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D R Jacobs

Publications and source records attributed to D R Jacobs.

At least 19 recordsLinked to original sources
PubMed2006

Recent exposure to particulate matter and C-reactive protein concentration in the multi-ethnic study of atherosclerosis.

Ambient levels of particulate matter have been linked to cardiovascular disease. The mechanisms mediating these associations are poorly understood. One candidate mechanism is inflammation. Using data from the Multi-Ethnic Study of Atherosclerosis (2000-2002), the authors investigated the relation between exposure to particulate matter of less than or equal to 2.5 microm in diameter (PM2.5) and C-reactive protein concentration in 5,634 persons aged 45-84 years who were free of cardiovascular disease. Data from US Environmental Protection Agency monitors were used to estimate PM2.5 exposures for the prior day, prior 2 days, prior week, prior 30 days, and prior 60 days. Only the 30-day and 60-day mean exposures showed a weak positive association with C-reactive protein, and confidence intervals were wide: relative increases in C-reactive protein per 10 microg/m3 of PM2.5 adjusted for person-level covariates were 3% (95% confidence interval (CI): -2, 10) for a 30-day mean and 4% (95% CI: -3, 11.0) for a 60-day mean. The means of 7-day, 30-day, and 60-day exposures were weakly, positively, and nonsignificantly associated with the odds of C-reactive protein of greater than or equal to 3 mg/liter: adjusted odds ratios were 1.05 (95% CI: 0.96, 1.15), 1.12 (95% CI: 0.98, 1.29), and 1.12 (95% CI: 0.96, 1.32), respectively. Slightly stronger associations were observed in persons without other risk factors for elevated C-reactive protein, but this heterogeneity was not statistically significant. The authors' results are not compatible with strong effects of particulate matter exposures on population levels of C-reactive protein.

Aged↗
PubMed2005

Comparison of body fatness measurements by BMI and skinfolds vs dual energy X-ray absorptiometry and their relation to cardiovascular risk factors in adolescents.

OBJECTIVE: To compare estimates of adiposity by dual emission X-ray absorptiometry (DXA), skinfolds and body mass index (BMI); and to evaluate the relation of these measures to cardiovascular risk in adolescents. DESIGN: In a cohort of adolescents participating in a longitudinal study of insulin resistance, Slaughter formulas were used to estimate adiposity from skinfolds and DXA was used to estimate adiposity as % body fat (%BF) and fat mass (FBM). BMI, blood pressure, lipids and insulin resistance were measured. SUBJECTS: Male and female, 11-17 y old (n=130). MEASUREMENTS: To compare DXA with two office-based methods of assessing fatness and cardiovascular risk. RESULTS: Slaughter estimates were highly correlated with DXA (%BF r=0.92, P=0.0001; FBM r=0.96, P=0.0001). Correlations were similar in heavy and thin children. BMI was also highly correlated with DXA (%BF r=0.85, P=0.0001; FBM r=0.95, P=0.0001), and these relations were stronger in heavy than thin children. BMI and the Slaughter formulas were similar to DXA in their relations to cardiovascular risk factors. CONCLUSIONS: Adiposity by BMI and Slaughter formulas are highly correlated with DXA and similarly related to cardiovascular risk factors. BMI is easy to obtain and is an acceptable method for initial office estimation of body fatness. BMI and skinfolds compare well with DXA in predicting adverse cardiovascular risk profile.

Absorptiometry, Photon↗
PubMed2004

Dietary iron intake and Type 2 diabetes incidence in postmenopausal women: the Iowa Women's Health Study.

