Feasibility and acceptability of a remotely-delivered behavioural health coaching intervention to limit gestational weight gain

INTRODUCTION

Gestational weight gain (GWG) and postpartum weight retention (PPWR) are significant, potentially modifiable, contributors to women's future weight and health trajectories. There is a need for feasible and patient-centered (i.e., convenient, remotely-delivered, technology-enhanced, and accessible through the prenatal care setting) behavioural interventions that limit GWG and PPWR. This study tests the feasibility and acceptability of a remotely-delivered behavioural health coaching intervention to limit gestational weight gain and postpartum weight retention.

METHODS

Pregnant women (11-16 weeks gestation) were recruited from two prenatal clinics and randomized to the active intervention or health education comparison group. Completion of the program was monitored and perceived helpfulness was rated (0-100).

RESULTS

Twenty-six women were randomized (n = 13 per arm; mean age = 31.6 years, SD = 3.6; mean BMI = 26.7 kg/m2, SD = 7.4). Participants completed a median of 18 coaching calls and 16/19 learning activities during pregnancy, and a median of 6 calls and 5/6 learning activities postpartum. They logged weights at least once/week for a median of 36/38 expected weeks and tracked daily calories and exercise for a median of 154/266 days and 72/266 days, respectively. Median (Q1, Q3) helpfulness ratings of the program during pregnancy were 80 (64, 91) and 62 (50, 81) postpartum; helpfulness ratings of coaching calls were 85 (58, 98). At 37 weeks gestation, 77% of participants achieved IOM weight gain recommendations compared to 54% in the comparison group.

CONCLUSIONS

This study provides evidence for the feasibility and acceptability of a remotely-delivered behavioural weight control intervention in pregnancy and postpartum.

Long-term retention in an employer-based, commercial weight-loss programme

The aim of this study is to examine factors associated with long-term retention in a commercial weight-loss programme. We conducted a retrospective analysis of an employer-based, commercial programme from 2013 to 2016. Our dependent variable was 'long-term retention', defined as continuously enrolled participants who actively engaged through coach calls at 6 and 12 months. Independent variables included baseline demographics, programme engagement and weight change. We conducted multivariate logistic regression analyses assessing for differences in long-term retention by several factors, adjusted for employer clustering. Overall, 68.3% were retained at 6% and 45.9% at 12 months. Greater number of coach calls and website logins during the first 3 months significantly increased the odds of long-term retention, while having chronic conditions significantly decreased the odds. Weight-loss success (≥5% loss at 6 months) was significantly associated with increased odds of retention (12-month: odds ratio [OR] 2.80, P < 0.001), while early weight-loss failure (≥0% weight change at 1 month) significantly decreased odds of retention (12-month: OR 0.66, P = 0.008). In an employer-based, commercial weight loss programme, greater early programme engagement was associated with long-term retention. Given these programmes' popularity and potential reach, our results could be used to develop and test strategies designed to improve retention in commercial weight-loss programmes.

Factors associated with early dropout in an employer-based commercial weight-loss program

OBJECTIVE

Minimizing program dropout is essential for weight-loss success, but factors that influence dropout among commercial programs are unclear. This study's objective was to determine factors associated with early dropout in a commercial weight-loss program.

METHODS

A retrospective analysis of a remotely delivered, employer-based commercial program from 2013 to 2016 was conducted. The dependent variable was 'early dropout', defined as enrollees who disengaged from telephone coaching by month 2's end. Independent variables included demographics, program website engagement and early weight change. Multivariate logistic regression analyses were used to assess for differences in early dropout by several factors, adjusted for employer clustering.

RESULTS

Of the 5,274 participants, 26.8% dropped out early. Having ≥1 chronic condition (odds ratio [OR] 1.41, p < 0.001) and 'weight-loss failure' defined as ≥0% weight change at month 1's end (OR 1.86, p < 0.001) had significantly increased odds of early dropout. Increasing age by 10-year intervals (OR 0.90, p = 0.002) and 'meeting the website login goal' defined as ≥90 logins in 3 months (OR 0.13, p < 0.001) significantly decreased the odds of early dropout.

CONCLUSIONS

Presence of comorbidities, less online engagement and weight-loss failure were associated with early dropout in a commercial program. Strategies to prevent dropout among high-risk participants, such as increased support or program tailoring, should be developed and tested.

Perceived helpfulness of the individual components of a behavioural weight loss program: results from the Hopkins POWER Trial

Background

Behavioural weight loss programs are effective first‐line treatments for obesity and are recommended by the US Preventive Services Task Force. Gaining an understanding of intervention components that are found helpful by different demographic groups can improve tailoring of weight loss programs. This paper examined the perceived helpfulness of different weight loss program components.

Methods

Participants (n = 236) from the active intervention conditions of the Practice‐based Opportunities for Weight Reduction (POWER) Hopkins Trial rated the helpfulness of 15 different components of a multicomponent behavioural weight loss program at 24‐month follow‐up. These ratings were examined in relation to demographic variables, treatment arm and weight loss success.

Results

The components most frequently identified as helpful were individual telephone sessions (88%), tracking weight online (81%) and coach review of tracking (81%). The component least frequently rated as helpful was the primary care providers' general involvement (50%). Groups such as older adults, Blacks and those with lower education levels more frequently reported intervention components as helpful compared with their counterparts.

Discussion

Weight loss coaching delivered telephonically with web support was well received. Findings support the use of remote behavioural interventions for a wide variety of individuals.

Patient-reported outcomes in the practice-based opportunities for weight reduction (POWER) trial

PURPOSE

To evaluate effects of two behavioral weight-loss interventions (in-person, remote) on health-related quality of life (HRQOL) compared to a control intervention.

METHODS

Four hundred and fifty-one obese US adults with at least one cardiovascular risk factor completed five measures of HRQOL and depression: MOS SF-12 physical component summary (PCS) and mental component summary; EuroQoL-5 dimensions single index and visual analog scale; PHQ-8 depression symptoms; and PSQI sleep quality scores at baseline and 6 and 24 months after randomization. Change in each outcome was analyzed using outcome-specific mixed-effects models controlling for participant demographic characteristics.

RESULTS

PCS-12 scores over 24 months improved more among participants in the in-person active intervention arm than among control arm participants (P < 0.05, ES = 0.21); there were no other statistically significant treatment arm differences in HRQOL change. Greater weight loss was associated with improvements in most outcomes (P < 0.05 to < 0.0001).

CONCLUSIONS

Participants in the in-person active intervention improved more in physical function HRQOL than participants in the control arm did. Greater weight loss during the study was associated with greater improvement in all PRO except for sleep quality, suggesting that weight loss is a key factor in improving HRQOL.

Branched-chain amino acid levels are associated with improvement in insulin resistance with weight loss

AIMS/HYPOTHESIS

Insulin resistance (IR) improves with weight loss, but this response is heterogeneous. We hypothesised that metabolomic profiling would identify biomarkers predicting changes in IR with weight loss.

METHODS

Targeted mass spectrometry-based profiling of 60 metabolites, plus biochemical assays of NEFA, β-hydroxybutyrate, ketones, insulin and glucose were performed in baseline and 6 month plasma samples from 500 participants who had lost ≥4 kg during Phase I of the Weight Loss Maintenance (WLM) trial. Homeostatic model assessment of insulin resistance (HOMA-IR) and change in HOMA-IR with weight loss (∆HOMA-IR) were calculated. Principal components analysis (PCA) and mixed models adjusted for race, sex, baseline weight, and amount of weight loss were used; findings were validated in an independent cohort of patients (n = 22).

RESULTS

Mean weight loss was 8.67 ± 4.28 kg; mean ∆HOMA-IR was -0.80 ± 1.73, range -28.9 to 4.82). Baseline PCA-derived factor 3 (branched chain amino acids [BCAAs] and associated catabolites) correlated with baseline HOMA-IR (r = 0.50, p < 0.0001) and independently associated with ∆HOMA-IR (p < 0.0001). ∆HOMA-IR increased in a linear fashion with increasing baseline factor 3 quartiles. Amount of weight loss was only modestly correlated with ∆HOMA-IR (r = 0.24). These findings were validated in the independent cohort, with a factor composed of BCAAs and related metabolites predicting ∆HOMA-IR (p = 0.007).

CONCLUSIONS/INTERPRETATION

A cluster of metabolites comprising BCAAs and related analytes predicts improvement in HOMA-IR independent of the amount of weight lost. These results may help identify individuals most likely to benefit from moderate weight loss and elucidate novel mechanisms of IR in obesity.

Modulation of the BP response to diet by genes in the renin-angiotensin system and the adrenergic nervous system

BACKGROUND

Essential hypertension results from the interaction of several genetic and environmental factors. Identification of genetic factors that modulate blood pressure (BP) response to interventions can lead to improved strategies for prevention and control. The purpose of this study was to identify genes that modulate BP response to dietary interventions.

METHODS

We used data and samples collected in two randomized feeding studies to determine the extent to which genetic architecture is associated with the effect on BP of sodium intake and the Dietary Approaches to Stop Hypertension (DASH) dietary pattern. Participants in both trials were adults with above-optimal BP or unmedicated stage 1 hypertension. Genomic DNA was typed for several candidate genes.

RESULTS

The effect of sodium intake on BP differed by genotype at the angiotensinogen, β2-adrenergic receptor, and kallikrein loci. The effect of DASH dietary pattern on BP differed by genotype at the β2-adrenergic receptor locus.

CONCLUSIONS

These findings have implications for understanding the mechanism(s) through which diet affects BP, the heterogeneity of these effects, and the extent to which dietary interventions can modulate genetic predisposition.

A behavioral weight-loss intervention for persons with serious mental illness in psychiatric rehabilitation centers

Objective

Overweight and obesity are epidemic in populations with serious mental illnesses. We developed and pilot tested a behavioral weight loss intervention appropriately tailored for persons with serious mental disorders.

Methods

We conducted a single arm pilot study in two psychiatric rehabilitation day programs in Maryland and enrolled 63 overweight or obese adults. The six-month intervention provided group and individual weight management and group physical activity classes. The primary outcome was weight change from baseline to 6 months.

Results

Sixty-four percent of those potentially eligible at the centers enrolled. The mean age was 43.7 years; 56% were women, 49% were white and over half had a schizophrenia or schizoaffective disorder. One third had hypertension and one fifth had diabetes. Fifty-two (82%) completed the study; others were discharged from psychiatric centers before study completion. Average attendance across all weight management sessions was 70% (87% on days participants attended the center) and 59% for physical activity classes (74% on days participants attended the center). From a baseline mean of 210.9 lbs (SD 43.9), average weight loss for 52 participants was 4.5 pounds (SD 12.8) (p<0.014). On average, participants lost 1.9% of body weight. Mean waist circumference change was 3.1 cm (SD 5.6). Participants on average increased the distance on the six minute walk test by eight percent.

Conclusion

This pilot documents the feasibility and preliminary efficacy of a behavioral weight loss intervention in adults with serious mental illness who were attendees at psychiatric rehabilitation centers. The results may have implications for developing weight loss interventions in other institutional settings such as schools or nursing homes.

Correlates of N-terminal prohormone brain natriuretic peptides in African Americans with hypertensive chronic kidney disease: the African American Study of Kidney Disease and Hypertension

BACKGROUND/AIMS

The N-amino-terminal fragment of the prohormone B-type natriuretic peptide (NT-proBNP) is a marker of cardiac stress and elevated levels are indicative of heart failure. Few correlates of NT-proBNP levels have been identified in persons with moderate chronic kidney disease (CKD), and data from those without heart failure and from African Americans are especially limited.

METHODS

The African American Study of Kidney Disease and Hypertension (AASK) enrolled nondiabetic African Americans with hypertensive kidney disease (glomerular filtration rate [GFR] = 20-65 ml/min/1.73 m(2)) and no evidence of clinical heart failure. NT-proBNP was measured in 982 AASK participants.

RESULTS

In unadjusted analyses, GFR (r = -0.39; p < 0.001), hematocrit (r = -0.21; p < 0.001) and body mass index (BMI; r = -0.07; p = 0.04) were inversely correlated, and systolic blood pressure (r = 0.30; p < 0.001) and log UPCR (r = 0.32; p < 0.001) were positively correlated with log NT-proBNP levels. After adjustment for potential confounders, lower GFR and hematocrit and higher systolic blood pressure and protein:creatinine ratio remained significantly associated with higher NT-proBNP.

CONCLUSION

Lower GFR and hematocrit, and higher urinary protein excretion may be associated with volume expansion in CKD. These results suggest that these processes are associated with increased NT-proBNP in CKD and may play a role in the development of heart failure.

The relationship between dietary protein intake and blood pressure: results from the PREMIER study

Observational and clinical studies suggest that high protein intake, particularly protein from plant sources, might reduce blood pressure (BP). To examine the association of dietary protein with BP, we analysed data from PREMIER, an 18-month clinical trial (n=810) that examined the effects of two multi-component lifestyle modifications on BP. We examined the association of protein intake with BP, and in particular the independent relationship of plant and animal protein with BP. Multivariable linear regression analyses were performed with both cross-sectional and longitudinal data. Dietary plant protein was inversely associated with both systolic and diastolic BP in cross-sectional analyses at the 6-month follow-up (P=0.0045 and 0.0096, respectively). Fruit and vegetable intake was also inversely associated with both systolic and diastolic BP cross-sectionally at 6 months (P=0.0003 and 0.0157, respectively). In longitudinal analyses, a high intake of plant protein at 6 months was marginally associated with a reduction of both systolic and diastolic BP from baseline to 6 months only (P=0.0797 and 0.0866, respectively), independent of change in body weight and waist circumference. Furthermore, increased intake of plant protein, and fruits and vegetables was significantly associated with a lower risk of hypertension at 6 but not at 18 months. Results of this study indicate that plant protein had a beneficial effect on BP and was associated with a lower risk of hypertension at 6 months. Our data, in conjunction with other research, suggest that an increased intake of plant protein may be useful as a means to prevent and treat hypertension.

N-terminal prohormone brain natriuretic peptide as a predictor of cardiovascular disease and mortality in blacks with hypertensive kidney disease: the African American Study of Kidney Disease and Hypertension (AASK)

BACKGROUND

Higher levels of N-terminal prohormone brain-type natriuretic peptide (NT-proBNP) predict cardiovascular disease (CVD) in several disease states, but few data are available in patients with chronic kidney disease or in blacks.

