Digital Medication Management in Polypharmacy—Findings of a Cluster-Randomized, Controlled Trial With a Stepped-Wedge Design in Primary Care Practices (AdAM)

BACKGROUND

Inappropriate drug prescriptions for patients with polypharmacy can have avoidable adverse consequences. We studied the effects of a clinical decision-support system (CDSS) for medication management on hospitalizations and mortality.

METHODS

This stepped-wedge, cluster-randomized, controlled trial involved an open cohort of adult patients with polypharmacy in primary care practices (=clusters) in Westphalia-Lippe, Germany. During the period of the intervention, their medication lists were checked annually using the CDSS. The CDSS warns against inappropriate prescriptions on the basis of patient-related health insurance data. The combined primary endpoint consisted of overall mortality and hospitalization for any reason. The secondary endpoints were mortality, hospitalizations, and high-risk prescription. We analyzed the quarterly health insurance data of the intention-to-treat population with a mixed logistic model taking account of clustering and repeated measurements. Sensitivity analyses addressed effects of the COVID-19 pandemic and other effects.

RESULTS

688 primary care practices were randomized, and data were obtained on 42 700 patients over 391 994 quarter years. No significant reduction was found in either the primary endpoint (odds ratio [OR] 1.00; 95% confidence interval [0.95; 1.04]; p = 0.8716) or the secondary endpoints (hospitalizations: OR 1.00 [0.95; 1.05]; mortality: OR 1.04 [0.92; 1.17]; high-risk prescription: OR 0.98 [0.92; 1.04]).

CONCLUSION

The planned analyses did not reveal any significant effect of the intervention. Pandemic-adjusted analyses yielded evidence that the mortality of adult patients with polypharmacy might potentially be lowered by the CDSS. Controlled trials with appropriate follow-up are needed to prove that a CDSS has significant effects on mortality in patients with polypharmacy.

How is leadership behavior associated with organization-related variables? Translation and psychometric evaluation of the implementation leadership scale in German primary healthcare

Background

The Implementation Leadership Scale (ILS) was developed to assess leadership behavior with regard to being proactive, knowledgeable, supportive, or perseverant in implementing evidence-based practices (EBPs). As part of a study on the implementation of a digitally supported polypharmacy management application in primary care, the original ILS was translated and validated for use in the German language.

Rationale

This study aimed to translate the original ILS into German and evaluate its psychometric properties.

Methods

The validation sample consisted of 198 primary care physicians in a cluster-randomized controlled trial in which the intervention group implemented a digitally supported clinical decision support system for polypharmacy management. The ILS was assessed using a 12-item scale. The study included a process evaluation with two evaluation waves between 2019 and 2021. The ILS was used within this process evaluation study to assess the leadership support with regard to the implementation of the polypharmacy management. The ILS was translated in a multi-step process, including pre-testing of the instrument and triple, back-and-forth translation of the instrument. We tested the reliability (Cronbach’s alpha) and validity (construct and criterion-related validity) of the scale.

Results

The four-dimensional structure of the instrument was confirmed (comparative fit index = .97; root mean square error of approximation = .06). Convergent validity was demonstrated by correlations with organizational innovation climate, social capital, and workload, which was consistent with the proposed hypothesis. Criterion-related validity of the ILS was demonstrated by predicting the organizational readiness for change scores using structural equation modeling. The reliability of the scale was good (α = .875).

Conclusion

The German version of the ILS created in this study is a reliable and valid measure. The original four-dimensional structure of the ILS was confirmed in a primary care setting. Further psychometric testing is needed to establish the validity and reliability of the ILS and to transfer it to other health care settings. It is a useful tool for identifying the areas for implementation leadership development. Further research is needed on how, why, and when distinct types of leadership behaviors have different effects on healthcare organizations in implementation processes.

Comparison of the Covered Self-Expandable Viatorr CX Stent with the Covered Balloon-Expandable BeGraft Peripheral Stent for Transjugular Intrahepatic Portosystemic Shunt (TIPS) Creation: a Single-Centre Retrospective Study in Patients with Variceal Bleeding

PURPOSE

This study compares the safety and efficacy of the ePTFE-covered self-expansible nitinol stent (VIATORR® Controlled Expansion, Gore, Flagstaff, USA) with the ePTFE-covered, balloon-expandable, metallic stent (BeGraft peripheral, Bentley, Hechingen, Germany) for the creation of the transjugular intrahepatic portosystemic shunt (TIPS).

MATERIAL AND METHODS

From September 2016 to December 2020, 72 consecutive patients receiving TIPS for acute variceal bleeding (rescue and early TIPS, n = 15) or for prophylaxis of variceal rebleeding (n = 57) were enrolled. The main contraindications were patients with vascular liver disease (portal vein thrombosis and Budd-Chiari syndrome). Forty patients (55.6%) received a Viatorr CX stent and 32 patients (44.4%) a BeGraft peripheral stent. Safety endpoints were technical and clinical adverse events and early deaths within 30 days after TIPS implantation. Efficacy endpoints were rebleeding rates, recurrence of large varices requiring endoscopic band ligation, or TIPS revision.

RESULTS

Groups receiving the Viatorr CX or BeGraft peripheral stent were comparable in all respects except the TIPS indication for acute variceal bleeding (5% vs. 25%, p = 0.015). All patients had a successful intervention, and the physical variables of stent implantation (intervention and fluoroscopy time, reduction of the portosystemic pressure gradient) as well as adjunctive embolization of varices were similar in both groups. Severe clinical complications (Viatorr CX: 5% vs. BeGraft peripheral: 3.1%, p = 0.692), post-TIPS hepatic encephalopathy (12.5% vs. 18.8%, p = 0.743) and death (5% vs. 0%, p = 0.793) were not different between Viatorr CX and BeGraft peripheral groups. With respect to efficacy, freedom from rebleeding and from variceal band ligation during follow-up (100% vs. 100%, p = 1.0), as well as the need for shunt revision (10.5% vs. 18.8%, p = 0.327), was comparable.

CONCLUSION

Compared to the present gold standard, the Viatorr CX stent, the balloon-expandable BeGraft peripheral stent, showed similar results with respect to safety and efficacy.

Effectiveness of the application of an electronic medication management support system in patients with polypharmacy in general practice: a study protocol of cluster-randomised controlled trial (AdAM)

INTRODUCTION

Clinically complex patients often require multiple medications. Polypharmacy is associated with inappropriate prescriptions, which may lead to negative outcomes. Few effective tools are available to help physicians optimise patient medication. This study assesses whether an electronic medication management support system (eMMa) reduces hospitalisation and mortality and improves prescription quality/safety in patients with polypharmacy.

METHODS AND ANALYSIS

Planned design: pragmatic, parallel cluster-randomised controlled trial; general practices as randomisation unit; patients as analysis unit. As practice recruitment was poor, we included additional data to our primary endpoint analysis for practices and quarters from October 2017 to March 2021. Since randomisation was performed in waves, final study design corresponds to a stepped-wedge design with open cohort and step-length of one quarter.

SCOPE

general practices, Westphalia-Lippe (Germany), caring for BARMER health fund-covered patients.