AIMS/HYPOTHESIS: Recently, a clear biological link between iron metabolism and diabetes has emerged from epidemiological and experimental studies. We carried out a prospective study of dietary iron intake and incidence of Type 2 diabetes. METHODS: 35,698 postmenopausal women initially aged 55 to 69 years were followed for 11 years. Diet was assessed with a food frequency questionnaire at baseline. RESULTS: Intake of heme iron showed a positive association with incident Type 2 diabetes; the relative risks were 1.0, 1.07, 1.12, 1.14, and 1.28 across quintiles of heme iron (p trend =0.02) after adjustment for non-dietary and dietary risk factors. Heme iron showed a weak positive association among non-drinkers, but the association appeared to be stronger among subjects who consumed more alcohol. For example, in a model restricted to those who drank alcohol at least 15 g/day, adjusted relative risks across quintiles of heme iron were 1.0, 2.26, 3.22, 1.92, and 4.42 (p trend =0.05); and consumers of 30 g/day of more of supplemental iron had an adjusted relative risk equal to 3.03 (95% CI, 1.29-7.12)], compared to those who took no iron supplement. Non-heme iron was inversely associated with incidence of Type 2 diabetes. Amongst non-drinkers adjusted relative risks were 1.0, 0.83, 0.87, 0.72, and 0.67 across quintiles (p trend <0.01). This inverse association was lost among drinkers, in whom there was no association of diabetes incidence with non-heme iron. CONCLUSIONS/INTERPRETATION: Greater dietary heme-iron intake and/or supplemental iron were associated with an increased risk of Type 2 diabetes, especially amongst those who drink alcohol.

Aged↗
PubMed2004

Dietary intake of n-3, n-6 fatty acids and fish: relationship with hostility in young adults--the CARDIA study.

BACKGROUND: Hostility has been shown to predict both the development and manifestation of coronary disease. Examining the inter-relation of dietary intake of fish and of polyunsaturated (n-3 and n-6) essential fatty acids with hostility may provide additional insights into the cardioprotective effect of dietary fish and polyunsaturated fatty acids. OBJECTIVE: To examine the association of dietary n-3, n-6 fatty acids and fish with level of hostility in a sample of 3581 urban white and black young adults. DESIGN: Cross-sectional observational study as part of an ongoing cohort study. A dietary assessment in 1992-1993 and measurement of hostility and other covariates in 1990-1991 were used in the analysis. RESULTS: The multivariate odds ratios of scoring in the upper quartile of hostility (adjusting for age, sex, race, field center, educational attainment, marital status, body mass index, smoking, alcohol consumption and physical activity) associated with one standard deviation increase in docosahexaenoic acid (DHA, 22:6) intake was 0.90 (95% CI=0.82-0.98; P=0.02). Consumption of any fish rich in n-3 fatty acids, compared to no consumption, was also independently associated with lower odds of high hostility (OR=0.82; 95% CI=0.69-0.97; P=0.02). CONCLUSIONS: These results suggest that high dietary intake of DHA and consumption of fish rich in n-3 fatty acids may be related to lower likelihood of high hostility in young adulthood. The association between dietary n-3 fatty acids and hostile personality merits further research.

Adult↗
PubMed2004

Gamma-glutamyltransferase: an effect modifier in the association between age and hypertension in a 4-year follow-up study.

We performed a prospective study to assess whether the relationship of age with hypertension was stronger in men with high normal serum gamma glutamyltransferase (GGT) than in those with lower GGT levels. The study population included 8170 healthy male workers in a steel manufacturing company who had undergone health examinations in both 1994 and 1998. The higher the baseline GGT level, the effect of age on the development of hypertension was stronger. The incidence of hypertension among those aged 25-34, 35-44 and 45-50 years was 0.9, 2.2, 3.8% in those with GGT<20 U/l; 1.0, 4.1, 12.5% in those with GGT between 20 and 39 U/l; and 1.9, 6.3, 17.2% in those with GGT> or =40 U/l, respectively. All relationships persisted after adjusting for baseline values of body mass index, alcohol intake, smoking, exercise, family history of hypertension, systolic and diastolic blood pressure, and changes of body mass index during 4 years (P for interaction=0.03). Our data supported the hypothesis that the effect of age on the development of hypertension differed by baseline GGT level, although the underlying mechanism for this interaction is unclear.

Adult↗
PubMed2003

Gamma-glutamyltransferase and diabetes--a 4 year follow-up study.

