[Show abstract][Hide abstract] ABSTRACT: In moderate and severe CKD, the association of cholesterol with subsequent cardiovascular disease (CVD) is weak. We examined whether malnutrition or inflammation (M-I) modifies the risk relationship between cholesterol levels and CVD events in African Americans with hypertensive CKD and a GFR between 20 and 65 ml/min per 1.73 m². We stratified 990 participants by the presence or absence of M-I, defined as body mass index <23 kg/m² or C-reactive protein >10 mg/L at baseline. The primary composite outcome included cardiovascular death or first hospitalization for coronary artery disease, stroke, or congestive heart failure occurring during a median follow-up of 77 months. Baseline total cholesterol (212 ± 48 versus 212 ± 44 mg/dl) and overall incidence of the primary CVD outcome (19 versus 21%) were similar in participants with (n = 304) and without (n = 686) M-I. In adjusted analyses, the CVD composite outcome exhibited a significantly stronger relationship with total cholesterol for participants without M-I than for participants with M-I at baseline (P < 0.02). In the non-M-I group, the cholesterol-adjusted hazard ratio (HR) for CVD increased progressively across cholesterol levels: HR = 1.19 [95% CI; 0.77, 1.84] and 2.18 [1.43, 3.33] in participants with cholesterol 200 to 239 and ≥240 mg/dl, respectively (reference: cholesterol <200). In the M-I group, the corresponding HRs did not vary significantly by cholesterol level. In conclusion, the presence of M-I modifies the risk relationship between cholesterol level and CVD in African Americans with hypertensive CKD.
Journal of the American Society of Nephrology 12/2010; 21(12):2131-42. DOI:10.1681/ASN.2009121285 · 9.34 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The authors compared effects of macronutrients on self-reported appetite and selected fasting hormone levels. The Optimal Macronutrient Intake Trial to Prevent Heart Disease (OMNI-Heart) (2003-2005) was a randomized, 3-period, crossover feeding trial (n = 164) comparing the effects of 3 diets, each rich in a different macronutrient. Percentages of kilocalories of carbohydrate, fat, and protein were 48, 27, and 25, respectively, for the protein-rich diet; 58, 27, and 15, for the carbohydrate-rich diet; and 48, 37, and 15 for the diet rich in unsaturated fat. Food and drink were provided for each isocaloric 6-week period. Appetite was measured by visual analog scales. Pairwise differences between diets were estimated using generalized estimating equations. Compared with the protein diet, premeal appetite was 14% higher on the carbohydrate (P = 0.01) and unsaturated-fat (P = 0.003) diets. Geometric mean leptin was 8% lower on the protein diet than on the carbohydrate diet (P = 0.003). Obestatin levels were 7% and 6% lower on the protein diet than on the carbohydrate (P = 0.02) and unsaturated-fat (P = 0.004) diets, respectively. There were no between-diet differences for ghrelin. A diet rich in protein from lean meat and vegetables reduces self-reported appetite compared with diets rich in carbohydrate and unsaturated fat and can be recommended in a weight-stable setting. The observed pattern of hormone changes does not explain the inverse association between protein intake and appetite.
American journal of epidemiology 03/2009; 169(7):893-900. DOI:10.1093/aje/kwn415 · 5.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Inflammation and hemostasis may increase the risk of kidney function decline; however, data from prospective studies are sparse.
The Atherosclerosis Risk in Communities (ARIC) Study, a prospective observational cohort.
We used data from 14,854 middle-aged adults from 4 different US communities.
Markers of inflammation and hemostasis were examined.
The risk of kidney function decrease associated with these markers was studied. Glomerular filtration rate (GFR) was calculated from serum creatinine levels using the 4-variable Modification of Diet in Renal Disease (MDRD) Study equation. Chronic kidney disease (CKD) was defined as: (1) a decrease in estimated GFR to less than 60 mL/min/1.73 m2 from greater than 60 mL/min/1.73 m2 at baseline, or (2) a hospitalization discharge or death coded for CKD. Serum creatinine was measured at baseline and the 3- and 9-year follow-up visits. Hazard ratios (HRs) of CKD associated with increased levels of inflammatory and hemostatic variables were estimated by using multivariate Cox proportional hazards regression.