POPULATION

patients (≥18 years) with polypharmacy (≥5 prescriptions).

SAMPLE SIZE

initially, 32 patients from each of 539 practices were required for each study arm (17 200 patients/arm), but only 688 practices were randomised after 2 years of recruitment. Design change ensures that 80% power is nonetheless achieved.

INTERVENTION

complex intervention eMMa.

FOLLOW-UP

at least five quarters/cluster (practice). recruitment: practices recruited/randomised at different times; after follow-up, control group practices may access eMMa.

OUTCOMES

primary endpoint is all-cause mortality and hospitalisation; secondary endpoints are number of potentially inappropriate medications, cause-specific hospitalisation preceded by high-risk prescribing and medication underuse.

STATISTICAL ANALYSIS

primary and secondary outcomes are measured quarterly at patient level. A generalised linear mixed-effect model and repeated patient measurements are used to consider patient clusters within practices. Time and intervention group are considered fixed factors; variation between practices and patients is fitted as random effects. Intention-to-treat principle is used to analyse primary and key secondary endpoints.

ETHICS AND DISSEMINATION

Trial approved by Ethics Commission of North-Rhine Medical Association. Results will be disseminated through workshops, peer-reviewed publications, local and international conferences.

TRIAL REGISTRATION

NCT03430336. ClinicalTrials.gov (https://clinicaltrials.gov/ct2/show/NCT03430336).

Distinct Patterns of Blood Cytokines Beyond a Cytokine Storm Predict Mortality in COVID-19

Background

COVID-19 comprises several severity stages ranging from oligosymptomatic disease to multi-organ failure and fatal outcomes. The mechanisms why COVID-19 is a mild disease in some patients and progresses to a severe multi-organ and often fatal disease with respiratory failure are not known. Biomarkers that predict the course of disease are urgently needed. The aim of this study was to evaluate a large spectrum of established laboratory measurements.

Patients and Methods

Patients from the prospective PULMPOHOM and CORSAAR studies were recruited and comprised 35 patients with COVID-19, 23 with conventional pneumonia, and 28 control patients undergoing elective non-pulmonary surgery. Venous blood was used to measure the serum concentrations of 79 proteins by Luminex multiplex immunoassay technology. Distribution of biomarkers between groups and association with disease severity and outcomes were analyzed.

Results

The biomarker profiles between the three groups differed significantly with elevation of specific proteins specific for the respective conditions. Several biomarkers correlated significantly with disease severity and death. Uniform manifold approximation and projection (UMAP) analysis revealed a significant separation of the three disease groups and separated between survivors and deceased patients. Different models were developed to predict mortality based on the baseline measurements of several protein markers. A score combining IL-1ra, IL-8, IL-10, MCP-1, SCF and CA-9 was associated with significantly higher mortality (AUC 0.929).

Discussion

Several newly identified blood markers were significantly increased in patients with severe COVID-19 (AAT, EN-RAGE, myoglobin, SAP, TIMP-1, vWF, decorin) or in patients that died (IL-1ra, IL-8, IL-10, MCP-1, SCF, CA-9). The use of established assay technologies allows for rapid translation into clinical practice.

[Recommendations for Drug Treatment in Patients with Multimorbidity]

Applying guidelines in patients with multimorbidity can result in dangerous or contraindicated drug-drug and drug-disease-interactions. A representative working group of medical scientific associations identifies such therapeutic conflicts and develops management strategies that will be published as a formally consensus based (S2K) guideline. Rational, aims and methods used are described, as well as evaluation and updating of recommendations.

A prospective, multicentre study in acute non-cirrhotic, non-malignant portal vein thrombosis: comparison of medical and interventional treatment

BACKGROUND

To evaluate medical versus interventional treatment (transjugular thrombus fragmentation, local thrombolysis with or without stent implantation) in patients with acute non-cirrhotic, non-malignant portal vein thrombosis (PVT).

METHODS

This prospective, observational study enrolled 65 patients with acute (<28 days since begin of symptoms, no cavernoma) PVT in nine centres. Thirty patients received medical treatment and 35 patients received interventional treatment. PVT was graded into grade 1: short thrombosis and incomplete occlusion of the vessel lumen and grade 2: extended thrombosis or complete occlusion. Treatment response was classified as partial or complete, if thrombosis was reduced by one grade or to <25% of the vessel diameter respectively.

RESULTS

Partial and complete response rates were 7% and 30% in the medical compared to 17% and 54% (P < 0.001) in the interventional treatment group. In the multivariate analysis, interventional treatment showed a strong positive (OR 4.32, P < 0.016) and a myeloproliferative aetiology a negative (OR 0.09, P = 0.006) prediction of complete response. Complications were rare in the medical group and consisted of septicaemia and upper gastrointestinal bleeding of unknown origin in one patient each. Interventional treatment was accompanied by mild and self-limiting bleeding complications in nine patients, moderate intra-abdominal bleeding requiring transfusions (2 units) in one patient and peritoneal bleeding requiring surgical rescue in one patient. Four patients in each group developed intestinal gangrene requiring surgery. One patient died 52 days after unsuccessful interventional treatment.

CONCLUSIONS

Compared to medical treatment alone, interventional treatment doubled response rates at the cost of increased bleeding complications.

The federal standard medication plan in practice: An observational cross-sectional study on prevalence and quality

BACKGROUND

Medication plans are instruments used to document drug therapies, guide patients, and ensure medication safety. In Germany, patients who take at least 3 long-term medications are eligible to receive a medication plan. It has been statutory to use the federal standard layout (German: "Bundeseinheitlicher Medikationsplan") since April 2017.

OBJECTIVES

This study explores the prevalence, availability, medication discrepancies, and conformance with statutory regulations of medication plans since the introduction of the format of the federal standard medication plan in Germany.

METHODS

Medication reconciliation was performed for hospitalized patients according to the Best Possible Medication History principle. The collected medication lists were analyzed for medication discrepancies and conformance with the statutory regulations. The medication discrepancies were (1) omitted drugs, (2) additional drugs, and (3) dosing errors.

RESULTS

After hospitalization, 524 patients taking drugs were included. The majority (n = 424 patients) were eligible for a medication plan. While 241 medication lists were present, only 24.1% (n = 58) matched the federal standard format. The mean number of drugs was 6.3 ± 3.6, with 3315 medications (3046 long-term and 269 as needed) reconciled totally. The 84 medication lists with omitted or additional drugs included 166 medication discrepancies upon 774 drugs listed. Of the 253 patients with dosing errors, 146 had a medication list. Inappropriate dosages were due to single dose (n = 195), daily dose (n = 225) or frequency of application (n = 255).

CONCLUSION

Medication plans are valuable tools for patients and health care providers. This study shows that the introduced paper-based federal standard medication plan in Germany falls short of its expectations regarding availability and correctness. Switching to an electronic patient record system may overcome some of the current pitfalls.

Influence of hospitalization on prescribing safety across the continuum of care: an exploratory study

BACKGROUND

Transitions between different levels of healthcare, such as hospital admission and discharge, pose a considerable threat to the quality and continuity of drug therapy. This study aims to further explore the current role of hospitalization in prescribing error exposure and medication-related communication as patients are transferred from and back to ambulatory care.

