The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies

Adherence to biologic DMARD therapies in rheumatoid arthritis

IMPORTANCE OF THE FIELD

The efficacy of the biologic disease-modifying antirheumatic drugs (DMARDs) shown in clinical trials may be jeopardized due to prevalent poor patient adherence.

AREAS COVERED IN THIS REVIEW

Patient adherence including compliance and persistence with biologic DMARDs in rheumatoid arthritis.

WHAT THE READER WILL GAIN

This is a comprehensive review of the literature. The various definitions and methodologies of measurement used in adherence research are reviewed and data are presented by separating compliance and persistence. Differences in compliance rates were mainly based on numerical trends. There was evidence for and against greater persistence with infliximab versus adalimumab and etanercept. There was a trend in favour of greater compliance and lower persistence with TNF-alpha inhibitor monotherapy versus in combination therapy with methotrexate.

TAKE HOME MESSAGE

The evidence suggests that adherence to biologic DMARDs is suboptimal. When further research is applied in the field, agreed definitions and methodology need to be used to allow for cross-study comparisons. In addition, adherence should be assessed in conjunction with clinical outcomes and not on its own so that it can be better understood what levels of adherence provide the required clinical outcomes.

Prediction of malignant middle cerebral artery infarction by magnetic resonance imaging within 6 hours of symptom onset: A prospective multicenter observational study

OBJECTIVE

Early identification of patients at risk of space-occupying "malignant" middle cerebral artery (MCA) infarction (MMI) is needed to enable timely decision for potentially life-saving treatment such as decompressive hemicraniectomy. We tested the hypothesis that acute stroke magnetic resonance imaging (MRI) predicts MMI within 6 hours of stroke onset.

METHODS

In a prospective, multicenter, observational cohort study patients with acute ischemic stroke and MCA main stem occlusion were studied by MRI including diffusion-weighted imaging (DWI), perfusion imaging (PI), and MR-angiography within 6 hours of symptom onset. Multivariate regression analysis was used to identify clinical and imaging predictors of MMI.

RESULTS

Of 140 patients included, 27 (19.3%) developed MMI. The following parameters were identified as independent predictors of MMI: larger acute DWI lesion volume (per 1 ml odds ratio [OR] 1.04, 95% confidence interval [CI] 1.02-1.06; p < 0.001), combined MCA + internal carotid artery occlusion (5.38, 1.55-18.68; p = 0.008), and severity of neurological deficit on admission assessed by the National Institutes of Health Stroke Scale score (per 1 point 1.16, 1.00-1.35; p = 0.053). The prespecified threshold of a DWI lesion volume >82 ml predicted MMI with high specificity (0.98, 95% CI 0.94-1.00), negative predictive value (0.90, 0.83-0.94), and positive predictive value (0.88, 0.62-0.98), but sensitivity was low (0.52, 0.32-0.71).

INTERPRETATION

Stroke MRI on admission predicts malignant course in severe MCA stroke with high positive and negative predictive value and may help in guiding treatment decisions, such as decompressive surgery. In a subset of patients with small initial DWI lesion volumes, repeated diagnostic tests are required.

Sociodemographic factors and vestibular schwannoma: a Danish nationwide cohort study

Vestibular schwannoma (VS) (or acoustic neuroma) accounts for about 5%-6% of all intracranial tumors; little is known about the etiology. We investigated the association between various sociodemographic indicators and VS in a cohort of 3.26 million Danish residents, with 1087 cases identified in 35 308 974 person-years under risk, with data accrued from 1993 to 2006. Complete ascertainment of cases was ensured by using population-based and clinical cancer registries. Information on sociodemographic indicators was obtained on an annually updated individual level from Statistics Denmark. Log-linear Poisson regression models were used to estimate incidence rate ratios (IRRs). Linear regression models were used to examine the association between sociodemographic indicators and tumor size. We found that IRRs decreased gradually with decreasing level of education, with values of 0.62 (95% CI: 0.49-0.78) for men and 0.62 (95% CI: 0.50-0.77) for women with a basic education compared with a higher education. Similar results were found for disposable income. Marital status was associated with a higher incidence of VS in men but not women; nonmarried men with a basic education had an IRR of 0.34 (95% CI: 0.23-0.50) compared with married men with a higher education. Lower incidence rates were also observed among unemployed or early-retirement pensioners, whereas there were no differences in incidence rates across the broad groups of occupations and across the types of districts. Sociodemographic indicators were not associated with the tumor size. The magnitude of the differences in incidence rates across the groups of different socioeconomic indicators suggests a high potential for earlier diagnosis of VS by improving the awareness of early symptoms.

The role of colonoscopy in the management of intestinal obstruction: a 20-year retrospective study

PURPOSE

The aim of the study was to assess the use colonoscopy over time in the assessment of large bowel obstruction in a tertiary university hospital.

METHODS

Retrospective analysis of surgical and colonoscopy records for the years 1990-2009 in a university hospital. All patients diagnosed with non-conservatively managed bowel obstruction were included.

RESULTS

We recorded 644 patients diagnosed with non-conservatively managed bowel obstruction. Four hundred forty-one (67.3%) were managed only by surgery, 157 (23.6%) were managed by colonoscopy, and 46 (6.9%) by combined colonoscopy and surgery. Patients over 77 years were more likely to receive colonoscopy as monotherapy or combined with surgery as compared to younger patients. Management by colonoscopy only and by combined colonoscopy and surgery increased over time.

CONCLUSIONS

Colonoscopy in the management of non-conservatively treated bowel obstruction increased over time. However, therapeutic colonoscopy still has a limited role in bowel obstruction either as monotherapy or combined with surgery.

The genetic and environmental contribution to the occurrence of bladder pain syndrome: an empirical approach in a nationwide population sample

BACKGROUND

The aetiology of bladder pain syndrome (BPS) remains poorly understood, and a number of pathogenic mechanisms have been proposed. The importance of genetic factors for BPS is receiving growing attention, but data so far are of a preliminary nature.

OBJECTIVE

To empirically assess the genetic and environmental contribution to BPS in a population-based sample of twins.

DESIGN, SETTING, AND PARTICIPANTS

The study included >25,000 twins born between 1959 and 1985. Individuals with BPS were identified using latent class cluster analysis (LCCA) based on self-reported symptoms from a nationwide screening for complex diseases in the Swedish Twin Registry. By comparing monozygotic and dizygotic twins, we estimated twin similarity and the relative proportions of phenotypic variance resulting from genetic and environmental factors.

MEASUREMENTS

Twin similarity was measured.

