Parental hyperdynamic circulation predicts insulin resistance in offspring: The Tecumseh Offspring Study.
(49/28941)
Controversy surrounds the pathogenetic mechanisms of the relationship between hyperdynamic circulation and insulin resistance. Two hundred eight children and young adults (mean age, 17.2+/-3.0 years; range, 11 to 26 years) from the Tecumseh Offspring Study whose parents had been assessed with Doppler echocardiography at the age of 34 years during the previous Tecumseh Blood Pressure Study were considered for this analysis. Offspring data were stratified according to tertiles of parental cardiac index. Parents in the top cardiac index tertile had increased heart rate (P=0.001), stroke volume (P=0.0001), left ventricular fractional shortening (P=0.02), and plasma epinephrine (P=0.02) compared with parents in the other tertiles. Body mass index (BMI) and blood pressure were similar in all groups. Offspring of parents with a high cardiac index had greater BMI (P=0.001), skinfold thickness (P=0.008), and waist/hip ratio (P=0.02), higher diastolic blood pressure (P=0.02) and plasma insulin level (P=0.001), and higher heart rate during Stroop's color test (P=0.02) than offspring of parents with a lower cardiac index. In a multivariate regression analysis, offspring BMI was predicted by parental BMI and cardiac index (P=0.0001 and 0.003, respectively). The mother-child relationship explained most of the cardiac index-BMI association. In summary, parental hyperdynamic circulation was an important predictor of overweight, abnormal fat distribution, increased blood pressure, and hyperinsulinemia in offspring. Our results illustrate the complexity of interaction between a genetic tendency and its phenotypic expression. We speculate that the degree of beta-adrenergic responsiveness may be a major determinant of the phenotypic differences between the parents and offspring found in this study. (+info)
Assessment of arterial compliance by carotid midwall strain-stress relation in normotensive adults.
(50/28941)
Examining left ventricular midwall as opposed to endocardial mechanics enhances understanding of left ventricular function in individuals with abnormal cardiac geometry. Accordingly, we used carotid ultrasound and applanation tonometry of arterial pressure to derive carotid midwall strain and its relation to carotid peak-systolic and end-diastolic stresses in 82 apparently normal, employed subjects (56 men, 26 women; median age, 47 years; 70% white; 21% overweight) with no evidence of coronary or valvular heart disease. Regression equations relating carotid luminal and midwall strain to the increment in carotid stress during systole (Deltacarotid stress) were used to predict strain for the observed Deltastress. Observed/predicted carotid luminal or midwall strain was calculated as a measure of carotid luminal or midwall strain for imposed stress, termed stress-corrected strain. Midwall carotid strain was similar in women and men but was negatively related to older age (r=-0.35, P=0.001) and higher body mass index (r=-0.31, P=0.005) and brachial and carotid blood pressure (r=-0.30 to -0.45, all P<0.01). The pulsatile change in arterial load, measured by Deltacarotid stress, was positively related to midwall strain (r=0. 44, P<0.001) more closely than was carotid luminal strain. Regression analyses revealed that carotid midwall strain was positively related to Deltastress, with additional negative relations to age and carotid diastolic diameter (all P<0.001). Stress-corrected carotid midwall strain was strongly and negatively correlated with midwall elastic modulus and Young's modulus (both r=-0.77, P<0.001), followed by elastic modulus (r=-0.74, P<0.001), midwall Young's modulus (r=-0.73, P<0.001), midwall stiffness index (r=-0.70, P<0.001), and stiffness index (r=-0.66, P<0.001). Thus, in normal adults, carotid midwall strain is unrelated to gender, is positively related to pulsatile carotid load as measured by Deltacarotid stress, and is negatively related to age, overweight, and standard measures of arterial stiffness. (+info)
Stroke volume/pulse pressure ratio and cardiovascular risk in arterial hypertension.
