First Australian estimates of incidence and prevalence of uterine fibroids: a data linkage cohort study 2000-2022.

STUDY QUESTION: What is the estimated prevalence and incidence of uterine fibroids diagnosed in Australian women of reproductive age? SUMMARY ANSWER: An estimated 7.3% of Australian women had a diagnosis of uterine fibroids by the age of 45-49 years, with age-specific incidence highest in women aged 40-44 years (5.0 cases per 1000 person-years). WHAT IS KNOWN ALREADY: Uterine fibroids are associated with a high symptom burden and may affect overall health and quality of life. Studies in different countries show a wide variation in both the prevalence (4.5-68%) and incidence (2.2-37.5 per 1000 person-years) of uterine fibroids, which may be partly explained by the type of investigation, method of case ascertainment, or the age range of the study population, necessitating the reporting of country-specific estimates. STUDY DESIGN, SIZE, DURATION: This observational prospective cohort study using self-report survey and linked administrative data (2000-2022) included 8066 women, born between 1973 and 1978, in the Australian Longitudinal Study on Women's Health. PARTICIPANTS/MATERIALS, SETTING, METHODS: A combination of self-report survey and linked administrative health data (hospital, emergency department, the Medicare Benefits Schedule, and the Pharmaceutical Benefits Scheme) were used to identify women with a report of a diagnosis of uterine fibroids between 2000 and 2022. MAIN RESULTS AND THE ROLE OF CHANCE: Of the 8066 Australian women followed for 22 years, an estimated 7.3% of women (95% CI 6.9, 7.6) had a diagnosis of uterine fibroids by the age of 45-49 years. The incidence increased with age and was highest in women aged 40-44 years (5.0 cases per 1000 person-years, 95% CI 4.3, 5.7 cases per 1000 person-years). Women with uterine fibroids were more likely to experience heavy or painful periods. They were also more likely to report low iron levels, endometriosis, and poor self-rated health and to have two or more annual visits to their general practitioner. LIMITATIONS, REASONS FOR CAUTION: Our estimates are based on self-report of doctor diagnosis or treatment for fibroids and/or data linked to treatment and procedure administrative records. This predominantly captures women with symptomatic fibroids, but has the potential for misclassification of asymptomatic women and an underestimate of overall prevalence and incidence. In addition, questions on fibroids were only asked in surveys when women were 37-42 years of age to 43-48 years of age, so cases at younger ages may have been underestimated (particularly in women with less severe symptoms) as these were only ascertained through data linkage. WIDER IMPLICATIONS OF THE FINDINGS: These are the first population-based estimates of the prevalence and incidence of uterine fibroids in women of reproductive age in Australia. Establishing these first estimates will help inform health policy and health care provision in the Australian context. STUDY FUNDING/COMPETING INTEREST(S): The ALSWH is funded by the Australian Government Department of Health and Aged Care. L.FW. was supported by an Australian National Health and Medical Research Council (NHMRC) Centres for Research Excellence grant (APP1153420) and G.D.M. was supported by an NHMRC Leadership Fellowship (APP2009577). The funding bodies played no role in the design, the collection, analysis or interpretation of data, the writing of the manuscript, or the decision to submit the manuscript for publication. There are no competing interests. TRIAL REGISTRATION NUMBER: N/A.

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.

Delayed diagnosis of endometriosis disadvantages women in ART: a retrospective population linked data study.

