Obesity often clusters with other major cardiovascular disease risk factors, yet a subset of the obese appears to be protected from these risks. Two obesity phenotypes are described, 1) “metabolically healthy” obese, broadly defined as body mass index (BMI) ≥ 30 kg/m2 and favorable levels of blood pressure, lipids, and glucose; and 2) “at risk” obese, BMI ≥ 30 with unfavorable levels of these risk factors. More than 30% of obese American adults are metabolically healthy. Diet and activity determinants of obesity phenotypes are unclear. We hypothesized that metabolically healthy obese have more favorable behavioral factors, including less adverse diet composition and higher activity levels than at risk obese in the multi-ethnic group of 775 obese American adults ages 40–59 years from the International Population Study on Macro/Micronutrients and Blood Pressure (INTERMAP) cohort. In gender stratified analyses, mean values for diet composition and activity behavior variables, adjusted for age, race, and education, were compared between metabolically healthy and at risk obese. Nearly 1 in 5 (149/775, or 19%) of obese American INTERMAP participants were classified as metabolically healthy obese. Diet composition and most activity behaviors were similar between obesity phenotypes, although metabolically healthy obese women reported higher sleep duration than at risk obese women. These results do not support hypotheses that diet composition and/or physical activity account for the absence of cardiometabolic abnormalities in metabolically healthy obese.
Major cardiovascular diseases (CVDs) are leading causes of mortality among US Hispanic and Latino individuals. Comprehensive data are limited regarding the prevalence of CVD risk factors in this population and relations of these traits to socioeconomic status (SES) and acculturation.
To describe prevalence of major CVD risk factors and CVD (coronary heart disease [CHD] and stroke) among US Hispanic/Latino individuals of different backgrounds, examine relationships of SES and acculturation with CVD risk profiles and CVD, and assess cross-sectional associations of CVD risk factors with CVD.
Design, Setting, and Participants
Multicenter, prospective, population-based Hispanic Community Health Study/Study of Latinos including individuals of Cuban (n =2201), Dominican (n = 1400), Mexican (n=6232), Puerto Rican (n=2590), Central American (n=1634), and South American backgrounds (n = 1022) aged 18 to 74 years. Analyses involved 15 079 participants with complete data enrolled between March 2008 and June 2011.
Main Outcome Measures
Adverse CVD risk factors defined using national guidelines for hypercholesterolemia, hypertension, obesity, diabetes, and smoking. Prevalence of CHD and stroke were ascertained from self-reported data.
Age-standardized prevalence of CVD risk factors varied by Hispanic/Latino background; obesity and current smoking rates were highest among Puerto Rican participants (for men, 40.9% and 34.7%; for women, 51.4% and 31.7%, respectively); hypercholesterolemia prevalence was highest among Central American men (54.9%) and Puerto Rican women (41.0%). Large proportions of participants (80% of men, 71% of women) had at least 1 risk factor. Age- and sex-adjusted prevalence of 3 or more risk factors was highest in Puerto Rican participants (25.0%) and significantly higher (P<.001) among participants with less education (16.1%), those who were US-born (18.5%), those who had lived in the United States 10 years or longer (15.7%), and those who preferred English (17.9%). Overall, self-reported CHD and stroke prevalence were low (4.2% and 2.0% in men; 2.4% and 1.2% in women, respectively). In multivariate-adjusted models, hypertension and smoking were directly associated with CHD in both sexes as were hypercholesterolemia and obesity in women and diabetes in men (odds ratios [ORs], 1.5–2.2). For stroke, associations were positive with hypertension in both sexes, diabetes in men, and smoking in women (ORs, 1.7–2.6).
Among US Hispanic/Latino adults of diverse backgrounds, a sizeable proportion of men and women had adverse major risk factors; prevalence of adverse CVD risk profiles was higher among participants with Puerto Rican background, lower SES, and higher levels of acculturation.
High salt intake may affect left ventricular mass (LVM). We hypothesized that urinary sodium (UNa) and sodium / potassium ratio (UNa/K) are associated with LVM in a predominantly normotensive cohort young adults. The Coronary Artery Risk Development in Young Adults (CARDIA) study is a multicenter cohort of black and white men and women aged 30 ± 3.6 years at the time of baseline echocardiographic examination (1990–1991). Two-dimensionally guided M-mode LVM indexed to body size (gm/m2.7) was calculated and urinary sodium (UNa) and potassium (UK) excretion assessed (average of three 24-hour urinary samples, n=1,042). Linear and logistic regression analysis was used. Participants were 57% women, and 55% black. Only 4% were hypertensive. Mean±SD UNa, UK, and UNa/K ratio were 175.6±131.0 mmol/24hour, 56.4±46.3 mmol/24hour and 3.4±1.4, respectively. Participants in the highest vs. lowest UNa excretion quartile had the greatest LVM (37.5 vs. 34.0 g/m2.7, p<0.001). Adjusted for age, sex, education and race, LVM averaged 0.945gm/m2.7 higher per SD of UNa/K (p=0.001). The relationship between UNa/K and LVM persisted among 399 participants with repeat echocardiographic measures five years later. In logistic regression analysis adjusted for age, sex, education and race, each SD higher baseline UNa/K was associated with 23% and 38% greater chance of being in the highest quartile of LVM at baseline (OR 1.23; p=0.005) and five years later (OR 1.38; p=0.02). A higher sodium to potassium excretion ratio is significantly related to cardiac structure even among healthy young adults.