RESULTS AND LIMITATIONS

The LCCA yielded an overall BPS prevalence of 1.1% and 2.4% for males and females, respectively. In males, the contribution of genetic effects to BPS could not be assessed because of the small number of concordant twin pairs. In women, twin similarity estimates indicated a genetic component for the aetiology of BPS, but genetic factors contributed less than one-third of the total variation in susceptibility to BPS. Nonshared environmental factors accounted for more than two-thirds of the variance, whereas early nongenetic factors shared within the family were of little or no consequence to the risk of developing BPS later in life. Use of self-reported symptoms to define the disease phenotype is a limitation of the study.

CONCLUSIONS

The influence of environmental factors in the development of BPS in women is substantial, whereas genetic influences are of only modest importance for the possibility of developing the disease.

Insulin resistance is related to impaired lung function in morbidly obese women: a case-control study

BACKGROUND

There is growing evidence suggesting an association between type 2 diabetes and impaired pulmonary function. However, the role of insulin resistance itself remains to be elucidated. The aim of the study is to determine whether obese patients with insulin resistance without diabetes have reduced pulmonary function in comparison with non-diabetic obese subjects without insulin resistance.

METHODS

Seventy-five morbidly obese non-diabetic women [50 with an insulin resistance index (homeostasis model assessment, HOMA-IR) ≥ 3.8-cases-and 25 with HOMA-IR < 3.8-controls-] with a history of not smoking and without prior cardiovascular or respiratory disease were prospectively recruited in the outpatient Obesity Unit of a university hospital. Both groups were closely matched by age, body mass index and waist circumference. Pulmonary function test included a forced spirometry and static pulmonary volume measurements.

RESULTS

Patients with HOMA-IR ≥ 3.8 showed lower forced expiratory volume at 1 s [mean difference - 7.6% of predicted (95% confidence interval - 14.2 to - 0.9); p = 0.025], and also a lower maximum midexpiratory flow [mean difference - 16.4% of predicted (95% confidence interval - 30.9 to - 2.0); p = 0.026] in comparison with those with HOMA-IR < 3.8. Significant negative correlations between HOMA-IR and forced expiratory volume at 1 s, maximum midexpiratory flow and forced vital capacity were detected. Multiple linear regression analysis showed that HOMA-IR (β = - 0.323, p = 0.002) and total lung capacity (β = 0.468, p < 0.001) were independently associated with forced expiratory volume at 1 s (r(2) = 0.358).

CONCLUSIONS

Insulin resistance is related to respiratory function impairment in morbidly obese women. Our results strongly suggest that the metabolic pathways related to insulin resistance are crucial in initiating lung abnormalities previously described in type 2 diabetic patients. Copyright © 2010 John Wiley & Sons, Ltd.

Genetic studies of IgA nephropathy: past, present, and future

Immunoglobulin A nephropathy (IgAN) is the most common form of primary glomerulonephritis worldwide and an important cause of kidney disease in young adults. Highly variable clinical presentation and outcome of IgAN suggest that this diagnosis may encompass multiple subsets of disease that are not distinguishable by currently available clinical tools. Marked differences in disease prevalence between individuals of European, Asian, and African ancestry suggest the existence of susceptibility genes that are present at variable frequencies in these populations. Familial forms of IgAN have also been reported throughout the world but are probably underrecognized because associated urinary abnormalities are often intermittent in affected family members. Of the many pathogenic mechanisms reported, defects in IgA1 glycosylation that lead to formation of immune complexes have been consistently demonstrated. Recent data indicates that these IgA1 glycosylation defects are inherited and constitute a heritable risk factor for IgAN. Because of the complex genetic architecture of IgAN, the efforts to map disease susceptibility genes have been difficult, and no causative mutations have yet been identified. Linkage-based approaches have been hindered by disease heterogeneity and lack of a reliable noninvasive diagnostic test for screening family members at risk of IgAN. Many candidate-gene association studies have been published, but most suffer from small sample size and methodological problems, and none of the results have been convincingly validated. New genomic approaches, including genome-wide association studies currently under way, offer promising tools for elucidating the genetic basis of IgAN.

Categorisation of continuous risk factors in epidemiological publications: a survey of current practice

Background

Reports of observational epidemiological studies often categorise (group) continuous risk factor (exposure) variables. However, there has been little systematic assessment of how categorisation is practiced or reported in the literature and no extended guidelines for the practice have been identified. Thus, we assessed the nature of such practice in the epidemiological literature. Two months (December 2007 and January 2008) of five epidemiological and five general medical journals were reviewed. All articles that examined the relationship between continuous risk factors and health outcomes were surveyed using a standard proforma, with the focus on the primary risk factor. Using the survey results we provide illustrative examples and, combined with ideas from the broader literature and from experience, we offer guidelines for good practice.

Results

Of the 254 articles reviewed, 58 were included in our survey. Categorisation occurred in 50 (86%) of them. Of those, 42% also analysed the variable continuously and 24% considered alternative groupings. Most (78%) used 3 to 5 groups. No articles relied solely on dichotomisation, although it did feature prominently in 3 articles. The choice of group boundaries varied: 34% used quantiles, 18% equally spaced categories, 12% external criteria, 34% other approaches and 2% did not describe the approach used. Categorical risk estimates were most commonly (66%) presented as pairwise comparisons to a reference group, usually the highest or lowest (79%). Reporting of categorical analysis was mostly in tables; only 20% in figures.

Conclusions

Categorical analyses of continuous risk factors are common. Accordingly, we provide recommendations for good practice. Key issues include pre-defining appropriate choice of groupings and analysis strategies, clear presentation of grouped findings in tables and figures, and drawing valid conclusions from categorical analyses, avoiding injudicious use of multiple alternative analyses.

Attitudes toward safety and teamwork in a maternity unit with embedded team training

The objective of this study was to identify any residual challenges in a unit with a track record of good clinical performance. A cross-sectional survey of frontline caregiver attitudes was conducted using a validated psychometric instrument. A total of 69% (91 of 132) of eligible participants completed questionnaires. The results indicated positive safety culture, teamwork climate, and job satisfaction. Perceptions of high workload and insufficient staffing levels were the most prominent negative observations but not to the detriment of job satisfaction or perception of work conditions. Male staff had consistently better safety attitudes in multivariate analyses. The authors identified 24-hour consultant (attending) presence and better support by management as prerequisites for further improvement. Teamwork and safety attitudes are positive in a unit with established interprofessional team training. Establishing better support by senior clinical and management leaders was identified as a necessary intervention to improve attitudes and safety.

Critical care trial design and interpretation: a primer

OBJECTIVE

Better understanding of the pathophysiology of critical illness has led to an increase in clinical trials designed to improve the clinical care and outcomes of patients with life-threatening illness. Knowledge of basic principles of clinical trial design and interpretation will assist the clinician in better applying the results of these studies into clinical practice.

DATA SOURCES

We review selected clinical trials to highlight important design features that will improve understanding of the results of critical care clinical trials designed to improve clinical care of the critically ill.