STUDY QUESTION: Do the outcomes and use of ART differ between women with and without endometriosis? SUMMARY ANSWER: ART use and outcome do not appear to differ for women with and without endometriosis, as long as endometriosis is diagnosed prior to commencing ART. WHAT IS KNOWN ALREADY: Approximately 40% of women with endometriosis have infertility and ART is the recommended treatment option for these women. However, diagnosis of endometriosis can be complex and lengthy, and a delay in diagnosis can reduce the likelihood of achieving a live birth. STUDY DESIGN, SIZE, DURATION: This retrospective national cohort study used longitudinal self-report data (collected 1996-2018) from women born in 1973-1978 who are participants in the Australian Longitudinal Study on Women's Health (ALSWH). The study also used linked administrative data on Endometriosis (1970-2018), ART (1996-2020) and births (1996-2018). PARTICIPANTS/MATERIALS, SETTING, METHODS: The outcome measures were: age at first ART cycle; use of ART treatments (IVF only; IUI only/and IVF); number of ART cycles (1-3; 4-10; 11-36); and births after first ART (no; yes) (note that births could not be tied to ART). MAIN RESULTS AND THE ROLE OF CHANCE: One in three (34.7%, n = 459/1322) women using ART had endometriosis, with 65.6% of these diagnosed before first ART and 34.4% after. Adjusted regression analyses showed women with endometriosis diagnosed before first ART were not significantly different to women without endometriosis on any outcome. However, women with endometriosis diagnosed after first ART were more likely to use IUI (adjusted odds ratio (aOR) 2.14, 95% CI 1.48, 3.09) and do more cycles (11-36 cycles: aOR 4.09, 95% CI 2.41, 6.95), and less likely to report a birth (aOR 0.67, 95% CI 0.45, 0.99), compared to women without endometriosis, despite no significant difference in starting age (coefficient = -0.62, 95% CI -1.36, 0.13). LIMITATIONS, REASONS FOR CAUTION: We did not have information on the severity of endometriosis, or the reasons for using ART, which can influence treatment and outcomes. We were not able to reliably link births with ART treatment. Finally, it is possible that some of the women in our 'no endometriosis' group did have endometriosis and were unaware of it, although prevalence rates match population estimates. WIDER IMPLICATIONS OF THE FINDINGS: These findings support previous studies that have found no difference in outcome of ART for women with endometriosis, but add the new insight that this is only true if endometriosis is diagnosed prior to commencing ART. A delayed diagnosis can create disadvantage during ART treatment. Early recourse to IVF may be advantageous for pregnancy prospects for women with endometriosis. STUDY FUNDING/COMPETING INTEREST(S): The ALSWH is funded by the Australian Government Department of Health. G.D.M. is supported by an NHMRC Principal Research Fellowship (APP11218449). The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Clinicians' perspectives on diagnosing polycystic ovary syndrome in Australia: a qualitative study.

STUDY QUESTION: What are clinicians' views about the diagnosis of polycystic ovary syndrome (PCOS), and how do they handle any complexities and uncertainties in practice? SUMMARY ANSWER: Clinicians have to navigate many areas of complexity and uncertainty regarding the diagnosis of PCOS, related to the diagnostic criteria, limitations in current evidence and misconceptions surrounding diagnosis, and expressed concern about the risk and consequences of both under- and overdiagnosis. WHAT IS KNOWN ALREADY: PCOS is a complex, heterogeneous condition with many areas of uncertainty, raising concerns about both underdiagnosis and overdiagnosis. Quantitative studies with clinicians have found considerable variation in diagnostic criteria used and care provided, as well as a lack of awareness around the breadth of PCOS features and poor uptake of recommended screening for metabolic complications. Clinicians' views about the uncertainties and complexities of diagnosing PCOS have not been explored. STUDY DESIGN, SIZE, DURATION: Semi-structured telephone interviews were conducted with clinicians from September 2017 to July 2018 to explore their perceptions about the diagnosis of PCOS, including how they handle any complexities and uncertainties in practice. PARTICIPANTS/MATERIALS, SETTING, METHODS: A group of 36 clinicians (15 general practitioners, 10 gynaecologists and 11 endocrinologists) currently practicing in Australia, were recruited through advertising via professional organisations, contacting a random sample of endocrine and gynaecology teams across Australia and snowballing. Transcribed audio-recordings were analysed thematically using Framework analysis. MAIN RESULTS AND THE ROLE OF CHANCE: Clinicians expressed a range of uncertainties and complexities regarding the diagnosis of PCOS, which were organised into three areas: (i) establishing diagnosis (e.g. lack of standardisation regarding diagnostic cut-offs, risk of misdiagnosis), (ii) factors influencing the diagnostic process (e.g. awareness of limitations in evidence and consideration of the benefits and harms) and (iii) strategies for handling challenges and uncertainties (e.g. using caution and communication of uncertainties). Clinicians also varied in their concerns regarding under- and overdiagnosis. Overall, most felt the diagnosis was beneficial for women provided that it was the correct diagnosis and time was taken to assess patient expectations and dispel misconceptions, particularly concerning fertility. LIMITATIONS, REASONS FOR CAUTION: There is possible selection bias, as clinicians who are more knowledgeable about PCOS may have been more likely to participate. Clinicians' views may also differ in other countries. WIDER IMPLICATIONS OF THE FINDINGS: These findings underscore the vital need to first consider PCOS a diagnosis of exclusion and use caution before giving a diagnosis in order to reduce misdiagnosis, as suggested by clinicians in our study. Until there is greater standardisation of diagnostic criteria, more transparent conversations with women may help them understand the uncertainties surrounding the criteria and limitations in the evidence. Additionally, clinicians emphasised the importance of education and reassurance to minimise the potential harmful impact of the diagnosis and improve patient-centred outcomes. STUDY FUNDING/COMPETING INTEREST(S): The study was funded by the University of Sydney Lifespan Research Network and an NHMRC Program Grant (APP1113532). T.C. is supported by an Australian Government Research Training Program (RTP) Scholarship and a Sydney Medical School Foundation Scholarship, from the The University of Sydney, Australia. B.W.M. reports consultancy for ObsEva, Merck, Merck KGaA and Guerbet. No further competing interests exist. TRIAL REGISTRATION NUMBER: N/A.