METHODS AND RESULTS

The African American Study of Kidney Disease and Hypertension trial enrolled hypertensive blacks with a glomerular filtration rate of 20 to 65 mL x min(-1) x 1.73 m(-2) and no other identified cause of kidney disease. NT-proBNP was measured with a sandwich chemiluminescence immunoassay (coefficient of variation 2.9%) in 994 African American Study of Kidney Disease and Hypertension participants. NT-proBNP was categorized as undetectable, low, moderate, or high. Proteinuria was defined as 24-hour urinary protein-creatinine ratio >0.22. A total of 134 first CVD events (CVD death or hospitalization for coronary artery disease, heart failure, or stroke) occurred over a median of 4.3 years. Participants with high NT-proBNP were much more likely to have a CVD event than participants with undetectable NT-proBNP after adjustment (relative hazard 4.0 [95% confidence interval [CI] 2.1 to 7.6]). A doubling of NT-proBNP was associated with a relative hazard of 1.3 (95% CI 1.0 to 1.6) for coronary artery disease, 1.7 (95% CI 1.4 to 2.2) for heart failure, 1.1 (95% CI 0.9 to 1.4) for stroke, and 1.8 (95% CI 1.4 to 2.4) for CVD death. The association of NT-proBNP with CVD events was significantly stronger (P(interaction)=0.05) in participants with than in those without proteinuria. Higher NT-proBNP was not associated with renal disease progression.

CONCLUSIONS

These results suggest that elevated NT-proBNP levels are associated with higher CVD risk among blacks with hypertensive kidney disease. This association may be stronger in individuals with significant proteinuria.

One year follow-up of overweight and obese hypertensive adults following intensive lifestyle therapy

OBJECTIVE

To examine the long-term effect on weight maintenance and dietary habits of participants in a clinical trial for weight loss.

SETTING

Community-based residents living in Maryland.

PARTICIPANTS

Forty-four hypertensive, overweight adults who participated in a randomized clinical trial of weight loss. Participants were randomized to an intensive 'lifestyle' intervention or a 'monitoring' group.

MAIN OUTCOME MEASURES

Weight, self-reported current intake of fat and fruit/fibre and self-reported barriers to maintain weight loss were assessed 1 year after the completion of the Diet, Exercise and Weight-loss Intervention Trial (DEW-IT) trial.

ANALYSIS

t-tests were used to compare groups for differences in continuous variables and chi-square tests were used to compare groups for categorical variables.

RESULTS

Fourty-two of the 44 DEW-IT subjects participated in the follow-up study. Overall, 55% (12/19) of the lifestyle intervention group remained at or below their baseline weight at 1 year, compared with 48% (11/23) of the monitoring group (P = 0.32). However, during that year, 95% (18/19) of the lifestyle intervention group and 52% (12/23) of the monitoring group gained weight from the end of the study. Both groups reported similar intake of fruits/vegetables (servings day(-1)), dietary fibre (g day(-1)) and fat (g day(-1)).

CONCLUSIONS AND IMPLICATIONS

The majority of participants who lost weight during the trial regained weight during the course of 1 year. A successful intensive 2-month programme of lifestyle modification (DEW-IT) was ineffective for long-term maintenance of weight loss.

Effect of lifestyle modifications on blood pressure by race, sex, hypertension status, and age

Recommendations for control of high blood pressure (BP) emphasize lifestyle modification, including weight loss, reduced sodium intake, increased physical activity, and limited alcohol consumption. The Dietary Approaches to Stop Hypertension (DASH) dietary pattern also lowers BP. The PREMIER randomized trial tested multicomponent lifestyle interventions on BP in demographic and clinical subgroups. Participants with above-optimal BP through stage 1 hypertension were randomized to an Advice Only group or one of two behavioural interventions that implement established recommendations (Est) or established recommendations plus DASH diet (Est plus DASH). The primary outcome was change in systolic BP at 6 months. The study population was 810 individuals with an average age of 50 years, 62% women, 34% African American (AA), 95% overweight/obese, and 38% hypertensive. Participants in all the three groups made lifestyle changes. Mean net reductions in systolic (S) BP in the Est intervention were 1.2 mmHg in AA women, 6.0 in AA men, 4.5 in non-AA women, and 4.2 in non-AA men. The mean effects of the Est Plus DASH intervention were 2.1, 4.6, 4.2, and 5.7 mmHg in the four race-sex subgroups, respectively. BP changes were consistently greater in hypertensives than in nonhypertensives, although interaction tests were nonsignificant. The Est intervention caused statistically significant BP reductions in individuals over and under age 50. The Est Plus DASH intervention lowered BP in both age groups, and significantly more so in older individuals. In conclusion, diverse groups of people can adopt multiple lifestyle changes that can lead to improved BP control and reduced CVD risk.

Comparing office-based and ambulatory blood pressure monitoring in clinical trials

Ambulatory blood pressure monitoring (ABPM) is commonly used in clinical trials. Yet, its ability to detect blood pressure (BP) change in comparison to multiple office-based measurements has received limited attention. We recorded ambulatory and five daily pairs of random zero (RZ) BPs pre- and post-intervention on 321 adult participants in the multicentre Dietary Approaches to Stop Hypertension trial. Treatment effect estimates measured by ambulatory monitoring were similar to those measured by RZ and did not differ significantly for waking vs 24-h ambulatory measurements. For systolic BP, the standard deviations of change in mean 24-h ambulatory BP (8.0 mmHg among hypertensives and 6.0 mmHg among nonhypertensives) were comparable to or lower than the corresponding standard deviations of change in RZ-BP based on five daily readings (8.9 and 5.9 mmHg). The standard deviations of change for mean waking ambulatory BP (8.7 and 6.7 mmHg) were comparable to those obtained using three to four daily RZ readings. Results for diastolic BP were qualitatively similar. Ambulatory monitoring was more efficient (ie, a smaller sample size could detect a given BP change) than three to four sets of daily RZ readings and required fewer clinic visits. The average of 33 ambulatory BP readings during the waking hours had an efficiency comparable to that from the mean of four daily pairs of RZ-BPs. Participants readily accepted the ABPM devices, and their use requires less staff training. ABPM provides a useful alternative to RZ-BP measurements in clinical trials.

The impact of angiotensin II receptor blockade and the DASH diet on markers of endogenous fibrinolysis

Hypertension is associated with impaired fibrinolysis. Both angiotensin receptor blockers (ARB) and the DASH (Dietary Approaches to Stop Hypertension) diet effectively lower blood pressure in hypertensive patients. Some evidence suggests that treatment with ARBs could increase fibrinolysis, however, data is conflicting. The impact of the DASH diet on fibrinolytic parameters is not known. Fifty-five hypertensive participants (35 African-American, 20 white) were randomly assigned to receive 8 weeks of either a control diet or the DASH diet. The diets did not differ in sodium content (approximately 3 g/day). Within each diet, individuals were randomly assigned to receive losartan or placebo for 4 weeks in double-blind, cross-over fashion. Tissue plasminogen activator (t-PA) antigen, t-PA activity, plasminogen activator inhibitor-1 (PAI-1) activity and plasma renin activity (PRA) were measured at the end of a 2-week run-in period on the control diet and after each treatment period. The DASH diet did not affect markers of fibrinolysis. Losartan significantly lowered t-PA antigen levels (-1.8 ng/mL, P = 0.045), but had no effect on t-PA or PAI-1 activities. This effect was more pronounced in whites (-4.1 ng/mL (P = 0.003)) compared with African-Americans (-0.3 ng/mL (P = 0.7), P-interaction = 0.03). Results were not materially affected by adjustment for basline values or changes in blood pressure. This study demonstrates that losartan reduces t-PA antigen levels in white, but not African-American hypertensive individuals. In contrast, the DASH diet had no significant effect on markers of fibrinolysis in whites or African-Americans.