RESULTS

Trial design features such as patient selection, bias, sample size calculation, selection of subjects and controls, and primary outcome measure may influence the results of a critical care clinical trial designed to test a therapy targeting improved clinical care. In conjunction with trial design knowledge, understanding the size of the anticipated treatment effect, the importance of any clinical end point achieved, and whether patients in the trial are representative of typical patients with the illness will assist the reader in determining whether the results should be applied to specific patients or usual clinical practice.

CONCLUSIONS

Better understanding of important aspects of trial design and interpretation, such as whether patients enrolled in both intervention arms were comparable and whether the primary outcome of the trial is clinically important, will assist the bedside clinician in determining whether to apply the findings from the clinical study into clinical practice.

What are the causes of pre-existing dementia in patients with intracerebral haemorrhages?

In intracerebral haemorrhage, the most frequent underlying vasculopathies are cerebral amyloid angiopathy and hypertensive vasculopathy. Although both are associated with cognitive impairment, no study has focused on pre-existing dementia in patients with intracerebral haemorrhage. Therefore, we aimed to determine prevalence and mechanisms of pre-existing dementia in a large cohort of patients with an intracerebral haemorrhage. In a cohort of 417 patients, we evaluated the cognitive status before intracerebral haemorrhage with the Informant Questionnaire on Cognitive Decline in the Elderly. The cut-off to diagnose cognitive impairment with no dementia was 53 and 64 for pre-existing dementia. We determined factors associated with pre-existing dementia in multivariate analyses in the overall cohort and among patients with lobar only or deep only intracerebral haemorrhages. We performed post-mortem examinations when possible. Of 417 patients (median age 72 years, interquartile range 58-79), 58 (14%; 95% CI 11-18%) patients had cognitive impairment with no dementia and 65 had pre-existing dementia (16%; 95% CI 12-19%). In lobar intracerebral haemorrhage, the prevalence was 23%, and factors associated with pre-existing dementia were increasing age (odds ratio: 1.09 per year; 95% CI 1.02-1.15), having <8 years of education (odds ratio: 8.37; 95% CI 1.91-36.65) and increasing cortical atrophy (odds ratio: 3.34 per step; 95% CI 1.40-7.96). The five autopsied patients had Alzheimer's disease with cerebral amyloid angiopathy. In deep intracerebral haemorrhage, factors associated with pre-existing dementia were presence of old territorial vascular lesions (odds ratio: 4.52; 95% CI 1.18-17.42) and increasing severity of leucoaraiosis (odds ratio: 4.11 per step; 95% CI 1.73-9.75); the autopsied patient had small-vessel disease without Alzheimer's disease. These findings support the fact that pre-existing dementia is frequent in patients with intracerebral haemorrhage and may be the consequence of two different mechanisms: neurodegeneration with Alzheimer's disease and cerebral amyloid angiopathy in lobar intracerebral haemorrhage versus vascular process in deep intracerebral haemorrhage. These findings may contribute to the improvement of prevention and management of patients with intracerebral haemorrhages.

Increased levels of CRP and MCP-1 are associated with previously unknown abnormal glucose regulation in patients with acute STEMI: a cohort study

BACKGROUND

Inflammation plays an important role in the pathophysiology of both atherosclerosis and type 2 diabetes and some inflammatory markers may also predict the risk of developing type 2 diabetes. The aims of the present study were to assess a potential association between circulating levels of inflammatory markers and hyperglycaemia measured during an acute ST-elevation myocardial infarction (STEMI) in patients without known diabetes, and to determine whether circulating levels of inflammatory markers measured early after an acute STEMI, were associated with the presence of abnormal glucose regulation classified by an oral glucose tolerance test (OGTT) at three-month follow-up in the same cohort.

METHODS

Inflammatory markers were measured in fasting blood samples from 201 stable patients at a median time of 16.5 hours after a primary percutaneous coronary intervention (PCI). Three months later the patients performed a standardised OGTT. The term abnormal glucose regulation was defined as the sum of the three pathological glucose categories classified according to the WHO criteria (patients with abnormal glucose regulation, n = 50).

RESULTS

No association was found between inflammatory markers and hyperglycaemia measured during the acute STEMI. However, the levels of C-reactive protein (CRP) and monocyte chemoattractant protein-1 (MCP-1) measured in-hospital were higher in patients classified three months later as having abnormal compared to normal glucose regulation (p = 0.031 and p = 0.016, respectively). High levels of CRP (≥ 75 percentiles (33.13 mg/L)) and MCP-1 (≥ 25 percentiles (190 ug/mL)) were associated with abnormal glucose regulation with an adjusted OR of 3.2 (95% CI 1.5, 6.8) and 7.6 (95% CI 1.7, 34.2), respectively.

CONCLUSION

Elevated levels of CRP and MCP-1 measured in patients early after an acute STEMI were associated with abnormal glucose regulation classified by an OGTT at three-month follow-up. No significant associations were observed between inflammatory markers and hyperglycaemia measured during the acute STEMI.

Setting up, maintaining and evaluating an evidence based radiology journal club: the University of Michigan experience

The authors outline the steps involved in setting up, maintaining, and evaluating an evidence-based imaging journal club, using their collective experience at the University of Michigan. The article opens with a background to journal clubs in general and describes their changing purpose or role in recent decades. This should act as a useful framework or "how-to" guide to get things started. Different journal club formats are discussed, and the pros and cons of each are outlined. Suggestions for obtaining feedback from residents and for performing evaluation are also provided. In addition, useful information, references and links to useful resources are also given throughout the article. Finally, the authors share the positive (and negative) experiences of setting up, maintaining, and evaluating the University of Michigan's journal club, now in its third year. The authors welcome feedback from readers who have been involved in evidence-based imaging journal clubs to share their experiences, good and bad.

Genomic and metabolomic patterns segregate with responses to calcium and vitamin D supplementation

Inter-individual response differences to vitamin D and Ca supplementation may be under genetic control through vitamin D and oestrogen receptor genes, which may influence their absorption and/or metabolism. Metabolomic studies on blood and urine from subjects supplemented with Ca and vitamin D reveal different metabolic profiles that segregate with genotype. Genotyping was performed for oestrogen receptor 1 gene (ESR1) and vitamin D receptor gene (VDR) in fifty-six postmenopausal women. Thirty-six women were classified as low bone density as determined by a heel ultrasound scan and twenty women had normal bone density acting as ‘controls’. Those with low bone density (LBD) were supplemented with oral Ca and vitamin D and were classified according to whether they were ‘responders’ or ‘non-responders’ according to biochemical results before and after therapy compared to controls receiving no supplementation. Metabolomic studies on serum and urine were done for the three groups at 0 and 3 months of therapy using NMR spectroscopy with pattern recognition. The ‘non-responder’ group showed a higher frequency of polymorphisms in the ESR1 (codons 10 and 325) and VDR (Bsm1 and Taq1), compared with to the ‘responders’. The wild-type genotype for Fok1 was more frequent in those with LBD (70 %) compared with the control group (10 %). Distinctive patterns of metabolites were displayed by NMR studies at baseline and 3 months of post-treatment, segregating responders from non-responders and controls. Identification of potential ‘non-responders’ to vitamin D and Ca, before therapy, based on a genomic and/or metabolomic profile would allow targeted selection of optimal therapy on an individual basis.

