Asthma severity and impact on perinatal outcomes: an updated systematic review and meta-analysis.

BACKGROUND: Large-scale studies exploring the associations of asthma severity, exacerbations and medication use with adverse perinatal outcomes have been published in recent years. OBJECTIVES: To update evidence on the associations of asthma severity, exacerbations and medication use with the adverse perinatal outcomes of preterm delivery (PD), low birthweight (LBW) and small-for-gestational-age (SGA). SEARCH STRATEGY: PubMed, Embase, Wanfang, and China National Knowledge Infrastructure (CNKI) from inception to 1 January 2021. SELECTION CRITERIA: Cohort studies comparing the likelihood of adverse perinatal outcomes in groups of asthmatic women stratified by asthma severity, asthma exacerbations or medication use, or comparing the likelihood of adverse perinatal outcomes between non-asthmatic women and asthmatics of various levels of severity and exacerbation. DATA COLLECTION AND ANALYSIS: Two authors independently extracted data and assessed risk of bias. Random-effects models were used to meta-analyse the results. MAIN RESULTS: Twenty studies met the inclusion criteria. The odds of delivering SGA babies increased with maternal asthma severity. Pregnant women with an asthma exacerbation had higher odds of delivering LBW babies and SGA babies, compared with pregnant women with asthma but without an exacerbation (pooled adjusted odds ratio [OR] 1.15, 95% CI 1.02-1.29 for LBW; number of studies with adjusted OR 3; I2 = 0%) (pooled adjusted OR 1.13, 95% CI 1.04-1.23 for SGA; number of studies with adjusted OR 4; I2 = 0%) and compared to pregnant women without asthma. Oral corticosteroids use during pregnancy was associated with increased odds of LBW, but not PD. CONCLUSIONS: The available data suggest that maternal asthma severity and exacerbations are associated with increased odds of LBW and SGA babies. TWEETABLE ABSTRACT: A systematic review and meta-analysis found that maternal asthma severity and exacerbations are associated with increased odds of delivering low birthweight and small-for-gestational-age babies.

Early invasive versus conservative strategies for unstable angina & non-ST-elevation myocardial infarction in the stent era.

BACKGROUND: In patients with unstable angina and non-ST-elevation myocardial infarction (UA/NSTEMI) two strategies are possible: a routine invasive strategy where all patients undergo coronary angiography shortly after admission and, if indicated, coronary revascularization; or a conservative strategy where medical therapy alone is used initially with selection of patients for angiography based on clinical symptoms or investigational evidence of persistent myocardial ischemia. OBJECTIVES: To determine the benefits of an invasive compared to a conservative strategy for treating UA/NSTEMI in the stent era. SEARCH STRATEGY: The Cochrane Central Register of Controlled Trials (Issue 3 2005), MEDLINE and EMBASE were searched from 1996 to September 2005 with no language restrictions. SELECTION CRITERIA: Included studies were prospective trials comparing invasive with conservative strategies in UA/NSTEMI. DATA COLLECTION AND ANALYSIS: We identified 5 studies (7818 participants). Using intention-to-treat analysis with random effects models, summary estimates of relative risk (95% confidence interval [CI]) were determined for primary end-points of all-cause death, fatal and non-fatal myocardial infarction; all-cause death or non-fatal myocardial infarction; and refractory angina. Further analysis of included studies was undertaken based on whether glycoprotein IIb/IIIa receptor antagonists were used routinely. Heterogeneity was assessed using chi-square and variance (I(2)) methods. MAIN RESULTS: In the all-study analysis, mortality during initial hospitalization showed a trend to hazard with an invasive strategy; relative risk 1.59 (95% CI 0.96 to 2.64). Mortality and myocardial infarction assessed at 2-5 years in two trials were significantly decreased by an invasive strategy with relative risk of 0.75 (95% CI 0.62 to 0.92) and 0.75 (95% CI 0.61 to 0.91) respectively. The composite end-point of death or non-fatal myocardial infarction was significantly decreased by an invasive strategy at several time points after initial hospitalization. The incidence of early (<4 months) and intermediate (6-12 months) refractory angina were both significantly decreased by an invasive strategy; relative risk 0.47 (95% CI 0.32 to 0.68) and 0.67 (95% CI 0.55 to 0.83) respectively, as were early and intermediate rehospitalization rates with relative risk 0.60 (95% CI 0.41 to 0.88) and 0.67 (95% CI 0.61 to 0.74) respectively. The invasive strategy was associated with a two-fold increase in the relative risk of peri-procedural myocardial infarction (as variably defined) and a 1.7-fold increase in the relative risk of bleeding. AUTHORS' CONCLUSIONS: An early invasive strategy is preferable to a conservative strategy in the treatment of UA/NSTEMI.