Effects of diet and sodium intake on blood pressure: subgroup analysis of the DASH-sodium trial

BACKGROUND

Initial findings from the Dietary Approaches to Stop Hypertension (DASH)-Sodium Trial demonstrated that reduction of sodium intake in two different diets decreased blood pressure in participants with and without hypertension.

OBJECTIVE

To determine effects on blood pressure of reduced sodium intake and the DASH diet in additional subgroups.

DESIGN

Randomized feeding study.

SETTING

Four clinical centers and a coordinating center.

PARTICIPANTS

412 adults with untreated systolic blood pressure of 120 to 160 mm Hg and diastolic blood pressure of 80 to 95 mm Hg.

INTERVENTION

Participants followed the DASH diet or a control (typical U.S.) diet for three consecutive 30-day feeding periods, during which sodium intake (50, 100, and 150 mmol/d at 2100 kcal) varied according to a randomly assigned sequence. Body weight was maintained.

MEASUREMENTS

Systolic and diastolic blood pressure.

RESULTS

In all subgroups, the DASH diet and reduced sodium intake were each associated with significant decreases in blood pressure; these two factors combined produced the greatest reductions. Among nonhypertensive participants who received the control diet, lower (vs. higher) sodium intake decreased blood pressure by 7.0/3.8 mm Hg in those older than 45 years of age (P < 0.001) and by 3.7/1.5 mm Hg in those 45 years of age or younger (P < 0.05).

CONCLUSION

The DASH diet plus reduced sodium intake is recommended to control blood pressure in diverse subgroups.

Cardiovascular risk factors in normotensive and hypertensive Egyptians

OBJECTIVES

To define the prevalence of cardiovascular risk factors and their relation to the level of blood pressure, in Egyptians.

METHODS

Data were collected during the Egyptian National Hypertension project, a national hypertension survey in Egypt. During phase I of the survey, hypertensive (HT) patients were identified. In phase II, clinical and laboratory evaluations were made on HT and gender-matched normotensives (NT). A total of 2313 individuals were examined, 311 NT males, 443 NT females, 670 HT males and 889 HT females.

RESULTS

The prevalence of obesity was 33 and 47% in hypertensive men and women, respectively. After adjusting for age, HT men had significantly higher heart rate, total cholesterol (TC), triglycerides (TG), fasting blood sugar (FBS), post-prandial blood sugar (PBS), body mass index and waist/hip (W/H) ratio than their NT counterparts. In addition, HT women had higher low-density lipoprotein cholesterol (LDL-C). The prevalence of elevated LDL-C and FBS increased with age. The prevalence of hypertriglyceridemia, elevated FBS and obesity rose with increasing level of blood pressure (BP). From the 25-34 to the 55-64 age group, the percentage of hypertensives with > or = 2 risk factors rose from 42.9 to 60.6% in men, and from 9.4 to 46.2% in women. All risk factors were more prevalent in urban populations.

CONCLUSION

This is one of the few reports on the prevalence of cardiovascular risk factors in a developing country. Risk factors cluster with rising level of BP and with ageing. Obesity is very prevalent, particularly in hypertensive Egyptian women. Health efforts directed at the prevention and treatment of obesity should be a high priority.

Angiotensinogen genotype and blood pressure response in the Dietary Approaches to Stop Hypertension (DASH) study

OBJECTIVE

To determine the relationship between angiotensinogen (ANG) genotype and blood pressure response to the dietary patterns of the Dietary Approaches to Stop Hypertension (DASH) trial. The angiotensin converting enzyme (ACE) gene was also tested.

DESIGN

The DASH trial was a randomized outpatient feeding study comparing the effects on blood pressure (BP) of three dietary patterns: a control diet, similar to typical American intake; a 'fruits and vegetables' diet (F/V) that is rich in fruits and vegetables but otherwise resembles the control diet; and the DASH diet that is reduced in fats and that emphasizes fruits, vegetables and low-fat dairy products. Participants' genotype was also determined.

SETTING

Four clinical sites.

PARTICIPANTS

Adults with above-optimal BP or stage 1 hypertension.

INTERVENTION

Participants ate one of the three dietary patterns for 8 weeks. Sodium intake and weight were held constant. In 355 of 459 DASH participants, DNA was extracted from leukocytes and genotyped for the G-6A ANG polymorphism and the D/I ACE polymorphism, by the polymerase chain reaction.

MAIN OUTCOMES

Genotype at ANG and ACE loci; BP after 8 weeks of intervention diet.

RESULTS

There was no association between ACE genotype and BP response. Associations with ANG polymorphism were significant: net systolic and diastolic BP response to the DASH diet was greatest in individuals with the AA genotype (-6.93/-3.68 mmHg) and least in those with the GG genotype (-2.80/0.20 mmHg). A similar relationship existed for the F/V diet.

CONCLUSIONS

ANG genotype is associated with BP response to the DASH diet. The AA genotype confers excess risk of hypertension and is associated with increased responsiveness to diet.

Relationship between systemic markers of inflammation and serum beta-carotene levels

BACKGROUND

Low serum levels of beta-carotene have been associated with increased risk of cancer and cardiovascular disease. However, in clinical trials, supplementation of the diet with beta-carotene either had no benefit or caused harm. This pattern of findings raises the possibility that confounding by other factors might explain the association between serum beta-carotene level and disease risk.

METHODS

We used data from 14 470 current smokers, ex-smokers, and never smokers aged 18 years or older who participated in the Third National Health and Nutrition Examination Survey to assess the relationship between serum beta-carotene and markers of inflammation (C-reactive protein and white blood cell count).

RESULTS

After adjustment for beta-carotene intake and other factors, geometric mean levels of serum beta-carotene for individuals with undetectable (< 0.22 mg/dL), mildly elevated (0.22-0.99 mg/dL), and clinically elevated (> or =1.0 mg/dL) C-reactive protein levels were 18.0, 16.1, and 13.6 microg/dL, respectively, in never smokers; 18.1, 15.7, and 13.9 microg/dL in ex-smokers; and 11.3, 10.2, and 9.4 microg/dL in current smokers (P< .001 for all). In corresponding analyses, white blood cell count was also inversely related to serum beta-carotene concentration (P< .05 for all).

CONCLUSIONS

The strong and inverse association of serum beta-carotene level with C-reactive protein level and white blood cell count suggests that the relationship between serum beta-carotene concentration and disease risk might be confounded by inflammation. More broadly, for beta-carotene and likely other nutrients, it seems unwise to interpret biomarker data as prima facie evidence of dietary intake without a more complete understanding of the physiologic processes that affect nutrient levels.

Motivations for exercise and weight loss among African-American women: focus group results and their contribution towards program development

OBJECTIVE

African-American women are more likely to be sedentary and maintain higher body weights compared with Caucasian women, although some are physically active and able to maintain weight loss. To develop effective intervention strategies, we need to understand why some women are successful.