The use and abuse of hypothesis tests: how to present P values

This overview highlights some of the key issues involved in performing and interpreting hypothesis tests. We describe the general approach taken in performing a hypothesis test with a focus on how to state the null and alternative hypothesis, and why two-sided tests are usually more appropriate than one-sided tests. We describe best practice techniques in performing and presenting the results of hypothesis tests. We recommend that, alongside any p-values, authors should also present estimates of the size of any treatment effects and their confidence intervals. Furthermore, they should specify the exact p-value rather than using terms such as 'NS' or the commonly used asterix notation. We discuss other pitfalls that are encountered at the analysis stage such as the use of repeated observations on individuals, the use of multiple tests on the data and the erroneous use of parametric tests when data are not normally distributed and vice versa. We highlight these points using two different examples: one looking at the use of compression stockings for preventing the occurrence of DVT on long-haul flights and a second hypothetical study comparing laser versus surgery techniques for the removal of varicose veins.

Systematic review of prospective studies investigating "remission" from amphetamine, cannabis, cocaine or opioid dependence

AIMS

To review and summarize existing prospective studies reporting on remission from dependence upon amphetamines, cannabis, cocaine or opioids.

METHODS

Systematic searches of the peer-reviewed literature were conducted to identify prospective studies reporting on remission from amphetamines, cannabis, cocaine or opioid dependence. Searches were limited to publication between 1990 and 2009. Reference lists of review articles and important studies were searched to identify additional studies. Remission was defined as no longer meeting diagnostic criteria for drug dependence or abstinence from drug use; follow-up periods of at least three years were investigated. The remission rate was estimated for each drug type, allowing pooling across studies with varying follow-up times.

RESULTS

There were few studies examining the course of psychostimulant dependence that met inclusion criteria (one for amphetamines and four for cocaine). There were ten studies of opioid and three for cannabis dependence. Definitions of remission varied and most did not clearly assess remission from dependence. Amphetamine dependence had the highest remission rate (0.4477; 95%CI 0.3991, 0.4945), followed by opioid (0.2235; 95%CI 0.2091, 0.2408) and cocaine dependence (0.1366; 95%CI 0.1244, 0.1498). Conservative estimates of remission rates followed the same pattern with cannabis dependence (0.1734; 95%CI 0.1430, 0.2078) followed by amphetamine (0.1637; 95%CI 0.1475, 0.1797), opioid (0.0917; 95%CI 0.0842, 0.0979) and cocaine dependence (0.0532; 95%CI 0.0502, 0.0597).

CONCLUSIONS

The limited prospective evidence suggests that "remission" from dependence may occur relatively frequently but rates may differ across drugs. There is very little research on remission from drug dependence; definitions used are often imprecise and inconsistent across studies and there remains considerable uncertainty about the longitudinal course of dependence upon these most commonly used illicit drugs.

Hormonal contraceptives for contraception in overweight or obese women

BACKGROUND

Obesity has reached epidemic proportions around the world. Metabolic changes in obesity and greater body mass may lead to reduced effectiveness of hormonal contraceptives, such as the skin patch, vaginal ring, implants, and injectables. We systematically reviewed the evidence on the effectiveness of hormonal contraceptives among overweight and obese women.

OBJECTIVES

To examine the effectiveness of hormonal contraceptives in preventing unplanned pregnancies among women who are overweight or obese versus women of lower weight or body mass index (BMI).

SEARCH STRATEGY

We searched MEDLINE, CENTRAL, POPLINE, EMBASE, ClinicalTrials.gov, and ICTRP. We also contacted investigators to identify other trials.

SELECTION CRITERIA

All study designs were eligible. Any type of hormonal contraceptive could have been examined. The primary outcome was pregnancy. Overweight or obese women must have been identified by an analysis cutoff for weight or BMI (kg/m(2)).

DATA COLLECTION AND ANALYSIS

Data were abstracted by two authors; life-table rates were included where available. For dichotomous variables, we computed an odds ratio with 95% confidence interval. The main comparisons were between overweight or obese women and women of lower weight or BMI.

MAIN RESULTS

We found 7 reports with data from 11 trials that included 39,531 women. One of three studies using BMI found a higher pregnancy risk for overweight or obese women. In the trial of two combination oral contraceptives, women with BMI >= 25 had greater pregnancy risk compared to those with BMI < 25 (OR 1.91; 95% CI 1.01 to 3.61). Among skin patch users, body weight was associated with pregnancy (reported P < 0.001) but BMI was not. Studies of a vaginal ring (never marketed) and a six-rod implant showed higher pregnancy rates for women weighing >= 70 kg versus those weighing < 70 kg (reported P values: 0.0013 and < 0.05, respectively). However, two implant studies showed no trend by body weight, and trials of an injectable had no pregnancies.

AUTHORS' CONCLUSIONS

Body weight addresses overall body size, while BMI generally reflects the amount of fat. Only one of three studies using BMI found a higher pregnancy risk for overweight women. The efficacy of implants and injectable contraceptives may be unaffected by body mass. The field could use trials of contraceptive methods with groups stratified by BMI. The current evidence on effectiveness by BMI is limited. However, the contraceptive methods examined here are still among the most effective when the recommended regimen is followed.

Meeting U.S. Healthy People 2010 levels of physical activity: agreement of 2 measures across 2 years

BACKGROUND

Measuring the way people vary across time in meeting recommended levels of physical activity should be a fundamental component of public health surveillance. However, we were unaware of prospective cohort studies that had examined this in a population base using convergent measures.

PURPOSE

We examined agreement between two validated measures used to estimate periodic change in the rate of meeting U.S. Healthy People 2010 guidelines for participation in moderate or vigorous physical activity.

METHODS

A cohort (N = 497) from a random, multiethnic sample of adults living in Hawaii was assessed every 6-months for 2 years starting spring 2004. Latent transition analysis classified people as meeting or not meeting the guidelines. Intra-class kappa statistics and multinomial logistic regression analysis were used to evaluate agreement.

RESULTS

Agreement for classifying stable classes of people who met or did not meet the guideline each time was substantial for vigorous activity (kappa approximately 0.65-0.70) but fair-to-moderate for moderate activity (kappa approximately 0.38-0.48). Agreement was poorer for classifying people who transitioned between meeting and not meeting the vigorous guideline (kappa approximately 0.45) or the moderate guideline (kappa approximately 0.21-0.29).

