Obesity is a major risk factor for cardiovascular disease (CVD), with weight loss offering improvement in CVD risk factors.
To examine whether weight loss in laparoscopic adjustable gastric band (LAGB)-treated obese patients is associated with meaningful reductions in estimated 10- and 30- year Framingham CVD risk 12–15 months post-LAGB.
Obese adult patients [body mass index (BMI) ≥30 kg/m2] treated with LAGB were identified in a large US healthcare database. Patients without CVD at baseline and with measures of BMI, systolic blood pressure, diabetes, and smoking status at baseline and follow-up were eligible. Non-LAGB patients were propensity score matched to LAGB patients on baseline BMI, age, and gender. Estimated 10- and 30-year risk of developing CVD using office-based data, including BMI, was calculated at baseline and 12–15 months follow-up.
Mean BMI in LAGB patients (n = 647, average age 45.66 years, 81.1% female) decreased from 42.7 to 33.4 kg/m2 (P < 0.0001), with 35.4% no longer obese; 10- and 30-year estimated CVD risk decreased from 10.8 to 7.6% (P < 0.0001) and 44.34 to 32.30% (P < 0.0001), respectively, 12–15 months post-LAGB. Improvements were significantly greater than in non-LAGB patients (N = 4,295) (P < 0.0001). In the subset with lipid data (n = 74), improvements in total (−20.6 mg/dL; P < 0.05) and high-density lipoprotein (+10.6 mg/dL, P < 0.0001) cholesterol 1 year post-LAGB were also observed.
Data from a US healthcare database show that individuals undergoing LAGB have significant weight loss and reductions in estimated 10- to 30-year CVD risk within 1 year post-LAGB.
Cardiology; Cardiovascular disease; Framingham risk score; Laparoscopic adjustable gastric banding; Obesity; Weight loss
Coronary heart disease (CHD) is the major cause of death in the United States. Coronary artery calcification (CAC) scores are independent predictors of CHD. African Americans (AA) have higher rates of CHD but are less well-studied in genomic studies. We assembled the largest AA data resource currently available with measured CAC to identify associated genetic variants.
We analyzed log transformed CAC quantity (ln(CAC + 1)), for association with ~2.5 million single nucleotide polymorphisms (SNPs) and performed an inverse-variance weighted meta-analysis on results for 5,823 AA from 8 studies. Heritability was calculated using family studies. The most significant SNPs among AAs were evaluated in European Ancestry (EA) CAC data; conversely, the significance of published SNPs for CAC/CHD in EA was queried within our AA meta-analysis.
Heritability of CAC was lower in AA (~30%) than previously reported for EA (~50%). No SNP reached genome wide significance (p < 5E-08). Of 67 SNPs with p < 1E-05 in AA there was no evidence of association in EA CAC data. Four SNPs in regions previously implicated in CAC/CHD (at 9p21 and PHACTR1) in EA reached nominal significance for CAC in AA, with concordant direction. Among AA, rs16905644 (p = 4.08E-05) had the strongest association in the 9p21 region.
While we observed substantial heritability for CAC in AA, we failed to identify loci for CAC at genome-wide significant levels despite having adequate power to detect alleles with moderate to large effects. Although suggestive signals in AA were apparent at 9p21 and additional CAC and CAD EA loci, overall the data suggest that even larger samples and an ethnic specific focus will be required for GWAS discoveries for CAC in AA populations.
Atherosclerosis; Coronary artery calcium; Genetics; Meta-analysis; African-American
To examine the association of atherosclerosis burden in the survivors of an asymptomatic elderly cohort study and its relationship to other coronary risk factors (specifically, age) by evaluating aortic atherosclerotic wall burden by magnetic resonance imaging (MRI).
A total of 312 participants in an ongoing observational cohort study underwent cardiac and descending thoracic aorta imaging by MRI. Maximum wall thickness was measured and the mean wall thickness calculated. Wall/outer wall ratio was used as a normalized wall index (NWI) adjusted for artery size difference among participants. Percent wall volume (PWV) was calculated as NWI × 100.
In this asymptomatic cohort (mean age: 76 years), the mean (SD) aortic wall area and wall thickness were 222 ± 45 mm2 and 2.7 ± 0.4 mm, respectively. Maximum wall thickness was 3.4 ± 0.6 mm, and PWV was 32% ± 4%. Women appeared to have smaller wall area, but after correcting for their smaller artery size, had significantly higher PWV than men (P = 0.03). Older age was associated with larger wall area (P = 0.04 for trend) with similar PWVs. However, there were no statistically significant associations between standard risk factors, Framingham global risk, or metabolic syndrome status, therapy for cholesterol or hypertension, coronary or aortic calcium score, and the aortic wall burden. Aortic calcification was associated with coronary calcification.