The benefits and harms of receiving a polycystic ovary syndrome diagnosis: a qualitative study of women's experiences.

STUDY QUESTION: What are the benefits and harms of receiving a polycystic ovary syndrome (PCOS) diagnosis in a community sample of women, including impact on psychosocial wellbeing, lifestyle choices and behaviour? SUMMARY ANSWER: Although some women benefit considerably from the diagnosis, such as through increased awareness and reassurance, women with minimal symptoms may experience more harm than benefit, including long-lasting anxiety and altered life plans. WHAT IS KNOWN ALREADY: Disease labels can validate symptoms and play a vital role in understanding and coping with illness; however, they can also cause harm by evoking illness schemas about severity and permanence. Regarding PCOS, the diagnostic criteria have expanded over time to include women with milder phenotypes (such as those without signs of androgen excess). This has occurred despite limited investigation of the benefits and harms of the diagnosis and has increased the number of women diagnosed. STUDY DESIGN SIZE DURATION: Semi-structured interviews were conducted face-to-face or by telephone with 26 participants from April-July 2018 to explore women's experiences with the diagnosis, including the benefits and harms of receiving the diagnosis and the impact on their life. PARTICIPANTS/MATERIALS SETTING METHODS: In total, 26 women in the community self-reporting a diagnosis of PCOS (reporting mild to severe symptoms) made by a medical doctor, aged 18-45 years and living in Australia were recruited through social media. Data were analysed thematically using Framework analysis. MAIN RESULTS AND THE ROLE OF CHANCE: The study identified a range of both positive and negative effects of a PCOS diagnosis in the immediate, short and long-term, which were influenced by symptom severity, expectations and experience. For women with previously unexplained and bothersome symptoms, it was a relief to receive a diagnosis, and this resulted in an increased understanding about the importance of a healthy lifestyle. By contrast, women with milder symptoms often reported feeling shocked and overwhelmed by the diagnosis, consequently experiencing anxiety about the associated long-term risks. The majority of women, regardless of symptom severity, experienced prolonged worry and anxiety about infertility, resulting for some in risk taking with contraception, unintended pregnancies, pressure to conceive early or altered life plans. With time, many women developed positive coping strategies and perceived the diagnosis to be valuable, including those who felt they had experienced minimal benefit or even harm. LIMITATIONS REASONS FOR CAUTION: PCOS diagnosis was self-reported and the sample was highly educated. WIDER IMPLICATIONS OF THE FINDINGS: Fear of infertility was salient for many women, underscoring the need for accurate information, counselling and reassurance of fertility potential. Given the risk of significant consequences, health professionals should use a tailored approach to PCOS diagnosis to increase the benefits of appropriate and timely diagnosis for women affected by significant symptoms, while reducing the harms of unnecessarily labelling healthy women for whom the benefits of a diagnosis are small. STUDY FUNDING/COMPETING INTERESTS: The study was funded by the University of Sydney Lifespan Research Network and an NHMRC Program Grant (APP1113532). B.W.M. reports consultancy for ObsEva, Merck, Merck KGaA and Guerbet. No further competing interests exist. TRIAL REGISTRATION NUMBER: N/A.

Leukocyte Hsp72 mRNA transcription does not differ between males and females during heat acclimation.

Purpose: Thermotolerance is an acquired state of increased cytoprotection achieved following single or repeated exposures to heat stress, in part characterized by changes in the intracellular 72 kda heat shock protein (HSP72; HSPA1A). Females have demonstrated reduced exercise induced HSP72 in comparison to males. This study examined sex differences in heat shock protein 72 messenger ribonucleic acid (Hsp72 mRNA) transcription during heat acclimation (HA) to identify whether sex differences were a result of differential gene transcription. Methods: Ten participants (5M, 5F) performed 10, 90 min controlled hyperthermia [rectal temperature (Tre) ≥ 38.5°C] HA sessions over 12 d. Leukocyte Hsp72 mRNA was measured pre and post D1, D5, and D10, via Reverse transcription polymerase chain reaction (RT-QPCR). Results: HA was evidenced by a reduction in resting Tre (-0.4 ± 0.5°C) and resting heart rate [(HR); -13 ± 7 beats.min-1] following HA (p ≤ 0.05). During HA no difference (p > 0.05) was observed in ΔTre between males (D1 = 1.5 ± 0.2°C; D5 = 1.6 ± 0.4°C; D10 = 1.8 ± 0.3°C) and females (D1 = 1.5 ± 0.5°C; D5 = 1.4 ± 0.2°C; D10 = 1.8 ± 0.3°C). This was also true of mean Tre demonstrating equality of thermal stimuli for mRNA transcription and HA. There were no differences (p > 0.05) in Hsp72 mRNA expression between HA sessions or between males (D1 = +1.8 ± 1.5-fold; D5 = +2.0 ± 1.0 fold; D10 = +1.1 ± 0.4-fold) and females (D1 = +2.6 ± 1.8-fold; D5 = +1.8 ± 1.4-fold; D10 = +0.9 ± 1.9-fold). Conclusions: This experiment demonstrates that there is no difference in Hsp72 mRNA increases during HA between sexes when controlled hyperthermia HA is utilised. Gender specific differences in exercise-induced HSP72 reported elsewhere likely result from post-transcriptional events.

A comparison of males and females' temporal patterning to short- and long-term heat acclimation.

The current study assessed sex differences in thermoregulatory and physiological adaptation to short-term (STHA) and long-term heat acclimation (LTHA). Sixteen (eight males; eight females) participants performed three running heat tolerance tests (RHTT), preceding HA (RHTT1), following 5 days HA (RHTT2) and 10 days HA (RHTT3). The RHTT involved 30-min running (9 km/h, 2% gradient) in 40 °C, 40% relative humidity. Following STHA, resting rectal temperature (Trrest ) (males: -0.24 ± 0.16 °C, P ≤ 0.001; females: -0.02 ± 0.08 °C, P = 0.597), peak rectal temperature (Trpeak ) (males: -0.39 ± 0.36 °C, P ≤ 0.001; females -0.07 ± 0.18 °C, P = 0.504), and peak heart rate (males: -14 ± 12 beats/min, P ≤ 0.001; females: -5 ± 3 beats/min, P = 0.164) reduced in males, but not females. Following STHA, sweat rate relative to body surface area (SRBSA ) increased (428 ± 269 g/h/m(2) , P = 0.029) in females, but not males (-11 ± 286 g/h/m(2) , P = 0.029). Following LTHA, Trrest (males: -0.04 ± 0.15 °C, P = 0.459; females: -0.22 ± 0.12 °C, P ≤ 0.01) and Trpeak (males: -0.05 ± 0.26 °C, P = 0.590; females: -0.41 ± 0.24 °C, P ≤ 0.01) reduced in females, but not males. Following LTHA, SRBSA increased in males (308 ± 346 g/h/m(2) , P = 0.029), but not females (44 ± 373 g/h/m(2) , P = 0.733). Males and females responded to STHA; however, females required LTHA to establish thermoregulatory and cardiovascular stability. HA protocols should be designed to target sex differences in thermoregulation for optimal adaptation.

Cardiovascular risk scores do not account for the effect of treatment: a review.

