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David R Jacobs

Publications and source records attributed to David R Jacobs.

At least 127 records · Page 7Linked to original sources
PubMed2003

Positional change in blood pressure and 8-year risk of hypertension: the CARDIA Study.

OBJECTIVE: To assess the relationship between positional blood pressure change and 8-year incidence of hypertension in a biracial cohort of young adults. SUBJECTS AND METHODS: Participants from the Coronary Artery Risk Development in Young Adults (CARDIA) study with complete data from year 2 (1987-1988), year 5 (1990-1991), year 7 (1992-1993), and year 10 (1995-1996) examinations were included (N = 2781). Participants were classified into 3 groups based on their year 2 systolic blood pressure response to standing: drop, a decrease in systolic blood pressure of more than 5 mm Hg; same, a change of between -5 and +5 mm Hg; and rise, more than 5-mm Hg increase. RESULTS: The number of participants in each group was as follows: drop, 741; same, 1590; and rise, 450. The 8-year incidence of hypertension was 8.4% in the drop group, 6.8% in the same group, and 12.4% in the rise group (P < .001). Adjusted odds ratios for developing hypertension during the follow-up period in the rise group vs the same group were as follows: in black men, 2.85 (95% confidence interval [CI], 1.43-5.69), in black women, 2.47 (95% CI, 1.19-5.11), in white men, 2.17 (95% CI, 1.00-4.73), and in white women, 4.74 (95% CI, 1.11-20.30). CONCLUSIONS: A greater than 5-mm Hg increase in blood pressure on standing identified a group of young adults at increased risk of developing hypertension within 8 years. These findings support a physiologic link between sympathetic nervous system reactivity and risk of hypertension in young adults.

Adolescent↗
PubMed2003

An after-school obesity prevention program for African-American girls: the Minnesota GEMS pilot study.

OBJECTIVE: This paper describes the development of an after-school obesity-prevention program for African-American girls, and presents findings from a 12-week pilot trial conducted by the University of Minnesota. This study was part of the GEMS project, created to test interventions designed to reduce excess weight gain in African-American girls. DESIGN: Two-arm parallel group, randomized controlled trial. Measures were taken at baseline and at 12 weeks follow up. SETTING: An after-school community program. PARTICIPANTS: Fifty-four African-American girls, 8- to 10-years of age, and their parents/caregivers. INTERVENTION: The after-school intervention was conducted twice a week for 12 weeks, and focused on increasing physical activity and healthy eating. A family component was also included. Girls in the control group received a program over 12 weeks unrelated to nutrition and physical activity. OUTCOMES: Measures included height and weight (body mass index), percent body fat (DEXA), physical activity, assessed using a CSA accelerometer and self-report, two 24-hour dietary recalls, and psycho-social and demographic variables. Parental data included demographic and psycho-social characteristics, and dietary measures. Additionally, process evaluation data on the intervention were collected. RESULTS: Recruitment goals were met. After adjustment for baseline level, follow-up BMI did not differ between the treatment groups, an expected finding, given that this was a pilot study. At 12 weeks follow up, differences between the intervention and control groups were in the hypothesized direction of change for most variables, among both the girls and their parents. Process evaluation results demonstrated that the program was well attended, and well received, by girls and parents. CONCLUSIONS: An after-school obesity prevention program for low-income African-American girls is a promising model for future efforts.

Adult↗
PubMed2002

Fifteen-year trends in cardiovascular risk factors (1980-1982 through 1995-1997): the Minnesota Heart Survey.