1,787 cases of CKD developed between 1987 and 2004. After adjusting for demographics, smoking, blood pressure, diabetes, lipid levels, prior myocardial infarction, antihypertensive use, alcohol use, year of marker measurement, and baseline renal function using estimated GFR, the risk of incident CKD increased with increasing quartiles of white blood cell count (HR quartile 4 versus quartile 1, 1.30; 95% confidence interval [CI], 1.12 to 1.50; P trend = 0.001), fibrinogen (HR, 1.25; 95% CI, 1.09 to 1.44; P < 0.001), von Willebrand factor (HR, 1.46; 95% CI, 1.26 to 1.68; P < 0.001), and factor VIIIc (HR, 1.39; 95% CI, 1.20 to 1.60; P < 0.001). A strong inverse association was found between serum albumin level and risk of CKD (HR, 0.63; 95% CI, 0.55 to 0.72; P < 0.001). No independent association was found with factor VIIc level.
Although we lacked a direct measure of kidney function, associations were robust to case definitions.
Markers of inflammation and hemostasis are associated with greater risk of kidney function decrease. Findings suggest that inflammation and hemostasis are antecedent pathways for CKD.
American Journal of Kidney Diseases 12/2008; 53(4):596-605. DOI:10.1053/j.ajkd.2008.10.044 · 5.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Circulating C-reactive protein concentration has been associated with colorectal cancer in some studies. Whether C-reactive protein is associated with earlier steps in the natural history of this cancer has not been published (aside from an abstract). Thus, we evaluated the association between plasma C-reactive protein concentration and development of colorectal adenoma in a nested case-control study.
Colorectal adenoma cases (n = 135) and matched controls (n = 269) who had a negative sigmoidoscopy or colonoscopy were identified between baseline in 1989 and 2000 from among participants in the CLUE II cohort of Washington County, Maryland. Cases were confirmed by medical record review. Controls were matched with cases on age, sex, race, date of blood draw, time since last meal, and type of endoscopy. The odds ratio (OR) of adenoma was estimated from conditional logistic regression models.
C-reactive protein concentrations were similar between colorectal adenoma cases and controls (median C-reactive protein, 1.31 vs. 1.38 mg/l; p = 0.13). The OR of colorectal adenoma among those in the highest fourth (>2.95 mg/l) of C-reactive protein concentration compared with the lowest fourth (<0.65 mg/l) was 0.61 (95% confidence interval, 0.29-1.25; p for trend = 0.25).
Pre-diagnostic plasma C-reactive protein concentration was not associated with an increased risk of colorectal adenoma. More work is needed to determine whether C-reactive protein is a valid marker of intra-colonic inflammation, and whether such inflammation contributes to the etiology of colorectal neoplasia.
Cancer Causes and Control 09/2008; 19(6):559-67. DOI:10.1007/s10552-008-9117-x · 2.74 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: C-reactive protein is a sensitive but nonspecific systemic marker of inflammation. Several prospective studies have investigated the association of prediagnostic circulating C-reactive protein concentrations with the development of colorectal cancer, but the results have been inconsistent. We performed a systematic review of prospective studies of the association between prediagnostic measurements of circulating high-sensitivity C-reactive protein and development of invasive colorectal cancer. Authors of original studies were contacted to acquire uniform data. We combined relative risks (RR) for colorectal cancer associated with a one unit change in natural logarithm-transformed high-sensitivity C-reactive protein using inverse variance weighted random effects models. We identified eight eligible studies, which included 1,159 colorectal cancer cases and 37,986 controls. The summary RR per one unit change in natural log-transformed high-sensitivity C-reactive protein was 1.12 (95% confidence intervals [CI], 1.01-1.25) for colorectal cancer, 1.13 (95% CI, 1.00-1.27) for colon cancer, and 1.06 (95% CI, 0.86-1.30) for rectal cancer. The association was stronger in men (RR, 1.18; 95% CI, 1.04-1.34) compared to women (RR, 1.09; 95% CI, 0.93-1.27) but this difference was sensitive to the findings from a single study. Prediagnostic high-sensitivity C-reactive protein concentrations were weakly associated with an increased risk for colorectal cancer. More work is needed to understand the extent to which circulating high-sensitivity C-reactive protein or other blood inflammatory markers are related to colonic inflammation.