AIMS/HYPOTHESIS: Gamma-glutamyltransferase (GGT) is located on the external surface of most cells and mediates the uptake of gluthathione, an important component of intracellular antioxidant defenses. An increase in GGT concentration has been regarded as a marker of alcohol consumption or liver disease. However, more subtle gradations in GGT could be informative because its expression is enhanced by oxidative stress and it could be released by several conditions inducing cellular stress. Recently, serum GGT concentrations have been associated with many cardiovascular disease risk factors or components of the insulin resistance syndrome. We did a prospective study with the hypothesis that serum GGT is a predictor of incident diabetes. METHODS: A total of 4,088 healthy men working in a steel manufacturing company were examined in 1994 and 1998. Diabetes was defined as a serum fasting glucose concentration of more than 126 mg/dl or the use of diabetes medication. RESULTS: There was a strong dose-response relation between serum GGT concentrations at baseline and the incidence of diabetes. In contrast to the 31% of men with GGT concentrations under 9 U/l, adjusted relative risks for incidence of diabetes for GGT concentrations 10-19, 20-29, 30-39, 40-49, and over 50 U/l were 8.0, 13.3, 12.6, 19.6 and 25.8, respectively. The associations of age and BMI with incident diabetes became stronger the higher the value of baseline serum GGT concentration. CONCLUSION/INTERPRETATION: This study suggests that an increase in GGT concentration within its physiological range is a sensitive and early biomarker for the development of diabetes.

Adult↗
PubMed2003

Area characteristics, individual-level socioeconomic indicators, and smoking in young adults: the coronary artery disease risk development in young adults study.

The 10-year follow-up examination in 1995-1996 to the population-based Coronary Artery Disease Risk Development in Young Adults Study was used to compare the strength with which socioeconomic indicators at the individual and area levels are related to smoking prevalence and to investigate contextual effects of area characteristics. When categories based on similar percentile cutoffs were compared, differences across area categories in the odds of smoking were smaller than differences across categories based on individual-level indicators. In Whites, there was evidence of a significant contextual effect of area characteristics on smoking: Living in the most disadvantaged area quartiles was associated with 50-110% higher odds of smoking, even after controlling for individual-level socioeconomic indicators. Clear contextual effects of area characteristics were not present in Blacks, but there was evidence that contextual effects may emerge at higher levels of individual-level socioeconomic position. Similar results were obtained for census tracts and block groups. Even in the presence of contextual effects, area measures may underestimate associations of individual-level variables with health outcomes. On the other hand, as illustrated by the presence of contextual effects, area- and individual-level measures are likely to tap into different constructs.

Adult↗
PubMed2002

Association of physical activity with insulin sensitivity in children.

BACKGROUND: Physical activity (PA) has been shown to improve insulin resistance and other cardiovascular disease risk factors in normal and diabetic adults and in obese youth, but not in non-diabetic, normal-weight children. METHODS: Data from 357 non-diabetic children (10-16 y) were used to examine cross-sectional associations with PA. Insulin sensitivity was assessed with a euglycemic hyperinsulinemic clamp and expressed as M(ffm) (glucose utilization/kg of fat-free mass/min). RESULTS: Correlations were adjusted for age, sex, race and Tanner stage. PA was significantly correlated with fasting insulin and insulin sensitivity (r=-0.12, P=0.03 and r=0.13, P=0.001, respectively), more strongly in children with above-median systolic blood pressure (r=-0.17, P=0.03 and r=0.35, P=0.0001, respectively). Further adjustment for body mass index, body fat percentage, waist circumference or lipids did not alter these observations. CONCLUSIONS: Physical activity is correlated with lower fasting insulin and greater insulin sensitivity in childhood. These results are consistent with the hypothesis that increasing physical activity among youth may reduce the incidence of type 2 diabetes in children and adolescents.

Adipose Tissue↗
PubMed2001

Asthma is associated with weight gain in females but not males, independent of physical activity.

We tested whether asthma diagnosis is associated with weight gain and physical activity in 4,547 18 to 30-yr-old African American and white men and women, followed prospectively for up to 10 yr. Baseline asthma was most frequent in African American men. Incident asthma was more frequent in women. Incident asthma was associated with highest and lowest baseline and change in body mass index (BMI), in a J-shaped curve, after adjustment for other factors. When stratified by sex, this association was seen only in females. Subjects on average decreased physical activity and gained weight over time, but there was no significant difference in asthma prevalence by physical activity at baseline or asthma incidence by change in physical activity. Cigarette smoking in females was significantly associated with asthma incidence, but serum cotinine level at baseline among nonsmokers (reflecting environmental tobacco smoke [ETS] exposure) was not significantly associated with asthma. We conclude that gain in BMI predisposes to new asthma diagnosis in female young adults, but decreased physical activity does not explain the association of weight gain with asthma.

