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

Improving outcome prediction of systemic sclerosis from isolated Raynaud's phenomenon: role of autoantibodies and nail-fold capillaroscopy

OBJECTIVE

A simple weighted prognostic algorithm, based on capillaroscopy and autoantibodies, is developed to classify patients at different risk of transition from isolated RP to SSc within 5 years from the screening visit.

METHODS

Two hundred and eighty-eight of 768 patients with isolated RP who underwent capillaroscopy were recruited. The prognostic contributions of capillaroscopic findings (giant loops, haemorrhages and the number of capillaries) and SSc-associated autoantibodies (ACAs, anti-topo I and ANAs) were assessed in a semi-parametric regression models suitable for competing risks. A prognostic index was built by a bagging technique. A structured tree approach was used to extract simple classificatory rules that can be directly interpreted.

RESULTS

Thirty-four transitions from isolated RP to SSc and 42 to other CTDs were observed. All of the chosen variables had a substantial prognostic impact. A complex non-linear prognostic pattern was observed for capillaries, with the risk of developing SSc increasing as the number of loops decreased. The presence of ANAs had a strong impact on prognosis [hazard ratio (HR) = 9.70], which was increased by the presence of ACA (HR = 3.94; P < 0.001). A weighted prognostic classification for the development of SSc was constructed using capillary number, giant loops and ANAs. The prognostic discrimination was satisfactory (Harrell's C-index = 0.86).

CONCLUSION

Our prognostic model is based on easy-to-obtain features (i.e. the number of capillaries, giant loops and ANAs) and could be used to facilitate clinical decision making in the screening phase, and may also have important implications for stratifying patients into risk groups for future clinical assessment.

Anxiety is a better predictor of platelet reactivity in coronary artery disease patients than depression

AIMS

Depression and anxiety are linked to coronary events but the mechanism(s) remains unclear. We investigated the associations of depression and anxiety with serotonin-mediated platelet hyperactivity in coronary artery disease (CAD) patients in a cross-sectional study.

METHODS AND RESULTS

Three months after an acute coronary event, stable CAD patients (n = 83) on aspirin and clopidogrel were evaluated for depression (beck depression inventory) and anxiety (hospital anxiety and depression scale), and their platelet reactivity was measured (optical aggregometry and flow cytometric fibrinogen binding in response to adenosine diphosphate (ADP = 5 microM) and two serotonin + epinephrine doses [5HT:E (L) = 4 microM + 4 microM and 5HT:E (H) = 10 microM + 4 microM]. Platelet reactivity was significantly higher in depressed and anxious than in depressed only or non-depressed-and-non-anxious patients. Aggregation (mean +/- SE) was 41.9 +/- 2.6% vs. 32.2 +/- 2.6% vs. 30.4 +/- 3.7% with 5HT:E (L) and 46.9 +/- 2.7% vs. 35.6 +/- 2.7% vs. 31.7 +/- 3.8% with 5HT:E (H) (P < 0.05 for both). Differences in ADP aggregations were not significant, perhaps because of clopidogrel therapy. Flow cytometry findings were similar. In a multivariate linear regression model adjusted for age, body mass index, and each other, anxiety symptoms independently predicted all 5HT:E-mediated platelet reactivity measures, whereas depression predicted none.

CONCLUSION

Anxiety is associated with elevated serotonin-mediated platelet reactivity in stable CAD patients and symptoms of anxiety show strong, independent correlations with platelet function.

The relationship between anti-merozoite antibodies and incidence of Plasmodium falciparum malaria: A systematic review and meta-analysis

BACKGROUND

One of the criteria to objectively prioritize merozoite antigens for malaria vaccine development is the demonstration that naturally acquired antibodies are associated with protection from malaria. However, published evidence of the protective effect of these antibodies is conflicting.

METHODS AND FINDINGS

We performed a systematic review with meta-analysis of prospective cohort studies examining the association between anti-merozoite immunoglobin (Ig) G responses and incidence of Plasmodium falciparum malaria. Two independent researchers searched six databases and identified 33 studies that met predefined inclusion and quality criteria, including a rigorous definition of symptomatic malaria. We found that only five studies were performed outside sub-Saharan Africa and that there was a deficiency in studies investigating antibodies to leading vaccine candidates merozoite surface protein (MSP)-1(42) and erythrocyte binding antigen (EBA)-175. Meta-analyses of most-studied antigens were conducted to obtain summary estimates of the association between antibodies and incidence of P. falciparum malaria. The largest effect was observed with IgG to MSP-3 C terminus and MSP-1(19) (responders versus nonresponders, 54%, 95% confidence interval [CI] [33%-68%] and 18% [4%-30%] relative reduction in risk, respectively) and there was evidence of a dose-response relationship. A tendency towards protective risk ratios (RR<1) was also observed for individual study estimates for apical membrane antigen (AMA)-1 and glutamate-rich protein (GLURP)-R0. Pooled estimates showed limited evidence of a protective effect for antibodies to MSP-1 N-terminal regions or MSP-1-EGF (epidermal growth factor-like modules). There was no significant evidence for the protective effect for MSP-2 (responders versus nonresponders pooled RR, MSP-2(FC27) 0.82, 95% CI 0.62-1.08, p = 0.16 and MSP-2(3D7) 0.92, 95% CI 0.75-1.13, p = 0.43). Heterogeneity, in terms of clinical and methodological diversity between studies, was an important issue in the meta-analysis of IgG responses to merozoite antigens.

CONCLUSIONS

These findings are valuable for advancing vaccine development by providing evidence supporting merozoite antigens as targets of protective immunity in humans, and to help identify antigens that confer protection from malaria. Further prospective cohort studies that include a larger number of lead antigens and populations outside Africa are greatly needed to ensure generalizability of results. The reporting of results needs to be standardized to maximize comparability of studies. We therefore propose a set of guidelines to facilitate the uniform reporting of malaria immuno-epidemiology observational studies. Please see later in the article for the Editors' Summary.

Retrospective descriptive analysis of 1,176 patients with failed hypospadias repair

PURPOSE

To our knowledge epidemiological data on the incidence of failed hypospadias repair and the number of patients seeking further surgical treatment remain unknown. We report an observational, descriptive survey of patients who were evaluated and treated for urethral stricture disease and/or penile defects after primary hypospadias repair.