OBJECTIVE: To compare the strengths and limitations of cardiovascular risk scores available for clinicians in assessing the global (absolute) risk of cardiovascular disease. DESIGN: Review of cardiovascular risk scores. DATA SOURCES: Medline (1966 to May 2009) using a mixture of MeSH terms and free text for the keywords 'cardiovascular', 'risk prediction' and 'cohort studies'. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: A study was eligible if it fulfilled the following criteria: (1) it was a cohort study of adults in the general population with no prior history of cardiovascular disease and not restricted by a disease condition; (2) the primary objective was the development of a cardiovascular risk score/equation that predicted an individual's absolute cardiovascular risk in 5-10 years; (3) the score could be used by a clinician to calculate the risk for an individual patient. RESULTS: 21 risk scores from 18 papers were identified from 3536 papers. Cohort size ranged from 4372 participants (SHS) to 1591209 records (QRISK2). More than half of the cardiovascular risk scores (11) were from studies with recruitment starting after 1980. Definitions and methods for measuring risk predictors and outcomes varied widely between scores. Fourteen cardiovascular risk scores reported data on prior treatment, but this was mainly limited to antihypertensive treatment. Only two studies reported prior use of lipid-lowering agents. None reported on prior use of platelet inhibitors or data on treatment drop-ins. CONCLUSIONS: The use of risk-factor-modifying drugs-for example, statins-and disease-modifying medication-for example, platelet inhibitors-was not accounted for. In addition, none of the risk scores addressed the effect of treatment drop-ins-that is, treatment started during the study period. Ideally, a risk score should be derived from a population free from treatment. The lack of accounting for treatment effect and the wide variation in study characteristics, predictors and outcomes causes difficulties in the use of cardiovascular risk scores for clinical treatment decision.

Systematic review and individual patient data meta-analysis of diagnosis of heart failure, with modelling of implications of different diagnostic strategies in primary care.

OBJECTIVES: To assess the accuracy in diagnosing heart failure of clinical features and potential primary care investigations, and to perform a decision analysis to test the impact of plausible diagnostic strategies on costs and diagnostic yield in the UK health-care setting. DATA SOURCES: MEDLINE and CINAHL were searched from inception to 7 July 2006. 'Grey literature' databases and conference proceedings were searched and authors of relevant studies contacted for data that could not be extracted from the published papers. REVIEW METHODS: A systematic review of the clinical evidence was carried out according to standard methods. Individual patient data (IPD) analysis was performed on nine studies, and a logistic regression model to predict heart failure was developed on one of the data sets and validated on the other data sets. Cost-effectiveness modelling was based on a decision tree that compared different plausible investigation strategies. RESULTS: Dyspnoea was the only symptom or sign with high sensitivity (89%), but it had poor specificity (51%). Clinical features with relatively high specificity included history of myocardial infarction (89%), orthopnoea (89%), oedema (72%), elevated jugular venous pressure (70%), cardiomegaly (85%), added heart sounds (99%), lung crepitations (81%) and hepatomegaly (97%). However, the sensitivity of these features was low, ranging from 11% (added heart sounds) to 53% (oedema). Electrocardiography (ECG), B-type natriuretic peptides (BNP) and N-terminal pro-B-type natriuretic peptides (NT-proBNP) all had high sensitivities (89%, 93% and 93% respectively). Chest X-ray was moderately specific (76-83%) but insensitive (67-68%). BNP was more accurate than ECG, with a relative diagnostic odds ratio of ECG/BNP of 0.32 (95% CI 0.12-0.87). There was no difference between the diagnostic accuracy of BNP and NT-proBNP. A model based upon simple clinical features and BNP derived from one data set was found to have good validity when applied to other data sets. A model substituting ECG for BNP was less predictive. From this a simple clinical rule was developed: in a patient presenting with symptoms such as breathlessness in whom heart failure is suspected, refer directly to echocardiography if the patient has a history of myocardial infarction or basal crepitations or is a male with ankle oedema; otherwise, carry out a BNP test and refer for echocardiography depending on the results of the test. On the basis of the cost-effectiveness analysis carried out, such a decision rule is likely to be considered cost-effective to the NHS in terms of cost per additional case detected. The cost-effectiveness analysis further suggested that, if likely benefit to the patient in terms of improved life expectancy is taken into account, the optimum strategy would be to refer all patients with symptoms suggestive of heart failure directly for echocardiography. CONCLUSIONS: The analysis suggests the need for important changes to the NICE recommendations. First, BNP (or NT-proBNP) should be recommended over ECG and, second, some patients should be referred straight for echocardiography without undergoing any preliminary investigation. Future work should include evaluation of the clinical rule described above in clinical practice.

Antibiotics for bronchiolitis in children.