International Journal of Cancer 09/2008; 123(5):1133-40. DOI:10.1002/ijc.23606 · 5.09 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To improve methods for long-term weight management, the Weight Loss Maintenance (WLM) trial, a four-center randomized trial, was conducted to compare alternative strategies for maintaining weight loss over a 30-month period. This paper describes methods and results for the initial 6-month weight-loss program (Phase I).
Eligible adults were aged > or =25, overweight or obese (BMI=25-45 kg/m2), and on medications for hypertension and/or dyslipidemia. Anthropomorphic, demographic, and psychosocial measures were collected at baseline and 6 months. Participants (n=1685) attended 20 weekly group sessions to encourage calorie restriction, moderate-intensity physical activity, and the DASH (dietary approaches to stop hypertension) dietary pattern. Weight-loss predictors with missing data were replaced by multiple imputation.
Participants were 44% African American and 67% women; 79% were obese (BMI> or =30), 87% were taking anti-hypertensive medications, and 38% were taking antidyslipidemia medications. Participants attended an average of 72% of 20 group sessions. They self-reported 117 minutes of moderate-intensity physical activity per week, kept 3.7 daily food records per week, and consumed 2.9 servings of fruits and vegetables per day. The Phase-I follow-up rate was 92%. Mean (SD) weight change was -5.8 kg (4.4), and 69% lost at least 4 kg. All race-gender subgroups lost substantial weight: African-American men (-5.4 kg +/- 7.7); African-American women (-4.1 kg +/- 2.9); non-African-American men (-8.5 kg +/- 12.9); and non-African-American women (-5.8 kg +/- 6.1). Behavioral measures (e.g., diet records and physical activity) accounted for most of the weight-loss variation, although the association between behavioral measures and weight loss differed by race and gender groups.
The WLM behavioral intervention successfully achieved clinically significant short-term weight loss in a diverse population of high-risk patients.
American Journal of Preventive Medicine 08/2008; 35(2):118-26. DOI:10.1016/j.amepre.2008.04.013 · 4.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To investigate the hypothesis that intrauterine growth restriction might produce a longstanding pro-inflammatory tendency, we investigated the association of low birth weight with blood levels of markers of inflammation and endothelial activation in middle-aged adults.
The ARIC Study enrolled subjects aged 45-64 years sampled from four U.S. communities. An inflammation/endothelial activation score from 0 to 6 was created, one point being given for each above-median value of white blood cell count, fibrinogen, von Willebrand factor and Factor VIII, and for each below-median value of albumin and activated partial thromboplastin time.
Of the 9809 individuals reporting birth weight and having all inflammation/endothelial markers and covariates, 349 (3.6%) reported low birth weight (LBW). The mean (standard deviation) score was 3.5 (1.5) for those with and 3.1 (1.6) for those without LBW (p<0.001). In robust poisson regression models adjusting for gender, ethnicity, age, study center, educational level, and current drinking and smoking status and amount, those with LBW were more likely to have a high score (> or =4 points) (RR=1.16, 95% CI: 1.05-1.29).
In the ARIC Study, LBW predicted greater inflammation and endothelial activation, as indicated by the higher score of blood markers, consistent with the hypothesis that early life events may result in a hyper-responsive innate immune system. Such a pro-inflammatory tendency could help explain the association of low birth weight with elements of the metabolic syndrome and ischemic heart disease.
International journal of cardiology 06/2008; 134(3):371-7. DOI:10.1016/j.ijcard.2008.02.024 · 4.04 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Behavioral weight loss interventions achieve short-term success, but re-gain is common.
To compare 2 weight loss maintenance interventions with a self-directed control group.
Two-phase trial in which 1032 overweight or obese adults (38% African American, 63% women) with hypertension, dyslipidemia, or both who had lost at least 4 kg during a 6-month weight loss program (phase 1) were randomized to a weight-loss maintenance intervention (phase 2). Enrollment at 4 academic centers occurred August 2003-July 2004 and randomization, February-December 2004. Data collection was completed in June 2007.