urinary sodium; urinary potassium; sodium / potassium ratio; left ventricular mass
Physical and Mental Component Summary (PCS, MCS, respectively) scales of SF- 36 health-related-quality-of-life have been associated with all-cause and cardiovascular disease (CVD) mortality. Their relationships with CVD incidence are unclear. This study purpose was to test whether PCS and/or MCS were associated with CVD incidence and death.
Postmenopausal women (aged 50–79 years) in control groups of the Women’s Health Initiative clinical trials (n = 20,308) completed the SF-36 and standardized questionnaires at trial entry. Health outcomes, assessed semi-annually, were verified with medical records. Cox regressions assessed time to selected outcomes during the trial phase (1993–2005).
A total of 1075 incident CVD events, 204 CVD-specific deaths, and 1043 total deaths occurred during the trial phase. Women with low versus high baseline PCS scores had less favorable health profiles at baseline. In multivariable models adjusting for baseline confounders, participants in the lowest PCS quintile (reference = highest quintile) exhibited 1.8 (95%CI: 1.4, 2.3), 4.7 (95%CI: 2.3, 9.4), and 2.1 (95%CI: 1.7, 2.7) times greater risk of CVD incidence, CVD-specific death, and total mortality, respectively, by trial end; whereas, MCS was not significantly associated with CVD incidence or death.
Physical health, assessed by self-report of physical functioning, is a strong predictor of CVD incidence and death in postmenopausal women; similar self-assessment of mental health is not. PCS should be evaluated as a screening tool to identify older women at high risk for CVD development and death.
Physical component summary; Mental component summary; Cardiovascular disease; All-cause death
Hispanics are the fastest growing minority group in the United States. The incidence of end-stage renal disease (ESRD) in Hispanics is higher than non-Hispanic Whites and Hispanics with chronic kidney disease (CKD) are at increased risk for kidney failure. Likely contributing factors to this burden of disease include diabetes and metabolic syndrome, both are common among Hispanics. Access to health care, quality of care, and barriers due to language, health literacy and acculturation may also play a role. Despite the importance of this public health problem, only limited data exist about Hispanics with CKD. We review the epidemiology of CKD in US Hispanics, identify the factors that may be responsible for this growing health problem, and suggest gaps in our understanding which are suitable for future investigation.
Chronic Kidney Disease; Hispanics; Health Care Disparities
A low cardiovascular disease (CVD) risk profile (untreated cholesterol < 200 mg/dl, untreated blood pressure < 120/<80 mmHg, never smoking, and no history of diabetes and myocardial infarction) in middle age is associated with markedly better health outcomes in older age, but few middle aged adults have this low risk profile. We examined whether adopting a healthy lifestyle throughout young adulthood is associated with presence of the low CVD risk profile in middle age.
Methods and Results
The CARDIA study sample consisted of 3,154 black and white participants aged 18 to 30 years at Year 0 (Y0, 1985-86) who attended the Year 0, 7 and 20 (Y0, Y7 and Y20) examinations. Healthy lifestyle factors (HLFs) defined at Y0, Y7 and Y20 included: 1) Average BMI < 25 kg/m2; 2) No or moderate alcohol intake; 3) higher healthy diet score; 4) higher physical activity score; and 5) Never smoking. Mean age (25 years) and percentage of women (56%) were comparable across groups defined by number of HLFs. The age-, sex- and race-adjusted prevalences of low CVD risk profile at Y20 were 3.0%, 14.6%, 29.5%, 39.2% and 60.7% for people with 0 or 1, 2, 3, 4, and 5 HLFs, respectively (p-trend <0.0001). Similar graded relationships were observed for each sex-race group (all p-trend<0.0001).
Maintaining a healthy lifestyle throughout young adulthood is strongly associated with low CVD risk profile in middle age. Public health and individual efforts are needed to improve adoption and maintenance of healthy lifestyles in young adults.
epidemiology; follow-up studies; risk factors; prevention
Few studies to date have described the prevalence of electrocardiographic (ECG) abnormalities in a biracial middle-aged cohort.
