Cardiovascular disease, risk factors and heart rate variability in the elderly general population: Design and objectives of the CARdiovascular disease, Living and Ageing in Halle (CARLA) Study

BACKGROUND: The increasing burden of cardiovascular diseases (CVD) in the ageing population of industrialized nations requires an intensive search for means of reducing this epidemic. In order to improve prevention, detection, therapy and prognosis of cardiovascular diseases on the population level in Eastern Germany, it is necessary to examine reasons for the East-West gradient of CVD morbidity and mortality, potential causal mechanisms and prognostic factors in the elderly. Psychosocial and nutritional factors have previously been discussed as possible causes for the unexplained part of the East-West gradient. A reduced heart rate variability appears to be associated with cardiovascular disease as well as with psychosocial and other cardiovascular risk factors and decreases with age. Nevertheless, there is a lack of population-based data to examine the role of heart rate variability and its interaction with psychosocial and nutritional factors regarding the effect on cardiovascular disease in the ageing population. There also is a paucity of epidemiological data describing the health situation in Eastern Germany. Therefore, we conduct a population-based study to examine the distribution of CVD, heart rate variability and CVD risk factors and their associations in an elderly East German population. This paper describes the design and objectives of the CARLA Study. METHODS/DESIGN: For this study, a random sample of 45–80 year-old inhabitants of the city of Halle (Saale) in Eastern Germany was drawn from the population registry. By the end of the baseline examination (2002–2005), 1750 study participants will have been examined. A multi-step recruitment strategy aims at achieving a 70 % response rate. Detailed information is collected on own and family medical history, socioeconomic, psychosocial, behavioural and biomedical factors. Medical examinations include anthropometric measures, blood pressure of arm and ankle, a 10-second and a 20-minute electrocardiogram, a general physical examination, an echocardiogram, and laboratory analyses of venous blood samples. On 200 participants, a 24-hour electrocardiogram is recorded. A detailed system of quality control ensures high data quality. A follow-up examination is planned. DISCUSSION: This study will help to elucidate pathways to CVD involving autonomic dysfunction and lifestyle factors which might be responsible for the CVD epidemic in some populations

Hydrologic variation during the last 170,000 years in the southern hemisphere tropics of South America

Despite the hypothesized importance of the tropics in the global climate system, few tropical paleoclimatic records extend to periods earlier than the last glacial maximum (LGM), about 20,000 years before present. We present a well-dated 170,000-year time series of hydrologic variation from the southern hemisphere tropics of South America that extends from modern times through most of the penultimate glacial period. Alternating mud and salt units in a core from Salar de Uyuni, Bolivia reflect alternations between wet and dry periods. The most striking feature of the sequence is that the duration of paleolakes increased in the late Quaternary. This change may reflect increased precipitation, geomorphic or tectonic processes that affected basin hydrology, or some combination of both. The dominance of salt between 170,000 and 140,000 yr ago indicates that much of the penultimate glacial period was dry, in contrast to wet conditions in the LGM. Our analyses also suggest that the relative influence of insolation forcing on regional moisture budgets may have been stronger during the past 50,000 years than in earlier times

Diagnostic and predictive values of circulating tetrahydrobiopterin levels as a novel biomarker in patients with thoracic and abdominal aortic aneurysms.

We have previously shown that circulating levels of tetrahydrobiopterin (H4B) function as a robust biomarker for aortic aneurysms in several independent animal models. In the present study, we examined diagnostic and predictive values of circulating H4B levels in human patients of thoracic aortic aneurysm (TAA) and abdominal aortic aneurysm (AAA) for the first time, while clinically applicable biomarkers for aortic aneurysms have never been previously available. Ninety-five patients scheduled for TAA repair surgeries and 53 control subjects were recruited at University of California Los Angeles (UCLA) Ronald Regan Medical Center, while 44 control subjects and 29 AAA patients were recruited through National Institute of Health (NIH) National Disease Research Interchange (NDRI) program. We had intriguing observations that circulating H4B levels were substantially lower in TAA and AAA patients, linearly correlated with aortic H4B levels (blood: R = 0.8071, p < 0.0001, n = 75; plasma: R = 0.7983, p < 0.0001, n = 75), and associated with incidence of TAA (blood: adjusted OR 0.495; 95% CI 0.379-0.647; p < 0.001; plasma: adjusted OR 0.501; 95% CI 0.385-0.652; p < 0.001) or AAA (blood: adjusted OR 0.329; 95% CI 0.125-0.868; p = 0.025) after adjustment for other factors. Blood or plasma H4B levels below 0.2 pmol/μg serve as an important threshold for prediction of aortic aneurysms independent of age and gender (for TAA risk - blood: adjusted OR 419.67; 95% CI 59.191-2975.540; p < 0.001; plasma: adjusted OR 206.11; 95% CI 40.956-1037.279; p < 0.001). This threshold was also significantly associated with incidence of AAA (p < 0.001 by Chi-square analysis). In addition, we observed previously unrecognized inverse association of Statin use with TAA, and an association of AAA with arrhythmia. Taken together, our data strongly demonstrate for the first time that circulating H4B levels can serve as a first-in-class, sensitive, robust and independent biomarker for clinical diagnosis and prediction of TAA and AAA in human patients, which can be rapidly translated to bedside to fundamentally improve clinical management of the devastating human disease of aortic aneurysms

Differences in Cardiovascular Disease Risk Factors by Weight History: The Aerobics Center Longitudinal Study

The objective of this study was to compare cardiovascular disease (CVD) risk factor levels in adults with a history of weight loss to levels in adults who did not lose weight, after both groups subsequently experienced an approximate 1-year interval of weight maintenance. Extant data from the Aerobics Center Longitudinal Study (ACLS) were used to identify 5,151 adults who were weight maintainers (maintained weight within ±3.0% over two consecutive periods of ~1 year) or weight-loss maintainers (lost >3.0–<5.0% or ≥5.0% of body weight in the first interval and maintained that loss in the second interval). Mixed models regression was used to accommodate repeated measures and adjust for gender, age, smoking, cardiorespiratory fitness, decade of clinic visit, interval length, and BMI at the time of risk factor measurement. Coefficients from the model were used to calculate the adjusted risk factor levels in the three groups. Differences in total cholesterol (−3.8 mg/dl, 95% confidence interval: −5.5, −2.0), low-density lipoprotein (LDL) cholesterol (−3.0 mg/dl, confidence interval: −4.8, −1.1), triglycerides (−6.1 mg/dl, confidence interval: −10.6, −1.7) and diastolic blood pressure (−0.8 mg/dl, confidence interval: −1.4, −0.3) indicated that levels were slightly more favorable in the ≥5.0% weight-loss maintenance group than weight maintenance group. Levels were similar for glucose, high-density lipoprotein (HDL) cholesterol and systolic blood pressure. This work indicates that, when adjusted for covariates including current BMI, adults with a history of weight loss may have CVD risk factors to levels as good, or perhaps even better than, those observed in adults who maintain their weight