METHODS

Assisted by electronic decision support, pre-admission and discharge medication regimens of 187 adult patients in a German university hospital were comparatively screened for clinically relevant categories of potentially inadequate prescribing. Binary logistic regression analyses were conducted to identify risk factors predisposing individuals to prescribing errors as a result of hospitalization. Additionally, it was established to what extent medication changes and potentially inappropriate prescribing decisions originating from inpatient treatment were communicated in discharge letters.

RESULTS

94.7% of the patients are subjected to differences between pre-admission and discharge prescriptions occurring at a rate of 461 per 100 hospitalizations. However, these modifications in drug therapy do not have a significant effect on the total number of potential prescribing errors per patient (p = 0.135) even though a large potential for improvement exists throughout the care continuum. For instance, almost a quarter of study participants with impaired kidney function lacks appropriate dose adjustment for one or more drugs before onset and at the end of inpatient treatment alike (22.5% [95% CI: 13.5%-34.0%] vs. 22.8% [95% CI: 14.1%-33.6%]). Overall, the probability of error exposure following hospitalization rises with an increasing number of prescribed drugs per patient, while individuals treated on surgical wards are four times more likely to be discharged with a prescribing-related safety hazard than their counterparts from medical departments (OR: 4.069 [95% CI: 1.126-14.703]; p = 0.032). In the study population's discharge summaries only 14.8% of medication changes and none of the potentially inappropriate prescribing decisions made during inpatient care are addressed, despite the latter occurring at a rate of 91 per 100 hospitalizations.

CONCLUSIONS

There is urgent need for standardized and evidence-based measures contributing to patient safety across sectorial interfaces of drug therapy. Our findings provide useful orientation for the targeted and rational design of such improvement strategies.

The use of health information technology in seven nations

OBJECTIVE

To assess the state of health information technology (HIT) adoption and use in seven industrialized nations.

DESIGN

We used a combination of literature review, as well as interviews with experts in individual nations, to determine use of key information technologies.

MAIN OUTCOME MEASURES

We examined rates of electronic health record (EHR) use in ambulatory care and hospital settings, along with current activities in health information exchange (HIE) in seven countries: the United States (U.S.), Canada, United Kingdom (UK), Germany, Netherlands, Australia, and New Zealand (NZ).

RESULTS

Four nations (the UK, Netherlands, Australia, and NZ) had nearly universal use of EHRs among general practitioners (each >90%) and Germany was far along (40-80%). The U.S. and Canada had a minority of ambulatory care physicians who used EHRs consistently (10-30%). While there are no high quality data for the hospital setting from any of the nations we examined, evidence suggests that only a small fraction of hospitals (<10%) in any single country had the key components of an EHR. HIE efforts were a high priority in all seven nations but the early efforts have had varying degrees of active clinical data exchange.

CONCLUSION

We examined HIT adoption in seven industrialized nations and found that many have achieved high levels of ambulatory EHR adoption but lagged with respect to inpatient EHR and HIE. These data suggest that increased efforts will be needed if interoperable EHRs are soon to become ubiquitous in these seven nations.

Impairment of health-related quality of life in functional dyspepsia and chronic liver disease: the influence of depression and anxiety

BACKGROUND

Health-related quality of life (HRQOL) is a marker of disease severity. Data on the relative impairment of HRQOL in chronic liver disease (CLD) and functional gastrointestinal disorders are lacking and no studies have assessed the link between impairment of HRQOL and psychosocial factors yet.

AIM

To assess predictors for, and the impairment of, HRQOL in CLD and FD.

METHODS

In 181 functional dyspepsia (FD) patients, 204 CLD patients and 337 healthy blood donors, HRQOL was assessed with the Short Form-36 (mental and physical component), and anxiety and depression utilizing the Hospital Anxiety and Depression Scale.

RESULTS

Compared with HC, HRQOL is significantly lower in FD and CLD (P-value for all <0.001). The mental but not physical component of HRQOL was significantly more impaired in FD compared with CLD (P < 0.05). After adjusting for confounders, impairment of mental (P < 0.001) and physical (P = 0.005) component of HRQOL was associated with the severity of CLD and FD. In FD, the multivariate analysis revealed depression and severity of symptoms as the most important predictors of HRQOL (R2 = 21.9 and 7.1). In CLD, the mental component of HRQOL was associated with depression and anxiety (R(2) = 9.9 and 9.7).

CONCLUSIONS

In tertiary care, HRQOL is more severely impaired in FD compared with CLD. Co-morbid psychiatric conditions significantly contribute to the impairment of HRQOL.

[Comorbidity of internal inpatients in the german diagnosis related groups-system]

The representation of comorbid mental disorders within the German Diagnosis Related Groups-System was investigated. First the complication and complexity level CCL of diagnoses of mental disorders (ICD-10 category F) within the G-DRG-calculation handbooks 2004 and 2005 were checked. Second the revenue based on a fictitious base rate of 3000 with the G-DRG versions 2004/2005 respectively was calculated with and without inclusion of diagnosed comorbid mental disorders of 6610 cases of both medical departments of a hospital of tertiary care level (year 2004). Only F0-diagnoses could lead to a CCL of 3. In 28.2 % of the patients at least one comorbid diagnosis of the category F of the International Classification of Diseases (mental and substance induced disorders) had been coded. Renunciation of the diagnosed mental disorders would have been resulted in a fictitious reduction in revenues based on the G-DRG version 2004 of 93 600 and on the G-DRG version 2005 of 69 000 . The Patient Clinical Complexity Level PCCL was increased 0.15 by the comorbid mental disorders in each year. To achieve an adequate representation of comorbid mental disorders in the G-DRG-system and to ensure a financial survival of psychosomatic/psychiatric CL-services coordinated efforts of psychosomatic scientific societies and hospitals taking part in the G-DRG-calculation sample are necessary.

[Frequency, relevance, causes of and strategies for prevention of medication errors]

Drug therapy has led to major advances in medicine. The beneficial effects of drug therapy are coupled with the inevitable risk of adverse drug reactions especially in elderly patients. Many adverse drug reactions are preventable. The electronic health card that will be introduced in Germany starting in 2006 is designed to support electronic decision support to prevent medication errors. Studies have demonstrated that CPOES can reduce medication errors by 80%. The necessary steps to improve medication safety in Germany are outlined and discussed.

[Is an evidence-based therapy of inpatients with type 2 diabetes possible from studies used for formulating therapy guidelines?]

BACKGROUND AND OBJECTIVE

Evidence-based guidelines are based on controlled trials and expert knowledge. Controlled trials often exclude elderly patients and those with diseases of several organs. It was the aim of this study to assess to what extent evidence-based guidelines of the German Diabetes Society (DDG) for antihyperglycaemic treatment were applicable to hospitalized patients with type 2 diabetes.

PATIENTS AND METHODS

The exclusion criteria of the clinical trials listed in the guidelines of the DDG (Diabetes und Stoffwechsel 12/2003; supplement 2, 29-31) were analysed. The study cohort consisted of all patients on drug treatment of type 2 diabetes who had been hospitalized during August and September 2003 in the two medical units of the Saarbrucken University Hospital. Current data on diabetes-associated and diabetes-dependent diseases were recorded.