Asymptomatic elderly in this cohort had a greater descending thoracic aortic wall volume that correlated with age, and women had a significantly increased PWV compared to men. In these survivors, the atherosclerotic aortic wall burden was not significantly associated with traditional risk factors or with coronary or aortic calcium scores or coronary calcium progression. Results suggest that age, or as yet unidentified risk factor(s), may be responsible for the increase in atherosclerosis.
Aging; Aortic atherosclerosis; Magnetic resonance imaging; Atherosclerotic risk factors
The purpose of the study was to examine and compare the incidence and progression of coronary artery calcium (CAC) among persons with metabolic syndrome (MetS) and diabetes mellitus (DM), compared to those with neither condition.
MetS and DM are associated with subclinical atherosclerosis as evidenced by coronary artery calcium (CAC).
The Multiethnic Study of Atherosclerosis included 6,814 African-American, Asian, Caucasian, and Hispanic adults aged 45–84 free of cardiovascular disease at baseline. 5,662 subjects (51% female, mean age 61.0 ± 10.3 years) received baseline and follow-up (mean 2.4 years) cardiac CT scans. We compared the incidence of CAC in 2,927 subjects without CAC at baseline and progression of CAC in 2,735 subjects with CAC at baseline in those with MetS without DM (25.2%), DM without MetS (3.5%), or both DM and MetS (9.0%), compared to neither MetS nor DM (58%). Progression of CAC was also examined in relation to coronary heart disease events over an additional 4.9 years.
Relative to those with neither MetS nor DM, adjusted relative risks (95% confidence intervals) for incident CAC were 1.7 (1.4–2.0), 1.9 (1.4–2.4), and 1.8 (1.4–2.2) (all p<0.01) and absolute differences in mean progression (volume score) were 7.8 (4.0–11.6; p<0.01), 11.6 (2.7–20.5; p<0.05), and 22.6 (17.2–27.9; p<0.01) for those with MetS without DM, DM without MetS, and both DM and MetS, respectively. Similar findings were seen in analysis using Agatston calcium score. In addition, progression predicted CHD events in those with MetS without DM (adjusted hazard ratio 4.1, 95% CI=2.0–8.5, p<0.01) and DM (4.9 [1.3–18.4], p<0.05) among those in highest tertile of CAC increase vs. no increase).
Individuals with MetS and DM have a greater incidence and absolute progression of CAC compared to individuals without these conditions, with progression also predicting CHD events in those with MetS and DM.
atherosclerosis; diabetes; risk factors; calcification
OBJECTIVE—Although metabolic syndrome is related to an increased risk of coronary heart disease (CHD) events, individuals with metabolic syndrome encompass a wide range of CHD risk levels. This study describes the distribution of 10-year CHD risk among U.S. adults with metabolic syndrome.
RESEARCH DESIGN AND METHODS—Metabolic syndrome was defined by the modified National Cholesterol Education Program (NCEP)/Third Adult Treatment Panel (ATP III) definition among 4,293 U.S. adults aged 20–79 years in the National Health and Nutrition Examination Survey 2003–2004. Low-, moderate-, moderately high–, and high-risk statuses were defined as <6, 6 to <10, 10–20, and >20% probability of CHD in 10 years (based on NCEP/ATP III Framingham risk score algorithms), respectively; those with diabetes or preexisting cardiovascular disease were assigned to high-risk status.
RESULTS—The weighted prevalence of metabolic syndrome by NCEP criteria in our study was 29.0% overall (30.0% in men and 27.9% in women, P = 0.28): 38.5% (30.7% men and 46.9% women) were classified as low risk, 8.5% (7.9% men and 9.1% women) were classified as moderate risk, 15.8% (23.4% men and 7.6% women) were classified as moderately high risk, and 37.3% (38.0% men and 36.5% women) were classified as high risk. The proportion at high risk increased with age but was similar among Hispanics, non-Hispanic whites, and non-Hispanic blacks.
CONCLUSIONS—Although many subjects with metabolic syndrome have a low calculated risk for CHD, about half have a moderately high or high risk, reinforcing the need for global risk assessment in individuals with metabolic syndrome to appropriately target intensity of treatment for underlying CHD risk factors.
While metabolic syndrome (MetS) and diabetes confer greater cardiovascular disease (CVD) risk, recent evidence suggests that individuals with these conditions have a wide range of risk. We evaluated whether screening for coronary artery calcium (CAC) and carotid intimal-medial thickness (CIMT) can improve CVD risk stratification over traditional risk factors (RFs) in people with MetS and diabetes.
RESEARCH DESIGN AND METHODS
We assessed CAC and CIMT in 6,603 people aged 45–84 years in the Multi-Ethnic Study of Atherosclerosis (MESA). Cox regression examined the association of CAC and CIMT with coronary heart disease (CHD) and CVD over 6.4 years in MetS and diabetes.
