Sandra Cristina Pereira Costa Fuchs

Meta-analyses and Forest plots using a microsoft excel spreadsheet: step-by-step guide focusing on descriptive data analysis

BackgroundMeta-analyses are necessary to synthesize data obtained from primary research, and in many situations reviews of observational studies are the only available alternative. General purpose statistical packages can meta-analyze data, but usually require external macros or coding. Commercial specialist software is available, but may be expensive and focused in a particular type of primary data. Most available softwares have limitations in dealing with descriptive data, and the graphical display of summary statistics such as incidence and prevalence is unsatisfactory. Analyses can be conducted using Microsoft Excel, but there was no previous guide available.FindingsWe constructed a step-by-step guide to perform a meta-analysis in a Microsoft Excel spreadsheet, using either fixed-effect or random-effects models. We have also developed a second spreadsheet capable of producing customized forest plots.ConclusionsIt is possible to conduct a meta-analysis using only Microsoft Excel. More important, to our knowledge this is the first description of a method for producing a statistically adequate but graphically appealing forest plot summarizing descriptive data, using widely available software.

Postnatal depression in Southern Brazil: prevalence and its demographic and socioeconomic determinants.

BackgroundStudies investigating the prevalence of postnatal depression (PND) show rates ranging from 5% to 36.7%. The investigation of age, race, educational levels, religion and income as risk factors for PND has yielded conflicting results. The aim of this study is to investigate the prevalence of PND in women residing in Southern Brazil and the associated risk factors.MethodsThis is population-based cross-sectional study of women residing in Porto Alegre who delivered in June 2001. A sample of 271 participants were selected from the Record of Living Newborn Infants of the State Health Department (the official Brazilian database and stores the name and address of all women who give birth to living newborn infants) using a process based on pseudo-random numbers which choose a random sample from 2.000 records. Once the addresses were identified, the women were visited at their place of residence (home, hotel, boarding house and prison), with the interviews taking place between the 6th and the 8th week after delivery.The association between the risk factors and PND was investigated through bivariate analysis using Pearsons chi-square test. Students t-test was used to analyze the continuous variables. To identify independent risk factors, multivariate analysis was performed using hierarchical levels with a predefined model that took into account the time relationship between PND and the risk factors. Coxs regression was used to calculate the prevalence ratios.ResultsThe PND prevalence rate found was 20.7% (CI 95% 15.7 – 25.7). After adjusting for confounding variables, per capita income was found to have a significant association with PND.ConclusionThe prevalence of PND is higher than the figures found in most developed countries and similar to the figures found in developing countries. Differences in PND by regions or countries can be partially explained by the effect of income on the mediation of risk factors. In low income populations, women should be routinely evaluated for postnatal depression, and those with no partner or spouse are likely to require further care from health services and should be given the benefit of mental health prevention programs.

Epidemiology of leisure-time physical activity: a population-based study in southern Brazil

We aimed to measure the prevalence of physical inactivity (PI) during leisure time and to identify variables associated with it in a southern Brazilian adult population. A population-based cross-sectional study was carried out, covering a multiple-stage sample of 1,968 subjects aged 20-69 years. Weekly participation in leisure-time physical activity was addressed. For each activity, energy expenditure was calculated using data on duration, metabolic equivalent, and body weight. Energy expenditures of individual activities were summed to give a weekly total. PI was defined as fewer than 1,000 kilocalories per week. The prevalence of PI was 80.7% (95%CI: 78.9-82.4). After adjusted analyses, the following variables were positively associated with the outcome: female gender, age, living with a partner, and smoking. Schooling and economic status were inversely associated with PI. Chronically undernourished individuals were significantly more likely to be inactive. We found no differences according to skin color or alcohol consumption. In conclusion, the prevalence of PI in this adult population was higher than in populations from developed countries, but the associated variables were similar.

Nutritional status of pregnant women: prevalence and associated pregnancy outcomes

INTRODUCTION Although obesity is well recognized as a current public health problem, its prevalence and impact among pregnant women have been less investigated in Brazil. The objective of the study was to evaluate the impact of pre-obesity and obesity among pregnant women, describing its prevalence and risk factors, and their association with adverse pregnancy outcomes. METHODS A cohort of 5,564 pregnant women, aged 20 years or more, enrolled at approximately 20 to 28 weeks of pregnancy, seen in prenatal public clinics of six state capitals in Brazil were followed up, between 1991 and 1995. Prepregnancy weight, age, educational level and parity were obtained from a standard questionnaire. Height was measured in duplicate and the interviewer assigned the skin color. Nutritional status was defined using body mass index (BMI), according to World Health Organization (WHO) criteria. Odds ratios and 95% confidence interval were calculated using logistic regression. RESULTS Age-adjusted prevalences (and 95% CI) based on prepregnancy weight were: underweight 5.7% (5.1%-6.3%), overweight 19.2% (18.1%-20.3%), and obesity 5.5% (4.9%-6.2%). Obesity was more frequently observed in older black women, with a lower educational level and multiparous. Obese women had higher frequencies of gestational diabetes, macrosomia, hypertensive disorders, and lower risk of microsomia. CONCLUSIONS Overweight nutritional status (obesity and pre-obesity) was seen in 25% of adult pregnant women and it was associated with increased risk for several adverse pregnancy outcomes, such as gestational diabetes and pre-eclampsia.