DESIGN

We conducted focus groups on four distinct groups of African-American women (currently physically active; currently sedentary; successful weight loss for > or = 1 year; unsuccessful weight loss) to explore motivations and intervention strategies. Open-ended questions, probes, and visual aids were used to stimulate discussions. Transcripts of sessions were read to highlight themes and concepts.

RESULTS

Results indicated that motivators for the exercisers to start exercising were health concerns, weight control, stress reduction, and the influence of others. Motivators to continue exercising were feeling good and having energy. In contrast, the sedentary women reported that social support and enjoyment would be motivating. Both groups reported that physically active women conveyed the image of high energy and self-esteem. The successful weight loss women employed strategies that allowed them to eat a variety of foods and were less likely to 'diet'. The unsuccessful women referred to 'going on a diet' and were more likely to label foods as 'good' or 'bad'. They reported feeling tired and thought that losing weight would give them more energy.

CONCLUSION

This information was used to develop two culturally appropriate interventions for African-American women, which is presented. Conducting formative research in study design protocols can provide an important role in intervention development.

A comparison of the Yale Physical Activity Survey with other physical activity measures

PURPOSE

The purpose of this study was to determine associations of the Yale Physical Activity Survey (YPAS) with the Stanford 7-d physical activity recall (PAR) and several physiologic measures, both cross-sectionally and longitudinally.

METHODS

Participants were 59 individuals (45% African-American, 79% women) between the ages of 60 and 80 yr who were enrolled in a clinical trial. From the YPAS, total time in activity, estimated weekly energy expenditure, and indices of vigorous activity, leisurely walking, moving, standing, sitting, and an overall summary index were determined. From the PAR, daily energy expenditure, and hours spent in light, moderate, and hard/very hard activities were estimated. Physiologic measurements included estimated VO2max, resting pulse rate, and body mass index (BMI).

RESULTS

Weekly energy expenditure, total time in activity, and the summary index correlated with daily energy expenditure at baseline (Spearman correlations = 0.37, 0.30, 0.33, respectively, Ps < 0.01) and time in moderate activity (r = 0.37, 0.29, 0.39, Ps < 0.01). The vigorous index was also significantly correlated with daily energy expenditure and time in light, moderate, and hard/very hard activity. The summary, moving, and standing indices correlated with VO2max (Ps < 0.05) and BMI (Ps < 0.05). Change in physical activity determined from the PAR correlated with change in most YPAS dimensions, although few correlations were statistically significant.

CONCLUSIONS

The global activities and the vigorous activity index determined from the YPAS correlated with corresponding measures of the PAR. The validity of the YPAS for light-intensity activities is less clear, although optimal validation measures for light-intensity activity are yet to be defined. The ability of the YPAS to detect change in physical activity shows some promise, but data from this study are insufficient to be conclusive.

Low serum cholesterol and haemorrhagic stroke in men: Korea Medical Insurance Corporation Study

BACKGROUND

In some prospective studies, haemorrhagic stroke occurs more frequently in individuals with low serum cholesterol than in those with higher concentrations. We aimed to determine whether low total serum cholesterol is an independent risk factor for haemorrhagic stroke (intracerebral haemorrhage and subarachnoid haemorrhage) in South Korea, a country that has a population with relatively low concentrations of total serum cholesterol.

METHODS

We measured total serum cholesterol and other cardiovascular risk factors in 114,793 Korean men, aged between 35-59 years in 1990 and 1992, in a prospective observational study. We used data obtained in 1992 for smoking and alcohol consumption. We divided total serum cholesterol into quintiles (<4.31 mmol/L, 4.31-<4.74, 4.74-<5.16, 5.16-<5.69 and > or = 5.69). Our primary outcomes were hospital admissions and deaths from intracerebral and subarachnoid haemorrhage in a 6 year follow-up between 1993 and 1998.

FINDINGS

528 men had a haemorrhagic stroke--372 intracerebral and 98 subarachnoid haemorrhage--and 58 were unspecified strokes. The relative risks of intracerebral haemorrhage in each quintile of total serum cholesterol (lowest to highest were: 1.22 (95% CI 0.88-1.69); 0.86 (0.60-1.21); 1.08 (0.78-1.48); and 1.03 (0.75-1.41). The corresponding relative risks for subarachnoid haemorrhage were: 1.44 (0.76-2.73); 1.13 (0.59-2.20); 1.21 (0.64-2.29); and 1.12 (0.59-2.14).

INTERPRETATION

Low total serum cholesterol is not an independent risk factor for either intracerebral or subarachnoid haemorrhagic stroke in Korean men.

Effects of reduced sodium intake on hypertension control in older individuals: results from the Trial of Nonpharmacologic Interventions in the Elderly (TONE)

BACKGROUND

Few trials have evaluated the effects of reduced sodium intake in older individuals, and no trial has examined the effects in relevant subgroups such as African Americans.

PATIENTS AND METHODS

The effects of sodium reduction on blood pressure (BP) and hypertension control were evaluated in 681 patients with hypertension, aged 60 to 80 years, randomly assigned to a reduced sodium intervention or control group. Participants (47% women, 23% African Americans) had systolic BP less than 145 mm Hg and diastolic BP less than 85 mm Hg while taking 1 antihypertensive medication. Three months after the start of intervention, medication was withdrawn. The primary end point was occurrence of an average systolic BP of 150 mm Hg or more, an average diastolic BP of 90 mm Hg or more, the resumption of medication, or a cardiovascular event during follow-up (mean, 27.8 months).

RESULTS

Compared with control, mean urinary sodium excretion was 40 mmol/d less in the reduced sodium intervention group (P<.001); significant reductions in sodium excretion occurred in subgroups defined by sex, race, age, and obesity. Prior to medication withdrawal, mean reductions in systolic and diastolic BPs from the reduced sodium intervention, net of control, were 4.3 mm Hg (P<.001) and 2.0 mm Hg (P =.001). During follow-up, an end point occurred in 59% of reduced sodium and 73% of control group participants (relative hazard ratio = 0.68, P<.001). In African Americans, the corresponding relative hazard ratio was 0.56 (P =.005); results were similar in other subgroups. In dose-response analyses, end points were progressively less frequent with greater sodium reduction (P for trend =.002).

CONCLUSION

A reduced sodium intake is a broadly effective, nonpharmacologic therapy that can lower BP and control hypertension in older individuals.

Coffee consumption and serum lipids: a meta-analysis of randomized controlled clinical trials

Coffee drinking has been associated with increased serum cholesterol levels in some, but not all, studies. A Medline search of the English-language literature published prior to December 1998, a bibliography review, and consultations with experts were performed to identify 14 published trials of coffee consumption. Information was abstracted independently by two reviewers using a standardized protocol. With a random-effects model, treatment effects were estimated by pooling results from individual trials after weighting the results by the inverse of total variance. A dose-response relation between coffee consumption and both total cholesterol and LDL cholesterol was identified (p < 0.01). Increases in serum lipids were greater in studies of patients with hyperlipidemia and in trials of caffeinated or boiled coffee. Trials using filtered coffee demonstrated very little increase in serum cholesterol. Consumption of unfiltered, but not filtered, coffee increases serum levels of total and LDL cholesterol.

