The objective of this study is to assess and quantify the risk for gestational diabetes mellitus (GDM) according to prepregnancy maternal body mass index (BMI). The design is a systematic review of observational studies published in the last 30 years. Four electronic databases were searched for publications (1977-2007). BMI was elected as the only measure of obesity, and all diagnostic criteria for GDM were accepted. Studies with selective screening for GDM were excluded. There were no language restrictions. The methodological quality of primary studies was assessed. Some 1745 citations were screened, and 70 studies (two unpublished) involving 671 945 women were included (59 cohorts and 11 case-controls). Most studies were of high or medium quality. Compared with women with a normal BMI, the unadjusted pooled odds ratio (OR) of an underweight woman developing GDM was 0.75 (95% confidence interval [CI] 0.69 to 0.82). The OR for overweight, moderately obese and morbidly obese women were 1.97 (95% CI 1.77 to 2.19), 3.01 (95% CI 2.34 to 3.87) and 5.55 (95% CI 4.27 to 7.21) respectively. For every 1 kg m(-2) increase in BMI, the prevalence of GDM increased by 0.92% (95% CI 0.73 to 1.10). The risk of GDM is positively associated with prepregnancy BMI. This information is important when counselling women planning a pregnancy.

The whole findings of this systematic review are no more than suggestive of the superiority of early over late tracheostomy because no information of high quality is available for specific subgroups with particular characteristics.

Background Subclinical hypothyroidism is defined as an elevated serum thyroid-stimulating hormone (TSH) level with normal free thyroid hormones values. The prevalence of subclinical hypothyroidism is 4% to 8% in the general population, and up to 15% to 18% in women who are over 60 years of age. There is considerable controversy regarding the morbidity, the clinical significance of subclinical hypothyroidism and if these patients should be treated. Objectives To assess the effects of thyroid hormone replacement for subclinical hypothyroidism. Search methods We searched The Cochrane Library, MEDLINE, EMBASE and LILACS. Ongoing trials databases, reference lists and abstracts of congresses were scrutinized as well. Selection criteria All studies had to be randomised controlled trials comparing thyroid hormone replacement with placebo or no treatment in adults with subclinical hypothyroidism. Minimum duration of follow-up was one month. Data collection and analysis Two authors independently assessed trial quality and extracted data. We contacted study authors for missing or additional information. Main results Twelve trials of six to 14 months duration involving 350 people were included. Eleven trials investigated levothyroxine replacement with placebo, one study compared levothyroxine replacement with no treatment. We did not identify any trial that assessed (cardiovascular) mortality or morbidity. Seven studies evaluated symptoms, mood and quality of life with no statistically significant improvement. One study showed a statistically significant improvement in cognitive function. Six studies assessed serum lipids, there was a trend for reduction in some parameters following levothyroxine replacement. Some echocardiographic parameters improved after levothyroxine replacement therapy, like myocardial relaxation, as indicated by a significant prolongation of the isovolumic relaxation time as well as diastolic dysfunction. Only four studies reported adverse events with no statistically significant differences between groups.

No abstract

Objective. The purpose of this systematic review was to obtain summary estimates of the diagnostic accuracy of color Doppler ultrasonography (CDU) in predicting malignancy in thyroid follicular neoplasms (FNs). Methods. We searched Medical Subject Headings together with the search terms "follicular," "thyroid," and "Doppler" in the MEDLINE, Web of Science, and Excerpta Medica databases as well as the Latin American and Caribbean Health Sciences Literature database, after which we performed manual searches of the reference lists to locate additional studies. There were no language restrictions. We included studies that assessed the diagnostic accuracy of CDU in identifying malignancy in thyroid FNs. The assessments of the quality and extraction of data were performed by 3 independent reviewers. Results. We included 4 studies, which collectively evaluated 457 thyroid FNs, 67 of which had been classified as malignant based on the evaluation of surgical biopsy samples. Moderate, rich, predominant, or exclusive internal flow on CDU of thyroid FNs was considered indicative of malignancy. The overall sensitivity of CDU was 85% (95% confidence interval [CI], 74%-93%), with an overall specificity of 86% (95% CI, 82%-89%). The overall prevalence was 14.7%, and the positive and negative predictive values were 51% and 97%, respectively. The positive likelihood ratio was 6.07, and the negative likelihood ratio was 0.18. Conclusions. Predominant internal flow seen on CDU is associated with malignancy of thyroid FNs. Absence of internal flow or predominantly peripheral flow indicates a low probability of thyroid FN malignancy. Key words: color Doppler ultrasonography; fine-needle biopsy; follicular neoplasm. Medicine, Brazilian Cochrane Center, São Paulo, Brazil (W.I., J.C.C., R.A., A.N.A., O.V.) However, in studies using ultrasonography, the prevalence has been reported to be as high as 67%. 2 In autopsy findings, the prevalence of thyroid nodules is 50%. The most common thyroid malignant nodules are follicular epithelial cell-derived carcinomas: papillary carcinoma (75%-80%) or follicular carcinoma (10%-20%). These tumors are slow growing and, if treated, have a good prognosis. [4][5][6][7] Received July 14, 2009, from the Department of Internal

Updated evidence is of low quality, and potential differences between early and late tracheostomy need to be better investigated by means of randomized controlled trials. At present there is no specific information about any subgroup or individual characteristics potentially associated with better outcomes with either early or late tracheostomy.

No abstract

CONTEXT AND OBJECTIVE: Mammography is the best method for breast-cancer screening and is capable of reducing mortality rates. Studies that have assessed the clinical impact of mammography have been carried out using film mammography. Digital mammography has been proposed as a substitute for film mammography given the benefits inherent to digital technology. The aim of this study was to compare the performance of digital and film mammography. DESIGN: Systematic review and meta-analysis. METHOD: The Medline, Scopus, Embase and Lilacs databases were searched looking for paired studies, cohorts and randomized controlled trials published up to 2009 that compared the performance of digital and film mammography, with regard to cancer detection, recall rates and tumor characteristics. The reference lists of included studies were checked for any relevant citations. RESULTS: A total of 11 studies involving 190,322 digital and 638,348 film mammography images were included. The cancer detection rates were significantly higher for digital mammography than for film mammography (risk relative, RR = 1.17; 95% confidence interval, CI = 1.06-1.29; I² = 19%). The advantage of digital mammography seemed greatest among patients between 50 and 60 years of age. There were no significant differences between the two methods regarding patient recall rates or the characteristics of the tumors detected. CONCLUSION: The cancer detection rates using digital mammography are slightly higher than the rates using film mammography. There are no significant differences in recall rates between film and digital mammography. The characteristics of the tumors are similar in patients undergoing the two methods.