Methods and Results
Participants underwent measurement of traditional risk factors and 12-lead ECGs coded using both Minnesota Code (MC) and Novacode (NC) criteria. Among 2585 participants, of whom 57% were women and 44% were black (mean age 45 years), the prevalence of major and minor abnormalities were significantly higher (all P<0.001) among black men and women compared to whites. These differences were primarily due to higher QRS voltage and ST/T wave abnormalities among blacks. There was also a higher prevalence of Q waves (MC 1-1, 1-2, 1-3) than described by previous studies. These racial differences remained after multivariate adjustment for traditional cardiovascular (CV) risk factors.
Black men and women have a significantly higher prevalence of ECG abnormalities, independent of traditional CV risk factors, than whites in a contemporary cohort middle-aged participants.
Data are sparse regarding the long-term association of favorable levels of all major cardiovascular disease risk factors (RFs) (ie, low risk [LR]) with ankle-brachial index (ABI).
Methods and Results
In 2007–2010, the Chicago Healthy Aging Study reexamined a subset of participants aged 65 to 84 years from the Chicago Heart Association Detection Project in Industry cohort (baseline examination, 1967–1973). RF groups were defined as LR (untreated blood pressure ≤120/≤80 mm Hg, untreated serum cholesterol <200 mg/dL, body mass index <25 kg/m2, not smoking, no diabetes) or as 0 RFs, 1 RF, or 2+ RFs based on the presence of blood pressure ≥140/≥90 mm Hg or receiving treatment, serum cholesterol ≥240 mg/dL or receiving treatment, body mass index ≥30 kg/m2, smoking, or diabetes. ABI at follow-up was categorized as indicating PAD present (≤0.90), as borderline PAD (0.91 to 0.99), or as normal (1.00 to 1.40). We included 1346 participants with ABI ≤1.40. After multivariable adjustment, the presence of fewer baseline RFs was associated with a lower likelihood of PAD at 39-year follow-up (P for trend is <0.001). Odds ratios (95% CIs) for PAD in persons with LR, 0 RFs, or 1 RF compared with those with 2+ RFs were 0.14 (0.05 to 0.44), 0.28 (0.13 to 0.59), and 0.33 (0.16 to 0.65), respectively; findings were similar for borderline PAD (P for trend is 0.005). The association was mainly due to baseline smoking status, cholesterol, and diabetes. Remaining free of adverse RFs or improving RF status over time was also associated with PAD.
LR profile in younger adulthood (ages 25 to 45) is associated with the lowest prevalence of PAD and borderline PAD 39 years later.
aging; atherosclerosis; cardiovascular disease; peripheral artery disease; risk factors
Literature on the association of protein intake with body weight is inconsistent. Little is known about the relation of long-term protein intake to obesity. This study aimed to determine the association between protein intake and obesity. A cohort of 1,730 employed white men ages 40–55 years from the Chicago Western Electric Study was followed from 1958 to 1966. Diet was assessed twice with Burke’s comprehensive diet history method, at two baseline examinations; height, weight, and other covariates were measured annually by trained interviewers. Generalized estimating equation (GEE) was used to examine the relation of baseline total, animal, and vegetable protein intake to likelihood of being overweight or obese at sequential annual examinations. Dietary animal protein was positively related to overweight and obesity over seven years of follow up. With adjustment for potential confounders (age, education, cigarette smoking, alcohol intake, energy, carbohydrate and saturated fat intake, and history of diabetes or other chronic disease), the odds ratios (95% confidence intervals) for obesity were 4.62 (2.68–7.98, p for trend<0.01) for participants in the highest compared to the lowest quartile of animal protein and 0.58 (0.36, 0.95, p for trend=0.053) for those in the highest quartile of vegetable protein intake. A statistically significant, positive association was seen between animal protein intake and obesity; those in higher quartiles of vegetable protein intake had lower odds of being obese. These results indicate that animal and vegetable protein may relate differently to occurrence of obesity in the long run.
