Geographic Information Systems to Assess External Validity in Randomized Trials.

INTRODUCTION: To support claims that RCTs can reduce health disparities (i.e., are translational), it is imperative that methodologies exist to evaluate the tenability of external validity in RCTs when probabilistic sampling of participants is not employed. Typically, attempts at establishing post hoc external validity are limited to a few comparisons across convenience variables, which must be available in both sample and population. A Type 2 diabetes RCT was used as an example of a method that uses a geographic information system to assess external validity in the absence of a priori probabilistic community-wide diabetes risk sampling strategy. METHODS: A geographic information system, 2009-2013 county death certificate records, and 2013-2014 electronic medical records were used to identify community-wide diabetes prevalence. Color-coded diabetes density maps provided visual representation of these densities. Chi-square goodness of fit statistic/analysis tested the degree to which distribution of RCT participants varied across density classes compared to what would be expected, given simple random sampling of the county population. Analyses were conducted in 2016. RESULTS: Diabetes prevalence areas as represented by death certificate and electronic medical records were distributed similarly. The simple random sample model was not a good fit for death certificate record (chi-square, 17.63; p=0.0001) and electronic medical record data (chi-square, 28.92; p<0.0001). Generally, RCT participants were oversampled in high-diabetes density areas. CONCLUSIONS: Location is a highly reliable "principal variable" associated with health disparities. It serves as a directly measurable proxy for high-risk underserved communities, thus offering an effective and practical approach for examining external validity of RCTs.

The Lifestyle Intervention for the Treatment of Diabetes study (LIFT Diabetes): Design and baseline characteristics for a randomized translational trial to improve control of cardiovascular disease risk factors.

The prevalence of type 2 diabetes continues to increase in minority and underserved patients, who are also more likely to have poorer control of diabetes and related risk factors for complications. Although the Look AHEAD trial has demonstrated improved risk factor control among overweight or obese diabetes patients who received an intensive lifestyle intervention, translating such findings into accessible programs is a major public health challenge. The purpose of this paper is to report the design and baseline characteristics of the Lifestyle Interventions for the Treatment of Diabetes study (LIFT Diabetes). The overall goal is to test the impact of a community-based lifestyle weight loss (LWL) intervention adapted from Look AHEAD on cardiovascular disease risk at 12-months and 24-months among minority and lower income diabetes patients. Secondary outcomes include body weight, physical activity, medication use, cost, resource utilization, and safety. The primary hypothesis being tested is that the LWL will result in 10% relative reduction in CVD risk compared to the DSM. We have randomized 260 overweight or obese adults with diabetes one of two 12-month interventions: a LWL condition delivered by community health workers or a diabetes self-management (DSM) education condition. The baseline demographic characteristics indicate that our sample is predominantly female, obese, low income, and ethnic minority. Translating evidence-based, lifestyle strategies, and targeting minority and underserved patients, will yield, if successful, a model for addressing the burden of diabetes and may favorably impact health disparities.

The use of electronic medical records for recruitment in clinical trials: findings from the Lifestyle Intervention for Treatment of Diabetes trial.

BACKGROUND: The use of the electronic medical record (EMR) system in recruitment in clinical trials has the potential for providing a very reliable and cost-effective recruiting methodology which may improve participant recruitment in clinical trials. We examined a recruitment approach centered on the use of the EMR, as well as other traditional methods, in the Lifestyle Intervention for Treatment of Diabetes (LIFT Diabetes) trial. METHODS: LIFT Diabetes is a randomized controlled trial designed to investigate the effects of two contrasting interventions on cardiovascular disease risk: a community-based intensive lifestyle program aimed at achieving weight loss and a clinic-based enhanced diabetes self-management program. Eligible participants were overweight/obese (body mass index, BMI ≥25 kg/m2) patients with type 2 diabetes who were aged 21 years or older. Recruitment strategies included the use of the EMR system (primary), direct referrals, media advertisements, and community screenings. RESULTS: A total of 1102 telephone screens were conducted, resulting in randomization of 260 participants (61.5 % from EMR, mean age 56.3 years, 66.2 % women, 48.1 % non-Hispanic blacks) over a 21-month period, with a yield of 23.6 %. Recruitment yields differed by recruitment method, with referrals having the highest yield (27.5 %). A history of cardiovascular disease was the main health reason for exclusion from the study (16.5 %). An additional 8.9 % were excluded for BMI <25 kg/m2 (<27 kg/m2 for insulin users), 5.4 % could not exercise, 5.2 % had an HbA1c >11 %, and 34.9 % were excluded for other non-medical reasons. Exclusion criteria did not appear to differentially affect enrollment in terms of race or ethnicity. CONCLUSIONS: Future clinical studies should tailor their recruitment strategies based on the participant demographics of interest. Efficient methods such as using the EMR system and referrals should be prioritized over labor-intensive, low-yielding methods such as community screenings and mass mailings. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01806727 . Registered on 5 March 2013.