Effects on blood pressure of reduced dietary sodium and the Dietary Approaches to Stop Hypertension (DASH) diet. DASH-Sodium Collaborative Research Group

BACKGROUND

The effect of dietary composition on blood pressure is a subject of public health importance. We studied the effect of different levels of dietary sodium, in conjunction with the Dietary Approaches to Stop Hypertension (DASH) diet, which is rich in vegetables, fruits, and low-fat dairy products, in persons with and in those without hypertension.

METHODS

A total of 412 participants were randomly assigned to eat either a control diet typical of intake in the United States or the DASH diet. Within the assigned diet, participants ate foods with high, intermediate, and low levels of sodium for 30 consecutive days each, in random order.

RESULTS

Reducing the sodium intake from the high to the intermediate level reduced the systolic blood pressure by 2.1 mm Hg (P<0.001) during the control diet and by 1.3 mm Hg (P=0.03) during the DASH diet. Reducing the sodium intake from the intermediate to the low level caused additional reductions of 4.6 mm Hg during the control diet (P<0.001) and 1.7 mm Hg during the DASH diet (P<0.01). The effects of sodium were observed in participants with and in those without hypertension, blacks and those of other races, and women and men. The DASH diet was associated with a significantly lower systolic blood pressure at each sodium level; and the difference was greater with high sodium levels than with low ones. As compared with the control diet with a high sodium level, the DASH diet with a low sodium level led to a mean systolic blood pressure that was 7.1 mm Hg lower in participants without hypertension, and 11.5 mm Hg lower in participants with hypertension.

CONCLUSIONS

The reduction of sodium intake to levels below the current recommendation of 100 mmol per day and the DASH diet both lower blood pressure substantially, with greater effects in combination than singly. Long-term health benefits will depend on the ability of people to make long-lasting dietary changes and the increased availability of lower-sodium foods.

Long-term weight loss and changes in blood pressure: results of the Trials of Hypertension Prevention, phase II

BACKGROUND

Weight loss appears to be an effective method for primary prevention of hypertension. However, the long-term effects of weight loss on blood pressure have not been extensively studied.

OBJECTIVE

To present detailed results from the weight loss arm of Trials of Hypertension Prevention (TOHP) II.

DESIGN

Multicenter, randomized dinical trial testing the efficacy of lifestyle interventions for reducing blood pressure over 3 to 4 years. Participants in TOHP II were randomly assigned to one of four groups. This report focuses only on participants assigned to the weight loss (n = 595) and usual care control (n = 596) groups.

PATIENTS

Men and women 30 to 54 years of age who had nonmedicated diastolic blood pressure of 83 to 89 mm Hg and systolic blood pressure less than 140 mm Hg and were 110% to 165% of their ideal body weight at baseline.

INTERVENTION

The weight loss intervention included a 3-year program of group meetings and individual counseling focused on dietary change, physical activity, and social support

MEASUREMENTS

Weight and blood pressure data were collected every 6 months by staff who were blinded to treatment assignment

RESULTS

Mean weight change from baseline in the intervention group was -4.4 kg at 6 months, -2.0 kg at 18 months, and -0.2 kg at 36 months. Mean weight change in the control group at the same time points was 0.1, 0.7, and 1.8 kg. Blood pressure was significantly lower in the intervention group than in the control group at 6, 18, and 36 months. The risk ratio for hypertension in the intervention group was 0.58 (95% CI, 0.36 to 0.94) at 6 months, 0.78 (CI, 0.62 to 1.00) at 18 months, and 0.81 (CI, 0.70 to 0.95) at 36 months. In subgroup analyses, intervention participants who lost at least 4.5 kg at 6 months and maintained this weight reduction for the next 30 months had the greatest reduction in blood pressure and a relative risk for hypertension of 0.35 (CI, 0.20 to 0.59).

CONCLUSIONS

Clinically significant long-term reductions in blood pressure and reduced risk for hypertension can be achieved with even modest weight loss.

Nutrition-related cardiovascular risk factors in older people: results from the Third National Health and Nutrition Examination Survey

SETTING

In view of the recognized potential benefits of nutritional therapy in older persons, Congress is evaluating the coverage of nutritional services for Medicare beneficiaries.

OBJECTIVE

To estimate the number of older persons in the US who have one or more cardiovascular risk factors (hypertension, increased low density lipoprotein (LDL) cholesterol, and diabetes mellitus), for which nutritional therapy is recommended.

DESIGN

Cross-sectional analysis of adults, aged > or = 65, participating in the Third National Health and Nutrition Examination Survey (NHANES III).

MAIN OUTCOMES

The authors estimated the proportion of adults, aged > or = 65, with diabetes mellitus, increased LDL cholesterol, and/or hypertension. Efforts were made to assess whether obesity status, gender, race, and/or socioeconomic factors were associated with the prevalence of any or all three conditions.

RESULTS

Approximately 86% (20 million persons) in the US, aged > or = 65, have at least one of the index conditions. Whereas a higher body mass index (BMI) increased the likelihood of having any or all three conditions, 81% of persons of average body weight (BMI <25 kg/m2) had at least one condition. After adjusting for age, gender, BMI, marital status, and poverty index, blacks were more likely than whites to have any one condition (odds ratio (OR) = 3.0, P < .01) or all three conditions (OR = 2.3, P = .05).

CONCLUSIONS

Almost 90% of Americans aged > or = 65 have one or more nutrition-related cardiovascular risk factors. Improved nutritional interventions may be valuable especially for blacks, who have a higher prevalence of conditions requiring nutritional therapy.

The role of diet in the prevention and treatment of hypertension

An impressive body of evidence strongly supports the concept that multiple dietary factors influence blood pressure and that modification of diet can have powerful, beneficial effects on this highly prevalent, yet modifiable, cardiovascular risk factor. Dietary therapies with a proven ability to lower blood pressure include reduced sodium intake, weight loss, moderation of alcohol intake, increased potassium intake, and a diet that emphasizes fruits, vegetables, and low-fat dairy products that is low in fat and cholesterol. Several other dietary factors, such as an increased intake of protein or monounsaturated fatty acids, may also reduce blood pressure, but evidence to date is insufficient for policy recommendations. Still, widespread implementation of those therapies with a proven ability to lower blood pressure should have an enormous impact on the adverse patterns of blood pressure that remain highly prevalent in the United States and most other countries.

The methylenetetrahydrofolate reductase gene is associated with increased cardiovascular risk in Japan, but not in other populations

The methylenetetrahydrofolate reductase (MTHFR) gene has been associated with increased risk for cardiovascular disease in some, but not all studies. Our data sources included a MEDLINE search of the literature published before December 1998, a bibliography review, and expert consultation. Of 23 studies initially identified, 18 (9855 persons) met the inclusion criteria. Information on sample size, study design, Hardy-Weinberg equilibrium, method of genotype determination, plasma folate and homocysteine were abstracted by two reviewers using a standardized protocol. The overall odds ratio of the MTHFR gene on cardiovascular disease was estimated using the Mantel-Haenzel method. From 12 studies with angiographically-confirmed coronary artery disease (CAD), the overall odds ratio (OR) for CAD among those with heterozygous (V/A) was 1.3 (95% CI, 1.1-1.5), while it was 1.4 (1.2-1.6) for the homozygous mutant (V/V) compared to those with homozygous normal (A/A). However, the overall odds ratio for CAD among those with the V/V genotype versus A/A genotype was not statistically significant (OR: 1.1; 95% CI: 0.9-1.3) after excluding three Japanese studies. The corresponding OR for the three Japanese studies was 2.0 (1.6-2.7). For six studies with myocardial infarction (MI), the overall OR of MI was 1.0 (0.8-1.1) for those with the V/A genotype and 0.9 (0.7-1.1) for those with the V/V genotype, respectively; none of these ORs for MI was statistically significant. The MTHFR gene is associated with increased risk for CAD in Japan, but not in other populations.

