Normal values of echocardiographic measurements. A population-based study

OBJECTIVE: To describe echocardiographic measurements and left ventricular mass in a population sample of healthy adults inhabitants of the urban region of Porto Alegre. METHODS: An analytical, observational, population-based, cross-sectional study was done. Through a multi-stage probability sample, 114 individuals were selected to be submitted to a M-mode and two-dimensional echocardiogram with color Doppler. The analyses were restricted to healthy participants. Echocardiographic measurements were described by mean, standard deviation, 95 percentile and 95% confidence limits. RESULTS: A total of 100 healthy participants, with several characteristics similar to those from the original population, had a complete and reliable echocardiographic examination. The measurements of aorta, left atrium, interventricular septum, left ventricle in systole and diastole, left posterior wall and left ventricular mass, adjusted or not for body surface area or height, were significantly higher in males. The right ventricle size was similar among the genders. Several echocardiographic measurements were within standard normal limits. Interventricular septum, left posterior wall and left ventricular mass, adjusted or not for anthropometric measurements, and aortic dimensions had lower mean and range than the reference limits. CONCLUSION: The means and estimates of distribution for the measurements of interventricular septum, left posterior wall and left ventricular mass found in this survey were lower than those indicated by the international literature and accepted as normal limits.

Mortality due to cardiovascular disease in women during the reproductive age (15 to 49 years), in the State of São Paulo, Brazil, from 1991 to 1995

OBJECTIVE: To describe mortality due to cardiovascular diseases in women during the reproductive age (15 to 49 years) in the state of São Paulo, Brazil, from 1991 to 1995. METHODS: A list of all deaths and their underlying causes, coded according to the International Classification of Diseases, 9th revision, multiple causes of death, and estimates of the female population according to age groups were provided by the SEADE Foundation. Specific coefficients for 100 thousand women for each year as well as the medians of these coefficients related to 5 years, and the percentage of death by subgroups were calculated. RESULTS: Cerebrovascular diseases have the highest coefficients (14.24 for 100 thousand females), followed by ischemic heart disease (7.37), other heart diseases (6.39), hypertensive disease (3.03), chronic rheumatic heart disease (1.58), pulmonary vascular diseases (1.29), and active rheumatic fever (0.05). Systemic arterial hypertension, as an associated cause, occurred in 55.3% to 57.8% of all the deaths due to intracerebral hemorrhage and in 30.4% to 30.8% due to subarachnoid hemorrhage. CONCLUSION: The significance of cerebrovascular diseases, coronary artery disease, and systemic arterial hypertension as causes of mortality suggests the need to emphasize preventive actions for young women who have the potential to reproduce to avoid possible complications in future pregnancies, and premature mortality.

Estimation of statistical cure from cancer using population-based data

Dissertação de mestrado em Estatística

Prevalence of hypertension in the urban population of Catanduva, in the State of São Paulo, Brazil

OBJECTIVE: To study the prevalence of systemic hypertension and its control in the population of Catanduva, in the state of São Paulo, Brazil. METHODS: We carried out a randomized cross-sectional population-based study of the urban population of Catanduva with individuals above 18 years of age (688 individuals accounting for 0.9% of the referred population). We interviewed study participants to analyze the major qualitative and quantitative variables that could influence the hypertensive scenario and the risk for systemic hypertension. Blood pressure was measured through the indirect method according to the III Consenso Brasileiro de Hipertensão (III Brazilian Consensus on Hypertension), which established blood pressure levels > or = 140/90 mm Hg as hypertensive. RESULTS: The prevalence of systemic hypertension was higher in individuals with: (1) history of hypertension (p<0.0001); (2) diabetes mellitus (p=0.05); (3) body mass index (B. M. I) > or = 25 kg/m² (p<0.001); (4) low educational level (p<0.0001); (5) familial income ranging from 1 to 5 minimum wages (p<0.05); (6) unmarried status (divorced/separated and widow(er)s) (p<0.0001). Of the interviewed individuals, 27.6% (p=0.05) had blood pressure levels under control. CONCLUSION: Our study showed that the prevalence of systemic hypertension was 31.5%, and that 27.6% of the individuals interviewed had blood pressure levels under control at the time of the interview.