RESULTS

91 of 125 literature citations (72%) contained clinical studies of evidence class I-III. 33.3% od studies had explicitly excluded patients with renal disease, 31.1% with liver disease, 10.9% with an age >75 years, 15.2% with coronary heart disease and 12.3% with heart failure. These exclusion criteria were used regardless of the drugs used. In 153 of 982 patients (15.5%) had drug-treated type 2 diabetes mellitus, median age was 73 years. In 138 of 153 patients (90.1%) medical and and social data could be obtained. 18.1% of these patients would have been excluded because their creatinine was >1.5 mg/dl, 45.5% because they were older then 75 years, 50.7% because they had coronary heart disease, and 15.9% because of heart failure (some patients met more than one of these items).

CONCLUSION

Treatment of hospitalized patients with type 2 diabetes with cardiac, hepatic and/or renal disease or older than 75 years was not possible if medical management was based on clinical studies with an evidence level I-III.

Biopsychosocial predictors of health-related quality of life in patients with chronic hepatitis C

OBJECTIVES

To assess biopsychosocial predictors of health-related quality of life (HRQOL) in patients with chronic hepatitis C.

METHODS

In 94 consecutive patients with chronic hepatitis C attending a liver center, HRQOL was assessed by the Medical Outcome Study Short Form Health Survey 36 (SF-36) and by the German version of the Chronic Liver Disease Questionnaire. The predictive effect on HRQOL of disease-related worries measured by the worry subscale of the Chronic Liver Disease Questionnaire, psychiatric comorbidity (defined by at least one Hospital Anxiety and Depression Scale German Version Score > or =11), the Child-Pugh score in case of cirrhosis, interferon therapy, and active medical comorbidities was assessed by a multiple regression analysis.

RESULTS

From 88 patients (age, 48.6 +/- 14.6 years; 50% female), 62 (70%) had no cirrhosis, 15 (17%) Child A, 5 (6%) Child B, and 6 patients (7%) Child C cirrhosis. The mental summary score of SF-36 was predicted by the amount of disease-related worries (corrected R2 = 0.33; beta = 3.2; p < .001) and psychiatric comorbidity (corrected R2 = 0.42; beta = -9.0; p < .001), by the physical summary score of SF-36 by the amount of disease related worries (corrected R2 = 0.33; beta = 4.0; p < .001), and by the number of active medical comorbidities (corrected R2 = 0.39; beta = -2.0; p = .006).

CONCLUSIONS

The HRQOL in chronic hepatitis C is not determined by the severity of the liver disease but by psychiatric and medical comorbidities and disease-related worries.

Validation of the German version of the Chronic Liver Disease Questionnaire

OBJECTIVE

The Chronic Liver Disease Questionnaire is an instrument for the assessment of health-related quality of life in patients with chronic liver diseases. So far it has not been validated for German speaking countries.

METHODS

Two hundred and three consecutive patients with chronic liver diseases (age, 52.7 +/- 13.9 years; 47% female; 45% no cirrhosis, 21% Child's class A, 15% Child's class B and 17% Child's class C cirrhosis; 52% with chronic viral hepatitis, 32% with alcoholic and 16% with other liver diseases) of a liver centre completed the German version of the Chronic Liver Disease Questionnaire (CLDQ-D), the Short Form Health Survey SF-36, the Hospital Anxiety and Depression Scale (HADS) and the Giessener Symptom List GBB-24. Fifty stable patients filled in the CLDQ-D a second time within 3 - 8 days.

RESULTS

With 97.7% completed items the acceptance by the patients was high. The internal consistency (Cronbach alpha) for the subscales ranged from 0.69 to 0.95, the test-retest reliability ranged from 0.79 to 0.88. The correlation coefficients with similar subscales of the instruments used for validation ranged between 0.5 and 0.9 (convergent validity). Patients with liver cirrhosis Child-Pugh stage C scored significantly lower in the subscales 'Abdominal Symptoms', 'Activity' and 'Worry', indicating a reduced health-related quality of life than in patients without cirrhosis (P < 0.05) (discriminant validity).

CONCLUSION

The CLDQ-D is well accepted by patients with chronic liver diseases and has good reliability and satisfactory discriminant validity.

[Chronic abdominal pain--internistic-psychosomatic aspects]

Abdominal pain is considered to be chronic when it persists for at least three months or when a patient experiences such pain for a total of three months during the course of a year. Pathophysiologically, nociceptive/neuropathic functional pain syndrome, mental disorders with the cardinal symptom of chronic pain, and mixed forms can be distinguished. In 50% of the patients, the cause of chronic abdominal pain is a functional gastrointestinal disorder e.g. functional dyspepsia irritable bowel syndrome. On the basis of a structured pain history, a physical examination and a basic "technical" diagnostic program (laboratory investigations, abdominal ultrasonography, Esophagogastroduodenoscopy, colonoscopy), correct assignment to one of the above-mentioned can be achieved in most of the cases.

The Budd-Chiari syndrome: outcome after treatment with the transjugular intrahepatic portosystemic shunt

BACKGROUND

The role of portosystemic shunting in the treatment of the Budd-Chiari syndrome is still under debate. Medical therapy and liver transplantation are alternative treatments. The aim of this study was to determine the outcome of a transjugular intrahepatic portosystemic shunt implantation.

METHODS

Thirty-five patients with severe Budd-Chiari syndrome and a Child-Pugh score of 9.2+/-1.9, who were not responsive to medical therapy, were elected for the transjugular shunt treatment, which was successfully accomplished in 33. Eleven patients had a fulminant/acute (history <2 months); 13, a subacute (<6 months); and 11, a chronic course of the disease. The shunt was established by using conventional self-expandable stents in 25 patients and polytetrafluoroethylene-covered stents in 8 patients. The mean follow-up was 37+/-29 months.

RESULTS

The shunt reduced the portosystemic pressure gradient from 29+/-7 to 10+/-4 mm Hg and improved the portal flow velocity from 9.2+/-11 to 51+/-17 cm/s. Clinical symptoms as well as the biochemical test results improved significantly during 4 weeks after shunt treatment. Three patients died and 2 received liver transplants. The cumulative 1- and 5-year survival rate without transplantation in all patients was 93% and 74%, respectively, and in patients with fulminant/acute disease 91% and 91% respectively (no deaths in this time period). On the average, 1.4+/-2.2 revisions per patient were needed during the mean follow-up of 3 years with a 1-year probability of 47%.

CONCLUSIONS

The transjugular shunt provides an excellent outcome in patients with severe fulminant/acute, subacute, and chronic Budd-Chiari syndrome. It may be regarded as a treatment for the acute and long-term management of these patients.