Impact of pill organizers and blister packs on adherence to pill taking in two vitamin supplementation trials

The impact of pill organizers on pill taking was determined in the Trial of Antioxidant Vitamins C and E (TRACE) Study, a factorial trial of vitamin C and vitamin E supplementation in 184 individuals. Participants were recruited in 1996-1997 and randomized to one of two groups (pill organizer or no organizer) and to one of four supplement groups for 2 months. The pill count (observed/expected X 100%) distribution was similar in the organizer and no organizer group for both vitamins. Mean differences in changes in serum vitamin levels between active and placebo groups did not differ by pill organizer use. The impact of pill organizers and blister packs was compared in another trial, the Vitamins, Teachers, and Longevity (VITAL) Study, in 297 individuals randomized in 1993-1994 to receive study pills either in blister packs or in pill organizers and to take one of two supplements. Among those with lower adherence, the pill count distribution in the blister-pack group exceeded that in the organizer group. Mean differences in serum vitamin E levels between active and placebo groups did not differ by types of pill packaging. In summary, use of blister packs, but not pill organizers, improved adherence as measured by pill counts among those with lower adherence. Neither pill delivery system improved adherence as measured by serum vitamin levels.

The effect of dietary patterns on blood pressure control in hypertensive patients: results from the Dietary Approaches to Stop Hypertension (DASH) trial

To determine the impact of dietary patterns on the control of hypertension we studied the subgroup of 133 participants with systolic blood pressure (BP) of 140 to 159 mm Hg and/or diastolic BP of 90 to 95 mm Hg enrolled in the Dietary Approaches to Stop Hypertension (DASH) study. Participants were fed a control diet for a 3-week period and were then randomized to receive for 8 weeks either the control diet; a diet rich in fruits and vegetables, but otherwise similar to control; or a combination diet rich in fruits, vegetables, and low-fat dairy products, including whole grains, fish, poultry, and nuts, and reduced in fats, red meats, sweets, and sugar-containing beverages. Sodium intake and body weight were held constant throughout the study. The combination diet significantly reduced systolic BP (-11.4 mm Hg, P < .001) and diastolic BP (-5.5 mm Hg, P < .001). The fruits-and-vegetables diet also significantly reduced systolic BP (-7.2 mm Hg, P < .001) and diastolic BP (-2.8 mm Hg, P = .013). The combination diet produced significantly greater BP effects (P < .05) than the fruits-and-vegetables diet. Blood pressure changes were evident within 2 weeks of starting the intervention feeding. After the 8-week intervention period, 70% of participants eating the combination diet had a normal BP (systolic BP < 140 and diastolic BP < 90 mm Hg) compared with 45% on the fruits-and-vegetables diet and 23% on the control diet. In patients with hypertension, the DASH combination diet effectively lowers BP and may be useful in achieving control of Stage 1 hypertension.

Effect of dietary patterns on serum homocysteine: results of a randomized, controlled feeding study

BACKGROUND

Elevated blood levels of homocysteine are associated with an increased risk of atherosclerotic cardiovascular disease. Although numerous studies have assessed the impact of vitamin supplements on homocysteine, the effect of dietary patterns on homocysteine has not been well studied.

METHODS AND RESULTS

During a 3-week run-in, 118 participants were fed a control diet, low in fruits, vegetables, and dairy products, with a fat content typical of US consumption. During an 8-week intervention phase, participants were then fed 1 of 3 randomly assigned diets: the control diet, a diet rich in fruits and vegetables but otherwise similar to control, or a combination diet rich in fruits, vegetables, and low-fat dairy products and reduced in saturated and total fat. Between the end of run-in and intervention periods, mean change in homocysteine was +0.46 micromol/L in the control diet, +0.21 micromol/L in the fruits and vegetables diet (P=0.47 compared with control), and -0.34 micromol/L in the combination diet (P=0.03 compared with control, P=0.12 compared with the fruits and vegetables diet). In multivariable regression models, change in homocysteine was significantly and inversely associated with change in serum folate (P=0.03) but not with change in serum vitamin B(12) (P=0.64) or pyridoxal 5' phosphate, the coenzyme form of vitamin B(6) (P=0.83).

CONCLUSIONS

Modification of dietary patterns can have substantial effects on fasting levels of total serum homocysteine. These results provide additional insights into the mechanisms by which diet might influence the occurrence of atherosclerotic cardiovascular disease.

Relationship between skin color and blood pressure in egyptian adults: results from the national hypertension project

In many, but not all societies, dark skin color is associated with high blood pressure. Whether the association between skin color and blood pressure is independent of known determinants of blood pressure remains controversial. We examined the association between skin color and blood pressure in 835 Egyptian adults (370 men and 465 women) participating in the National Hypertension Project, a national survey of hypertension prevalence and blood pressure-related complications conducted in Egypt during 1991-1993. Skin color was assessed by measuring the concentration of cutaneous melanin in an unexposed area with the use of reflectance spectrophotometry. Higher concentrations of melanin were associated with lower body mass index, less education, manual labor (among men), and a lower urinary sodium-to-potassium ratio (among women). In multivariate regression analyses adjusted for age, body mass index, and education, there was a significant nonlinear association between blood pressure and skin color among women; in the lower to intermediate range of skin pigmentation, both systolic and diastolic blood pressures were higher in women with greater concentrations of cutaneous melanin. In men, blood pressure was not associated with skin color. When we used a subjective assessment of skin color, there was no significant difference in blood pressure between black-skinned Egyptians (predominantly of Nubian descent) and fair-skinned Egyptians for either gender. While the significant relationship in women appeared to be independent of known risk factors for hypertension, residual confounding may explain the association.