Of the subjects, 1,686 (25%) had MetS but no diabetes and 881 (13%) had diabetes. Annual CHD event rates were 1.0% among MetS and 1.5% for diabetes. Ethnicity and RF-adjusted hazard ratios for CHD for CAC 1–99 to ≥400 vs. 0 in subjects with neither MetS nor diabetes ranged from 2.6 to 9.5; in those with MetS, they ranged from 3.9 to 11.9; and in those with diabetes, they ranged from 2.9 to 6.2 (all P < 0.05 to P < 0.001). Findings were similar for CVD. CAC increased the C-statistic for events (P < 0.001) over RFs and CIMT in each group while CIMT added negligibly to prediction over RFs.
Individuals with MetS or diabetes have low risks for CHD when CAC or CIMT is not increased. Prediction of CHD and CVD events is improved by CAC more than by CIMT. Screening for CAC or CIMT can stratify risk in people with MetS and diabetes and support the latest recommendations regarding CAC screening in those with diabetes.
We hypothesized that insulin resistance, measured by the homeostatic model assessment of insulin resistance (HOMA), is independently associated with prevalent and incident extra-coronary calcification (ECC).
We studied calcium scores of the aortic valve (AVC), mitral valve (MVC), thoracic aorta (TAC) and aortic valve root (AVR) in 6,104 MESA participants not on diabetes medication who had baseline cardiac CT scans; 5,312 had follow-up scans (mean 2.4y). Relative-risk regression modeled prevalent and incident ECC adjusted for baseline demographics (model 1), and additionally for CVD risk factors (model 2).
In model 1, prevalence and incidence risk-ratios for the highest versus lowest quartile of HOMA were 20–30% higher in all ECC locations (p-value for trend ≤0.05 for all but incident-AVC). In model 2, all associations were attenuated, primarily by adjustment for metabolic syndrome components.
HOMA has a positive and graded association with ECC, but not independently of cardiovascular risk factors—particularly metabolic syndrome components.
cardiovascular calcification; insulin resistance; atherosclerosis; metabolic syndrome; computed tomography; valvular calcification; thoracic aortic calcification
We conducted a prospective randomized trial to compare the clinical impact of conventional risk factor modification to that associated with coronary artery calcium (CAC) scanning.
Although CAC scanning predicts cardiac events, its impact on subsequent medical management and CAD risk is not known.
We assigned 2,137 volunteers to groups that did versus did not undergo CAC scanning before risk factor counseling. The primary end-point was 4-year change in CAD risk factors and Framingham Risk Score (FRS). We also compared the groups for differences in downstream medical resource utilization.
Compared to the no-scan group, the scan group showed a net favorable change in systolic blood pressure (p=0.02), LDL-cholesterol (p=0.04), waist circumference for those with increased abdominal girth (p=0.01), and tendency to weight loss among overweight subjects (p=0.07). While mean FRS rose in the no-scan group, it remained static in the scan group (0.7±5.1 versus 0.002±4.9, p=0.003). Within the scan group, increasing baseline CAC score was associated with a dose-response improvement in systolic and diastolic blood pressure (p<0.001), total cholesterol (p<0.001), LDL-cholesterol (p<0.001), triglycerides (p<0.001), weight (p<0.001) and FRS (p=0.003). Downstream medical testing and costs in the scan group were comparable versus the no-scan group, balanced by lower and higher resource utilization for those with normal CAC scans and CAC scores ≥400, respectively.
As compared to no scanning, randomization to CAC scanning was associated with superior CAD risk factor control without increasing downstream medical testing. Further study of CAC scanning for improvement of cardiovascular outcomes may be warranted. (ClinicalTrials.gov, number NCT00927693).
coronary calcification; risk factors; coronary artery disease; prevention
To gain insight into early mechanisms of aortic widening, we examined associations between the diameter of the abdominal aorta (AD) and cardiovascular disease (CVD) risk factors and biomarkers, as well as measures of subclinical atherosclerosis, in a multi-ethnic population.
A total of 1926 participants (mean age 62, 50% women) underwent chest and abdomen scanning by computed tomography, ultrasound of the carotid arteries, and CVD risk factor assessment. AD was measured 5 cm above and at the bifurcation.
In a model containing traditional CVD risk factors, biomarkers and ethnicity, only age (standardized β=0.97), male sex (β=1.88), body surface area (standardized β=0.92), current smoking (β=0.42), D-dimer levels (β=0.19) and hypertension (β=0.53) were independently and significantly associated with increasing AD (in mm) at the bifurcation; use of cholesterol-lowering medications predicted smaller AD (β=-0.70) (P<.01 for all). These findings were similar for AD 5 cm above the bifurcation with one exception: compared to Caucasian-Americans, Americans of Chinese, African and Hispanic descent had significantly smaller AD 5 cm above the bifurcation (β's= -0.59, -0.49, and -0.52, respectively, all P<.01), whereas AD at the bifurcation did not differ by ethnicity. Physical activity, alcohol consumption, diabetes and levels of IL-6, CRP and homocysteine were not independently associated with AD. Higher aortic and coronary artery calcium burden, but not common carotid artery intima-media thickness, were independently, but modestly (β=0.11 to 0.19), associated with larger AD.