Ethnic variation in oral health and social integration among older rural adults.

This analysis examines the associations of oral health with social integration among ethnically diverse (African American, American Indian, White) rural older adults. Data are from a cross-sectional survey of 635 randomly selected community-dwelling adults aged 60+. Measures include self-rated oral health, number of teeth, number of oral health problems, social engagement, and social network size. Minority elders have poorer oral health than do White older adults. Most rural elders have substantial social engagement and social networks. Better oral health (greater number of teeth) is directly associated with social engagement, whereas the relationship of oral health to social network size is complex. The association of oral health with social engagement does not differ by ethnicity. Poorer oral health is associated with less social integration among African American, American Indian, and White elders. More research on the ways oral health affects the lives of older adults is warranted.

Dental care utilization among North Carolina rural older adults.

OBJECTIVES: This analysis delineates the predisposing, need, and enabling factors that are associated with regular and recent dental care in a multiethnic sample of rural older adults. METHODS: A cross-sectional, comprehensive, oral-health survey conducted with a random, multiethnic (African American, American Indian, white) sample of 635 community-dwelling adults aged 60 years and older was completed in two rural southern counties. Logistic regression models assessed the simultaneous associations of dental care with predisposing, enabling, and need factors. RESULTS: Almost no edentulous rural older adults received dental care; 27.1 percent of dentate rural older adults had received regular dental care, and 36.7 percent had received recent dental care. Predisposing (less than high-school education, dental anxiety), enabling (no regular place for dental care), and need factors (no filled teeth) reduced the odds of regular dental, while predisposing (dental anxiety), enabling (no regular place for dental care), and need factors (no filled teeth) reduced the odds of recent dental care. Having excellent, very good, or good self-rated oral health increased the odds of receiving regular and recent dental care. CONCLUSIONS: Regular and recent dental care are infrequent among rural older adults. Contrary to expectations, those not receiving dental care are those who most need care; this has been referred to as the Paradox of Dental Need. Community access to dental care and the ability of older adults to pay for dental care must be addressed by public-health policy to improve the health and quality of life of older adults in rural communities.

Dental anxiety and oral health outcomes among rural older adults.

OBJECTIVES: The objective of this study is to determine the degree to which rural older adults are able to complete a measure of dental anxiety and to assess the prevalence, as well as the demographic and oral health characteristics, of individuals reporting high dental anxiety. METHODS: A population-based sample of 635 African American, American Indian and White older adults (age ≥ 60 years) completed an in-home survey, and 362 dentate participants completed an oral examination. Dental anxiety was measured using the four-item Corah's Dental Anxiety Scale (DAS). Gender, ethnicity, age, education, and oral health outcomes were compared between those who completed all four DAS questions (completers) and those who did not (noncompleters) as well as, among completers, those with high versus low DAS scores. RESULTS: There were 94 (14.8%) noncompleters. Noncompletion was associated with older age, lower education, being edentulous, and having gingival recession. 12.4% of DAS completers had high DAS scores, which was more common among those aged 60-70 years, women, and those with oral pain and sore or bleeding gums. In logistic regression analysis, only sore and bleeding gums had a significant association with a high DAS score (odds ratio = 2.40, 95% confidence interval 1.09-5.26). CONCLUSIONS: About one in eight rural older adults have high dental anxiety, which is associated with poor oral health outcomes. Identifying new approaches to measure dental anxiety among a population with limited interaction with dental care providers is needed.

Meal patterns and food choices of young African-American men: understanding eating within the context of daily life.