(51/28941)
Ratio of stroke volume (SV, M-mode echocardiography) to pulse pressure (PP) has been proposed as an estimate of total arterial compliance and has been shown to be related to body size, age, and heart rate in normal adults. SV/PP was estimated in 294 hypertensive patients (98 women) as a raw value by use of SV/body surface area (SVi) and by the ratio of SV/PP to the value predicted by a previously developed equation (%SV/PP). At baseline, the 50 patients who had cardiovascular events over the following 10 years exhibited higher PP and lower SV/PP, SVi/PP, and %SV/PP (all P<0.008) than patients without events. Crude risk of follow-up total and fatal cardiovascular events increased with increasing level of PP and decreasing SV/PP, SVi/PP, and %SV/PP (all P<0.002). In multivariate logistic regression models with continuous covariates, the risk of total cardiovascular events was independently related to increasing age (P<0.0001) and left ventricular (LV) mass index (P<0.003) and decreasing values of %SV/PP (P<0.006) but not to increasing systolic, pulse, or mean blood pressure or gender. Similar although less strong results were obtained with the use of SVi/PP (P<0.02), whereas SV/PP did not enter the model as an independent predictor. Risk of cardiovascular death was only predicted by age and LV mass index. The %SV/PP was also an independent predictor of total cardiovascular events in Cox proportional hazards analysis (exp[b]: 2.49, P<0.001) independent of age (exp[b]: 1.05, P<0.003) and LV mass index (exp[b]: 1.02, P<0.0003), whereas no effect was detected for height. Thus, in patients with arterial hypertension, a reduced ratio of M-mode echocardiographic SV/PP as a percentage of the value predicted by demographic variables is a predictor of cardiovascular morbid events independent of age and LV mass index. (+info)
Advances in the surgical techniques, preservation solutions, and methods for predicting eventual long-term renal function from expanded donors will be critical in allowing precise selection criteria for kidneys for transplantation, resulting in the optimum use of a scarce and precious resource. Until other options such as xenotransplantation or tissue engineering become realistic, the challenge for the millennium will be to identify which donor organs previously considered suboptimal can be safely used to expand the organ donor pool. (+info)
Changing trends in barriers to cataract surgery in India.
(53/28941)
Cataract is a major cause of blindness in Asia. Efforts in India to provide cataract surgical services have had limited success in reaching the cataract-blind population. Earlier studies identified the major barriers to cataract surgery as poverty, lack of transportation or felt need, or sex related; and the critical barriers in rural areas as lack of awareness, difficult access, and cost. Compared with these earlier data, the results of the present study in Karnataka State indicate a shift in the character of the barriers. They now appear to be more related to case selection and service provision. These shifts are analysed and alternative strategies to increase the uptake to cataract surgery are recommended. (+info)
Human echinococcosis in Bulgaria: a comparative epidemiological analysis.
(54/28941)
The present article describes the importance of human echinococcosis as a public health problem in Bulgaria, outlines the control measures carried out and evaluates comparatively the situation over three periods spanning 46 years (1950-1995). During the first period (1950-62), a total of 6469 new surgically confirmed cases of hydatid disease were recorded in Bulgaria, with an annual incidence of 6.5 per 100,000 population, and the infestation rate in domestic animals and dogs was high. Echinococcosis was endemic throughout the country. The organization of a control campaign, initiated in 1960, led to a considerable improvement in the situation during the second period (1971-82). Morbidity among humans gradually decreased, with an average incidence of 2.0 per 100,000, and the proportion of infected animals also fell. The distribution of echinococcosis was characterized as sporadic or of low endemicity. During the third period (1983-95), owing to administrative irregularities and economic changes, funds for supporting the campaign were reduced and control structures were dismantled. As a result, the incidence rose to 3.3 per 100,000. Echinococcosis again became endemic, in some regions hyperendemic. The findings provide convincing evidence that cessation of control measures or reduction of campaign activity can lead to intensification in the transmission of Echinococcus granulosus and to a resurgence in echinococcosis to previous levels. (+info)
Long-term morbidity and mortality following hypoxaemic lower respiratory tract infection in Gambian children.
(55/28941)
Acute lower respiratory infections (ALRI) are the main cause of death in young children worldwide. We report here the results of a study to determine the long-term survival of children admitted to hospital with severe pneumonia. The study was conducted on 190 Gambian children admitted to hospital in 1992-94 for ALRI who survived to discharge. Of these, 83 children were hypoxaemic and were treated with oxygen, and 107 were not. On follow-up in 1996-97, 62% were traced. Of the children with hypoxaemia, 8 had died, compared with 4 of those without. The mortality rates were 4.8 and, 2.2 deaths per 100 child-years of follow-up for hypoxaemic and non-hypoxaemic children, respectively (P = 0.2). Mortality was higher for children who had been malnourished (Z-score < -2) when seen in hospital (rate ratio = 3.2; 95% confidence interval (CI) = 1.03-10.29; P = 0.045). Children with younger siblings experienced less frequent subsequent respiratory infections (rate ratio for further hospitalization with respiratory illness = 0.15; 95% CI = 0.04-0.50; P = 0.002). Children in Gambia who survive hospital admission with hypoxaemic pneumonia have a good prognosis. Survival depends more on nutritional status than on having been hypoxaemic. Investment in oxygen therapy appears justified, and efforts should be made to improve nutrition in malnourished children with pneumonia. (+info)
Health expectancy indicators.
(56/28941)
An outline is presented of progress in the development of health expectancy indicators, which are growing in importance as a means of assessing the health status of populations and determining public health priorities. (+info)