The objective was to describe trends in cardiovascular risk factors between 1980-1982 and 1995-1997 in metropolitan Minneapolis-St. Paul, Minnesota. Four population-based surveys of 4,000-6,000 adults aged 25-74 years were conducted in 1980-1982, 1985-1987, 1990-1992, and 1995-1997 using consistent sampling strategies and protocols. The authors completed interviews and examinations to characterize cardiovascular risk factors. Blood samples were drawn and assayed for several analytes including total cholesterol. Although total cholesterol decreased 7-9 mg/dl during the 1980s, no further reduction was noted between 1990-1992 and 1995-1997. Hypercholesterolemia prevalence (total cholesterol of >240 mg/dl and/or use of lipid-lowering medication) fell between 1980-1982 and 1990-1992 but increased thereafter. Current cigarette smoking, systolic blood pressure, and hypertension prevalence decreased significantly between 1980-1982 and 1995-1997. Body mass index increased substantially across the four surveys. Although there was little change in the mean leisure-time physical activity, the proportion of the population not engaging in regular exercise increased between 1990-1992 and 1995-1997. Dietary fat decreased consistently from 1980-1982 to 1995-1997, while overall caloric intake rose 8% in women but not men. To conclude, the favorable trends in hypertension, cigarette smoking, and dietary fat consumption observed in Minneapolis-St. Paul from 1980-1982 to 1995-1997 were paralleled by less favorable recent trends in total cholesterol, hypercholesterolemia, adiposity, and physical activity.

Adult↗
PubMed2002

Early life factors contribute to the decrease in lung function between ages 18 and 40: the Coronary Artery Risk Development in Young Adults study.

Early life factors may influence pulmonary function. We measured forced expiratory volume in 1 second (FEV(1)) in 1985-1986 and 2, 5, and 10 years later in approximately 4,000 black and white men and women initially aged 18-30 years. We estimated the age pattern of FEV(1) according to family smoking status, early diagnosis of asthma, early smoking initiation, adult asthma, and cigarette smoking. FEV(1) followed a quadratic pattern from age of peak through age 40. The pattern varied by race and sex. Early smoking initiation was associated with a faster decrease in FEV(1). Smoking by family members was related to early life asthma and may have contributed to faster FEV(1) decrease by encouraging behaviors such as heavier smoking or earlier smoking initiation. Prevalence of smoking was 28% when no family member smoked, compared with 59% when four or more members smoked. The FEV(1) decline was 8.5% in never-smokers without asthma; 10.1% in nonsmoking individuals diagnosed with asthma; and 11.1% in baseline smokers who smoked 15 or more cigarettes per day. The combination of asthma and heavier smoking was synergistic (17.8% decline). This study delineates an increased rate of decline in those with asthma or in those who smoke cigarettes and implicates early life exposures as contributing to the faster rate of FEV(1) decline.

Adolescent↗
PubMed2002

Gender- and race-specific determination of albumin excretion rate using albumin-to-creatinine ratio in single, untimed urine specimens: the Coronary Artery Risk Development in Young Adults Study.

Although albumin excretion rate is commonly estimated by using albumin/creatinine ratio (A/C), gender and race differences in creatinine excretion may bias this estimate. The authors optimize the use of an untimed (spot) urine specimen among 3,371 Blacks and Whites aged 28-40 years in the Coronary Artery Risk Development in Young Adults Study in 1995-1996. Using three 24-hour collections during the year 5 examination, they determined k = 0.68 x 0.88 in Black men, 0.88 in Black women, 0.68 in White men, and 1.0 in White women to reflect gender and race differences in creatinine excretion. The authors then computed A/C adjusted for race and sex differences in creatinine excretion (A/kC) by using an untimed urine sample in the year 10 examination. A/kC >or= 25 mg/g (194 cases of microalbuminuria and 26 cases of clinical grade albuminuria) was more common among Blacks (9.1%) than among Whites (4.2%) and among men (8.2%) than among women (5.0%). Use of the unadjusted A/C underestimated the prevalence of microalbuminuria among men by 52% and among Blacks by 26%. Adjustment of A/C permitted more accurate estimation of albumin excretion rate. Men and Blacks have a higher albumin excretion rate than do women and Whites and may thereby have an increased risk of microvascular and macrovascular disease.

Adult↗
PubMed2002

Dietary risk factors for upper aerodigestive tract cancers.

We examined the association between whole-grain intake and incident upper aerodigestive tract cancer in a cohort of 34,651 postmenopausal, initially cancer-free women. We also studied established risk factors for upper aerodigestive cancers, including fruit and vegetable intake, smoking and alcohol intake. A mailed questionnaire at baseline in 1986 included a food-frequency questionnaire and assessment of other cancer risk factors. During the 14-year follow-up period, 169 women developed cancer of the upper aerodigestive tract. For all upper aerodigestive cancers together, significant inverse associations were observed for the highest compared to the lowest tertile of whole grains [relative risk (RR) = 0.53, 95% confidence interval (CI) 0.34-0.81] and yellow/orange vegetables (RR = 0.58, 95% CI 0.39-0.87). In addition, those in the highest compared to lowest tertile of fiber intake from whole grain were less likely to develop upper aerodigestive tract cancer (RR = 0.56, 95% CI 0.37-0.84); fiber intake from refined grain was not significantly associated with upper aerodigestive tract cancer. Findings were generally similar for oropharyngeal (n = 53), laryngeal (n = 21), nasopharyngeal/salivary (n = 18), esophageal (n = 21) and gastric (n = 56) cancers, though numbers of cases were too small for statistical testing within individual cancers. These findings confirm previous observations that high intake of fruits and vegetables and that intake of whole grains and the fiber derived from them may reduce risk of upper aerodigestive tract cancers.

Aged↗
PubMed2002

Dairy consumption, obesity, and the insulin resistance syndrome in young adults: the CARDIA Study.

CONTEXT: Components of the insulin resistance syndrome (IRS), including obesity, glucose intolerance, hypertension, and dyslipidemia, are major risk factors for type 2 diabetes and heart disease. Although diet has been postulated to influence IRS, the independent effects of dairy consumption on development of this syndrome have not been investigated. OBJECTIVE: To examine associations between dairy intake and incidence of IRS, adjusting for confounding lifestyle and dietary factors. DESIGN: The Coronary Artery Risk Development in Young Adults (CARDIA) study, a population-based prospective study. SETTING AND PARTICIPANTS: General community sample from 4 US metropolitan areas of 3157 black and white adults aged 18 to 30 years who were followed up from 1985-1986 to 1995-1996. MAIN OUTCOME MEASURE: Ten-year cumulative incidence of IRS and its association with dairy consumption, measured by diet history interview. RESULTS: Dairy consumption was inversely associated with the incidence of all IRS components among individuals who were overweight (body mass index > or =25 kg/m(2)) at baseline but not among leaner individuals (body mass index < 25 kg/m(2)). The adjusted odds of developing IRS (2 or more components) were 72% lower (odds ratio, 0.28; 95% confidence interval, 0.14-0.58) among overweight individuals in the highest (> or =35 times per week, 24/102 individuals) compared with the lowest (<10 times per week, 85/190 individuals) category of dairy consumption. Each daily occasion of dairy consumption was associated with a 21% lower odds of IRS (odds ratio, 0.79; 95% confidence interval, 0.70-0.88). These associations were similar for blacks and whites and for men and women. Other dietary factors, including macronutrients and micronutrients, did not explain the association between dairy intake and IRS. CONCLUSIONS: Dietary patterns characterized by increased dairy consumption have a strong inverse association with IRS among overweight adults and may reduce risk of type 2 diabetes and cardiovascular disease.

Adult↗
PubMed2002

Trends in the incidence of coronary heart disease and stroke and the prevalence of cardiovascular risk factors among Japanese men from 1963 to 1994.