CONCLUSIONS

Rates of meeting the guidelines varied across time and were estimated differently by the two measures, especially for moderate activity. This finding illustrates an understudied problem for public health promotion. Accurate classification of change within people is necessary for determining exposure in outcome studies, personal determinants of sufficient activity, and for evaluating whether interventions are successful in sustaining increases in rates of meeting physical activity guidelines.

Long-term outcomes in pulmonary arterial hypertension in the first-line epoprostenol or first-line bosentan era

BACKGROUND

The aim of this study was to describe the long-term outcomes in idiopathic pulmonary arterial hypertension (IPAH) treated with first-line bosentan or intravenous (IV) epoprostenol, and additional therapy as needed.

METHODS

In a single-center, retrospective, longitudinal cohort, data on right heart catheterization, 6-minute walk distance (6MWD), disease progression and mortality were collected. Outcomes were assessed in first-line bosentan and first-line epoprostenol patients. To reduce selection bias due to differences between groups, two independent analyses were performed. First, a comparison was made of World Health Organization (WHO) Functional Class (FC) III patients. Second, to control for disease severity, a matched-pairs analysis was performed, with matching according to baseline cardiac output and exercise capacity and irrespective of FC at baseline.

RESULTS

Thirty-seven IPAH patients initiated first-line bosentan treatment and 37 first-line IV epoprostenol. Twenty-nine of the bosentan patients and 16 of the IV epoprostenol patients were in WHO FC III; demographic profiles were similar, although hemodynamic measurements and 6MWD suggested more severe disease in the IV epoprostenol group at treatment initiation. At 1 and 3 years, median change in 6MWD for patients initiating bosentan was +54 m (95% confidence interval: -3 to 76) and +71 m (-123 to 116), respectively, and +92 m (17 to 128) and +142 m (-6 to 242) for those on IV epoprostenol. Absence of disease progression of WHO FC III at 1 and 3 years was 72% and 45% with bosentan and 75% and 44% with IV epoprostenol, respectively. Survival at 1 and 3 years was 93% and 89% with bosentan and 94% and 75% with IV epoprostenol, respectively. Results were confirmed in matched-pairs analysis of 16 bosentan and 16 IV epoprostenol patients with similar disease severity.

CONCLUSIONS

First-line epoprostenol treatment may lead to greater improvement in exercise capacity than first-line bosentan. However, these greater exercise improvements did not translate into longer time to disease progression or survival.

Statins in the management of patients with aneurysmal subarachnoid hemorrhage: a systematic review and meta-analysis

BACKGROUND

Delayed ischemic neurological deficits (DINDs) contribute to morbidity and mortality following aneurysmal subarachnoid hemorrhage (SAH). Based on promising preliminary reports, some clinicians routinely administer statins to prevent DINDs.

METHODS

Without language restriction, we searched MEDLINE, EMBASE, the Cochrane Central Register, references of review articles, proceedings of the International Stroke Conference, and gray literature sources. Studies were selected if they compared outcomes between statin-treated and untreated patients during the 2 weeks following SAH. Data were extracted and appraised independently and in duplicate, using standardized forms. Fixed or random effects models, as appropriate based on the degree of study heterogeneity, were applied to calculate summary measures.

RESULTS

Four RCTs, two "pseudo" RCTs, five cohort studies, and one case-control study met eligibility criteria. In the RCTs, which enrolled a total of 309 patients, statins were found to significantly reduce the occurrence of DINDs [OR 0.38 (0.23-0.65); P < 0.001], but not mortality [OR 0.51 (0.25-1.02); P = 0.06] or poor neurological recovery [OR 0.81 (0.49-1.32); P = 0.39]. Observational studies assessed 1,542 patients, of whom 385 received statins. Statin-use was not associated with any reduction in DINDs [OR 0.96 (0.71-1.31); P = 0.80], mortality [OR 1.16 (0.78-1.73); P = 0.47] or poor neurological recovery [OR 1.20 (0.84-1.72); P = 0.31]. When the results of all studies were combined, statins had no statistically significant effect.

CONCLUSIONS

Existing RCTs suggest that statins reduce DINDs, with a possible trend toward lower mortality. These findings are not supported by observational research. Although not assessed in all studies, current data do not indicate that statins improve neurological outcomes.

The BELFRAIL (BFC80+) study: a population-based prospective cohort study of the very elderly in Belgium

Background

In coming decades the proportion of very elderly people living in the Western world will dramatically increase. This forthcoming "grey epidemic" will lead to an explosion of chronic diseases. In order to anticipate booming health care expenditures and to assure that social security is funded in the future, research focusing on the relationship between chronic diseases, frailty and disability is needed. The general aim of the BELFRAIL cohort study (BF_C80+) is to study the dynamic interaction between health, frailty and disability in a multi-system approach focusing on cardiac dysfunction and chronic heart failure, lung function, sarcopenia, renal insufficiency and immunosenescence.

Methods/Design

The BF_C80+ is a prospective, observational, population-based cohort study of subjects aged 80 years and older in three well-circumscribed areas of Belgium. In total, 29 general practitioner (GP) centres were asked to include patients aged 80 and older. Only three exclusion criteria were used: severe dementia, in palliative care and medical emergency. Two sampling methods for the recruitment of patients were used. Between November 2, 2008 and September 15, 2009, 567 subjects were included in the BF_C80+ study. Every study participant was invited to undergo four study visits. The GP recorded background variables and medical history and performed a detailed anamnesis and clinical examination. The clinical research assistant performed an extensive examination including performance testing, questionnaires and technical examinations. Echocardiography was performed at home by a cardiologist. A blood sample was collected in the morning. Follow-up reporting of hard outcome measures including mortality, hospitalization and morbidity was organized. A second data collection is planned after 18 months.

Discussion

The BF_C80+ was designed to acquire a better understanding of the epidemiology and pathophysiology of chronic diseases in the very elderly and to study the dynamic interaction between health, frailty and disability in a multi-system approach. The wide variety of dimensions investigated in the BF_C80+ will enable us not only to investigate in depth the relationship between the different physiological systems but also to initiate new research questions based on this unique database of community-dwelling elderly.

Time and spatial distribution of multidrug-resistant tuberculosis among Chinese people, 1981-2006: a systematic review

OBJECTIVES

We aimed to investigate trends in the prevalence of multidrug-resistant tuberculosis (MDR-TB) among Chinese people from first report to 2006, and to detect the high prevalence regions in order to guide control efforts.

MATERIALS AND METHODS

The CBM, VIP, CNKI, and MEDLINE databases were searched through both keywords and subject headings. The literature was screened, and two investigators assessed the quality and extracted the data. Trends in MDR-TB prevalence in three groups--primary, acquired, and combined MDR-TB--were examined separately, using the Cochran-Armitage trend test. Differences were tested with the Kruskal-Wallis test. High prevalence provinces were explored through comparison of the 95% confidence interval (95% CI) with the national average level.