Incremental widening of the aortic diameter shared some, but not all, risk factors for occlusive vascular disease.
aorta; aneurysm; atherosclerosis; ethnicity; epidemiology
The initiation and acceleration of atherosclerosis is hypothesized as a physiologic mechanism underlying associations between air pollution and cardiovascular effects. Despite toxicologic evidence, epidemiologic data are limited.
In this cross-sectional analysis we investigated exposure to fine particulate matter (PM2.5) and residential proximity to major roads in relation to abdominal aortic calcification a sensitive indicator of systemic atherosclerosis. Aortic calcification was measured by computed tomography among 1147 persons, in 5 U.S. metropolitan areas, enrolled in the Multi-Ethnic Study of Atherosclerosis (MESA). The presence and quantity of aortic calcification were modeled using relative risk regression and linear regression, respectively, with adjustment for potential confounders.
We observed a slightly elevated risk of aortic calcification (RR = 1.06; 95% confidence interval = 0.96–1.16) with a 10-μg/m3 contrast in PM2.5. The PM2.5-associated risk of aortic calcification was stronger among participants with long-term residence near a PM2.5 monitor (RR = 1.11; 1.00–1.24) and among participants not recently employed outside the home (RR = 1.10; 1.00–1.22). PM2.5 was not associated with an increase in the quantity of aortic calcification (Agatston score) and no roadway proximity effects were noted. There was indication of PM2.5 effect modification by lipid-lowering medication use, with greater effects among users, and PM2.5 associations were observed most consistently among Hispanics.
Although we did not find persuasive associations across our full study population, associations were stronger among participants with less exposure misclassification. These findings support the hypothesis of a relationship between particulate air pollution and systemic atherosclerosis.
Abdominal aortic calcification (AAC) is a measure of subclinical cardiovascular disease (CVD). Data are limited regarding its relation to other measures of atherosclerosis.
Among 1,812 subjects (49% female, 21% black, 14% Chinese, and 25% Hispanic) within the population-based Multiethnic Study of Atherosclerosis, we examined the cross-sectional relation of AAC with coronary artery calcium (CAC), ankle brachial index (ABI), and carotid intimal medial thickness (CIMT), as well as multiple measures of subclinical CVD.
AAC prevalence ranged from 34% in those aged 45–54 to 94% in those aged 75–84 (p<0.0001), was highest in Caucasians (79%) and lowest in blacks (62%) (p<0.0001). CAC prevalence, mean maximum CIMT ≥ 1 mm, and ABI<0.9 was greater in those with vs. without AAC: CAC 60% vs 16%, CIMT 38% vs 7%, and ABI 5% vs 1% for women and CAC 80% vs 37%, CIMT 43% vs 16%, and ABI 4% vs 2% for men (p<0.01 for all except p<0.05 for ABI in men). The presence of multi-site atherosclerosis (≥ 3 of the above) ranged from 20% in women and 30% in men (p<0.001), was highest in Caucasians (28%) and lowest in Chinese (16%) and ranged from 5% in those aged 45–54 to 53% in those aged 75–84 (p<0.01 to p<0.001). Finally, increased AAC was associated with 2 to 3-fold relative risks for the presence of increased CIMT, low ABI, or CAC.
AAC is associated with an increased likelihood of other vascular atherosclerosis. Its additive prognostic value to these other measures is of further interest.
atherosclerosis; calcification; cardiovascular disease; epidemiology
The incidence of coronary heart disease (CHD) is higher in Northern than that in Southern China, however differences in traditional CHD risk factors do not fully explain this. No study has examined the differences in subclinical atherosclerosis that may help explain the differences in incidence. This study examined these differences in subclinical atherosclerosis using coronary computed tomography (CT) for calcification between the Northern and Southern China.
We selected a random sample of participants in a large multi-center ongoing epidemiologic study for coronary calcium scanning in one northern city (North) (Beijing, n = 49) and in two southern cities (South) (Shanghai, n = 50, and Guangzhou, n = 50). Participants from the three field centers (mean age 67 years) underwent coronary risk factor evaluation and cardiac CT scanning for coronary calcium measurement using the Multi-Ethnic Study of Atherosclerosis scanning protocol.
Adjusted log-transformed coronary artery calcium score in North China (Beijing) was 3.1 ± 0.4 and in South China (Shanghai and Guangzhou) was 2.2 ± 0.3 (P = 0.04). Mean calcium score for the northern city of Beijing was three times higher than that of the southern city of Guangzhou (P = 0.01) and 2.5 times higher than for the southern city of Shanghai (P = 0.03).