Although young African-American men are at particularly high risk of developing hypertension at an early age, dietary interventions that have successfully reduced blood pressure among African-American adults have not been translated into programs for this group. Life contexts such as school enrollment, participation in competitive athletics, and employment influence the daily activities and meal patterns of African-American men. This study explored the activities of young African-American men to identify opportunities to increase healthful food choices. A purposive sample was recruited that included five groups of African-American men aged 15 to 22 years (N=106): high school athletes and nonathletes, college athletes and nonathletes, and nonstudents. A structured interview guided participants through a description of their activities, meal patterns, and food choices during the course of a typical weekday. Common elements emerged that provided a contextual view of the participant meal patterns and food choices. These elements were sports team participation, college employment, school as a food source, nonstudent status, and eating dinner at home. These findings suggest opportunities for the design of dietary interventions for young African-American men that take into consideration how school, athletics, and employment may influence opportunities to eat regular meals that include healthful foods.

Dry mouth and dietary quality in older adults in north Carolina.

OBJECTIVES: To quantify prevalence of dry mouth, association between dry mouth and beverage intake and dietary quality, and association between dry mouth and self-reported dietary accommodations to oral health deficits. DESIGN: Cross-sectional study; data from self-reports. SETTING: Rural North Carolina counties with substantial African-American and American Indian populations. PARTICIPANTS: Six hundred twenty-two participants aged 60 and older. MEASUREMENTS: Data included the 11-item Xerostomia Inventory (higher scores connote greater effect from dry mouth), a food frequency questionnaire (converted into Health Eating Index-2005 scores), and survey items on foods modified before consumption or avoided because of oral health problems. RESULTS: Dry mouth was associated with being female, lower education, and income below the poverty level. Although overall beverage consumption did not vary with dry mouth, consumption of certain sugar-sweetened beverages was positively associated with dry mouth. Overall dietary quality did not differ with dry mouth, but more-severe dry mouth was associated with lower intake of whole grains and higher intakes of fruits. Dry mouth was strongly associated with self-reported modification and avoidance of foods. Those in the highest tertile of dry mouth were more likely to modify several foods than those in the lowest tertile and were more likely to avoid three or more foods. CONCLUSION: Older adults appear to modify foods or selectively avoid foods in response to perceived dry mouth. Despite these behaviors, dry mouth does not result in poorer dietary quality.

Impact of denture usage patterns on dietary quality and food avoidance among older adults.

This study categorizes older adults living in rural areas by denture status, assesses the frequency of wearing dentures during meals, and determines whether denture status or use is associated with dietary quality or the number of foods avoided. A multi-ethnic population-based sample of adults ≥60 years (N = 635) in the rural United States was interviewed. Survey included denture use, removing dentures before eating, and foods avoided due to oral health problems. Dietary intakes were converted into Healthy Eating Index-2005 scores. Sixty percent wore removable dentures of some type; 55% never, 27% sometimes, and 18% always removed dentures when eating. More frequent removal was associated with lower dietary quality and more foods avoided. Those with severe tooth loss had the lowest dietary quality and avoided the most foods. Many rural older adults wear dentures. Learning how they adapt to denture use will offer insight into their nutritional self-management and help explain differences in dietary quality.

Association between dietary quality of rural older adults and self-reported food avoidance and food modification due to oral health problems.

OBJECTIVES: To quantify the association between food avoidance and modification due to oral health problems, to examine the association between food practices and dietary quality, and to determine foods associated with these self-management behaviors. DESIGN: Cross-sectional. SETTING: Rural North Carolina. PARTICIPANTS: Six hundred thirty-five community-dwelling adults aged 60 and older. MEASUREMENTS: Demographic and food frequency data and oral health assessments were obtained during home visits. Avoidance (0, 1-2 foods, 3-14 foods) and modification (0-3 foods, 4-5 foods) due to oral health problems were assessed for foods representing oral health challenges. Food frequency data were converted into Healthy Eating Index-2005 (HEI-2005) scores. Linear regression models tested the significance of associations between HEI-2005 measures and food avoidance and modification. RESULTS: Thirty-five percent of participants avoided three to 14 foods, and 28% modified four to five foods. After adjusting for age, sex, ethnicity, poverty, education, and tooth loss, total HEI-2005 score was lower (P<.001) for persons avoiding more foods and higher for persons modifying more foods (P<.001). Those avoiding three to 14 foods consumed more saturated fat and energy from solid fat and added sugar and less nonhydrogenated fat than those avoiding fewer than three foods. Those who modified four to five foods consumed less saturated fat and solid fat and added sugar but more total grains than those modifying fewer than four foods. CONCLUSION: Food avoidance and modification due to oral health problems are associated with significant differences in dietary quality. Approaches to minimize food avoidance and promote food modification by persons having eating difficulties due to oral health conditions are needed.