MATERIALS AND METHODS

We performed a retrospective observational chart analysis of patients evaluated and treated for urethral stricture disease and/or penile defects at 2 tertiary European centers from January 1998 to December 2007. In each case we investigated the primary abnormal meatal site, the number of operations needed to repair primary hypospadias and complications of this primary repair. Patients were offered surgical repair for previous failed hypospadias treatment. After surgery evaluation was scheduled at 3, 6 and 9 months. Success was defined as a functional urethra without fistula, stricture or residual chordee and a cosmetically acceptable glanular meatus after the completion of all secondary procedures.

RESULTS

A total of 1,176 patients with a mean age of 31 years were evaluated and treated. To treat failed hypospadias repair 760 (64.6%) and 416 patients (35.4%) underwent 1-stage and staged repair, respectively. Mean followup was 60.4 months. Of 1,176 cases 1,036 (88.1%) were classified as successful and 140 (11.9%) were considered failures.

CONCLUSIONS

Failed hypospadias repair may be corrected by multiple and complex surgeries. Its effects are experienced during the lifetime of the patient and parents.

Soluble ST2 for predicting sudden cardiac death in patients with chronic heart failure and left ventricular systolic dysfunction

OBJECTIVES

We studied whether the measurement of the soluble form of ST2 (sST2), an interleukin-1 receptor family member, could identify heart failure (HF) patients at risk of sudden cardiac death (SCD).

BACKGROUND

The prediction of SCD remains an important challenge in patients with mild-to-moderate chronic HF. Concentrations of sST2 have been found increased and related to worse long-term outcomes in patients with acute HF. Whether sST2 has a prognostic role in SCD is unknown.

METHODS

A nested case-control study was performed on 36 cases of SCD and 63 control patients (matched for age, sex, and left ventricular ejection fraction) obtained from the MUSIC (MUerte Súbita en Insuficiencia Cardíaca) registry, a 3-year multicenter registry of ambulatory HF patients (New York Heart Association functional class II to III, left ventricular ejection fraction < or =45%). Demographic, clinical, echocardiographic, electrical, and biochemical data were collected at enrollment.

RESULTS

Concentrations of sST2 were greater among decedents (0.23 ng/ml [interquartile range 0.16 to 0.43 ng/ml] vs. 0.12 ng/ml [interquartile range 0.06 to 0.23 ng/ml], p = 0.001) and were predictive of experiencing SCD (+0.1 ng/ml, odds ratio: 1.39, 95% confidence interval: 1.09 to 1.78, p = 0.006). On the basis of a combined biomarker status, only 4% of patients experienced SCD for neither sST2 nor N-terminal pro-B-type natriuretic peptide (NT-proBNP) above receiver-operator characteristic-derived cut-off points (0.15 ng/ml and 2,000 ng/l, respectively), 34% for either biomarker above, and 71% for both biomarkers above (p < 0.001 for trend). This combined variable added incremental prognostic value to the multivariable regression model (p < 0.001).

CONCLUSIONS

Elevated sST2 concentrations are predictive of SCD in patients with chronic HF and provide complementary information to NT-proBNP levels. A combined biomarker approach may have an impact on clinical decision-making.

Improved reporting of statistical design and analysis: guidelines, education, and editorial policies

A majority of original articles published in biomedical journals include some form of statistical analysis. Unfortunately, many of the articles contain errors in statistical design and/or analysis. These errors are worrisome, as the misuse of statistics jeopardizes the process of scientific discovery and the accumulation of scientific knowledge. To help avoid these errors and improve statistical reporting, four approaches are suggested: (1) development of guidelines for statistical reporting that could be adopted by all journals, (2) improvement in statistics curricula in biomedical research programs with an emphasis on hands-on teaching by biostatisticians, (3) expansion and enhancement of biomedical science curricula in statistics programs, and (4) increased participation of biostatisticians in the peer review process along with the adoption of more rigorous journal editorial policies regarding statistics. In this chapter, we provide an overview of these issues with emphasis to the field of molecular biology and highlight the need for continuing efforts on all fronts.

Patients with severe psoriasis are at increased risk of cardiovascular mortality: cohort study using the General Practice Research Database

AIMS

Psoriasis is a common chronic inflammatory T-helper cell-1/17 mediated skin disease. Recent studies suggest that psoriasis, particularly if severe, may be an independent risk factor for atherosclerosis, myocardial infarction (MI), and stroke. We conducted a cohort study using the General Practice Research Database to determine if severe psoriasis patients have an increased risk of cardiovascular (CV) mortality.

METHODS AND RESULTS

Severe psoriasis was defined as patients who received a psoriasis diagnosis and systemic therapy consistent with severe psoriasis (n = 3603). Up to four unexposed patients without psoriasis were selected from the same practices and start dates for each psoriasis patient (n = 14 330). For every death, the cause was determined by review of the electronic medical record. Severe psoriasis was an independent risk factor for CV mortality (HR 1.57; 95% CI 1.26, 1.96) when adjusting for age, sex, smoking, diabetes, hypertension, and hyperlipidaemia. Overall, severe psoriasis patients experienced one extra CV death per 283 patients per year, even when adjusting for major CV risk factors. The relative risk of CV mortality was modified by age. For example, the RR of CV death for a 40-year-old and 60-year-old with severe psoriasis was 2.69 (1.45, 4.99) and 1.92 (1.41, 2.62), respectively. The findings were robust to multiple sensitivity analyses.

CONCLUSION

Patients with severe psoriasis have an increased risk of CV mortality that is independent of traditional CV risk factors. Additional studies are needed to determine the mechanism of this association and the impact that control of psoriasis has on CV risk.

Acute coronary syndromes in treatment-naïve black South africans with human immunodeficiency virus infection

BACKGROUND

HIV patients on protease inhibitors have greater risk of acute coronary syndromes (ACS) but little is known about treatment-naïve patients.

METHODS AND RESULTS

Authors conducted a prospective single-center study from Soweto, South Africa, comparing the clinical and angiographic features of treatment-naïve HIV positive and negative patients with ACS. Between March 2004 and February 2008, 30 consecutive treatment-naïve HIV patients with ACS were compared to the next HIV-negative patient as a 1:1 control. HIV patients were younger (43 +/- 7 vs. 54 +/- 13, P = 0.004) and, besides smoking (73% vs. 33%, P = 0.002), had fewer risk factors than the control group with less hypertension (23% vs. 77%, P = 0.0001), diabetes (3% vs. 23%, P = 0.05), LDL hyperlipidemia (2.2 +/- 0.9 vs. 3.0 +/- 1.2, P = 0.006), and other coronary risk factors (7% vs. 53%, P = 0.0001). HDL was lower in the HIV group (0.8 +/- 0.3 vs. 1.1 +/- 0.4, P = 0.001). Atherosclerotic burden was lower in the HIV group with more normal infarct-related arteries (47% vs. 13%, P = 0.005) but a higher degree of large thrombus burden (43% vs. 17%, P = 0.02). Stents were used to a similar degree in HIV and control patients (30% vs. 37%, P = 0.78) with more target lesion revascularization in the HIV group (56% vs. 0%, P = 0.008).

CONCLUSION

Treatment-naïve HIV patients with ACS are younger and have fewer traditional risk factors than HIV-negative patients. HIV patients have less atherosclerotic but higher thrombotic burden which may imply a prothrombotic state in the pathogenesis of ACS in these patients.

Methodology and analytic techniques used in clinical research: associations with journal impact factor

OBJECTIVE

To describe research methodology and statistical reporting of published articles in high-impact-factor general medical journals compared with moderate-impact-factor obstetrics and gynecology journals.

METHODS

A cross-sectional analysis was performed on 371 articles published from January to June 2006 in six journals (high-impact-factor group: Journal of the American Medical Association, The Lancet, the New England Journal of Medicine; moderate-impact-factor group-American Journal of Obstetrics & Gynecology, British Journal of Obstetrics and Gynaecology, and Obstetrics & Gynecology). Articles were classified by level of evidence. Data abstracted from each article included number of authors, clearly stated hypothesis, sample size/power calculations, statistical measures, and use of regression analysis. Univariable analyses were performed to evaluate differences between the high-impact-factor and moderate-impact-factor groups.

RESULTS

The majority of published reports were observational studies (50%), followed by randomized controlled trials ([RCTs] 24%), case reports (14%), systematic reviews (6%), case series (1%), and other study types (4%). Within the high-impact-factor group, 35% were RCTs compared with 12% in the moderate-impact-factor group (relative risk 2.9, 95% confidence interval 1.9-4.4). Recommended statistical reporting (eg, point estimates with measures of precision) was more common in the high-impact-factor group (P<.005).

CONCLUSION

The proportion of RCTs published among the high-impact-factor group was three times that of the moderate group. Efforts to provide the highest level of evidence and statistical reporting have the potential to improve the quality of reports in the medical literature available for clinical decision making.

LEVEL OF EVIDENCE

III.

Survey of the quality of experimental design, statistical analysis and reporting of research using animals

For scientific, ethical and economic reasons, experiments involving animals should be appropriately designed, correctly analysed and transparently reported. This increases the scientific validity of the results, and maximises the knowledge gained from each experiment. A minimum amount of relevant information must be included in scientific publications to ensure that the methods and results of a study can be reviewed, analysed and repeated. Omitting essential information can raise scientific and ethical concerns. We report the findings of a systematic survey of reporting, experimental design and statistical analysis in published biomedical research using laboratory animals. Medline and EMBASE were searched for studies reporting research on live rats, mice and non-human primates carried out in UK and US publicly funded research establishments. Detailed information was collected from 271 publications, about the objective or hypothesis of the study, the number, sex, age and/or weight of animals used, and experimental and statistical methods. Only 59% of the studies stated the hypothesis or objective of the study and the number and characteristics of the animals used. Appropriate and efficient experimental design is a critical component of high-quality science. Most of the papers surveyed did not use randomisation (87%) or blinding (86%), to reduce bias in animal selection and outcome assessment. Only 70% of the publications that used statistical methods described their methods and presented the results with a measure of error or variability. This survey has identified a number of issues that need to be addressed in order to improve experimental design and reporting in publications describing research using animals. Scientific publication is a powerful and important source of information; the authors of scientific publications therefore have a responsibility to describe their methods and results comprehensively, accurately and transparently, and peer reviewers and journal editors share the responsibility to ensure that published studies fulfil these criteria.

Optical diagnosis of small colorectal polyps at routine colonoscopy (Detect InSpect ChAracterise Resect and Discard; DISCARD trial): a prospective cohort study

BACKGROUND

Accurate optical diagnosis of small (<10 mm) colorectal polyps in vivo, without formal histopathology, could make colonoscopy more efficient and cost effective. The aim of this study was to assess whether optical diagnosis of small polyps is feasible and safe in routine clinical practice.

METHODS

Consecutive patients with a positive faecal occult blood test or previous adenomas undergoing surveillance at St Mark's Hospital (London, UK), from June 19, 2008, to June 16, 2009, were included in this prospective study. Four colonoscopists with different levels of experience predicted polyp histology using optical diagnosis with high-definition white light, followed by narrow-band imaging without magnification and chromoendoscopy, as required. The primary outcome was accuracy of polyp characterisation using optical diagnosis compared with histopathology, the current gold standard. Accuracy of optical diagnosis to predict the next surveillance interval was also assessed and compared with surveillance intervals predicted by current guidelines using histopathology. This study is registered with ClinicalTrials.gov, NCT00888771.

FINDINGS

363 polyps smaller than 10 mm were detected in 130 patients, of which 278 polyps had both optical and histopathological diagnosis. By histology, 198 of these polyps were adenomas and 80 were non-neoplastic lesions (of which 62 were hyperplastic). Optical diagnosis accurately diagnosed 186 of 198 adenomas (sensitivity 0.94; 95% CI 0.90-0.97) and 55 of 62 hyperplastic polyps (specificity 0.89; 0.78-0.95), with an overall accuracy of 241 of 260 (0.93, 0.89-0.96) for polyp characterisation. Using optical diagnosis alone, 82 of 130 patients could be given a surveillance interval immediately after colonoscopy, and the same interval was found after formal histopathology in 80 patients (98%) using British guidelines and in 78 patients (95%) using US multisociety guidelines.

INTERPRETATION

For polyps less than 10 mm in size, in-vivo optical diagnosis seems to be an acceptable strategy to assess polyp histopathology and future surveillance intervals. Dispensing with formal histopathology for most small polyps found at colonoscopy could improve the efficiency of the procedure and lead to substantial savings in time and cost.

FUNDING

Leigh Family Trust, London, UK.

Ultrasonographic hepatic steatosis increases prediction of mortality risk from elevated serum gamma-glutamyl transpeptidase levels

The aim of the present study was to investigate the association of serum gamma-glutamyltransferase (GGT) levels with all-cause mortality and to assess the impact of ultrasonographic findings of hepatic hyperechogenicity in that association. We used data from 4,160 subjects (2,044 men and 2,116 women) recruited for the population-based Study of Health in Pomerania (SHIP) without baseline hepatitis B and C infections or liver cirrhosis. GGT was divided into age- and sex-dependent quintiles to calculate overall and sex-specific crude incidence mortality rates. Hepatic steatosis was defined by elevated GGT levels (>80%) and the presence of hyperechogenic liver ultrasound. We used multiple-adjusted Cox proportional hazards regression models, first, to assess the direct effect of GGT on all-cause mortality, second, to stratify according to the ultrasonographic finding, and third, to investigate potential mediating effects of cardiometabolic risk factors. During 29,810 person-years (7.3 years, median) of follow-up, 307 individuals (7.5%) died, resulting in a death rate of 0.86 deaths per 1000 person-years. Elevated GGT levels were associated with increased risk of mortality in men (hazard ratio [HR] 1.49; 95% confidence interval [CI], 1.08-2.05), but not in women (HR 1.30; 95% CI, 0.80-2.12). This association was even stronger in men with hepatic steatosis (HR 1.98; 95% CI, 1.21-3.27). Cause-specific mortality analysis by cardiovascular disease deaths confirmed the sex-specific association. Adjustment for cardiometabolic risk factors did not affect the estimates.

CONCLUSION

In the case of increased GGT levels, liver ultrasound should be performed, not only for diagnosis, but also for further risk stratification.

Mortality among amphetamine users: a systematic review of cohort studies

AIMS

To report the results of a comprehensive literature search of studies of mortality among people who use amphetamines.

DESIGN AND SETTING

Three electronic databases were searched (EMBASE, Medline and PsycINFO) and "grey" literature was located. Shortlists of papers were circulated to experts to ascertain whether any important papers had been missed. Papers were hand-searched to retrieve any additional relevant articles.

MEASUREMENTS

Studies meeting inclusion criteria were prospective cohort studies examining mortality risk among dependent and problematic amphetamine users. Crude mortality rates (CMR/100PY) and standardised mortality ratios (SMRs) were the primary outcome measures considered. Data on overall mortality, and rates for specific causes of death, were of interest.

FINDINGS

2187 articles and 9 grey literature sources were obtained. After thorough review, 72 articles were identified as reporting on amphetamine-related mortality, 7 provided data from cohort studies of users. An additional study of Swedish military conscripts was identified by the authors during correspondence with other researchers. The geographic spread of cohorts was restricted to high income countries with the exception of one Thai study; reporting of standard parameters in mortality studies was often sparse. The estimated CMRs ranged from 0 in Australia to 2.95 (1.46-4.59) in Thailand. The Czech cohort reported the only SMR: 6.22 overall, males: 5.87, females: 7.84.

CONCLUSIONS

Given the widespread use of amphetamines, the known non-fatal adverse effects of use and the mortality rates reported here, cohort studies investigating the morbidity and mortality associated with such drug use should be a research priority.

Psoriasis may not be an independent risk factor for acute ischemic heart disease hospitalizations: results of a large population-based Dutch cohort

Although psoriasis has been associated with components of the metabolic syndrome, its association with myocardial infarction is less clear. A cohort study was conducted using hospital and pharmacy records of 2.5 million Dutch residents between 1997 and 2008. The risk of ischemic heart disease (IHD) hospitalizations was compared between psoriasis patients and a matched reference cohort. Additional adjustments were made for healthcare consumption and use of cardiovascular drugs. A total of 15,820 psoriasis patients and 27,577 reference subjects were included, showing an incidence rate of 611 and 559 IHD per 100,000 person-years, respectively (P=0.066). The age- and gender-adjusted risk of IHD was comparable between both cohorts (hazard ratio (HR)=1.10, 95% confidence interval 0.99-1.23). Before cohort entry, psoriasis patients used more antihypertensive, antidiabetic, and lipid-lowering drugs and were more often hospitalized. Adjusting for these confounders decreased the HR for IHD, but it remained comparable between both populations. There was no different risk of IHD between the subgroup of patients who only used topicals versus those who received systemic therapies or inpatient care for their psoriasis. This study, therefore, suggests that psoriasis is not a clinically relevant risk factor for IHD hospitalizations on the population level.

Calibration and discriminatory accuracy of prognosis calculation for breast cancer with the online Adjuvant! program: a hospital-based retrospective cohort study

BACKGROUND

Adjuvant! is a web-based program that calculates individualised 10-year survival probabilities and predicted benefit of adjuvant systemic therapy. The Adjuvant! model has not been validated in any large European series. The aim of our study was to validate Adjuvant! in Dutch patients, investigating both its calibration and discriminatory accuracy.

METHODS

Patients who were at least partly treated at the Netherlands Cancer Institute for breast cancer between 1987 and 1998 were included if they met the following criteria: tumour size T1 (< or =2 cm), T2 (2-5 cm), or T3 (>5 cm), invasive breast carcinoma, with information about involvement of axillary lymph nodes available, no distant metastases, primary surgery, axillary staging, and radiotherapy according to national guidelines. Clinicopathological characteristics and adjuvant treatment data were retrieved from hospital records and medical registries and were entered into the Adjuvant! (version 8.0) batch processor with blinding to outcome. Endpoints were overall survival and the proportion of patients that did not die from breast cancer (breast-cancer-specific survival [BCSS]).

FINDINGS

5380 patients were included with median follow-up of 11.7 years (range 0.03-21.8). The 10-year observed overall survival (69.0%) and BCSS (78.6%) and Adjuvant! predicted overall survival (69.1%) and BCSS (77.8%) were not statistically different (p=0.87 and p=0.18, respectively). Moreover, differences between predicted and observed outcomes were within 2% for most relevant clinicopathological subgroups. In patients younger than 40 years, Adjuvant! overestimated overall survival by 4.2% (p=0.04) and BCSS by 4.7% (p=0.01). The concordance index, which indicates discriminatory accuracy at the individual level, was 0.71 for BCSS in the entire cohort.

INTERPRETATION

Adjuvant! accurately predicted 10-year outcomes in this large-scale Dutch validation study and is of use for adjuvant treatment decision making, although the results may be less reliable in some subgroups.

Prevalence, characteristics and severity of non-alcoholic fatty liver disease in patients with chronic plaque psoriasis

BACKGROUND/AIMS

The association between NAFLD and psoriasis has never been explored in prospective epidemiological studies. The aim of this 2-phase study was to study the clinical features of NAFLD in patients with psoriasis.

METHODS

Phase 1: Investigation of prevalence and characteristics of NAFLD in an unselected cohort of 142 adult Italian outpatients with psoriasis vulgaris. Phase 2: Comparison of the psoriasis cohort subgroup with NAFLD and an age- and body mass index-matched retrospective cohort of 125 non-psoriasis patients with biopsy proven NAFLD.

RESULTS

Based on histories, laboratory tests, and ultrasound studies, 84 (59.2%) received clinical diagnosis of NAFLD; 30 had factors potentially associated with liver disease other than NAFLD (e.g., viral hepatitis, significant ethanol, methotrexate use); and 28 (19.7%) had normal livers. Comparison of the normal-liver and NAFLD subgroups revealed that NAFLD in psoriasis patients (Ps-NAFLD) was significantly correlated with metabolic syndrome (p<0.05); obesity (p=0.043); hypercholesterolemia (p=0.029); hypertriglyceridemia (p<0.001); AST/ALT ratio >1 (p=0.019), and psoriatic arthritis (PsA) (p=0.036). The association with PsA remained significant after logistic regression analysis (OR=3.94 [CI, 1.07-14.46]). Compared with the retrospective non-psoriatic NAFLD cohort (controls), Ps-NAFLD patients (cases) were likely to have severe NAFLD reflected by non-invasive NAFLD Fibrosis Scores and AST/ALT >1.

CONCLUSIONS

NAFLD is highly prevalent among psoriasis patients, where it is closely associated with obesity (overall and abdominal), metabolic syndrome, and PsA, and more likely to cause severe liver fibrosis (compared with nonPs-NAFLD). Routine work-up for NAFLD may be warranted in patients with psoriasis, especially when potentially hepatotoxic drug therapy is being considered.

A simple tool to measure patient perceptions of operative birth

OBJECTIVE

To assess the feasibility and validity of a maternal satisfaction measurement tool, the SaFE study Patient Perception Score (PPS), after operative delivery.

DESIGN

Cross-sectional survey.

SETTING

A large maternity unit in England.

SAMPLE

150 women who had had an operative birth.

METHODS

We recruited women within 24 hours of birth and quantified their satisfaction with two questionnaires: PPS, and the Mackey Childbirth Satisfaction Rating Scale (CSRS; modified).

MAIN OUTCOME MEASURES

Participation rate to determine feasibility; Cronbach's alpha as measure of internal consistency; PPS satisfaction scores for groups of accoucheurs of different seniority to assess construct validity; correlation coefficient of PPS scores with total scores from the CSRS questionnaire to establish criterion validity.

RESULTS

Participation rate approached 85%. We observed high scores for most births except a few outliers. Internal consistency of the PPS was high (Cronbach's alpha=0.83). Total PPS scores correlated strongly with total CSRS scores (Spearman's r=0.64, P<0.001).

CONCLUSIONS

The PPS is a simple and valid tool for patient-centred assessments. High scores were observed for most births but there were a small minority of accoucheurs who consistently scored poorly and these data could be used during appraisal and training.

Autologous hematopoietic stem cell transplantation for autoimmune diseases: an observational study on 12 years' experience from the European Group for Blood and Marrow Transplantation Working Party on Autoimmune Diseases

BACKGROUND

Autologous hematopoietic stem cell transplantation has been used since 1996 for the treatment of severe autoimmune diseases refractory to approved therapies. We evaluated the long-term outcomes of these transplants and aimed to identify potential prognostic factors.

DESIGN AND METHODS

In this observational study we analyzed all first autologous hematopoietic stem cell transplants for autoimmune diseases reported to the European Group for Blood and Marrow Transplantation (EBMT) registry between 1996-2007. The primary end-points for analysis were overall survival, progression-free survival and transplant-related mortality at 100 days.

RESULTS

Nine hundred patients with autoimmune diseases (64% female; median age, 35 years) who underwent a first autologous hematopoietic stem cell transplant were included. The main diseases were multiple sclerosis (n=345), systemic sclerosis (n=175), systemic lupus erythematosus (n=85), rheumatoid arthritis (n=89), juvenile arthritis (n=65), and hematologic immune cytopenia (n=37). Among all patients, the 5-year survival was 85% and the progression-free survival 43%, although the rates varied widely according to the type of autoimmune disease. By multivariate analysis, the 100-day transplant-related mortality was associated with the transplant centers' experience (P=0.003) and type of autoimmune disease (P=0.03). No significant influence of transplant technique was identified. Age less than 35 years (P=0.004), transplantation after 2000 (P=0.0015) and diagnosis (P=0.0007) were associated with progression-free survival.

CONCLUSIONS

This largest cohort studied worldwide shows that autologous hematopoietic stem cell transplantation can induce sustained remissions for more than 5 years in patients with severe autoimmune diseases refractory to conventional therapy. The type of autoimmune disease, rather than transplant technique, was the most relevant determinant of outcome. Results improved with time and were associated with the transplant centers' experience. These data support ongoing and planned phase III trials to evaluate the place of autologous hematopoietic stem cell transplantation in the treatment strategy for severe autoimmune diseases.

Estimating the burden of disease attributable to illicit drug use and mental disorders: what is 'Global Burden of Disease 2005' and why does it matter?

BACKGROUND

The estimated impact of illicit drug use and mental disorders upon population health needs to be understood because there is evidence that they produce substantial loss of life and disability, and information is needed on the comparative population health impact of different diseases and risk factors to help focus policy, service and research planning and execution.

AIMS

To provide an overview of a global project, running since the end of 2007-Global Burden of Disease (GBD) 2005.

METHODS

The new GBD aims to update comprehensively the findings of the first GBD exercise. It aims to provide regional and global estimates of the burden of disease attributable to hundreds of diseases, injuries and their risk factors. Groups have been assembled to provide expert advice on the parameters needed to inform these estimates; here, we provide a brief summary of the broad range of work being undertaken by the group examining illicit drug use and mental disorders.

DISCUSSION

The estimates of the contribution of mental disorders and illicit drugs to GBD will inform and potentially shape the focus of researchers, clinicians and governments in the years to come. We hope that interested readers might be encouraged to submit new data or feedback on the work completed thus far, as well as the work that is still under way and yet to be completed.

Inflammatory markers and poor outcome after stroke: a prospective cohort study and systematic review of interleukin-6

BACKGROUND

The objective of this study was to determine whether: (a) markers of acute inflammation (white cell count, glucose, interleukin-6, C-reactive protein, and fibrinogen) are associated with poor outcome after stroke and (b) the addition of markers to previously validated prognostic models improves prediction of poor outcome.

METHODS AND FINDINGS

We prospectively recruited patients between 2002 and 2005. Clinicians assessed patients and drew blood for inflammatory markers. Patients were followed up by postal questionnaire for poor outcome (a score of>2 on the modified Rankin Scale) and death through the General Register Office (Scotland) at 6 mo. We performed a systematic review of the literature and meta-analysis of the association between interleukin-6 and poor outcome after stroke to place our study in the context of previous research. We recruited 844 patients; mortality data were available in 844 (100%) and functional outcome in 750 (89%). After appropriate adjustment, the odds ratios for the association of markers and poor outcome (comparing the upper and the lower third) were interleukin-6, 3.1 (95% CI: 1.9-5.0); C-reactive protein, 1.9 (95% CI: 1.2-3.1); fibrinogen, 1.5 (95% CI: 1.0-2.36); white cell count, 2.1 (95% CI: 1.3-3.4); and glucose 1.3 (95% CI: 0.8-2.1). The results for interleukin-6 were similar to other studies. However, the addition of inflammatory marker levels to validated prognostic models did not materially improve model discrimination, calibration, or reclassification for prediction of poor outcome after stroke.

CONCLUSIONS

Raised levels of markers of the acute inflammatory response after stroke are associated with poor outcomes. However, the addition of these markers to a previously validated stroke prognostic model did not improve the prediction of poor outcome. Whether inflammatory markers are useful in prediction of recurrent stroke or other vascular events is a separate question, which requires further study. Please see later in the article for the Editors' Summary.

Risk factors for epilepsy: a population-based case-control study in Kerala, southern India

We undertook a community-based case-control study on persons with active epilepsy residing in Kerala, southern India. Using a standardized questionnaire, we collected information from 362 cases and 362 controls. In the final multivariate model, family history of epilepsy (odds ratio=7.8, 95% confidence interval=3.2-18.8, P=0.000), antecedent history of febrile seizures (7.7, 4.3-14.0, 0.000), birth by complicated delivery (6.8, 2.1-21.8, 0.001), and neonatal seizures (7.8, 1.7-35.4, 008) emerged as strong independent predictors of epilepsy, followed in decreasing order by mental retardation, prematurity, maternal age 30, perinatal distress, and incomplete immunization. There were more similarities than differences in the distribution of risk factors between generalized and localization-related epilepsy syndromes. Our findings suggest interplay between genetic and acquired factors in the pathogenesis of epilepsies, and underscore the need for improvement in obstetric and neonatal care to minimize the epilepsy burden in low-income countries.

Intravitreal bevacizumab (Avastin) for age-related macular degeneration: a critical analysis of literature

PURPOSE

The current medical environment demands that quality health care is delivered at an affordable cost through the use of objective, unbiased clinical data. This study was undertaken to review the current literature on bevacizumab for age-related macular degeneration and its value in determining best clinical practice.

METHODS

Randomised controlled trials (RCTs) and observational studies that met the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria were identified from the current literature for further analysis. Data concerning treatment dosing regimens, response to treatment, complications, and factors influencing outcome and safety were extracted and compiled into a database.

RESULTS

As of January 2009, there were 5 RCTs that compared the outcomes of bevacizumab to other treatment options and 50 studies that met the STROBE criteria with similar visual and anatomical outcomes between RCTs and observational studies. Although the doses and dosing frequencies varied between the studies, the mean gain in vision at 3 months was +7.76+/-5.4 ETDRS letters (range +2 to +14.4); an effect that was maintained at 6 months in studies with longer follow-up. Predominantly classic lesions were the most responsive of all lesion subtypes. The complication profiles/rates were similar to those reported with other anti-vascular endothelial agents.

CONCLUSIONS

There is sufficient scientific and statistical evidence to advocate the effective use of OCT-guided administration of intravitreal bevacizumab for neovascular AMD. This is reflected in our study outcome measures that are comparable to findings published from recent well-conducted RCTs on intravitreal ranibizumab at the same time point.

Risk of urinary incontinence symptoms in oral contraceptive users: a national cohort study from the Swedish Twin Register

OBJECTIVE

To assess the impact of oral contraceptives on lower urinary tract dysfunction in premenopausal women.

DESIGN

Nationwide cohort study.

SETTING

National registry.

PATIENT(S)

A total of 10,791 women (born 1959-1985) from the population- based Swedish Twin Registry who participated in a web-based survey of common diseases.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Symptoms of urinary incontinence.

RESULT(S)

For users of oral contraception there was a significantly reduced risk for symptoms of stress urinary incontinence, mixed urinary incontinence, and urgency urinary incontinence. The reduction remained significant when adjusting for age, body mass index, and pregnancy history. A reduced prevalence of symptoms of overactive bladder in oral contraceptive users was also observed although the association was nonsignificant. There were no significant associations between lower urinary tract symptoms and women using a levonorgestrel-releasing intrauterine device compared with noncontraceptive users, with the exception of nocturia.

CONCLUSION(S)

Oral contraceptive use reduces the overall risk for symptoms of urinary incontinence.

Quasi-experimental evaluation without regression analysis

Evaluators of public health programs in field settings cannot always randomize subjects into experimental or control groups. By default, they may choose to employ the weakest study design available: the pretest, posttest approach without a comparison group. This essay argues that natural experiments involving comparison groups are within reach of public health program managers. Methods for analyzing natural experiments are discussed.

Meta-analysis of adverse cardiovascular outcomes associated with antecedent hypertension after myocardial infarction

The aim of this study was to investigate the association of antecedent hypertension with adverse cardiovascular outcomes after myocardial infarction. A search of Medline and EMBASE was supplemented by manual searches of the bibliographies of key retrieved reports. The studies were included if they reported antecedent hypertension as a risk factor for adverse outcomes (death, stroke, congestive heart failure, recurrent myocardial infarction) in survivors of myocardial infarctions. Relative risks (RRs) were pooled using a random-effects model, and the robustness of the pooled RRs was evaluated in sensitivity analyses. Cumulative meta-analysis, by chronologic year of study beginning, was also performed. The search yielded 17 studies (n = 56,748 participants) that reported antecedent hypertension with adverse outcomes for survivors of myocardial infarctions. Randomized clinical trials (n = 8) were pooled separately from cohort studies (n = 9). For randomized clinical trials, the pooled RRs were 1.19 (95% confidence interval [CI] 1.13 to 1.26) for all-cause mortality and 1.29 (95% CI 1.09 to 1.53) for cardiovascular disease mortality. For cohort studies, the pooled RRs were 1.46 (95% CI 1.34 to 1.61) for all-cause mortality and 1.54 (95% CI 1.22 to 1.93) for cardiovascular disease mortality. Antecedent hypertension was also consistently associated with an increased risk for stroke, congestive heart failure, and recurrent myocardial infarction. Pooled estimates were robust in sensitivity analysis. In conclusion, antecedent hypertension was associated with adverse outcomes for survivors of myocardial infarctions, the association of antecedent hypertension with all-cause mortality outcomes decreased over time, and this decreased association reflects improved treatment and management of hypertension in more recent years.

Evaluation of a strategy to improve undergraduate experience in obstetrics and gynaecology

CONTEXT

Poor interprofessional relationships in maternity units have resulted in a number of suboptimal outcomes: students are reluctant to pursue careers in obstetrics and gynaecology (O & G); trainees feel bullied, and poor communication between professionals results in avoidable adverse events. Interprofessional learning has been advocated to improve interprofessional relationships, but recent interventions have not been successful at undergraduate level. This study aimed to address this issue locally and then to disseminate our lessons, successes and challenges.

METHODS

A strategy for interprofessional team-working was developed in a large maternity unit in the UK, with a variety of interprofessional interventions spanning the attachment and opportunities to participate in specific task or research teams. These interventions were evaluated before the strategy proceeded to large-scale implementation, with a validated attitudes questionnaire (Pollard) and a reaction survey.

RESULTS

Interprofessional relationships improved significantly (P < 0.05) after the O&G attachment. There was also some improvement of borderline significance (P = 0.05) in interprofessional teamwork and communication, as well as a non-significant improvement in perceptions of interprofessional interactions. Most (17/27, 63%) students stated that O&G was their primary career intention after the attachment. They did not witness any bullying or interprofessional difficulties.

CONCLUSIONS

Contrary to findings in other studies, in which initial idealism has been reported to have collapsed after working with students from other professions, we achieved a positive reaction to the O&G attachment, harnessing students' initial positivity towards interprofessional learning and cementing it into real optimism. Our promising initial results suggest that more work is needed to further increase the impact of such strategies and to determine whether the improvements in attitudes translate to improved clinical behaviour and thence patient outcomes.

Resource use associated with type 2 diabetes in Asia, Latin America, the Middle East and Africa: results from the International Diabetes Management Practices Study (IDMPS)

AIMS

To estimate diabetes-related resource use and investigate its predictors among individuals with type 2 diabetes in 24 countries in Asia, Latin America, the Middle East and Africa.

METHODS

Cross-sectional observational data on diabetes-related resource use were collected from 15,016 individuals with type 2 diabetes within the second wave of International Diabetes Management Practices Study. Mean (SD) annual quantities were determined and predictors of diabetes-related hospitalisations, inpatient days, emergency room visits and absenteeism were investigated using negative binomial regression.

RESULTS

Patients in Asia (n = 4678), Latin America (n = 6090) and the Middle East and Africa (n = 4248) made a mean (SD) of 3.4 (6.9), 5.4 (6.7) and 2.5 (4.4) General Practitioner visits per year. The mean (SD) number of inpatient days amounted to 3.8 (18.1), 2.2 (13.9) and 2.6 (13.5) per year. Results of the regression analysis showed the major influence of diabetes-related complications and inadequate glycaemic control on resource use. The expected annual rate of hospitalisation of patients with macrovascular complications compared with those without was 4.7 times greater in Asia [incidence rate ratio (IRR) = 4.7, 95% CI: 2.8-7.8, n = 2551], 5.4 times greater in Latin America (IRR = 5.4, 95% CI: 3.0-9.8, n = 3228) and 4.4 times greater in the Middle East and Africa (IRR = 4.4, 95% CI: 2.8-6.9, n = 2630).

CONCLUSIONS

Micro- and macrovascular complications and inadequate glycaemic control are significant predictors of resource use in people with type 2 diabetes of developing countries. This knowledge confirms the health economic importance of early diagnosis of diabetes, education of patients and glycaemic control.

The effect on cardiovascular risk factors of migration from rural to urban areas in Peru: PERU MIGRANT Study

BACKGROUND

Mass-migration observed in Peru from the 1970s occurred because of the need to escape from politically motivated violence and work related reasons. The majority of the migrant population, mostly Andean peasants from the mountainous areas, tends to settle in clusters in certain parts of the capital and their rural environment could not be more different than the urban one. Because the key driver for migration was not the usual economic and work-related reasons, the selection effects whereby migrants differ from non-migrants are likely to be less prominent in Peru. Thus the Peruvian context offers a unique opportunity to test the effects of migration.

METHODS/DESIGN

The PERU MIGRANT (PEru's Rural to Urban MIGRANTs) study was designed to investigate the magnitude of differences between rural-to-urban migrant and non-migrant groups in specific CVD risk factors. For this, three groups were selected: Rural, people who have always have lived in a rural environment; Rural-urban, people who migrated from rural to urban areas; and, Urban, people who have always lived in a urban environment.

DISCUSSION

Overall response rate at enrolment was 73.2% and overall response rate at completion of the study was 61.6%. A rejection form was obtained in 282/323 people who refused to take part in the study (87.3%). Refusals did not differ by sex in rural and migrant groups, but 70% of refusals in the urban group were males. In terms of age, most refusals were observed in the oldest age-group (>60 years old) in all study groups. The final total sample size achieved was 98.9% of the target sample size (989/1000). Of these, 52.8% (522/989) were females. Final size of the rural, migrant and urban study groups were 201, 589 and 199 urban people, respectively. Migrant's average age at first migration and years lived in an urban environment were 14.4 years (IQR 10-17) and 32 years (IQR 25-39), respectively. This paper describes the PERU MIGRANT study design together with a critical analysis of the potential for bias and confounding in migrant studies, and strategies for reducing these problems. A discussion of the potential advantages provided by the case of migration in Peru to the field of migration and health is also presented.

EACTS/ESCVS best practice guidelines for reporting treatment results in the thoracic aorta

Endovascular treatment of the thoracic aorta (TEVAR) is rapidly expanding, with new devices and techniques, combined with classical surgical approaches in hybrid procedures. The present guidelines provide a standard format for reporting results of treatment in the thoracic aorta, and to facilitate analysis of clinical results in various therapeutic approaches. These guidelines specify the essential information and definitions, which should be provided in each article about TEVAR: It is hoped that strict adherence to these criteria will make the future publications about TEVAR more comparable, and will enable the readership to draw their own, scientifically validated conclusions about the reports.

Retrospective cohort study of diagnosis-delivery interval with umbilical cord prolapse: the effect of team training

OBJECTIVE

To determine whether the introduction of multi-professional simulation training was associated with improvements in the management of cord prolapse, in particular, the diagnosis-delivery interval (DDI).

DESIGN

Retrospective cohort study.

SETTING

Large tertiary maternity unit within a University Hospital in the United Kingdom.

SAMPLE

All cases of cord prolapse with informative case record: 34 pre-training, 28 post-training.

METHODS

Review of hospital notes and software system entries; comparison of quality of management for umbilical cord prolapse pre-training (1993-99) and post-training (2001-07).

MAIN OUTCOME MEASURES

Diagnosis-delivery interval; proportion of caesarean section (CS) in whom actions were taken to reduce cord compression; type of anaesthesia for CS births; rate of low (<7) 5-minute Apgar scores; rate of admission to neonatal intensive care unit (NICU) (if birthweight >2500 g).

RESULTS

After training, there was a statistically significant reduction in median DDI from 25 to 14.5 minutes (P < 0.001). Post-training, there was also a statistically significant increase in the proportion of CS where recommended actions had been performed (from 34.78 to 82.35%, P = 0.003). There was a nonsignificant increase in the use of spinal anaesthesia for CS, from 8.70 to 17.65%, and a nonsignificant reduction in the rate of low Apgar scores from 6.45 to 0% and in the rate of admission to NICU from 38.46 to 22.22%.

CONCLUSIONS

The introduction of annual training, in accordance with national recommendations, was associated with improved management of cord prolapse. Future studies could assess whether this improved management translates into better outcomes for babies and their mothers.

Systematic review on drug and diet-induced endoscopic remission in Crohn's disease

BACKGROUND

Neither the rate of endoscopic remission (ER) in Crohn's disease (CD) after therapy nor its role in patients' prognosis is well defined.

AIM

To systematically review the current evidence on the proportion of ER of different therapies in patients with Crohn's disease and its relation with clinical outcomes.

METHODS

Databases (MEDLINE and Cochrane) and manual search of manuscripts found 482 titles. Data was extracted from 24 manuscripts.

RESULTS

Ten different methods were used to assess endoscopic outcomes. Corticosteroids induced a pooled proportion of patients with no ulcerations at endoscopic follow-up of 17% (95% confidence interval: 12-22%) lower than that found with infliximab [44% (34-53%)], diet [43% (33-52%)] or azathioprine [54% (38-69%)] (P<0.0001). Enteric diets and infliximab were associated with 61% (52-70%) and 70% (62-78%) reduction in endoscopic scores, respectively, significantly higher than corticosteroids [45% (39-52%)] (P=0.01) and placebo [12% (1-22%)] (P<0.0001). A linear relation between ER and clinical remission was observed with infliximab (r=0.931). Only one study tried to assess the direct correlation between ER and patients' prognosis.

CONCLUSION

Available treatments induce significant endoscopic improvement. However, pooled results should be cautiously interpreted because of the diversity of measurements. A better definition of endoscopic outcomes and a prospective validation of their relevance in patients with Crohn's disease are needed.

How to design a good case series

A case series is a descriptive study that follows a group of patients who have a similar diagnosis or who are undergoing the same procedure over a certain period of time. As there is no experimental protocol or control for allocation of patients to treatment, surgeons and patients decide on whether or not treatment is given, making the clinical sample representative of a common clinical population. Results of case series can generate hypotheses that are useful in designing further studies, including randomized controlled trials. However, no causal inferences should be made from case series regarding the efficacy of the investigated treatment. This article will provide principles for the design, analysis, and reporting of case series, illustrated by examples from the orthopaedic surgical literature.

Obesity and mammography: a systematic review and meta-analysis

BACKGROUND

Obese women experience higher postmenopausal breast cancer risk, morbidity, and mortality and may be less likely to undergo mammography.

OBJECTIVES

To quantify the relationship between body weight and mammography in white and black women.

DATA SOURCES AND REVIEW METHODS

We identified original articles evaluating the relationship between weight and mammography in the United States through electronic and manual searching using terms for breast cancer screening, breast cancer, and body weight. We excluded studies in special populations (e.g., HIV-positive patients) or not written in English. Citations and abstracts were reviewed independently. We abstracted data sequentially and quality information independently.

RESULTS

Of 5,047 citations, we included 17 studies in our systematic review. Sixteen studies used self-reported body mass index (BMI) and excluded women <40 years of age. Using random-effects models for the six nationally representative studies using standard BMI categories, the combined odds ratios (95% CI) for mammography in the past 2 years were 1.01 (0.95 to 1.08), 0.93 (0.83 to 1.05), 0.90 (0.78 to 1.04), and 0.79 (0.68 to 0.92) for overweight (25-29.9 kg/m(2)), class I (30-34.9 kg/m(2)), class II (35-39.9 kg/m(2)), and class III (> or =40 kg/m(2)) obese women, respectively, compared to normal-weight women. Results were consistent when all available studies were included. The inverse association was found in white, but not black, women in the three studies with results stratified by race.

CONCLUSIONS

Morbidly obese women are significantly less likely to report recent mammography. This relationship appears stronger in white women. Lower screening rates may partly explain the higher breast cancer mortality in morbidly obese women.

Improving the reporting of clinical research

A demand for transparency