RESULTS

Overall 169 studies were included, with 165 in Chinese and four in English. One hundred and sixteen studies concerned primary MDR-TB, 103 acquired MDR-TB, and 130 combined MDR-TB, with total positive Mycobacterium tuberculosis (MTB) isolates of 110 076, 25 187, and 150 233, respectively. The prevalences of MDR-TB in the three groups in 2005 were 2.64-, 6.20-, and 3.84-times that of 1985, respectively, all showing an upward trend (p<0.05). The prevalences among the three groups were significantly different (p<0.05), with acquired drug resistance (27.5%, 95% CI 26.9-28.1%) much higher than primary drug resistance (4.3%, 95% CI 4.2-4.4%), and combined resistance (9.9%, 95% CI 9.8-10.1%) in between. The top three prevalence regions for primary, acquired, and combined MDR-TB were distributed in the zone from the northeast to the southwest of China, with Hebei, Tibet, and Shanxi having an extremely high prevalence.

CONCLUSIONS

The prevalence of MDR-TB among the Chinese people has shown an upward trend since 1985. It is necessary to continue to monitor this trend in China. Special attention should be paid to provinces distributed in the zone from the northeast to the southwest of China for MDR-TB surveillance, research, and control.

Chiropractic and children: Is more research enough?

Many health science research and review articles end with the words: "More research is needed". However, when it comes to research, it is not as much a question of quantity as of quality. There are a number of important prerequisites before research should be initiated. The three pillars, relevance, quality and ethics should be respected but for a project to be meaningful, it must also be based on plausible rationale.

In evidence-based (informed) practice, one takes into account not only research-based evidence but also clinical expertise and the patients' perspectives. In this paper, we briefly discuss how this should be handled in clinical practice is briefly discussed, using the concept of "traffic lights" (red, yellow, green). We explain how the combination of evidence and plausibility can be used to reach a decision as to whether a treatment or diagnostic procedure is suitable, possible, or unsuitable.

In this thematic series of Chiropractic & Osteopathy a number of reviews are presented, in which the research status of pediatric chiropractic is scrutinized and found wanting. Two important aspects were studied in these reviews: the effect of treatment and safety issues. Two types of problems were identified: the lack of research in general and the lack of research using the appropriate study designs and methodology in particular. Therefore, we discuss the meager research noted in the areas of chiropractic care in children and the clinical consequences this should have. The prerequisites for "more research" are scrutinized and an example given of suitable research programs.

Finally, the important issue of implementation of research findings is covered, emphasizing the responsibility of all stakeholders involved at both the undergraduate and the postgraduate level, within professional associations, and on an individual level.

Prevalence and correlates of inadequate glycaemic control: results from a nationwide survey in 6,671 adults with diabetes in Brazil

Diabetes is a significant public health burden on the basis of its increased incidence, morbidity, and mortality. This study aimed to estimate the prevalence of inadequate glycaemic control and its correlates in a large multicentre survey of Brazilian patients with diabetes. A cross-sectional study was conducted in a consecutive sample of patients aged 18 years or older with either type 1 or type 2 diabetes, attending health centres located in ten large cities in Brazil (response rate = 84%). Information about diabetes, current medications, complications, diet, and satisfaction with treatment were obtained by trained interviewers, using a standardized questionnaire. Glycated haemoglobin (HbA(1c)) was measured by high-performance liquid chromatography in a central laboratory. Patients with HbA(1c) > or = 7 were considered to have inadequate glycaemic control. Overall 6,701 patients were surveyed, 979 (15%) with type 1 and 5,692 (85%) with type 2 diabetes. The prevalence of inadequate glycaemic control was 76%. Poor glycaemic control was more common in patients with type 1 diabetes (90%) than in those with type 2 (73%), P < 0.001. Characteristics significantly associated with improved glycaemic control included: fewer years of diabetes duration, multi professional care, participation in a diabetes health education program, and satisfaction with current diabetes treatment. Despite increased awareness of the benefits of tight glycaemic control, we found that few diabetic patients in Brazil met recommended glycaemic control targets. This may contribute to increased rates of diabetic complications, which may impact health care costs. Our data support the public health message of implementation of early, aggressive management of diabetes.

Type 2 diabetes impairs pulmonary function in morbidly obese women: a case-control study

AIMS/HYPOTHESIS

To determine whether the presence of type 2 diabetes and the degree of metabolic control are related to reduced pulmonary function in obese individuals.

METHODS

Seventy-five morbidly obese women (25 with type 2 diabetes [cases]--and 50 without diabetes [controls]) with a history of non-smoking and without prior cardiovascular or respiratory disease were prospective recruited for a case-control study in the outpatient obesity unit of a referral centre. Both groups were closely matched by age, BMI and waist circumference. Pulmonary function test included forced spirometry and static pulmonary volume measurements.

RESULTS

Type 2 diabetic patients showed lower forced expiratory volume at 1 s (FEV1) (mean difference -11.6% of predicted [95% CI -20.4 to -2.8]; p = 0.011), and FEV1/forced vital capacity (FEV1/FVC) ratio (mean difference -4.4% [95% CI -8.1 to -0.7]; p = 0.049), but a greater residual volume (RV) (mean difference 19.5% of predicted [95% CI 10.8-28.3]; p < 0.001). In addition, an obstructive ventilatory pattern was more frequent in diabetic patients. Significant negative correlations between FEV1 and fasting glucose, HbA1c and HOMA insulin resistance (HOMA-IR) were detected. By contrast, RV was positively correlated with fasting glucose, HbA1c and HOMA-IR. Multiple linear regression analyses showed that fasting glucose and HbA1c independently predicted FEV1 and RV.

CONCLUSIONS/INTERPRETATION

The presence of diabetes and the degree of glycaemic control are related to respiratory function impairment in morbidly obese women. Therefore, the impact of type 2 diabetes on pulmonary function should be taken into consideration by those providing care for obese people.

A retrospective survey of research design and statistical analyses in selected Chinese medical journals in 1998 and 2008

BACKGROUND

High quality clinical research not only requires advanced professional knowledge, but also needs sound study design and correct statistical analyses. The number of clinical research articles published in Chinese medical journals has increased immensely in the past decade, but study design quality and statistical analyses have remained suboptimal. The aim of this investigation was to gather evidence on the quality of study design and statistical analyses in clinical researches conducted in China for the first decade of the new millennium.