The extent of subclinical atherosclerosis is significantly higher in the northern city of Beijing than that in the two southern cities of Guangzhou and Shanghai, even after adjusting for standard cardiac risk factors. This finding suggests that standard risk factors do not fully explain north south differences in clinical CHD incidence.
coronary calcium; CT scanning; atherosclerosis; epidemiology; China
Among adults in the United States, the prevalence of reduced lung function including obstructive and restrictive lung disease is about 20%, representing an over 40 million adults. Persons with reduced lung function often demonstrate chronic systemic inflammation, such as from elevated levels of C-reactive protein. Substantial data suggests that inflammation may have a significant role in the association between reduced lung function and cardiovascular disease (CVD); however, how reduced lung function predicts CVD as risk modification remains largely unknown. Poor lung function has been shown to be a better predictor of all-cause and cardiac-specific mortality than established risk factors such as serum cholesterol, and CVD is the leading cause of mortality among those with impaired lung function. The exact mechanism of atherosclerosis is not clear, but persistent low grade inflammation is considered as one of the culprits in clot formation. The initial presentation of coronary heart disease is either myocardial infarction or sudden death in approximately half of the individuals. Unfortunately, conventional risk factor assessment predicts only 65-80% of future cardiovascular events, leaving many middle-aged and older individuals to manifest a major cardiovascular event despite being classified low risk by the Framingham risk estimates.
Respiratory function test
Pericardial fat is emerging as an important parameter for cardiovascular risk stratification. We extended previously developed quantitation of thoracic fat volume (TFV) from non-contrast coronary calcium (CC) CT scans to also quantify pericardial fat volume (PFV) and investigated the associations of PFV and TFV with CC and the Metabolic Syndrome (METS).
TFV is quantified automatically from user-defined range of CT slices covering the heart. Pericardial fat contours are generated by spline interpolation between 5-7 control points, placed manually on the pericardium within this cardiac range. Contiguous fat voxels within the pericardium are identified as pericardial fat. PFV and TFV were measured from non-contrast CT for 201 patients. In 105 patients, abdominal visceral fat area (VFA) was measured from an additional single-slice CT. In 26 patients, images were quantified by 2 readers to establish inter-observer variability. TFV and PFV were examined in relation to Body Mass Index (BMI), waist circumference and VFA, standard coronary risk factors (RF), CC (Agatston score >0) and METS.
PFV and TFV showed excellent correlation with VFA (R=0.79, R=0.89, p <0.0001), and moderate correlation with BMI (R=0.49, R=0.48, p<0.0001). In 26 scans, the inter-observer variability was greater for PFV (8.0 ± 5.3 %) than for TFV (4.4 ± 3.9 %, p = 0.001). PFV and TFV, but not RF, were associated with CC [PFV: p=0.04, Odds Ratio 3.1; TFV: p<0.001, OR 7.9]. PFV and TFV were also associated with METS [PFV: p<0.001, OR 6.1; TFV p<0.001, OR 5.7], unlike CC [OR=1.0 p =NS] or RF. PFV correlated with low-HDL and high-glucose; TFV correlated with low-HDL, low-adiponectin, and high glucose and triglyceride levels.
PFV and TFV can be obtained easily and reproducibly from routine CC scoring scans, and may be important for risk stratification and monitoring.
Pericardial fat; Thoracic fat; non-contrast CT; coronary calcium; metabolic syndrome
The utility of single versus combined blood pressure (BP) components in predicting cardiovascular disease (CVD) events is not established. We compared systolic BP (SBP) and diastolic BP (DBP) versus pulse pressure (PP) and mean arterial pressure (MAP) combined, and each of these four BP components alone in predicting CVD events.
Methods and Results
In participants in the original (n=4,760) and offspring (n=4,897) Framingham Heart Study who were free of CVD events and BP-lowering therapy, 1,439 CVD events occurred over serial 4-year intervals from 1952 to 2001. In pooled logistic regression using BP categories, combining SBP with DBP and PP with MAP improved model fit as compared to individual BP components (p<0.05 to p<0.0001). Significant interactions were noted between SBP and DBP (p=0.02) and between PP and MAP (p=0.01) in their respective multivariable models. Models with continuous variables for SBP + DBP and PP + MAP proved identical in predicting CVD events (AIC=10625 for both). Addition of a quadratic DBP2 term to DBP and SBP further improved fit (p=0.0016).