Dietary protein intake; overweight; obesity; nutrition; epidemiology
The obesity epidemic has focused attention on relationships of sugars and sugar-sweetened beverages (SSB) to cardiovascular risk factors. Here we report cross-sectional associations of SSB, diet beverages, sugars with blood pressure (BP) for UK and USA participants of the International Study of Macro/Micro-nutrients and Blood Pressure (INTERMAP). Data collected includes four 24-h dietary recalls, two 24-h urine collections, eight BP readings, questionnaire data for 2,696 people ages 40-59 from 10 USA/UK population samples. Associations of SSB, diet beverages, and sugars (fructose, glucose, sucrose) with BP were assessed by multiple linear regression. Sugar-sweetened beverage intake related directly to BP, P-values 0.005 to <0.001 (systolic BP), 0.14 to <0.001 (diastolic BP). Sugar-sweetened beverage intake higher by 1 serving/day (355 ml/24-h) was associated with systolic/diastolic BP differences of +1.6/+0.8 mm Hg (both P <0.001); +1.1/+0.4 mm Hg (P <0.001/<0.05) with adjustment for weight, height. Diet beverage intake was inversely associated with BP, P 0.41 to 0.003. Fructose- and glucose-BP associations were direct, with significant sugar-sodium interactions: for individuals with above-median 24-h urinary sodium excretion, fructose intake higher by 2 SD (5.6 %kcal) was associated with systolic/diastolic BP differences of +3.4/+2.2 mm Hg (both P <0.001); 2.5/1.7 mm Hg (both P 0.002) with adjustment for weight, height. Observed independent, direct associations of SSB intake and BP are consistent with recent trial data. These findings, plus adverse nutrient intakes among SSB consumers, and greater sugar-BP differences for persons with higher sodium excretion, lend support to recommendations that intake of SSB, sugars, and salt be substantially reduced.
Sugar-sweetened beverages; sodium; nutrition; blood pressure; epidemiology; population study
To estimate whether women aged 19–32 who fulfilled National Institutes of Health (NIH) criteria for polycystic ovary syndrome (PCOS) would be at a higher risk for subsequent development of incident diabetes, dyslipidemia, and hypertension, and to estimate whether normal-weight women with PCOS would have the same degree of cardiovascular risk as overweight women with PCOS.
We estimated the association of PCOS with incident diabetes, dyslipidemia, and hypertension over a period of 18 years among 1,127 white women and black women in the Coronary Artery Risk Development In young Adults (CARDIA) cohort. We classified women at baseline (ages 20–32) based on self-reported symptoms and/or biochemical hyperandrogenism using NIH PCOS criteria. We estimated the association of PCOS and subsequent cardiovascular risk factors, independent of baseline body mass index (BMI), using multivariable logistic regression. Additionally, among 746 women with a second assessment of PCOS at ages 34–46, we estimated the association of persistent PCOS with cardiovascular risk factors.
Of 1,127 women, 53 (4.7%) met criteria for PCOS at ages 20–32. PCOS was associated with a twofold higher odds of incident diabetes (23.1% versus 13.1%; adjusted OR (AOR) 2.4, 1.2–4.9) and dyslipidemia (41.9% versus 27.7%; AOR 1.9, 1.0–3.6) over 18 years; the association with incident hypertension was not significant (26.9% versus 26.3%; AOR 1.7, 0.8–3.3). Normal-weight women with PCOS (n=31) had a threefold higher odds of incident diabetes compared to normal weight women without PCOS (AOR 3.1, 1.2–8.0). Compared to those without PCOS (n=11), women with persistent PCOS had the highest odds of diabetes (AOR 7.2, 1.1–46.5).
PCOS is associated with subsequent incident diabetes and dyslipidemia, independent of BMI. Diabetes risk may be greatest for women with persistent PCOS symptoms.
Rates of heart disease and stroke vary markedly between north and south China. A 1H NMR spectroscopy-based Metabolome-Wide Association approach was used to identify urinary metabolites that discriminate between southern and northern Chinese population samples, to investigate population biomarkers that might relate to the difference in cardiovascular disease risk. NMR spectra were acquired from two 24-hour urine specimens per person for 523 northern and 244 southern Chinese participants in the INTERMAP Study of macro/micronutrients and BP. Discriminating metabolites were identified using Orthogonal Partial Least Squares Discriminant Analysis and assessed for statistical significance with conservative Family Wise Error Rate <0.01 to minimise false positive findings. Urinary metabolites significantly (P <1.2×10−16 to 2.9×10−69) higher in northern than southern Chinese populations included dimethylglycine, alanine, lactate, branched-chain amino acids (isoleucine, leucine, valine), N-acetyls of glycoprotein fragments (including uromodulin), N-acetyl neuraminic acid, pentanoic/heptanoic acid, methylguanidine; metabolites significantly (P <1.1×10−12 to 2×10−127) higher in the south were gut microbial co-metabolites (hippurate, 4-cresyl sulphate, phenylacetylglutamine; 2-hydroxyisobutyrate), succinate, creatine, scyllo-inositol, prolinebetaine, trans-aconitate. These findings indicate the importance of environmental influences (e.g., diet), endogenous metabolism and mammalian-gut microbial co-metabolism, that may help explain north-south China differences in cardiovascular disease risk.
1H-NMR; blood pressure; epidemiology; gut microbial co-metabolites; INTERMAP; metabolome wide association; metabonomics; nutrition
High throughput metabolic profiling via the metabolome-wide association study (MWAS) is a powerful new approach to identify biomarkers of disease risk, but there are methodological challenges: high dimensionality, high level of collinearity, the existence of peak overlap within metabolic spectral data, multiple testing and selection of a suitable significance threshold.