METHODOLOGY/PRINCIPAL FINDINGS

Ten (10) leading Chinese medical journals were selected and all original articles published in 1998 (N = 1,335) and 2008 (N = 1,578) were thoroughly categorized and reviewed. A well-defined and validated checklist on study design, statistical analyses, results presentation, and interpretation was used for review and evaluation. Main outcomes were the frequencies of different types of study design, error/defect proportion in design and statistical analyses, and implementation of CONSORT in randomized clinical trials. From 1998 to 2008: The error/defect proportion in statistical analyses decreased significantly ( = 12.03, p<0.001), 59.8% (545/1,335) in 1998 compared to 52.2% (664/1,578) in 2008. The overall error/defect proportion of study design also decreased ( = 21.22, p<0.001), 50.9% (680/1,335) compared to 42.40% (669/1,578). In 2008, design with randomized clinical trials remained low in single digit (3.8%, 60/1,578) with two-third showed poor results reporting (defects in 44 papers, 73.3%). Nearly half of the published studies were retrospective in nature, 49.3% (658/1,335) in 1998 compared to 48.2% (761/1,578) in 2008. Decreases in defect proportions were observed in both results presentation ( = 93.26, p<0.001), 92.7% (945/1,019) compared to 78.2% (1023/1,309) and interpretation ( = 27.26, p<0.001), 9.7% (99/1,019) compared to 4.3% (56/1,309), some serious ones persisted.

CONCLUSIONS/SIGNIFICANCE

Chinese medical research seems to have made significant progress regarding statistical analyses, but there remains ample room for improvement regarding study designs. Retrospective clinical studies are the most often used design, whereas randomized clinical trials are rare and often show methodological weaknesses. Urgent implementation of the CONSORT statement is imperative.

The thrombotic profile of treatment-naive HIV-positive Black South Africans with acute coronary syndromes

BACKGROUND

Patients with human immunodeficiency virus (HIV) infection on protease inhibitors (PIs) have a heightened risk of arterial thrombosis but little is known about treatment-naive patients.

METHODS/RESULTS

Prospective study from South Africa comparing thrombotic profiles of HIV-positive and -negative patients with acute coronary syndrome (ACS). A total of 30 treatment-naive HIV-positive patients with ACS were compared to 30 HIV-negative patients with ACS. Patients with HIV were younger; and besides smoking (73% vs 33%) and low high-density lipoprotein (HDL; 0.8 ± 0.3 vs 1.1 ± 0.4), they had fewer risk factors. Thrombophilia was more common in HIV-positive patients with lower protein C (PC; 82 ± 22 vs 108 ± 20) and higher factor VIII levels (201 ± 87 vs 136 ± 45). Patients with HIV had higher frequencies of anticardiolipin (aCL; 47% vs 10%) and antiprothrombin antibodies (87% vs 21%).

CONCLUSION

Treatment-naive HIV-positive patients with ACS are younger, with fewer traditional risk factors but a greater degree of thrombophilia compared with HIV-negative patients.

Methodological systematic review: mortality in elderly patients with cervical spine injury: a critical appraisal of the reporting of baseline characteristics, follow-up, cause of death, and analysis of risk factors

STUDY DESIGN

Methodologic systematic review.

OBJECTIVE

To determine the validity of reported risk factors for mortality in elderly patients with cervical spine injury.

SUMMARY OF BACKGROUND DATA

In elderly patients with cervical spine injury, mortality has frequently been associated with the type of treatment. To date, however, no review evaluating the validity of reported risk factors for mortality in elderly patients with cervical spine injury has been published.

METHODS

Studies evaluating the treatment of cervical spine injuries in elderly (>/=60 years of age) patients were searched through the Medline and EMBASE databases. In addition to standard methodologic details, reporting of putative confounding baseline characteristics and analysis of risk factors for mortality were appraised critically. For this purpose, patient data presented in included studies were pooled. Exploratory descriptive statistics were used for data analysis.

RESULTS

Twenty-six eligible studies were identified, including a total of 1550 pooled elderly subjects. Except for 2, all studies reported presence or absence of spinal cord injury. Details concerning the severity and/or extent of the injury were reported in 12 (46%) studies. Pre-existing comorbidities were reported in 9 studies (35%). In the pooled subjects, the cause of death was not reported in 155 of 335 deceased patients (42%). Based on own results, 18 (69%) studies reported on risk factors for mortality. Of these studies, 6 (23%) performed statistical analyses of risk factors for mortality outcomes. Only 1 study statistically adjusted potential risk factors for mortality for confounding.

CONCLUSION

Overall, pre-existing comorbidities, concomitant injuries, follow-up and cause of death have been underreported in studies investigating the treatment of cervical spine injuries in elderly patients. To strengthen the validity of risk factors for mortality in future clinical trials, adjustments for appropriately reported putative confounders by regression analysis are mandatory.

Breast cancer in elderly compared to younger patients in the Netherlands: stage at diagnosis, treatment and survival in 127,805 unselected patients

Breast cancer is the most common type of cancer in several parts of the world and the number of elderly patients is increasing. The aim of this study was to describe stage at diagnosis, treatment, and relative survival of elderly patients compared to younger patients in the Netherlands. Adult female patients with their first primary breast cancer diagnosed between 1995 and 2005 were selected. Stage, treatment, and relative survival were described for young and elderly (≥ 65 years) patients and within the cohort of elderly patients according to 5-year age groups. Overall, 127,805 patients were included. Elderly breast cancer patients were diagnosed with a higher stage of disease. Moreover, within the elderly differences in stage were observed. Elderly underwent less surgery (99.2-41.2%); elderly received hormonal treatment as monotherapy more frequently (0.8-47.3%); and less adjuvant systemic treatment (79-53%). Elderly breast cancer patients with breast cancer had a decreased relative survival. Although relative survival was lower in the elderly, the percentage of patients who die of their breast cancer less than 50% above age 75. In conclusion, the relative survival for the elderly is lower as compared to their younger counterparts while the percentage of deaths due to other causes increases with age. This could indicate that the patient selection is poor and fit patients could suffer from "under treatment". In the future, specific geriatric screening tools are necessary to identify fit elderly patients who could receive more "aggressive" treatment while best supportive care should be given to frail elderly patients.

A systematic review of dynamic cerebral and peripheral endothelial function in lacunar stroke versus controls

BACKGROUND AND PURPOSE

The etiology of cerebral small vessel disease is unknown. An association with endothelial dysfunction has been suggested. We systematically assessed all relevant studies of dynamic endothelial function in patients with lacunar stroke as a marker of small vessel disease.

METHODS

We searched for studies of cerebral or peripheral vascular reactivity in patients with lacunar or cortical (ie, large artery atheromatous) ischemic stroke or nonstroke control subjects. We calculated standardized mean difference (SMD) in vascular reactivity+/-95% CIs between small vessel disease and control groups.

RESULTS

Sixteen publications (974 patients) were included. In lacunar stroke, cerebrovascular reactivity (n=534) was reduced compared with age-matched normal (SMD -0.94, 95% CI -1.17 to -0.70), but not age+risk factor-matched control subjects (SMD 0.08, 95% CI -0.36 to 0.53) or cortical strokes (SMD -0.29, 95% CI -0.69 to 0.11); forearm flow-mediated dilatation (n=401) was reduced compared with age-matched normal control subjects (SMD -1.04, 95% CI -1.33 to -0.75) and age+risk factor-matched control subjects (SMD -0.94, 95% CI -1.26 to -0.61), but not cortical strokes (SMD -0.23, 95% CI -0.55 to 0.08).