After the phase 1 weight-loss program, participants were randomized to one of the following groups for 30 months: monthly personal contact, unlimited access to an interactive technology-based intervention, or self-directed control. Main Outcome Changes in weight from randomization.
Mean entry weight was 96.7 kg. During the initial 6-month program, mean weight loss was 8.5 kg. After randomization, weight regain occurred. Participants in the personal-contact group regained less weight (4.0 kg) than those in the self-directed group (5.5 kg; mean difference at 30 months, -1.5 kg; 95% confidence interval [CI], -2.4 to -0.6 kg; P = .001). At 30 months, weight regain did not differ between the interactive technology-based (5.2 kg) and self-directed groups (5.5 kg; mean difference -0.3 kg; 95% CI, -1.2 to 0.6 kg; P = .51); however, weight regain was lower in the interactive technology-based than in the self-directed group at 18 months (mean difference, -1.1 kg; 95% CI, -1.9 to -0.4 kg; P = .003) and at 24 months (mean difference, -0.9 kg; 95% CI, -1.7 to -0.02 kg; P = .04). At 30 months, the difference between the personal-contact and interactive technology-based group was -1.2 kg (95% CI -2.1 to -0.3; P = .008). Effects did not differ significantly by sex, race, age, and body mass index subgroups. Overall, 71% of study participants remained below entry weight.
The majority of individuals who successfully completed an initial behavioral weight loss program maintained a weight below their initial level. Monthly brief personal contact provided modest benefit in sustaining weight loss, whereas an interactive technology-based intervention provided early but transient benefit.
clinicaltrials.gov Identifier: NCT00054925.
JAMA The Journal of the American Medical Association 04/2008; 299(10):1139-48. DOI:10.1001/jama.299.10.1139 · 35.29 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Parental hypertension is used to classify hypertension risk in young adults, but the long-term association of parental hypertension with blood pressure (BP) change and risk of hypertension over the adult life span has not been well studied.
We examined the association of parental hypertension with BP change and hypertension risk from young adulthood through the ninth decade of life in a longitudinal cohort of 1160 male former medical students with 54 years of follow-up.
In mixed-effects models using 29 867 BP measurements, mean systolic and diastolic BP readings were significantly higher at baseline among participants with parental hypertension. The rate of annual increase was slightly higher for systolic (0.03 mm Hg, P= .04), but not diastolic, BP in those with parental hypertension. After adjustment for baseline systolic and diastolic BP and time-dependent covariates--body mass index, alcohol consumption, coffee drinking, physical activity, and cigarette smoking--the hazard ratio (95% confidence interval [CI]) of hypertension development was 1.5 (1.2-2.0) for men with maternal hypertension only, 1.8 (1.4-2.4) for men with paternal hypertension only, and 2.4 (1.8-3.2) for men with hypertension in both parents compared with men whose parents never developed hypertension. Early-onset (at age <or=55 years) hypertension in both parents imparted a 6.2-fold higher adjusted risk (95% CI, 3.6-10.7) for the development of hypertension throughout adult life and a 20.0-fold higher adjusted risk (95% CI, 8.4-47.9) at the age of 35 years.
Hypertension in both mothers and fathers has a strong independent association with elevated BP levels and incident hypertension over the course of adult life.
Archives of Internal Medicine 04/2008; 168(6):643-8. DOI:10.1001/archinte.168.6.643 · 17.33 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: For most individuals, long-term maintenance of weight loss requires long-term, supportive intervention. Internet-based weight loss maintenance programs offer considerable potential for meeting this need. Careful design processes are required to maximize adherence and minimize attrition.
This paper describes the development, implementation and use of a Web-based intervention program designed to help those who have recently lost weight sustain their weight loss over 1 year.
The weight loss maintenance website was developed over a 1-year period by an interdisciplinary team of public health researchers, behavior change intervention experts, applications developers, and interface designers. Key interactive features of the final site include social support, self-monitoring, written guidelines for diet and physical activity, links to appropriate websites, supportive tools for behavior change, check-in accountability, tailored reinforcement messages, and problem solving and relapse prevention training. The weight loss maintenance program included a reminder system (automated email and telephone messages) that prompted participants to return to the website if they missed their check-in date. If there was no log-in response to the email and telephone automated prompts, a staff member called the participant. We tracked the proportion of participants with at least one log-in per month, and analyzed log-ins as a result of automated prompts.