Development of active bio-based multilayer systems: encapsulation of cinnamaldehyde and their physicochemical characterization

[Excerpt] In this work, different multilayer structures, using a polyhydroxybutyrate-co-valerate film with a valerate content of 8% (PHBV8) as support, were developed aiming the development of active bio-based multilayer systems. An interlayer based on zein nanofibers with and without cinnamaldehyde were electrospun in the PHBV8 film and three multilayer systems were developed: 1) without an outer layer; 2) using a PHBV8 film as outer layer; and 3) using an alginate-based film as outer layer. Their physico-chemical properties were evaluated through: water vapour and oxygen permeabilities and colour measurements, Fourier Transform Infrared Spectroscopy (FTIR) and thermal analyses. Results showed that the presence of different outer layers affected the water vapour permeability and transparency of the multilayer films. (...)

Some predictors of cardiovascular mortality among the elderly population of Botucatu (SP)

OBJECTIVE: To detect factors associated with cardiovascular mortality in the elderly of Botucatu. METHODS: We evaluated 29 variables of interest in a cohort of patients aged ³60 using data from a survey conducted between 1983/84. The elderly cohort was analyzed in 1992 to detect the occurrence of cardiovascular deaths. Survival analysis was performed using the Kaplan-Meier method, the log-rank test, and Cox regression analysis. Three models were adapted for each group of variables, and a final model was chosen from those variables selected from each group. RESULTS: We identified predictor for cardiovascular death according to age for elderly males not supporting the family, not possessing a vehicle, and previous cardiovascular disease. In elderly females, the predictor variables were previous cardiovascular disease and diabetes mellitus. CONCLUSION: Socioeconomic indicators (family heading and vehicle ownerrship) may be added to well stabilished medical factors (diabete mellitus and hypertension to select target groups for programs intended to reduce deaths due to cardiovascular diseases in elderly people.

The Bambuí health and aging study (BHAS). Prevalence of intermittent claudication in the aged population of the community of Bambuí and its associated factors

OBJECTIVE: To assess the prevalence of intermittent claudication in the aged population of Bambuí, Brazil, and to identify the factors associated with this disease. METHODS: Population-based cross-sectional study of the aged population ( > or = 60 years of age) of Bambuí. Participants were interviewed and examined, after written consent. Intermittent claudication was defined based on a standardized questionnaire. Analysis was performed using multiple logistic regression. RESULTS: Of the 1,742 elderly living in Bambuí, 1,485 (85.2%) were enrolled in the study. Thirty-seven individuals (2.5%) with intermittent claudication were identified: 28 (1.9%) males and 9 (0.6%) females. Their age brackets were: 16 (1.08%) individuals between 60 and 69 years of age, 17 (1.15%) between 70 and 79 years, and 4 (0.27%) > or = 80 years. A significant association between intermittent claudication and the following characteristics was found: male sex (OR=5.1; CI 2.4-11.0), smokers (OR=3.1; CI 1.2-8.5), ex-smokers (OR=3.4; CI 1.3-8.7), and more than 2 hospital admissions in the last 12 months (OR=2.8; CI 1.1-7.2). CONCLUSION: Disease prevalence was similar to that of other countries. The association between intermittent claudication and smoking strengthens the significance of tobacco in peripheral artery disease pathogenesis. The association of intermittent claudication and a higher number of hospital admissions suggests greater morbidity in the elderly affected.

