Impact of laparoscopic adjustable gastric banding on plasma ghrelin, eating behaviour and body weight

BACKGROUND

Plasma ghrelin, an orexigenic peptide derived from the stomach and duodenum, increases following weight loss and might contribute to weight regain. The aim of the present study was to evaluate the effect of laparoscopic adjustable gastric banding (LAGB) on body weight and body composition as well as plasma ghrelin in relation to eating behaviour in morbidly obese patients.

MATERIALS AND METHODS

This study was performed in 23 morbidly obese subjects who underwent standardized LAGB. Fasting plasma ghrelin was measured before and 6 months after surgery and was correlated with body weight, body composition, and eating behaviour.

RESULTS

Six months after LAGB, body weight decreased significantly by -15.7 +/- 1.4 kg (mean +/- SEM, P = 0.0001) which was accompanied by an increased cognitive restraint of eating (P = 0.001), and by a decreased disinhibition of eating and susceptibility to hunger (P = 0.0001). Plasma ghrelin increased (P = 0.016) by 27.2% from 100.39 +/- 12.90 to 127.22 +/- 13.15 fmol mL(-1). The change in plasma ghrelin correlated with changes in body weight (r = -0.49, P = 0.02), BMI (r = -0.42, P = 0.048) and fat mass (r = -0.519, P = 0.013), but not with changes of fat-free mass and of the three dimensions of eating behaviour.

CONCLUSION

Weight loss following LAGB leads to an increase in fasting plasma ghrelin and is accompanied by a decrease in hunger, disinhibition of eating and an increase in cognitive restraint. Thus, changes in eating behaviour, which promote reduction of food intake and not fasting ghrelin, determines weight loss achieved by LAGB.

Zur Problematik von Akupunkturstudien am Beispiel der Methodik von gerac

OBJECTIVE

Conflicting or ambivalent findings on the effectiveness of body acupuncture in pain treatment are often attributed to flaws in study methodology. The paper describes the methodology used for the German Acupuncture Trials (gerac), which demonstrates that it is possible to design acupuncture studies in accordance with the standards of good clinical practice.

METHOD

Approximately 1000 chronic pain sufferers per indication (migraine, tension-type headache, low back pain (cLBP), or gonarthrosis) are randomly allocated to one of three treatment groups (verum acupuncture, sham acupuncture, or established conservative therapy). Patients are blind to the type of acupuncture. All patients receive ten sessions of treatment (two per week) with an option of adding five more treatments in cases of slight but insufficient improvement (number of headache days or von Korff pain score). Participating physicians are in private practice, representing a variety of specialties. All have completed at least a 140-hour training course in acupuncture. Mandatory and optional verum and sham points are predefined. The point selection is individualized according to the criteria of traditional Chinese medicine (TCM). Primary outcome measures are number of headache days per month, von Korff Graded Chronic Pain Scale or Hannover Functional Ability Questionnaire (cLBP), or WOMAC scores (gonarthrosis). Data are assessed by trained telephone interviewers not involved in treatment and blind to types of acupuncture.

PRESENT STATUS

Over 500 participating physicians in ten urban areas of Germany. Patient recruitment for cLBP and gonarthrosis was completed in November 2003 and March 2004 respectively. Recruitment for chronic headaches will be completed in autumn 2004.

CONCLUSIONS

The gerac trials prove that it is possible to design and carry out acupuncture studies in accordance to stringent standards of methodology and clinical practice. The results will form a basis for the assessment of acupuncture effectiveness in Germany and abroad.

[Visual cortex in the Tolosa-Hunt syndrome. Functional imaging for the detection of a psychogenic disorder--a case report]

Besides painful ophthalmoplegia, patients suffering from Tolosa-Hunt syndrome often present increasing loss of visual perception. The impairment of the optic nerve leads to a delay of the VEP (visual evoked potentials) responses. Using the method of magnetic resonance imaging (MRI), some patients present unspecific alterations in the vicinity of the optic nerve. However, both methods (VEP and MRI) are unsuitable to assess the effect of an impaired optic nerve function on neuronal processing in the visual cortex. We report one patient suffering from Tolosa-Hunt syndrome affecting the optic nerve. We used fMRI (functional magnetic resonance imaging) to show how this impairment of the optic nerve alters cortical processing of visual information. The activity of the unaffected visual cortex was bilaterally reduced when compared to healthy volunteers but greater that obtained from patients suffering from bilateral occipital infarction. Our results offer new opportunities to assess the efficiency of therapy in patients with increasing loss of visual perception due to the Tolosa-Hunt syndrome. Further studies are necessary to investigate, whether fMRI also provides the possibility to assess the efficiency of drug therapy on optic nerve function.