PURPOSE: To determine trends in the incidence of cardiovascular disease in Japan, we examined observational data on coronary heart disease, stroke, and cardiovascular risk factors among urban Japanese working men. SUBJECTS AND METHODS: The surveyed population included all male employees aged 40 to 59 years who worked for eight industrial companies in Osaka, the second largest metropolitan city in Japan. Surveillance for cardiovascular disease and risk factors was conducted from 1963 to 1994. RESULTS: The age-adjusted incidence of coronary heart disease increased from 0.4 per 1000 person-years during 1963 to 1970, to 1.5 per 1000 person-years during 1979 to 1986, and then plateaued until 1987 to 1994 (P for trend = 0.002), whereas the incidence of stroke declined from 1.2 per 1,000 person-years during 1971 to 1978, to 0.6 per 1,000 person-years in 1987 to 1994 (P for trend = 0.02). The age-adjusted mean (+/- SD) total cholesterol level, which was 4.87 +/- 2.88 mmol/L during 1963 to 1966, increased to 5.11 +/- 0.62 mmol/L during 1982 to 1983 (P <0.001), and 5.09 +/- 0.75 mmol/L during 1990 to 1991. Both mean systolic and diastolic blood pressures increased by 1 mm Hg between the periods of 1966 to 1967 and 1982 to 1983, and declined below the 1966 to 1967 levels during 1990 to 1991. The prevalence of smoking declined from 72% during 1975 to 1976, to 58% during 1990 to 1991 (P for trend <0.001). CONCLUSION: Although these findings were limited to urban middle-aged men, the increase in serum cholesterol is likely to attenuate the reduction in future rates of coronary heart disease in Japan that would have been expected to result from the declining prevalence of smoking.

Adult↗
PubMed2002

Gamma-glutamyltransferase, alcohol, and blood pressure. A four year follow-up study.

PURPOSE: We performed this study to see: 1) whether gamma-glutamyltransferase (GGT) was a predictor for hypertension irrespective of amount of alcohol consumption; and 2) whether the relationship between alcohol consumption and blood pressure (BP) was different depending on GGT. METHODS: This study included 8170 healthy male workers in a steel manufacturing company who had undergone health examinations in both 1994 and 1998. RESULTS: The adjusted relative risk (RR) for hypertension over four years among those with GGT >or=30 U/L at baseline was 1.6 (95% confidence interval (CI): 1.1-2.4), compared to those with GGT < 30 U/L. This relationship was shown only in drinkers. Among subjects with GGT < 30U/L, no matter how much the subjects drank, the risk of hypertension in drinkers was similar with that of non-drinkers. However, among those with GGT >or=30 U/L, adjusted RRs for light, moderate, and heavy drinkers compared to non-drinkers were 1.4 (95% CI: 0.5-4.5), 5.2 (95% CI: 1.5-18.0), and 5.3 (95% CI: 1.0-27.6). CONCLUSIONS: This study showed that elevated GGT could be a predictor for hypertension in drinkers and the relationship between alcohol consumption and hypertension was shown only among those with GGT >or= 30 U/L at baseline. These findings suggest that increased serum GGT levels may reflect individual susceptibility to the blood pressure raising effect of alcohol.

Adult↗
PubMed2002

Dietary catechins and cancer incidence among postmenopausal women: the Iowa Women's Health Study (United States).

OBJECTIVE: Catechins are bioactive flavonoids present in tea, fruits, and vegetables. Previous epidemiological studies regarding tea and cancer risk were inconclusive, possibly because catechins are also present in other plant foods. We investigated whether a high intake of catechins are associated with cancer incidence among postmenopausal women. METHODS: A cohort of 34,651 postmenopausal cancer-free women aged 55-69 years were followed from 1986 to 1998. At baseline, data on diet, medical history, and lifestyle were collected. Incident cancers were obtained through linkage with a cancer registry. Cox proportional hazards analysis was used to estimate risk ratios. RESULTS: After adjustment for potential confounders, catechin intake was inversely associated with rectal cancer incidence only (risk ratios from lowest to highest quartile: 1.00, 0.93, 0.73, and 0.55; p for trend 0.02). Non-significant inverse trends were found for cancer of the upper digestive tract, pancreas, and for hematopoietic cancers. Catechins derived primarily from fruits, (+)-catechin and (-)-epicatechin, tended to be inversely associated with upper digestive tract cancer, whereas catechins derived from tea were inversely associated with rectal cancer. CONCLUSIONS: Among several cancers studied, our data suggest that catechin intake may protect against rectal cancer. The distinct effects found for catechins derived from solid foods (fruits) and beverages (tea) may be due to differences in bioavailability or metabolism of the catechins, or to their interactions with other dietary components.