We define the metabolome-wide significance level (MWSL) as the threshold required to control the family wise error rate through a permutation approach. We used 1H NMR spectroscopic profiles of 24 hour urinary collections from the INTERMAP study. Our results show that the MWSL primarily depends on sample size and spectral resolution. The MWSL estimates can be used to guide selection of discriminatory biomarkers in MWA studies.
In a simulation study, we compare statistical performance of the MWSL approach to two variants of orthogonal partial least squares (OPLS) method with respect to statistical power, false positive rate and correspondence of ranking of the most significant spectral variables. Our results show that the MWSL approach as estimated by the univariate t-test is not outperformed by OPLS and offers a fast and simple method to detect disease-related discriminatory features in human NMR urinary metabolic profiles.
The Hispanic Community Health Study (HCHS)/Study of Latinos (SOL) is a comprehensive multi-center community based cohort study of Hispanics/Latinos in the United States. Its rationale, objectives, design and implementation are described in this paper.
The HCHS/SOL will recruit 16,000 men and women who self-identify as Hispanic or Latino, age 18-74 years, from a random sample of households in defined communities in the Bronx, Chicago, Miami and San Diego. The sites were selected so that the overall sample would consist of at least 2000 persons in each of the following origin designations: Mexican, Puerto Rican and Dominican, Cuban, and Central and South American. The study includes research in the prevalence of and risk factors for heart, lung, blood and sleep disorders, kidney and liver function, diabetes, cognitive function, dental conditions, and hearing disorders.
The HCHS/SOL will 1) characterize the health status and disease burden in the largest minority population in the U.S; 2) describe the positive and negative consequences of immigration and acculturation of Hispanics/Latinos to the mainstream U.S. life-styles, environment and health care opportunities; and 3) identify likely causal factors of many diseases in a population with diverse environmental exposures, genetic backgrounds and early life experiences.
Data from the Multiple Risk Factor Intervention Trial (MRFIT) show an independent direct association between starch intake and blood pressure (BP) in American men at higher risk of coronary heart disease (CHD). Cross-sectional INTERMAP data were used to assess relations of dietary starch intake to BP in men and women from four countries.
Data include 83 nutrients from four multi-pass 24-h dietary recalls and two timed 24-h urine collections; eight BP readings; and questionnaire data, for 4,680 participants ages 40–59 yr from 17 population samples in Japan, People's Republic of China, United Kingdom, and United States of America.
In multiple linear regression analyses – adjusted for urinary sodium, urinary potassium, consumption of alcohol, cholesterol, saturated fatty acids, polyunsaturated fatty acids, calcium, and other variables – starch intake higher by two standard deviations (14.1% kJ) was associated with systolic/diastolic BP differences of −1.0/−0.9 mm Hg (p =0.09, p <0.05). Results were similar with additional control for fibre, magnesium, or phosphorus; reduced to −0.5/−0.7 mm Hg (p =0.47, p =0.13) with separate adjustment for vegetable protein. Findings were similar for all INTERMAP men, for American men, and for American men at higher CHD risk.
INTERMAP data indicate that – if any – relations of starch intake to BP are modestly inverse. Current dietary guidelines for hypertension prevention and control remain relevant.
Blood pressure; cross-sectional studies; diet; dietary carbohydrates; dietary starch; epidemiology
The authors examined the associations of toenail selenium levels with blood concentrations of fibrinogen, high-sensitivity C-reactive protein (hs-CRP), and interleukin-6 (IL-6) in an 18-year follow-up study comprising 4,032 Americans aged 20–32 years at baseline (1987) from the Coronary Artery Risk Development in Young Adults (CARDIA) Trace Element Study. Toenail samples were collected in 1987, and selenium concentrations were measured by means of instrumental neutron-activation analysis. Fibrinogen level was analyzed in 1990, 1992, and 2005; hs-CRP was assessed in 1992, 2000, and 2005; and IL-6 was measured in 2005. After adjustment for potential confounders, no statistically significant associations between toenail selenium levels and any of the 3 inflammatory biomarkers were documented. Comparing the highest quintile of toenail selenium level with the lowest, odds ratios for elevated levels of fibrinogen (>460 mg/mL), hs-CRP (>3 μg/mL), and IL-6 (>3.395 pg/mL, 80th percentile) were 1.03 (95% confidence interval (CI): 0.77, 1.38; P for trend = 0.76), 1.02 (95% CI: 0.83, 1.27; P for trend = 0.92), and 0.98 (95% CI: 0.71, 1.36; P for trend = 0.82), respectively. Gender, race/ethnicity, smoking status, and selenium supplementation did not appreciably modify these results. This study found no associations between toenail selenium and inflammation as measured by fibrinogen, hs-CRP, and IL-6.
