Angiotensin II type 1 receptor polymorphisms and susceptibility to hypertension: A HuGE review

The angiotensin II type 1 receptor (AGTR1) plays an integral role in blood pressure control, and is implicated in the pathogenesis of hypertension. Polymorphisms within this gene have been extensively studied in association with hypertension; however, findings are conflicting. To clarify these data, we conducted a systematic review of association studies of AGTR1 polymorphisms and hypertension, and performed a meta-analysis of the rs5186 variant. Results show that the currently available literature is too heterogeneous to draw meaningful conclusions. The definition of hypertension and gender composition of individual studies helps to explain this heterogeneity. Although the structure and splicing pattern of AGTR1 would suggest a likely effect of polymorphisms within the promoter region on gene function, few studies have been conducted thus far. In conclusion, there is insufficient evidence that polymorphisms in the AGTR1 gene are risk factors for hypertension. However, most studies are inadequately powered, and larger well-designed studies of haplotypes are warranted

Physical activity and pre-diabetes—an unacknowledged mid-life crisis: findings from NHANES 2003–2006

The prevalence of pre-diabetes (PD) among US adults has increased substantially over the past two decades. By current estimates, over 34% of US adults fall in the PD category, 84% of whom meet the American Diabetes Association’s criteria for impaired fasting glucose (IFG). Low physical activity (PA) and/or sedentary behavior are key drivers of hyperglycemia. We examined the relationship between PD and objectively measured PA in NHANES 2003–2006 of 20,470 individuals, including 7,501 individuals between 20 and 65 yrs.We excluded all participants without IFG measures or adequate accelerometry data (final N = 1,317). Participants were identified as PD if FPG was 100–125 mg/dL (5.6–6.9 mmol/L). Moderate and vigorous PA in minutes/day individuals were summed to create the exposure variable “moderate-vigorous PA” (MVPA). The analysis sample included 884 normoglycemic persons and 433 with PD. There were significantly fewer PD subjects in the middle (30.3%) and highest (24.6%) tertiles of PA compared to the lowest tertile (35.5%). After adjusting for BMI, participants were 0.77 times as likely to be PD if they were in the highest tertile compared to the lowest PA tertile (p < 0.001). However, these results were no longer significant when age and BMI were held constant. Univariate analysis revealed that physical activity was associated with decreased fasting glucose of 0.5 mg/dL per minute of MVPA, but multivariate analysis adjusting for age and BMI was not significant. Overall, our data suggest a negative association between measures of PA and the prevalence of PD in middle-aged US adults independent of adiposity, but with significant confounding influence from measures of BMI and age

An Actor-Based Model of Social Network Influence on Adolescent Body Size, Screen Time, and Playing Sports

Recent studies suggest that obesity may be “contagious” between individuals in social networks. Social contagion (influence), however, may not be identifiable using traditional statistical approaches because they cannot distinguish contagion from homophily (the propensity for individuals to select friends who are similar to themselves) or from shared environmental influences. In this paper, we apply the stochastic actor-based model (SABM) framework developed by Snijders and colleagues to data on adolescent body mass index (BMI), screen time, and playing active sports. Our primary hypothesis was that social influences on adolescent body size and related behaviors are independent of friend selection. Employing the SABM, we simultaneously modeled network dynamics (friendship selection based on homophily and structural characteristics of the network) and social influence. We focused on the 2 largest schools in the National Longitudinal Study of Adolescent Health (Add Health) and held the school environment constant by examining the 2 school networks separately (N = 624 and 1151). Results show support in both schools for homophily on BMI, but also for social influence on BMI. There was no evidence of homophily on screen time in either school, while only one of the schools showed homophily on playing active sports. There was, however, evidence of social influence on screen time in one of the schools, and playing active sports in both schools. These results suggest that both homophily and social influence are important in understanding patterns of adolescent obesity. Intervention efforts should take into consideration peers’ influence on one another, rather than treating “high risk” adolescents in isolation

Protocol for the modeling the epidemiologic transition study: a longitudinal observational study of energy balance and change in body weight, diabetes and cardiovascular disease risk.