The mean age of the 348 participants enrolled in an ongoing randomized trial and assigned to use the website was 56 years; 63% were female, and 38% were African American. While weight loss data will not be available until mid-2008, website use remained high during the first year with over 80% of the participants still using the website during month 12. During the first 52 weeks, participants averaged 35 weeks with at least one log-in. Email and telephone prompts appear to be very effective at helping participants sustain ongoing website use.
Developing interactive websites is expensive, complex, and time consuming. We found that extensive paper prototyping well in advance of programming and a versatile product manager who could work with project staff at all levels of detail were essential to keeping the development process efficient.
Journal of Medical Internet Research 02/2008; 10(1):e1. DOI:10.2196/jmir.931 · 3.43 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The Seven Countries Study, reported by Ancel Keys in 1970, was the first substantive epidemiological evidence to support the
hypothesis that multiple dietary factors determine coronary heart disease (CHD) risk. This seminal longitudinal study of populations
in Europe, Asia, and the United States was conducted with rigorous, standardized dietary data collection and meticulously
tracked clinical outcomes. A striking finding was the apparent large CHD risk reduction associated with consumption of a “Crete,”
a.k.a. “Mediterranean” diet. Since this report, further research has attempted to confirm these findings and characterize
features of the diet which may account for the substantial reduction in CHD risk.
[Show abstract][Hide abstract] ABSTRACT: Lifestyle modification can reduce blood pressure and lower cardiovascular risk. Established recommendations include weight loss, sodium reduction, and increased physical activity. PREMIER studied the effects of lifestyle interventions based on established recommendations alone and with the addition of the Dietary Approaches to Stop Hypertension (DASH) dietary pattern. This analysis aimed to assess the interventions' impact on cardiometabolic variables in participants with, compared with those without, metabolic syndrome. The primary outcome was 6-month change in systolic blood pressure. Participants with prehypertension or stage-1 hypertension were randomly assigned to an advice only control group, a 6-month intensive behavioral intervention group of established recommendations (EST), or an established recommendations plus DASH group (EST+DASH). Metabolic syndrome was defined per National Cholesterol and Education Program Adult Treatment Panel III. We used general linear models to test intervention effects on change in blood pressure, lipids, and insulin resistance (homeostasis model assessment), in subgroups defined by the presence or absence of metabolic syndrome. Of 796 participants, 399 had metabolic syndrome. Both EST and EST+DASH reduced the primary outcome variable, systolic blood pressure. Within the EST+DASH group, those with and without metabolic syndrome responded similarly (P=0.231). However, within EST, those with metabolic syndrome had a poorer response, with a decrease in systolic blood pressure of 8.4 mm Hg versus 12.0 mm Hg in those without metabolic syndrome (P=0.002). Thus, metabolic syndrome attenuated the systolic blood pressure reduction of EST, but this attenuation was overcome in EST+DASH. Finally, diastolic blood pressure, lipids, and homeostasis model assessment responded similarly to both interventions regardless of metabolic syndrome status. Our data suggest that strategies for lowering BP in individuals with metabolic syndrome may be enhanced by recommendations to adopt the DASH dietary pattern.
[Show abstract][Hide abstract] ABSTRACT: African Americans are at increased risk of kidney failure caused by hypertension. The primary objective of the African American Study of Kidney Disease and Hypertension (AASK) Cohort Study is to identify risk factors for progressive kidney disease in African Americans with hypertensive chronic kidney disease in the setting of recommended antihypertensive therapy.
On completion of the AASK Trial, a randomized, double-blind, 3 x 2 factorial trial, participants who had not yet begun dialysis treatment or undergone kidney transplantation were invited to enroll in a prospective Cohort Study. Cohort Study participants received recommended antihypertensive drug therapy, including high rates of angiotensin-converting enzyme-inhibitor (73%) and angiotensin receptor blocker (10%) use with a blood pressure goal of less than 130/80 mm Hg.
Baseline clinical and demographic characteristics are described separately at the baseline of the AASK Trial and Cohort Study.