C-reactive protein; fibrinogen; inflammation; interleukin-6; nails; selenium
Isolated minor non-specific ST-segment and T-wave (NSSTA), minor and major electrocardiographic (ECG) abnormalities are established, independent risk markers for incident cardiovascular events. Their association with subclinical atherosclerosis has been postulated but is not clearly defined. The aim of this study is to define the association between ECG abnormalities and measures of subclinical atherosclerosis. We studied participants from MESA, a multi-ethnic sample of men and women aged 45–84 and free of clinical cardiovascular disease at enrollment. Baseline examination included measurement of traditional risk factors, resting 12-lead electrocardiograms, coronary artery calcium (CAC) measurement and common carotid intima-media thickness (CCIMT). Electrocardiograms were coded using Novacode criteria and were defined as having either minor abnormalities (e.g., minor non-specific STTA, first degree atrioventricular block, and QRS axis deviations) or major abnormalities (e.g., pathologic Q waves, major ST-segment and T-wave abnormalities, significant dysrhythmias and conduction system delays). Multivariable logistic and linear regressions were used to determine the cross-sectional associations of ECG abnormalities with CAC and common carotid-IMT. Among 6710 participants, 52.7% were women, with a mean age of 62 years. After multivariable-adjustment, isolated minor STTA, minor and major ECG abnormalities were not associated with the presence of CAC (>0) among men (OR 1.04, 95% CI 0.81–1.33; 1.10, 0.91–1.32; and 1.03, 0.81–1.31, respectively) or women (1.01, 0.82–1.24; 1.04, 0.87–1.23; and 0.94, 0.73–1.22, respectively). Lack of association remained consistent when using both log CAC and CC-IMT as continuous variables. ECG abnormalities are not associated with markers of subclinical atherosclerosis in a large multi-ethnic cohort.
Experimental and observational data suggest higher dietary intake of long-chain omega-3 polyunsaturated acids may lead to decreased risk of depressive disorders. We assessed multivariable-adjusted associations of fish consumption and dietary intakes of eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA] with depressive symptoms in a population-based sample of 3,317 African American and Caucasian men and women from the Coronary Artery Risk Development in Young Adults study (CARDIA).
Diet was assessed in Year 7 (1992–93) and depressive symptoms were measured in Years 10 (1995–96), 15 (2000–01), and 20 (2005–06) by the 20-item Center for Epidemiological Studies Depression Scale (CES-D). Depressive symptoms were defined as CES-D score ≥ 16 or self-reported use of antidepressant medication.
In the entire cohort, the highest quintiles of intakes of EPA (at least 0.03% energy), DHA (at least 0.05% energy), and EPA+DHA (at least 0.08% energy) were associated with lower risk of depressive symptoms at Year 10 (p-trends: 0.16, 0.10, 0.03, respectively). The observed inverse associations were more pronounced in women. For the total number of occasions with depressive symptoms, the multivariable adjusted odds ratios (95% confidence interval) in women were 0.75 (0.55–1.01) for fish intake; 0.66 (0.50–0.89), for EPA; 0.66 (0.49–0.89) for DHA; and 0.71 (0.52–0.95) for EPA+DHA, when comparing highest to lowest quintiles. Analyses of continuous CES-D scores revealed inverse associations with fourth root transformed omega-3 variables in women.
Our findings suggest that dietary intakes of fish and long-chain omega-3 fatty acids may be inversely associated with chronic depressive symptoms in women.
omega-3 fatty acids; depressive symptoms; EPA; DHA; fish
Urinary amino acid analysis is typically done by cation-exchange chromatography followed by post-column derivatization with ninhydrin and UV detection. This method lacks throughput and specificity. Two recently introduced stable isotope ratio mass spectrometric methods promise to overcome those shortcomings. Using two blinded sets of urine replicates and a certified amino acid standard, we compared the precision and accuracy of gas chromatography/mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) of propyl chloroformate and iTRAQ® derivatized amino acids, respectively, to conventional amino acid analysis. The GC-MS method builds on the direct derivatization of amino acids in diluted urine with propyl chloroformate, GC separation and mass spectrometric quantification of derivatives using stable isotope labeled standards. The LC-MS/MS method requires prior urinary protein precipitation followed by labeling of urinary and standard amino acids with iTRAQ® tags containing different cleavable reporter ions distinguishable by MS/MS fragmentation. Means and standard deviations of percent technical error (%TE) computed for 20 amino acids determined by amino acid analyzer, GC-MS, and iTRAQ®-LC-MS/MS analyses of 33 duplicate and triplicate urine specimens were 7.27±5.22, 21.18±10.94, and 18.34±14.67, respectively. Corresponding values for 13 amino acids determined in a second batch of 144 urine specimens measured in duplicate or triplicate were 8.39±5.35, 6.23±3.84, and 35.37±29.42. Both GC-MS and iTRAQ®-LC-MS/MS are suited for high-throughput amino acid analysis, with the former offering at present higher reproducibility and completely automated sample pretreatment, while the latter covers more amino acids and related amines.
amino acids; urine; gas chromatography-mass spectrometry; liquid chromatography-tandem mass spectrometry; amino acid analyzer; precolumn derivatization; stable isotope dilution; iTRAQ; propyl chloroformate
To examine the longitudinal association between toenail selenium levels and sub-clinical atherosclerosis over an 18-year period.