Association between menopause status and central adiposity measured at different cutoffs of waist circumference and waist-to-hip ratio

Objective: To assess the association between menopause status and central adiposity measured using two different cutoffs of waist circumference and waist-to-hip ratio, while controlling for body mass index and other confounding factors. Design: Cross-sectional study of a representative population-based sample of 358 women from Passo Fundo, Southern Brazil. Medical students performed standardized interviews and anthropometric measurements under supervision. Menopause status was categorized as premenopausal for those with no change in menstrual frequency or flow; menopause transition for those who had these changes; and postmenopausal after 12 months of amenorrhea or bilateral oophorectomy. Obesity was defined by body mass index (BMI) equal or greater than 30 kg/m2, whereas central adiposity was defined as a waist circumference equal or greater than 80 or 88 cm and a waist-to-hip-ratio equal or greater than 0.80 or 0.86. Results: The anthropometric assessment showed that compared with postmenopausal women, premenopausal women were taller, had a thinner waist circumference, and had a lower waist-to-hip ratio. Postmenopausal women had five times the chance of having central adiposity than premenopausal women, even after controlling for BMI and other confounding factors. Women in the menopause transition had an increased BMI, but there was no independent association with central obesity. Conclusion: Postmenopausal women are at greater risk of central adiposity as detected by both waist circumference and waist-to-hip ratio.

Migraine is more frequent in individuals with optimal and normal blood pressure: a population-based study

Background The notion that hypertension causes headache is widely accepted despite the absence of confirmation by well-designed studies. Objective To investigate the association between headache, characterized as tension type and migraine like, with blood pressure and hypertension. Methods In a cross-sectional study we evaluate this association in a sample of 1174 individuals older than 17 years, representative of inhabitants of Porto Alegre, RS, Brazil. Headache and its subtypes were defined according to International Headache Society criteria. Hypertension was defined as the mean of two blood pressure readings ⩾140/90 mmHg or use of antihypertensive drugs. Results Headache in lifetime, in the last year, and defined as episodic and chronic tension-type headache was not associated with hypertension. Individuals with optimal or normal blood pressure (Sixth Joint National Committee criteria) complained of migraine more frequently than the participants with high-normal blood pressure or hypertension. This association persisted after adjustment for several potential confounding factors (risk ratio, 0.56; confidence interval, 0.41–0.77). Conclusion Our findings confirm that high blood pressure is not associated with the complaint of headache in the population. Individuals with migraine-like episodes of headache may have lower blood pressure than individuals without headache.

Prevalência de hipertensão arterial em adultos e fatores associados: um estudo de base populacional urbana em Pelotas, Rio Grande do Sul, Brasil

OBJECTIVE: To determine hypertension prevalence and its associated risk factors. METHODS: A cross-sectional, population-based study of people ages 20 to 69 living in the urban area of Pelotas, Rio Grande do Sul, Brazil, was conducted. The dependent variable systemic hypertension was defined as blood pressure >160 x 95 mm Hg (average of two readings) or current use of antihypertensive drugs. RESULTS: Among the 1,968 subjects enrolled in the study, hypertension prevalence was 23.6% (95% CI 21.6 to 25.3). A Poisson regression model was used to control confounding factors effects. The following variables remained statistically significant in the final model: family income, age, skin color, gender, family history of hypertension, extra salt intake, and body mass index. CONCLUSION: Compared with a similar study undertaken in 1992, hypertension prevalence increased, particularly in the younger groups.

Diagnosis of Obstructive Sleep Apnea Syndrome and Its Outcomes With Home Portable Monitoring