Acute exercise has no effect on ghrelin plasma concentrations

Exercise is a potent, dose-dependent stimulus of growth hormone (GH) secretion. The hypothalamic peptides, GH-releasing hormone (GHRH) and somatostatin are regarded as major regulators of this stimulation. The role of the stomach-derived peptide ghrelin, which has been shown to exert strong GH releasing effects, has not been fully characterized yet. We therefore studied GH and ghrelin plasma concentrations in response to graded levels of exercise in eight healthy young volunteers. After determination of their individual maximal exercise capacity, all individuals underwent a treadmill exercise at 50 %, 70 %, and 90 % of maximum oxygen consumption (VO (2)max) on different days. Maximal GH response to exercise was observed after 40 minutes at 50 % VO (2)max and after 20 minutes at 70 and 90 % VO (2max). GH serum concentrations increased significantly at all three exercise intensities (GH peak concentrations were 5.8 +/- 2.3 ng/ml, 12.0 +/- 3.2 ng/ml, and 9.8 +/- 4.7 ng/ml, respectively). In contrast, ghrelin plasma concentrations remained unchanged at all three workloads. Assuming that the sensitivity of the GH neuroendocrine/metabolic regulation of GH is unaltered, ghrelin does not participate in the regulation of the GH response to exercise in healthy males.

Schmerztherapeutische Angebote an Kliniken in Deutschland

Specialised pain treatment is available at inpatient, daycare and outpatient units at hospitals in Germany. A total of 579 hospitals in Germany offer at least one of the three pain treatment options. The main treatment involves outpatient care, but inpatient wards and daycare institutions have become more common. The type and number of pain treatment facilities differ regionally. Five of the 16 counties do not officially offer inpatient care at all, although pain treatment sites have been opened on the initiative of the hospitals themselves. Since specialised pain treatment is insufficiently defined by diagnosis (ICD-10) or procedures (OPS) in the German DRG system, it is not possible to recognise its availability when the facilities are not officially named. Pain treatment should be differentiated dependent on whether patients are treated within a single area of expertise or by specialised multi-professional pain facilities. At hospitals, systematic multimodal pain treatment is possible. Inpatient and daycare pain treatment programs are suitable when outpatient treatment has failed. An overview of the pain therapies offered is a prerequisite for their optimal use, the demonstration of their necessity and for their continued development throughout Germany. This study was planned and supervised by the commission for quality assurance of the German IASP chapter and was sponsored by the German IASP chapter.

Das komplexe regionale Schmerzsyndrom

Since the term "complex regional pain syndromes" (CRPS) was introduced based on a revised taxonomy for disorders previously called reflex sympathetic dystrophy and causalgia in 1995, much knowledge grew up on the understanding and therapy of the disease. This review gives an overview on the clinical characteristics, pathophysiology, diagnostic tools and therapeutic options in CRPS. It will especially focus on recent findings on the role of the sympathetic nervous system, the central nervous system and peripheral inflammatory processes as underlying mechanisms. Although there is no diagnostic gold standard, careful clinical evaluation and additional apparative test procedures are very helpful for the diagnosis. An early and interdisciplinary approach is the basis for an optimal and successful treatment.

[Pitfalls in medical expert evaluation. Of "credible" probands and "convincing" experts]

Periodical reading of medical expert opinions reveals deficient assessment-knowledge on the part of German physicians. Six characteristic cases are presented and discussed. The instructive examples show how careless doctors risk their reputation. Inadequate expert opinions are useless. Courts cannot judge correctly, administrations cannot decide in time, insurance companies cannot regulate reasonably. Finally inferior assessments harm more than they serve--especially the doctor's reputation.

NMDA-mediated mechanisms in cortical excitability changes after limb amputation

OBJECTIVES

The aim of our study was to determine the role of N-methyl-d-aspartate (NMDA)-mediated mechanisms in cortical excitability changes after limb amputation, and their possible relationship to phantom pain.

MATERIALS AND METHODS

Sixteen upper limb amputees who were suffering from chronic phantom pain received the NMDA-antagonist memantine or placebo for 3 weeks. Intracortical inhibition (ICI) and intracortical facilitation (ICF) were determined at baseline and on day 21 using transcranial magnetic stimulation. Simultaneously, phantom pain intensity was assessed.