TIPS: an update

During the last 15 years the transjugular intrahepatic portosystemic shunt (TIPS) procedure has become a safe and effective treatment of portal hypertension. Its major obstacle, the high rate of shunt insufficiency, is going to be solved by the availability of covered stents showing a patency rate of up to 90%. The treatment of acute oesophageal and gastric variceal bleeding is an unsolved problem because variceal bleeding remains the major cause of death in patients with cirrhosis. TIPS has become the rescue treatment of choice because it combines high efficacy with low invasiveness. In this context, the timing of the rescue TIPS is of major importance for achieving definitive haemostasis before multi-organ failure develops. In the prevention of re-bleeding, TIPS is accepted as a second-line treatment, required in about 10-20% of patients. TIPS may be indicated when more than two significant re-bleedings occurred within a time frame of 12 months in spite of adequate first-line measures i.e. drugs or ligation. Refractory ascites is the third main indication for TIPS. Five randomized studies comparing TIPS with paracentesis show good response and comparable survival. Interpretations of authors and comments of reviewers are, however, controversial and do not permit a definitive recommendation.

Validation of the Inflammatory Bowel Disease Questionnaire IBDQ-D, German Version, for Patients with Ileal Pouch Anal Anastomosis for Ulcerative Colitis

BACKGROUND AND AIMS

The inflammatory bowel disease questionnaire (IBDQ) is the standard instrument for assessment of health-related quality of life (HRQOL) in patients with inflammatory bowel diseases. It has not been validated for patients with ileal pouch anal anastomosis (IPAA) and ulcerative colitis (UC).

METHODS

To determine acceptance (percentage of completed items), reliability (Cronbach's alpha of the IBDQ-D subscales) and convergent validity (correlations of the IBDQ subscales with the questionnaires used for validation) 61 patients with UC (age 52.7 +/- 13.9 years; 47 % female, 53 % male) and IPAA completed the German (Competence Network IBD) version of the Inflammatory Bowel Disease Questionnaire (IBDQ-D), the Short Form Health Survey (SF-36) the Hospital Anxiety and Depression Scale German Version (HADS-D) and the Giessener Symptom List (GBB 24). Face validity was assessed by a physicians' and patients' panel. All 37 patients underwent endoscopy making it possible to differentiate between patients with and without pouchitis (discriminant validity).

RESULTS

With 97.7 % completed items the acceptance was high. Cronbach's alpha value for the subscales ranged from 0.71 to 0.93. Missing items covering extraintestinal manifestations of IBD were criticized by patients. The correlation coefficients with comparable subscales of other instruments ranged between 0.41 and 0.76. Patients with clinical pouchitis scored significantly lower in all subscales than patients without pouchitis (p < 0.001).

CONCLUSION

The IBDQ-D has good acceptance, reliability, convergent and discriminant validity, but limited face and construct validity in patients with IPAA and UC.

Determinants of health-related quality of life in patients with chronic liver diseases

BACKGROUND AND AIMS

The study aims to assess influence of the liver disease, active medical and psychiatric comorbidities, and sociodemographic variables in the determination of health-related quality of life (HRQOL) measured by a generic and a liver-specific instrument in unselected patients with chronic liver disease.

METHODS

Two hundred four of 255 consecutive patients (80%) with all stages of various liver diseases attending a tertiary-care center completed the following self-report questionnaires: sociodemographic questionnaire of the Competence Network Bowel Disease, morbidity list of the German Pain Questionnaire, the German version of the Hospital Anxiety and Depression Scale (HADS-D), and Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) as generic instruments; and the German version of the Chronic Liver Disease Questionnaire (CLDQ) as a disease-specific HRQOL-instrument.

RESULTS

Stepwise multiple regression showed that cause of liver disease, severity of disease (cirrhosis vs. no cirrhosis, Child-Pugh score), sex, age, and social class had no effect on HRQOL. Anxiety resp. depression scores >/= 11 in the German version of the HADS, indicating a probable psychiatric disorder, contributed independently to the impaired HRQOL in the total score of the CLDQ and the Physical and Mental Summary Scores of the SF-36 (P < 0.0001). Number of active medical comorbidities contributed independently to the reduced HRQOL in the total score of the CLDQ and the Physical Summary Score of the SF-36 (P < 0.0001). Furthermore, the SF-36 Mental Summary Score was influenced negatively by active cardiovascular comorbidity (P < 0.003).

CONCLUSIONS

Psychiatric comorbidity and active medical comorbidity, and not severity of the liver disease according to Child-Pugh score, determine reduced HRQOL in patients with chronic liver diseases.

Validierung der deutschen Version der Fatigue Impact Scale FIS-D

OBJECTIVE

The Fatigue Impact Scale, FIS, is an internationally used instrument for the assessment of the impact of fatigue on Health-Related Quality of Life, HRQOL, also in patients with chronic liver diseases. In the German-speaking countries a validated instrument for measuring the impact of fatigue on patients with chronic liver diseases has not been available so far.

METHODS

The German linguistic adaptation of the FIS using a forward-backward procedure was administered to 204 patients (age 52,7 +/- 13,9 years; 47 % female, 53 % male, 45 % no cirrhosis, 22 % Child's A, 15 % Child's B and 17 % Child's C cirrhosis; 53 % with chronic viral hepatitis, 32 % with alcoholic and 15 % with other liver diseases) of a secondary care hospital. The following internationally accepted instruments were used for validation: The Short Form Health Survey, SF 36, the Hospital Anxiety and Depression Scale German Version, HADS-D, and the Giessener Symptom Scale, GBB 24. Fifty patients in clinically stable situation filled out the FIS-D within 3 - 8 days.

RESULTS

The acceptance of the FIS-D was high with 98 % answered items. The internal consistency of the three subscales was excellent (0.94 - 0.96), the test-retest reliability of the three subscales was good (0.72 - 0.83). The correlation coefficients with the validation instruments ranged between 0.49 and 0.80 (all p < 0 001). No differences in the FIS-D subscale scores were found in patients with and without cirrhosis and between the different Child-Pugh stages of liver cirrhosis. Patients treated with tranquilizer or antidepressants scored higher in the FIS-D than patients without this treatment (p < 0.05).

CONCLUSION

The FIS-D is well accepted by patients in clinical routine care and has been shown to have good acceptance and reliability in the assessment of fatigue in chronic liver patients.

Effect of the somatostatin analogue lanreotide on meal-stimulated portal blood flow in patients with liver cirrhosis

BACKGROUND

Lanreotide, a new long-acting somatostatin analogue, has been shown to inhibit the meal-stimulated increase of splanchnic blood flow in healthy volunteers. To date, similar data in patients with liver cirrhosis have not been available. We have examined the effect of lanreotide compared with placebo on meal-stimulated portal blood flow in patients with liver cirrhosis using Doppler ultrasound.

METHODS

20 cirrhotic patients (placebo n = 12, lanreotide n = 8) with proven portal hypertension were studied after an overnight fast. Lanreotide, at a dose of 100 microg/h, was infused intravenously over 7 h after a 1-hour basal period. In parallel to the intravenous infusion, a liquid test meal (Ensure plus, 1.5 kcal/min) was perfused for 7 h through an intraduodenal tube at a rate of 3 ml/min. Blood pressure, heart rate and portal vein blood flow (PVF, ml/min, Doppler technique) were determined at regular intervals.