BACKGROUND: Bronchiolitis is a serious, potentially life-threatening respiratory illness commonly affecting young babies. It is most often caused by Respiratory Syncytial Virus (RSV). The diagnosis is usually made on clinical grounds (especially tachypnoea and wheezing in a child less than two years of age). Antibiotics are not recommended for bronchiolitis unless there is concern about complications such as secondary bacterial pneumonia. Despite this, they are used at rates of 34 to 99% in uncomplicated cases. OBJECTIVES: To evaluate the use of antibiotics for bronchiolitis. SEARCH STRATEGY: We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL) which includes the Acute Respiratory Infection Groups' specialised register, the Database of Abstracts of Reviews of Effects (DARE) (The Cochrane Library Issue 3, 2006); MEDLINE (January 1966 to August Week 2, 2006); EMBASE (1990 to March 2006); and Current Contents (2001 to September 2006). SELECTION CRITERIA: Types of studies: single or double blind randomised controlled trials comparing antibiotics to placebo in the treatment of bronchiolitis. TYPES OF PARTICIPANTS: children under the age of two years diagnosed with bronchiolitis using clinical criteria (including respiratory distress preceded by coryzal symptoms with or without fever). Types of interventions: oral, intravenous, intramuscular or inhaled antibiotics versus placebo. Types of outcome measures: primary clinical outcomes: time for the resolution of symptoms/signs (pulmonary markers: respiratory distress; wheeze; crepitations; oxygen saturation; and fever). SECONDARY OUTCOMES: hospital admissions; time to discharge from hospital; re-admissions; complications/adverse events developed; and radiological findings. DATA COLLECTION AND ANALYSIS: All data were analysed using Review Manager software, version 4.2.7. MAIN RESULTS: One study met our inclusion criteria. It randomised children presenting clinically with bronchiolitis to either ampicillin or placebo. The main outcome measure was duration of illness and death. There was no significant difference between the two groups for length of illness and there were no deaths in either group. AUTHORS' CONCLUSIONS: This review found no evidence to support the use of antibiotics for bronchiolitis. This results needs to be treated with caution given only one RCT justified inclusion. It is unlikely that simple RCTs of antibiotics against placebo for bronchiolitis will be undertaken in future. Research to identify a possible small subgroup of patients presenting with bronchiolitis-like symptoms who may benefit from antibiotics may be justified. Otherwise, research may be better focussed on determining the reasons for clinicians to use antibiotics so readily for bronchiolitis, and ways of reducing their anxiety, and therefore their use of antibiotics for bronchiolitis.

Muscle metabolism during constant- and alternating-intensity exercise around critical power.

Few studies have focused on the metabolic responses to alternating high- and low-intensity exercise and, specifically, compared these responses to those seen during constant-load exercise performed at the same average power output. This study compared muscle metabolic responses between two patterns of exercise during which the intensity was either constant and just below critical power (CP) or that oscillated above and below CP. Six trained males (mean +/- SD age 23.6 +/- 2.6 y) completed two 30-minute bouts of cycling (alternating and constant) at an average intensity equal to 90 % of CP. The intensity during alternating exercise varied between 158 % CP and 73 % CP. Biopsy samples from the vastus lateralis muscle were taken before (PRE), at the midpoint and end (POST) of exercise and analysed for glycogen, lactate, PCr and pH. Although these metabolic variables in muscle changed significantly during both patterns of exercise, there were no significant differences (p > 0.05) between constant and alternating exercise for glycogen (PRE: 418.8 +/- 85 vs. 444.3 +/- 70; POST: 220.5 +/- 59 vs. 259.5 +/- 126 mmol x kg (-1) dw), lactate (PRE: 8.5 +/- 7.7 vs. 8.5 +/- 8.3; POST: 49.9 +/- 19.0 vs. 42.6 +/- 26.6 mmol x kg (-1) dw), phosphocreatine (PRE: 77.9 +/- 11.6 vs. 75.7 +/- 16.9; POST: 65.8 +/- 12.1 vs. 61.2 +/- 12.7 mmol x kg (-1) dw) or pH (PRE: 6.99 +/- 0.12 vs. 6.99 +/- 0.08; POST: 6.86 +/- 0.13 vs. 6.85 +/- 0.06), respectively. There were also no significant differences in blood lactate responses to the two patterns of exercise. These data suggest that, when the average power output is similar, large variations in exercise intensity exert no significant effect on muscle metabolism.

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.

Oxygen uptake kinetics during supra VO2max treadmill running in humans.