RESULTS

Memantine reduced ICF and enhanced ICI to roughly the same extent as seen in healthy subjects in a previous study. These changes were not correlated to the reduction of phantom pain.

CONCLUSION

We therefore conclude that NMDA-mediated mechanisms influence changes of ICI and ICF occurring after limb amputation. However, our results suggest that these cortical excitability changes and phantom pain are independent of each other.

Bilateral motor cortex disinhibition in complex regional pain syndrome (CRPS) type I of the hand

BACKGROUND

Complex regional pain syndrome type I (CRPS I) develops as a consequence of trauma affecting the limbs, without obvious nerve lesion. Its features include pain, edema, autonomic dysfunction, movement disorder, and trophic changes. CNS involvement is suggested by the symptoms, but the pathophysiology of CRPS I is unknown.

OBJECTIVE

To assess excitability changes in the motor cortex in patients with CRPS I.

METHODS

The authors studied 25 patients with unilateral CRPS I involving the hand by means of transcranial magnetic stimulation using a paired-pulse paradigm. Motor threshold (MT) and intracortical inhibition and facilitation were determined on the affected and the clinically unaffected side. A control group of 20 healthy subjects was studied.

RESULTS

The authors found a significant reduction of intracortical inhibition on both sides of patients with CRPS compared with control subjects, whereas intracortical facilitation and MT did not differ significantly. However, in the patients' group, the presence of allodynia significantly decreased MT.

CONCLUSIONS

The authors showed a bilateral disinhibition of the motor cortex in patients with complex regional pain syndrome.

[Validation of the German Mainz Pain Staging System in different pain syndromes]

OBJECTIVE

Our study was carried out to clarify whether differences in pain intensity,pain-related disability,depression and quality of life change with respect to the stage of chronicity of the Mainz Pain Staging Study (MPSS) in different pain syndromes. Keywords.

METHODS

All patients with an initial pain clinic consultation from July 2000 to July 2001 and suffering from four major pain syndromes ("headache", "neuropathic pain", "back pain" or "muscle and joint pain") were included. Indicators of validity were several self-rating scales from the German pain questionnaire of the German Chapter of the International Association for the Study of Pain (DGSS). Patient data were collected using QUAST, a database environment specifically developed for documentation and quality assurance in pain therapy. An assessment was made for each of the four major diagnoses to determine whether patients in the three chronicity stages differed in their psychometric test results. In addition,the four diagnosis groups were tested for differences from one another.

RESULTS

A total of 862 patient charts with documented pain syndromes and MPSS were extracted and analyzed. The extent of the subjective psychosocial stress and disability increased in all diagnosis groups and was correlated with the chronicity stage. The proportion of patients with an indication of clinically relevant depression (ADS score >23) increased with chronicity regardless of the pain diagnosis. The four main diagnosis groups differed with respect to the chronicity stage according to MPSS (P<0.001), with headache patients being classified predominantly as stage I. Patients with an additional pain diagnosis had a higher chronicity stage (P<0.001).

CONCLUSION

Our results underline the validity of the MPSS for the four diagnosis groups examined; however, pain diagnosis must be controlled in all studies using chronicity stage as an independent variable, e.g., therapy studies. For optimal results physicians must closely follow the test instructions of the MPSS.

[Complex regional pain syndrome. Sympathetic reflex dystrophy and causalgia]

Complex regional pain syndromes (CRPS) occur as the inadequate response to painful trauma in a distal extremity. With CRPS I (sympathetic reflex dystrophy), no lesion of the nerve is present. Aside from sensory disturbances, burning deep spontaneous pain and mechanical allodynia are characteristic. Disturbances in the skin blood circulation,sweating,edema,and trophic disturbances of the skin, joints, and bones are typical. Reduction in muscle strength, tremor, and late dystonic changes comprise the motor disturbances. All symptoms are distributed in the distal extremity and not limited to the region of the peripheral nerves. Complex regional pain syndrome II (causalgia),develops following a partial peripheral nerve lesion. The distally generalized symptoms are identical. Successful therapy depends on an early start of interdisciplinary treatment. In addition to the pain therapy,physiotherapy plays a decisive role in rehabilitation. During the acute phase, freedom from pain at rest and retrogression of the edema must be achieved. With slight spontaneous pain, a conservative therapeutic method may be applied (analgesics, rest, raised position). In case of insufficient improvement and in difficult cases, the effect of intervention (sympathetic blockade) should be tested and possibly a blockade series performed. After reduced spontaneous pain,physiotherapy should be increased stepwise.