Adolescent↗
PubMed2001

Trends in acute coronary heart disease mortality, morbidity, and medical care from 1985 through 1997: the Minnesota heart survey.

BACKGROUND: Coronary heart disease (CHD) mortality continued to decline from 1985 to 1997. METHODS AND RESULTS: We tabulated CHD deaths (ICD-9 codes 410 through 414) in the Minneapolis/St Paul, Minnesota, area. For 1985, 1990, and 1995, trained nurses abstracted the hospital records of patients 30 to 74 years old with a discharge diagnosis of acute CHD (ICD-9 codes 410 or 411). Acute myocardial infarction (AMI) events were validated and followed for 3-year all-cause mortality. Between 1985 and 1997, age-adjusted CHD mortality rates in Minneapolis/St Paul fell 47% and 51% in men and women, respectively; the comparable declines in US whites were 34% and 29%. In-hospital mortality declined faster than out-of-hospital mortality. The rate of AMI (ICD-9 code 410) hospital discharges declined almost 20% between 1985 and 1995, whereas the discharge rate for unstable angina (ICD-9 code 411) increased substantially. The incidence of hospitalized definite AMI declined approximately 10%, whereas recurrence rates fell 20% to 30%. Three-year case fatality rates after hospitalized AMI decreased consistently by 31% and 41% in men and women, respectively. In-hospital administration of thrombolytic therapy, emergency angioplasty, ACE inhibitors, beta-blockers, heparin, and aspirin increased greatly. CONCLUSIONS: Declining out-of-hospital death rates, declining incidence and recurrence of AMI in the population, and marked improvements in the survival of AMI patients all contributed to the 1985 to 1997 decline of CHD mortality in the Minneapolis/St Paul metropolitan area. The effects of early and late medical care seem to have had the greatest contribution to rates during this time period.

Acute Disease↗
PubMed2001

Pregnancy-related changes in body fat.

OBJECTIVE: To determine patterns of subcutaneous body fat change from preconception through 6 weeks postpartum, and factors that modify them. STUDY DESIGN: A prospective study of 557 healthy women enrolled prior to pregnancy. MAIN OUTCOME MEASURE: Body weight and skinfold thickness at the thigh, triceps, and subscapula, preconception, in each trimester, and 6 weeks postpartum, along with other variables. RESULTS: Subcutaneous body fat stores remained stable (P>0.13) during the first 6 weeks after conception, and increased from 6 to 35 weeks by 1.5 mm at the triceps, 4.2 mm at the subscapular, and 7.3 mm (P<0.01) at the thigh areas. Body fat changes correlated poorly with weight changes, reflecting differences in the time course for the changes. They differed by preconceptional body mass index (BMI), parity, and infant gender (P<0.05). Women with the highest BMIs tended to gain less subcutaneous fat early, primiparous women gained more at thigh (P=0.01) and subscapular (P=0.027), and women carrying males had higher gains at the thigh (P=0.032) and subscapular sites (P=0.058) than other women. Breastfeeding status did not affect postpartum body fat changes, but women who breastfed exclusively had significantly lower skinfold thicknesses than non-exclusive breastfeeders from preconception through 6 weeks postpartum (P=0.041). CONCLUSION: Subcutaneous body fat is stored and utilized at different sites at specific times during and after pregnancy. The pattern and amount of change varies depending on characteristics of women and their pregnancies.

Adipose Tissue↗
PubMed2001

Heart rate and mortality in a Japanese general population: an 18-year follow-up study.