BACKGROUND: The prevalence of obesity has increased in societies of all socio-cultural backgrounds. To date, guidelines set forward to prevent obesity have universally emphasized optimal levels of physical activity. However there are few empirical data to support the assertion that low levels of energy expenditure in activity is a causal factor in the current obesity epidemic are very limited. METHODS/DESIGN: The Modeling the Epidemiologic Transition Study (METS) is a cohort study designed to assess the association between physical activity levels and relative weight, weight gain and diabetes and cardiovascular disease risk in five population-based samples at different stages of economic development. Twenty-five hundred young adults, ages 25-45, were enrolled in the study; 500 from sites in Ghana, South Africa, Seychelles, Jamaica and the United States. At baseline, physical activity levels were assessed using accelerometry and a questionnaire in all participants and by doubly labeled water in a subsample of 75 per site. We assessed dietary intake using two separate 24-hour recalls, body composition using bioelectrical impedance analysis, and health history, social and economic indicators by questionnaire. Blood pressure was measured and blood samples collected for measurement of lipids, glucose, insulin and adipokines. Full examination including physical activity using accelerometry, anthropometric data and fasting glucose will take place at 12 and 24 months. The distribution of the main variables and the associations between physical activity, independent of energy intake, glucose metabolism and anthropometric measures will be assessed using cross-section and longitudinal analysis within and between sites. DISCUSSION: METS will provide insight on the relative contribution of physical activity and diet to excess weight, age-related weight gain and incident glucose impairment in five populations' samples of young adults at different stages of economic development. These data should be useful for the development of empirically-based public health policy aimed at the prevention of obesity and associated chronic diseases.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Complexity and Expressivity of Branching- and Alternating-Time Temporal Logics with Finitely Many Variables

We show that Branching-time temporal logics CTL and CTL*, as well as Alternating-time temporal logics ATL and ATL*, are as semantically expressive in the language with a single propositional variable as they are in the full language, i.e., with an unlimited supply of propositional variables. It follows that satisfiability for CTL, as well as for ATL, with a single variable is EXPTIME-complete, while satisfiability for CTL*, as well as for ATL*, with a single variable is 2EXPTIME-complete,--i.e., for these logics, the satisfiability for formulas with only one variable is as hard as satisfiability for arbitrary formulas.Comment: Prefinal version of the published pape

Kidney disease and the cumulative burden of life course socioeconomic conditions: The Atherosclerosis Risk in Communities (ARIC) Study.

The authors investigated the cumulative effects of life course social class and neighborhood socioeconomic conditions on the prevalence of chronic kidney disease (CKD) in adulthood. Subjects were members of the Atherosclerosis Risk in Communities (ARIC) Study, a longitudinal cohort study of four US communities. CKD was defined by glomerular filtration rate <45ml/min/1.73m(2) or hospital discharge diagnosis. Working class was defined by workplace roles for subjects and their fathers; area socioeconomic status (SES) was based on census information. Being working class for all life course periods or for some life course periods was associated with increased odds of CKD, compared to being non-working class for all periods (adjusted odds ratio, OR, for all periods (95% confidence interval) 1.4 (0.9, 2.0) in Whites and 1.9 (1.3, 2.9) in African-Americans; OR for some periods 1.3 (1.0, 1.9) in Whites and 1.4 (0.9, 2.2) in African-Americans). Low area SES over the life course was not significantly related to CKD compared to living in a higher SES areas at all life course periods. Adjustment for age, gender, community of residence, cumulative social class (for neighborhood measures), cumulative low-neighborhood SES (for cumulative individual social class), hypertension and diabetes does not account for these associations. Our conclusion is that chronic kidney disease is associated with life course socioeconomic conditions. As such, life course social class and neighborhood conditions deserve further attention in accounting for socioeconomic disparities in kidney disease.http://deepblue.lib.umich.edu/bitstream/2027.42/60950/1/Kidney disease and the cumalive burden of life course socioeconomic conditions - The ARIC study.pd

Distribution of metals exposure and associations with cardiometabolic risk factors in the “Modeling the Epidemiologic Transition Study”