Of 1,094 persons enrolled in the AASK Trial (June 1995 to September 2001; mean age, 55 years; 61% men), 691 enrolled in the AASK Cohort Study (April 2002 to present), 299 died or reached dialysis therapy or transplantation, and 104 declined to participate in the AASK Cohort Study. Mean baseline systolic/diastolic blood pressures were 150/96 mm Hg in the Trial and 136/81 mm Hg in the Cohort Study. Cohort Study participants had greater serum creatinine levels at the start of the Cohort Study (2.3 versus 1.8 mg/dL [203 versus 159 micromol/L]), corresponding to an estimated glomerular filtration rate of 43.8 versus 50.3 mL/min/1.73 m2 (0.73 versus 0.84 mL/s/1.73 m2), than Trial participants and greater urine protein-creatinine ratios (0.38 versus 0.19 mg/mg, respectively). Individuals who were eligible, but declined to participate in the Cohort Study, had greater systolic blood pressure, but similar kidney function.
Some parameters, such as iothalamate glomerular filtration rate, urinary albumin level, echocardiogram, and ambulatory blood pressure, were not performed in both the Trial and the Cohort Study, limiting the ability to evaluate changes in these parameters over time.
Despite well-controlled blood pressure in the AASK Trial, Cohort Study participants still had evidence of progressive chronic kidney disease. Thus, the AASK Cohort Study is well positioned to address its primary objective.
American Journal of Kidney Diseases 07/2007; 50(1):78-89, 89.e1. DOI:10.1053/j.ajkd.2007.03.004 · 5.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Several studies suggest that weight loss reduces C-reactive protein (CRP) level; however, the consistency and magnitude of this effect has not been well characterized. Our objective was to test the hypothesis that weight loss is directly related to a decline in CRP level.
We searched the Cochrane Controlled Trials Register and MEDLINE databases and conducted hand searches and reviews of bibliographies to identify relevant weight loss intervention studies.
We included all weight loss intervention studies that had at least 1 arm that was a surgical, lifestyle, dietary, and/or exercise intervention. Abstracts were independently selected by 2 reviewers.
Two reviewers independently abstracted data on the characteristics of each study population, weight loss intervention, and change in weight and CRP level from each arm of all included studies.
We analyzed the mean change in CRP level (milligrams per liter) and the mean weight change (kilograms), comparing the preintervention and postintervention values from each arm of 33 included studies using graphical displays of these data and weighted regression analyses to quantify the association.
Weight loss was associated with a decline in CRP level. Across all studies (lifestyle and surgical interventions), we found that for each 1 kg of weight loss, the mean change in CRP level was -0.13 mg/L (weighted Pearson correlation, r = 0.85). The weighted correlation for weight and change in CRP level in the lifestyle interventions alone was 0.30 (slope, 0.06). The association appeared roughly linear.
Our results suggest that weight loss may be an effective nonpharmacologic strategy for lowering CRP level.
Archives of Internal Medicine 02/2007; 167(1):31-9. DOI:10.1001/archinte.167.1.31 · 17.33 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Serum uric acid has been positively associated with incident hypertension, but previous studies have had limited ability to explore this relationship across sex and ethnic strata. We sought to evaluate this association in a biethnic cohort of middle-aged men and women. Participants in the Atherosclerosis Risk in Communities (ARIC) study who were free of hypertension at baseline (N=9104) were evaluated for hypertension at 3-year intervals over 4 examinations. Adjusted Cox proportional hazards models evaluated risk of incident hypertension or progression of blood category for each SD higher baseline serum uric acid. At baseline, the mean age was 53.3 years (range: 45 to 64 years), with a mean (SD) systolic blood pressure of 113.8 (12.2) mm Hg, mean diastolic blood pressure of 70.2 (8.6) mm Hg, and mean serum uric acid of 5.7 (1.4). Higher serum uric acid was associated with greater risk of hypertension in the overall cohort (hazard ratio for each SD of higher uric acid [95% CI]: 1.10 [1.04 to 1.15]) and in subgroup analyses (black men: 1.32 [1.14 to 1.54]; black women: 1.16 [1.03 to 1.31]; white men: 1.01 [0.94 to 1.09]; white women: 1.04 [0.96 to 1.11]), after adjustment for age, baseline blood pressure, body mass index, renal function, diabetes, and smoking. The pattern was similar when modeling blood pressure progression (overall: 1.10 [1.05 to 1.14]; black men: 1.26 [1.11 to 1.42]; black women: 1.18 [1.06 to 1.31]; white men: 1.05 [0.99 to 1.11]; white women: 1.05 [1.00 to 1.12]). In conclusion, serum uric acid was positively associated with incident hypertension over 9 years of follow-up, and this relationship was stronger in blacks than in whites. More research is warranted concerning the physiological and clinical consequences of hyperuricemia, especially in blacks.