Severe tooth loss in older adults as a key indicator of compromised dietary quality.

OBJECTIVE: Poor oral health influences the dietary quality of older individuals. The objective of the present study was to relate the number of teeth to adherence to the 2005 Dietary Guidelines for Americans among an ethnically diverse sample of older adults. DESIGN: A block cluster design was used to obtain a sample of older adults. Data were weighted to census data for ethnicity and gender. Dietary intakes were assessed using an FFQ and converted into Healthy Eating Index-2005 (HEI-2005) scores. SETTING: Two counties in North Carolina, USA, with large African-American and American Indian populations. SUBJECTS: Community-dwelling older adults (N 635). RESULTS: Three hundred and twenty-six participants had severe tooth loss (0-10 teeth remaining), compared with 305 participants with 11+ teeth. After controlling for socio-economic factors, those with 0-10 teeth had lower total HEI-2005 scores and consumed less Total Fruit, Meat and Beans, and Oils, and more energy from Solid Fat, Alcohol and Added Sugar, compared with those with 11+ teeth. Less than 1 % of those with 0-10 teeth and 4 % of those with 11+ teeth met overall HEI-2005 recommendations. Those with 0-10 teeth were less likely to eat recommended amounts of Total Vegetables, Dark Green and Orange Vegetables, and energy from Solid Fat, Alcohol and Added Sugar. CONCLUSIONS: Older adults with severe tooth loss are less likely than those with moderate to low tooth loss to meet current dietary recommendations. Nutrition interventions for older adults should take oral health status into consideration and include strategies that specifically address this as a barrier to healthful eating.

Food avoidance and food modification practices of older rural adults: association with oral health status and implications for service provision.

PURPOSE: Dietary variation is important for health maintenance and disease prevention among older adults. However, oral health deficits impair ability to bite and chew foods. This study examines the association between oral health and foods avoided or modified in a multiethnic rural population of older adults. It considers implications for nutrition and medical service provision to this population. DESIGN AND METHODS: In-home interviews and oral examinations were conducted with 635 adults in rural North Carolina counties with substantial African American and American Indian populations. Avoidance and modification data were obtained for foods representing different dental challenges and dietary contributions. Data were weighted to census data for ethnicity and sex. Bivariate analyses of oral health measures and foods avoided used chi-square and logistic regression tests. Multivariable analyses used proportional odds or nominal regression models. RESULTS: Whole fruits and raw vegetables were the most commonly avoided foods; substantial proportions of older adults also avoided meats, cooked vegetables, and other foods. Food avoidance was significantly associated with self-rated oral health, periodontal disease, bleeding gums, dry mouth, having dentures, and having fewer anterior and posterior occlusal contacts. Associations persisted when controlling for demographic and socioeconomic status indicators. From 24% to 68% of participants reported modifying specific fruits, vegetables, and meats. Modifying harder foods was related to location of teeth and periodontal disease and softer foods to oral pain and dry mouth. IMPLICATIONS: Food services for older adults should consider their oral health status. Policy changes are needed to provide oral health care in benefits for older adults.

The diet quality of rural older adults in the South as measured by healthy eating index-2005 varies by ethnicity.

The 2005 Dietary Guidelines for Americans publication placed increased emphasis on the importance of consuming a wide range of healthful foods and further reducing the consumption of less healthful ones. These recommendations are challenging for rural elders whose functional limitations, fewer resources, and limited access to foods negatively affect the quality of their diets. The purpose of this study was to characterize the diet quality of a multiethnic population-based sample of older adults (N=635) in the southern United States. Data were collected via home visit; dietary intakes were assessed using a food frequency questionnaire and converted into Healthy Eating Index-2005 (HEI-2005) scores used to monitor adherence to dietary guidelines. The mean total HEI-2005 score was 61.9/100 with fewer than 2% meeting the recommended score of 80/100. After controlling for age, sex, marital status, poverty status, and education, African Americans (n=136) had higher total HEI-2005 scores compared to American Indians (n=195) and non-Hispanic whites (n=304) (64.5 vs 60.1 and 61.1 respectively, P=0.001). Certain HEI-2005 foods were consumed in greater amounts by particular groups, such as total fruit and meat and beans (African Americans), whole fruit and grains (African Americans and American Indians), milk (non-Hispanic whites), and energy from solid fat, alcohol, and added sugars (American Indians). The overall diet quality of these rural elders was not adequate as determined by the HEI-2005; however, intakes of dark green and orange vegetables were adequate, and many participants were in compliance with the added fat and sugar guidelines. Determination of factors that promote or prevent the consumption of healthful foods among rural elders may help tailor nutrition education programs for these vulnerable communities.