Aged↗
PubMed2002

Declining beta-cell function in type 2 diabetes: 5-year follow-up and immunologic studies of the population of Wadena, MN.

The aim of the study was to describe 5-year changes in meal-stimulated pancreatic insulin reserve in adults with normal and impaired glucose tolerance (NGT, IGT) and diabetes, with or without islet-related antibodies. This was a 5-year follow-up of 270 residents of Wadena, MN, of northern European origin, with good kidney function, defined as creatinine clearance greater than 60 mL/min/1.73 m(2). The subjects comprised a population-based sample originally studied in 1986 to 1987. Urine C-peptide (CP), in a 260-minute collection, was the integrated measure of insulin secretion; Ensure-Plus (Ross, Columbus, OH) was the liquid meal. Islet cytoplasmic antibodies (ICA), insulin autoantibodies (IAA), and glutamate decarboxylase antibodies (GAD65ab) were measured. In 182 subjects with NGT, there was no mean within-subject change in urine CP over 5 years (P =.34). In 41 subjects with impaired GT (IGT), there was a moderate, but nonsignificant, increase in mean CP, and 6 (15%) subjects increased. In 37 type 2 diabetic subjects not taking insulin (type 2-No Ins), who had a mean diabetes duration at the 5-year examination of 9.6 +/- 6.3 years, there was a 21% decrease in mean urine CP (P =.012), attributable mostly to a major drop in 8 of the 37 subjects (22%). Islet-related antibody tests were mostly negative; GAD65ab positivity was related to CP decline only among insulin-taking subjects. In summary, in Wadena adults, meal-stimulated urine CP was stable or increased over 5 years in subjects with NGT and IGT, but CP decreased significantly in about one fifth of type 2-No Ins subjects, with no relation to antibody test results.

Adult↗
PubMed2002

Whole grain food intake elevates serum enterolactone.

Both intake of whole grain and higher levels of serum enterolactone have been related to reduced risk for CHD and some cancers. Because lignans are prevalent in the outer layers of grains, these findings may be related. We carried out a crossover feeding study in which overweight, hyperinsulinaemic, non-diabetic men (n 5) and women (n 6) ate, in random order, wholegrain foods or refined-grain foods in a diet with 30 % energy from fat. The dominant whole grain was wheat, followed by oats and rice. All food was supplied by the investigators and each diet lasted for 6 weeks, with an intervening washout period of 6-9 weeks. Serum enterolactone concentrations were higher when eating the wholegrain than the refined-grain diet by 6.2 (within person SE 1.7) nmol/l (P=0.0008). Most of the increase in serum enterolactone when eating the wholegrain diet occurred within 2 weeks, though the serum enterolactone difference between wholegrain and refined-grain diets continued to increase through 6 weeks. Serum enterolactone concentrations can be raised by eating a diet rich in whole grains.

4-Butyrolactone↗
PubMed2002

Exploring predictors of eating behaviour among adolescents by gender and socio-economic status.

OBJECTIVE: Guided by theory, this study explored cross-sectional differences in factors influencing adolescent eating behaviour including gender and socio-economic status (SES), and subsequently tested the longitudinal predictive power of the models. DESIGN/SETTING/SUBJECTS: Data were collected by questionnaires in a longitudinal study of adolescents (age 13 years at baseline) and their parents from Hordaland County, Norway. Association of personal and environmental variables (family, friends, school/society) with the consumption of fruit and vegetables (FV) and selected sources of fat and of sugar were assessed at age 15 The final cross-sectional models were subsequently employed in groups stratified by gender/SES and to predict consumption at age 21 RESULTS: The model explained more of the variation in the sugar score (21%) and the FV score (13.5%) than in the fat score (5%). SES was associated with both the sugar and FV scores. The strongest associations with the sugar score and FV were for antisocial behaviour and evaluation of own diet, respectively. The former association was significant in all gender/SES groups, whereas the latter association was only significant in the low SES groups. For all three types of food, the strongest significant predictors in the longitudinal models were frequency of consumption at age 15. CONCLUSION: The model's ability to explain variation in eating behaviours differed by food type, and possibly by gender/SES, but previous eating behaviour was an important predictor for all three foods. Prospective studies should carefully operationalize theoretical constructs when further investigating the influences of and interrelationships between these factors and gender/SES on the development of eating behaviours.