Accurate classification of VO2 kinetics is essential to correctly interpret its control mechanisms. The purpose of this study was to examine VO2 kinetics in severe and supra-maximal intensity running exercise using two modelling techniques. Nine subjects (mean +/- S.D: age, 27 +/- 7 years; mass, 69.8 +/- 9.0 kg; VO2max, 59.1 +/- 1.8 mL x kg x min(-1)) performed a series of "square-wave" exercise transitions to exhaustion at running speeds equivalent to 80% of the difference between the VO2 at LT and VO2max (delta), and at 100%, 110% and 120% VO2max. The VO2 response was modelled with an exponential model and with a semi-logarithmic transformation, the latter assuming a certain steady state VO2. With the exponential model there was a significant reduction in the "gain" of the primary component in supra-maximal exercise (167 +/- 5 mL x kg(-1) x km(-1) at 80% delta to 142 +/- 5 mL x kg(-1) x km(-1) at 120% VO2max, p = 0.005). The time constant of the primary component also reduced significantly with increasing intensity (17.8 +/- 1.1 s at 80% delta to 12.5 +/- 1.2 s at 120% VO2max, p < 0.05). However, in contrast, using the semi-log model, the time constant significantly increased with intensity (30.9 +/- 13.5 s at 80% delta to 72.2 +/- 23.9 s at 120% VO2max, p < 0.05). Not withstanding the need for careful interpretation of mathematically modelled data, these results demonstrate that neither the gain nor the time constant of the VO2 primary component during treadmill running are invariant across the severe and supra-maximal exercise intensity domains when fit with an exponential model. This suggests the need for a reappraisal of the VO2/work rate relationship in running exercise.

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.

Terlipressin for acute esophageal variceal hemorrhage.

BACKGROUND: Terlipressin (triglycyl lysine vasopressin) is a synthetic analogue of vasopressin, which has been used in the treatment of acute variceal hemorrhage. In contrast to vasopressin, terlipressin can be administered as intermittent injections instead of continuous intravenous infusion and it has a safer adverse reactions profile. However, its effectiveness remains uncertain. OBJECTIVES: To determine if treatment with terlipressin improves outcome in acute esophageal variceal hemorrhage and is safe. SEARCH STRATEGY: Randomized clinical trials were identified by searching the following databases (November 1999): The Cochrane Hepato-Biliary Group Controlled Trials Register, The Cochrane Controlled Trials Register on The Cochrane Library (Issue 3, 1999), MEDLINE, EMBASE, Biosis, and Current Contents. The bibliographies of identified publications were checked. Experts in the field and the manufacturers of terlipressin were contacted. For the update of this review, no new randomized clinical trials were identified on any of the databases (October 2002). SELECTION CRITERIA: All randomized clinical trials, which compared terlipressin with: (a) placebo or no treatment, (b) balloon tamponade, (c) endoscopic treatment, (d) octreotide, (e) somatostatin and (f) vasopressin, in the setting of acute variceal hemorrhage. DATA COLLECTION AND ANALYSIS: Eligibility, trial quality assessment and data extraction were done independently by two reviewers. The primary outcome measure was mortality. Secondary outcomes were failure of initial hemostasis, rebleeding, procedures required for uncontrolled bleeding or rebleeding, transfusion requirements and length of hospitalization. MAIN RESULTS: Twenty studies were identified for all the comparison groups, involving 1609 patients. There were seven studies (with 443 patients) comparing terlipressin to placebo, five of which were considered to be high quality studies based on the Jadad scale. The meta-analysis indicates that terlipressin was associated with a statistically significant reduction in all cause mortality compared to placebo (relative risk 0.66, 95% confidence interval 0.49 to 0.88). Three studies (with 302 patients) were identified comparing terlipressin to somatostatin, two of which were high quality studies; only one high quality study (219 patients) comparing terlipressin to endoscopic treatment was identified. Within the limited power provided by these small numbers of patients, no statistically significant difference was demonstrated between terlipressin and either somatostatin or endoscopic treatment in any of the outcomes. For the remaining comparison groups (terlipressin versus balloon tamponade, terlipressin versus octreotide, and terlipressin versus vasopressin) only small, low quality studies were identified and no difference was demonstrated in any of the major outcomes. There was no significant difference between the terlipressin group and any of the comparison groups in the number of adverse events that caused death or withdrawal of medication. REVIEWER'S CONCLUSIONS: On the basis of a 34% relative risk reduction in mortality, terlipressin should be considered to be effective in the treatment of acute variceal hemorrhage. Further, since no other vasoactive agent has been shown to reduce mortality in single studies or meta-analyses, terlipressin might be the vasoactive agent of choice in acute variceal bleeding.

Promoting better use of the PSA test in general practice: randomized controlled trial of educational strategies based on outreach visits and mailout.