CONCLUSIONS

Endothelial dysfunction is present in patients with lacunar stroke but may simply reflect exposure to vascular risk factors and having a stroke, because a similar degree of dysfunction is found in cortical (large artery atheromatous) stroke. Current data do not confirm that endothelial dysfunction is specific to small vessel stroke. Future studies should include control subjects with nonlacunar stroke.

Principles of evidence-based medicine

Evidence-based medicine integrates clinical expertise, patients' values and preferences, and the best available evidence from the medical literature. Evidence-based orthopedics is a model to assist surgeons to improve the process of asking questions, obtaining relevant information efficiently, and making informed decisions with patients. With an increasing appreciation for higher levels of evidence, orthopedic surgeons should move away from lower forms of evidence. The adoption of randomized trials and high-quality prospective studies to guide patient care requires 2 prerequisites: (1) greater appreciation for the conduct of randomized trials in orthopedics and (2) improved education and training in evidence-based methodologies in surgery.

Psoriasis and cardiovascular risk: strength in numbers

In this issue, Wakkee and colleagues report a self-described exploratory cohort study and conclude that psoriasis may not be an independent risk factor for ischemic heart disease (IHD) hospitalization and that there is only a slight and borderline increased risk of ischemic heart disease among psoriasis patients. This negative result should be interpreted in light of the study's limitations, the complex relationship among levels of psoriasis severity, patient age, and cardiovascular (CV) risk, and the context of the rapidly growing literature.

How to write and publish an original research article

Most physicians have had little or no exposure to systematic teaching or training during the medical school and residency with respect to writing and publishing an original research article. The framework of every article should include the study objective(s), study design, results, and conclusion(s). The current "Clinical Opinion" article proposes a set of guidelines, based on the authors' experience, which can be useful to junior physicians who plan to publish their work. These guidelines should assist not only in the writing process of the initial manuscript but also in responding to reviews and in modifying the original manuscript.

Outcome of acute kidney injury in severe burns: a systematic review and meta-analysis

PURPOSE

The main objective of this review was to analyse the prevalence and outcome of acute kidney injury (AKI) in patients with severe burn injury. AKI is a common complication in patients with severe burn injury and one of the major causes of death (often combined with other organ dysfunctions). Several definitions of AKI have been used, but the RIFLE 'consensus' classification is nowadays considered the gold standard, enabling a more objective comparison of populations.

METHODS

We performed a systematic literature search (1960-2009), involving PubMed, the Web of Science, the search engine Google and textbooks. Reference lists and the Science Citation Index search were also consulted. Attributable mortality was assessed by performing a meta-analysis.

RESULTS

This search yielded 57 articles and abstracts with relevant epidemiologic data of AKI in the burn population. Of these, 30 contained complete mortality data of the burn and control population, which revealed a 3- to 6-fold higher mortality for AKI patients in univariate analysis, depending on the applied definition. When defined by the RIFLE consensus classification, AKI occurred in one quarter of patients with severe burn injury (median mortality of 34.9%), and when defined by the need for renal replacement therapy (RRT), AKI occurred in 3% (median mortality of 80%). The prevalence of AKI slightly increased, but AKI-RRT decreased. However, the outcome in both groups improved.

CONCLUSION

Despite the wide variation of the analysed burn populations and definitions of AKI, this review clearly showed that AKI remains prevalent and is associated with increased mortality in patients with severe burn injury.

Association between helicobacter pylori and gastrointestinal symptoms in children

OBJECTIVE

Recurrent abdominal pain (RAP) and other gastrointestinal (GI) symptoms are common complaints among children. The role of Helicobacter pylori in the cause of these complaints remains controversial. Nevertheless, there is an increasing pressure on primary care clinicians to screen for H pylori infection in symptomatic children. We systematically reviewed the published evidence for an association between H pylori infection and GI symptoms in children.

METHODS

Medline and Embase databases up to July 2009 were searched to identify studies that evaluated the association between H pylori and GI symptoms in children aged up to 18 years. When studies reported on abdominal pain without additional definition, thus not fulfilling Apley's criteria, we grouped these outcomes as unspecified abdominal pain (UAP). Methodologic quality was scored by using a standardized list of criteria, and crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated and pooled.

RESULTS

Thirty-eight studies met our inclusion criteria: 23 case-control studies, 14 cross-sectional studies, and 1 prospective cohort study. The overall methodologic quality was low. Pooled ORs for the association between RAP and H pylori infection in children were 1.21 (95% CI: 0.82-1.78) in 12 case-control studies and 1.00 (95% CI: 0.76-1.31) in 7 cross-sectional studies. Meta-analysis of the association between UAP and H pylori infection in 6 hospital-based studies resulted in a pooled OR of 2.87 (95% CI: 1.62-5.09) compared with 0.99 (95% CI: 0.46-2.11) in 5 population-based studies. Two of 3 studies concerning epigastric pain reported a statistically significant positive association with H pylori infection.

CONCLUSIONS

We found no association between RAP and H pylori infection in children and conflicting evidence for an association between epigastric pain and H pylori infection. We found evidence for an association between UAP but could not confirm this finding in children seen in primary care.

Extended antibiotic prophylaxis for prevention of surgical-site infections in morbidly obese women who undergo combined hysterectomy and medically indicated panniculectomy: a cohort study

OBJECTIVE

The purpose of this study was to compare surgical-site infection rates in obese women who had extended prophylactic antibiotic (EPA) vs standard prophylactic antibiotic.

STUDY DESIGN

An electronic records-linkage system identified 145 obese women (body mass index, >30 kg/m(2)) who underwent combined hysterectomy and panniculectomy from January 1, 2005, through December 31, 2008. The EPA cohort received standard antibiotics (cefazolin, 2 g) and continued oral antibiotic (ciprofloxacin) until removal of drains. Regression models were used to adjust for known confounders.

RESULTS

The mean age was 56.0 + or - 12.1 years, and mean body mass index was 42.6 + or - 8.4 kg/m(2) (range, 30-86.4 kg/m(2)). The EPA cohort experienced fewer surgical-site infections (6 [5.9%] vs 12 [27.9%]; P < .001; adjusted odds ratio, 0.16; 95% confidence interval, 0.04-0.51; P < .001), had lower probability of incision and drainage (3 [2.9%] vs 5 [11.6%]; P = .05), and required fewer infection-related admissions (5 [4.9%] vs 6 [13.9%]; P = .08).

CONCLUSION

Extended antibiotic prophylaxis can reduce surgical-site infections in obese women after combined hysterectomy and panniculectomy.