Combining PP with MAP and SBP with DBP produced models that were superior to single BP components for predicting CVD and the extent of CVD risk varied with the level of each BP component. PP + MAP (unlike SBP + DBP) have a monotonic relation with risk and may provide greater insight into hemodynamics of altered arterial stiffness vs. impaired peripheral resistance, but is not superior to SBP + DBP in predicting CVD events.
pulse pressure; mean arterial pressure; blood pressure; hypertension; cardiovascular diseases
We investigated the prevalence and risk factors of prehypertension, as well as the predictors of progression from prehypertension to hypertension. To do this, we performed a systematic review and meta-analysis of cross-sectional and longitudinal studies, after unrestricted searches of PubMed and The Cochrane Library through September 2010. In addition, we reviewed references, major textbooks, and review articles. Pooled prevalence, standardized mean differences, and odds ratios were estimated by using a random-effects model.
Twenty-six articles met our inclusion criteria; these included 20 cross-sectional and 6 longitudinal studies, with a total sample of 250,741 individuals. The overall pooled prevalence of prehypertension was 36%. The pooled prevalence among males was higher than that among females (40% vs 33%). The pooled standardized mean difference for body mass index was 1.37 (95% confidence interval [CI], 1.20–1.55); for total cholesterol, 8.08 (95% CI, 6.71–9.46); for low-density-lipoprotein cholesterol, 5.14 (95% CI, 3.09–7.18); and for fasting plasma glucose, 4.23 (95% CI, 3.28–5.18); all of which showed more significant results in females. The pooled odds ratio was 1.13 (95% CI, 0.93–1.37) for smoking and 0.98 (95% CI, 0.69–1.39) for drinking. In addition, factors such as older age at baseline, male sex, Mongolian race, and being overweight or obese were predictors of progression to hypertension, according to descriptive analysis.
The prevalence of prehypertension was relatively high, especially for males. There were many modifiable risk factors associated with prehypertension, to which healthcare providers should pay more attention.
Adult; blood glucose/analysis; blood pressure; body mass index; cholesterol, HDL/blood; cholesterol, LDL/blood; cross-sectional studies; disease susceptibility; hypertension/diagnosis/epidemiology/etiology/prevention & control; longitudinal studies; meta-analysis; obesity; prehypertension/epidemiology/etiology/prevention & control; prevalence; risk factors; triglycerides/blood; waist circumference
While asymptomatic patients should have a lower risk of cardiac events compared to symptomatic patients referred for cardiac stress testing, comparable event rates have been noted in some prior prognostic studies. To test if a high burden of undetected atherosclerosis among asymptomatic patients helps explain such findings, we compared atherosclerotic burden, as measured by coronary artery calcium (CAC) scanning, in propensity-matched groups of volunteers and asymptomatic patients.
CAC scans were performed on a research basis in 136 asymptomatic patients referred for exercise myocardial perfusion SPECT and in 1,398 volunteers. We performed matching by propensity scores to compare volunteers with the same CAD risk factor profile as our asymptomatic patients.
Among our matched groups, asymptomatic patients had significantly greater mean CAC scores than volunteers (394 ± 805 vs 151 ± 349, P = .001), primarily due to a higher frequency of CAC scores >1,000 (15.4% vs 2.5%, P < .001). Inducible myocardial ischemia by SPECT was present in 7% of patients, but was selectively concentrated among those with CAC scores >1,000, occurring in 27.0% of such patients vs only 1.9% among patients with CAC scores <1,000 (P < .0001).
In contrast to asymptomatic volunteers, asymptomatic patients referred for cardiac stress testing possess more extensive atherosclerosis as measured by CAC. Among asymptomatic patients with high CAC scores, the frequency of concomitant inducible myocardial ischemia is high. These results help explain prior prognostic studies concerning asymptomatic patients and indicate the importance of making a clinical distinction between healthy subjects and asymptomatic patients with respect to atherosclerotic risk.
Coronary calcification; ischemia; atherosclerosis; coronary artery disease
Asian subgroup-specific information on type 2 diabetes mellitus (DM) is scarce. Using the California Health Interview Survey 2007 data, we examined Chinese, Korean, Japanese, Filipinos, and Vietnamese adults (n = 3,688) and Caucasian adults (n = 33,981) for the prevalence of DM and risk factors. The age-adjusted prevalence of DM was the highest among Filipinos (8.05%) followed by Japanese (7.07%), Vietnamese (7.03%), and Koreans (6.3%). Chinese (5.93%) was the only Asian group studied whose prevalence was lower than Caucasians (5.94%). From multiple logistic regression, after adjusting for risk factors, Japanese had the highest likelihood of DM (OR = 1.75, CI = [1.12–2.73], P < 0.05), followed by Filipinos (1.66, [1.13–2.43], P < 0.01), and Koreans (1.59, [1.00–2.52], P < 0.05), relative to Caucasians. Our results suggest that even after accounting for lifestyle and other risk factor differences between Caucasians and key Asian subgroups in California, Japanese, Filipinos, and Koreans have a 1.6–1.75 greater likelihood of DM compared to Caucasians.