[Show abstract][Hide abstract] ABSTRACT: Macronutrients are those nutrients (protein, fat, and carbohydrate) that provide energy. The purpose of this review is to highlight findings of three large-scale, isocaloric feeding studies: the Dietary Approaches to Stop Hypertension (DASH) trial, the DASH-Sodium trial, and the Optimal Macro-Nutrient Intake to Prevent Heart Disease (OmniHeart) trial. Each of these trials tested the effects of diets with different macronutrient profiles on traditional cardiovascular disease (CVD) risk factors (ie, blood pressure and blood lipids) in the setting of stable weight. The DASH and DASH-sodium trials demonstrated that a carbohydrate-rich diet that emphasizes fruits, vegetables, and low-fat dairy products and that is reduced in saturated fat, total fat, and cholesterol substantially lowered blood pressure and low-density lipoprotein cholesterol. OmniHeart demonstrated that partial replacement of carbohydrate with either protein (about half from plant sources) or with unsaturated fat (mostly monounsaturated fat) can further reduce blood pressure, low-density lipoprotein cholesterol, and coronary heart disease risk. Results from these trials highlight the importance of macronutrients as a determinant of CVD risk. Furthermore, these results also document substantial flexibility that should enhance the ability of individuals to consume a heart-healthy diet.
Current Atherosclerosis Reports 12/2006; 8(6):460-5. DOI:10.1007/s12170-007-0008-6 · 3.42 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To investigate the association between stature-related measurements (height, leg length, and leg length-to-height ratio) and adiposity, insulin resistance, and glucose intolerance.
We conducted a cross-sectional analysis of a nationally representative sample of 7,424 adults aged 40-74 years, from the Third National Health and Nutrition Examination Survey (1988-1994). The main outcome measures were percent body fat, homeostasis model assessment of insulin resistance (HOMA-IR), and glucose intolerance based on the World Health Organization's 1985 criteria for an oral glucose tolerance test.
Shorter height and leg length, and lower leg length-to-height ratio, were associated with higher percent body fat, especially in women. Lower leg length-to-height ratio was associated with greater insulin resistance estimated by HOMA-IR. In multinomial regression models adjusting for potential confounders, including percent body fat, the relative prevalence of type 2 diabetes per 1-SD lower values in height, leg length, and leg length-to-height ratio were 1.10 (95% CI 0.94-0.29), 1.17 (0.98-1.39), and 1.19 (1.02-1.39), respectively.
Our study supports the hypothesis that adult markers of prepubertal growth, especially leg length-to-height ratio, are associated with adiposity, insulin resistance, and type 2 diabetes in the general U.S. population.
Diabetes Care 08/2006; 29(7):1632-7. DOI:10.2337/dc05-1997 · 8.42 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The main 6-month results from the PREMIER trial showed that comprehensive behavioral intervention programs improve lifestyle behaviors and lower blood pressure.
To compare the 18-month effects of 2 multicomponent behavioral interventions versus advice only on hypertension status, lifestyle changes, and blood pressure.
Multicenter, 3-arm, randomized trial conducted from January 2000 through November 2002.
4 clinical centers and a coordinating center.
810 adult volunteers with prehypertension or stage 1 hypertension (systolic blood pressure, 120 to 159 mm Hg; diastolic blood pressure, 80 to 95 mm Hg). Interventions: A multicomponent behavioral intervention that implemented long-established recommendations ("established"); a multicomponent behavioral intervention that implemented the established recommendations plus the Dietary Approaches to Stop Hypertension (DASH) diet ("established plus DASH"); and advice only.
Lifestyle variables and blood pressure status. Follow-up for blood pressure measurement at 18 months was 94%.
