for an injury-related physician's consultation than other children. This report also demonstrates that administrative health care data can be usefully employed to describe injury patterns in children