BACKGROUND The use of portable respiratory monitoring (PM) has been proposed for the diagnosis of obstructive sleep apnea syndrome (OSAS), but most studies that validate PM accuracy have not followed the best standards for diagnostic test validation. The objective of the present study was to evaluate the accuracy of PM performed at home to diagnose OSAS and its outcomes after first validating PM in the laboratory setting by comparing it to polysomnography (PSG). METHODS Patients with suspected OSAS were submitted, in random order, to PM at the sleep laboratory concurrently with PSG (lab-PM) or at home-PM. The diagnostic performance was assessed by sensitivity, specificity, positive and negative predictive values, positive likelihood ratio (+LR), negative likelihood ratio (-LR), intraclass correlation coefficients, kappa statistic, and Bland-Altman plot. RESULTS One hundred fifty-seven subjects (73% men, mean age +/- SD, 45 +/- 12 yr) with an apnea-hypopnea index (AHI) of 31 (SD +/- 29) events/h were studied. Excluding inadequate recordings, 149 valid comparisons with lab-PM and 121 with unattended home-PM were obtained. Compared to PSG for detecting AHI > 5, the lab-PM demonstrated sensitivity of 95.3%, specificity of 75%, +LR of 3.8, and -LR of 0.11; the home-PM exhibited sensitivity of 96%, specificity of 64%, +LR of 2.7, and -LR of 0.05. Kappa statistics indicated substantial correlation between PSG and PM results. Bland-Altman plot showed smaller dispersion for lab-PM than for home-PM. Pearson product moment correlation coefficients among the three AHIs and clinical outcomes were similar, denoting comparable diagnostic ability. CONCLUSIONS This study used all available comparison methods to demonstrate accuracy of PM in-home recordings similar to that of repeated PSGs. PM increases the possibility of correctly diagnosing and effectively treating OSAS in populations worldwide.

Aerobic exercise and submaximal functional capacity in overweight pregnant women: a randomized trial.

Objective: To evaluate the effects of aerobic training on submaximal cardiorespiratory capacity in overweight pregnant women. Methods: We conducted a randomized clinical trial in a referral center prenatal clinic during the period 2000–2002. Of 132 overweight (body mass index 26–31 kg/m2) but otherwise healthy volunteers, at 20 years of age or older, with gestational age of 20 weeks or less, and without diabetes or hypertension, 92 consented to participate and were randomized. Intervention consisted of 3 one-hour aerobic exercise sessions per week; the control group received weekly relaxation and focus group discussions. The main outcome measure was submaximal exercise capacity evaluated by oxygen uptake at the anaerobic (first ventilatory) threshold during cardiopulmonary treadmill testing 12 weeks after randomization. Results: Oxygen uptake at the anaerobic threshold increased 18% (15.9 ± 2.6 to 18.1 ± 3.1 mL · min−1 · kg−1) in the exercise group but decreased 16% (16.9 ± 3.0 to 15.8 ± 2.6 mL · min−1 · kg−1) among the control group. Oxygen consumption at the anaerobic threshold, adjusted through analysis of covariance for baseline oxygen uptake, was 2.68 (95% confidence interval 1.23 to 4.12) mL · min−1 · kg−1 greater in the exercise group. Women in the exercise group were approximately 5 times more likely than those in the control group to have regular or good cardiorespiratory capacity (12/38 versus 2/38; relative risk 5.2, 95% confidence interval 1.2 to 22.0, number needed to treat 5). Conclusion: Aerobic training in overweight pregnant women substantially increases submaximal exercise capacity, overcoming the otherwise negative effects of pregnancy in this regard. Additional studies are required to evaluate its effect on major clinical outcomes. LEVEL OF EVIDENCE: I

Metabolic syndrome prevalence is increased in rheumatoid arthritis patients and is associated with disease activity

Objectives: To evaluate the prevalence of metabolic syndrome (MetS) in patients with rheumatoid arthritis (RA) vs. controls, and to verify possible associations of MetS with specific disease-related factors. Methods: The subjects were 283 RA patients and 226 healthy controls, frequency matched by age and sex. MetS was defined according to National Cholesterol Education Program (NCEP) criteria. Disease activity was evaluated with the Disease Activity Score using 28 joints (DAS28). A standardized clinical evaluation was performed and cardiovascular risk factors were assessed. Results: The criteria for MetS were met by 39.2% RA patients vs. 19.5% in the control group (p < 0.001). Increased waist circumference, elevated blood pressure (BP), and fasting glucose were more frequent in RA patients than controls (p < 0.001 for all associations). By multiple logistic regression analysis (adjusted for age, sex, and years at school), the risk of having MetS was significantly higher for RA patients than for controls [odds ratio (OR) 1.87, 95% confidence interval (CI) 1.17–3.00, p = 0.009]. The DAS28 was significantly higher in RA patients with MetS than in those without MetS (3.59 ± 1.27 vs. 3.14 ± 1.53; p = 0.01). Disease duration, the presence of rheumatoid factor, and extra-articular manifestations were similar for patients with and without MetS. Conclusions: MetS frequency was higher in RA patients than in controls. Among RA patients, MetS was associated with disease activity. The higher prevalence of cardiovascular risk factors in RA suggests that inflammatory processes play a notable role in the development of cardiovascular disease (CVD), and indicates that tight control of systemic inflammatory activity and CVD modifiable risk factors should be recommended.