Prevalence of Chagas' Disease in Mulungu do Morro Northeastern Brazil

OBJECTIVE - The aim of this paper is to describe the prevalence of T. Cruzi infection in patients of from Mulungu do Morro, a rural tropical region of Northeastern Brazil. METHODS - A cross-sectional study was performed. After randomly selecting samples of the population, and obtaining their consents , patients completed pretested epidemiological and clinical questionnaires. Serum samples from all patients were collected and screened for the presence of T. cruzi antibodies. RESULTS - Of 694 patients examined, 174 patients (25.1%) tested had a positive serology for Chagas' disease. Of the study population, 341 patients were male with 27% Chagas' disease prevalence, without a statistical difference. Illiteracy was the only variable related to T. cruzi infection in our population. CONCLUSION - In conclusion, our study points to the high prevalence of Chagas' disease among patients in Mulungu do Morro, suggesting that this region has a high frequency of infection and probably active vectorial transmission.

Analysis of the Association Between Apolipoprotein E Polymorphism and Cardiovascular Risk Factors in an Elderly Population with Longevity

OBJECTIVE: To establish the allelic and genotypic frequencies related to apolipoprotein E (ApoE) polymorphism and association of the genotypes with risk factors and cardiovascular morbidity in an elderly population with longevity. METHODS: We analyzed 70 elderly patients aged 80 years or more who were part of the Projeto Veranópolis. We used the gene amplification technique through the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and cleavage with the restriction enzyme Hha I to identify the ApoE genotypes. The most frequent genotypes were compared considering biological variables and cardiovascular risks and morbidity. RESULTS: The frequencies of the E2, E3, and E4 alleles were 0.05, 0.84, and 0.11, respectively, and of the genotypes were as follows: E3E3 (0.70), E3E4 (0.22), E2E3 (0.06), and E2E2 (0.02). Individuals with the E3E4 had a mean age greater than those with the E3E3. No association was observed between the genotypes and the variables analyzed, except for obesity, which was associated with the E3E3 genotype. Individuals with the E3E4 genotype had high levels of LDL-cholesterol and fibrinogen as compared with those with the E3E3 genotype. CONCLUSION: The results suggest that the E4E4 genotype may be associated with early mortality. A balance between the protective or neutral factors and the cardiovascular risk factors may occur among the individuals with different genotypes, attenuating the negative effects of the E4 allele.

Experimental validation of a proposed single-phase five-level active rectifier operating with model predictive current control

This paper presents a model predictive current control applied to a proposed single-phase five-level active rectifier (FLAR). This current control strategy uses the discrete-time nature of the active rectifier to define its state in each sampling interval. Although the switching frequency is not constant, this current control strategy allows to follow the reference with low total harmonic distortion (THDF). The implementation of the active rectifier that was used to obtain the experimental results is described in detail along the paper, presenting the circuit topology, the principle of operation, the power theory, and the current control strategy. The experimental results confirm the robustness and good performance (with low current THDF and controlled output voltage) of the proposed single-phase FLAR operating with model predictive current control.

Demographic characteristics of the population undergoing cine coronary angiography at the Instituto do Coração of the Medical School of USP from 1986 to 1995

OBJECTIVE: To obtain information about the profile and behavior of a population with ischemic heart disease undergoing cine coronary angiography and to determine disease severity. METHODS: Retrospective study assessing patients hospitalized at InCor from 1986 to 1995, in which the variables age, sex, and number of major coronary arteries with obstruction degree > 40% were analyzed. RESULTS: We studied 18,221 patients and observed a significant increase in the number of females (22.8% to 25.2%, P=0.001) and an increase in age (57.1±29.3 to 60.4±10.7 years, P=0.0001). A significant increase in the incidence of multivessel disease was observed, which was more frequent among males (69.2% and 64.5%) and among the older patients (59.8±9.8 and 56.8±10.7 years, P=0.0001). A reduction in the incidence of single-vessel disease was also observed (66.2% vs 69.2% and 33.8% vs 30.5%, respectively, P<0.0001). CONCLUSION: A change in the profile of the population studied was observed as follows: patients undergoing cine coronary angiography at InCor were older, had a greater number of impaired major coronary arteries, and the number of females affected increased, leading to indices suggestive of a poorer prognosis.