Asians; Type 2 diabetes; Surveys; Epidemiology
Pericardial fat volume (PFV) and thoracic fat volume (TFV) can be routinely measured from noncontrast CT (NCT) performed for calculating coronary calcium score (CCS) and may predict major adverse cardiovascular event (MACE) risk.
From a registry of 2751 asymptomatic patients without known CAD and 4-year follow-up for MACE (cardiac death, myocardial infarction, stroke, late revascularization) after NCT, we compared 58 patients with MACE (“EVENTS”) to 174 same-sex event-free controls matched by a propensity score to account for age, risk factors, and CCS. TFV was automatically calculated, and PFV was calculated with manual assistance in defining the pericardial contour, within which fat voxels were automatically identified. Independent relationships of PFV and TFV to MACE were evaluated using conditional multivariable logistic regression.
EVENTS had higher mean PFV (101.8±49.2 cm3 vs. 84.9±37.7 cm3, p=0.007) and TFV (204.7±90.3 cm3 vs. 177±80.3 cm3, p=0.029) and higher frequencies of PFV>125 cm3 (33% vs. 14%, p=0.002) and TFV>250 cm3 (31% vs. 17%, p=0.025). After adjusting for Framingham Risk Score, CCS, and body-mass-index, PFV and TFV were significantly associated with MACE (odds ratio (OR) 1.74, 95%CI 1.03–2.95 for each doubling of PFV; OR 1.78, 95%CI 1.01–3.14 for TFV). Areas-under-the-curve from receiver operating characteristic analyses showed a trend of improved MACE prediction when PFV was added to FRS and CCS (0.73 vs 0.68, p=0.058). Addition of PFV, but not TFV, to FRS and CCS improved estimated specificity (0.72 vs 0.66, p=0.008) and overall accuracy (0.70 vs 0.65, p=0.009) in predicting MACE.
Asymptomatic patients who experience MACE exhibit greater PFV on pre-MACE NCT when compared to event-free controls with similar cardiovascular risk profiles. Our preliminary findings suggest that PFV may help improve prediction of MACE.
Pericardial fat; computed tomography; prognosis; cardiovascular events
The aims of this study were to 1) determine the association between ethnicity and both thoracic and abdominal aortic calcium (TAC and AAC) and 2) investigate associations between cardiovascular disease (CVD) risk factors and both TAC and AAC. Participants were 1,957 men and women enrolled in the Multi-Ethnic Study of Atherosclerosis who had computed tomography scans of both the chest and abdomen. These scans were obtained at the same clinic visit and calcium scores were computed using the Agatston method. Regression analyses were conducted using relative risk regression. The mean age was 65 years and 50% were female. Forty % were White, 26% Hispanic, 21% African American and 13% Chinese. Whites had the highest prevalence of AAC (80%), which was significantly higher than Hispanics (68%, p<0.001), African Americans (63%, p<0.001) and Chinese (74%, p=0.029). Similarly, Whites had the highest prevalence of TAC (42%), which was significantly higher than Hispanics (30%, p < 0.01) and African Americans (27%, p<0.001) but was not significantly different from that in Chinese (38%). Compared to Whites and after adjustment for age, sex, body mass index, hypertension, diabetes, dyslipidemia, smoking and family history of CVD, Hispanics and African Americans, but not Chinese Americans, had a significantly lower risk for the presence of any AAC or any TAC. In these models, diabetes, smoking and dyslipidemia had stronger associations with AAC while hypertension was stronger for TAC. In conclusion, compared to Whites, African-Americans and Hispanics, but not Chinese, have evidence of less atherosclerosis in both the thoracic and abdominal aorta which does not appear to be accounted for by traditional CVD risk factors.
European treatment guidelines in persons with known coronary heart disease (CHD) focus on adherence to antiplatelet therapy, β-blockers, ACE/ARBs, and lipid-lowering agents, with goals for blood pressure (BP) of < 140/90 mm Hg and LDL cholesterol of < 3.0 mmol/l. Data on adherence to these measures in Eastern Europe are limited.
Material and methods
The Third Republic of Srpska, Bosnia and Herzegovina, Coronary Prevention Study (ROSCOPS III) was conducted in 2005–2006 at 10 primary heath care centres in 601 patients (36% female, mean age 55 years) with CHD including acute myocardial infarction or ischaemia, coronary artery bypass graft, or angioplasty who were examined and interviewed at least 6 months after the event. We examined the proportion of subjects on recommended treatments and at goal for BP, LDL-C, and non-smoking.
The proportion of subjects on recommended treatments included 61% for β-blockers, 79% for ACE/ARBs, 63% for lipid-lowering agents and 74% for antiplatelet therapy. Only 30% of subjects were on all four of these treatments. 59% of subjects had BP at goal of < 140/90 mm Hg and 33% were controlled to < 130/80 mm Hg, 41% for LDL-C, and 88% were non-smokers. Improvements were seen in lipid-lowering and ACE/ARB drug use and non-smoking status from an earlier survey (ROSCOPS II) in 2002–2003.