[Computer-assisted system for analysis of heart rate variability in clinical studies]

This paper describes an adaptable framework that facilitates exploratory analysis, interpretation and classification of beat-to-beat data extracted from the electrocardiogram (ECG). The system supports a variety of user-defined annotations and allows the definition of analysis programs. Special care is taken on the correct treatment of corrupted and missing data, ubiquitously found in real world problems. Besides the computation, the performance of single features can be inspected using different kinds of diagrams provided by the system. Combinations of features can be evaluated using a polynomial classifier. Both the computation and combination of features are defined as tasks that can be dispatched by a server to various clients. The framework is easily adaptable to different problem structures and has been used successfully in three studies.

[Preventing prostate carcinoma in men with familial disposition]

A family history is one of the strongest risk factors for prostate cancer (PC). We evaluated the detection rate of PC in relatives of 119 German PC families that took part in ongoing linkage analyses. Brothers of patients with sporadic prostate cancer aged < 55 years at onset were included as well. Responses were received from 120/196 (61.2%) individuals of the familial and 67/120 (55.8%) of the sporadic group. Findings (DRE, TRUS, PSA) were more often suspicious for carcinoma in the PC families. Prostate cancer was diagnosed in 6 (5.0%) and 2 (2.99%) participants of the familial and the sporadic group, respectively. These detection rates tended to be higher than that of an age-matched subgroup of an unselected population in other European screening studies. The most important risk factor for the diagnosis of PC was a low average age at onset within the family. These data imply that prostate cancer screening in the high-risk group of men with familial predisposition cannot be assessed by population-based studies and should be evaluated separately.

A candidate gene approach within the susceptibility region PCaP on 1q42.2-43 excludes deleterious mutations of the PCTA-1 gene to be responsible for hereditary prostate cancer

OBJECTIVE

The Prostate Carcinoma Tumor Antigen-1 (PCTA-1) is located at the prostate cancer susceptibility locus on chromosome 1q42.2-43 (PCaP). In this candidate gene approach, we searched for deleterious mutations within the PCTA-1 gene and its promoter.

MATERIALS AND METHODS

Seventy-seven familial prostate cancer cases from 36 German and French pedigrees were screened for germline mutations in the PCTA-1 gene using enzymatic mutation detection (EMD). Putative missense mutations were genotyped by RPLP and ddNTP primer extension assays in 88 controls to assess allele frequencies and haplotypes.

RESULTS

Several sequence variants were found but none of the findings indicated a deleterious mutation. Three affected brothers showed an intronic variation, which may interfere with correct splicing. Four non-conservative SNPs were characterized, coding for the amino acid alterations Y19F, C36R, V56M and S184R. All exchanges were found in controls with common allelic frequencies of at least 28%. Haplotype definition including six SNPs within the PCTA-1 gene revealed a complete linkage disequilibrium. Low haplotype diversity leads to a predominance of only two peptide variants of the PCTA-1 protein, coded by 95% of all chromosomes.

CONCLUSIONS

PCTA-1 is not a classical high risk gene with deleterious mutations predisposing to hereditary prostate cancer. Its contribution to prostate cancer susceptibility as a low risk factor in sporadic disease has to be assessed in larger samples by association studies.

Medical Imaging Informatics and Medical Informatics: opportunities and constraints. Findings from the IMIA yearbook of Medical Informatics 2002

OBJECTIVES

The Yearbook of Medical Informatics is published annually by the International Medical Informatics Association (IMIA) and contains a selection of recent excellent papers on medical informatics research (http://www.yearbook.uni-hd.de). The 2002 Yearbook of Medical Informatics took as its theme the topic of Medical Imaging Informatics. In this paper, we will summarize the contributions of medical informatics researchers to the development of medical imaging informatics, discuss challenges and opportunities of imaging informatics, and present the lessons learned from the IMIA Yearbook 2002.

RESULTS AND CONCLUSIONS

Medical informatics researchers have contributed to the development of medical imaging methods and systems since the inception of this field approximately 40 years ago. The Yearbook presents selected papers and reviews on this important topic. In addition, as usual, the Yearbook 2002 also contains a variety of papers and reviews on other subjects relevant to medical informatics, such as Bioinformatics, Computer-supported education, Health and clinical management, Health information systems, Knowledge processing and decision support, Patient records, and Signal processing.