RESULTS

Baseline PVF amounted to 725 +/- 182 ml/min in the placebo and to 917 +/- 252 ml/min in the lanreotide group (n.s.). The meal-stimulated increase in PVF was blunted by lanreotide (AUC, % x min): 62,709.6 +/- 6,817 (placebo) vs. 45,237 +/- 2,507 (lanreotide), p < 0.05. Lanreotide also blunted the postprandial increase in heart rate for the first 2 h of meal perfusion.

CONCLUSIONS

Because of potent inhibition of postprandial splanchnic hyperemia in patients with liver cirrhosis, lanreotide may be useful in the treatment of complications of portal hypertension.

[Psychophysiology of visceral pain syndromes]

Psychosomatics of visceral pain syndromes. From a psychosomatic point of view visceral pain syndromes can be classified into nociceptive (somatic and visceral) pain syndromes without and with maladaptive pain coping resp.psychic comorbidity, functional pain syndromes (typical symptom clusters without biochemical or structural abnormalities in clinical routine diagnostics) and psychic disorders with pain as main symptom. With regard to the etiology and the course of chronic inflammatory bowel diseases (IBD) as representatives of somatic pain syndromes and of irritable bowel syndrome/chronic pelvic pain as representatives of functional pain syndromes empirically validated psychosocial aspects are summarized: Personality traits, illness behavior, daily hassles, life events and psychic comorbidity and effects of psychotherapy. Psychosocial factors are decisive in the etiology and the course of functional pain syndromes as determinants of their severity (psychosomatic disease in a narrow sense). Psychosocial factors are not decisive for the etiology, but for the course of IBD (psychosomatic disease in a broader sense). Within general pain therapy of visceral pain syndromes a biopsychosocial approach should be applied right from the beginning (psychosomatic basic care). Within special pain therapy of visceral pain syndromes a qualified psychiatric - psychotherapeutic diagnostics and co-therapy should be mandatory.

[Tobacco associated gastrointestinal disorders: smoking cessation therapy - a task for gastroenterologists]

Tobacco smoking is an independent risk factor in the etiology of Crohn's disease, functional dyspepsia, GERD, chronic pancreatitis and gastrointestinal carcinomas (oesophagus, stomach, colon, pancreas and liver). The current knowledge of the effects of tobacco smoking on the gastrointestinal tract is summarised. Non-smoking should be recommended to everybody as primary prevention against cardiopulmonary and gastrointestinal diseases. Despite lacking of clinical studies tobacco abstinence should be recommended as a secondary preventive therapy of Crohn's disease, functional dyspepsia, GERD and chronic pancreatitis because of epidemiological studies and pathophysiological considerations. All gastroenterologists should help patients with the above mentioned diseases to stop smoking. Evidence based methods of smoking cessation and methods suited to routine clinical care are presented. Pharmacological (nicotine replacement therapy) and psychological therapies (cognitive behavioural group therapies) should be adapted to the prior experiences of the patient, his stage of motivation to stop smoking and his co-morbidity. In refractory ulcerative colitis controlled tobacco smoking can be recommended to ex-smokers.

[Colitis ulcerosa and opioid addiction]

The occurrence of an opioid addiction within an opioid treatment of pain or diarrhoea in inflammatory bowel disease is rarely reported. We report on a 36-year-old male with a 14 years lasting left sided chronic ulcerative colitis who developed after the initiation of a therapy with tincture of opium because of abdominal pain and diarrhoea an opioid addiction with the consumption of opium and later buprenorphin. Additionally to the diagnostics and therapy of the ulcerative colitis a detoxication was carried out. The diarrhoea slightly increased during the buprenorphin withdrawal. Diarrhoea refractory to other treatment should be treated by loperamid because of its lacking effects on the central nervous system. In chronic abdominal or musculoskeletal pain in inflammatory bowel disease opioids can be used if no surgical or other medical pain relief is possible. A consequent control of the therapeutic and side effects of the opioid therapy is necessary, especially of an abuse of opioid medication. The published case reports of a therapeutic induction of opioid addiction demonstrate that psychiatric comorbidity is an essential or even necessary risk factor. A checklist with seven criteria of opioid addiction during opioid therapy is presented.

[Smoking cessation. A physician's responsibility]

Giving up smoking is a cost-effective measure in the secondary prevention of chronic arterial disease and chronic obstructive pulmonary disease. The involvement of the physician in the primary prevention of smoking and kicking the habit in the case of tobacco-related disease, must receive greater emphasis than has so far been the case in Germany. Weaning smokers suffering from tobacco-related disease from their habit is a task for the physician, and may take the form either of a single minimal intervention, or successive consultations that can be integrated in every medical activity. The concept of stepwise smoking dishabituation is supported by evidence-based consensus recommendations on the part of relevant national and international medical societies and public institutions.

[Chronic intestinal pseudo-obstruction. Clinical symptomatology and course]

BACKGROUND AND OBJECTIVE

Chronic intestinal pseudoobstruction (CIP) is a motility disorder clinically characterized by recurrent symptoms of small intestinal or large bowel obstruction without organic stenosis. The aim of the present study was to assess the clinical presentation and course of the disease.

PATIENTS AND METHODS

During a four year period all available data including the symptoms as assessed by the bowel disease questionnaire (BDQ) of all patients with newly established diagnosis of CIP were analyzed including duration of symptoms and previous surgical interventions due to the abdominal symptoms.

RESULTS

Data of nine patients (five females, four males, age 20 - 64 years) with newly diagnosed CIP were available for analysis. Median age at initial onset of symptoms were 24 years. The final diagnosis of CIP was established after a median of 7 years (range 1 - 20). Initially, the majority of patients suffered from uncharacteristic symptoms such as abdominal fullness and abdominal pain. All patients had undergone repeated abdominal surgical interventions for suspected mechanical bowel obstruction. On average, the first surgical intervention was performed 5 years after the onset of symptoms and there was a median number of 10 treatments as in-patients. Suspected acute bowel obstruction occurred between 1 and 14 times and laparotomies were performed in 50 % of these events.

CONCLUSION

The diagnosis of CIP is usually preceded by several years with uncharacteristic abdominal symptoms. During this time, most patients undergo multiple surgical interventions. Thus, in patients with repeated suspected acute bowel obstruction without definite proof of mechanical obstruction, CIP has to be taken into consideration as differential diagnosis. In this context, small bowel manometry is an important diagnostic tool.

[Measuring quality of life in gastroenterology--concepts, instruments and problems]

Health-related quality of life (HRQOL) is becoming an increasingly more important primary or secondary end point of clinical studies. Patients and their self help organizations demand a greater regard to their subjective experience of their disease and its treatment. Cost-effectiveness analyses measuring quality-adjusted life years are becoming more and more decisive in health politics. Therefore it is important for gastroenterologists to know the concepts and methods of HRQOL-measurement. The present article discusses the definitions of (health-related) quality of life and reviews generic- and disease-specific quality of life instruments in gastroenterology including quality criteria. Rules for the adaptation of Anglo-American questionnaires into German-speaking countries are pointed out. Finally the limitations of the concepts of HRQUOL and its measurement are discussed.