BACKGROUND: Prostate-specific antigen (PSA) testing for prostate cancer is controversial. Demand for PSA testing is likely to rise in the UK, Australia and other western countries. Primary care needs to develop appropriate strategies to respond to this demand. OBJECTIVES: Our aim was to compare the effectiveness of educational outreach visits (EOVs) and mailout strategies targeting PSA testing in Australian primary care. METHODS: A randomized controlled trial was conducted in general practices in southern Adelaide. The main outcome measures at baseline, 6 months and 12 months post-intervention were PSA testing rates and GP knowledge in key areas relating to prostate cancer and PSA testing. RESULTS: The interventions were able to demonstrate a change in clinical practice. In the 6 months post-intervention, median PSA testing rate in the EOV group was significantly lower than in the postal group, which in turn was significantly lower than the control group (P < 0.001). Statistically significant differences were not, however, maintained in the 6-12 month post-intervention period. The EOV group, at 6 months follow-up, had a significantly greater proportion of "correct" responses than the control group to questions about prostate cancer treatment effectiveness (P = 0.004) and endorsement of PSA screening by professional bodies (P = 0.041). CONCLUSIONS: Primary care has a central role in PSA testing for prostate cancer. Clinical practice in this area is receptive to evidence-based interventions.

Systematic review: terlipressin in acute oesophageal variceal haemorrhage.

BACKGROUND: Controversy exists surrounding pharmacological therapy in acute variceal bleeding. AIM: To determine the efficacy and safety of terlipressin. METHODS: Randomized trials were identified and duplicate, independent, review identified 20 randomized trials involving 1609 patients that compared terlipressin with placebo, balloon tamponade, endoscopic treatment, octreotide, somatostatin or vasopressin for treatment of acute oesophageal variceal haemorrhage. RESULTS: Meta-analysis showed that compared to placebo, terlipressin reduced mortality (relative risk 0.66, 95% CI 0.49-0.88), failure of haemostasis (relative risk 0.63, 95% CI 0.45-0.89) and the number of emergency procedures per patient required for uncontrolled bleeding or rebleeding (relative risk 0.72, 95% CI 0.55-0.93). When used as an adjuvant to endoscopic sclerotherapy, terlipressin reduced failure of haemostasis (relative risk 0.75, 95% CI 0.58-0.96), and had an effect on reducing mortality that approached statistical significance (relative risk 0.74, 95% CI 0.53-1.04). No significant difference was demonstrated between terlipressin and endoscopic sclerotherapy, balloon tamponade, somatostatin or vasopressin. Haemostasis was achieved more frequently with octreotide compared to terlipressin (relative risk 1.62, 95% CI 1.05-2.50), but this result was based on unblinded studies. Adverse events were similar between terlipressin and the other comparison groups except for vasopressin, which caused more withdrawals due to adverse events. CONCLUSIONS: Terlipressin is a safe and effective treatment for acute oesophageal variceal bleeding, with or without adjuvant endoscopic sclerotherapy. Terlipressin appears to reduce mortality in acute oesophageal variceal bleeding compared to placebo, and is the only pharmacological agent shown to do so. Future studies will be required to detect potential mortality differences between terlipressin and other therapeutic approaches.

Physiological responses during exercise to exhaustion at critical power.

Critical power (CP) is a theoretical construct derived from a series of constant load tests to failure. Many studies have examined the methodological limitations of deriving CP, but few studies have examined the responses to exercise at CP in well-trained individuals. The purpose of the present study was to examine the physiological responses to exercise at CP. Seven male subjects [mean (SD) body mass 75.6 (6.4) kg, maximum oxygen uptake 4.6 (0.7) l min(-1)] performed three constant load tests to derive CP. Subjects then exercised at CP until volitional exhaustion. Heart rate, oxygen consumption and blood lactate concentration were measured throughout. Repeated measures analysis of variance revealed significant differences over time in heart rate 118 (24) to 177(5) beats min(-1), oxygen consumption 3.7 (0.6) to 4.1 (0.5) l min(-1)and blood lactate concentration 4.3 (1.8) to 6.5 (2.0) mM. All seven subjects completed 20 min of exercise with the range of time to failure at CP from 20 min 1 s to 40 min 37 s. Time to failure and maximum oxygen consumption were significantly correlated (r = 0.779, P < 0.05). We conclude, therefore, that CP does not represent a sustainable steady-state intensity of exercise.