Compared with advice only, both behavioral interventions statistically significantly reduced weight, fat intake, and sodium intake. The established plus DASH intervention also statistically significantly increased fruit, vegetable, dairy, fiber, and mineral intakes. Relative to the advice only group, the odds ratios for hypertension at 18 months were 0.83 (95% CI, 0.67 to 1.04) for the established group and 0.77 (CI, 0.62 to 0.97) for the established plus DASH group. Although reductions in absolute blood pressure at 18 months were greater for participants in the established and the established plus DASH groups than for the advice only group, the differences were not statistically significant.
The exclusion criteria and the volunteer nature of this cohort may limit generalizability. Although blood pressure is a well-accepted risk factor for cardiovascular disease, the authors were not able to assess intervention effects on clinical cardiovascular events in this limited time and with this sample size.
Over 18 months, persons with prehypertension and stage 1 hypertension can sustain multiple lifestyle modifications that improve control of blood pressure and could reduce the risk for chronic disease.
Annals of internal medicine 05/2006; 144(7):485-95. · 17.81 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Chronic inflammation has been implicated in the pathogenesis of many common chronic diseases, including cancer. C-reactive protein (CRP) concentration is a non-specific serum marker of inflammation, and higher levels have been observed among individuals who go on to develop cardiovascular disease. Nested case-control studies were conducted within the CLUE II study, a community-based cohort, to examine the association between CRP concentrations and subsequent development of colorectal or prostate cancer. CRP concentrations were higher among individuals who went on to develop colon cancer, but not rectal or prostate cancer, compared with controls. The association between CRP concentrations and development of colon cancer is consistent with other evidence suggesting a role of inflammation and cancer. Preventive interventions that decrease systemic chronic inflammation have the potential to reduce certain types of cancer as well as cardiovascular disease. However, the potential benefits of anti-inflammatory chemopreventive agents must be weighed against their adverse effects before widespread use is recommended.
European Journal of Cancer 05/2006; 42(6):704-7. DOI:10.1016/j.ejca.2006.01.008 · 5.42 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Oxidation of LDL (oxLDL) is thought to have an important role in early stages of atherogenesis. Antibody to oxLDL (Ab-oxLDL) has been proposed as a biomarker which might be directly associated with oxidative stress. Yet studies designed to test this hypothesis are lacking. We tested the hypothesis that consumption of a healthy diet rich in fruits and vegetables and reduced in saturated fat, total fat, and cholesterol will concomitantly reduce oxidative stress and Ab-oxLDL.
One hundred and three healthy individuals were randomly assigned to consume a typical American (control) diet or the DASH diet rich in fruits, vegetables and low-fat dairy products and reduced in fat (27%), saturated fat (7%), and cholesterol (150 mg/day) for 3 months. Outcomes were urinary isoprostanes (in vivo marker of oxidative stress), oxygen radical absorbing capacity (ORAC, an in vitro assay measuring antioxidant activity in serum), and Ab-oxLDL measured at baseline, 1-3 months of feeding.
Compared to the control diet, consumption of the DASH diet significantly lowered urinary isoprostane (-226 pg/ml, 95% CI: -420 to -32, P=0.023). Compared with the control group, change in ORAC was higher in the DASH group, 143 trolox units/ml (95% CI: -23 to 308, P=0.091). In comparison with the control diet, increased titers of Ab-oxLDL (37 mU/ml [95% CI: 16-57, P=0.006]) were seen after consumption of the DASH diet. Higher titers of Ab-oxLDL occurred at month 2 (56 mU/ml, 95% CI: 20-90, P=0.004) and month 3 (41 mU/ml, 95% CI: -6 to 88, P=0.082), after initially small increases at month 1 (20 mU/ml, 95% CI: -10 to 51, P=0.176). End-of-study increases in AB-oxLDL were highly correlated with increased ORAC (Spearman's rho=0.46, P<0.0001), but not with changes in specific carotenoids, tocopherols or with change in LDL cholesterol (each: P>0.10).
Consumption of a healthy diet replete in antioxidants reduced oxidative stress (urinary isoprostanes) yet increased Ab-oxLDL. This indirect association of Ab-oxLDL with urinary isoprostanes hinders use of Ab-oxLDL as a marker of oxidative damage.