Antisecretory mechanisms of peptide YY in rat distal colon

Peptide YY (PYY) is a potent regulator of intestinal secretion. These studies investigated the role of Y1 and Y2 receptor subtypes in mediating the antisecretory effects of PYY on mucosa-submucosa preparations of rat distal colon. Addition of vasoactive intestinal peptide (VIP) to these tissues resulted in a 140 +/- 18% increase in basal short-circuit current (Isc) and the induction of Cl- secretion. VIP-stimulated increases in Isc were abolished by the addition of each of PYY, (Pro34)-PYY, a Y1 receptor-selective agonist, and PYY-(3-36), an endogenous Y2 receptor-selective ligand. However, when tissue neural transmission was blocked with tetrodotoxin, neither PYY nor its receptor subtype-selective analogs were able to inhibit VIP-stimulated increases in Isc. These results suggest that in the rat distal colon, the antisecretory actions of PYY are mediated through a combination of Y1 and Y2 receptor subtypes or through a novel receptor subtype that is unable to discriminate between (Pro34)-PYY and PYY-(3-36).

Altered postprandial motility in chronic pancreatitis: role of malabsorption

BACKGROUND & AIMS

Intraileal nutrients modulate gastrointestinal motility, but effects of maldigestion on postprandial motility are unknown. The aim of this study was to compare motor responses with ileal nutrient exposure in health and pancreatic insufficiency after a meal or intraluminal perfusion.

METHODS

After oroileal multilumen intubation for duodeno-jejuno-ileal sampling, marker perfusion, and motility recording, 14 normal subjects and 12 patients with severe pancreatic insufficiency received a labeled liquid meal twice, either with placebo or pancreatin. Effects of intraileal nutrient perfusion on fed motility induced by duodenal amino acid perfusion were also investigated.

RESULTS

Compared with normals, untreated patients had greater cumulative ileal nutrient delivery (69 +/- 21 vs. 487 +/- 232 kJ), shorter fed pattern (196 +/- 22 vs. 131 +/- 14 minutes), greater 90% gastric emptying (163 +/- 12 vs. 128 +/- 10 minutes), and faster small intestinal transit (86 +/- 9 vs. 44 +/- 6 minutes). Pancreatin reversed these changes. Ileal nutrient perfusion converted fed into interdigestive-like motility in normals (7 of 8) and patients (4 of 5).

CONCLUSIONS

In subjects with pancreatic insufficiency, a low-energy liquid meal induces shorter fed motor pattern associated with accelerated gastric emptying and intestinal transit compared with healthy subjects. Because changes responded to enzyme treatment and could be reproduced by ileal nutrient perfusion, ileal delivery of malabsorbed chyme may be involved as a mechanism.

Neuropeptide Y 3-36 is an endogenous ligand selective for Y2 receptors

Neuropeptide Y (NPY 1-36) binds to Y1 and Y2 receptors with similar affinity. No endogenous molecular form of NPY with selectivity for Y1 or Y2 receptors has been described so far. We report the presence of an endogenous fragment of NPY in porcine brain, NPY 3-36, which lacks the amino-terminal dipeptide Tyr-Pro of NPY 1-36. NPY 3-36 accounts for 35% of NPY-like immunoreactivity in porcine brain. We have compared binding of NPY 3-36 and NPY 1-36 in model systems of Y1-like (SK-N-MC cells) and Y2-like receptors (CHP234 cells). NPY 3-36 and NPY 1-36 had similarly high affinity for Y2-like receptors on CHP234 cells, but NPY 3-36 had a 1000-fold lower affinity than NPY 1-36 for Y1-like receptors on SK-N-MC cells. Thus amino-terminal cleavage of NPY 1-36 generating NPY 3-36 converts an unselective Y1/Y2 receptor ligand into a highly Y2 selective ligand. This may be a means of fine tuning NPY biological actions.

Inhibition of canine exocrine pancreatic secretion by peptide YY is mediated by PYY-preferring Y2 receptors

It is still unclear, which receptor subtype, Y1 and/or Y2, mediates the inhibitory action of PYY on exocrine pancreatic secretion. The present study was undertaken to characterize functionally the Y receptor subtype that mediates the inhibition of exocrine pancreatic secretion by peptide YY (PYY). In eight conscious dogs with chronic gastric and pancreatic fistulas, we compared the action of intravenous infusion of 200 and 400 pmol/kg/h of the Y receptor agonists PYY 1-36, PYY 3-36, PYY 13-36, Pro34PYY 1-36, and NPY 1-36 on the pancreatic secretory response to secretin (20.5 pmol/kg/h) and cerulein (29.6 pmol/kg/h). PYY 13-36, Pro34PYY 1-36, and NPY 1-36 were also studied by giving a fivefold dose (1,000 and 2,000 pmol/kg/h). PYY 1-36 and the Y2 receptor agonist PYY 3-36 significantly inhibited pancreatic secretory responses to secretin and cerulein, whereas inhibition by NPY 1-36 and the Y2 receptor agonist PYY 13-36 was attainable only at doses of 1,000 and 2,000 pmol/kg/h. The Y1 receptor agonist Pro34PYY 1-36 was without effect on pancreatic secretion. We conclude that in dogs the inhibition of exocrine pancreatic secretion by PYY is mediated via Y2 receptors of a PYY-preferring subtype.

Reversal by NPY, PYY and 3-36 molecular forms of NPY and PYY of intracisternal CRF-induced inhibition of gastric acid secretion in rats

1. The Y receptor subtype involved in the antagonism by neuropeptide Y (NPY) of intracisternal corticotropin-releasing factor (CRF)-induced inhibition of gastric acid secretion was studied in urethane-anaesthetized rats by use of peptides with various selectivity for Y1, Y2 and Y3 subtypes: NPY, a Y1, Y2 and Y3 agonist, peptide YY (PYY), a Y1 and Y2 agonist, [Leu31, Pro34]-NPY, a Y1 and Y3 agonist, NPY(3-36) and PYY(3-36), highly selective Y2 agonists and NPY(13-36) a weak Y2 and Y3 agonist. Peptides were injected intracisternally 10 min before intracisternal injection of CRF (10 micrograms) and gastric acid secretion was measured by the flushed technique for 1 h before and 2 h after pentagastrin-(10 micrograms kg-1 h-1, i.v.) infusion which started 10 min after CRF injection. 2. Intracisternal injection of CRF (10 micrograms) inhibited by 56% gastric acid secretion stimulated by pentagastrin. Intracisternal injection of NPY and PYY (0.1-0.5 microgram) did not influence the acid response to pentagastrin but blocked CRF-induced inhibition of pentagastrin-stimulated acid secretion. NPY(3-36) (0.5 microgram) and PYY(3-36) (0.25 and 0.5 microgram) also completely blocked the inhibitory action of CRF on pentagastrin-stimulated acid secretion. 3. [Leu31, Pro34]-NPY (0.5-5 micrograms) and NPY(13-36) (0.5-5 micrograms) injected intracisternally did not modify gastric acid secretion induced by pentagastrin or CRF inhibitory action. 4. The sigma antagonist, BMY 14802 (1 mg kg-1, s.c.) did not influence the acid response to pentagastrin but prevented the antagonism by PYY(3-36) (0.5 microgram) of the CRF antisecretory effect. 5. These results show that both PYY and NPY and the 3-36 forms of PYY and NPY are equipotent in blocking central CRF-induced inhibition of pentagastrin-stimulated gastric acid secretion. The structure-activity profile suggests a mediation through Y2 receptor subtype and the involvement of sigma binding sites.