Toenail selenium concentrations were examined among 3112 Americans age 20–32 years in 1987 and measured by instrumental neutron-activation analysis. Subclinical atherosclerosis, including common, bulb and internal carotid intima-media thickness (CIMT), was measured in 2005 and coronary artery calcium (CAC) score in 2000 and 2005. General linear regression was developed examining the relation between toenail selenium levels and CIMTs, and logistic regression for repeated outcomes was employed estimating the risk of having CAC>0.
After adjustment for potential confounders, no associations were observed between toenail selenium levels and CIMTs as well as CAC score. Comparing participants in the highest with the lowest quintile of selenium, the CIMT was 0.005mm (SE=0.008mm, Ptrend=0.39), 0.018mm (SE=0.019mm, Ptrend=0.49), and 0.017mm (SE=0.014mm, Ptrend=0.21) thicker measured in common, bulb and internal carotid, respectively. The adjusted odds ratio of having CAC>0 was 0.95 (95%CI: 0.67–1.35; Ptrend=0.999).
No associations were observed between toenail selenium and measures of subclinical atherosclerosis among American young adults. This study does not support an atherosclerotic mechanism of selenium for risk reduction of cardiovascular disease.
toenail selenium; biomarker; sub-clinical atherosclerosis; carotid intima-media thickness; coronary artery calcium
Cardioprotective effects of long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) and fish consumption have been observed. However, data on the specific associations of these dietary factors with inflammation and endothelial activation are sparse. We conducted a cross-sectional study of 5,677 men and women from the MESA cohort including African Americans, Caucasians, Chinese and Hispanics, aged 45-84 years, and free of clinical cardiovascular disease. Dietary information was collected by self-administered food frequency questionnaire. Multivariable linear regression analyses were used to examine relations between intake of LC n-3 PUFAs, non-fried fish and fried fish and biomarkers of inflammation and endothelial activation. LC n-3 PUFA intakes were inversely associated with plasma concentrations of interleukin-6 (IL-6, P=0.01) and matrix metalloproteinase-3 (MMP-3, P=0.03) independent of age, body mass index, physical activity, smoking, alcohol consumption and dietary variables. Non-fried fish consumption was found inversely related to C-reactive protein (CRP, P=0.045) and IL-6 (P<0.01); and fried fish was observed being inversely related to soluble intercellular adhesion molecules-1 (sICAM-1) (P<0.01) but not associated with other biomarkers after adjustment for potential confounders. In conclusion, this study suggests that dietary intakes of LC n-3 PUFAs and fish are inversely associated with concentrations of some biomarkers reflecting lower levels of inflammation and endothelial activation. These results may partially explain the cardioprotective effects of fish consumption.
long-chain n-3 polyunsaturated fatty acids; fish oil; biomarker; inflammation; endothelial function
This study investigates differences in developing activities of daily living (ADL) disability among non-Hispanic Whites, African Americans, Hispanics interviewed in Spanish (Hispanic/Spanish), and Hispanics interviewed in English (Hispanic/English)
Six-year risk for disability development is estimated from 8161 participants age 65 or older free of baseline disability in a population-based sample. Mediating factors amenable to clinical and public health intervention on racial/ethnic difference are evaluated.
The risk for developing disability among Hispanic/English was similar to Whites (hazard ratio [HR] = 0.99, 95% confidence interval [CI]: 0.6, 1.4), but substantially elevated for African Americans (HR=1.6, 95%CI: 1.3, 1.9) and Hispanic/Spanish (HR=1.8, 95%CI: 1.4, 2.1). Adjustment for demographics, health, and socioeconomic status reduced a large portion of those disparities (African American adjusted HR=1.1, Hispanic/Spanish adjusted HR=1.2).
Excess risks for developing disability among older African Americans and Hispanic/Spanish compared to Whites are largely attenuated by health and socioeconomic differences. Language and culture specific programs to increase physical activity and promote weight maintenance may prove to be efficient strategies to both reduce national ADL disability rates in the future and reduce racial/ethnic disparities in disability.