Our data show, despite improvement over recent years, that many persons with CHD in the Republic of Srpska, Bosnia and Herzegovina are neither on recommended treatments nor at target for BP and/or LDL-C. Improved efforts targeted at both physicians and patients to address these issues are needed.
treatment; risk factors; coronary heart disease; secondary prevention
Metabolic syndrome (MetS) has been associated with increased prevalence of aortic valve calcium (AVC) and with increased progression of aortic stenosis. The purpose of this study was to determine whether MetS is associated with increased risks for the development of new (“incident”) AVC or for progression of established AVC as assessed by CT.
RESEARCH DESIGN AND METHODS
The relationships of MetS or its components as well as of diabetes to risks for incident AVC or AVC progression were studied among participants with CT scans performed at baseline and at either year 2 or year 3 examinations in the Multi-Ethnic Study of Atherosclerosis (MESA).
Of 5,723 MESA participants meeting criteria for inclusion, 1,674 had MetS by Adult Treatment Panel III criteria, whereas 761 had diabetes. Among the 5,123 participants without baseline AVC, risks for incident AVC, adjusted for time between scans, age, sex, race/ethnicity, LDL cholesterol, lipid-lowering medications, and smoking, were increased significantly for MetS (odds ratio [OR] 1.67 [95% CI 1.21–2.31]) or diabetes (2.06 [1.39–3.06]). In addition, there was an increase in incident AVC risk with increasing number of MetS components. Similar results were found using the International Diabetes Federation MetS criteria. Among the 600 participants (10.5%) with baseline AVC, neither MetS nor diabetes was associated with AVC progression.
In the MESA cohort, MetS was associated with a significant increase in incident (“new”) AVC, raising the possibility that MetS may be a potential therapeutic target to prevent AVC development.
Despite compelling evidence that aspirin reduces fatal and non-fatal vascular events among the overall population in various settings, women have frequently been underrepresented and their data underreported. We sought to evaluate the relationship between aspirin use, dose (81 or 325mg) and clinical outcomes among postmenopausal women with stable cardiovascular disease.
Women with cardiovascular disease (n=8928) enrolled in the Women’s Health Initiative Observational Study were used for this analysis. The primary outcome was the incidence of all-cause mortality and cardiovascular events (myocardial infarction, stroke and cardiovascular death).
Among 8928 women with stable cardiovascular disease, 4101 (46%) reported taking aspirin, of whom 30% were on 81 and 70% were on 325mg. At 6.5 years of follow-up, no significant association was noted for aspirin use and all-cause mortality or cardiovascular events. However, after multivariate adjustment, aspirin use was associated with a significantly lower all-cause (adjusted HR 0.86, [0.75-0.99], P=0.04) and cardiovascular related mortality (adjusted HR 0.75, [0.60-0.95], P=0.01) compared with no aspirin. Aspirin use was associated with a lower risk of cardiovascular events (adjusted HR 0.90, [0.78-1.04], P=0.14) which did not meet statistical significance. Compared with 325mg, use of 81mg was not significantly different for all-cause mortality, cardiovascular events or any individual endpoint.
After multivariate adjustment, aspirin use was associated with significantly lower risk of all-cause mortality, specifically cardiovascular mortality, among postmenopausal women with stable cardiovascular disease. No significant difference was noted between 81 and 325mg of aspirin. Overall, aspirin use was low in this cohort of women with stable cardiovascular disease.
Aspirin; Dose; Women; Cardiovascular Disease; Observational Study
OBJECTIVE—A relationship between inflammation, measured by C-reactive protein (CRP), and forced vital capacity (FVC) in diabetes or metabolic syndrome (MetS) has not been established. We investigated whether high CRP is related to reduced FVC in MetS and diabetes.
RESEARCH DESIGN AND METHODS—We examined the association of MetS/diabetes and CRP (normal ≤3 mg/l, high >3 mg/l) with predicted FVC in 4,272 nonsmoking U.S. adults aged 18–79 years without lung disease in the Third National Health and Nutrition Examination Survey. Logistic regression examined odds of FVC <80% by CRP and MetS/diabetes.
RESULTS—Mean FVC in individuals with MetS and high CRP (95.7%) and those with diabetes and high CRP (93.7%) was lower than in those with no MetS/diabetes and normal CRP (101.7%) (P < 0.01) and was lower in those with MetS and high CRP (95.7%) than in those with MetS and normal CRP (98.5%) (P < 0.01). The odds ratio (95% CI) of FVC <80% was highest in individuals with MetS and high CRP (odds ratio 4.26 [95% CI 2.08–8.73], P < 0.01) compared with those with no MetS/diabetes and normal CRP.
CONCLUSIONS—Elevated CRP is associated with lower FVC in people with MetS.