Disparities in oral health status between older adults in a multiethnic rural community: the rural nutrition and oral health study.

OBJECTIVES: To compare oral health status according to ethnicity and socioeconomic status in African-American, American-Indian, and white dentate and edentulous community-dwelling older adults. DESIGN: Cross-sectional study; data from self-reports and oral examinations. PARTICIPANTS: A multistage cluster sampling design was used to recruit 635 participants aged 60 and older from rural North Carolina counties with substantial African-American and American-Indian populations. MEASUREMENTS: Participants completed in-home interviews and oral examinations. Self-reported data included sociodemographic indicators; self-rated oral health status; presence or absence of periodontal disease, bleeding gums, oral pain, dry mouth; and fit of prostheses. Oral examination data included number of teeth and numbers of anterior and posterior functional occlusal units. RESULTS: African Americans and American Indians had significantly lower incomes and educational attainment than whites. Self-rated oral health was significantly better in whites than in African Americans and American Indians. Prevalence of self-reported periodontal disease and bleeding gums was lower in whites. Of dentate participants, African Americans were significantly more likely than whites to have 11 to 20 teeth and one or two posterior occlusal contacts. Oral health deficits remained associated with ethnicity when adjusted for socioeconomic variables. CONCLUSION: Oral health disparities in older adults in a multiethnic rural area were largely associated with ethnicity and not socioeconomic status. Clinicians should be aware of these health disparities in oral health status and their possible role in disparities in chronic disease. Further research is necessary to understand whether these oral health disparities reflect current or lifetime access to care, diet, or attitudes toward oral health care.

Oral health self-care behaviors of rural older adults.

OBJECTIVES: This analysis describes the dental self-care behaviors used by a multiethnic sample of older adults and delineates the associations of self-care behaviors with personal characteristics and oral health problems. METHODS: A cross-sectional comprehensive oral health survey conducted with a random, multiethnic (African-American, American Indian, white) sample of 635 community-dwelling rural adults aged 60 years and older was completed in two rural southern counties. RESULTS: Rural older adults engage in a variety of self-care behaviors, including the use of over-the-counter (OTC) medicine (12.1 percent), OTC dental products (84.0 percent), salt (50.9 percent), prayer (6.1 percent), and complementary therapies (18.2 percent). Some gender and ethnic class differences are apparent, with greater use by women of OTC medicine and salt and greater use by African-Americans and American Indians of OTC medicine and OTC dental products. The use of dental self-care behaviors appears to be driven by need. Those reporting oral pain, bleeding gums, and dry mouth have greater odds of engaging in most of the dental self-care behaviors, including the use of complementary therapies. CONCLUSIONS: The major factor leading to the use of self-care behaviors is need. Although oral pain does increase the use of self-care behaviors, so do bleeding gums and dry mouth. Research and practice should address self-care behaviors used for oral health problems in addition to pain. Investigators should expand analysis of dental self-care behavior and the relationship of self-care behavior to the use of professional services. Further research also should explore the use of complementary therapies in dental self-care.

Views of hypertension among young African Americans who vary in their risk of developing hypertension.

OBJECTIVES: To describe beliefs about hypertension and health education of young African American adults varying in their hypertension risk status. DESIGN: Fifty-eight African American young adults (17-20 years) were selected based on low and high risk criteria for hypertension assessed in earlier investigations of hemodynamic responses to stress. The sample included 15 high risk males, 13 low risk males, 14 high risk females, and 16 low risk females who were interviewed indepth about their hypertension beliefs and health education experiences. Variable-based matrices identified participants with similar responses. RESULTS: Overall, participants had a limited understanding of hypertension. For example, they linked the condition to eating a diet high in pork and fat and having a positive family history of hypertension with little acknowledgement of weight, smoking, race and sex as key contributors to hypertension onset. Distinctions were found between risk categories and along sex lines. Most high risk participants believed stress could cause hypertension. High risk females believed that they were at risk for developing hypertension but lacked prevention strategies. High risk males were generally uninformed about risk or prevention. More low risk females believed in prevention compared to few low risk males. Participants reported little formal health education about hypertension and recommended that hypertension education be improved through more effective and relevant approaches in high school health education classes. CONCLUSIONS: These findings support the need for comprehensive and revitalized hypertension prevention programs for young African Americans. Participant views varied with hypertension risk status and gender suggesting that targeted educational efforts should reflect these differences.