Background: Metals are known endocrine disruptors and have been linked to cardiometabolic diseases via multiple potential mechanisms, yet few human studies have both the exposure variability and biologically-relevant phenotype data available. We sought to examine the distribution of metals exposure and potential associations with cardiometabolic risk factors in the “Modeling the Epidemiologic Transition Study” (METS), a prospective cohort study designed to assess energy balance and change in body weight, diabetes and cardiovascular disease risk in five countries at different stages of social and economic development. Methods: Young adults (25–45 years) of African descent were enrolled (N = 500 from each site) in: Ghana, South Africa, Seychelles, Jamaica and the U.S.A. We randomly selected 150 blood samples (N = 30 from each site) to determine concentrations of selected metals (arsenic, cadmium, lead, mercury) in a subset of participants at baseline and to examine associations with cardiometabolic risk factors. Results: Median (interquartile range) metal concentrations (μg/L) were: arsenic 8.5 (7.7); cadmium 0.01 (0.8); lead 16.6 (16.1); and mercury 1.5 (5.0). There were significant differences in metals concentrations by: site location, paid employment status, education, marital status, smoking, alcohol use, and fish intake. After adjusting for these covariates plus age and sex, arsenic (OR 4.1, 95% C.I. 1.2, 14.6) and lead (OR 4.0, 95% C.I. 1.6, 9.6) above the median values were significantly associated with elevated fasting glucose. These associations increased when models were further adjusted for percent body fat: arsenic (OR 5.6, 95% C.I. 1.5, 21.2) and lead (OR 5.0, 95% C.I. 2.0, 12.7). Cadmium and mercury were also related with increased odds of elevated fasting glucose, but the associations were not statistically significant. Arsenic was significantly associated with increased odds of low HDL cholesterol both with (OR 8.0, 95% C.I. 1.8, 35.0) and without (OR 5.9, 95% C.I. 1.5, 23.1) adjustment for percent body fat. Conclusions: While not consistent for all cardiometabolic disease markers, these results are suggestive of potentially important associations between metals exposure and cardiometabolic risk. Future studies will examine these associations in the larger cohort over time

Revisiting the spectrum of bladder health: Relationships between lower urinary tract symptoms and multiple measures of well-being

Background: Little research to date has investigated the spectrum of bladder health in women, including both bladder function and well-being. Therefore, we expanded our previous baseline analysis of bladder health in the Boston Area Community Health (BACH) Survey to incorporate several additional measures of bladder-related well-being collected at the 5-year follow-up interview, including one developed specifically for women. Methods: At follow-up, participants reported their frequency of 15 lower urinary tract symptoms (LUTS), degree of life impact from and thought related to urinary symptoms or pelvic/bladder pain/discomfort, and perception of their bladder condition. Prevalence ratios were calculated by generalized linear models with robust variance estimation, adjusting for LUTS risk factors and individual LUTS. The BACH Survey was approved by the New England Research Institutes Institutional Review Board and all participants provided written informed consent. Results: Generally similar findings were observed in the 5-year cross-sectional analysis as at baseline, irrespective of how we categorized LUTS or measured bladder-related well-being. Approximately one in five women (16.2%-18.0% of 2527 eligible women) reported no LUTS and no diminished bladder-related well-being, the majority (55.8%-65.7%) reported some LUTS and/or diminished well-being, and a further one in five (16.9%-26.6%) reported the maximum frequency, number, or degree of LUTS and/or diminished well-being. Measures of storage function (urinating again after &lt;2 hours, perceived frequency, nocturia, incontinence, and urgency) and pain were independently associated with bladder-related well-being. Conclusions: Our similar distribution of bladder health and consistent associations between LUTS and bladder-related well-being across multiple measures of well-being, including a female-specific measure, lend confidence to the concept of a bladder health spectrum and reinforce the bothersome nature of storage dysfunction and pain

Sugar-sweetened soda consumption, hyperuricemia, and kidney disease

The metabolism of high-fructose corn syrup used to sweeten soda drinks may lead to elevations in uric acid levels. Here we determined whether soda drinking is associated with hyperuricemia and, as a potential consequence, reduced kidney function. At baseline, 15,745 patients in the Atherosclerosis Risk in Communities Study completed a dietary questionnaire and had measurements of their serum creatinine and uric acid. After 3 and 9 years of follow-up, multivariate odds ratios from logistic regressions for binary outcome of hyperuricemia and chronic kidney disease (eGFR less than 60 ml/min per 1.73 m2) were evaluated. Compared to participants who drank less, consumption of over one soda per day was associated with increased odds of prevalent hyperuricemia and chronic kidney disease. The odds ratio for chronic kidney disease significantly increased to 2.59 among participants who drank more than one soda per day and had a serum uric acid level over 9.0 mg/dl. In longitudinal analyses, however, drinking more than one soda per day was not associated with hyperuricemia or chronic kidney disease. Neither preexistent hyperuricemia nor development of hyperuricemia modified the lack of association between soda drinking and incident chronic kidney disease. Thus our study shows that high consumption of sugar-sweetened soda was associated with prevalent but not incident hyperuricemia and chronic kidney disease