Inhibitory effect of PYY on vagally stimulated acid secretion is mediated predominantly by Y1 receptors

Two molecular forms of peptide YY (PYY), PYY-(1--36) and PYY-(3--36), are abundant in rabbit intestine and blood. We have previously shown that PYY-(1--36) (PYYI) activates equipotently Y1 and Y2 receptors and PYY-(3--36) (PYY II) is a highly selective agonist for Y2 receptors. In the present study, we examined the effect of exogenous infusion of PYY on vagally stimulated gastric acid secretion in awake rabbits with chronic gastric fistula. To determine the specific PYY receptor(s) that mediates this effect, we used a highly selective Y1 agonist, Pro34-PYY, a synthetic PYY, and a Y2-selective agonist, PYY II. Vagal stimulation of acid secretion was elicited by an intravenous bolus injection of insulin (0.125 U/kg) 30 min after beginning a 180-min intravenous infusion of either PYY I, PYY II, or [Pro34]-PYY after a 50 micrograms/kg i.v. bolus of atropine followed immediately by a 500 micrograms/kg sc injection. During infusion of 200 pmol.kg 1.h-1 PYY I, acid output was significantly inhibited to 45 +/- 13% of maximum acid output 60 min after injection of insulin. Similarly, acid output during infusion of 200 pmol.kg-1.h-1 [Pro34]-PYY was significantly inhibited to 52 +/- 12% of maximum. In contrast, acid output during infusion of 200 pmol.kg-1.h-1 of PYY II was not significantly inhibited (101 +/- 18% of maximum). Infusion of double the dose (400 pmol.kg-1.h-1) of PYY II resulted in acid inhibition (51 = 15% of maximum), whereas infusion of the same dose did not significantly enhance acid inhibition by infusion of either PYY I or [Pro34]-PYY (28 +/- 11 and 42 +/- 15% of maximum). These results indicate that PYY, acting predominantly at Y1 receptors, is a potent inhibitor of vagally stimulated acid secretion in adult rabbits.

Ileal release of glucagon-like peptide-1 (GLP-1). Association with inhibition of gastric acid secretion in humans

There is evidence that the distal intestine participates in the regulation of gastric motor and secretory function. It was the aim of this study to examine in greater detail the effects of ileal nutrient exposure on human gastric acid secretion and to investigate potential intermediary mechanisms. Twelve normal subjects were intubated with an oroileal multilumen tube assembly for gastric, duodenal, and ileal perfusion of marker and test solutions, aspiration, and intestinal manometry. We studied ileal effects on gastric acid output in the unstimulated, interdigestive state (during early phase II, N = 6), and during endogenous stimulation by intraduodenal essential amino acid perfusion, N = 6) and on release of candidate humoral mediators, peptide YY (PYY) and glucagonlike peptide-1 (GLP-1), both known inhibitors of human gastric acid secretion. Compared with ileal saline perfusion, ileal carbohydrate (total caloric load: 60 kcal) decreased interdigestive gastric acid output by 64% (P < 0.01), and endogenously stimulated output by 68%, respectively (P < 0.005). Under all experimental conditions, ileal carbohydrate increased plasma GLP-1 by 80-100% (all P < 0.005). Ileal lipid perfusion had similar inhibitory effects on gastric acid output and stimulatory effects on GLP-1 release as had ileal carbohydrate. By contrast, ileal perfusion with peptone had no or only weak effects on either acid output or plasma GLP-1. Plasma PYY concentrations and suppression of gastric secretion in response to ileal perfusions were not correlated. In humans, both interdigestive and endogenously stimulated gastric acid output are inhibited in response to intraileal carbohydrate or lipids, but not protein.(ABSTRACT TRUNCATED AT 250 WORDS)

Peptide YY inhibits exocrine pancreatic secretion in isolated perfused rat pancreas by Y1 receptors

Peptide YY (PYY) inhibits exocrine pancreatic secretion in several species. Two receptors, Y1 and Y2, are known to mediate PYY actions. While PYY 1-36 binds equally to both receptor subtypes, a second endogenous form of PYY, PYY 3-36, selectively activates Y2 receptors. The importance of Y receptor subtypes for inhibition of exocrine pancreatic secretion by PYY is unknown. We studied the effects of PYY 1-36 on cholecystokinin octapeptide (CCK-8)-stimulated amylase secretion in an isolated perfused rat pancreas model. To characterize functionally the receptors involved we determined the effects of a Y1-selective agonist, [Pro34]PYY; a Y2 selective agonist, PYY 3-36; and neuropeptide Y (NPY) in this model. PYY 1-36 significantly inhibited stimulated amylase secretion in the denervated rat pancreas. [Pro34]PYY and NPY both inhibited exocrine pancreatic secretion as potently as PYY 1-36. Contrary to that, the Y2 selective agonist, PYY 3-36, was inactive. We conclude that PYY inhibits exocrine pancreatic secretion in this extrinsically denervated rat pancreas model by Y1 receptors.

[Pro34]peptide YY is a Y1-selective agonist at peptide YY/neuropeptide Y receptors

We have investigated binding and functional effects of a new peptide YY analogue, [Pro34]peptide YY, at Y1 and Y2-like subtypes of receptors for peptide YY and neuropeptide Y. In binding studies [Pro34]peptide YY had a similarly high affinity as peptide YY to human Y1-like receptors in SK-N-MC cells, a human neuroblastoma cell line of presumed neurogenic origin, and HEL cells, a human cell line derived from a patient with Hodgkin's disease. In functional studies [Pro34]peptide YY stimulated Ca2+ elevations in both Y1-like receptor cell lines with similar potency and efficacy as peptide YY. In contrast to peptide YY [Pro34]peptide YY was 1000-fold less potent in binding to Y2-like receptors in porcine splenic membranes and lacked agonistic effects in another Y2-like receptor-mediated model system, i.e. inhibition of [3H]serotonin release from rat cerebral cortical slices. Thus, [Pro34]peptide YY is a highly Y1-selective full agonist of peptide YY/neuropeptide Y receptors. [Pro34]peptide YY could be useful for studying the importance of Y receptor subtypes in mediating peptide YY physiological actions.

Two molecular forms of peptide YY (PYY) are abundant in human blood: characterization of a radioimmunoassay recognizing PYY 1-36 and PYY 3-36

Two endogenous forms of PYY are abundant in man and dog, PYY 1-36 (PYY-I) and PYY 3-36 (PYY-II). PYY-II is a major molecular form of PYY in human colon, but it is not known, whether PYY-II is also released into the circulating blood. Several radioimmunoassays for measuring PYY-I in plasma have been developed, but it has not been reported, whether they equally detect PYY-II. We characterize a radioimmunoassay for measuring PYY in human plasma which equally recognizes PYY-I and PYY-II. Using this radioimmunoassay and reversed phase HPLC we demonstrate the existence of two forms of PYY in human blood, coeluting with synthetic PYY-I and PYY-II.