Handling random errors and biases in methods used for short-term dietary assessment

Epidemiological studies have shown the effect of diet on the incidence of chronic diseases; however, proper planning, designing, and statistical modeling are necessary to obtain precise and accurate food consumption data. Evaluation methods used for short-term assessment of food consumption of a population, such as tracking of food intake over 24h or food diaries, can be affected by random errors or biases inherent to the method. Statistical modeling is used to handle random errors, whereas proper designing and sampling are essential for controlling biases. The present study aimed to analyze potential biases and random errors and determine how they affect the results. We also aimed to identify ways to prevent them and/or to use statistical approaches in epidemiological studies involving dietary assessments

Stressful life events and current psychological distress are associated with self-reported hypertension but not with true hypertension: results from a cross-sectional population-based study

<p>Abstract</p> <p>Background</p> <p>The evidence linking stress to hypertension has been scarcely documented in population-based studies.</p> <p>Methods</p> <p>Participants were selected through a multi-stage probability sampling and interviewed at home, being submitted to measures of demographics, anthropometrics, blood pressure (BP), and risk factors for hypertension. Hypertension was defined as BP ≥ 140/90 mm Hg or use of BP-lowering drugs or as self-reported hypertension. Stressful life events were investigated through an inventory of nine major life events occurring in the year preceding the interview. Psychological distress was evaluated through a facial scale of expression of emotion in the last month.</p> <p>Results</p> <p>In the total, 1,484 adult individuals were investigated. Prevalence of hypertension was lower in individuals who reported any stressful life event in comparison with individuals who did not reported an event (34.3 versus 44.2%, P < 0.01), such as relative or friend death, loss of job, divorce, violence and migration. There was a trend for higher prevalence of hypertension in individuals with higher psychological distress in the last month, which was not longer significant after adjustment for confounding. In contrast, individuals who self-reported hypertension, but actually had normal blood pressure and were not using antihypertensive medication, reported higher numbers of stressful events.</p> <p>Conclusion</p> <p>Recent stressful life events and current psychological distress are not associated with hypertension. Associations between stress events and distress with self-reported hypertension are not intermediated by effects of stress on blood pressure, and may be ascribed to negative feeling about disease and not to the disease itself.</p

The Association between Socioeconomic Characteristics and Consumption of Food Items among Brazilian Industry Workers

Background. Dietary pattern plays a causative role in the rising of noncommunicable diseases. The SESI (Serviço Social da Indústria) study was designed to evaluate risk factors for noncommunicable diseases. We aimed to describe food items consumed by Brazilian workers and to assess their association with socioeconomic status. Methods. Cross-sectional study was carried out among Brazilian industrial workers, selected by multistage sampling, from 157 companies. Interviews were conducted at the work place using standardized forms. Results. 4818 workers were interviewed, aged 35.4 ± 10.7 years, 76.5% were men. The workers had an average of 8.7 ± 4.1 years of schooling and 25.4 ± 4.1 kg/m2 of BMI. Men and individuals with less than high school education were less likely to consume dairy products, fruits, and vegetables daily, even after control for confounding factors. Men consumed rice and beans daily more often than women. In comparison to workers aged 50–76 years, those under 30 years old consumed less fruits and green leafy vegetables daily. Conclusion. The food items consumed by Brazilian workers show that there are insufficient consumption according to the guidelines of healthy foods, particularly of dairy products, vegetables, and fruits

Shift Work Is Not Associated with High Blood Pressure or Prevalence of Hypertension

Background: Working mostly at night has been suggested to be associated with upset of chronobiological rhythms and high blood pressure, but the evidence from epidemiological studies is weak. Methods: In a cross-sectional survey, we evaluated the association between shift work and blood pressure, pre-hypertension and hypertension. In total, 493 nurses, nurse technicians and assistants, were selected at random in a large general hospital setting. Hypertension was diagnosed by the mean of four automatic blood pressure readings $140/ 90 mmHg or use of blood pressure lowering agents, and pre-hypertension by systolic blood pressure$120–139 or diastolic blood pressure $80–89 mmHg. Risk factors for hypertension were evaluated by a standardized questionnaire and anthropometric measurements. The association between the shift of work and blood pressure, pre-hypertension and hypertension was explored using univariate and multivariate analyses that controlled for risk factors for hypertension by covariance analysis and modified Poisson regression. Results: The mean age of the participants was 34.369.4 years and 88.2 % were women. Night shift workers were older, more frequently married or divorced, and less educated. The prevalence of hypertension in the whole sample was 16%, and 28% had pre-hypertension. Blood pressure (after adjustment for confounding) was not different in day and night shift workers. The prevalence of hypertension and pre-hypertension by shift work was not different in the univariate analysis and afte

Co-Infection by Hepatitis C Virus in HIV-Infected Patients in Southern Brazil: Genotype Distribution and Clinical Correlates

BACKGROUND: Prevalence rates of hepatitis C virus (HCV) co-infection, the distribution of HCV genotypes, and the frequency of spontaneous resolution of hepatitis C in patients infected with the Human Immunodeficiency Virus (HIV) have a worldwide disparity. The purpose of this study is to investigate the prevalence of HCV antibodies (anti-HCV) in patients with HIV, the proportion and correlates of infection by different HCV genotypes, and rates of spontaneous resolution of HCV infection. METHODS: A cross-sectional study was conducted among 1143 HIV patients under follow-up in a HIV/AIDS outpatient reference center of the Brazilian public health system. From 357 anti-HCV positive patients, a consecutive sample of 227 individuals HCV treatment-naïve was interviewed and 207 was tested for HCV-RNA and genotypes. RESULTS: Anti-HCV was detected in 357 patients (31.2%). HCV-RNA was undetectable in 16.4% of 207 anti-HCV positive individuals. Genotype 1 was diagnosed in 81.5% of the sample, genotype 2 in 1.7% and genotype 3 in 16.2%. Male gender was the unique characteristic associated with higher prevalence of genotype 1 HCV. CONCLUSIONS: Co-infection by HCV is frequent among patients with HIV in our State, and it is particularly high the infection by HCV genotype 1. Further investigation is necessary to explain the important regional variation in the proportion of infection by the different HCV genotypes and to better understand rates of spontaneous HCV clearance

Hypertension Management in Brazil: Usual Practice in Primary Care—A Meta-Analysis

Knowing the usual clinical practice is relevant for evaluations in health care and economic policies of management of hypertension. This study aimed to describe the usual management of hypertension in the Brazilian primary healthcare system through a systematic review and meta-analysis. The search of population-based studies conducted in Brazil was undertaken using PubMed, EMBASE, and Brazilian databases. Eligible studies were those conducted in adults with hypertension (blood pressure (BP) ≥ 140/90 mmHg or using BP lowering drugs). Three datasets’ data were analyzed: SESI study (in Brazilian workers); HIPERDIA (Brazilian Registration and Monitoring of Hypertensive and Diabetic Patients Program); and a population-based study. Meta-analysis has been performed using the fixed and random effect models. A total of 11 studies or data sets were included in the systematic review. Hypertensive individuals had, on average, 2.6 medical visits annually and 18.2% were on diuretics (n=811 hypertensive patients) and 16.2% on ACE inhibitors (n=1768 hypertensive patients). BP control rate ranged from 43.7 to 67.5%; 35.5% had measured total cholesterol and 36.5% determined fasting plasma glucose in the previous 12 months. Thiazide diuretics and ACE inhibitors were the most used BP lowering medications as single drugs, but the control rate of hypertension is insufficient

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions