Evaluation of medical and health economic effectiveness of bariatric surgery (obesity surgery) versus conservative strategies in adult patients with morbid obesity

Background: Obesity with its associated medical, psychological, social, and economic complications is considered a chronic, multifactorial disorder. Given the magnitude of the challenge obesity, there is a clear need for preventive as well as therapeutic measures and strategies on an individual and a public health level. Objectives: The goal of this health technology assessment (HTA)-report is to summarise the current literature on bariatric surgery, to evaluate their medical effectiveness/efficacy and cost-effectiveness as well as the ethical, social and legal implications of these procedures in comparison to conventional therapies and compared to each other. Methods: Relevant publications are identified by means of a structured search of databases accessed on 13.11.2006 and an update conducted on 12.11.2007. In addition, a manual search of identified reference lists is conducted. The present report includes German and English literature published since 2001 and targeting adult subjects with morbid obesity (body mass index (BMI) >=40 kg/m² or BMI >=35 kg/m² with severe comorbidities). The methodological quality of studies included is assessed according to pre-defined quality criteria by two independent scientists. Results: Among 5910 retrieved publications, 25 medical articles, as well as seven health economic studies meet the inclusion criteria. The medical studies show a superior weight loss following bariatric surgery compared to conventional therapy. Malabsorptive procedures lead to a more profound weight loss than purely restrictive procedures. Weight reduction in general is accompanied by a reduced frequency of comorbidities (mostly diabetes type 2). The evidence is not sufficient to quantify these effects for individual procedures or to assess long-term outcomes. However, recent studies show a profound survival benefit for surgically treated patients up to a period of eleven years. The economic studies illustrate that bariatric surgery is cost-effective compared to no treatment or conservative treatment. The comparison between surgical therapies does not allow to draw any conclusions on cost-effectiveness. Appropriate studies/surveys, which are concerned with ethical, legal and social aspects, are not available. Discussion: Concerning clinical outcomes as well as cost-effectiveness, there is a lack of high quality studies. Clinical effectiveness and safety as well as cost-effectiveness of bariatric procedures in the short- and medium-term course are agreed on, but long-term evaluations that focus not exclusively on weight loss, but also on comorbidities and patient relevant outcomes such as quality of life, are needed. Also within the economic views are missing long-term evaluation particularly for the German health care system. Conclusion: Based upon the available literature the short- and medium-term effectiveness of bariatric procedures on weight loss, comorbidities, e. g. diabetes, and mortality can be assumed and also seems to be cost-effective. No recommendation can be given with respect to the choice of a certain bariatric procedure or to the selection of particular groups of patients

Medical and health economic assessment of radiosurgery for the treatment of brain metastasis

Background: Radiotherapy for patients suffering from malignant neoplasms has developed greatly during the past decades. Stereotactic radiosurgery (SRS) is one important radiotherapeutic option which is defined by a single and highly focussed application of radiation during a specified time interval. One of its important indications is the treatment of brain metastases. Objectives: The objective of this HTA is to summarise the current literature concerning the treatment of brain metastasis and to compare SRS as a single or additional treatment option to alternative treatment options with regard to their medical effectiveness/efficacy, safety and cost-effectiveness as well as their ethical, social and legal implications. Methods: A structured search and hand search of identified literature are performed from January 2002 through August 2007 to identify relevant publications published in English or German. Studies targeting patients with single or multiple brain metastases are included. The methodological quality of included studies is assessed according to quality criteria, based on the criteria of evidence based medicine. Results: Of 1,495 publications 15 medical studies meet the inclusion criteria. Overall study quality is limited and with the exception of two randomized controlleed trials (RCT) and two meta-analyses only historical cohort studies are identified. Reported outcome measures are highly variable between studies. Studies with high methodological quality provide evidence, that whole-brain radiotherapy (WBRT) in addition to SRS and SRS in addition to WBRT is associated with improved local tumour control rates and neurological function. However, only in patients with single brain metastasis, RPA-class 1 (RPA = Recursive partitioning analysis) and certain primary tumour entities, this combination of SRS and WBRT is associated with superior survival compared to WBRT alone. Studies report no significant differences in adverse events between treatment groups. Methodologically less rigorous studies provide no conclusive evidence with regard to medical effectiveness and safety, comparing SRS to WBRT, neurosurgery (NS) or hypofractionated radiotherapy (HCSRT). The quality of life is not investigated in any of the studies. Within the searched databases a total of 320 economic publications are identified. Five publications are eligible for this report. The five reports have a quiet variable quality. Concerning the economic efficiency of alternative equipment, while assuming equal effectiveness, the calculations show, that economic efficiency depends to a large extend on the number of patients treated. In case the two alternative equipments are used solely for SRS, the Gamma Knife might be more cost-efficient. Otherwise an adapted linear accelerator is most likely to be beneficial because of its flexibility. One Health Technology Assessment (HTA) states, that the cost for a Gamma Knife and a dedicated linear accelerator are comparable, while an adapted version is cheaper. No reports concerning ethical, legal and social aspects are identified. Discussion: Overall, quantity and quality of identified studies is limited. However, the identified studies indicate that the prognosis of patients with brain metastases is despite highly developed and modern treatment regimes still limited. Conclusive evidence with regard to the effectiveness of identified interventions is only available for the combined treatment of SRS and WBRT compared to SRS or WBRT alone. Furthermore, there is insufficient evidence to compare SRS with WBRT, NS or HCSRT. The efficiency of the different equipments depends to a great extent on the number and the indications of the patients treated. If dedicated systems are used to their full capacity, there is some evidence for superior cost-effectiveness. If more treatment flexibility is required, adapted systems seem to be advantageous. However, equal treatment effectiveness is a necessary assumption for these conclusions. The need for a treatment precision can influence the purchase decision. No reports concerning more recent therapeutic alternatives are currently available. Conclusion: Combination of SRS and WBRT is associated with improved local tumour control and neurological function compared to SRS or WBRT alone. However, only for patients with single metastasis there is strong evidence that this results in improved survival compared to WBRT alone. Methodologically rigorous studies are warranted to investigate SRS compared to WBRT and NS and to investigate the quality of life in patients undergoing these treatment regimes.Concerning the type of equipment used, economic efficiency depends to a great extend on the capacity at which the system can be used. Dedicated systems might be favourable for a high number of patients, while lower patient counts probably favour adapted systems with their superior treatment flexibility. Using the equipment at its full capacity may result in a limited number of machines, what in turn may give rise to the question of an equal and easy access to this technology. Studies focusing on the comparative effectiveness and cost-effectiveness of different treatment options and their combinations, especially for the German setting, are warranted

MRI plaque imaging reveals high-risk carotid plaques especially in diabetic patients irrespective of the degree of stenosis

<p>Abstract</p> <p>Background</p> <p>Plaque imaging based on magnetic resonance imaging (MRI) represents a new modality for risk assessment in atherosclerosis. It allows classification of carotid plaques in high-risk and low-risk lesion types (I-VIII). Type 2 diabetes mellitus (DM 2) represents a known risk factor for atherosclerosis, but its specific influence on plaque vulnerability is not fully understood. This study investigates whether MRI-plaque imaging can reveal differences in carotid plaque features of diabetic patients compared to nondiabetics.</p> <p>Methods</p> <p>191 patients with moderate to high-grade carotid artery stenosis were enrolled after written informed consent was obtained. Each patient underwent MRI-plaque imaging using a 1.5-T scanner with phased-array carotid coils. The carotid plaques were classified as lesion types I-VIII according to the MRI-modified AHA criteria. For 36 patients histology data was available.</p> <p>Results</p> <p>Eleven patients were excluded because of insufficient MR-image quality. DM 2 was diagnosed in 51 patients (28.3%). Concordance between histology and MRI-classification was 91.7% (33/36) and showed a Cohen's kappa value of 0.81 with a 95% CI of 0.98-1.15. MRI-defined high-risk lesion types were overrepresented in diabetic patients (n = 29; 56.8%). Multiple logistic regression analysis revealed association between DM 2 and MRI-defined high-risk lesion types (OR 2.59; 95% CI [1.15-5.81]), independent of the degree of stenosis.</p> <p>Conclusion</p> <p>DM 2 seems to represent a predictor for the development of vulnerable carotid plaques irrespective of the degree of stenosis and other risk factors. MRI-plaque imaging represents a new tool for risk stratification of diabetic patients.</p> <p>See Commentary: <url>http://www.biomedcentral.com/1741-7015/8/78/abstract</url></p

Prognostic value of the ABCD2 score beyond short-term follow-up after transient ischemic attack (TIA) - a cohort study

<p>Abstract</p> <p>Background</p> <p>Transient ischemic attack (TIA) patients are at a high vascular risk. Recently the ABCD²score was validated for evaluating short-term stroke risk after TIA. We assessed the value of this score to predict the vascular outcome after TIA during medium- to long-term follow-up.</p> <p>Methods</p> <p>The ABCD²score of 176 TIA patients consecutively admitted to the Stroke Unit was retrospectively calculated and stratified into three categories. TIA was defined as an acute transient focal neurological deficit caused by vascular disease and being completely reversible within 24 hours. All patients had to undergo cerebral MRI within 5 days after onset of symptoms as well as extracranial and transcranial Doppler and duplex ultrasonography. At a median follow-up of 27 months, new vascular events were recorded. Multivariate Cox regression adjusted for EDC findings and heart failure was performed for the combined endpoint of cerebral ischemic events, cardiac ischemic events and death of vascular or unknown cause.</p> <p>Results</p> <p>Fifty-five patients (32.0%) had an ABCD²score ≤ 3, 80 patients (46.5%) had an ABCD2 score of 4-5 points and 37 patients (21.5%) had an ABCD²score of 6-7 points. Follow-up data were available in 173 (98.3%) patients. Twenty-two patients (13.8%) experienced an ischemic stroke or TIA; 5 (3.0%) a myocardial infarction or acute coronary syndrome; 10 (5.7%) died of vascular or unknown cause; and 5 (3.0%) patients underwent arterial revascularization. An ABCD²score > 3 was significantly associated with the combined endpoint of cerebral or cardiovascular ischemic events, and death of vascular or unknown cause (hazard ratio (HR) 4.01, 95% confidence interval (CI) 1.21 to 13.27). After adjustment for extracranial ultrasonographic findings and heart failure, there was still a strong trend (HR 3.13, 95% CI 0.94 to 10.49). Whereas new cardiovascular ischemic events occurred in 9 (8.3%) patients with an ABCD²score > 3, this happened in none of the 53 patients with a score ≤ 3.</p> <p>Conclusions</p> <p>An ABCD²score > 3 is associated with an increased general risk for vascular events in the medium- to long-term follow-up after TIA.</p

Educational intervention to improve physician reporting of adverse drug reactions (ADRs) in a primary care setting in complementary and alternative medicine

<p>Abstract</p> <p>Background</p> <p>Recent studies have shown that adverse drug reactions (ADRs) are underreported. This may be particularly true of ADRs associated with complementary and alternative medicine (CAM). Data on CAM-related ADRs, however, are sparse.</p> <p>Objective was to evaluate the impact of an educational intervention and monitoring programme designed to improve physician reporting of ADRs in a primary care setting.</p> <p>Methods</p> <p>A prospective multicentre study with 38 primary care practitioners specialized in CAM was conducted from January 2004 through June 2007. After 21 month all physicians received an educational intervention in terms of face-to-face training to assist them in classifying and reporting ADRs. The study centre monitored the quantity and quality of ADR reports and analysed the results.</p> <p>To measure changes in the ADR reporting rate, the median number of ADR reports and interquartile range (IQR) were calculated before and after the educational intervention. The pre-intervention and post-intervention quality of the reports was assessed in terms of changes in the completeness of data provided for obligatory items. Interrater reliability between the physicians and the study centre was calculated using Cohen's kappa with a 95% confidence interval (CI). We used Mann Whitney U-test for testing continuous data and chi-square test was used for categorical data. The level of statistical significance was set at <it>P </it>< 0.05.</p> <p>Results</p> <p>A total of 404 ADRs were reported during the complete study period. An initial 148% increase (<it>P </it>= 0.001) in the number of ADR reports was observed after the educational intervention. Compared to baseline the postinterventional number of ADR reportings was statistically significant higher (P < 0.005) through the first 16 months after the intervention but not significant in the last 4-month period (median: 8.00 (IQR [2.75; 8.75]; P = 0.605). The completeness of the ADR reports increased from 80.3% before to 90.7% after the intervention. The completeness of the item for classifying ADRs as serious or non-serious increased significantly (<it>P </it>< 0.001) after the educational intervention. The quality of ADR reports increased from kappa 0.15 (95% CI: 0.08; 0.29) before to 0.43 (95% CI: 0.23; 0.63) after the intervention.</p> <p>Conclusion</p> <p>The results of the present study demonstrate that an educational intervention can increase physician awareness of ADRs. Participating physicians were able to incorporate the knowledge they had gained from face-to-face training into their daily clinical practice. However, the effects of the intervention were temporary.</p

Lack of association between right-to-left shunt and cerebral ischemia after adjustment for gender and age

<p>Abstract</p> <p>Introduction</p> <p>A number of studies has addressed the possible association between patent foramen ovale (PFO) and stroke. However, the role of PFO in the pathogenesis of cerebral ischemia has remained controversial and most studies did not analyze patient subgroups stratified for gender, age and origin of stroke.</p> <p>Methods</p> <p>To address the role of PFO for the occurrence of cerebral ischemia, we investigated the prevalence of right-to-left shunt in a large group of patients with acute stroke or TIA. 763 consecutive patients admitted to our hospital with cerebral ischemia were analyzed. All patients were screened for the presence of PFO by contrast-enhanced transcranial Doppler sonography at rest and during Valsalva maneuver. Subgroup analyses were performed in patients stratified for gender, age and origin of stroke.</p> <p>Results</p> <p>A right-to-left shunt was detected in 140 (28%) male and in 114 (42%) female patients during Valsalva maneuver, and in 66 (13%) and 44 (16%) at rest respectively. Patients with right-to-left shunt were younger than those without (<it>P </it>< 0.001). PFO was associated with stroke of unknown origin in male (<it>P </it>= 0.001) but not female patients (<it>P </it>> 0.05). After adjusting for age no significant association between PFO and stroke of unknown origin was found in either group.</p> <p>Conclusion</p> <p>Our findings argue against paradoxical embolization as a major cause of cerebral ischemia in patients with right-to-left shunt. Our data demonstrate substantial gender-and age-related differences that should be taken into account in future studies.</p

Transcranial Doppler ultrasonography predicts cardiovascular events after TIA

<p>Abstract</p> <p>Background</p> <p>Transient ischemic attack (TIA) patients are at high vascular risk. We assessed the value of extracranial (ECD) and transcranial (TCD) Doppler and duplex ultrasonography to predict clinical outcome after TIA.</p> <p>Methods</p> <p>176 consecutive TIA patients admitted to the Stroke Unit were recruited in the study. All patients received diffusion-weighted imaging, standardized ECD and TCD. At a median follow-up of 27 months, new vascular events were recorded.</p> <p>Results</p> <p>22 (13.8%) patients experienced an ischemic stroke or TIA, 5 (3.1%) a myocardial infarction or acute coronary syndrome, and 5 (3.1%) underwent arterial revascularization. ECD revealed extracranial ≥ 50% stenosis or occlusions in 34 (19.3%) patients, TCD showed intracranial stenosis in 15 (9.2%) and collateral flow patterns due to extracranial stenosis in 5 (3.1%) cases. Multivariate analysis identified these abnormal ECD and TCD findings as predictors of new cerebral ischemic events (ECD: hazard ratio (HR) 4.30, 95% confidence interval (CI) 1.75 to 10.57, P = 0.01; TCD: HR 4.73, 95% CI 1.86 to 12.04, P = 0.01). Abnormal TCD findings were also predictive of cardiovascular ischemic events (HR 18.51, 95% CI 3.49 to 98.24, P = 0.001).</p> <p>Conclusion</p> <p>TIA patients with abnormal TCD findings are at high risk to develop further cerebral and cardiovascular ischemic events.</p