ADL; African American; Hispanic; Chronic Disease; Aging
OBJECTIVE—The prevalence of type 2 diabetes among Hispanic and Asian Americans is increasing. These groups are largely comprised of immigrants who may be undergoing behavioral and lifestyle changes associated with development of diabetes. We studied the association between acculturation and diabetes in a population sample of 708 Mexican-origin Hispanics, 547 non–Mexican-origin Hispanics, and 737 Chinese participants in the Multi-Ethnic Study of Atherosclerosis (MESA).
RESEARCH DESIGN AND METHODS—Diabetes was defined as fasting glucose ≥126 mg/dl and/or use of antidiabetic medications. An acculturation score was calculated for all participants using nativity, years living in the U.S., and language spoken at home. The score ranged from 0 to 5 (0 = least acculturated and 5 = most acculturated). Relative risk regression was used to estimate the association between acculturation and diabetes.
RESULTS—For non–Mexican-origin Hispanics, the prevalence of diabetes was positively associated with acculturation score, after adjustment for sociodemographics. The prevalence of diabetes was significantly higher among the most acculturated versus the least acculturated non–Mexican-origin Hispanics (prevalence ratio 2.49 [95% CI 1.14−5.44]); the higher the acculturation score is, the higher the prevalence of diabetes (P for trend 0.059). This relationship between acculturation and diabetes was partly attenuated after adjustment for BMI or diet. Diabetes prevalence was not related to acculturation among Chinese or Mexican-origin Hispanics.
CONCLUSIONS—Among non–Mexican-origin Hispanics in MESA, greater acculturation is associated with higher diabetes prevalence. The relation is at least partly mediated by BMI and diet. Acculturation is a factor that should be considered when predictors of diabetes in racial/ethnic groups are examined.
Animal studies indicate that monosodium glutamate (MSG) can induce hypothalamic lesions and leptin resistance, possibly influencing energy balance, leading to overweight. This study examines the association between MSG intake and overweight in the human species. We conducted a cross-sectional study of 752 healthy Chinese (48.7% women), ages 40 to 59 years, randomly sampled from three rural villages in north and south China. The great majority of participants prepared their foods at home, without use of commercially processed foods. Diet was assessed with four in-depth multi-pass 24-hour recalls. Participants were asked to demonstrate MSG amounts added in food preparation. Amounts shaken out were weighed by trained interviewers. Overweight was defined as body mass index ≥25.0 kg/m2 or ≥23.0 (based on World Health Organization recommendations for Asian populations). Eighty-two percent of participants used MSG. Average intake was 0.33 gram/day (standard deviation=0.40). With adjustment for potential confounders including physical activity and total energy intake, MSG intake was positively related to body mass index. Prevalence of overweight was significantly higher in MSG users than non-users. For users in the highest tertile of MSG intake compared to non-users, the multivariable-adjusted odds ratios of overweight (body mass index ≥23.0 and ≥25.0) were 2.10 (95% CI, 1.13–3.90, P for trend across four MSG categories=0.03) and 2.75 (95% CI, 1.28–5.95, P=0.04). This research provides human data that MSG intake may be associated with increased risk of overweight independent of physical activity and total energy intake.
monosodium glutamate; overweight; leptin resistance; hypothalamic obesity; population study
Blood pressure (BP) may be implicated in associations observed between ambient particulate matter and cardiovascular morbidity and mortality. This study examined cross-sectional associations between short-term ambient fine particles (particulate matter ≤ 2.5 μm in aerodynamic diameter; PM2.5) and BP: systolic (SBP), diastolic (DBP), mean arterial (MAP), and pulse pressure (PP).
The study sample included 5,112 persons 45–84 years of age, free of cardiovascular disease at the Multi-Ethnic Study of Atherosclerosis baseline examination (2000–2002). Data from U.S. Environmental Protection Agency monitors were used to estimate ambient PM2.5 exposures for the preceding 1, 2, 7, 30, and 60 days. Roadway data were used to estimate local exposures to traffic-related particles.
Results from linear regression found PP and SBP positively associated with PM2.5. For example, a 10-μg/m3 increase in PM2.5 30-day mean was associated with 1.12 mmHg higher pulse pressure [95% confidence interval (CI), 0.28–1.97] and 0.99 mmHg higher systolic BP (95% CI, –0.15 to 2.13), adjusted for age, sex, race/ethnicity, income, education, body mass index, diabetes, cigarette smoking and environmental tobacco smoke, alcohol use, physical activity, medications, atmospheric pressure, and temperature. Results were much weaker and not statistically significant for MAP and DBP. Although traffic-related variables were not themselves associated with BP, the association between PM2.5 and BP was stronger in the presence of higher traffic exposure.
Higher SBP and PP were associated with ambient levels of PM2.5 and the association was stronger in the presence of roadway traffic, suggesting that impairment of blood pressure regulation may play a role in response to air pollution.
air pollution; blood pressure; cardiovascular disease; epidemiology; particulate matter