The effects of vitamin C and vitamin E on oxidative DNA damage: results from a randomized controlled trial

Oxidative DNA damage may be important in mutagenic, carcinogenic, and aging processes. Although it is plausible that antioxidant vitamins may reduce oxidative DNA damage, evidence from human studies has been sparse and inconsistent. We determined the short-term effects of vitamin C (500 mg/day) and vitamin E (400 IU d-alpha-tocopheryl acetate/day) supplements on oxidative DNA damage in a double-masked, placebo-controlled, 2x2 factorial trial in 184 nonsmoking adults. Mean duration of supplementation was 2 months. Oxidative DNA damage was measured by 24-h urinary excretion of 8-hydroxy-2'-deoxyguanosine (8-OHdG). At baseline, urinary 8-OHdG (mean +/- SE; ng/mg creatinine) was associated with race (15.6 +/- 0.8 in African Americans versus 20.3 +/- 1.2 in Caucasians, P = 0.001), prior antioxidant supplement use (18.6 +/- 0.8 in users versus 13.8 +/- 1.5 in non-users, P = 0.007), and regular exercise (19.2 +/- 1.1 in exercisers versus 16.6 +/- 0.9 in non-exercisers, P = 0.04). Fruit and vegetable intake and serum ascorbic acid were inversely associated with urinary 8-OHdG (P-trend = 0.02 and 0.016, respectively). The benefits of fruit and vegetable intake became evident with the consumption being at least three servings/day. At the end of supplementation, change from baseline in urinary 8-OHdG (mean +/- SE; ng/mg creatinine) was -0.6 +/- 1.4 (P = 0.61), 0.6 +/- 1.1 (P = 0.59), 0.5 +/- 1.0 (P = 0.61), and 1.6 +/- 1.4 (P = 0.27) in the placebo, vitamin C alone, vitamin E alone, and combined vitamins C and E groups, respectively. In overall and subgroup analyses, there was no significant main effect or interaction effect of the supplements on urinary 8-OHdG. In conclusion, supplementation of diet with vitamin C (500 mg/day) and vitamin E (400 IU d-alpha-tocopheryl acetate/day) had no significant main effect or interaction effect on oxidative DNA damage as measured by urinary 8-OHdG in nonsmoking adults. However, several aspects of a healthy lifestyle were associated with lower oxidative DNA damage.

Long-term effects of weight loss and dietary sodium reduction on incidence of hypertension

To examine the long-term effects of weight loss and dietary sodium reduction on the incidence of hypertension, we studied 181 men and women who participated in the Trials of Hypertension Prevention, phase 1, in Baltimore, Md. At baseline (1987 to 1988), subjects were 30 to 54 years old and had a diastolic blood pressure (BP) of 80 to 89 mm Hg and systolic BP <160 mm Hg. They were randomly assigned to one of two 18-month lifestyle modification interventions aimed at either weight loss or dietary sodium reduction or to a usual care control group. At the posttrial follow-up (1994 to 1995), BP was measured by blinded observers who used a random-zero sphygmomanometer. Incident hypertension was defined as systolic BP > or =160 mm Hg and/or diastolic BP > or =90 mm Hg and/or treatment with antihypertensive medication during follow-up. Body weight and urinary sodium were not significantly different among the groups at the posttrial follow-up. After 7 years of follow-up, the incidence of hypertension was 18.9% in the weight loss group and 40.5% in its control group and 22.4% in the sodium reduction group and 32.9% in its control group. In logistic regression analysis adjusted for baseline age, gender, race, physical activity, alcohol consumption, education, body weight, systolic BP, and urinary sodium excretion, the odds of hypertension was reduced by 77% (odds ratio 0.23; 95% confidence interval 0.07 to 0.76; P=0.02) in the weight loss group and by 35% (odds ratio 0.65; 95% confidence interval 0.25 to 1.69; P=0.37) in the sodium reduction group compared with their control groups. These results indicate that lifestyle modification such as weight loss may be effective in long-term primary prevention of hypertension.

Smoking and atherosclerotic cardiovascular disease in men with low levels of serum cholesterol: the Korea Medical Insurance Corporation Study

CONTEXT

Few studies have examined the interactive effects of smoking and serum cholesterol level on morbidity and mortality from cardiovascular dieseases. In East Asia, where the prevalence of smoking is among the highest in the world, morbidity and mortality from ischemic heart disease (IHD) is rapidly escalating.

OBJECTIVES

To determine whether cigarette smoking is an independent risk factor for atherosclerotic cardiovascular disease (ASCVD) in the Republic of Korea (South Korea), a population that has relatively low levels of serum cholesterol, and to determine whether serum cholesterol levels modify the risk relationship between smoking and ASCVD.

DESIGN

Prospective cohort study with a follow-up period of 6 years (1993-1998).

SETTING AND SUBJECTS

A total of 106745 Korean men aged 35 to 59 years who received health insurance from the Korea Medical Insurance Corporation and who had biennial medical evaluations in 1990 and 1992.

MAIN OUTCOME MEASURES

Hospital admissions and deaths from IHD, cerebrovascular disease (CVD), and total ASCVD.

RESULTS

At baseline, 61389 (58%) were current cigarette smokers and 64482 (60%) had a total cholesterol level of less than 5.17 mmol/L (200 mg/dL). Between 1993 and 1998, 1006 IHD events (176 per 100000 person-years), 1364 CVD events (238 per 100000 person-years), and 716 other ASCVD events (125 per 100000 person-years) occurred. In multivariate Cox proportional hazard models controlling for age, hypertension, hypercholesterolemia, and diabetes, current smoking increased the risk of IHD (risk ratio [RR], 2.2; 95% confidence interval [CI], 1.8-2.8), CVD (RR, 1.6; 95% CI, 1.4-1.8), and total ASCVD (RR, 1.6; 95% CI, 1.5-1.8). For each outcome, there were significant dose-response relationships with amount and duration of smoking. Throughout the range of serum cholesterol levels, current smoking significantly increased the risk of IHD and CVD. In the lowest quartile of serum cholesterol levels (<4.42 mmol/L [171 mg/dL]), the RR from current smoking was 3.3 (95% CI, 1.7-6.2) for IHD and 1.6 (95% CI, 1.2-2.3) for CVD. There was no evidence of an interaction between smoking and serum cholesterol (P for interaction = .75, .87, and .92 for IHD, CVD, and total ASCVD, respectively).

CONCLUSIONS

This study demonstrates that in Korea smoking is a major independent risk factor for IHD, CVD, and ASCVD and that a low cholesterol level confers no protective benefit against smoking-related ASCVD.

Effect of dietary patterns on ambulatory blood pressure : results from the Dietary Approaches to Stop Hypertension (DASH) Trial. DASH Collaborative Research Group

We measured ambulatory blood pressure (ABP) in 354 participants in the Dietary Approaches to Stop Hypertension (DASH) Trial to determine the effect of dietary treatment on ABP (24-hour, day and night) and to assess participants' acceptance of and compliance with the ABP monitoring (ABPM) technique. After a 3-week run-in period on a control "typical" American diet, subjects (diastolic blood pressure [BP], 80 to 95 mm Hg; systolic BP, <160 mm Hg; mean age, 45 years) were randomly assigned to 1 of 3 diets for an 8-week intervention period: a continuation of the control diet; a diet rich in fruits and vegetables; and a "combination" diet that emphasized fruits, vegetables, and low-fat dairy products. We measured ABP at the end of the run-in and intervention periods. Both the fruit/vegetable and combination diets lowered 24-hour ABP significantly compared with the control diet (P<0. 0001 for systolic and diastolic pressures on both diets: control diet, -0.2/+0.1 mm Hg; fruit/vegetable diet, -3.2/-1.9 mm Hg; combination diet, -4.6/-2. 6 mm Hg). The combination diet lowered pressure during both day and night. Hypertensive subjects had a significantly greater response than normotensives to the combination diet (24-hour ABP, -10.1/-5.5 versus -2.3/-1.6 mm Hg, respectively). After correction for the control diet responses, the magnitude of BP lowering was not significantly different whether measured by ABPM or random-zero sphygmomanometry. Participant acceptance of ABPM was excellent: only 1 participant refused to wear the ABP monitor, and 7 subjects (2%) provided incomplete recordings. These results demonstrate that the DASH combination diet provides significant round-the-clock reduction in BP, especially in hypertensive participants.