The predictive power of elevated heart rate for total mortality was evaluated in a Japanese general population. A total of 573 male participants, aged 40 to 64, who underwent a health examination in 1977, were followed until 1994. Heart rate (beats per minute; bpm) was measured using an electrocardiogram. During the 18 years, 82 subjects died; 18 from cerebro-cardiovascular diseases and 36 from cancer. In a multivariate proportional hazards regression model, age, elevated systolic and diastolic blood pressures, antihypertensive medication, heart rate, uric acid, vital capacity (inversely), and serum cholesterol (inversely) were significantly associated with all-cause death. Of these variables, elevated heart rate was the strongest predictor of all-cause death after adjustment for age. Resting heart rate levels were classified into five groups: < 60 (G1), 60-69 (G2), 70-79 (G3), 80-89 (G4), and > or = 90 (G5) bpm. Heart rates of 60-69 (G2) bpm showed the lowest death rate (14.3%) and heart rate > or = 90 (G5) bpm showed the highest death rate (38.2%) after adjustments for age and other confounding factors. The relative risk of G2 versus G5 was 2.68. An increased mortality risk was shown in men whose heart rate was > or = 90 bpm. Moreover, a continuous model suggested a graded increase in risk, so that risk is likely elevated even for heart rates less than 90 bpm, and lowest risk may be around 60 bpm.

Adult↗
PubMed2001

Independent and interactive effects of apolipoprotein E phenotype and cardiorespiratory fitness on plasma lipids.

PURPOSE: To examine whether the association Apolipoprotein E (Apo E) phenotype with plasma lipids is influenced by physical fitness level. Also, to explore the interactive and independent relative contributions of Apo E phenotype, fitness (or physical activity), and other modifiable factors to variation in plasma low density lipoprotein (LDL-C) and high density lipoprotein (HDL-C) levels at baseline and over a seven-year follow-up. METHODS: Physical fitness (duration of a graded treadmill test), Apo E phenotype, plasma LDL-C and HDL-C, and covariates were measured at baseline and seven years later in a bi-racial cohort of young adults, aged 18-30 years at baseline in 1985-86, from the Coronary Artery Risk Development In Young Adults (CARDIA) study. RESULTS: Fitness did not influence the associations of Apo E and LDL-C or HDL-C. The independent effects of several modifiable variables (changes in Keys' score, smoking, oral contraceptive use, education, body weight, alcohol intake, and fitness), when combined, contributed considerably more than Apo E to the variance in LDL-C changes (6.74% or 8.71% for combined modifiable variables vs. 1.27% or 0.90% for ApoE, in women or men, respectively) and HDL-C changes (13.11% or 12.66% for combined modifiable variables vs. 0.12% or 0.02% for ApoE, in women or men, respectively). The pattern of findings was similar when self-reported physical activity was substituted for fitness. CONCLUSIONS: Changes in modifiable factors, including fitness, may be stronger correlates of changes in LDL-C and HDL-C over time than the immutable factor, Apo E phenotype.

Adolescent↗
PubMed2001

Validation of the Stanford 7-day recall to assess habitual physical activity.

PURPOSE: The ability of the Stanford 7-Day Recall (7-DR), a well known instrument for surveying work and leisure-time physical activity (PA) in epidemiologic studies, to assess levels of habitual PA in men and women was evaluated. METHODS: The 7-DR was administered twice, one month apart. Its accuracy was studied in 77 men and women, aged 20-59 years, by its repeatability and comparison of both administrations of the 7-DR with: fourteen 48-hour physical activity records; fourteen 48-hour Caltrac accelerometer readings; peak oxygen uptake (VO(2) peak) determinations; and percent body fat. These criteria measures were obtained over a year's duration. RESULTS: One month repeatability correlation coefficients for 7-DR total activity were r = 0.60 and r = 0.36 for men and women, respectively. Comparison of corresponding indices of activity between the 7-DR and the PA record indicated: 1) a closer relationship in men for total (r = 0.58 for visit 10 7-DR and 0.66 for visit 11 7-DR, p < or = 0.01), and very hard (r = 0.44 and 0.60, p< or = 0.05) activity then in women (r = 0.32 and 0.33, p < or = 0.05, and r = 0.21, ns and 0.43, p< or = 0.01, respectively); and 2) in general, lower and less consistent associations for hard, moderate, and light activity. Total PA by the 7-DR was significantly associated with Caltrac readings in men only. 7-DR results were more consistently related to VO(2) peak in men than women, but were significantly related to percent body fat in women only. CONCLUSIONS: The ability of the 7-DR to assess habitual PA was greater for more vigorous than for lower intensity PA.

Adult↗