Adolescent↗
PubMed2002

Comparison of energy expenditure estimates from doubly labeled water, a physical activity questionnaire, and physical activity records.

BACKGROUND: Various methods are used by epidemiologists to estimate the energy cost of physical activity; these include physical activity records and recalls. However, there is limited validation of these methods against the doubly labeled water technique for determining energy expenditure (EE). OBJECTIVE: We compared EE as estimated by indirect methods (physical activity records and recall questionnaires) used in epidemiologic studies with EE obtained from doubly labeled water (EE(DLW)) in free-living men. DESIGN: We determined EE(DLW), energy intake at weight maintenance, and EE from 7-d physical activity records (EE(Record)) and a 7-d physical activity recall questionnaire (EE(Recall)) in 24 men aged 41 plus minus 2.0 y ( plus minus SEM) with a body mass index (in kg/m(2)) of 25.1 plus minus 0.5. RESULTS: There was excellent agreement between EE(DLW) (13.27 plus minus 0.35 MJ/d) and energy intake (13.19 plus minus 0.36 MJ/d), with a difference of 0.5 plus minus 1.0% ( plus minus SE). The indirect measures of physical activity and EE were 14.17 plus minus 0.37 MJ/d for EE(Record) (difference from EE(DLW): 7.9 plus minus 3.2%) and 17.40 plus minus 1.45 MJ/d for EE(Recall) (difference from EE(DLW): 30.6 plus minus 9.9%). CONCLUSIONS: Seven-day physical activity records provide an acceptable estimate of EE in free-living adults compared with EE(DLW), but 7-d physical activity recalls have limited application to estimate daily EE. For optimal validity, the 7-d physical activity records require good subject compliance and the provision of careful instructions for their use.

Adult↗
PubMed2002

Effect of whole grains on insulin sensitivity in overweight hyperinsulinemic adults.

BACKGROUND: Epidemiologic studies have found whole-grain intake to be inversely associated with the risk of type 2 diabetes and heart disease. OBJECTIVE: We tested the hypothesis that whole-grain consumption improves insulin sensitivity in overweight and obese adults. DESIGN: This controlled experiment compared insulin sensitivity between diets (55% carbohydrate, 30% fat) including 6-10 servings/d of breakfast cereal, bread, rice, pasta, muffins, cookies, and snacks of either whole or refined grains. Total energy needs were estimated to maintain body weight. Eleven overweight or obese [body mass index (in kg/m(2)): 27-36] hyperinsulinemic adults aged 25-56 y participated in a randomized crossover design. At the end of each 6-wk diet period, the subjects consumed 355 mL (12 oz) of a liquid mixed meal, and blood samples were taken over 2 h. The next day a euglycemic hyperinsulinemic clamp test was administered. RESULTS: Fasting insulin was 10% lower during consumption of the whole-grain than during consumption of the refined-grain diet (mean difference: -15 +/- 5.5 pmol/L; P = 0.03). After the whole-grain diet, the area under the 2-h insulin curve tended to be lower (-8832 pmol.min/L; 95% CI: -18720, 1062) than after the refined-grain diet. The rate of glucose infusion during the final 30 min of the clamp test was higher after the whole-grain diet (0.07 x 10(-4) mmol.kg(-1).min(-1) per pmol/L; 95% CI: 0.003 x 10(-4), 0.144 x 10(-4)). CONCLUSION: Insulin sensitivity may be an important mechanism whereby whole-grain foods reduce the risk of type 2 diabetes and heart disease.

Adult↗