Identifying studies for systematic reviews of diagnostic tests was difficult due to the poor sensitivity and precision of methodologic filters and the lack of information in the abstract.

BACKGROUND AND OBJECTIVES: Methods to identify studies for systematic reviews of diagnostic accuracy are less well developed than for reviews of intervention studies. This study assessed (1) the sensitivity and precision of five published search strategies and (2) the reliability and accuracy of reviewers screening the results of the search strategy. METHODS: We compared the results of the search filters with the studies included in two systematic reviews, and assessed the interobserver reliability of two reviewers screening the list of articles generated by a search strategy. RESULTS: In the first review, the search strategy published by van der Weijden had the greatest sensitivity, and in the second, four search strategies had 100% sensitivity. There was "substantial" agreement between two reviewers, but in the first review each reviewer working on their own would have missed one paper eligible for inclusion in the review. Ascertainment intersection techniques indicate that it is unlikely that further papers have been missed in the screening process. CONCLUSION: Published search strategies may miss papers for reviews of diagnostic test accuracy. Papers are not easily identified as studies of diagnostic test accuracy, and the lack of information in the abstract makes it difficult to assess the eligibility for inclusion in a systematic review.

Applying the results of a systematic review in general practice.

OBJECTIVE: To assess how general practitioners might interpret and apply the results of a systematic review relevant to general practice. DESIGN: Cross-sectional postal survey of general practitioners in August 1997. PARTICIPANTS: 51 general practitioners in the Southern Division of General Practice in Adelaide and 11 professors or heads of departments of general practice. MAIN OUTCOME MEASURES: Extent to which comments on the implications for practice and implications for research coincided with the evidence presented in a systematic review of antibiotics for the treatment of acute otitis media in children; and reported probability that respondents would prescribe antibiotics in three brief case scenarios. RESULTS: There was considerable variation in the comments made by general practitioners on the implications of the review for clinical practice. After reading the review, respondents with training in critical appraisal were more likely to state that children with acute otitis media would usually recover spontaneously and reported a lower probability of prescribing antibiotics in two of the three case scenarios. CONCLUSIONS: Providing systematic reviews is not sufficient for the results of such evidence to be translated into clinical practice. There is an association between critical appraisal skills and the application of evidence-based practice.

Patient desire for information before a total hip-replacement operation.

Patients who had been admitted to hospital in the Adelaide area for a total hip-replacement operation were questioned about the information that they wanted before their operation. The results showed that the majority of patients wanted to know about almost all aspects of their operation, including postoperative care. The major sources of information were the hospital doctors (surgeons, interns, and so on) who attended the patients. Doctors who regularly attended patients who were undergoing total hip-replacement operations also were surveyed in order to determine their perception of patients' desire for information; they underestimated significantly patients' wishes as indicated by the first survey. The implications of these findings for improvements in patient care are discussed.

Providing evidence-based answers to clinical questions. A pilot information service for general practitioners.

OBJECTIVE: To pilot a clinical information service for general practitioners. METHODS: A representative sample of 31 GPs was invited to submit clinical questions to a local academic department of general practice. Their views on the service and the usefulness of the information were obtained by telephone interview. RESULTS: Over one month, nine GPs (29% of the sample, 45% of those stating an interest), submitted 20 enquiries comprising 45 discrete clinical questions. The median time to search for evidence, appraise it and write answers to each enquiry was 2.5 hours (range, 1.0-7.4 hours). The median interval between receipt of questions and dispatch of answers was 3 days (range, 1-12 days). CONCLUSIONS: The GPs found the answers useful in clinical decision making; in four out of 20 cases patient management was altered.