Use of tobacco products among rural older adults: prevalence of ever use and cumulative lifetime use.

Tobacco use is a well-documented contributor to morbidity and mortality in the US and worldwide. Information on the comprehensive use of tobacco products is lacking, particularly smokeless tobacco in its various forms. Data from 635 older (>/=60 years) African American, American Indian and White adults in rural North Carolina were analyzed to assess current and lifetime use of cigarettes, cigars, pipe, snuff and chewing tobacco. Participants were classified as being current, former or never users of each product. Lifetime use of each product was determined by asking about typical intensity of use per day and length of time the product has been used. About 70% of participants were current or former users of any tobacco product, and about one-third of participants currently used at least one product. Variations in use were observed by ethnicity and sex, particularly for cigarettes, snuff and chewing tobacco. Variations were also seen according to other demographic and health characteristics. These data add to a limited body of literature on lifetime use of smoked and smokeless tobacco products, and are useful in identifying the impact of these products on morbidity and mortality, particularly for vulnerable populations.

A 4-day sodium-controlled diet reduces variability of overnight sodium excretion in free-living normotensive adolescents.

The present analysis examined changes in the variability of overnight sodium excretion in 84 free-living adolescents (ages 15 to 19 years) on a 4-day sodium-controlled diet in which foods provided were selected by adolescents from an extensive list of menu items. The only selection criterion imposed was that foods selected for each day contain 4,000+/-200 mg sodium. Adolescents collected overnight urine samples. Repeated measures analysis of variance tested the effect of diet day on overnight sodium excretion, overnight urinary sodium concentration, and overnight urinary volume. Variance ratio test evaluated changes in overnight sodium excretion variance across days. Day 4 overnight sodium excretion was statistically lower than days 1 to 3 (1.84 vs 6.54, 5.94, and 5.52 mEq/h [1.84 vs 6.54, 5.94, and 5.52 mmol/h]). Day 4 overnight urinary sodium concentration was lower than days 1 to 3 (32.16 vs 119.64, 109.61, and 111.32 mEq/L [32.16 vs 119.64, 109.61, and 111.32 mmol/L]). The variance of overnight sodium excretion from day 1 to day 4 was reduced 10-fold from 20.1 mEq/h (20.1 mmol/h) to 1.90 mEq/h (1.90 mmol/h). Daily overnight urine volumes remained constant, averaging 451.7 mL/day. The dietary protocol successfully reduced the variability of sodium intake as estimated by overnight sodium excretion in free-living adolescents. The protocol could be expanded to include baseline values, additional days of sodium control, and varying levels of dietary sodium intake.

Association of ambulatory blood pressure and dietary caffeine in adolescents.

BACKGROUND: Although relatively little is known about the responsible factors, there is an increased prevalence of essential hypertension in youth. Our previous research using casual blood pressure (BP) suggests a role for caffeine intake. The objective of this study was to assess the association between caffeine intake and ambulatory BP patterns among adolescents and to replicate our previous findings that compared caffeine intake to BP values obtained at a single time point. METHODS: Eighty-two African-American and non-Hispanic white adolescents (15 to 19 years old) with normal systolic BP selected foods and beverages for a 4-day sodium-controlled diet. Subjects were stratified into three groups based on the amount of caffeine in these foods. Ambulatory BP measures (24-h) were recorded during 1 day of the 4-day diet. The effects of ethnicity, caffeine, and the interaction of ethnicity and caffeine on BP were assessed for daytime and nighttime hours controlling for gender and body mass index. RESULTS: The level of dietary caffeine was positively associated with daytime systolic BP (F(2,76) = 3.1, P = .05, partial R(2) = 0.07) and daytime diastolic BP (F = 3.53(2,76), P = .03, partial R(2) = 0.07). Caffeine's effect on systolic BP was most pronounced for African-American subjects. These results replicated our earlier findings. There was no association between caffeine intake and nighttime BP. CONCLUSIONS: This investigation replicates and extends our previous findings that caffeine consumption impacts the BP of adolescents, during the daytime when sympathetic nervous system responses dominate BP control. Controlled studies that examine the pressor effects of caffeine intake at levels typical of the dietary patterns of today's adolescents are needed.